Objective:To develop an economical,simple and portable device for imitation of ship shock motion produced by non-contacting under water explosion.Methods:The device was developed based on aerodynamical principles and sensor detection technology,and was tested with animal experiments to verify its performance.The injuries caused by 4 grades of shock motions with different accelerations,duration and displacement were observed in 40 black rabbits(10 for each grade).Results:The device was safe and functionally stable,with a peak acceleration of 1 000 m/s~2,a shock duration of about 2 ms and a device displacement of 100 mm.The accelerations of 4 shock motion grades were significantly different and with good reproducibility.The damage to the rabbits were mainly haemorrhage of different extents in organs of pleuroperitoneal cavity,especially in the lungs,but no rupture of organs was found.The degree and involvement of damage had an increasing tendency with the increase of acceleration of shock motion.Conclusion:The device we developed can imitate the effects of ship shock motion.

Objective:To investigate the possible role of miR-181d in regulating the multidrug resistance (MDR) of small cell lung cancer (SCLC) and its clinical significance. Methods: Quantitative reverse transcriptase-polymerase chain reaction (QRT-PCR) and Western blot were used to investigate the differential expression of miR-181d and BCL2 from mRNA and protein levels in the chemo-sensitivity cell H69 and the chemo-resistance cell H69AR. The miR-181d expression in H69AR was then upregulated. More-over, CCK8 assay was employed to detect the sensitivities of the cells to chemotherapy drugs, such as ADM, DDP, and VP-16. Mean-while, the expression of miR-181d in the specimens of 87 cases with SCLC were detected using QRT-PCR. All patients received the chemotherapeutic regimen of EP (etoposide+cisplatin). Correlation of the miR-181d expression with clinicopathological features, prog-nosis, and survival time of the patients was studied. Results:miR-181d was downregulated in the SCLC multidrug-resistant cell line H69AR and chemo-resistant patients. Moreover, miR-181d was concurrent with the upregulation of BCL2 protein compared with the parental H69 cell line and chemo-sensitive patients (P<0.001). miR-181d expression in H69 cells resistant to chemotherapy drugs (ADM, DDP, and VP-16) was inhibited (P<0.01). Enforced miR-181d expression reduced the BCL2 protein level and sensitized H69AR cells to chemotherapy drugs (P<0.01). miR-181d expression was associated with tumor stage, sensitivity of chemotherapy, and survival time (all P<0.001). Patients with high miR-181d expression had longer overall survival and progress-free survival time com-pared with those with low miR-181d expression (P<0.001). Conclusion: miR-181d may play a role in the development of MDR in SCLC and may be a potential predictive factor for treatment efficacy.

Background Antigen retrieval method is the key of improving the successful rate of immunohistochemical assay in paraffin sections.To study an available method of antigen retrieval is a goal to achieve both good immunochemistry result and preserving retinal proteins.ObjectiveThe aim of present study is to investigate tyrosin digestion,high-temperature heat pressure,water bath heating and microwave repair in antigen retrieval for retinal tissues.MethodsRetinal tissue was isolated and obtained from clean Chinchilla rabbits.Four hundreds retinal paraffin sections were prepared.Four kinds of antigen retrieval methods for retinal tissue including tyrosin digestion,high-temperature heat pressure,water bath heating and microwave repair were used respectively.The depigmentated retinal paraffin section without antigen retrieval was used as control.The positive rates of expression of CRALBP,Rhodopsin and opsin proteins were evaluated and compared among four kinds of antigen retrieval methods by immunochemistry.ResultsCRALBP,Rhodopsin and opsin protein was positively expressed in cytoplasm of retinal pigment epithelial cells and the outer segment of photoreceptor respectively.No significant difference was found in the positive expression rates of these three proteins among four kinds of antigen retrieval methods (P＞0.05),but the differences in tissue integrity and background staining were statistically significant (P＜0.01).The structural damage of retina included loss and pucker of scalera,crack of nucleus and abnormal background stain in high-temperature heat pressure method,water bath heating method and microwave retrieval method.However,stable CRALBP,Rhodopsin and opsin protein expression and strain effectiveness,clear background without unspecific staining and integrated tissue were seen in tyrosin digestion method.ConclusionDuring the clinical pathology analysis of retinal tissue,the application of tyrosin digestion in antigen retrieval could obtain a better effectiveness.

Objective To observe the curative effects of anti-vascular endothelial growth factor (anti-VEGF) intracameral and intravitreal injection,trabeculectomy and pan-retinal photocoagulation by indirect ophthalmoscope for neovascular glaucoma (NVG).Methods NVG patients with uncontrolled intraocular pressure (IOP) and retinopathy was enrolled from May,2014 to May,2016.Eighteen patients were enrolled with 15 males(15 eyes) and 3 females(3 eyes) with age at (61.7 ± 13.9) years old.Anti-VEGF intracameral and intravitreal injection with anterior chamber puncture was performed in the first day of sequential treatment.Trebeculectomy was performed 3-5 days after injection and finally the pan-retinal photocoagulation was started 5-7 days after anti-glaucoma surgery.The best corrected visual acuity (BCVA),IOP,cornea,neovascularization of iris and retinal disease were observed and recorded.Results The diagnosis included 1 eye with central retinal artery occlusion (CRAO),6 eyes with central retinal vein occlusion (CRVO),5 eyes with branch retinal vein occlusion,5 eyes with proliferative diabetic retinopathy and 2 eyes with combined CRAO and CRVO.IOP before and after treatment were (43.5 ±5.1) mmHg (1 kPa =7.5 mmHg) and (15.2 ± 2.2) mmHg,there was significantly statistical difference (t =21.68,P ＜0.001).The categories of antiglaucoma medicines were 5.1 ± 0.5 and 0.5 ± 1.0 before and after treatment respectively,and the difference was statistical significant (t =12.30,P ＜ 0.001).BCVA was improved in 4 eyes,maintained in 13 eyes and decreased in only 1 eye.Conclusion The sequential treatment including anti-VEGF intracameral and intravitreal injection,trabeculectomy and pan-retinal photocoagulation by indirect ophthalmoscope is safe and effective.

ObjectiveTo investigate bone marrow mesenchymal stem cells(BMSC) express brain derived neurotrophic factor(BDNF) and nerve growth factor(NGF) and their protective effect for neural stem cells (NSCs).MethodsBMSC were obtained from rat tibiae and femurs and centrifuged with Ficoll. The passage 3 cells were chosen to make immunocytochemical stain for CD44, CD71 and CD45. The expression of BDNF and NGF was detected in BMSC with RT-PCR, as well as in the media with ELISA. The media that cultured BMSC were collected as BMSC condition media. NSCs were obtained from cerebral cortex of new-born rat and cultured in vitro. After different ratio of BMSC condition midia were added, NSCs were induced to apoptosis with heat-shock, then NSCs were dyed with Annexin V-FITC/PI apoptosis kit and apoptosis rates were tested with flow cytometry. ResultsBMSC were CD44(+), CD45(-), CD71(+) and expressed BDNF and NGF mRNA. BDNF and NGF could be tested in the media of cultured BMSC and increase with cultured time. BMSC condition media could reduce the ratio of heat-induced apoptosis of NSCs, and more BMSC condition media showed better effect. ConclusionBMSC can express neurotrophic factores and protect neural stem cells from heat-induced apoptosis.

Cellulases are relatively costly enzymes that are sold in large volumes for use in different industrial applications, and a significant reduction in cost will be important for their commercial use in biorefineries. The production of cellulase is a major factor in the hydrolysis of cellulosic materials. Hence it is essential to make the process economically viable. A strain (L-06) with high cellulase activity was screened from rice straw compost and classified as Penicillium decumbens by the analysis of its morphology and 18S rRNA gene sequences. Different conditions of liquid fermentation medium including nitrogen source, carbon source, surfactant, temperature, initial pH, inoculation quantity for the production of cellulase had been studied. The maximal beta-1, 4-glucosidase(BGL) activity was 1662 u/mL which is 1.49 times of the previous and the maximal exo-beta-1, 4-glucanases(CBH) activity was 2770 u/mL which is 1.36 times of the previous, cultured in the optimal condition for three days. And the maximal endo-beta-1, 4-glucanases (EG) activity was 18064 u/mL which is 1.87 times of the previous and the maximal filter paper enzyme(FPase) activity was 4035 u/mL which is 1.47 times of the previous, cultured in the optimal condition for four days. In the optimization experiments, the EG and CBH in the culture condition (pH10) maintained 70% and 43% activity. In the culture condition (50 degrees C) EG and CBH maintained 59% and 68% activity, which showed heat and alkali resistant characteristics.
Cell Culture Techniques ; Cellulase ; biosynthesis ; isolation & purification ; metabolism ; Cellulose ; metabolism ; Glucan 1,4-beta-Glucosidase ; biosynthesis ; metabolism ; Oryza ; Penicillium ; cytology ; enzymology ; isolation & purification ; Plant Stems ; microbiology ; Temperature ; beta-Glucosidase ; biosynthesis ; metabolism

BACKGROUND:Human mesenchymal stem cells derived from Wharton's jelly(WJCs)display the characteristics of MSCs as defined by the International Society for Cellular Therapy.They can be differentiated into bone,cartilage,adipose,muscle,and neural cells.They can also support the expansion of other stem cells,be weli-tolerated by the immune system,and have the ability to home to tumors.OBJECTIVE:To investigate biological changes of WJCs and brain tumor stem cells(BTSCs)co-cultured in vitro.METHODS:WJCs cultured by situ cultivation and BTSCs used enzyme digestion way respectively,and gathering the 3rd passage of WJCs though subculturing as well as BTSCs.Two kinds of cells co-cultured in 24-well plates in serum-free medium (SFM)without any growth factor.3 and 7 days after co-cultured respectively,CD133 expression of suspension cells in the 24-well plates were identified by flow cytometry,and immunofluorescence was performed for Nestin and glial fibrillary acidic protein (GFAP)expression of adherent cells.Co-culture supernatant(CCS)re-suspended 3~(rd) passage of BTSCs and cultured into 96-well plates at day 3,which were used to determine the difference in cell growth curve in both groups using a microplate reader.RESULTS AND CONCLUSION:With the cocultivation days increasing,the phenomenon that tumor sphere cells began to be decomposed,adherent and differentiated observed by an inverted microscope.BTSCs in the co-cultured group expressed GFAP and Nestin when adherent and differentiated.The higher degree of malignant brain tumor tissue used in culturing BTSCs was,the higher expression of CD133 in BTSCs was.CD 133~+ in BTSCs declined when co-cultured with WJCs.Growth curve of brain tumor stem cells cultured in CCS compared with in SFM at day 3,which indicates that the proliferation of BTSCs inhibited obviously.Results indicated that CD 133~+ expression and proliferative capacity of BTSCs went down and BTSCs underwent differentiation during the co-culture in vitro.

Objective To analyze the etiologies of severe vitreous hemorrhage in venerable age patients.Methods A retrospective series case study was adopted.Medical records of 30 cases 30 eyes severe vitreous hemorrhage venerable age patients were analyzed in Xuanwu Hospital Capital Medical University,Peking University Third Hospital and Beijing Tsinghua Chang Gung Hospital from July in 1999 to June in 2015.Visual acuity,intraocular pressure,anterior segment slit lamp microscopy,mydriasis funduscopy and ophthalmic B type ultrasound examination were used to evaluate 30 cases 30 eyes.Thirty eyes were all treated with pars plans vitrectomy (PPV).Results Mydriasis funduscopy examination showed that vitreous hemorrhage was so dense in 30 eyes that the fundus cannot be observed.The initial visual acuity examination showed that 8 eyes were count finger,5 eyes were hand move,16 eyes were light perception,and 1 eye was no light perception.There were dense light spots or clusters of high echoes in vitreous cavities,complete/incomplete posterior vitreous detachment (PVD) of all eyes;retinal detachment with different degrees in 5 eyes;proliferating cord adhesion to the wall of eyeball in 3 eyes.The etiologies included retinal vein occlusion (RVO) in 10 eyes (33.33％),retinal tear or retinal detachment in 7 eyes (23.33％),polypoidal choroidal vasculopathy (PCV) in 7 eyes (23.33％),proliferative diabetic retinopathy (PDR) in 4 eyes (13.33％).The above 4 etiologies were in 28 eyes,accounting for 93.33％.The others were ocular trauma in 2 eyes (6.67％).Conclusions The main cause to severe vitreous hemorrhage venerable age patients is RVO,followed by retinal tear or retinal detachment,PCV and PDR.Ocular trauma is rare.Vitrectomy is a diagnostic treatment,which can remove vitreous hemorrhage,improve the visual acuity of the patients,and determine the etiologies of the vitreous hemorrhage.

In recent years, with the in-depth study of PD-1 and PD-L1 and the development of immunotherapy, the first problem is how to screen the beneficiaries. Recent clinical studies have shown that the expression level of PD-L1 in circulating tumor cells (CTC) can be used as a potential biomarker to play a guiding role in immunotherapy of malignant tumors. This article reviews the latest clinical research progress on the expression of PD-L1 in circulating tumor cells in various solid tumors.

Objective:To evaluate the value of radiomics analysis based on enhanced MRI in predicting the recurrence of acute pancreatitis (AP).Methods:From January 2017 to December 2020, 201 patients diagnosed with AP were collected retrospectively in the Affiliated Hospital of North Sichuan Medical College. These patients underwent plain and enhanced MRI within 7 days after onset. After clinical follow-up, 102 cases were classified as non-recurrence AP group and 99 cases were classified as recurrent acute pancreatitis (RAP) group. They were divided into training set (140 cases, 71 cases in non-recurrence AP group, 69 cases in RAP group) and validation set (61 cases, 31 cases in non-recurrence AP group, 30 cases in RAP group) using a random number table method. The independent sample t-test, Mann-Whitney U test or χ 2 test were used to compare the clinical characteristics between the two groups, and the clinical characteristics with statistical differences were included in logistic regression to construct the clinical model. The quantitative features of radiomics were extracted based on the late arterial-phase images of contrast-enhanced MRI. The best radiomics features retained after dimensionality reduction were used to construct the radiomics model through logistic regression analysis, and a combined model was constructed by combining the clinical features. The prediction ability of the models was evaluated by the receiver operating characteristic curve, and the area under the curve (AUC) was compared by DeLong test. Results:There were statistical differences in gender, severity, local complications, hyperlipidemia and smoking between non-recurrence AP group and RAP group (all P<0.05). Hyperlipidemia was an independent risk factor for AP recurrence (OR=5.236, 95%CI 2.710-10.101). The 9 best radiomics features by dimensionality reduction were selected to construct a radiomics model. The AUCs of clinical model, radiomics model and combined model in the training set were 0.803, 0.944 and 0.978 respectively, and those in the validation set were 0.678, 0.940 and 0.955 respectively. In the training set and the validation set, the prediction ability of the radiomics model and combined model were higher than those of the clinical model (training set: Z=3.28, 4.83, P=0.001,<0.001; validation set: Z=3.48, 4.05, both P<0.001). Conclusions:The radiomics model based on late arterial-phase enhanced MRI has good quantitative prediction ability for the recurrence of AP, which can provide a reference for the prevention and treatment of RAP.