Objective To establish a new method to analyze the position accuracy of multileaf collimator (MLC) in the dynamic mode.Methods The MLC test sequence was created in a field,where intentional leaf positional errors ranging from 0.1 to 1 mm per centimeter were introduced.In order to establish the relationship between the ion chamber readings and leaf position,whose slope indicated the leaf position error per centimeter,a two-dimensional ion chamber array was used to measure absorbed dose while leaves were moving at dose rates of 100,300 and 600 MU/min,respectively.For routine test,leaf position error was easily found via dose profile in y direction of the field created by dynamic leaves,where the position error could be quantitatively calculated as the slope of absorbed dose line of x direction of the same field.Results The error of 0.2 mm or more per centimeter was obviously shown through y dose profile.The calibration curve was linear at different dose rates.At 600 MU/min,a 0.1 mm leaf position error corresponded to a slope variation of 0.74％,and the differences between the tested errors and the introduced errors were within 0.1 mm.Conclusions The simple and reliable method is helpful to establish the intensity modulated radiation therapy (IMRT) quality control (QC) system.

Objective To evaluate the potential feasibility of γ-H2AX foci as a biodosimetry after exposure to ionizing radiation by comparing DNA double-strand break repair kinetics in rat blood lymphocytes with that in human lymphocytes.Methods Peripheral blood lymphocytes separated from Sprague-Dawley(SD) male rats and healthy adults were exposed to γ-rays,and some rats were also subjected to total body irradiation.The inductions of DNA repair-related foci of γ-H2AX,pATM (S1981) and pDNA-PKcs (T2609) were detected with immunofluorescence staining technique at different time points post-irradiation,and the status of their co-localization was analyzed.Results The induction kinetics of γ-H2AX foci in rat lymphocytes was similar to that observed in human lymphocytes.The frequencies of γ-H2AX foci peaked at 30 min after γ-ray irradiation (trst =62.64,th =28.52,P ＜ 0.05),then decreased rapidly after 6 h post-irradiation (trat =45.96,th =14.80,P ＜0.05),and the residual foci number remained only about 3％-8％ of its maximal value at 24 h post-irradiation.At 30 min after γ-ray irradiation,the frequencies of pATM (S1981) and pDNA-PKcs (T2609) foci in rat and human lymphocytes significantly higher than those of nonirradiated control (trat =21.05,25.80,th =11.07,29.52,P ＜ 0.05),and the frequencies of co-localization of pATM (S1981) or pDNA-PKcs (T2609) foci with γ-H2AX foci also markedly increased by 26％-32％ in irradiated lymphocytes of rat and human (trat =5.34,9.14,thuman =18.32,51.28,P ＜0.05).Moreover,γ-H2AX foci incidence in rat lymphocytes in vitro was consistent with that induced by total body irradiation of rat.The number of γ-H2AX foci in irradiated rat lymphocytes increased with irradiation dose in a linear dose-dependent manner,its slope was similar to that of irradiated human lymphocytes reported by other laboratory.Conclusions Rat is a useful animal model to evaluate radiation biodosimetry with γ-H2AX foci in lymphocytes.The co-activation of ATM and DNA-PK plays an important role in DSB repair in the irradiated lymphocytes of rat and human.

Objective To investigate the effects of glycogen synthase kinase-3β (GSK-3β) and β-catenin signaling on the human renal proximal tubular epithelial HK-2 cell injury induced by depleted uranium(DU),and provide a new enlightenment for the development of DU antidotes.Methods H K-2 cells were exposed to different concentrations of DU for 3-24 h,then the protein expressions of kidney injury molecule 1 (KIM-1),neutrophil gelatinase-associated lipocalin (NGAL) and nuclear β-catenin were detected by immunofluorescence staining.The protein expressions of p-GSK-3 β(S9),GSK-3β and cmyc were detected by Western blot assay.HK-2 cells were transiently transfected by GSK-3β (KD) plasmid or treated by TDZD-8 to inhibit the activity of GSK-3β specifically.Other HK-2 cells were transiently transfected by β-catenin plasmid to overexpress the β-catenin protein.Results The percentages of KIM-1 and NGAL-positive cells increased with DU exposure time and concentrations from 300 and 600 μmol/L,and they were significantly higher than those of the blank control at 6-24 h of DU exposure (KIM-1-positive cells:t =11.06,18.97,30.49,P ＜0.05;t =6.79,16.02,85.45,P ＜ 0.05;NGAL-positive cells:t =11.78,11.37,34.29,P ＜0.05;t =7.34,21.63,36.84,P ＜0.05).In contrast,the ratio of p-GSK-3β (S9) to GSK-3β and percentage of nuclear β-catenin-positive cells were significantly higher than that of the blank control at 3-24 h of DU exposure (p-GSK-3β(S9)/GSK-3β:t =3.95,4.69,5.40,3.34,P ＜ 0.05;nuclear β-catenin-positive cells:t =4.61,6.52,36.64,14.93,P ＜ 0.05) with a maximum response at 9 h of DU exposure accompanied with corresponding increase of protein level of c-myc,a downstream target gene of β-catenin.Transient transfection of HK-2 cells with GSK-3β (KD) plasmid significantly inhibited the activity of GSK-3β (t =8.07,P ＜ 0.05) and reduced the DU-increased percentage of KIM-1-positive cells (t =24.77,P ＜ 0.05).Treatment cells with TDZD-8 inhibited the activity of GSK-3β and enhanced the percentage of nuclear β-catenin-positive cells,and it also significantly reduced the percentage of KIM-1-positive cells in HK-2 cells exposed to DU (t =6.25,6.73,P ＜ 0.05).Moreover,overexpression of β-catenin significantly reduced DU-induced cell injury (t =7.48,P ＜ 0.05).Conclusions GSK-3β/β-catenin signaling plays a key role in regulating the DU-induced cytotoxicity of HK-2 cells.Inhibition of GSK-3β activity and overexpression of β-catenin can protect the HK-2 cells from DU-induced damage.

Objective To investigate the therapeutical effect of triptolide (TP) on subarachnoid hemorrhage (SAH) in rats and its underlying mechanisms.Methods Endovascular perforation technique was used to establish SAH models.TP was used to treat SAH rats by intraperitoneal injection.Rats were randomly divided into control group,SAH 3 d group,SAH 3 d + DMSO group and SAH 3 d + TP group.Pathologic change was observed in rat cortex by HE staining.Cell apoptosis was evaluated by TUNEL assay.Iba-1 considered as microglia marker was assessed by immunohistochemistry.The levels of inflammatory factors including IL-6,IL-1 β and TNF-o were detected by ELISA.Results Compared with control group,pathologic changes,such as cell edema,nuclear pyknosis were more obviously;the number of apoptosis cell,the expression of Iba-1 and the level of inflammatory factors including IL-6,IL-1β and TNF-α were all increased in the cortex of SAH 3 d group,SAH 3 d + DMSO group and SAH 3 d + TP group (P ＜ 0.05).There were no significant differences in pathologic changes,the number of apoptosis cells,the expression of Iba-1 and the levels of inflammatory cytokines in the brain cortex between SAH 3 d group and SAH 3 d + DMSO group (P ＞ 0.05).Compared with SAH 3 d group and SAH 3 d + DMSO group,pathologic changes were alleviated,and the number of apoptosis cells,the expression of Iba-1 and the levels of inflammatory cytokines including IL-6,IL-1β and TNF-α were all decreased in the brain cortex in SAH 3 d + TP group.Conclusion TP could alleviate the pathologic changes,reduce the cell apoptosis and inhibit the microglia activation in rat brain cortex after SAH,and the neuroprotective effect of TP might be associated with the decreased levels of inflammatory cytokines.

Objective:To investigate functional outcomes and condition-specific quality-of-life (CSQoL) after intersphincteric resection (ISR) in patients with low rectal cancer using traditional and exploratory questionnaires.Methods:A prospective observational study was conducted in the Characteristic Medical Center of the People′s Liberation Army Rocket Force. Patients with low rectal cancer who underwent ISR with ileostomy reversal from May 2020 to April 2023 were enrolled. An electronic self-assessment survey was sent to enrolled patients at 3 to 6, 12, and 24 to 36 months after reversal, and differences in functional and CSQoL results between the 3 groups were analyzed with generalized estimation equations. Functional outcomes were determined by the Wexner incontinence score (WIS) and the low anterior resection syndrome (LARS) score. In line with the five frequency responses ranging from never (score 0) to always (score 4) defined by the WIS, an exploratory survey was used to measure the severity of 16 LARS-specific variables confirmed by the latest international Delphi consensus. Furthermore, CSQoL was evaluated using the fecal incontinence quality-of-life scale (FIQL) and the visual analog scale (VAS).Results:A total of 90 patients were enrolled in the study. There were 64 males and 26 females, aged (58.6±10.4) years (range: 28 to 79 years). The median distance from the distal tumor margin to the anal verge( M(IQR)) was 3.0 (1.5) cm (range: 1.0 to 5.0 cm). There were 55 patients who completed the questionnaires at 3 to 6 months, 59 patients at 12 months, and 40 patients at 24 to 36 months of follow-up, respectively. The summary score of FIQL and VAS improved significantly after reversal (2.33±0.69 vs. 2.40±0.66 vs. 2.79±0.76, χ2=11.703, P=0.003; 5.31±1.65 vs. 5.61±1.90 vs. 6.58±1.92, χ2=12.781, P=0.002), but the differences in the WIS and LARS score did not reach statistical significance (both P>0.05). The survey responses for the LARS-specific variables indicated that “emptying difficulties” and “dissatisfaction with the bowels” were the most frequent symptom and consequence after ISR, respectively. The exploratory severity score for LARS improved significantly among the 3 time periods(34 (14) vs. 31 (13) vs. 23 (17), χ2=13.952, P=0.001). Furthermore, the FIQL summary score was strongly correlated with the LARS severity score ( r s=-0.72, P<0.01). Conclusions:Although a high prevalence of LARS may persist for years, patients reported an improvement in CSQoL and functional outcomes after ISR. The highest priorities recommended by the international consensus might provide better assessments the severity of LARS.

Objective? To investigate the hope level of elderly patients undergoing total knee arthroplasty (THA) and analyze its influencing factors, so as to provide evidence for improving the hope level and quality of life of patients after THA. Methods? A cluster random sampling method was used to select 308 patients with bilateral THA for the first time who were admitted to two ClassⅢ Grade A general hospitals in Harbin from January 2017 to July 2018. Questionnaire surveys were conducted using Herth Hope Scale, the Second Edition of Beck Depression Scale and Social Support Scale. Results? The total score of hope level in elderly THA patients was (29.96±8.72). Among them, 76.62% (236/308) had moderate to high level of hope and the total score of depression was (19.20±11.75) which was at a moderate level. There were significant differences in the hope level of patients with different gender, place of residence, educational level, marital status and family per capita monthly income (P＜ 0.05). The results of multiple stepwise regression analysis showed that age, sex, family income per capita, depression, negative coping style, subjective support and objective support were the influencing factors of elderly THA patients' hope level (P ＜ 0.05). Conclusions? The THA patients' hope are at a medium level. Medical staff should pay attention to the relevant factors affecting the level of hope, adopt targeted nursing intervention measures, give psychological guidance to patients, provide social support, and further improve the level of hope of the THA patients.

Objective To explore the difference in gut microbiota composition between patients with obstructive sleep apnea(OSA)and healthy individuals and the role of gut microbiota in the pathogenesis of OSA.Methods Thirty-nine patients with OSA admitted to our hospital between May and December,2022 and 20 healthy individuals were enrolled in this study.Stool samples were collected from all the participants for analysis of microbiome composition using 16S rRNA high-throughput sequencing analysis.The alpha diversity,beta diversity,and species difference were determined between the two groups and marker species analysis and metabolic pathway function prediction analysis were performed.Results The species diversity(Shannon and Simpson)indexes,richness(observed species)and evenness(Pielou)of gut microbiota were significantly lower in OSA patients than in the healthy individuals(P<0.05).The OSA patients had also a significantly lowered community diversity(P<0.05)with different gut microbial communities from those of the healthy individuals shown by increased relative abundance of potentially pathogenic bacteria such as Pseudomonas and Monocytogenes(P<0.05).LEfSe analysis showed that the abundance of 23 species of gut microbiota differed significantly between the two groups and the OSA patients had significant increases in the abundance of Pseudomonas,Meganomonas,and Fusobacterium(P<0.05).The differential marker flora affected host homeostasis.Random Forest and ROC curve analyses confirmed that Pseudomonas could be used as important biomarkers for a differential diagnosis.Metabolic pathway function prediction analysis showed that biosynthesis function had the greatest contribution to maintaining gut microbiota homeostasis,and Pseudomonas affected the occurrence and progression of OSA by participating in aromatic bioamine degradation and ketogluconic acid metabolic pathway.Conclusion OSA patients have obvious gut microbiota disturbances,and Pseudomonas may affect the development of OSA by participating in substance metabolism to serve as the potential target gut bacteria for OSA treatment.

Objective:To investigate functional outcomes and condition-specific quality-of-life (CSQoL) after intersphincteric resection (ISR) in patients with low rectal cancer using traditional and exploratory questionnaires.Methods:A prospective observational study was conducted in the Characteristic Medical Center of the People′s Liberation Army Rocket Force. Patients with low rectal cancer who underwent ISR with ileostomy reversal from May 2020 to April 2023 were enrolled. An electronic self-assessment survey was sent to enrolled patients at 3 to 6, 12, and 24 to 36 months after reversal, and differences in functional and CSQoL results between the 3 groups were analyzed with generalized estimation equations. Functional outcomes were determined by the Wexner incontinence score (WIS) and the low anterior resection syndrome (LARS) score. In line with the five frequency responses ranging from never (score 0) to always (score 4) defined by the WIS, an exploratory survey was used to measure the severity of 16 LARS-specific variables confirmed by the latest international Delphi consensus. Furthermore, CSQoL was evaluated using the fecal incontinence quality-of-life scale (FIQL) and the visual analog scale (VAS).Results:A total of 90 patients were enrolled in the study. There were 64 males and 26 females, aged (58.6±10.4) years (range: 28 to 79 years). The median distance from the distal tumor margin to the anal verge( M(IQR)) was 3.0 (1.5) cm (range: 1.0 to 5.0 cm). There were 55 patients who completed the questionnaires at 3 to 6 months, 59 patients at 12 months, and 40 patients at 24 to 36 months of follow-up, respectively. The summary score of FIQL and VAS improved significantly after reversal (2.33±0.69 vs. 2.40±0.66 vs. 2.79±0.76, χ2=11.703, P=0.003; 5.31±1.65 vs. 5.61±1.90 vs. 6.58±1.92, χ2=12.781, P=0.002), but the differences in the WIS and LARS score did not reach statistical significance (both P>0.05). The survey responses for the LARS-specific variables indicated that “emptying difficulties” and “dissatisfaction with the bowels” were the most frequent symptom and consequence after ISR, respectively. The exploratory severity score for LARS improved significantly among the 3 time periods(34 (14) vs. 31 (13) vs. 23 (17), χ2=13.952, P=0.001). Furthermore, the FIQL summary score was strongly correlated with the LARS severity score ( r s=-0.72, P<0.01). Conclusions:Although a high prevalence of LARS may persist for years, patients reported an improvement in CSQoL and functional outcomes after ISR. The highest priorities recommended by the international consensus might provide better assessments the severity of LARS.

Objective To explore the difference in gut microbiota composition between patients with obstructive sleep apnea(OSA)and healthy individuals and the role of gut microbiota in the pathogenesis of OSA.Methods Thirty-nine patients with OSA admitted to our hospital between May and December,2022 and 20 healthy individuals were enrolled in this study.Stool samples were collected from all the participants for analysis of microbiome composition using 16S rRNA high-throughput sequencing analysis.The alpha diversity,beta diversity,and species difference were determined between the two groups and marker species analysis and metabolic pathway function prediction analysis were performed.Results The species diversity(Shannon and Simpson)indexes,richness(observed species)and evenness(Pielou)of gut microbiota were significantly lower in OSA patients than in the healthy individuals(P<0.05).The OSA patients had also a significantly lowered community diversity(P<0.05)with different gut microbial communities from those of the healthy individuals shown by increased relative abundance of potentially pathogenic bacteria such as Pseudomonas and Monocytogenes(P<0.05).LEfSe analysis showed that the abundance of 23 species of gut microbiota differed significantly between the two groups and the OSA patients had significant increases in the abundance of Pseudomonas,Meganomonas,and Fusobacterium(P<0.05).The differential marker flora affected host homeostasis.Random Forest and ROC curve analyses confirmed that Pseudomonas could be used as important biomarkers for a differential diagnosis.Metabolic pathway function prediction analysis showed that biosynthesis function had the greatest contribution to maintaining gut microbiota homeostasis,and Pseudomonas affected the occurrence and progression of OSA by participating in aromatic bioamine degradation and ketogluconic acid metabolic pathway.Conclusion OSA patients have obvious gut microbiota disturbances,and Pseudomonas may affect the development of OSA by participating in substance metabolism to serve as the potential target gut bacteria for OSA treatment.

【Objective】 To investigate the expression of CD36 antigen in Suzhou area, analyze the type of antigen deficiency and gene mutation, so as to provide references for the establishment of CD36 negative donor registry in Suzhou. 【Methods】 Anticoagulant whole blood samples (805 cases) were randomly collected from healthy blood donors in Suzhou Blood Center. The expression of CD36 antigen on platelet and monocyte was analyzed by flow cytometry to determine the type of CD36 deficiency. The gene mutation type of platelet CD36 antigen-deficient was performed by genomic DNA sequencing. 【Results】 The CD36 deficiency frequency on platelet was 2.48% (20/805), among which TypeⅠ(lacking CD36 expression both on platelet and monocyte) and TypeⅡ(lacking CD36 expression on platelet only) CD36 deficiency accounted for 10% (2/20) and 90% (18/20), respectively. CD36 gene mutations were found in 10 samples, including 3 cases of 329_330 d^elAC, 1 case of 1228_1239 d^elATTGTGCCTATT and 2 cases of 1163 A>T; 1 case of 329_330 d^elAC+ 1172_1183 d^elTATTGGTCAAGC and 287 G>C+ 329_330 d^elAC heterozygous mutation. In addition, 1 case of 745 A>G and 1 case of 806 C>T mutations were novel, and not yet reported. 【Conclusion】 Results showed that the frequency of CD36 antigen deficiency in Suzhou were similar to that reported in southern China, but the mutation sites were slightly different. The establishment of CD36 negative platelet registry could provide negative platelets for patients with transfusion reactions caused by anti-CD36 antibody and improve the effect of clinical platelet transfusion.