Objective To evaluate the peripheral dose (PD) from megavoltage cone-beam CT (MVCBCT) imaging for head-and-neck region image-guided radiation therapy,to determine the correlation of PD with monitor unit (MU),and to investigate the impact of imaging field size on the PD.Methods Measurements of PD from MVCBCT were made with a 0.65 cm3 ionization chamber placed in a specially designed phantom at various depths and distances from the field edges.The PD at reference point inside the phantom was measured with the same ionization chamber to investigate the linearity between MU used for MVCBCT and the PD.The homogeneity of PD in the axial plane of the phantom were measured.Results PD from MVCBCT increased with increasing number of MU used for imaging and with increasing the field size.The measured PD in the phantom decreased exponentially as distance from the field edges increased.PD also decreased as the depth from the phantom surface increased.There was a strong linear relationship between PD and MUs used for MVCBCT.The PD was heterogeneous,with higher dose at the anterior than the posterior.Conclusions The PD from MVCBCT depend much on the MVCBCT delivery MU and the scan field size.In clinic,using the smallest number of MU allowable and reducing MVCBCT scanning field size without compromising acquired image quality is an effective method of reducing the PD.

Objective To compare the whole-body equivalent doses from volumetric modulated arc therapy (VMAT) and static intensity-modulated radiotherapy (IMRT) for patients with cervical cancer.Methods Nine patients with cervical cancer admitted to our hospital in 2014 were included in this study.Both VMAT and IMRT were planned for each patient.Each patient's personal dose equivalent (Hp (10)) was measured using thermoluminescent dosimeters placed at the xiphoid process and glabella during IMRT and VMAT.The whole-body equivalent doses were estimated based on the results measured at the xiphoid process and compared between the VMAT and IMRT techniques.The paired t test was used for difference analysis.Results The Hp (10) values measured at the xiphoid process and glabella of every patient were lower for VMAT than for IMRT.At a prescribed dose of 50 Gy,if the mean Hp (10) values measured at the xiphoid process were considered to represent the whole-body equivalent doses,the whole-body equivalent doses for VMAT and IMRT were 364 mSv and 538 mSv,respectively.Conclusions VMAT results in a lower whole-body equivalent dose to patients compared with IMRT.The decreased whole-body equivalent dose delivered by VMAT may reduce the likelihood of a radiation-induced secondary malignancy.

OBJECTIVETo prepare stable chicken red blood cells for the calibration of flow cytometry.

METHODSThe traditional isolation method of chicken red blood cells was modified by incorporating gelatin technique, Ca2+-free HBSS treatment and low-speed centrifugation. The effect of fluorescence staining of the cells was improved by the addition of TritonX-100 to enhance the membrane permeability and Rnase enzymes to disintegrate RNA tiles. The modified method was compared with the traditional method for viability of the freshly isolated cells and the DNA content coefficient of variation (CV) of the fixed cells.

RESULTSChicken red blood cells obtained by the modified method showed a significantly higher viability than those obtained by the traditional method [(98.5∓3.5)% vs (93.5∓2.7)%, P<0.05]. After glutaraldehyde fixation, the isolated cells with the modified method were stable during the 90-day preservation with a significantly lower CV than the cells obtained by the traditional method [(6.0∓0.3)% to 6.2∓0.4% vs (8.6∓0.5)% to (13.1∓1.4)%, P<0.01].

CONCLUSIONThe chicken red blood cells isolated using the modified method can be applicable for calibration of flow cytometry.

Animals ; Calibration ; Chickens ; Erythrocytes ; cytology ; Flow Cytometry ; instrumentation ; methods

There is high demand for a sensitive method for miRNA detection in clinical diagnosis. In this work, we developed a method for miRNA detection based on the surface plasmon-enhanced energy transfer ( SPEET ) between gold nanoparticles ( AuNPs ) and silver nanoclusters ( AgNCs ) , coupled with DNA polymerase and nicking enzyme-assisted isothermal amplification for target recycling. Two DNA probes ( Probe a and Probe b) were assembled onto the surface of AuNPs to form Probe b-Probe a-AuNP conjugates. Probe a consisted three domains:the complementary sequence of miRNA, the specific site of the nicking enzyme, and the self-assembly sequence for AgNCs. The 3′ end of Probe a was modified with thiol as a binding site for AuNPs. The SPEET of AgNCs and AuNPs was inhibited when miRNA was added to produce the dumbbell shaped template by polymerase. The template could promote synthesis of AgNCs, resulting in replacement and subsequently recycling of the target molecule for signal amplification. In comparison with the traditional method of miRNA detection with commercial RT-PCR kits, this method avoided the process of reverse transcription and was easy to perform. In addition, this method with a detection limit of 2. 5×10-11 mol/L was cost-effective, label-free, and highly selective for detecting miRNA, and could be applied to the analysis of miRNA in biological samples.

Objective To explore the effect of KRT6A on radiation resistance in non-small cell lung cancer A549 cells and its mecha-nism of action.Methods The radiation-resistant A549(A549-RR)cells were induced and established.The successful construction of the cells were performed using the Cell Counting Kit 8(CCK-8)method,plate clone-formation experiments,and flow cytometry.Western blot-ting was used to detect the expression of KRT6A in A549 and A549-RR cells.A549-RR cells were divided into the sh-NC,sh-KRT6A,sh-KRT6A+ov-NC,and sh-KRT6A+ov-β-catenin groups.The expression of KRT6A;β-catenin;and epithelial-mesenchymal transition(EMT)-related proteins E-cadherin,N-cadherin,vimentin,Snail,and Slug were detected by Western blotting.The CCK-8 assay,plate clone-formation experiments,and flow cytometry were used to determine the radiation resistance of the cells.Results A549-RR cells were successfully cultured.and KRT6A expression was upregulated in A549-RR cells compared to A549 cells.Knocking down KRT6A reduced the proliferative activity and clonogenic ability of A549-RR cells;increased the apoptosis rate;upregulated the expression of E-cadherin protein;and downregulated N-cadherin,vimentin,Snail,Slug,andβ-catenin protein expression.Overexpression ofβ-catenin reversed the inhibitory effect of KRT6A knockdown on EMT and radiation resistance in A549-RR cells.Conclusion KRT6A is upregu-lated in A549-RR cells,and knocking down KRT6A reduces the radiation resistance of A549-RR cells,which may be related to the induc-tion of EMT by activation of the Wnt/βcatenin signaling pathway.

OBJECTIVETo comprehend the anatomic characteristics and correlations between the accessory nerve and the phrenic nerve in the adult corpses.

METHODSThe bilateral accessory nerves, phrenic nerves, and their branches of 20 adult corpses (38 sides) were underwent exposure. The morphologic data of the accessory nerves and the phrenic nerves above clavicle were measured. In addition, the minimal and maximal distances from several points on the accessory nerve to the full length of the phrenic nerve above clavicle were measured. Then, the number of motor nerve fibers on different locations of the nerves utilizing the method of immunohistochemistry were counted and compared.

RESULTThe accessory nerves after sending out the sternocleido-mastoid muscular branches were similar in the morphologic data with the phrenic nerves. Meanwhile, the accessory nerve had a coiled appearance within this geometrical area. The possibly minimal distance between the accessory nerve and phrenic nerve was (3.19 ± 1.23) cm, and the possibly maximal distance between the starting point of accessory nerve and the end of the phrenic nerve above clavicle was (8.71 ± 0.75) cm.

CONCLUSIONSThe accessory nerve and the phrenic nerve are similar in the anatomic evidences and the number of motor nerve fibers. And the length of accessory nerve is sufficiently long to connect with phrenic nerve as needed. It is possible to suture them without strain directly.

Accessory Nerve ; anatomy & histology ; surgery ; Adult ; Female ; Humans ; Male ; Nerve Transfer ; Phrenic Nerve ; anatomy & histology ; surgery

Objective To investigate the impact of adopting different dose grid resolution during volumetric modulated arc therapy (VMAT) planning on COMPASS pass rate.Methods A total of 10 patients with cervical cancer were enrolled.Four types of VMAT plans (plan1,plan2,plan3,plan4) were designed for each patient,with dose grid resolution of 0.2 cm × 0.2 cm × 0.2 cm,0.3 cm × 0.3 cm ×0.3 cm,0.4 cm ×0.4 cm ×0.4 cm and 0.5 cm ×0.5 cm ×0.5 cm,respectively.The plans were exported to Linac and conducted,then measured by COMPASS.The discrepancies were analyzed,which were obtained by comparing reconstructed dose from COMPASS and dose from TPS optimization.Results For tumor volume,the mean value of Dmean and D95 were ＜ 0.5％ and ＜ 1.3％ respectively,and the standard deviation were both ＜ 1.0％.For organs at risk (OAR),the max discrepancies were Dmean of femur with-6.7％,-7.0％,-8.0％,-5.8％,and V35 of rectum with 4.9％,-6.3％,-6.1％,-5.7％ in four types of VMAT plans.The γ (3％,3 am) rate of tumor volume was ＞95％ with standard deviation ＜ 2.5％,with no statistically significant difference among the four types of plans (P ＞0.05).The γ (3％,3 mm) rate of OARs were ＞ 98％ except femur (＞ 95％),and the standard deviations were within 1.9％-6.1％,with no statistical significance (P ＞0.05).The average γ rate of tumor volume and OARs were ＜ 0.4 except femur (＞ 0.4),with no statistically significant difference among four types of VMAT plans (P ＞ 0.05).Conclusions COMPASS pass rate was not influenced by the dose grid resolution between 0.2 ～ 0.5 cm for VMAT plan.

Objective To determine the efficacy ofantiepileptic drugs (AEDs) on prevention of epilepsy after craniocerebral injury. Methods Related articles searched from the databases such as PubMed, Ovid, Springer, VP and CNKI were collected and strictly evaluated; 21 articles were finally selected. Whether pretreatment with AEDs played its role in epilepsy appeared in the early/late stages was discussed with Meta-analysis; the influences of different craniocerebral injury types (resulting from trauma or surgery) on the efficacy of anti-epilepsy prophylaxis, and the mortality rate of the patients performed pretreatment were analyzed with Meta-analysis. Results Pretreatment withAEDs could significantly improve the results (OR=0.66, Z=4.31, P=0.000); pretreatment with AEDs obviously decreased the rate of epilepsy appeared in the early stage (OR=0.48, Z=3.980, P=0.000), but did not statistically decrease the rate of epilepsy appeared in the late stage (OR=1.05, Z=0.310, P=0.760);pretreatment with diphenylhydantoin (OR=0.53) was more effective on epilepsy appeared in the early stage than pretreatment with carbamazepine (OR=0.40). Pretreatment with AEDs was all-effective considering different craniocerebral injury types resulting from trauma (OR=0.48) and surgery (OR=0.69). No significant differences were noted on the mortality rate of patients performed pretreatment and without pretreatment (OR=0.82, Z=0.920, P=0.360). Conclusion The inception rate of epilepsy can be decreased remarkably after anti-epilepsy prophylaxis with AEDs in patients after craniocerebral injury,and diphenylhydantoin has a better effect for epilepsy appeared in the early stage. No reasonable differences between various kinds of AEDs on epilepsy appeared in the late stage are noted. Pretreatment with AEDs enjoys a good result in both post-traumatic brain injury and craniotomy. Pretreatment can not affect the mortality rate of the patients.

Objective To determine the effects of treadmill training on the structure of hippocampal myelin and cognitive function in rats exposed to acute plateau hypoxia.Methods With 30 SPF-grade female SD rats (aged 6-8 weeks,weighing 200-220 g),6 of them were used for observation of myelin structure after injury,and the remaining 24 rats were randomly divided into control group,hypobaric hypoxia group and treadmill training group (n=8).The rats in above experimental groups were placed in a low-pressure oxygen chamber at an altitude of 6000 m for 7 consecutive days,and the rats of the control group were placed in the confined chamber for the same period without hypoxia.Then,the rats of the treadmill training group received a 4-week treadmill training scheme since the day after hypoxia.Finally,all the rats were tested for cognitive function with open field test (OFT)and Morris water maze (MWM).Transmission electron microscopy (TEM) was used to observe the changes of demyelination in the hippocampus. The expression of oligodendrocyte transcription factor 2 (Olig2)and myelin basic protein (MBP )in the hippocampal CA1 and CA3 regions was measured by immunofluorescence staining and Western blotting.Results Behavioral tests showed that the number into the central area,total distance,distance ratio in OFT and the number of platform crossings and distance to the target area in MWM were reduced in the hypobaric hypoxia group than the control group (P<0.05 ),while these indexes were increased in the treadmill training group than in the hypobaric hypoxia group (P<0.05).Immunofluorescence staining indicated that the number of Olig2 positive cells per unit area and the mean fluorescence intensity of MBP in the CA1 and CA3 regions were significantly lessen in the hypobaric hypoxia group than the control group (P<0.05 ),while these indicators were higher in the treadmill training group than the hypobaric hypoxia group (P<0.05 ).Western blotting displayed that the expression levels of Olig2 and MBP in the hippocampus were obviously lower in the hypobaric hypoxia group than the control group (P<0.01 ),while the levels were increased in the treadmill training group than the hypobaric hypoxia group (P<0.01 ).Conclusion Treadmill training promotes the number of the oligodendrocyte spectrum cells in CA1 and CA3 regions,enhances the expression of myelin-related proteins and improves myelin repair in hippocampus of hypobaric hypoxia rats,and thereby ameliorates hypoxia-induced anxiety-like behaviors and memory dysfunction.

Purpose/Significance To analyze the technical situation of patent owners in the field of clinical decision support system(CDSS)in China as a whole,so as to provide references for CDSS related technical research.Method/Process Firstly,the CDSS patent data are analyzed from the aspects of application trend,patent disclosure,technology field distribution,etc.,then the patentees are di-vided into different categories,and their technical concerns are analyzed by word frequency and interword vector.Finally,the technology correlation and patent exclusives are analyzed based on the active patentees.Result/Conclusion The number of CDSS patent disclosure shows an overall increasing trend.This field has not formed a technological monopoly in China.Government departments and research in-stitutions should pay attention to the possible financial risks.