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.

A self referencing platinum nanoparticle decorated enzyme-based microbiosensor for real time measurement of physiological glucose transport

Glucose is the central molecule in many biochemical pathways, and numerous approaches have been developed for fabricating micro biosensors designed to measure glucose concentration in/near cells and/or tissues. An inherent problem for microsensors used in physiological studies is a low signal-to-noise ratio, which is further complicated by concentration drift due to the metabolic activity of cells. A microsensor technique designed to filter extraneous electrical noise and provide direct quantification of active membrane transport is known as self-referencing. Self-referencing involves oscillation of a single microsensor via computer-controlled stepper motors within a stable gradient formed near cells/tissues (i.e., within the concentration boundary layer). The non-invasive technique provides direct measurement of trans-membrane (or trans-tissue) analyte flux. A glucose micro biosensor was fabricated using deposition of nanomaterials (platinum black, multiwalled carbon nanotubes, Nafion) and glucose oxidase on a platinum/iridium microelectrode. The highly sensitive/selective biosensor was used in the self-referencing modality for cell/tissue physiological transport studies. Detailed analysis of signal drift/noise filtering via phase sensitive detection (including a post-measurement analytical technique) are provided. Using this highly sensitive technique, physiological glucose uptake is demonstrated in a wide range of metabolic and pharmacological studies. Use of this technique is demonstrated for cancer cell physiology, bioenergetics, diabetes, and microbial biofilm physiology. This robust and versatile biosensor technique will provide much insight into biological transport in biomedical, environmental, and agricultural research applications.

Brain death disrupts structure and function of pig liver

OBJECTIVE

To observe the effects of brain death on hepatic structure and function in pigs and to assess the role of nuclear factor kappaB (NF-kappaB).

MATERIALS AND METHODS

Twelve healthy pigs were randomly allocated to 2 groups of 6 each: a control group with Foley balloon catheter placement intracalvarium only, and a group with brain death established for 24 hours. Serum and hepatic tissue were obtained at 6, 12, and 24 hours after initial confirmation of brain death. Aspartate aminotransferase and alanine aminotransferase concentrations were determined using automated biochemistry analysis. Interleukin-1beta was determined using an enzyme-linked immunosorbent assay. The NF-kappaB messenger RNA was determined using real-time polymerase chain reaction, and NF-kappaB p65 using immunohistochemistry.

RESULTS

Concentrations of aspartate aminotransferase, alanine aminotransferase, and interleukin-1beta in serum, and NF-kappaB messenger RNA and NF-kappaB p65 in hepatic tissue were higher in the brain-dead group compared with the control group, and all increased over time (P<.05).

CONCLUSION

The NF-kappaB activated by brain death promotes synthesis and release of inflammatory mediators, resulting in hepatic dysfunction.