The"4+4"Medical Doctor(MD)Pilot Program at PUMC:Implementation,Performance,and Prospects

Peking Union Medical College(PUMC)launched the"4+4"Medical Doctor(MD)pilot program in 2018,admitting students with non-medical backgrounds from top universities,aligning with national medical talent training policies to foster diverse and eager learners in medicine.On the occasion of the graduation of the first class of the"4+4"MD pilot class at PUMC in 2023,we reviewed the teaching reform in the pilot program and carried out a systematic survey and interviews with students,faculties,and management staff of the pilot class.This article reports on the measures taken by the pilot class at PUMC in enrollment and curriculum setting,and demonstrates the achievements of the pilot class in terms of student academic background structure,knowledge acquisition and skill learning,scientific research ability,and course evaluation.The results indicated that the pilot class had met the national demand for the"Medicine+X"talent training model.More specifically,with a diverse academic backgrounds,the pilot class graduates had academic levels comparable to the eight-year medical education graduates,and their scientific research abilities were satisfactory.The pilot program at PUMC will optimize the curriculum setting,strengthen the construction of faculty,learning resources,and teaching facilities,and reform the academic evaluation methods,thus deepening the reform of medical education and improving the"4+4"MD program as a novel medical education model.

Predicting short-term major postoperative complications in intestinal resection for Crohn’s disease:A machine learning-based study

BACKGROUND Due to the complexity and numerous comorbidities associated with Crohn’s disease(CD),the incidence of postoperative complications is high,significantly impacting the recovery and prognosis of patients.Consequently,additional stu-dies are required to precisely predict short-term major complications following intestinal resection(IR),aiding surgical decision-making and optimizing patient care.AIM To construct novel models based on machine learning(ML)to predict short-term major postoperative complications in patients with CD following IR.METHODS A retrospective analysis was performed on clinical data derived from a patient cohort that underwent IR for CD from January 2017 to December 2022.The study participants were randomly allocated to either a training cohort or a validation cohort.The logistic regression and random forest(RF)were applied to construct models in the training cohort,with model discrimination evaluated using the area under the curves(AUC).The validation cohort assessed the performance of the constructed models.RESULTS Out of the 259 patients encompassed in the study,5.0%encountered major postoperative complications(Clavien-Dindo≥III)within 30 d following IR for CD.The AUC for the logistic model was 0.916,significantly lower than the AUC of 0.965 for the RF model.The logistic model incorporated a preoperative CD activity index(CDAI)of≥220,a diminished preoperative serum albumin level,conversion to laparotomy surgery,and an extended operation time.A nomogram for the logistic model was plotted.Except for the surgical approach,the other three variables ranked among the top four important variables in the novel ML model.CONCLUSION Both the nomogram and RF exhibited good performance in predicting short-term major postoperative complic-ations in patients with CD,with the RF model showing more superiority.A preoperative CDAI of≥220,a di-minished preoperative serum albumin level,and an extended operation time might be the most crucial variables.The findings of this study can assist clinicians in identifying patients at a higher risk for complications and offering personalized perioperative management to enhance patient outcomes.

Effects of the properties of FCCS on the removing of catalyst particles from FCCS under a DC electrostatic field

Catalytic cracking is the main method to lighten heavy crude oil,this process can produce high quality oil products such as gasoline and diesel,but also produces a large amount of fluid catalytic cracking slurry(FCCS).The catalyst particles in FCCS seriously restrict the secondary processing of FCCS and need to be removed,and the properties of Fccs is an important factor that affects the removal efficiency of the catalyst particles.Based on the"effective contact point"model proposed by the research group,this study further proposed the"electrostatic separation efficiency calculation"model.In this model,since Fccs has a uniform distribution of catalyst particles,the ratio of the number of catalyst particles can be expressed as the ratio of area to achieve the calculation of separation efficiency.Then the catalyst removal efficiency under different viscosity was analyzed,thus verifying the feasibility of this model.The effects of temperature and mass ratio of four components on the viscosity of FccS were investigated respectively,then the effects of temperature and four components'mass ratio on the electrostatic sep-aration can be directly converted into the effect of viscosity on the electrostatic separation efficiency.All the results show the electrostatic separation efficiency decreases with increasing viscosity,and the best separationtemperatureis120℃.

顺铂配置过程中的残留量分析

目的通过检测顺铂配药过程中细胞毒性药物的残留情况,指导有效的个人防护措施。方法选取配置人员的手套、口罩及残留环境空气,以高效液相色谱法检测残留化疗药物的浓度。结果在1~200μg/ml范围内,顺铂的质量浓度与峰面积呈线性关系(r=0.999)。配置顺铂注射液的支数越多,外层手套上顺铂的残留量越大。外层口罩上的顺铂残留量较小,仅当支数为120支时检测出微量残留。内层手套和空气中残留浓度检测均低于下限。结论该文为静脉配置中心集中化疗配置过程提供了有效个人防护的方法,检测过程灵敏有效且干扰小。

Cyclopexy versus vitrectomy combined with intraocular tamponade for treatment of cyclodialysis

AIM:Tocomparetheeffectsandcomplicationsof direc cyclopexy (DC) versus vitrectomy, endophotocoagulation, and gas/silicone oil endotamponade (VEE) treatment in patients with cyclodialysis and persistent hypotony.METHODS: This is a prospective, comparative, non-randomized clinical trial which includes 52 patients with cyclodialysis and persisting hypotony. Fifty-two patients suffering from cyclodialysis and persistent hypotony in one eye were divided into 2 groups (groups DC and VEE) and treated, respectively, with direct cyclopexy or vitrectomy, endophotocoagulation, and gas/silicone oil endotamponade. The patients were followed up for 12 months. Assessments included best corrected visual acuity (BCVA), intraocular pressure (IOP), anterior chamber depth (ACD), anterior chamber volume (ACV) and subjective rating of the pain caused by the treatments.RESULTS: After a follow-up of 12 months, significan improvement was seen in postoperative mean BCVA, IOP, ACD and ACV in both treatment groups (which were not significantly different from each other). The success rates for the treatments were not significantly different (DC: 50.0% vs VEE: 62.5% , P =0.383). Postoperative morbidity of cataract and subjective pain rating were significantly higher in the VEE group vs the DC group (P =0.003 and P 【0.001 respectively).CONCLUSION: DC and VEE were effective surgica procedures in treating patients with cyclodialysis and persistent hypotony. Patients had better tolerance to DC treatment and VEE was more likely lead to cataract complications. Taking into consideration the ease of the operation, success rate, and patient comfort, DC treatment seems preferable to VEE treatment in patients with simple cyclodialysis. While VEE has the advantage of treating patients with cyclodialysis combined with vitreous hemorrhage.

Differentiation potential of human adipose tissue derived stem cells into photoreceptors through explants culture and enzyme methods

AIM： To investigate the retinal photoreceptor differentiation potential of human orbital adipose tissue-derived stem cells （ADSCs） generated by enzyme （EN） and explant （EX） culture methods.METHODS： We investigated potentials of human orbital ADSCs to differentiate into photoreceptors through EN and EX culture methods. EN and EX orbital ADSCs were obtained from the same donor during rehabilitative orbital decompression, and then were subject to a 3-step induction using Noggin, DKK-1, IGF-1 and b-FGF at different time points for 38d. Stem cell, eye-field and photoreceptor-related gene and protein markers were measured by reverse transcription-polymerase chain reaction （RT-PCR） and immunofluorescent （IMF） staining.RESULTS： Both EX and EN orbital ADSCs expressed CD133, a marker of cell differentiation. Moreover, PAX6 and rhodopsin, markers of the retinal progenitor cells, were detected from EX and EN orbital ADSCs. In EX orbital ADSCs, PAX6 mRNA was detected on the 17th day and then the rhodopsin mRNA was detected on the 24th day. In contrast, the EN orbital ADSCs expressed PAX6 and rhodopsin mRNA on the 31st day. EX orbital ADSCs expressed rhodopsin protein on the 24th day, while EN orbital ADSCs expressed rhodopsin protein on the 31st day. CONCLUSION： Orbital ADSCs isolated by direct explants culture show earlier and stronger expressions of markers towards eye field and retinal photoreceptor differentiation than those generated by conventional EN method.

Protective role of retinoid X receptor in H9c2 cardiomyocytes from hypoxia/reoxygenation injury in rats

BACKGROUND: Retinoid X receptor(RXR) plays a central role in the regulation of intracellular receptor signaling pathways. The activation of RXR has protective effect on H2O2-induced apoptosis of H9c2 ventricular cells in rats. But the protective effect and mechanism of activating RXR in cardiomyocytes against hypoxia/reoxygenation(H/R)-induced oxidative iniury are still unclear.METHODS: The model of H/R injury was established through hypoxia for 2 hours and reoxygenation for 4 hours in H9c2 cardiomyocytes of rats. 9-cis-retinoic acid(9-cis RA) was obtained as an RXR agonist, and HX531 as an RXR antagonist. Cultured cardiomyocytes were randomly divided into four groups: sham group, H/R group, H/R+9-cis RA-pretreated group(100 nmol/L 9-cis RA), and H/R+9-cis RA+HX531-pretreated group(2.5 μmol/L HX531). The cell viability was measured by MTT, apoptosis rate of cardiomyocytes by flow cytometry analysis, and mitochondrial membrane potential(ΔΨm) by JC-1 fluorescent probe, and protein expressions of Bcl-2, Bax and cleaved caspase-9 with Western blotting. All measurement data were expressed as mean±standard deviation, and analyzed using one-way ANOVA and the Dunnett test. Differences were considered signif icant when P was <0.05.RESULTS: Pretreatment with RXR agonist enhanced cell viability, reduced apoptosis ratio, and stabled ΔΨm. Dot blotting experiments showed that under H/R stress conditions, Bcl-2 protein level decreased, while Bax and cleaved caspase-9 were increased. 9-cis RA administration before H/R stress prevented these effects, but the protective effects of activating RXR on cardiomyocytes against H/R induced oxidative injury were abolished when pretreated with RXR pan-antagonist HX531.CONCLUSION: The activation of RXR has protective effects against H/R injury in H9c2 cardiomyocytes of rats through attenuating signaling pathway of mitochondria apoptosis.

Effects of electroacupuncture at auricular concha area on the circadian rhythm of melatonin secretion in p-chlorophenylalanine-induced insomnia rats

Backgroud:The electroacupuncture of auricular concha area(EA-ACR)proved to have a good regulatory effect on insomnia and the release of melatonin,which is most closely related to sleep.However,there is little research to demonstrate the relationship between EA-ACR and melatonin.The objective of present study is to observe the effects of EA-ACR on the circadian rhythm of melatonin secretion in p-chlorophenylalanine(PCPA)-induced insomnia rats.Methods:The study divided 36 male Sprague-Dawley rats randomly into three groups:12 in blank group,12 in model group,and 12 in EA-ACR group.By using PCPA intraperitoneal injection for 2 days,insomnia model was established.EA-ACR group was treated for 28 days.We observed the effects of EA-ACR on the rats'behavioral changes,open-field test and weight during the experiment.After the experiment,the rat tail and heart blood were collected,and the melatonin was detected by enzyme-linked immunosorbent assay.Results:Compared with the blank group,28–30 hours after PCPA intraperitoneal injection,the circadian rhythm of sleep and the total sleep time of model rats decreased.Compared with the model group,electrical stimulation in the ear concha region could effectively reverse the behavioral changes of rats,and increase the trend of weight growth(P=0.010),the crossing score(P=0.014),vertical motion score(P=0.015)and the level of plasma melatonin secretion(P=0.020)with the trend showing a rhythmic pattern(0–60 minutes upward,60–120 minutes downward,120–150 minutes upward).Conclusion:EA-ACR can improve the quality of life(weight),ameliorate exploring irritable and anxiety behaviors in PCPA-induced insomnia rats.The underlying effects of EA-ACR may be excited on the circadian rhythm of melatonin secretion in PCPA-induced insomnia rats.

An easily-prepared impedance matched Josephson parametric amplifier

An impedance matched parametric amplifier(IMPA)with Josephson junctions is fabricated and characterized.A hybrid structure containing coplanar and strip structures is implemented to realize an impedance taper line and a plate capacitor in an LC nonlinear resonator based on Josephson junctions.The upper plate of the capacitor is isolated with SiNx without grounding as well as the strips.Such easily-prepared designs greatly reduce the requirements for lithography alignment and precision,which makes the fabrication process more reliable.The experimental results show that in such IMPA a gain higher than 25 dB with a bandwidth of about 100 MHz can be obtained.This broadband amplifier operates close to the quantum limit.By adjusting the working point,a higher bandwidth of about 400 MHz can be obtained with a gain of about 17 dB.

Compact NbN resonators with high kinetic inductance

We design and fabricateλ/2 coplanar waveguide NbN resonators,the thickness and length of which are only several nanometers and hundred microns,respectively.The quality factor of such compact resonators can reach up to 7.5×10~4 at single photon power level at 30 m K with the resonance frequency around 6.835 GHz.In order to tune the resonant frequency,the resonator is terminated to the ground with a dc-SQUID.By tuning the magnetic flux in the dc-SQUID,the effective inductance of the dc-SQUID is varied,which leads to the change in the resonant frequency of the resonator.The tunability range is more than 30 MHz and the quality factor is about 3×10~3.These compact and tunable NbN resonators have potential applications in the quantum information processing,such as in the precision measurement,coupling and/or reading out the quantum states of qubits.

Treatment of insomnia by differentiation of yang deficiency syndrome

Insomnia has become one of the common clinical diseases.In recent years,it has been found that patients with insomnia of Yang deficiency type are more and more common,and the trend of rejuvenation gradually appears,which seriously affects the normal progress of people's life,work and study.Clinical treatment through syndrome differentiation,mainly from the heart,spleen,kidney three viscera yang deficiency,on the basis of the warm yang method to add Qianzhen tranquilizing products,and pay attention to multiple organs as diseases,add moisture,blood The qi thing,while not forgetting the psychological counseling,adjusting the body and mind,and achieving a certain clinical effect,can provide ideas for the treatment of this disease.

Influence of filler characteristics on particle removal in fluid catalytic cracking slurry under an alternating electric field

The characteristics of the packing material under an alternating electric field are an important factor in the removal of FCCS particles.In this study,the electric field distribution of a separation unit consisting of packed spheres under an alternating electric field is simulated,and the movement mechanism of catalyst particles is analysed.An"effective contact point"model is derived to predict the adsorption of filler contact points on catalyst particles under the alternating electric field,and the model is validated by simulations and experiments.The numerical calculation and experimental results indicate that the electrical properties of the filler spheres,the filler angleθ,and the frequency f of the alternating electric field affect the adsorption of catalyst particles.As the frequency of the electric field increases,the particle removal efficiency of the high-conductivity filler(silicon carbide)increases and then settles,and the separation efficiency of the low-conductivity filler(glass,zirconia)is not sensitive to the change in electric field frequency.

Clinico-neuropathological features of isocitrate dehydrogenase 2 gene mutations in lower-grade gliomas

Background:Mutations in the isocitrate dehydrogenase 1(IDH1)and IDH2 genes are important for both the integrated diagnosis and the prognosis of diffuse gliomas.The p.R132H mutation of IDH1 is the most frequently observed IDH mutation,while IDH2 mutations were relatively rarely studied.The aim of the study was to determine the pathological and genetic characteristics of lowergrade gliomas that carry IDH2 mutations.Methods:Data from 238 adult patients with lower-grade gliomas were retrospectively analyzed.The status of IDH1/2 gene mutations,telomerase reverse transcriptase(TERT)promoter mutations,O^6-methylguanine-DNA-methyltransferase(MGMT)promoter methylation,1p/19q co-deletion and the expressions of IDH1 R132H,alpha-thalassemia X-linked mental retardation,and p53 were evaluated.Progression-free survival(PFS)and overall survival(OS)were calculated via Kaplan-Meier estimation using the log-rank test.Results:Totally,71%(169/238)of patients were positive for IDH mutations,including 12 patients harboring mutations in IDH2.Among the 12 patients with IDH2 mutations,ten patients harbored the R172K mutation,one patient harbored the R172S mutation and one harbored the R172W mutation.Of these,11 tumors occurred in the frontal lobe and showed morphology typical of oligodendroglioma.The proportion of grade II tumors was higher than that of grade III tumors in IDH2 mutant-gliomas.IDH2 mutations were frequently associated with TERT promoter mutations,1p/19q co-deletion and MGMT promoter methylation.IDH2 mutations were associated with better outcomes compared with IDH wild-type gliomas(P<0.05).However,the PFS and OS did not differ from that of IDH1 mutant patients(P=0.95 and P=0.60,respectively).Conclusions:IDH2 mutations are more frequent in oligodendrogliomas and associated with a better prognosis.IDH2 mutations may segregate in distinct clinico-pathological and genetic subtypes of gliomas,and therefore may merit routine investigation.

Safety and efficacy of thalidomide in patients with transfusiondependentβ-thalassemia:a randomized clinical trial

Thalidomide inducesγ-globin expression in erythroid progenitor cells,but its efficacy on patients with transfusion-dependentβ-thalassemia(TDT)remains unclear.In this phase 2,multi-center,randomized,double-blind clinical trial,we aimed to determine the safety and efficacy of thalidomide in TDT patients.A hundred patients of 14 years or older were randomly assigned to receive placebo or thalidomide for 12 weeks,followed by an extension phase of at least 36 weeks.The primary endpoint was the change of hemoglobin(Hb)level in the patients.The secondary endpoints included the red blood cell(RBC)units transfused and adverse effects.In the placebo-controlled period,Hb concentrations in patients treated with thalidomide achieved a median elevation of 14.0(range,2.5 to 37.5)g/L,whereas Hb in patients treated with placebo did not significantly change.Within the 12 weeks,the mean RBC transfusion volume for patients treated with thalidomide and placebo was 5.4±5.0 U and 10.3±6.4 U,respectively(P<0.001).Adverse events of drowsiness,dizziness,fatigue,pyrexia,sore throat,and rash were more common with thalidomide than placebo.In the extension phase,treatment with thalidomide for 24 weeks resulted in a sustainable increase in Hb concentrations which reached 104.9±19.0 g/L,without blood transfusion.Significant increase in Hb concentration and reduction in RBC transfusions were associated with nonβ0/β0 and HBS1L-MYB(rs9399137 C/T,C/C;rs4895441 A/G,G/G)genotypes.These results demonstrated that thalidomide is effective in patients with TDT.

新型口服抗凝血剂在心房颤动患者中胃肠道出血和颅内出血的风险分析:系统回顾和网络meta分析（英文）

目的:评估新型口服抗凝药物在心房颤动患者中胃肠道出血和颅内出血的风险。创新点:首次用网络meta分析的方法评估新型口服抗凝血剂在心房颤动患者中胃肠道出血和颅内出血的风险。方法:我们搜集了20个随机控制试验共91 671位使用抗凝、抗血小板药物或安慰剂的房颤患者。采用贝叶斯网络meta分析,使用马尔可夫链蒙特卡罗方法模拟了比值比(OR)和95%置信区间(CI)。结论:通过与贝叶斯模型的间接比较证实,阿司匹林+氯吡格雷相比安慰剂大大增加房颤患者胃肠道出血的风险(OR 0.33,95%CI 0.01~0.92)。华法林与新型口服抗凝药物相比,大大增加了颅内出血风险,其中与依度沙班30 mg相比OR 3.42,95%CI 1.22~7.24,与达比加群11 mg相比OR 3.56,95%CI 1.10~8.45。我们进一步排名发现胃肠道出血风险最低的新型口服抗凝血剂是阿哌沙班5 mg,颅内出血最低的是阿哌沙班5 mg、达比加群110 mg和依度沙班30 mg。

View-Aware Image Object Compositing and Synthesis from Multiple Sources

Image compositing is widely used to combine visual elements from separate source images into a single image. Although recent image compositing techniques are capable of achieving smooth blending of the visual elements from different sources, most of them implicitly assume the source images are taken in the same viewpoint. In this paper, we present an approach to compositing novel image objects from multiple source images which have different viewpoints. Our key idea is to construct 3D proxies for meaningful components of the source image objects, and use these 3D component proxies to warp and seamlessly merge components together in the same viewpoint. To realize this idea, we introduce a coordinate- frame based single-view camera calibration algorithm to handle general types of image objects, a structure-aware cuboid optimization algorithm to get the cuboid proxies for image object components with correct structure relationship, and finally a 3D-proxy transformation guided image warping algorithm to stitch object components. We further describe a novel application based on this compositing approach to automatically synthesize a large number of image objects from a set of exemplars. Experimental results show that our compositing approach can be applied to a variety of image objects, such as chairs, cups, lamps, and robots, and the synthesis application can create novel image objects with significant shape and style variations from a small set of exemplars.

Mechanical Assembly Packing Problem Using Joint Constraints

The three-dimensional packing problem is generally on how to pack a set of models into a given bounding box using the smallest packaging volume. It is known as an NP-hard problem. When discussing the packing problem in mechanical field, the space utilization of a mechanism is low due to the constraint of mechanical joints between different mechanical parts. Although such a situation can be improved by breaking the mechanism into components at every joint, it burdens the user when reassembling the mechanism and may also reduce the service life of mechanical parts. In this paper, we propose a novel mechanism packing algorithm that deliberately considers the DOFs （degrees of freedom） of mechanical joints. With this algorithm, we construct the solution space according to each joint. While building the search tree of the splitting scheme, we do not break the joint, but move the joint. Therefore, the algorithm proposed in this paper just requires the minimal number of splits to meet the goal of space utilization. Numerical examples show that the proposed method is convenient and efficient to pack three-dimensional models into a given bounding box with high space utilization.

Clinicopathological features of inflammatory demyelinating diseases in biopsy

Inflammatory demyelinating diseases(IDD)of the central nervous system(CNS)occur throughout the world and are the leading cause of nontraumatic neurological disability in young adults.[1]Early diagnosis of IDD allows prompt immunotherapies that minimize relapse,disabilities and mortality.[2]Multiple sclerosis(MS)is the most frequent IDD in adults.The histological characteristics of chronic MS lesions are well known to neuropathologists;however,diagnosing an inflammatory demyelinating process in biopsy may be challenging since the specimens are frequently small and often represent only parts of a larger lesion.[3]Furthermore,the histopathological hallmarks of acute MS differ fundamentally from the well-known characteristics of chronic demyelinated plaques observed in autopsies.[3]Kuhlmann et al[4]recently proposed a new histological classification system for MS lesions.Whether this new classification system corresponds to clinical manifestations and thus reflects the temporal multiplicity of MS and whether it can be applied to all IDD cases remain to be further studied.

New Technique:Sketch-based rotation editing

We present a sketch-based rotation editing system for enriching rotational motion in keyframe animations. Given a set of keyframe orientations of a rigid object, the user first edits its angular velocity trajectory by sketching curves, and then the system computes the altered rotational motion by solving a variational curve fitting problem. The solved rotational motion not only satisfies the orientation constraints at the keyframes, but also fits well the user-specified angular velocity trajectory. Our system is simple and easy to use. We demonstrate its usefulness by adding interesting and realistic rotational details to several keyframe animations.

Theoretical Exploration of Alloying Effects on Stabilities and Mechanical Properties ofγʹPhase in Novel Co–Al–Nb-Base Superalloys

The new developedγ/γʹCo–Al–Nb-base alloys show great potentials as high-temperature materials.However,finding appropriate compositions to improve performance of alloys still poses a great challenge to the development of Co–Al–Nb-base alloys.Motivated by the lack of alloying effects on fundamental properties of criticalγʹphase,we systematically performed a theoretical investigation on the effect of alloying elements TM(TM:Ti,V,Cr,Zr,Mo,Ta,W,Re,and Ru)on phase stabilities and mechanical properties of L1_(2)-typeγʹ(Co,Ni)_(3)(Al,Nb).By analyzing the stability ofγʹphase with respect to its competitive B2 and D0_(19) phases,the results shown that Ti,V,and Cr enhance the L1_(2) stability and widen the L1_(2)–D0_(19) energy barrier,in which V yields the maximum influence.The analysis of electronic structure indicated that the alternation of valence electrons at fermi level would be the atomic origin for doping TM inγʹphase.The calculated results of mechanical properties shown that V and Cr are expected to be optimal dopant for enhancing the strength and the ductility ofγʹphase.The addition of Ta is also beneficial for enhancing the strength at the slight expense of ductility ofγʹphase.By drawing the mechanical maps,the preferred composition range for the phases with desired properties is roughly demarcated in theory for the multi-addition of V/Cr and V/Ta inγʹphase.The findings would be useful for optimizing the performance of novelγ/γʹCo–Al–Nb-base superalloys.