Abstract: Objective To evaluate the key quality control and protective performance test of Halcyon medical linear accelerator. Methods WS 674-2020Specification for Testing of Quality Control in Medical Linear Accelerator（ According to the hereinafter WS 674-2020） ， referred to and the manufacturer´s manual the performance of the first Halcyon medical linear accelerator in Results ， ， Hunan Province was tested. The results showed that all ten indicators of the accelerator including dose deviation ， ， （ ， ， ， - repeatability linearity daily stability and symmetry the results were 0.10% 0.03% 0.04% 0.50% and 100.50% 100.80% ）， - - respectively met the requirements of WS 674 2020. The results of manufacturer quality control indicators such as dose rate ， ， stability in beam gantry rotation isocenter and mechanical position accuracy megavolt image parameters and cone beam computer tomography image parameters met the requirements of the manufacturer´s regulations. Due to the special structure and ， - ： function of the accelerator it is difficult to detect the parameter required by WS 674 2020 as below the radiation leakage - ， ， ， ， outside the M zone the uniformity the indicators related to the light field the offset of the radiation beam axis the zero scale Conclusion - position of the rotating motion scale and others. It is difficult to carry out complete testing according to WS 6742020 for Halcyon medical linear accelerator and it is urgent for the state to issue relevant testing standards to standardize and strengthen the quality control testing of various accelerators.

Background and purpose: L-asparaginase (L-Asp) is an important drug in the treatment of childhood lymphoid neoplasms at present, but a lot of adverse reactions of L-Asp were observed. Pegasparaginase (PEG-Asp) is available in China in recent years. This study aimed to explore efifcacy and side-effect of PEG-Asp as ifrst-line treatment in childhood acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LBL). Methods:A total number of 211 ALL or LBL patients were treated with CCLG 2008 or BFM-90 protocol with PEG-Asp or L-Asp between Apr. 2008 and Mar. 2013;42 patients, among whom, were 35 ALL patients and 7 LBL patients, were treated with PEG-Asp as ifrst-line treatment;169 patients were treated with L-Asp as ifrst-line treatment (including 53 patients treated with L-Asp during induction protocol; with PEG-Asp during consolidate protocol). The clinical outcome and adverse reaction of PEG-Asp with L-Asp were observe and compared. Results: There were 35 ALL patients in PEG-Asp ifrst-line treatment group and the complete remission rate after 1 course of PEG-Asp was 97.1%,however, which was 83.3%of high risk ALL patients. The complete remission rate of 7 LBL patients of PEG-Asp ifrst-line treatment group was 57.1%. There was no signiifcant difference between 2 groups (P>0.05). Thirty-four patients relapsed including 5 patients of PEG-Asp ifrst-line treatment group, 16 patients of L-Asp ifrst-line treatment group and 13 patients treated with L-Asp during induction protocol and with PEG-Asp during consolidate protocol. Thirty-one patients died including 3, 18, 10 patients in 3 groups respectively. Twenty-two patients died of relapse, 4 died without remission, 5 died of complications. There was also no signiifcant difference between 2 groups (P>0.05). The incidence rates of adverse reactions were 47.6% and 63.3% respectively. Anaphylaxis, liver functions abnormalities, blood coagulation abnormalities, gastrointestinal reaction, hyperglycemia and pancreatitis were common in our patients. The incidence rate of anaphylaxis in PEG-Asp as ifrst-line treatment group was lower than other groups (P=0.03). But there was no signiifcant difference been observed in the incidence of other adverse reaction. Conclusion: The short-term efifcacy of PEG-Asp as the ifrst-line treatment in childhood leukemia and lymphoma was satisfactory and the incidence rate of anaphylaxis was lower. However, we will still pay much attention to adverse reaction monitoring of PEG-Asp.

Objective To study the mRNA expression of HS1-associated protein X-1(Hax-1),an an- ti-apoptosis genc,in the peripheral blood mononuclear cells(PBMC)of patients with systemic lupus erythe- matosus(SLE),and further investigate the roles and significance of Hax-1 in the pathogenesis of SLE.Meth- ods Generation of longer cDNA fragments from serial analysis of gene expression(SAGE)tags for gene identi- fication(GLGI)was applied to identify the gene Hax-1 according to the Long SAGE tag.Then reverse tran- scription-polymerase chain reaction(RT-PCR)technique was used to semiquantitatively analyze mRNA ex- pressions of Hax-1 in PBMC from 34 active SLE patients and 25 healthy subjects.Results Compared with healthy controls,there was significant difference between SLE patients in the active stage and the normal controls(Z=-4.556,P＜0.01).The average level of mRNA expression in active SLE group was higher than that in healthy controls.Significant difference was found between the group with mild SLE and either the moderate or the severe one(P＜0.01).Conclusion The mRNA expression level of Hax-1 in active SLE group increase markedly,and to some extent,it is related to the activity of SLE.This provides a valuable basis for the further study on the role of apoptosis in SLE.

OBJECTIVETo explore clinical effect of vacuum sealing drainage (VSD) combined with discontinuous windowing technique for repairing large area exposed wounds of Achilles tendon.

METHODSFrom July 2009 to May 2014, 11 patients with large exposed wounds of Achilles tendon were treated, including 5 males and 6 females with an average age of 43 years old (aged from 7 to 65 years old). Among them, 4 cases were skin necrosis caused by heavy objects abrasion and contusion; 3 cases were caused by distal tibiofibula fractures; 3 cases were caused by bicycle-spoke injuries; 1 case was caused by diabetes. Areas of exposed Achilles tendon were from 6 cmx3 cm to 14 cmx5 cm without tendon rupture or bone exposed. After debridement, discontinuous fenestration on Achilles tendon was made by knife blade parallel with longitudinal axis of Achilles tendon, combined with Vacuum Sealing Drainage (VSD) treatment.

RESULTSAfter drainage treatment with one VSD cycle (5 to 7 days), abundant fresh granulation tissues were growing on all wounds and survived well after the second phase dermatoplasty. All patients were followed up for 12 to 24 months, the color of skin flap was good, the texture was soft without burst. At 3 to 4 months after operation, subcutaneous fat was appeared under the flap, the skin was sliding, movement of ankle joints was good. No delayed Achilles tendon rupture were occurred.

CONCLUSIONVacuum sealing drainage (VSD) combined with discontinuous fenestration is a simple, safe and effective method for repairing large area exposed wounds of Achilles tendon,which could minimize the secondary damage caused by wounds of skin flap grafting.

Achilles Tendon ; injuries ; surgery ; Adolescent ; Adult ; Aged ; Child ; Drainage ; methods ; Female ; Humans ; Male ; Middle Aged ; Vacuum

Objective To investigate the efficacy and prognostic risk factors of ALL-R-2003 protocol in the treatment of relapsed childhood relapsed acute lymphoblastic leukemia (ALL) in single center. Methods A retrospective study of clinical data of 51 children with relapsed ALL from January 2004 to December 2014 was performed by using SPSS version 19.0 statistical software for statistical analysis. Results The median age at initial diagnosis of 51 patients was 5.5 years (range, 0.8-13.4 years). The median time from initial diagnosis to relapse was 25 months (range, 3-68 months) and follow-up time was 39 months (range, 3-116 months). The relapse rate in the standard-risk, intermediate-risk and the high-risk groups were 27.5 % (14/51), 29.4 %(15/51) and 43.1 % (22/51), respectively. The probability of 3-year overall survival (pOS) after relapse was (18.8±5.9)%and the probability of event free survival (pEFS) was (16.2±5.8)%. The 3-year pOS in very early relapse, early relapse and late relapse were 0, (11.7 ±7.7) % and (51.7 ±14.8) %, respectively (P= 0.000). There was no statistical difference in survival rate of different immunophenotype groups and sites of relapse (P> 0.05). The 3-year pOS of group S1, S2, S3, S4 were (50.0±35.4) %, (39.9±1.3) %, (10.0±9.5) % and 0, respectively (P=0.000). The 3-year pOS of bcr-abl and MLL gene positive groups were (25.0±21.7) %and 0, respectively, with no statistically significance compared with the negtive group [(24.1±12.0)%] (P>0.05). The 3-year pOS rates of children with bone marrow transplantation and without transplantation were (40.0 ±15.5) %and (13.0 ±5.9) % respectively (P= 0.038). Conclusions The children who in high risk group at initial diagnose are easily to meet earlier relapse and poorer prognosis. The survival period after relapse of bcr-abl or MLL gene positive cases is very short. Bone marrow transplantation can improve survival rate. Risk group at initial diagnose, relapse time and transplantation are the main factors influencing prognosis, and the relapse time and transplantation are the independent prognostic factors for relapsed childhood ALL.

Objective To explore the safety of the mobilization of peripheral blood stem cells(PBSC)by granulocyte colony-stimulating factor(G-CSF)in elderly donors.Methods 28 peripheral arteriosclerotic occlusive disease(PAOD)elderly patients(aged≥60 years),and 29 healthy sibling young/adult donors(aged＜60 years)for peripheral allogenic stem cell transplantation were included.Blood samples were collected immediately before starting G-CSF and prior to PBSC collection to analyze the following parameters:the WBC counts,fibrinogen(FIB),D-dimer (D-D),thrombin antithrombin complex(TAT),antithrombin(AT)and yon Willebrand factor antigen(vWF:Ag). Results It had a very significant increase in D-D and vWF:Ag and a very significant decrease of AT(P＜0.01),af- ter mobilization by G-CSF,and a increase in FIB and TAT were also observed(P＜0.05,P＜0.01)in elderly group.In the young/aduh group,the increase in FIB was significant(P＜0.05).The elevating extent of D-D and TAT after G-CSF administration was significantly higher in elderly group than that in young/adult group(P＜0.05).Compared to young/adult group,there was a significant increase in thrombotic events and cerebrovascular ac- cident(P＜0.05).Conclusion In PBCS donorsreceiving G-CSF it reveals activation of both coagulation and en- dothelial cells and inhibition of anticoagulant system that can favor the developing of thrombotic events,which is more remarkable in elderly donors.Therefore a careful monitoring for coagulation system should be considered in those elderly cases.

OBJECTIVECeramic brackets debonding by Nd:YAG laser is based on the thermal effect of laser, which may cause injury of the pulp tissue. In this study, the histological changes of pulp tissue that subjected to Nd: YAG laser irradiation with different power and time were observed.

METHODS20 New Zealand rabbits were included in this study. Ceramic brackets were bonded to the 4 incisors as routine. The ceramic brackets of left upper teeth that debonded mechanically were used as control group, while the brackets of right upper, left lower and right lower incisors were debonded by laser with 3 W 3 s (group A), 2 W 5 s (group B) and 5 W 2 s (group C) energies, respectively. The teeth were pulled out at 5 minutes, 1 day, 3 days, 1 week and 1 month after the debonding operations. Slides prepared from the pulp tissues of the debonded teeth were used to evaluate the injury of laser.

RESULTSIn comparison with the control group, pulp tissue of teeth that exposed to laser with different energy for 5 minutes showed mild capillary dilation. One day later, group A, B and C showed moderate capillary dilation, and group C also showed moderate infiltration. At 3 days, inflammation was disappeared in group B, whereas capillary dilation was found in group A. Hemorrhage and inflammation cells infiltration were found in group C. At 1 week, alleviation of capillary dilation was found in group A but not in group C. One month later, inflammation disappeared in group A, while pulp tissue in group C showed mild edema and capillary dilation.

CONCLUSIONNd:YAG laser of high energy may cause injury of the pulp tissue during debonding. Laser energy of 3 W 3 s could effectively debond ceramic brackets without irreversible pulp injury.

Animals ; Ceramics ; Dental Debonding ; Dental Pulp ; Lasers ; Lasers, Solid-State ; Orthodontic Brackets ; Rabbits

Objective: To facilitate the functional analysis of chromosomal genes and their products, the recombineering technique to epitope tagging of chromosomal genes of Y. pestis was adapted. Methods: The epitope tag was generated by primer annealing and then fused with resistance gene by fusion PCR. The epitope-resistance cassette was inserted into pBluecript, resulted in the template plasmid, pBS-MH. The tagging cassette for rpoS was obtained by PCR amplification from pBS-MH with primers containing homology specific to the target gene. PCR products were transformed into recombination competent cells and recombinants were selected. PCR and DNA sequencing were used to confirm the correct tagging event. The expression of the tagged protein was detected with Western blot by using monoclonal antibody to the epitope. Results: The template plasmid containing fusion of epitope and resistance gene was successfully constructed. The sigma factor gene, rpoS, was tagged with a myc-his tag at the COOH terminus. Expression of the tagged rpoS was successfully detected indirectly by the antibody against His tag. Conclusion: The chromosomal gene tagging by recombineering technique represents a powerful tool in the functional study of bacterial genes and their products.

Objective:To investigate the short term outcomes and postoperative respiratory complications of patients with chronic thromboembolic pulmonary hypertension(CTEPH) treated by pulmonary endarterectomy(PEA).Methods:45 consecutive CTEPH patients underwent PEA between December 2017 and January 2020 in our institution were enrolled, including 25 females and 20 males. The mean age of operation was 51.2(25-70) years old. 24(53.5%) patients were in New York Heart Association(NYHA) functional class Ⅲ-Ⅳ. The mean PVR before operation was 923(461-2 711) dyn·s·cm -5. All patients’ data were entered in a prospective database, divieded into patients with respiratory complications group(WRC)and without respiratory complications group(WORC). To assess risk factors for postoperative respiratory complications and its effect on short term outcomes. Results:There was a significant reduction in mPAP(from 37 mmHg to 20 mmHg) and PVR(from 923 dyn·s·cm -5 to 293 dyn·s·cm -5) in the entire group. The in-hospital mortality rate was 4.4%(2 cases), died due to postoperative cardiogenic circulatory failure, even with VA-ECMO treatment and mediastinal infection, respectively. Postoperative respiratory complications occurred in 32 patients(71.1%). The most common complications were reperfusion pulmonary edema 44.4%(20 cases) and residual pulmonary hypertension 11.1%(5 cases). The WRC group showed a tendency to have longer periods of mechanical ventilation, longer ICU stays and more ICU costs. Independent predictors of postoperative respiratory complications were time from symptom onset to PEA>36 months( OR=12.2, 95% CI: 2.1-70.7, P=0.005)and six-minute walking distance<300 m( OR=12.6, 95% CI: 1.1-138.0, P=0.0038). Conclusion:Pulmonary endarterectomy is an effective and safe treatment for CTEPH. Postoperative respiratory complications were mainly determined by symptom onset time and pre-operative status. Patients with CTEPH should consider PEA surgery early.

OBJECTIVETo identify the interaction partners of a new splicing product of LMO2 gene (LMO2-C), and study its function in K562 cells.

METHODSMaltose binding protein (MBP) pull down and mammalian two-hybrid assay (MTHA) were used to identify the interaction partners of LMO2-C in K562 cells. Semiquantitative RT-PCR was used to detect the expression of hematopoietic specific gene glycoprotein (GPA) in K562 cells.

RESULTSMBP-LMO2-C fusion protein was expressed and purified in soluble form successfully. Endogenous GATA1 and LDB1 proteins were confirmed to bind to LMO2-C by MBP pull down analysis. The MTHA also showed that LMO2-C had comparable binding affinities to LDB1 with LMO2-L, and over expression of LMO2-C prevented LMO2-L from binding to LDB1, the inhibition rate being (81.13 +/- 0.68)%. RT-PCR results showed that the expression level of GPA was reduced [(51.00 +/- 1.58)%] in K562 cells while LMO2-C overexpressed.

CONCLUSIONLMO2-C can bind endogenous GATA1 and LDB1 protein in K562 cells and down regulates the expression of GPA.

Adaptor Proteins, Signal Transducing ; DNA-Binding Proteins ; genetics ; metabolism ; GATA1 Transcription Factor ; metabolism ; Humans ; K562 Cells ; LIM Domain Proteins ; Maltose-Binding Proteins ; Metalloproteins ; genetics ; metabolism ; Periplasmic Binding Proteins ; Proto-Oncogene Proteins ; RNA Splicing ; Transcription Factors ; metabolism ; Two-Hybrid System Techniques