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Open access

Wu Zhou, Lili Chen, Huijun Yu, Bei Peng and Yu Chen

Abstract

The abnormal phenomenon occurring in sensor calibration is an obstacle to product development but a useful guideline to product improvement. The sensitivity jump of micro accelerometers in the calibrating process is recognized as an important abnormal behavior and investigated in this paper. The characteristics of jumping output in the centrifuge test are theoretically and experimentally analyzed and their underlying mechanism is found to be related to the varied stiffness of supporting beam induced by the convex defect on it. The convex defect is normally formed by the lithography deviation and/or etching error and can result in a jumping stiffness of folded microbeams and further influence the sensitivity when a part of the bending beams is stopped from moving by two surfaces contacting. The jumping level depends on the location of convex and has nothing to do with the contacting properties of beam and defects. Then the location of defect is predicted by theoretical model and simulation and verified by the observation of micro structures under microscopy. The results indicate that the tested micro accelerometer has its defect on the beam with a distance of about 290μm from the border of proof mass block.

Open access

Di-jiong Wu, Yu-hong Zhou, Bao-dong Ye and Qing-hong Yu

Abstract

Bone marrow microvessel plays an important role in the onset and progression of hematologic diseases whose genesis is regulated by a variety of regulatory factors. Since abnormal angiogenesis has been found in a number of malignant and non-malignant hematologic diseases, microvessel density can be a valuable prognostic indicator, and also a stratifying factor in some of these diseases. In some cases, inhibiting or stimulating angiogenesis with certain treatments may be very important in improving therapeutic outcomes. However, mechanisms underlying these effects are yet to be further investigated.

Open access

Yu Qiao, Xiao-Ming Feng, Ze-Zhou Liu, Shuang-Shuang Wang, Yu-Jin Hao and Chun-Xiang You

Cloning and Expression Analysis of LeTIR1 in Tomato

The full-length cDNA of LeTIR1 gene was isolated from tomato with EST-based in silico cloning followed by RACE amplification. LeTIR1 contained an open reading frame (ORF) 1872 bp long, encoding 624 amino acid residues. The predicted protein LeTIR1 had one F-box motif and eleven leucine-rich repeats (LRRs), all of which are highly conserved in TIR1 proteins of other plant species. Phylogenetic analysis showed that the LeTIR1 protein shared high similarity with other known TIR1 proteins. Both sequence and phylogenetic analysis suggested that LeTIR1 is a TIR1 homologue and encodes an F-box protein in tomato. Semi-quantitative RT-PCR indicated that LeTIR1 was expressed constitutively in all organs tested, with higher expression in stem than root, leaf, flower and fruit. Its expression level was positively correlated with the auxin distribution in stem or axillary shoot, and was induced by spraying exogenous IAA.

Open access

Yaping Xu, Youhua Jiang, Xinmin Yu, Qixun Chen, Xinming Zhou and Weimin Mao

Abstract

Background. The 7th edition of the new TNM classification system for oesophageal cancer (EC) has been published. N-category is now divided into N0, N1, N2 and N3. In this study, we aimed to validate the prognostic ability of the new N classification system in EC with positive lymph nodes in a Chinese population, and evaluate whether the new N classification system can help the decision-making for postoperative adjuvant therapy.

Patients and methods. From 2002 to 2008, thoracic EC who underwent oesophagectomy were retrospectively analysed. Patients pathological stage 6th edition of the American Joint Committee on Cancer / Union International Against Cancer (AJCC/UICC) TNM classification were switched to pathological stage 7th edition for this analysis. Patients with pathological stage T1-4N1-3M0 EC were selected. Kaplan-Meier method and Cox regression analysis were employed to compare overall survival (OS).

Results. A total of 545 patients met the inclusion criteria: 346 (63.5%) received oesophagectomy alone, 199 (36.5%) received oesophagectomy and adjuvant radiotherapy, and 36.1% (197/545) received oesophagectomy and adjuvant chemotherapy. Univariate analysis and multivariate analysis revealed significant difference in OS among patients at different postoperative pN-category (p<0.001). This was also present in patients receiving postoperative radiotherapy (p<0.001) and those undergoing postoperative chemotherapy (p<0.001). There was no marked difference in OS between patients receiving postoperative adjuvant therapy and surgery alone at the same postoperative pN-category, except that postoperative radiotherapy marginally improved OS in patients with pN2 and pN3 disease.

Conclusions. Our results validated the prognostic ability of new N classification system. The N-category is an independent prognostic factor in patients with resectable thoracic EC who were positive for lymph nodes in a Chinese population. Further studies are required to clarify the role of new N classification system in the decision-making for postoperative adjuvant therapy.

Open access

Shu Wan, Hengjun Zhou, Jianbo Yu, Yuehui Ma, Jun Li and Renya Zhan

Abstract

Background: Malignant peripheral nerve sheath tumors (MPNST) are rare neoplasms, usually arising from peripheral nerves or showing a nerve sheath differentiation. Primary MPNSTs of the scalp is exceptionally rare, and only sporadic cases have been reported recently.

Objectives: Report a rare case of giant malignant peripheral nerve sheath tumor (MPNST) beneath occipital scalp, and discuss how to treat with this kind of tumor.

Methods: Descriptive study of a rare case of giant peripheral nerve sheath tumors of occipital scalp without adjuvant treatment with nine months follow up.

Results: In a 52-year-old man with MPNSTs beneath occipital scalp, the tumor was treated with complete surgical resection. Histological examination proved that the lesion was a scalp MPNST. The patient was followed up asymptomatic for the following nine months after surgical resection without adjuvant radiotherapy.

Conclusion: MPNSTs beneath the occipital scalp should be treated individually, for those well-circumscribed MPNSTs without bone destruction or brain invasion (low-grade tumors), complete surgical resection with clear margins (if possible) is recommended. Otherwise, adjuvant postoperative radiotherapy is necessary.

Open access

Qiu Jue Wu, Qin Yu Wang, Tian Wang and Yan Min Zhou

Abstract

The effects of natural clinoptilolite (NCLI) and modified clinoptilolite (MCLI) were evaluated in broilers challenged with lipopolysaccharide (LPS) in a 21-d feeding trial. A total of 288 one-day-old chickens were allocated into three treatment groups: control, NCLI (2%) and MCLI (2%). Half of the birds from each treatment group were challenged with either 0.9% NaCl solution or LPS (250 μg/kg body weight, orally administered) at 16, 18 and 21 d of age. Before the LPS challenge, no dietary effect on bird growth performance was found (P>0.05). When LPS was orally administered, no significant changes in growth performance of broilers was found (P>0.05). However, small intestinal morphology and development, malondialdehyde (MDA) content of the jejunual and ileal mucosa, and superoxide dismutase (SOD) activity of the ileal mucosa were significantly affected (P<0.05). Supplementation with NCLI and MCLI significantly decreased the MDA contents of the jejunual and ileal mucosa and improved the SOD activity of the ileal mucosa and the development of the small intestine compared with the control group (P<0.05). The results indicated that NCLI and MCLI additions in feed had protective effects on the gut health of broilers against LPS challenge.

Open access

Qin Zhou, Yu-feng Gao, Xiao-miao Zhao, Fa-ming Pan and Xu Li

Abstract

Objective To investigate the relationship between single nucleotide polymorphisms (SNPs) of the interleukin-4 (IL-4) gene and outcome of hepatitis B virus (HBV) infection in a Chinese Han population.

Methods Total of 501 patients with chronic hepatitis B virus (HBV) infection and 301 controls with selflimiting HBV infection were studied. Three tag SNPs in the IL-4 gene (rs2227284G/T, rs2243283C/G and rs2243288A/G) were genotyped by the Multiplex snapshot technique. The genotype and allele frequencies were calculated and analyzed.

Results The three SNPs showed no significant genotype/allele associations with chronic HBV infection. Overall allele P values were: rs2227284, P = 0.655, odds ratio (OR) [95% confidence interval (CI)] = 1.070 (0.793-1.445); rs2243283, P = 0.849, OR (95% CI) = 0.976 (0.758-1.257); rs2243288, P = 0.659, OR (95% CI) = 1.060 (0.818-1.375). Overall genotype P values were: rs2227284, P = 0.771; rs2243283, P = 0.571; rs2243288, P = 0.902. There were no statistically significant differences between patients with chronic HBV infection and controls. Haplotypes generated by these three SNPs also had no significant differences between the two groups.

Conclusions The three tag SNPs of IL-4 were not associated with the outcome of HBV infection in the Han Chinese population.

Open access

Jian-Ping Yu, Wen Wang, Xin Li and Zhao-Zhong Zhou

Abstract

This paper presents a novel phase-shift arctangent (PSA) interpolation method to improve the measurement accuracy of a planar capacitive incremental displacement sensor. Signals of planar capacitive micro-sensors acquire waveform errors, including sensitivity differences and phase-shift errors, because of static errors and dynamic disturbances. In the proposed PSA scheme, such errors are removed completely by loading a particular arctangent function. Moreover, measuring efficiency of the proposed planar capacitive sensors is improved by combining coarse measurement and fine estimation. Experiments show unanimous results to model-based fitting. When electrode length is four times the gap distance, applying the PSA interpolation method decreases waveform errors from more than 4 % to 1.72 %.

Open access

Zhang Zhi-yong, Li Ming-xu, Yu Yong-wu and Zhou Chun-hua

Abstract

Background: At present, patients with end-stage renal failure (ESRD) face the question of how to achieve adequate dialysis to maintain their survival with the best quality of life as long as possible. Therefore, the choice of suitable dialysis methods and dialysis dose is important.

Objective: To find suitable dialysis methods and an appropriate dialysis dose for patients with ESRD.

Methods: Our research compares the long-term clinical effects between the patients undergoing continuous ambulatory peritoneal dialysis (CAPD), daytime ambulatory peritoneal dialysis (DAPD), and hemodialysis (HD). Thirty-two patients subjected to peritoneal dialysis were selected and divided into group A (n = 16) and group B (n = 16), group A was treated by using the traditional CAPD pattern; group B was treated by using DAPD. Forty-six patients of renal failure at final stage were divided into group A (n = 23) and group B (n = 23), group A was treated by using a HD method, group B was treated by using a DAPD method.

Results: When the same dialysis dose was applied, the patients with long-term DAPD treatment can obtain satisfactory clinical therapeutic efficacy for the period of maintenance dialysis, thoroughness of dialysis, maintenance of nutritional status, blood pressure regulation, reduction in incidence rate of peritoneal infection, maintenance of relatively high activity in daily life and alleviation in depression, comparable to patients treated with traditional CAPD or HD methods.

Conclusion: The long-term clinical effects of DAPD are comparable to CAPD or HD.

Open access

Wei Dai, Rong Zhou, Hong Yu and Xiao-juan Li

Abstract

Objective To develop an effective and specific medicine targeting hepatitis B virus (HBV) pregenome. Based on the identified accessible target sites for hammerhead ribozyme in our previous researches, a recombinant hepatitis delta virus (HDV) ribozyme was chosen and used to demonstrate the effective cleavage in vitro and in vivo.

Methods Three hammerhead ribozymes for potential target sites (S, X and C genes) and co-expression plasmid (pTr-dB, pTdδ-dB, pTrX-dB and pTrC-dB) as well as four HDV-ribozyme chimera constructs with HBV (pTdXX, pTdXC, pTdSX and pTdSC) were severally chosen to validate the inhibition of the replication and expression of HBV. The co-expression plasmids (pTdδ and pTr-Db) in physiological saline were hydrodynamically injected to mice by tail vein.

Results Compared with the group injected with pTr-dB in Huh-7 cell, hepatitis B surface antigen (HBsAg) was reduced by 31% in the group injected with pTdδ-dB, by 54%, 26%, 72% and 97% in the group injected with recombinant-ribozymes pTdSX, pTdSC, pTdXC and pTdXX, respectively. The inhibiting effects of endogenous ribozymes RzX and RzC on the HBsAg expression were 66% and 57%, respectively. Compared with the positive control, the amount of HBsAg was decreased in mice injected with pTdXX through tail vein by 88% and 96% on the second day and the third day, respectively. HBsAg was undetectable on the 6th day and could not primitively be detected on the 9th day in the sera from all mice. HBV DNA was not detected in the sera of BALB/c mice injected with pTdXX-dB, pTrX-dB or replicating-defective plasmid pHBV, while HBV DNA replication in control group could be detected on the 6th day. While HBcAg could not be detected in liver tissues of mice injected with plasmid pTdXX-dB on the 3rd day.

Conclusions Encoding regions of HBV S, C and X gene were the effective cleavage sites for hammerhead ribozyme in vitro and in vivo, which provides basis for further construction of therapeutic recombinant HDV and the development of targeting antiviral gene therapy.