Objective To construct reference ranges of cardiac size and morphologic parameters in low-risk fetuses at 28-39 gestational weeks using two-dimensional speckle tracking technique.Methods A prospective collection of 453 low-risk singleton pregnancies with echocardiography at Obstetrics and Gynecology Hospital,Fudan University was used to assess the size(length,width,and area)and morphology(sphericity index,i.e.,the ratio of length to width)of the fetal four-chamber view and two ventricles using two-dimensional speckle tracking technique.Repeated inter-and intra-observer agreement of measurements was assessed using the intraclass correlation coefficients(ICCs).Statistical analysis of cardiac measurement parameters was performed to establish reference ranges of values for cardiac size and morphology in low-risk fetuses.Results The inter-and intra-group ICCs for reproducibility tests of fetal cardiac parameters measurements were 0.691 to 0.980.Fetal four-chamber view and ventricular size increased with gestational week(all P<0.001),the end-diastolic length of the left ventricle was larger than that of the right ventricle,and the end-diastolic diameter was smaller than that of the right ventricle(both P<0.001),while there was no significant difference in the end-diastolic area of the two ventricles(P= 0.050).The spherical index of four-chamber view did not correlate with gestational week(P=0.811).The sphericity index of the basal and intermediate segments of the left ventricle was greater than that of the right ventricle,and the sphericity index of the apical segment was less than that of the right ventricle,the differences were statistically significant(all P<0.01).Conclusion The two-dimensional speckle tracking technique for measuring fetal cardiac parameters has good reproducibility.The reference ranges for cardiac size and morphology in low-risk fetuses developed in this study will be useful for prenatal evaluation of cardiac remodeling.

Objective: To establish an optimized method for isolation and purification of microglia from aged rat brain tissue, and the phenotype of microglia was detected by flow cytometry. Methods: With young rats(3 months old) as control, the brain tissues of aged rats were immediately processed into single cell suspensions by mechanical dissociation and enzymatic digestion using type IV collagenase. Microglia were isolated on Percoll gradients(30%-37%-70%). The cells were stained with fluorescence-labeled antibodies and the phenotype of microglia was detected by flow cytometry. Results: This study developed a method that enzymatic digestion and mechanical dissociation combined with density gradient centrifugation. More single cells could be obtained by using this method. And the survival rate of cells was more than 90%. The flow cytometric analysis showed that the expression of M1 microglia marker CD86 and MHC Ⅱ increased(P<0.01), and the expression of M2 microglia marker CD200R increased(P<0.01) in aged rats compared with that in young rats. Conclusion The use of type IV collagenase and mechanical digestion combined with density gradient centrifugation is good for isolating and purifying microglia from adult and aged rat brain tissue.

ObjectiveBody fluid stains left at crime scenes are frequently trace amounts, while the identification of body fluids through real time fluorogenic quantitative technique often necessitates the repeated detection within the limited sample, as multiple miRNA markers are the basis for the identification. Based on the goal of both the throughput and efficiency improvement of miRNA analysis in trace samples, a duplex real time fluorogenic quantitative PCR assay system was designed to accurately quantify two miRNAs simultaneously, and the system should be further verified by actual sample for the body fluid identification. MethodsThe duplex real time fluorogenic quantitative PCR system of miR-451a to miR-21-5p was established with specially designed primers and probes, and the concentrations of the primers and probes were both optimized. The specificity, sensitivity and reproducibility of the system were validated, while its capability for body fluid identification was assessed using the miR-451a to miR-21-5p ratio. ResultsThe optimized assay system exhibited excellent specificity and repeatability, with coefficients of variation consistently below 8% for both intra- and inter-batch variability. The amplification efficiency of miR-451a and miR-21-5p reached 71.77% and 74.81%, respectively, with high and relatively consistent results. By utilizing this duplex real time fluorogenic quantitative PCR assay system, a total of 58 body fluid samples were analyzed, exhibiting a discrimination rate of 100% between blood and non-blood samples, as well as between peripheral blood and menstrual blood samples. Moreover, the results, obtained from single real time fluorogenic quantitative PCR assay system and duplex real time fluorogenic quantitative PCR assay system, showed no statistically significant difference with randomly selected blood samples (n=20). Compared to previous single real time fluorogenic quantitative PCR assay system, the sensitivity of duplex real time fluorogenic quantitative PCR assay system exhibited remarkable improvement. A minimum input of only 0.1 ng total RNA was sufficient for accurate detection of peripheral blood and menstrual blood samples, while saliva, semen, and vaginal secretion required only 1 ng total RNA for precise identification purposes. Additionally, the duplex real time fluorogenic quantitative PCR assay system successfully differentiated between different types of body fluids in simulated samples under natural outdoor conditions. ConclusionThe duplex real time fluorogenic quantitative PCR assay system effectively reduced both the time and material costs by half compared to the single system, especially suitable for the examination of body fluid stains left at crime scenes, solving the contradiction between the trace amount and the multiple sample volumes demand of repeated real time fluorogenic quantitative PCR. The duplex real time fluorogenic quantitative PCR assay successfully distinguished blood and other body fluid, as well as peripheral blood and menstrual blood samples, which maintains an equivalent capability for body fluid identification with half sample, time and reagent consumption. This system provides an efficient tool for identifying suspicious body fluids, as well as a foundation for more multiplexed real time fluorogenic quantitative PCR assay system research.

Circulating tumor DNA (ctDNA) comes from tumor, reflecting the genetic information of the tumor well, and will change with the progress of tumor. In recent years, the unique capabilities of ctDNA have attracted much attention and been widely studied. In this paper, based on the summary of the source, properties and sample processing of ctDNA, its detection technology and application in cancer diagnosis and treatment are reviewed. The roles and importance of ctDNA reference material in second-generation sequencing are described. The urgency of establishing uniform standards and specifications of ctDNA in various processes, such as samples collection, storage, quantitative testing and data analysis, has been pointed out.

Objective This study aims at establishing a teaching catalog and content for breast rare dis-eases and developing the syllabus for the breast rare disease using integrated multimodality of case-/problem-/resource-based learning(CBL+PBL+RBL).Methods By conducting bibliometrics co-occurrence analysis,we collected 6291 articles on breast rare disease published from January,1975 to June,2024.Additionally,we re-trieved the Textbook on Rare Diseases,the Catalog of Chinese Rare Disease,and Second Batch of Rare Dis-ease Catalog and then decided the teaching content.Results From 16,387 keywords,1000(6.1％)keywords were identified through co-occurrence analysis,including 50(0.3％)candidate diseases.These were classified into three categories:rare primary breast diseases,rare genetic mutation-related diseases associated with breast cancer,and rare systemic multi-system diseases involving the breast.From the candidate list,20(0.1％)rare primary breast diseases were further selected for their notable clinical teaching significance,and significant multi-systemic diseases affecting the breast,whether related to gene mutations or not.Teaching plans were draf-ted using a diversified parallel teaching approaches,taking into account the characteristics of different diseases and the focus of different teaching methods.Conclusions This study initiated the development of the teaching content for breast rare diseases and developed the teaching syllabus using the CBL+PBL+RBL integrated multi teaching model and targeting each rare breast disease for the critical point for teaching.

Objective To understand the respiratory protection competency of staff in hospitals.Methods Staff from six hospitals of different levels and characteristics in Beijing were selected,including doctors,nurses,medical technicians,and servicers,to conduct knowledge assessment on respiratory protection competency.According to exposure risks of respiratory infectious diseases,based on actual cases and daily work scenarios,content of respira-tory protection competency assessment was designed from three aspects:identification of respiratory infectious di-seases,transmission routes and corresponding protection requirements,as well as correct selection and use of masks.The assessment included 6,6,and 8 knowledge points respectively,with 20 knowledge points in total,all of which were choice questions.For multiple-choice questions,full marks,partial marks,and no mark were given respective-ly if all options were correct,partial options were correct and without incorrect options,and partial options were correct but with incorrect options.Difficulty and discrimination analyses on question of each knowledge point was conducted based on classical test theory.Results The respiratory protection competency knowledge assessment for 326 staff members at different risk levels in 6 hospitals showed that concerning the 20 knowledge points,more than 60％participants got full marks for 6 points,while the proportion of full marks for other questions was relatively low.Less than 10％participants got full marks for the following 5 knowledge points:types of airborne diseases,types of droplet-borne diseases,conventional measures for the prevention and control of healthcare-associated infec-tion with respiratory infectious diseases,indications for wearing respirators,and indications for wearing medical protective masks.Among the 20 knowledge questions,5,1,and 14 questions were relatively easy,medium,and difficult,respectively;6,1,4,and 9 questions were with discrimination levels of ≥0.4,0.30-0.39,0.20-0.29,and ≤0.19,respectively.Conclusion There is still much room for hospital staff to improve their respiratory protection competency,especially in the recognition of diseases with different transmission routes and the indications for wearing different types of masks.

Objective Personalized calculation of contrast agent dose based on body surface area(BSA)was conducted to explore the feasibility of obtaining virtual single energy or reconstruction fusion through dual-energy CT without affecting the enhancement effect of portal vein trunk under the condition of reducing the contrast agent dose.Methods A total of 60 patients who received enhanced upper abdominal CT examination in the First Affiliated Hospital of Army Medical University were selected and divided into the normal dose group and the reduced dose group.The normal dose group used the BSA estimated value as the contrast agent dose,and the reduced dose group used the BSA estimated value reduced by 20%as the contrast agent dose.Both groups of patients were treated with dual-energy CT scanning in portal vein stage,and the scanning parameters were the same.After scanning,Syngo dual-energy post-processing software of Siemens multi-mode image workstation was used to reconstruct and fuse the 5 mm layer thickness image of the portal vein stage in the reduced dose group by two methods:"optimum contrast(OC)"and"monoenergetic(Mono)".The CT value and SD value of the portal vein trunk and the normal liver parenchyma of images in each group were measured.The contrast to noise ratio(CNR)of theportal vein and the liver parenchyma and portal vein signal to ratio(SNR)were calculated.Results Compared with the normal dose group,there was no statistically significant difference in the subjective score in the reduced dose OC group(P>0.05),but the CNR and SNR of the portal vein trunk in the images were significantly improved(P<0.05).The portal vein CT value and the difference between portal vein and liver parenchyma in the reduced dose Mono group were significantly lower than those in the normal dose group,and the subjective score was the lowest,with statistical differences(P<0.05).Conclusion In the case of reducing the contrast agent dose by 20%,the dual-energy CT reconstruction fusion method can not only reduce the damage of contrast agent to patients,but also significantly improve the lesion display,and improve the consistency of liver enhancement image quality.

Objective To analyze the influencing factors for the knowledge level,cognition willingness and atti-tude of health care workers(HCWs)towards monkeypox.Methods A cross-sectional survey was conducted,from January to April 2023,700 HCWs were randomly selected from a tertiary hospital in Shanghai.Based on a self-de-signed questionnaire,the survey was conducted anonymously through the online platform"Wenjuanxing".Results A total of 612 questionnaires were collected,581 were valid,with a response rate of 87.43％and an effective rate of 94.93％.The mean score of the questionnaire was(128.80±27.70)points,with a score rate of 58.54％.Multiple linear regression analysis showed that there were statistically significant differences in the knowledge level of mon-keypox among HCWs of different ages,occupations,departments,educational levels,years of working experience,professional titles,initiative cognition on monkeypox,and participation in monkeypox-related lectures organized by the units(all P＜0.05).Conclusion HCWs'cognition on monkeypox is at a moderate level.The training of HC-Ws on monkeypox knowledge should be strengthened to improve the emergency response capabilities during mon-keypox outbreaks.

Objective To explore preemptive analgesic effect of preoperative intramural tramadol injection in percutaneous kyphoplasty(PKP)of vertebrae following local anesthesia.Methods From August 2019 to June 2021,118 patients with thora-co lumbar osteoporotic fractures were treated and divided into observation group and control group,with 59 patients in each gruop.In observation group,there were 26 males and 33 females,aged from 57 to 80 years old with an average of(67.69±4.75)years old;14 patients on T11,12 patients on T12,18 patients on L1,15 patients on L2;tramadol with 100 mg was injected intramuscularly half an hour before surgery in observation group.In control group,there were 24 males and 35 females,aged from 55 to 77 years old with an average of(68.00±4.43)years old;19 patients on T11,11 patients on T12,17patients on L1,12 patients on L2;the same amount of normal saline was injected intramuscularly in control group.Observation indicators included operation time,intraoperative bleeding,visual analogue scale(VAS)evaluation and recording of preoperative(T0),intraoper-ative puncture(T1),and working cannula placement(T2)between two groups of patients,at the time of balloon dilation(T3),when the bone cement was injected into the vertebral body(T4),2 hours after the operation(T5),and the pain degree at the time of discharge(T6);adverse reactions such as dizziness,nausea and vomiting were observed and recorded;the record the patient's acceptance of repeat PKP surgery.Results All patients were successfully completed PKP via bilateral pedicle ap-proach,and no intravenous sedative and analgesic drugs were used during the operation.There was no significant difference in preoperative general data and VAS(T0)between two groups(P＞0.05).There was no significant difference in operation time and intraoperative blood loss between the two groups(P＞0.05).VAS of T1,T2,T3,T4 and T5 in observation group were all lower than those in control group(P＜0.05),and there was no significant difference in T6 VAS(P＞0.05).T6 VAS between two groups were significantly lower than those of T0,and the difference was statistically significant(P＜0.05).There was no signifi-cant difference in incidence of total adverse reactions between two groups(P＞0.05).There was a statistically significant differ-ence in the acceptance of repeat PKP surgery(P＜0.05).Conclusion Half an hour before operation,intramuscular injection of tramadol has a clear preemptive analgesic effect for PKP of single-segment thoracolumbar osteoporotic fracture vertebral body under local anesthesia,which could increase the comfort of patients during operation and 2 hours after operation,and improve patients satisfaction with surgery.

Objective To investigate the clinical effect of minimally invasive transforaminal lumbar interbody fusion(Mis-TLIF)technique combined with preoperative position reduction in the treatment of spondylolisthesis and summarize its advan-tages.Methods Between July 2016 and July 2022,60 patients with lumbar isthmic spondylolisthesis were retrospectively ana-lyzed,including 26 males and 34 females,with an average age of(51.32±4.24)years old ranging from 35 to 72 years old.They were divided into observation group and control group according to the operation methods.There were 30 patients in the obser-vation group,including 12 males and 18 females;the age ranged from 35 to 71 years old with an average of(51.80±6.38)years old,the course of disease ranged from 12 to 60 months with an average of(24.17±1.98)months;there were 18 cases of L4 spondylolisthesis and 12 cases of L5 spondylolisthesis;according to Meyerding classification,there were 20 cases of grade Ⅰspondylolisthesis and 10 cases of grade Ⅱ.The observation group was treated with preoperative postural reduction combined with intraoperative reduction assisted minimally invasive transforaminal lumbar fusion via Quadrant channel(Mis-TLIF).There were 30 patients in the control group,including 14 males and 16 females,with an average of(50.00±4.24)years old ranging from 36 to 72 years old;the course of disease ranged from 12 to 60 months with an average of(23.70±1.53)months;there were 16 cases of L4 spondylolisthesis and 14 cases of L5 spondylolisthesis;according to Meyerding classification,there were 19 cases of grade Ⅰ spondylolisthesis and 11 cases of grade Ⅱ.The control group was treated with open transforaminal lumbar interbody fusion(Open-TLIF).The differences of operation time,intraoperative and postoperative blood loss,hospital stay,radiation exposure time and complications between the two groups were analyzed.Visual analogue scale(VAS),Oswestry disability index(ODI)and Japanese Orthopaedic Association(JOA)score were used to evaluate the clinical effect.X-ray and CT were followed up to evaluate the interbody fusion.Results All patients were followed up for 12 months.There was no signifi-cant difference in operation time,VAS of low back pain,slip angle and slip rate between two groups(P＞0.05).The intraoperative and postoperative blood loss in the observation group(165.50±15.56)ml and(59.17±10.59)ml were less than those in the con-trol group(259.33±35.32)ml and(165.33±29.56)ml(P＜0.05).The length of hospital stay in the observation group(3.53±0.68)days was less than that in the control group(5.20±0.41)days(P＜0.05).The intervertebral space height,slip angle,slip rate,ODI,VAS and JOA scores were significantly improved in the two groups at the final follow-up(P＜0.05).There were signifi-cant differences in ODI[(9.93±1.11)％vs(10.93±1.11)％]and JOA[(26.07±1.01)points vs(25.43±1.25)points]between the observation group and the control group at the final follow-up(P＜0.05).Conclusion In the treatment of spondylolisthesis,preoperative position reduction combined with intraoperative reduction assisted Mis-Tlif technique has advantages of less trau-ma,less bleeding and shorter hospitalization period than traditional open surgery.It is a safe and effective technique.