Intermittent spike-wave dynamics in a heterogeneous, spatially extended neural mass model

Generalised epileptic seizures are frequently accompanied by sudden, reversible transitions from low amplitude, irregular background activity to high amplitude, regular spike-wave discharges (SWD) in the EEG. The underlying mechanisms responsible for SWD generation and for the apparently spontaneous transitions to SWD and back again are still not fully understood. Specifically, the role of spatial cortico-cortical interactions in ictogenesis is not well studied. We present a macroscopic, neural mass model of a cortical column which includes two distinct time scales of inhibition. This model can produce both an oscillatory background and a pathological SWD rhythm. We demonstrate that coupling two of these cortical columns can lead to a bistability between out-of-phase, low amplitude background dynamics and in-phase, high amplitude SWD activity. Stimuli can cause state-dependent transitions from background into SWD. In an extended local area of cortex, spatial heterogeneities in a model parameter can lead to spontaneous reversible transitions from a desynchronised background to synchronous SWD due to intermittency. The deterministic model is therefore capable of producing absence seizure-like events without any time dependent adjustment of model parameters. The emergence of such mechanisms due to spatial coupling demonstrates the importance of spatial interactions in modelling ictal dynamics, and in the study of ictogenesis.

Gender is an independent risk factor for distribution pattern and lesion morphology in chronic critical limb ischemia

The aim of this study was to determine gender differences in atherosclerotic lesion morphology and distribution pattern of patients with critical limb ischemia (CLI).

[Surgical therapy of gynecomastia]

Nowadays surgical intervention is an essential part of the treatment of idiopathic gynecomastia. Choosing the right method is crucial and is based on the current status in the clinical and histological evaluation. Before finalizing the process of choosing a specific method a prior interdisciplinary evaluation of the patient is necessary to ascertain clear indications for a surgical intervention. Liposuction is one of the methods which have become popular in recent years. The advantages are the possible combination with traditional techniques, such as subcutaneous mastectomy or periareolar mastopexy. The main indication is for gynecomastia stage IIa/b and is justifiable due to the reduction in surgical complications and scarring. Furthermore this technique provides an excellent aesthetical outcome for the patient. A total of 162 patients suffering from gynecomastia stages I-III (according to Simon) were surgically treated between 2000 and 2010 and these cases were retrospectively evaluated. The results showed a decline in the use of a T-shaped incision in combination with subcutaneous mastectomy with periareolar tightening compared to an increase in the use of subcutaneous mastectomy in combination with liposuction. The excised tissue should always be sent for histological examination to make sure no malignant cells were present.

Real-time quantitative broad-range PCR assay for detection of the 16S rRNA gene followed by sequencing for species identification

Here we determined the analytical sensitivities of broad-range real-time PCR-based assays employing one of three different genomic DNA extraction protocols in combination with one of three different primer pairs targeting the 16S rRNA gene to detect a panel of 22 bacterial species. DNA extraction protocol III, using lysozyme, lysostaphin, and proteinase K, followed by PCR with the primer pair Bak11W/Bak2, giving amplicons of 796 bp in length, showed the best overall sensitivity, detecting DNA of 82% of the strains investigated at concentrations of < or =10(2) CFU in water per reaction. DNA extraction protocols I and II, using less enzyme treatment, combined with other primer pairs giving shorter amplicons of 466 bp and 342 or 346 bp, respectively, were slightly more sensitive for the detection of gram-negative but less sensitive for the detection of gram-positive bacteria. The obstacle of detecting background DNA in blood samples spiked with bacteria was circumvented by introducing a broad-range hybridization probe, and this preserved the minimal detection limits observed in samples devoid of blood. Finally, sequencing of the amplicons generated using the primer pair Bak11W/Bak2 allowed species identification of the detected bacterial DNA. Thus, broad-spectrum PCR targeting the 16S rRNA gene in the quantitative real-time format can achieve an analytical sensitivity of 1 to 10 CFU per reaction in water, avoid detection of background DNA with the introduction of a broad-range probe, and generate amplicons that allow species identification of the detected bacterial DNA by sequencing. These prerequisites are important for its application to blood-containing patient samples.