A stratified genetic risk assessment for testicular cancer

Three genome-wide association studies of testicular cancer have uncovered predisposition alleles in or near KITLG, BAK1, SPRY4, TERT, ATF7IP and DMRT1. We investigated whether testicular cancer-risk alleles can be utilized in the clinical setting. We employed the receiver operating characteristic curves for genetic risk models to measure the discriminatory power of a risk variant-based risk model, and found that the newly discovered variants provided a discriminatory power of 69.2%. This suggested that about 69.2% of the time, a randomly selected patient with testicular cancer had a higher estimated risk than the risk for a randomly selected control subject. Using a multiplicative model, we estimated that white men in the top 1% of genetic risk as defined by eight risk variants had a relative risk that was 10.5-fold greater than that for the general white male population. This risk differential does not appear to be clinically useful, given the relative rarity and highly curable nature of testicular germ cell tumour (TGCT). In the authors' view, a stratified genetic risk assessment strategy might be useful, theoretically, for men who also have independent clinical risk factors for testicular cancer. Several established TGCT risk factors, such as cryptorchidism (RR=4.8) and male infertility (SIR=2.8) might prove useful in that context, but we currently do not know whether these testicular cancer-risk loci are associated with, or independent of, such clinical risk factors. More research is required before we can utilize testicular cancer-risk loci for clinically meaningful risk prediction.

High-speed optical humidity sensors based on chiral sculptured thin films

A high-speed humidity sensor based on a nanostructured chiral sculptured thin film (CSTF) was fabricated and tested. The sensing principle is based on the shift of the central wavelength of the circular Bragg regime of the CSTF caused by adsorption and desorption of water vapor in the void regions of the CSTF. Spectral changes due to varying relative-humidity (RH) levels in the ambient environment were measured by a spectrometer. The CSTF sensor exhibited excellent reversibility and reproducibility from 40% to 100% RH. Moreover, the adsorption time of the sensor was measured to be as low as ∼140 ms, making it promising for many high-speed humidity-sensing applications.

Three-dimensional continuous particle focusing in a microfluidic channel via standing surface acoustic waves (SSAW)

Three-dimensional (3D) continuous microparticle focusing has been achieved in a single-layer polydimethylsiloxane (PDMS) microfluidic channel using a standing surface acoustic wave (SSAW). The SSAW was generated by the interference of two identical surface acoustic waves (SAWs) created by two parallel interdigital transducers (IDTs) on a piezoelectric substrate with a microchannel precisely bonded between them. To understand the working principle of the SSAW-based 3D focusing and investigate the position of the focal point, we computed longitudinal waves, generated by the SAWs and radiated into the fluid media from opposite sides of the microchannel, and the resultant pressure and velocity fields due to the interference and reflection of the longitudinal waves. Simulation results predict the existence of a focusing point which is in good agreement with our experimental observations. Compared with other 3D focusing techniques, this method is non-invasive, robust, energy-efficient, easy to implement, and applicable to nearly all types of microparticles.

Evaluation ECMO in adult cardiac transplantation: can outcomes of marginal donor hearts be improved?

AIM

This study documents our experience with the use of ECMO in adult cardiac transplantation. Furthermore, in an attempt to improve outcomes of donor hearts with long ischemic times (LITs) we evaluated the efficacy of a strategy based on intraoperative ECMO (i-ECMO) circuit extended into postoperative cardiopulmonary support.

METHODS

From February 2005 to September 2009, 11 patients (i-ECMO group) receiving allografts with LITs >7 hours underwent intraoperative ECMO circuit strategy with routine extension of ECMO into postoperative period. Eleven contemporary patients (s-CPB group) received ECMO support after standard CPB at the various intervals after the transplantation as a salvage therapy.

RESULTS

Overall weaning rate was 86.4%; overall 30-day and 1-year survival rates were 81.8% and 72.7%, respectively. There was no difference in mortality between the two groups. Length of stay in the intensive care unit, the requirement for packed red blood cells administration and the total in-hospital cost were significantly reduced in i-ECMO group patients (P<0.05).

CONCLUSION

The salvage of failing cardiac allograft with ECMO allows effective stabilization of the hemodynamic and leads toward myocardial recovery. Extending ECMO into postoperative period provides early, continues and effective support for donor hearts with LITs and maximizes the use of such marginal organs.

Novel loci for major depression identified by genome-wide association study of Sequenced Treatment Alternatives to Relieve Depression and meta-analysis of three studies

We report a genome-wide association study (GWAS) of major depressive disorder (MDD) in 1221 cases from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study and 1636 screened controls. No genome-wide evidence for association was detected. We also carried out a meta-analysis of three European-ancestry MDD GWAS data sets: STAR*D, Genetics of Recurrent Early-onset Depression and the publicly available Genetic Association Information Network-MDD data set. These data sets, totaling 3957 cases and 3428 controls, were genotyped using four different platforms (Affymetrix 6.0, 5.0 and 500 K, and Perlegen). For each of 2.4 million HapMap II single-nucleotide polymorphisms (SNPs), using genotyped data where available and imputed data otherwise, single-SNP association tests were carried out in each sample with correction for ancestry-informative principal components. The strongest evidence for association in the meta-analysis was observed for intronic SNPs in ATP6V1B2 (P=6.78 x 10⁻⁷), SP4 (P=7.68 x 10⁻⁷) and GRM7 (P=1.11 x 10⁻⁶). Additional exploratory analyses were carried out for a narrower phenotype (recurrent MDD with onset before age 31, N=2191 cases), and separately for males and females. Several of the best findings were supported primarily by evidence from narrow cases or from either males or females. On the basis of previous biological evidence, we consider GRM7 a strong MDD candidate gene. Larger samples will be required to determine whether any common SNPs are significantly associated with MDD.

Effect of film thickness and filler properties on sulphuric acid permeation in various commercially available epoxy mortar coatings

The performance of various commercially available epoxy mortar coatings was compared by measuring their sulphuric acid diffusivity. Apparent diffusivities, which were measured gravimetrically, were found to be dependent on coating tortuosity. In composite materials like epoxy mortars, the tortuosity was determined by filler properties and polymer alignment. Tortuosity was found to depend on the filler size, their dispersion, filler aspect ratio and concentration. The order and greater alignment of polymer aggregates, which characterises thinner coatings effects higher tortuosity and thus lower permeabilities. The result is that sulphuric acid diffusivities were observed to increase with coating thickness, which challenges the notion that greater coating thicknesses provide greater protection or environmental barrier. The effect of film thickness and filler properties observed in this study has significant implications to the current selection of coatings and sewer protection.

Optofluidic microcavities: Dye-lasers and biosensors

Optofluidic microcavities are integrated elements of microfluidics that can be explored for a large variety of applications. In this review, we first introduce the physics basis of optical microcavities and microflow control. Then, we describe four types of optofluidic dye lasers developed so far based on both simple and advanced device fabrication technologies. To illustrate the application potential of such devices, we present two types of laser intracavity measurements for chemical solution and single cell analyses. In addition, the possibility of single molecule detection is discussed. All these recent achievements demonstrated the great importance of the topics in biology and several other disciplines.

Genome-wide association studies of pigmentation and skin cancer: a review and meta-analysis

Recent genome-wide association studies (GWAS) identified genetic loci associated with pigmentation, nevi, and skin cancer. We performed a review and meta-analysis of GWAS results, grouping them into four categories: (i) loci associated with pigmentation (hair, eye, and/or skin color), cutaneous UV-response (sun sensitivity and/or freckling), and skin cancer; (ii) loci associated with nevi and melanoma; (iii) loci associated with pigmentation and/or cutaneous UV-response but not skin cancer; and (iv) loci associated distinctly with skin cancer, mostly basal cell carcinoma, but not pigmentation or cutaneous UV-response. These findings suggest at least two pathways for melanoma development (via pigmentation and via nevi), and two pathways for basal cell carcinoma development (via pigmentation and independent of pigmentation). However, further work is necessary to separate the association with skin cancer from the association with pigmentation. As with any GWAS, the identified loci may not include the causal variants and may need confirmation by direct genome sequencing.

Protective effects of icariin on brain dysfunction induced by lipopolysaccharide in rats

In this study we examined the protective effects of icariin, a flavonol isolated from Herba epimedii, on learning and memory in a rat model with brain inflammation induced by lipopolysaccharide (LPS). Injecting LPS into the lateral ventricle caused rat brain dysfunction, as evidenced by deficits of spatial learning and memory in the Morris water maze. With administration of icariin (30, 60, 120mg/kg body wt./day) for 17 consecutive days, spatial learning and memory abilities were markedly altered. Escape latency and searching distance decreased, and the expressions of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and cyclooxygenase-2 (COX-2) of brain were significantly reduced as observed by real-time RT-PCR and immunohistochemistry. This study used ibuprofen (40mg/kg body wt./day) as positive control. In conclusion, this study suggested that icariin can improve spatial learning and memory abilities in rats with brain dysfunction induced by LPS, an effect which may be due to decreased expressions of TNF-α, IL-1β and COX-2 in the hippocampus.