DNA methylation is the best studied of the epigenetic changes that influence the gene expression,and changes in genomic methylation patterns have been observed in many cancer cell lines.Nutrients as methyl donors play essential roles in DNA methylation and may modify cancer risk.This review,with an emphasis on the relationship between nutrition,DNA methylation and cancer,firstly defines methylation with a description of its correlated mechanism,then approaches the molecular mechanism of cancer initiation and development at the methylation level,and lastly summarizes the mechanism underlying the effect of methylation-related nutrients on the process of cancer initiation and development at the molecular level.It also offers some suggestions on cancer prevention at the group nutrition level.

Objective To investigate the risk factors,management and prophylaxis of dangerous placenta previa.Methods The clinical data of 407 cases of placenta previa were reviewed,36 cases of them with dangerous placenta previa.Comparison was made between group A (dangerous placenta previa,36 cases) and group B (non dangerous placenta previa,371 cases) in terms of age,number of pregnancy and number of ceasarean delivery.Results The incidence rates of pregnant women in group A age ≥ 35years,number of pregnancy ≥3times,and cesarean delivery≥2times were 55.6％,61.1％,25.0％,which were significantly higher than those of group B (25.6％,27.7％,2.4％),the differences were statistically significant (x2 =7.71,8.99,21.97,all P ＜ 0.01).Among the 36 cases of dangerous placenta previa,12 cases were diagnosed with concomitant placenta increta.The specificity and sensitivity for detection of placenta increta were 90.5％ (19/21) and 83.9％ (10/12) of ultrasonography respectively,and those were 100.0％ (3/3) and 87.5％ (7/8) of MRI.Of the 36 dangerous placenta previa patients,two patients were treated with induced labour due to unexpected pregnancy under 28 weeks,while the others were refer to surgical operation.5 surgical patients experienced uncontrollable postpartum haemorrhage which necessitated histectomy,while the other 31 cases received conservative operation.Rate of histectomy was 13.9(5/36).Conclusion Dangerous placenta previa is associated with advanced age,multiple pregnancy and multiple cesarean delivery.Accurate preoperational evaluation of the placenta previa should be acquired with ultrasonography and MRI to detect placenta increta,provide information for treatment selection,and prevent postpartum haemorrhage.

A novel method for accurate,fast and sensitive detection of pesticides such as imidacloprid,isocarbophos,phoxim,dursban,imidacloprid,pyridaben and avermectin in environmental water samples has been developed by using ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) coupled with high performance liquid chromatography with ultraviolet detection (HPLC-UV).The UA-DLLME parameters such as types/volumes of extraction/dispersion solvents,ultrasonic time,ionic strength and extraction time were investigated.Under the optimized extraction conditions,the linearity for the detection of six pesticides in the concentration range of 10-600 μg/L was obtained with limits of detections (LODs) of 0.8-3.1 μg/L and relative standard deviations (RSDs) of 4.7％-11.3％.UA-DLLME method exhibited strong enrichment ability for the six pesticides,and the enrichment factor (EFs) were ranged from 58 to 187.This method had perfect linearity,precision and recovery results,and showed obvious advantages and practicality comparing the previously reported methods.

Objective To investigate the association of hepatitis B virus ( HBV) precore ( preC) /C mutations with the pro-gression of liver disease .Methods The HBV genes of 50 chronic hepatitis B , including 30 HBV e-antigen ( HBeAg)-negative and 20 HBeAg-positive patients, were detected with real-time quantification polymerase chain reaction (RT-PCR) and the direct sequencing method.Results The mutations T1762/A176, T1766/A1768, A1896 , and the levels of HBV viral loads significantly correlated with the disease progression .The HBeAg-negative patients had a higher frequency of mutations at T 1762/A1764 , T1766/A1768 , and A 1896 relative to HBeAg-positive patients .Conclusions Patients with advanced liver diseases and with HBeAg-negativity possibly had multi-mutations at T1762/A1764, T1766/A1768, and A1896 in HBV genomes.

Objective To investigate the dynamic changes in intestinal alpha-defensin-5 (RD-5),beta-defensin-2 (BD-2) mRNA after acute liver failure(ALF),and to explore their role in ALF.Methods A total of 60 C57BL5 mice were divided into 4 groups by means of random number table method:normal control group,ALF group,E.coli via gavage group and ALF + E.coli via gavage group.Intraperitoneal injection of D-galactosamine (500 mg/kg) and lipopolysaccharide(10 μg/kg) to make the model,in addition,ALF mice were fed with E.coli,and the observation time was 6 hours,12 hours,and 24 hours after modeling,and each time point had 6 specimens.Real-time PCR was used to test the RD-5 mRNA and BD-2 mRNA levels in the ileum tissue.Results The levels of RD-5 and BD-2 showed dynamic change in the experiment of ALF.Compared with the levels of RD-5 and BD-2(11.25 ±0.74,23.86 ±0.39) of the normal control group,the levels of RD-5 and BD-2 in ALF group and E.coli via gavage group increased at 6 hours after modeling(14.19 ±0.39,26.79 ± 0.36 and 12.57 ± 0.68,26.45 ± 0.85),and the differences were significant(all P＜0.05);at 12 hours after modeling,the RD-5 and BD-2 reached to the maximum concentration(15.76 ±0.33,29.10 ± 0.61 and 12.90 ± 0.96,27.42 ± 0.71),and the differences were statistically signi-ficant (all P ＜ 0.05).The degree of elevation of BD-2 was higher than RD-5.Later,they gradually declined.Conclusions RD-5 and BD-2 may play an important role in the pathogenesis of intestinal endotoxemia in experimental ALF.

Myeloid cell leukemia-1 (MCL-1) is an anti-apoptotic protein that plays a key role in promoting cell survival in multiple myeloma, acute myeloid leukemia and non-Hodgkin lymphoma. MCL-1 is highly expressed in a variety of hematological malignancies, which is one of the important factors leading to poor prognosis and chemoresistance in patients with hematological malignancies. Therefore, MCL-1 is an important therapeutic target for hematological malignancies. Several MCL-1 inhibitors have entered clinical trials, including S63845, AZD5991, S64315, AMG-176, and AMG-397. The treatment plans used for hematological malignancies include monotherapy with MCL-1 inhibitors, as well as combination therapy with B cell lymphoma 2 inhibitors or immunomodulatory drugs, all indicating that MCL-1 inhibitors may be a breakthrough point for targeted treatment of hematological malignancies.

Objective:To study the dosimetric differences and short-term efficacy between intracavitary/interstitial brachytherapy (IC/ISBT) and conventional intracavitary brachytherapy (ICBT).Methods:Forty-five patients with locally advanced cervical cancer were treated with IC/ISBT and ICBT. Points A (A 1, A 2), D 90%, D 100%, organs at risk, and the doses of bladder, colon, rectum and small intestine were calculated and the short-term efficacy was observed between two groups. Results:Point A dose was significantly improved in IC/ISBT compared with ICBT ( P<0.05). The D 90% and D 100% in IC/ISBT were significantly higher than those in ICBT (both P<0.05). After brachytherapy, IC/ISBT could obtain a significantly larger increase in target dose when residual tumor diameter was ≥3 cm compared with ICBT ( P<0.05). The D 2cm 3 and D 0.1cm 3 of bladder, rectum, colon and small intestine did not significantly differ between IC/ISBT and ICBT (all P>0.05). The 1-, 3-and 6-month clinical efficacy did not significantly differ between two technologies (all P>0.05). Conclusion:During brachytherapy for locally advanced cervical cancer (residual tumor diameter ≥3 cm), IC/ISBT significantly increases the doses of target area and point A without increasing the dose of organs at risk or lowering the short-term clinical efficacy, which has significant dosimetric advantages.

Objective To observe the clinical efficacy of noninvasive ventilation (NIV) on the treatment of acute respiratory distress syndrome (ARDS) caused by severe pneumonia after kidney transplantation. Methods The clinical data of 17 patients who were diagnosed as ARDS caused by severe pneumonia after kidney transplantation and treated with NIV in Sichuan Provincial People's Hospital from January 1st, 2014 to June 1st, 2016 were collected and retrospectively analyzed. According to the result of NIV treatment, the patients were divided into NIV success group (n = 9) and NIV failure group (n = 8). The differences in gender, age, underlying diseases, acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) score, laboratory parameters on the day when ARDS was diagnosed, daily immunosuppressive dosage, NIV support condition and duration, arterial blood gas analysis and adverse reactions between the two groups were compared. Receiver operating characteristic curve (ROC) was plotted, and the predictive value of each parameters for NIV results was evaluated. Results The two groups were similar in gender, age, and underlying diseases. The APACHEⅡ score, serum levels of procalcitonin (PCT) and brain natriuretic peptide (BNP), serum creatinine (SCr), daily tacrolimus dose, and NIV support condition in NIV failure group were significantly higher than those in NIV success group [APACHEⅡscore: 16.7±5.7 vs. 10.3±2.1, PCT (μg/L): 32.8 (1.2, 187.7) vs. 0.3 (0.1, 2.9), BNP (ng/L): 832.4 (263.7, 1 180.2) vs. 157.0 (33.9, 218.5), SCr (μmol/L): 284.8 (90.5, 474.2) vs. 186.6 (76.7, 206.3), daily tacrolimus dose (mg): 3.6 (3.1, 4.0) vs. 2.6 (2.0, 3.5), inspiratory positive airway pressure (IPAP,cmH2O, 1 cmH2O = 0.098 kPa): 14.8±4.1 vs. 9.0±1.1, expiratory positive airway pressure (EPAP, cmH2O): 7.6±1.8 vs. 4.7±0.8, fraction of inspired oxygen (FiO2): 0.75±0.25 vs. 0.43±0.06, all P < 0.05], and the oxygenation index (PaO2/FiO2) after treatment was significantly lower than that of NIV success group [mmHg (1 mmHg = 0.133 kPa):107.4±65.2 vs. 268.7±98.8, P < 0.05]. There was no significant difference in albumin (Alb), white blood cell count (WBC), daily mycophenolate mofetil dose, use of glucocorticold, NIV duration, pH value, arterial partial pressure of carbon dioxide (PaCO2), or the incidence of sputum drainage disorder or pneumothorax between the two groups. ROC curve analysis showed that the predictive value of APACHEⅡ score, serum PCT and BNP levels, tacrolimus daily dosage and PaO2/FiO2changes after NIV treatment for the efficacy of NIV was high, the area under the ROC curve (AUC) was 0.813, 0.778, 0.903, 0.778, 0.764, respectively; when the cut-off value of APACHEⅡ score was 16.0, PCT was 4.1 μg/L, BNP was 180.5 ng/L, tacrolimus daily dosage was 2.5 mg, PaO2/FiO2increased 49.5 mmHg, the sensitivity was 87.5%, 75.2%, 87.5%, 87.5% and 75.0%, respectively, and the specificity was 77.8%, 66.7%, 88.9%, 74.4%, 88.9%, respectively. However, SCr was not sensitive to the NIV effect prediction. Conclusions NIV in the treatment of ARDS caused by severe pneumonia after kidney transplantation has a certain value. The fewer tacrolimus daily dosage, the lower APACHE Ⅱ score and levels of PCT and BNP, the more effective promotion of PaO2/FiO2after NIV treatment, and the better curative effect is suggested.

Objective:To measure the anatomical parameters of the simulated low tibial tunnel of posterior cruciate ligament (PCL) based on knee CT images so as to provide clinical reference for accurate location of the tunnel.Methods:The CT images of 201 healthy knee joints collected at Department of Orthopedics, The Second Hospital of Lanzhou University from June 2016 to September 2021 were used for simulation of the PCL low tibial tunnel. The anatomical parameters of the tibial tunnel were measured using the RadiAnt DICOM Viewer. The primary measures included the angle between tibial plateau and tibial tunnel (ATPT) and the perpendicular distances from the tibial tunnel entrance and exit point to the tibial plateau (L1 and L2). The secondary measures included the angle between tibial plateau and posterior slope (PSA), the angle between tibial anatomical axis and central line of tibial tunnel (ATAA), the angle between posterior tibial slope line and the central line of tibial tunnel (APST), the anterior and posterior diameter of tibial plateau (APD), the length of posterior tibial slope (LPTS), and the length of tibial tunnel (LTT). The measurement results were analyzed according to the body height (divided into 3 groups: a 1.00 to 1.60 m group, a 1.61 to 1.70 m group, and a ≥1.71 m group) and gender using the software IBM SPSS 26.Results:The primary measures: ATPT was 37.0°±4.5°, and L1 and L2 were respectively (57.8±7.4) mm and (34.5±3.3) mm. The secondary measures: PSA 128.1°±5.4°, ATAA 52.7°±4.1°, APST 89.1°±5.9°, APD was (32.9±2.6) mm, LPTS (20.5±2.4) mm, and LTT (40.9±5.7) mm. After grouping by gender, there was no significant difference in PSA between men and women ( P>0.05) while there were significant differences in the other indexes between men and women ( P<0.05). After grouping by body height, there was no significant difference in ATPT, PSA, APST or ATAA between the 3 groups (1.00 to 1.60 m group, 1.61 to 1.70 m group and ≥1.71 m group) ( P>0.05) while there were significant differences in L1, L2, APD, LPTS and LTT between the 3 groups ( P<0.05). Conclusions:Based on the knee CT images, the primary measures of PCL low tibial tunnel are as follows: the angle between tibial plateau and tibial tunnel is 37.0°±4.5°, and the perpendicular distances from the tibial tunnel entrance and exit point to the tibial plateau are (57.8±7.4) mm and (34.5±3.3) mm, respectively. Gender and body height are the important factors influencing the above measurement outcomes.

Objective To investigate the effects of olanzapine combined with metacognitive training on social cognition and insight of schizophrenic patients.Methods One hundred twenty patients with schizophrenia were randomly divided into two groups. All patients received four week treatment. The study gr oup received olanzapine combined metacognitive training treatment and the control group only used olanzapine treatment. The positive and negative symptoms scale (PANSS), the Insight and Treatment Attitude Questionnaire (ITAQ), the Beck Cognitive Insight Scale (BCIS) and Faux Pas Recognition Task (FPRT) were assessed at baseline and after four weeks of treatment. Result There was no statistically significant difference in the scores of all battery between two groups before treatment (P>0.05). the scores of total PANSS and subscales, ITAQ, BCIS and FPRT were statistically significant between study and control groups (P<0.05).After 4 weeks of treatment,the total PANSS scores and subscales scores were significantly lower in the study group than in the control group (P<0.05). The ITAQ score, self-reflection factor of BCIS, composite index and FPRT scores were significantly higher in the study group than in the control group (P<0.05). The difference in self-certainty of BCIS difference was not statistically significant(P>0.05).Differences of the remaining scales were statistically significant(P<0.05). Conclusion Olanzapine combined with metacognitive training has a significant effect on the social cognitive dysfunction in schizophrenic patients,improving the patient's insight and enhancing the social function.