Application of conditional inference forest in time-to-event data analysis / 南方医科大学学报

OBJECTIVE@#To explore the application and advantages of conditional inference forest in survival analysis.@*METHODS@#We used simulated experiment and actual data to compare the predictive performance of 4 models, including Coxproportional hazards model, accelerated failure time model, random survival forest model and conditional inference forest model based on their Brier scores.@*RESULTS@#Simulation experiment suggested that both of the two forest models had more accurate and robust predictive performance than the other two regression models. Conditional inference forest model was superior to the other models in analyzing time-to-event data with polytomous covariates, collinearity or interaction, especially for a large sample size and a high censoring rate. The results of actual data analysis demonstrated that conditional inference forest model had the best predictive performance among the 4 models.@*CONCLUSIONS@#Compared with the commonly used survival analysis methods, conditional inference forest model performs better especially when the data contain polytomous covariates with collinearity and interaction.

Subgroup identification based on an accelerated failure time model combined with adaptive elastic net / 南方医科大学学报

OBJECTIVE@#We propose a strategy for identifying subgroups with the treatment effect from the survival data of a randomized clinical trial based on accelerated failure time (AFT) model.@*METHODS@#We applied adaptive elastic net to the AFT model (designated as the penalized model) and identified the candidate covariates based on covariate-treatment interactions. To classify the patient subgroups, we utilized a likelihood-based change-point algorithm to determine the threshold cutoff point. A two-stage adaptive design was adopted to verify if the treatment effect existed within the identified subgroups.@*RESULTS@#The penalized model with the main effect of the covariates considerably outperformed the univariate model without the main effect for the trial data with a small sample size, a high censoring rate, a small subgroup size, or a sample size that did not exceed the number of covariates; in other scenarios, the latter model showed better performances. Compared with the traditional design, the adaptive design improved the power for detecting the treatment effect where subgroup effect exists with a well-controlled type Ⅰ error.@*CONCLUSIONS@#The penalized AFT model with the main effect of the covariates has advantages in subgroup identification from the survival data of clinical trials. Compared with the traditional design, the two-stage adaptive design has better performance in evaluation of the treatment effect when a subgroup effect exists.

Protective Effect of Water-soluble Total Flavonoids from Isodon Lophanthoides var.gerardianus ( Benth.) H.Hara on H2 O2-induced LO2 Cells Damage / 中国药师

Objective:To explore the protective effect of the water-soluble total flavonoids from Isodon lophanthoides var.gerardia-nus (Benth.) H.Hara on LO2 cells damage.Methods:The cytotoxicity was evaluated by MTT cell viability determination to confirm the concentration range .Hepatocyte damage model was established by H 2 O2 treatment.After the oxidative stress hepatocyte was coin-cubated with WSTF at different concentrations for various times , the protective effect of WSTF on H 2 O2-induced hepatocyte damage was evaluated by MTT cell viability determination and the content determination of ALT , AST and MDA in cell supernatant .The inhibition of WSTF against H 2 O2-induced LO2 cells apoptosis was evaluated by the quantitative determination of Rhodamine 123 fluorescence and intracellular ROS.Results:The LO2 cells injured by 0.3 mmol· L-1 H2 O2 treatment for 4 h were used as the hepatocyte damage model.The concentration range of WSTF was 0.0312-0.125 mg· ml-1.WSTF could inhibit H2O2-induced injury in LO2 cells and obviously reduce ALT, AST and MDA.Moreover, WSTF could reverse mitochondrial membrane potential depolarization and decrease the amount of intracellular ROS .Conclusion:WSTF exhibits notable protective and curative effects on hepatocyte damage in vitro.

Multi-slice CT imaging analysis of basal cell adenoma in the parotid gland / 中国基层医药

Objective To investigate the CT imaging features of basal cell adenoma in the parotid gland and thus to improve the preoperative diagnostic accuracy.Methods The clinical materials and image findings of 8 cases with parotid basal cell tumor,which were proved by pathology,were retrospectively studied.Results All 8 patients had solitary BCA lesion,which involved both the superficial and deep lobe(n =1) and located at the superficial lobe of parotid gland(n =7).All the 6 tumors were clear boundary and round shape without lobular appearance.The diameters of the max lesions ranged from 10.3-27.6 mm.CT scan showed that all lesions were solid nodules with uniform or uneven density.Cystic degeneration was displayed in 5 lesions,among them,cystic area was ≥90％ in 1 lesion.At enhanced scanning phase,most tumors showed a strong enhancement at the arterial phase and a pattern of persistent strong enhancement or slow decline at the venous phase.Conclusion The multi-slice CT imaging features of BCA in parotid gland are characteristic,which is helpful to make qualitative diagnosis in combination with clinical materials.

Epidemiological analysis for prehypertension and its risk factors in community of Changsha / 中南大学学报(医学版)

OBJECTIVE@#To explore the epidemiological features of prehypertension in community of Changsha and its relevant risk factors.
@*METHODS@#A total of 15 000 participants from 5 communities in Changsha were surveyed by randomly stratified cluster sampling. The questionnaire interviews and physical examination were conducted for these people, and their serum biochemical indexes were also collected and analyzed.
@*RESULTS@#The prevalence of prehypertension was 34.6%. The prevalence for males was higher than that in females (44.7% vs 21.7%, P<0.01). The prevalence for males was declined in older age, but for females was increased. Central obesity, age, overweight, male, drinking, smoking, high-level total cholesterol, high-level triglyceride, high-level density-lipoprotein cholesterol, low-level density-lipoprotein cholesterol, high-level fasting blood glucose, high-level creatinine, high-level uric acid were the risk factors for prehypertension, while high level of education was a protective factor.
@*CONCLUSION@#The prevalence for prehypertension is 34.6% in community of Changsha, and the prevalence for males is higher than that for females. It is important to strengthen the health publicity and education in community for earlier prevention.

Prognostic factors analysis of 133 patients with brain glioma / 重庆医学

Objective To explore the prognosis and related factors of brain glioma .Methods 133 patients who have been con-firmed pathology with brain glioma from Jan .2001 to Dec .2010 were retrospectively analyzed .The factors such as sex ,age ,func-tional status ,histological character ,the longest diameter of tumor ,surgical excision of part or all of the tumor ,whether or not being radiotherapy after surgical excision were selected to evaluate by single factor and multiple factors analysis .Results The median fol-low-up time was 36 months ,The follow-up rate was 93% .73 cases were followed up for 3 years ,the 1- ,2- and 3- year survival rate was 93% ,82% and 70% ,respectively ,the median survival time was 62 .7 months .Multiple factors regression analysis showed that histological character ,the longest diameter of tumor and whether or not being radiotherapy after surgical excision were related to prognosis .Conclusion High-grade of histological character ,the longest diameter of tumor≥6 cm predict poor prognosis ,postop-erative radiotherapy can improve the survival of glioma .

Treatment outcomes of different radiotherapies for postoperative gliomas：three-dimensional conformal radiotherapy versus conven-tional radiotherapy / 中国肿瘤临床

10.3969/j.issn.1000-8179.2013.12.010

Serum thymidine kinase 1 measurement in health check-up / 中华健康管理学杂志

Objective To evaluate the utility of serum thymidine kinase 1(STK1)in health screening.Methods A total of 8896 adults who participated in health check-up during November 2009 and November 2010 were tested for STK1 by using sensitive chemiluminescence's dot blot assay.Results The level of STK1 of group A(STK1 ＞ 2 pmol/L)was much higher than that of the group B(STK1 ＜ 2 pmol/L)[(5.47 ±4.23)vs(0.62 ±0.48)pmol/L;t =11.90,P =0.00].The STK1 level was not correlated with gender.However,the mean age of individuals in the group A was higher than that in the group B[(48.2 ± 12.0)vs(41.8 ± 12.3)years; t =5.37,P =0.00].The positive detection rate of STK1 was 1.2％(108/ 8896).In the group A,there were 1.9％ pre-or post-treatment malignancy,27.8％ pre-malignant tumor or benign disease,36.0％ nontumorous proliferation disease,14.8％ hepatitis B virus/HP infection,10.2％fatty liver,and 9.3％ other diseases.No pre-treatment malignancy and pre-malignancy were found in the group B.Conclusion STK1 measurement could reflect the situation of cell proliferation and predict the risk of any type of malignancy.

Xenotransplantation of Microencapsulated Rabbit Parathyroid Tissue for Treatment of Hypoparathyroidism In Rats / 中国普外基础与临床杂志

Objective To investigate the effect of xenotransplantation of microencapsulated rabbit parathyroid tissue in different sites in rats for the treatment of hypoparathyroidism. Methods The parathyroid glands from Wistar rats were removed to make them aparathyroid. Ultimately, sixteen rats were included because their serum calcium values were continuously below 1.6 mmol/L. We also encapsulated the cultured rabbit parathyroid tissue with alginate-BaCl2 microcapsule. According to the transplantation sites, rats were randomly divided into two groups: renal adipose microcapsule group and peritoneal microcapsule group, eight in each group. Encapsulated rabbit parathyroid tissues were then transplanted accordingly to different microcapsule groups. The calcium serum contents were examined on 5,15,25,35,45,55 and 65 d respectively after transplantation and the grafts were observed through electron microscope on the 65 d in particular. Results The calcium contents after transplantation in renal adipose microcapsule group restored to normal and the observation outcomes of grafts showed that they survived well. The calcium contents of posttransplantation in peritoneal group also restored to normal with an exception that it dropped to a level lower than 1.6 mmol/L on the 65 d. Electron microscope also showed that there were necrotic tissues in the center and only a few cells survived on the edge of the grafts. Within peritoneal microcapsule group, the values were significantly lower than others taken at different phases. Conclusion Microencapsulated rabbit parathyroid tissue that was xenotransplanted into rats can survive and function without administration of immunodepressant. There are significant differences of calcium contents at varying phases between two transplantation sites, which demonstrate that renal adipose may be an optimal site for microcapsule xenotransplantation.

Chemical components of Rumex gmelini (Ⅳ) / 中草药

Objective To study the chemical constituents from the root of Rumex gmelini.MethodsThe compounds were isolated and purified by chromatography,polyamide column chromatography,and preparation HPLC etc.Their structures were elucidated by physicochemical and spectroscopic evidences.Results Ten compounds were identified as:nepodin (Ⅰ),emodin (Ⅱ),citreorosein (Ⅲ),chrysophanol 8-O-?-(6'-acetyl) glucopyranoside (Ⅳ),chrysophanol 8-O-?-D-glucopyranoside (Ⅴ),resveratrol (Ⅵ),9,9'-dianthranone-2,2'-dimethyl-5,5'-bis (?-D-glucopyranose)-9,9',10,10'-tetrahydro-4,4'-dihydroxy-10,10'-dioxo (trivial name:rumoside A) (Ⅶ),emodin-8-O-?-D-glucopyranoside (Ⅷ),resveratrol-3-O-?-D-glucoside (Ⅸ),and rutin (Ⅹ).Conclusion Compound Ⅶ is a new compound,named rumoside A.Compounds Ⅴ,Ⅷ,and Ⅹ are separated from R.gmelini for the first time.Compounds Ⅲ and Ⅳ are the compounds which have been found in the plants of Rumex L.for the first time.

Expression changes in flagellin and monocyte TLR5 mRNA in the peripheral blood of patients with sepsis / 解放军医学杂志

20/min,PaCO2 12?109 or 0.10.26 patients with sepsis infected by Gram negative bacilli were categorized as G-group,15 infected by Gram positive coccus as G+ group and 15 healthy persons as control group.All the cases were proved to have infection by body fluid examination under microscope or bacterial culture.The level of flagellin was determined by ELISA.The peripheral blood mononuclear cells(PBMC)were isolated by the density gradient centrifugation,and total RNA of PBMCs was extracted by RNA BIOzol extract.The level of TLR5 mRNA in the peripheral blood was detected by semi-quantitative RT-PCR.The statistic significance among groups was examined by Students' t test.Results Plasma flagellin levels were below the detection limit of the ELISA kit in both G+ and control groups,while the mean level of plasma flagellin amounted to 6.636?5.147ng/ml in G-group.TLR5 mRNA expression in G-group was significantly higher than that in G+ and control groups,and no significant difference was found between G+ group and control group.Conclusion Flagellin may be involved in the development of ALI through interacts with TLR5.