BACKGROUND: Schwann cells are the seed cells of neural repair, and it is a key to harvest a large number of Schwann cells with high purity and activity. OBJECTIVE: To compare the in vitro culture, purification, and morphology of Schwann cells between neonatal and adult rats, and investigate a simple and feasible culture method to harvest high-purity Schwann cells. METHODS: Totally 30 Sprague-Dawley rats, comprising 20 neonatal (1-3 days after birth, neonatal group) and 10 adult (weighing 150-200 g, adult group) rats, were included. Following double-enzyme digestion and two incubations, Schwann cells were isolated and purified by differential attachment. Cell morphology and attaching speed were determined through the use of inverted microscope. Cells were counted and cell purity was calculated. Cell proliferative ability was detected by MTT microcolorimetry. Curves of cell proliferation in each group were depicted to determine proliferative speed. Schwann cells were identified by S-100 immunochemistry.RESULTS AND CONCLUSION: Compared with fibroblasts, neonatal rat Schwann cells exhibited faster, while adult rat Schwann cells showed slower, attaching speed. Both neonatal and adult groups yielded over 96% cell purity. MTT microcolorimetry results revealed that Schwann cells proliferated actively in neonatal and adult groups. Cell proliferative curves show that neonatal rat Schwann cells proliferated faster than adult rat Schwann cells (P < 0.05). S-100 immunochemistry results showed positive results in both groups. All these findings suggest that double-enzyme digestion and two incubations followed by differential attachment is a satisfactory method to harvest considerable Schwann cells with high purity and activity. Neonatal rat Schwann cells show stronger proliferative, attaching capacities than adult rat Schwann cells.

Objective To investigate the effect of berberine on gut microbiota and T helper cell 17 (Th17), regulatory T cell (Treg) cell in sleep deprived rats.Methods SD rats were randomized into control group, model group, low-dose and high-dose group (BBR1 and BBR2, 100 mg/kg and 200 mg/kg, administrated orally).Sleep deprived rat model was established by the small-platforms-over-water method.The number of bacteria in rectum content of rat was detected.The ratio of Th17/Treg was evaluated by flow cytometry.The expression of interleukin 17 (IL-17), RAR-related orphan receptor (ROR) C, and Forkhead Box Protein P3 (Foxp3) mRNA was evaluated.Results The counting of Clostridium perfringens was elevated (P<0.05), the amount of other microbiota decreased (P<0.05), Th17/Treg ratio(P<0.05), IL-17 and RORC expression enhanced (P<0.05), Foxp3 expression decreased (P<0.05) in the gut of model rats.In contrast, treatment with berberine inhibited the proliferation of Clostridium perfringens(P<0.05), and promoted the growth of other microbiota (P<0.05), and dampened Th17/Treg ratio (P<0.05), regressed IL-17 and RORC expression, augmented Foxp3 expression.Conclusions Various doses of berberine can counteract gut microbiota imbalance and Th17/Treg imbalance induced by sleep deprivation.

ObjectiveTo evaluate the effect of labor analgesia and the outcome of maternals and neonatals by applying the vitamin B6- folic acid mixture to combined with spinal-epidural analgesia(CSEA) in nulliparous women at latency.MethodsAll the 112 full-term nulliparous parturients were selected and divided into the treated group and controlled group.Nulliparous women in two groups received CSEA,with which the additional vitamin - folic acid mixture was used only in treatment group.The contrast between the analgesic effect in groups,and alalgesic effect-acting period,fentanyl Apgar score and newborn usage were compared between groups also.ResultsThe analgesic effect-acting period and fentanyl dosage in the treated group were significantly decreased.There was significant difference between the 2 ( P ＜ 0.05 ).ConclusionsIt could be effective applying vitamin B6- folic acid mixture at latency in nulliparous women based on CSEA,which could shorten the lumbar hemp effect-acting period and reduce fentanyl narcotic drugs dosage.

The volume change of tumor during radiotherapy processes indirectly reflects the short-term efficacy and the quality of radiotherapy planning. We analyzed clinical data of radiotherapy using a mathematical model in our study. First, we selected eight esophageal carcinoma patients with only using 3DRT and conventional dose fractionation schemes. And then we observed and measured the change of tumor volume during the radiotherapy. Based on the LQ model, repopulation and re-oxygenation in 4Rs, and the kinetics of doomed tumor disintegration, we established the mathematical model of tumor evolution in radiotherapy. And then we used the model to analyze the clinical trial data about esophageal carcinoma with radiotherapy. It was proved that the results of the model almost coincided with the clinical trial data. According to the analysis results, we could get the related radiobiology parameters to estimate biological effective dose and repopulation of patients. The mathematical model could provide reference for assessment of prognosis and further scheme of treatment.
Algorithms ; Esophageal Neoplasms ; pathology ; radiotherapy ; Humans ; Models, Theoretical ; Radiotherapy Planning, Computer-Assisted ; methods ; Tumor Burden

The schemes of dose fractionation play an important role in tumor radiotherapy. We used mathematical methods to describe the process of tumor cells evolution during radiotherapy, trying to find how the schemes of dose fractionation affect tumor cells. In clinical radiobiology, linear-quadratic (LQ) model is frequently used to describe radiation effects of tumor cells. We integrated LQ model with effect of oxygen, and with the phenomenon of repopulation and reoxygenation in the theory of radiation biology. While we considered the disappearing progress of doomed cells in tumor, we established the mathematical model of tumor evolution in radiotherapy. We simulated some common treatment schedules, and studied the change role of tumor cells during radiotherapy. These results can serve for the optimization of dose fractionation scheme based on tumor radiobiological characteristics.
Cell Growth Processes ; radiation effects ; Dose Fractionation ; Humans ; Models, Theoretical ; Neoplasms ; pathology ; physiopathology ; radiotherapy ; Radiobiology

BACKGROUNDProtein kinase C(PKC) is a potentially important target for can-cer therapeutics due to its potential role in carcinogenesis.Abnormal expression and increasing activity of PKC-α are present in non-small cell lung cancer(NSCLC).PKC inhibitor can show anti-tumor effects through inducing tumor cell apoptosis,enhancing cytotoxic effects and down-regulating expressions of multidrug resistance gene.By observing the effects of PKC inhibitor chelerythrine chloride(CH) on drug-sensitivity to cisplatin of four NSCLC cell lines its mechanism of effect initially is explored.

METHODSNSCLC cell lines(H1299,H460,A549 and cisplatin-resistant A549) were dealed with PKC inhibitor CH respectively.The expressions of PKC-α mRNA and protein in NSCLC cell lines were examined by reverse transcription polymerase chain reaction(RT-PCR) and Western blot.The apoptosis rates of NSCLC cells lines were detected by flow cytometry.The drug-sensitivity to cisplatin of NSCLC cells lines was measured by methabenzthiazuron(MTT) assay.

RESULTSThe expression levels of PKC-α mRNA and protein in cisplatin-resistant A549 cell lines were significantly higher than H1299,H460 and parent A549 cell lines(P < 0.05).The expression levels of PKC-α mRNA and protein in four NSCLC cell lines decreased at different extent.The apoptosis rates of cisplatin-resistant A549 cell lines increased obviously after treating with CH for 4 and 24 hours,but it was not seen in H1299,H460 and parent A549 cell lines.The IC50 value of cisplatin of NSCLC cell lines decreased at different degree after treating with CH and it was more obvious in cisplatin-resistant A549 cell lines(P < 0.05).

CONCLUSIONSHigh expressions of PKC-α mRNA and protein exist in all four NSCLC cell lines.PKC inhibitor CH can enhance the drug-sensitivity of NSCLC cell lines to cisplatin by inhibiting their expression of PKC-α mRNA and protein.When compared with parent A549 cell lines,cisplatin-resistant A549 cell line's drug-sensitivity to cisplatin is increasing more efficiently by PKC inhibitor CH through inhibition of PKC-α protein's expression and elevation of tumor cell apoptosis rates.

Objective:To investigate the effect of different scanning centers on eye lens dose, image quality, and the dose reduction rate when using the organ dose modulation (ODM) technique in head CT.Methods:The porus acusticus externus of the head phantom was considered the scanning isocenter. The ODM was initiated and the spiral scans were performed at the scanning centers with the height of porus acusticus externus and its upper and lower 2, 4, and 6 cm, respectively. The scanning range was from the top of the head to the base of the head. Three thermoluminescent dosimeters (TLD) were placed on the surface of two eyes at each scan and the average measurement value was regarded as the radiation dose to the eye lens. The volume CT dose index (CTDI vol) and dose length product (DLP) were recorded. The scans were repeated with no ODM and the dose reduction rates at each scanning center were calculated. The regions of interest (ROI) in each group of images with ODM were drawn and the noise (SD), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were evaluated. Results:Compared with the isocenter, the maximum change rates of CTDI vol and DLP in each scanning center were 2.46% and 2.43%, respectively. The eye lens dose increased as the scanning centre moving upwars (i.e. the bed dropping) by 39.02% at the position of 6 cm above the isocenter and decreased by 35.91% at the position of 6 cm below the isocenter. With the seven groups of scanning centers, the reduction rates of CTDI vol and DLP caused by ODM were 7.95%-8.61%, 7.91%-8.61% respectively, and the difference in the reduction rate of each dose value was not statistically significant( P>0.05). The reduction rate for eye lens dose ranged from 18.09% to 26.14%, with the highest reduction rate at the position of 4 cm above the isocentre and the second rate at the isocentre (24.73%). The difference in the rate of reduction at each scanning center was statistically significant( t=0.13, P<0.05). As the scanning center moved up, the SD of the eye region decreased and the SNR increased, and the highest CNR at the isocentre was 239.79. The SD and SNR of the brain parenchyma region were 6.85-7.96 and 3.08-4.19 respectively, and the highest CNR at the isocentre was 244.79. Conclusions:When ODM technique is used in head CT, the scan centre has a significant effect on the eye lens dose and image quality. Meanwhile, the reduction rate of the eye lens dose caused by ODM is also affected. Therefore, porus acusticus externus is recommended as the scanning center in head CT.

To explore a method for calculating water equivalent diameter () based on localizer CT images for calculation of the size specific dose estimates (SSDE).GE Revolution CT and LightSpeed VCT were used to scan CT dose index phantoms 16 cm and 32 cm in diameter at the tube voltages of 80, 100 and 120 kV to obtain the axial image and anteroposterior localizer radiograph. According to the definition of CT Hounsfield unit, the axial images were used to calculate the conversion factors that convert the phantom thickness to water equivalent thickness. The gray value of the localizer radiograph and the water equivalent thickness were calibrated with a linear equation, and the parameters of the calibration were used to calculate the water equivalent thickness. The method was verified using 2 CT dose index phantoms and in 22 patients undergoing chest and abdominal CT examination.Comparison of the water equivalent diameter () based on the localizer radiograph and axial image of the 2 phantoms showed that the percentage difference between from the axial images and from the localizer radiograph was below 3%. The trend of variations with location in the two methods was sonsistent. The difference in in intermediate region of interest between the axial image and the localizer radiograph from the 22 patients was below 6.6%. With the mean in the ROI, the maximum percentage difference was 7.5%.Calibration of the gray value of the localizer radiograph and the water equivalent thickness using the axial image and localizer radiograph of CT dose index phantoms allows quick calculation of the SSDE based on the parameters of calibration.
Calibration ; Humans ; Phantoms, Imaging ; Radiation Dosage ; Tomography, X-Ray Computed ; Water

Background::Liver cancer is largely resistant to chemotherapy. This study aimed to identify the effective chemotherapeutics for β-catenin-activated liver cancer which is caused by gain-of-function mutation of catenin beta 1 ( CTNNB1), the most frequently altered proto-oncogene in hepatic neoplasms. Methods::Constitutive β-catenin-activated mouse embryonic fibroblasts (MEFs) were established by deleting exon 3 ( β-cateninΔ(ex3)/+ ), the most common mutation site in CTNNB1 gene. A screening of 12 widely used chemotherapy drugs was conducted for the ones that selectively inhibited β-cateninΔ(ex3)/+ but not for wild-type MEFs. Untargeted metabolomics was carried out to examine the alterations of metabolites in nucleotide synthesis. The efficacy and selectivity of methotrexate (MTX) on β-catenin-activated human liver cancer cells were determined in vitro. Immuno-deficient nude mice subcutaneously inoculated with β-catenin wild-type or mutant liver cancer cells and hepatitis B virus ( HBV); β-cateninlox(ex3)/+ mice were used, respectively, to evaluate the efficacy of MTX in the treatment of β-catenin mutant liver cancer. Results::MTX was identified and validated as a preferential agent against the proliferation and tumor formation of β-catenin-activated cells. Boosted nucleotide synthesis was the major metabolic aberration in β-catenin-active cells, and this alteration was also the target of MTX. Moreover, MTX abrogated hepatocarcinogenesis of HBV; β-cateninlox(ex3)/+ mice, which stimulated concurrent Ctnnb1-activated mutation and HBV infection in liver cancer. Conclusion::MTX is a promising chemotherapeutic agent for β-catenin hyperactive liver cancer. Since repurposing MTX has the advantages of lower risk, shorter timelines, and less investment in drug discovery and development, a clinical trial is warranted to test its efficacy in the treatment of β-catenin mutant liver cancer.

Objective Based on the anthropomorphic phantom experiment and Monte Carlo simulation, the patients’ skin dose, professionals’ dose, and spatial distribution of DSA (Digital Subtraction Angiography) radiation field in an intervention procedure, was performed, in order to provide the basis for the inference of patients’ skin injury and professionals’ radiation protection in intervention procedure. Methods In the simulation experiment, a PBU-60 anthropomorphic phantom was used as the patient and the skin dose of patient’s abdomen was measured by TLD (Thermoluminescence Dosimeters). X-ray and gamma radiation dosimeter (AT1121) was applied to measure the spatial distribution of DSA radiation field, which was verified using Monte Carlo software MCNP meanwhile. Furthermore, the radiation dosimetry of operative staffs at different stations and under different protection conditions was studied experimentally. Results The experimental measurements showed that the maximum skin dose of patients every 5-minute fluoroscopy was 18.62 mGy under the irradiation of PA in an abdominal interventional procedure. The results of Monte Carlo simulation and measurement experiments showed that the spatial distribution of DSA radiation fieldis similar to the butterfly distribution, which is related to distance and angle. The experimental results showed that the dose rate decreases exponentially with the increase of lead equivalent. Conclusion It is very significant to carry out skin dose measurementof patients during interventional surgery and follow-up patients with high dose after surgery. In interventional surgery, doctors should try to avoid the station of high dose rate. However, it is necessary to strengthen the radiation protection of the operator and the first assistant. Under the dual protections of bedside lead protective equipment and personal protective equipment, the exposure dose of intervention personnel can be significantly reduced.