Laser-induced vapor nanobubbles improve diffusion in biofilms of antimicrobial agents for wound care.

Being responsible for delayed wound healing, the presence of biofilms in infected wounds leads to chronic, and difficult to treat infections. One of the reasons why antimicrobial treatment often fails to cure biofilm infections is the reduced penetration rate of antibiotics through dense biofilms. Strategies that have the ability to somehow interfere with the integrity of biofilms and allowing a better penetration of drugs are highly sought after. A promising new approach is the use of laser-induced vapor nanobubbles (VNB), of which it was recently demonstrated that it can substantially enhance the penetration of antibiotics into biofilms, resulting in a marked improvement of the killing efficiency. In this study, we examined if treatment of biofilms with laser-induced vapor nanobubbles (VNB) can enhance the potency of antimicrobials which are commonly used to treat wound infections, including povidone-iodine, chlorhexidine, benzalkonium chloride, cetrimonium bromide and mupirocin. Our investigations were performed on Pseudomonas aeruginosa and Staphylococcus aureus biofilms, which are often implicated in chronic wound infections. Pre-treatment of biofilms with laser-induced VNB did enhance the killing efficiency of those antimicrobials which experience a diffusion barrier in the biofilms, while this was not the case for those compounds for which there is no diffusion barrier. The magnitude of the enhanced potency was in most cases similar to the enhancement that was obtained when the biofilms were completely disrupted by vortexing and sonication. These results show that laser-induced VNB are indeed a very efficient way to enhance drug penetration deep into biofilms, and pave the way towards clinical translation of this novel approach for treatment of wound infections.

CARDIAC AMYLOIDOSIS DIAGNOSED ON MRI.

The frequency of cardiac involvement varies among other types of amyloidosis. Cardiac amyloidosis leads to systolic and diastolic dysfunction with symptoms of heart failure. Cardiac magnetic resonance (CMR) findings are helpful in supporting the diagnosis of amyloid cardiomyopathy. We report a case of a 73-year-old man who presented with shortness of breath. Echocardiography showed a hypertrophic, diffusely hypocontractile left ventricle with a restrictive filling pattern. The diagnosis of an isolated amyloidosis was made on CMR.

Dilated cardiomyopathy caused by a novel TNNT2 mutation-added value of genetic testing in the correct identification of affected subjects.

Diagnosing familial dilated cardiomyopathy requires careful family history taking and clinical evaluation in first degree relatives. Based on the results of these findings the diagnosis may be established in the proband. However, due to the age-dependent expression of the disease, doubt may persist regarding the exact status of other family members, especially in young individuals. Here we present a family with DCM in whom we identified an underlying cardiac troponin T (TNNT2) mutation. Genetic testing was essential for the detection of asymptomatic carriers as well as for exclusion of the disease in other family members.

Influence of GABA on the spectral and spatial coding of goldfish retinal ganglion cells.

The responses of center red ON and center red OFF ganglion cells of the isolated goldfish retina to a flickering stimulus light diminish by GABA. Without stimulation GABA blocks the maintained activity of the OFF cells. With a green flickering spot in the receptive field center, the green ON-response of the OFF cells becomes an OFF-response during GABA administration. It is concluded that, besides the common antagonistic green input, the receptive field center of these cells also has a synergistic green input, which is mediated by a pathway other than the center opponent red and green inputs.