Objective:To explore the radiological protection measures for yttrium-90 ( 90Y)-loaded resin microsphere therapy in clinical application. Methods:The surgical operation process for 90Y-loaded resin microsphere therapy was simulated, involving measurement of ambient dose equivalent rates at various stages: preoperative preparation (dominated by drug package), drug transfer, intraoperative procedures (drug operation and injection), and postoperative care and observation within the hospital. Based on the simulation, the protection measures in clinical application were analyzed. Results:The dose equivalent rate ranged from 0.12 to 0.42 μSv/h around the active chamber and from 1.04 to 3.32 μSv/h in the fume hood. Around the digital subtraction angiography (DSA) room, the maximum dose equivalent rate was 0.78 μSv/h when 90Y and DSA were applied simultaneously and 0.36 μSv/h when 99Tc m and DSA were applied. For the first operating position in the fluoroscopy protection area, the maximum dose equivalent rate was 13.19 μSv/h at 155 cm height when only 90Y was applied, and 315.01 μSv/h at 80 cm height when 90Y and DSA were applied. For the second operating position, the maximum dose equivalent rate was 6.28 μSv/h at 155 cm height when only 90Y was applied and 291.03 μSv/h at the same height when 90Y and DSA were applied. The dose-equivalent rates ranged from 0.11 to 0.58 μSv/h around the dedicated ward for postoperative patients. Conclusions:The existing shielding measures, such as those in the nuclear medicine department and interventional room, meet the radiation protection requirements for 90Y-loaded resin microsphere therapy. However, it is still necessary to conduct a scientific assessment based on the actual situation. Additionally, radiation protection measures and surface contamination treatment should be enhanced during drug operation.

Objective To investigate the related factor underlying the differential vulnerability of inner hair cell(IHC)ribbon synapses to noise exposure.Methods Twenty-eight C57BL/6J mice were randomly divided into the noise exposure group(NED1)and the control group(CTR)with 14 mice in each group.The noise exposure group was exposed to bandpass noise of 2～20 kHz at 103 dB SPL for two hours while the control group was bred in a quiet environment.Before and after noise exposure,auditory brainstem response was conducted to detect the audi-tory function,whole-mount immunofluorescence staining was used to observe the number of inner hair cell ribbon synapses in different turns.The calcium influx of inner hair cells in the apical and middle turn using whole-cell patch clamp recording was analyzed.Furthermore,the immunofluorescence intensity of calpain in inner hair cells from dif-ferent mouse cochlear turns using whole-mount immunofluorescence staining was compared.Western blotting was used to verify that CtBP2 was degraded by calpain.Results After noise exposure,the ABR threshold of 11.3,16.0,22.6,32.0 kHz increased significantly and the number of ribbon synapses of inner hair cells at the middle turn and basal turn of the cochlea decreased significantly.However,whole-cell patch clamp recordings showed that calcium ion channels were fewer but single-channel current was higher at the apical turn of the cochlea.The open probability of calcium ion channels in IHCs showed no significant difference between the apical turn and the middle turn of the cochlea.But the expression level of calpain of the inner hair cells at the middle and basal turn of the basi-lar membrane was significantly higher than that at the apical turn after noise exposure.The western blotting results also showed that CtBP2 was cleaved in a Ca2+-dependent manner by calpain.Conclusion Calpain may be the main related factor that accounts for the vulnerability of ribbon synapses in inner hair cells in the high frequency region of basal membrane.

Objective·To investigate the pathological and physiological changes underlying noise-induced cochlear nucleus damage and the regulating function of astrocytes on the damage,using a combination of morphological analysis,and molecular biology techniques.Methods·Forty-eight male C57BL/6J mice were randomly divided into two groups and exposed to 110 dB SPL(sound pressure level)broadband noise for 2 hours.Auditory brainstem response(ABR)tests were performed on the mice on days 1,7,14,30,and 90 after the noise exposure.Immunofluorescence staining of cochlear nuclear tissue was conducted to observe cochlear nuclear neurons and auditory synapses,as well as astrocyte activation levels.In addition,the damage to the cochlear nuclear neurons and synapses caused by noise was verified through Western blotting.Results·A significant decrease in cochlear nuclear Bushy cells after noise exposure was observed.The Western blotting results showed that there was severe loss of nerve fibers in cochlear nuclear neurons,indicating that noise caused significant damage to cochlear nucleus neurons.Moreover,a significant loss of auditory synapses labeled with vesicular glutamate transporter 1(Vglutl)was observed,which was the severest on day 14 after noise exposure and slowly recovered on day 90.Interestingly,astrocytes in the cochlear nucleus displayed obvious clustering and activation after noise exposure.By staining with glial fibrillary acidic protein(GFAP),most astrocytes were distributed around the cochlear nucleus,granule cell area,and auditory nerve root before noise exposure,and they had a small size.However,on day 14 after noise exposure,a large number of activated astrocytes aggregated in the ventral cochlear nucleus,and they all showed a pattern of growth around the synapses.Conclusion·Noise exposure leads to significant damage in the cochlear nucleus,and it is possible that astrocytes are involved in its damage and repair processes.These findings will provide a crucial foundation for further understanding the mechanisms of sound signal analysis,integration,and neural plasticity in the cochlear nucleus.

Background China's automobile manufacture is a labor-intensive industry, and most of the welding tasks are manual operations. It is often necessary to observe the solder joints during operation, and there are many adverse health outcome-related factors involved in the work process. However, the research on the prevalence and risk factors of work-related musculoskeletal disorders (WMSDs) in the upper back of welders is still insufficient. Objective To explore the prevalence and risk factors of WMSDs in the upper back of welders from an automobile factory. Methods This was a cross-sectional study. A cluster random sampling method was used to select 972 electric welders from an automobile factory as the study subjects. The Musculoskeletal Disorders Questionnaire was used to estimate the prevalence of WMSDs in the upper back in the past year. Results The prevalence rate of WMSDs in the upper back in the welders was 42.2% (410/972). The positive rates of studied occupational risk factors were 72.5% (705/972) for maintaining same posture for a long time, 71.8% (698/972) for bending and twisting for a long time, and 64.7% (629/972) for repetitive trunk movements. The univariate analysis showed that the prevalence rates of WMSDs were significantly different among workers categorized by gender, working age, twisting and/or bending for a long time, working in the same position for a long time, lifting heavy objects in an uncomfortable position, repetitive trunk movements, being unable to exert energy due to discomfort, work involving cold or temperature changes, personnel shortage, no rest between work, working hours per week, and working in an uncomfortable position (P<0.05). The results of multiple logistic regression indicated that female, working in the same position for a long time, working in an uncomfortable position (frequently), lifting heavy objects in an uncomfortable position, and being unable to exert energy due to discomfort were associated with higher risks of reporting WMSDs in the upper back (OR=2.37, 1.46, 1.76, 1.44, and 1.50, respectively, P<0.05); the risk of reporting WMSDs in the upper back increased by 95%, 157%, and 196% for every 10 h increase in weekly working hours (41-50 h, 51-60 h, ≥61 h vs ≤40 h); adequate rest time was associated with a lower risk for WMSDs in the upper back (OR=0.70, 95%CI: 0.49-0.98). Conclusion The prevalence rate of WMSDs in the upper back of welders in the automobile factory is high, and many occupational risk factors are involved. Measures should be taken for intervention and prevention.

AIM: To observe the effect of PCSK9 inhibitors on blood lipid levels and common inflammatory factors in patients with coronary heart disease. METHODS: The clinical data of 201 patients with coronary heart disease who were admitted to the Department of Cardiology of Shanghai East Hospital from April 2020 to June 2021 were retrospectively analyzed. The patients were divided into PCSK9 inhibitor treatment group (101 cases: statin + PCSK9 inhibitor) and control group (100 cases: statin treatment only) according to their medication status. Blood lipids, blood routine, CRP and FIB were re-examined after 1 month of treatment. The changes of blood lipids and inflammatory factors before and after treatment were compared. RESULTS: Before treatment, there was no significant difference in blood lipids, blood routine, CRP and FIB between the two groups (P> 0.05). The levels of sdLDL and Lp(a) were significantly decreased (P< 0.05); the levels of WBC, CRP, N and FIB were significantly decreased (P< 0.05). Compared with the control group, the levels of TC, HDL, LDL-C, CRP and FIB in the PCSK9 inhibitor group were significantly changed (P< 0.05), and the results were statistically significant. CONCLUSION: PCSK9 inhibitors can not only reduce LDL-C levels, but also reduce Lp(a) levels. PCSK9 inhibitors can reduce CRP and FIB levels, suggesting that it can partially improve inflammation in peripheral blood in patients with coronary heart disease.

Objective:To investigate drug resistance gene in Mycoplasma pneumoniae(MP) and the distribution of 13 respiratory pathogens in bronchoalveolar lavage fluid(BALF) of children with Mycoplasma pneumoniae pneumonia(MPP).Methods:A total of 100 BALF of children with MPP in Peking University Third Hospital and Peking University First Hospital from January 2018 to January 2019 were collected.Fluorogenic quantitative PCR was used to detect nucleic acid and it′s drug resistance gene of MP and multiple PCR method was adopted to detect influenza A virus, influenza A virus-H 1N 1, influenza A virus-H 3N 2, influenza B, human parainfluenza virus, adenovirus, human bocavirus, human rhinovirus, Chlamydia pneumoniae, human metapneumovirus, MP, human coronavirus, and respi-ratory syncytial virus gene, and the results were compared by using Chi square test. Results:In 100 BALF samples, MP and drug resistance gene were detected by fluorogenic quantitative PCR.Totally, 83 cases (83.00%) were MP positive and 78 cases (93.98%) were drug resistant.All of them had the point mutations A2063G in V region of 23S rRNA domain.A total of 13 kinds of respiratory pathogens were detected by multiplex PCR method, and 89 cases (89.00%) were positive.Totally, 79 cases (79.00%) were MP positive, of which 74 cases (74.00%) detected only MP, and 5 cases (5.00%) detected MP combined with other pathogens.Other pathogens were detected in 10 cases (10.00%). The virus detection rate of 0-4 years old group was higher than that of >4-6 years old group ( P=0.042) and >6 years old group ( P=0.002), and the differences were statistically significant. Conclusions:MP can be detected in most BALF samples of MPP children, the drug resistance phenomenon is serious, and the main point mutation is A2063G.There were other respiratory pathogens and 2 or 3 pathogens were detected in a small number of BALF samples.

Objective:To study the relationship between zoledronic acid (ZOL) and vascular endothelial growth factor (VEGF) conformation so as to reveal the mechanism of bisphosphonates inhibiting angiogenesis.Methods:The binding structures of ZOL and VEGF were preprocessed and the molecular dockings were simulated through AutoDockTools, Discovery studio4 and AutoDockVina. The best binding conformation was accurately screened. The effects of various concentrations of ZOL (group A was 0 μmol/L, groups B, C and D were 25, 50 and 100 μmol/L, respectively) on human umbilical vein endothelial cell (HUVEC) proliferation, angiogenesis and angiogenic molecules were detected by using cell counting kit-8 (CCK-8) in vivo and in vitro angiogenesis, immunofluorescence and Western blotting. Results:There was a ZOL binding site on the target protein VEGF conformation. The affinity was -5.2 kcal/mol. This binding site consisted of the hydrophobic region composed of amino acids Cys26, 51, 57, etc. and the hydrogen bond binding region of the A chain (ASP34, SER50) and B chain (CYS61, 68, LEU66, GLY59). The results of CCK-8 showed that the levels of value A in groups B, C and D were significantly lower than that in group A at each time point from 3 to 6 days ( P<0.05). In vitro vascular experiments demonstrated that the numbers of budding in groups B, C and D [(208±28), (151±21) and (62±9), respectively] were significantly lower than that in group A (276±30) ( P<0.05). In vivo vascular experiments displayed that the ratio of Matrigel gel/plasma fluorescence in group A (0.003 1±0.000 3) was significantly higher than those in group B (0.002 1±0.000 2), group C (0.001 6±0.000 2) and group D (0.000 6±0.000 1) ( P<0.05). The results of Western blotting revealed that the expression of VEGF in groups B, C and D [(0.72±0.11), (0.41±0.07) and (0.24±0.04), respectively] were significantly lower than that in group A (1.01±0.02) ( P<0.05), and the expression levels of hypoxia-inducible factor-1α (HIF-1α) in groups B, C and D [(0.68±0.09), (0.55±0.06) and (0.43±0.08), respectively] were significantly lower than that in group A (0.96±0.04) ( P<0.05). Conclusions:ZOL could inhibit cell proliferation, in vivo and in vitro vascularization and expression of VEGF/HIF-1α. The binding site of ZOL with the conformation of VEGF was located in the hydrophobic region and hydrogen-bonding region of amino acids. Designing an antagonist targeting this site might potentially alleviate the effect of ZOL in inhibiting angiogenesis.

Objective:To investigate the effect of six degree of freedom (6-DOF) bed combined with cone beam computed tomography (CBCT) in the on-line correction of setup errors in patients with primary rectal cancer.Methods:The clinicopathological data of 17 patients with primary rectal cancer in Department of Radiotherapy, Third Hospital of Peking University from July 2013 to January 2014 were collected. There were 14 males and 3 females, a median age of 65 years. The difference of CBCT and 6-DOF bed combined with CBCT online correction of patients with positioning error were retrospectively analyzed.Results:Before position correction, the first CBCT verification of setup errors in the three translation directions including X (left and right), Y (in and out) and Z (up and down) directions were (0.06±0.25) cm, (0.13±0.40) cm and (-0.28±0.31) cm, respectively. The setup errors of RX (rotation pitch), RY(rolling) and RZ (left and right rotation) directions were (0.62±1.15)°, (-0.19±0.99)°, and (-0.34 ± 0.84)°, respectively . After correction of IGRT combined with six freedom of bed, the setup errors of translation X, Y and Z were (0.01±0.09) cm, (-0.01±0.05) cm and (-0.03±0.08) cm, respectively, and the setup errors of rotation RX, RY and RZ directions were (-0.16±0.40)°, (0.36±0.31)°and (-0.01±0.25)°, respectively. There were significant differences in translation direction (X, Y and Z direction) and rotation direction (Rx, RY and RZ) before and after 6-DOF bed combined with CBCT correction (all P<0.05). In the translation direction, the higher frequency range of Z-direction error value was 0.20-0.79 cm. In the rotation direction, the frequency range of error in Rx direction was 0.20°-2.99°. There was no significant difference between bone mode and gray scale model registration ( P>0.05). With the progress of radiotherapy, the setup errors of X, Z, Rx, RY and RZ directions increased except Y direction. Conclusions:In radiotherapy, six freedom bed combined with CBCT is helpful to correct the setup errors of patients with primary rectal cancer. Six freedom bed may be used to correct the setup errors of patients with primary rectal cancer online. Image-guided radiation therapy (IGRT) is recommended for bone pattern registration in patients with rectal cancer.

Objective:To investigate the effect of six degree of freedom (6-DOF) bed combined with cone beam computed tomography (CBCT) in the on-line correction of setup errors in patients with primary rectal cancer.Methods:The clinicopathological data of 17 patients with primary rectal cancer in Department of Radiotherapy, Third Hospital of Peking University from July 2013 to January 2014 were collected. There were 14 males and 3 females, a median age of 65 years. The difference of CBCT and 6-DOF bed combined with CBCT online correction of patients with positioning error were retrospectively analyzed.Results:Before position correction, the first CBCT verification of setup errors in the three translation directions including X (left and right), Y (in and out) and Z (up and down) directions were (0.06±0.25) cm, (0.13±0.40) cm and (-0.28±0.31) cm, respectively. The setup errors of RX (rotation pitch), RY(rolling) and RZ (left and right rotation) directions were (0.62±1.15)°, (-0.19±0.99)°, and (-0.34 ± 0.84)°, respectively . After correction of IGRT combined with six freedom of bed, the setup errors of translation X, Y and Z were (0.01±0.09) cm, (-0.01±0.05) cm and (-0.03±0.08) cm, respectively, and the setup errors of rotation RX, RY and RZ directions were (-0.16±0.40)°, (0.36±0.31)°and (-0.01±0.25)°, respectively. There were significant differences in translation direction (X, Y and Z direction) and rotation direction (Rx, RY and RZ) before and after 6-DOF bed combined with CBCT correction (all P<0.05). In the translation direction, the higher frequency range of Z-direction error value was 0.20-0.79 cm. In the rotation direction, the frequency range of error in Rx direction was 0.20°-2.99°. There was no significant difference between bone mode and gray scale model registration ( P>0.05). With the progress of radiotherapy, the setup errors of X, Z, Rx, RY and RZ directions increased except Y direction. Conclusions:In radiotherapy, six freedom bed combined with CBCT is helpful to correct the setup errors of patients with primary rectal cancer. Six freedom bed may be used to correct the setup errors of patients with primary rectal cancer online. Image-guided radiation therapy (IGRT) is recommended for bone pattern registration in patients with rectal cancer.

Objective To investigate the short-and mid-term prognosis and its influencing factors of Kasai portoenterostomy for type Ⅲ biliary atresia.Methods 220 infants with type Ⅲ biliary atresia who underwent Kasai surgery at Capital Pediatric Institution from Jan 2014 to June 2017 were retrospectively reviewed.There were 88 males and 132 females,with an average age at operation (60 ±23) d.The followup time ranged from 12 to 53 months.Results The survival rate with native liver (SNL) at 1,2,and 3 years after Kasai operation were 65％,59.6％,and 57.0％,respectively.The clearance rate of jaundice within 3 months after Kasai was 50.5％;3-year SNL of infants whose jaundice disappeared or did not after operation were 86.8％ and 27.1％ (P ＜ 0.05).The overall incidence of cholangitis was 60％.The clearance rate of jaundice in children with or without cholangitis was 55.3％ and 43.2％,while the 3-year SNL were 62.4％ and 49.6％,respectively (P ＞ 0.05).Conclusion The 3-year survival rate on their native liver after Kasai operation in infants with type Ⅲ biliary atresia can reach up to 57％.The clearance of jaundice within 3 months post-operation is the main factor affecting prognosis.The age at surgery and the occurrence of cholangitis do not affect the survival rate of native liver in the short-and mid-term prognosis.