A Monte Carlo simulation for studying grid inefficiency of Frisch grid ionization chamber.

The grid inefficiency (GI) of Frisch grid ionization chambers (FGICs) must be considered in the case of accurate energy measurements. A Monte-Carlo model has been developed based on the Garfield and SRIM toolkits to investigate the GI of FGIC. It could simulate the charge signals from different electrodes without considering the electrical noises and random effects in the experiments. Computations made with the weighting potential and charge signals of FGIC exemplify the possibilities of this model. The GI values obtained with different methods showed the difference among the existing approaches in the literature. In addition, the results of homogeneous deformations of one wire over one grid period showed that deformation in the grid plane caused more distortion on GI than that perpendicular to the grid plane. An individual experiment was also carried out with a compound alpha source (241Am and 243Am) to validate the feasibility of this model. The results showed that the raw pulses and GI values obtained from the simulation agreed well with those measured from the experiment. The present work showed that this Monte-Carlo model could be well applied to investigate such type of detector, which could provide great conveniences for future work to measure the total kinetic energy of the fission fragments.

Genotype distribution characteristics of multiple human papillomavirus in women from the Taihu River Basin, on the coast of eastern China.

BACKGROUND: There is limited data on the genotype distribution of human papillomavirus (HPV) in the Taihu River Basin, home to 1.29 million people on the coast of eastern China. This study evaluated the prevalence and genotypes among different female age groups in this region. METHODS: Twenty-six HPV strains (low-risk HPV 6, 11, 40, 42, 44, 61, 73 and high-risk HPV 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 55, 56, 58, 59, 66, 68, 82, and 83) were detected using Tellgenplex™ HPV technology in samples obtained from three clinical hospitals located in different regions of the Taihu Lake Basin. RESULTS: The results showed that 1855 samples (20.97% of all samples) were found to be HPV-positive. Of these, 1375 samples (15.55% of all samples) were found to have a single HPV infection. Age-specific prevalence showed two peaks, one that corresponded to the group of 21-30 year-old women and the other peak that corresponded to the group of women over 51 years old. The three most prevalent genotypes were HPV52 (19.95%, 370/1855), HPV16 (13.48%, 150/1855), and HPV58 (11.32%, 210/1855). Mixed strains HPV58 + HPV33 and HPV58 + HPV52 were most commonly found in females infected with multiple HPV types. CONCLUSIONS: This investigation reveals that HPV infection in the Taihu River Basin varied significantly among different age groups. The most prevalent genotypes are included in the nonavalent vaccine, V503, however this vaccine is not licensed for use in mainland China. The most frequently occurring genotypes should be considered in the development of next-generation HPV vaccines for optimal protection of public health.

Expression of microRNA-30c via lentivirus vector inhibits the proliferation and enhances the sensitivity of highly aggressive ccRCC Caki-1 cells to anticancer agents.

The clear cell renal cell carcinoma (ccRCC) is one of the most fatal urologic tumors, and the prognosis remains very poor for advanced or metastatic ccRCC. This study reveals the roles of microRNA (miR)-30c in regulating a highly aggressive ccRCC cell line proliferation by targeting MTA-1, which is a key mediator for human cancer metastasis. Results from quantitative real-time polymerase chain reaction showed that the expression of MTA-1, the target of miR-30c, was significantly higher in metastatic ccRCC specimens than in nonmetastatic ccRCC or nontumor specimens. Accordingly, endogenous miR-30c is at a much lower level in highly aggressive ccRCC Caki-1 cells than nontumor or ccRCC cell lines. Expression of miR-30c via lentivirus vector inhibits the proliferation, anchorage-independent growth, in vitro invasion or migration, or in vivo growth of Caki-1 cells by repressing MTA-1 protein expression. miR-30c also enhances the sensitivity of Caki-1 cells to anticancer agents, including sorafenib and paclitaxel. These data reveal the potential application of miR-30c and that its targeting gene, MTA-1, would be a potential target in metastatic ccRCC treatment.

Correlation between small dense low-density lipoprotein cholesterol and carotid artery intima-media thickness in a healthy Chinese population.

BACKGROUND: Small dense low-density lipoprotein cholesterol (sdLDL-C) concentration was useful in the assessment of the presence of cardiovascular diseases (CVD) and its severity. We examined whether SdLDL-C is more closely associated with carotid artery intima-media thickness (CA-IMT), a surrogate measure of atherosclerosis, than LDL-C and traditional CVD risk factors in Chinese healthy subjects. METHODS: We measured CA-IMT, blood pressure (BP), sdLDL-C, glucose metabolism and lipid in 183 native Chinese healthy subjects. CA-IMT was assessed by ultrasonography, and sdLDL-C concentrations were measured by a homogenous assay. Pearson's correlation coefficient analyses and Multiple regression analyses were used to examine the relationships between CA-IMT values and other clinical variables. RESULTS: The sdLDL-C level was significantly higher in males than in females (p <0.05) and there was an age effect on sdLDL-C (p <0.05). When the effects of age, gender and other traditional CVD risk factors were adjusted using multiple regression analysis. CA-IMT remained significantly associated with sdLDL-C(ß = 0.437, p <0.001). CONCLUSIONS: There are gender and age differences in sdLDL-C levels among a healthy Chinese population. Moreover, we found adjusted traditional CVD risk factors such as higher age, male sex, and other traditional CVD risk factors, the association between CA-IMT and SdLDL-C remained significant. sdLDL-C is may be a useful predictor in the assessment of CA-IMT in Chinese population.