Mechanisms for multiple resistances in field populations of rice stem borer, Chilo suppressalis (Lepidoptera: Crambidae) from Sichuan Province, China.

Chilo suppressalis Walker (Lepidoptera: Crambidae) is a widely destructive pest occurring in rice, particularly in the rice-growing regions of Asia. In recent years, C. suppressalis has developed resistance to several insecticides because of the extensive use of insecticides. The resistance levels to four insecticides were determined among populations from different regions of Sichuan Province, China, using a drop-method bioassay. Based on LC50 values of a laboratory susceptible strain, all field populations showed moderate level of resistance to triazophos (23.9- to 83.5-fold) and were either susceptible or had a low level of resistance to abamectin (2.1- to 5.8-fold). All field-collected populations had a low or moderate level of resistance to chlorpyrifos (1.7- to 47.1-fold) and monosultap (2.7- to 13.5-fold). The synergism experiment indicated that the resistance of the XW19 to triazophos may be associated with cytochrome P450 monooxygenases (P450s), with the highest synergistic ratio (SR) of 3.05-fold and increased ratio (IR) of 2.28-fold for piperonylbutoxide (PBO). The P450 activity of the TJ19 population was the greatest among the six field populations. Moreover, the relative expression levels of four resistance-related P450 genes were detected with qRT-PCR, and the results indicated that CYP324A12, CYP321F3 and CYP9A68 were overexpressed in the resistant population, especially in the XW19 population (by 1.2-, 3.4 -, and 18.0-fold, respectively). In addition, the relative expression levels of CYP9A68 among the CZ19 and TJ19 populations were also enhanced 10.5- and 24.9-fold, respectively. These results suggested that CYP324A12, CYP321F3 and CYP9A68 may be related to the resistance development of C. suppressalis to triazophos.

[Clinical characteristics of pediatric hemorrhagic fever with renal syndrome].

OBJECTIVE: To study the clinical characteristics of pediatric hemorrhagic fever with renal syndrome (HFRS), and to improve its understanding so as to reduce the misdiagnosis. METHODS: A retrospective analysis was performed on the clinical data of 26 children with HFRS between January 2009 and December 2012. RESULTS: The age of disease onset was mainly distributed between 7 and 14 years (23 cases, 88%), and the male-to-female ratio was 1.89:l. The clinical manifestations of pediatric HFRS varied. The early symptoms resembled those of a cold, and in the course of HFRS, most patients developed digestive symptoms such as vomiting and abdominal pain. The laboratory examinations usually implicated platelet changes, and the imaging examinations revealed polyserous effusions. The prominent complication was myocardial injury. CONCLUSIONS: Pediatric HFRS mainly occurs in school-age children, more commonly in males. HFRS does not have typical clinical manifestations or symptoms, so it should be distinguished from cold or appendicitis at the early stage. When applying the fluid replacement therapy, the cardiac function should be carefully monitored in case of heart failure.

Accuracy of early detection of colorectal tumours by stool methylation markers: a meta-analysis.

AIM: To evaluate the accuracy of methylation of genes in stool samples for diagnosing colorectal tumours. METHODS: Electronic databases including PubMed, Web of Science, Chinese Journals Full-Text Database and Wanfang Journals Full-Text Database were searched to find relevant original articles about methylated genes to be used in diagnosing colorectal tumours. A quality assessment of diagnostic accuracy studies tool (QADAS) was used to evaluate the quality of the included articles, and the Meta-disc 1.4 and SPSS 13.0 software programs were used for data analysis. RESULTS: Thirty-seven articles met the inclusion criteria, and 4484 patients were included. The sensitivity and specificity for the detection of colorectal cancer (CRC) were 73% (95%CI: 71%-75%) and 92% (95%CI: 90%-93%), respectively. For adenoma, the sensitivity and specificity were 51% (95%CI: 47%-54%) and 92% (95%CI: 90%-93%), respectively. Pooled diagnostic performance of SFRP2 methylation for CRC provided the following results: the sensitivity was 79% (95%CI: 75%-82%), the specificity was 93% (95%CI: 90%-96%), the diagnostic OR was 47.57 (95%CI: 20.08-112.72), the area under the curve was 0.9565. Additionally, the results of accuracy of SFRP2 methylation for detecting colorectal adenomas were as follows: sensitivity was 43% (95%CI: 38%-49%), specificity was 94% (95%CI: 91%-97%), the diagnostic OR was 11.06 (95%CI: 5.77-21.18), and the area under the curve was 0.9563. CONCLUSION: Stool-based DNA testing may be useful for noninvasively diagnosing colorectal tumours and SFRP2 methylation is a promising marker that has great potential in early CRC diagnosis.

Detection of promoter hypermethylation of Wnt antagonist genes in fecal samples for diagnosis of early colorectal cancer.

AIM: To investigate the feasibility of detecting aberrantly hypermethylated Wnt-antagonist gene promoters (SFRP2 and WIF-1) in fecal DNA as non-invasive biomarkers for early colorectal cancer (CRC). METHODS: The methylation-specific polymerase chain reaction assay was performed to blindly analyze the methylation status of SFRP2 and WIF-1 gene promoters in fecal samples from 48 subjects with CRC, 35 with adenomas, 32 with hyperplastic polyps and 30 endoscopically normal subjects. Additionally, we compared the diagnostic efficiency of measuring the hypermethylated SFRP2 and WIF-1 genes in the feces to the fecal occult blood test (FOBT) for the early detection of CRC. RESULTS: Hypermethylated SFRP2 was detected in the feces of 56.3% (27/48) of CRC cases, 51.4% (18/35) of adenoma cases and 12.5% (4/32) of patients with hyperplastic polyps. The hypermethylation of WIF-1 was detected in 60.4% (29/48), 45.7% (16/35) and 18.7% (6/32) of fecal samples from CRC, adenoma and hyperplastic polyp patients, respectively. At least one hypermethylated gene was detected in 81.3% (39/48) of CRC and 65.7% (23/35) of adenoma samples. In contrast, only a hypermethylated WIF-1 gene was detected in one case of normal fecal samples. Moreover, no significant associations were observed between SFPR2 and WIF-1 hypermethylation and clinicopathological features. Additionally, 81.8% of CRC cases diagnosed as Dukes A stage or advanced adenomas had at least one hypermethylated gene detected, while the detection rate with the FOBT was only 31.8% (P < 0.001). CONCLUSION: Hypermethylated SFRP2 and WIF-1 genes in fecal DNA are novel and promising molecular biomarkers that have great diagnostic potential for early CRC.

[Research on the relation between ACE gene I/D polymorphisms and sensitivity to endurance training of Han nationality male].

AIM: In order to seek the marks of the genes, the relation between the influence of endurance training on aerobic ability and ACE Gene I/D Polymorphisms were studied. METHODS: 102 army recruits of Han nationality from North China for an 18 week en durance training of 5000m distance. Their VO2(max), VT and the left ventricular structure and function were measured before and after the training. We also tested their ACE Gene I/D Polymorphisms with PCR-AFLP method. RESULTS: The compliance of VO2(max), VT and left ventricular structure and function had improved after the training; the deltaVO2(max) of ID and II type was obviously higher than that of DD type (P < 0.05); there was obviously diference of deltaVO2(VT) in different ACE genotype (P < 0.05), the deltaVO2(VT) of type II was obviously higher than that of DD type (P < 0.05). CONCLUSION: I allele has obviously hereditary advantage on the sensitivity to aerobic training in VO2(max) and VT, and type II has relation on the sensitivity to aerobic training in VT; there is no relation between I/D polymorphism and the sensitivity to aerobic training on the structure and function of left ventricle.