The relationship between individual alpha peak frequency and clinical outcome with repetitive Transcranial Magnetic Stimulation (rTMS) treatment of Major Depressive Disorder (MDD).

BACKGROUND: The individual α frequency (IAF) has been associated with the outcome of repetitive Transcranial Magnetic Stimulation (rTMS) treatment of Major Depressive Disorder (MDD), but the association has been inconsistent. HYPOTHESIS: Proximity of IAF to the stimulation frequency, rather than the value of IAF per se, is associated with outcome for patients receiving 10 Hz rTMS. METHODS: We examined the relationships between IAF, rTMS stimulation frequency, and treatment outcome in 147 patients. All patients initially received 10 Hz rTMS unilateral treatment delivered to left dorsolateral prefrontal cortex (DLPFC) (10UL), with subsets of patients changed to unilateral 5 Hz to left DLPFC (5UL) or sequential bilateral (SB) stimulation (10 Hz/1Hz) to left and right DLPFC based upon worsening symptoms with or intolerance of 10UL. Outcome was percent change in total score on the Inventory of Depressive Symptomatology - Self Report (IDS-SR) scale from pre-treatment baseline to the 30th treatment. IAF values and absolute difference between IAF and 10 Hz (|IAF-10Hz|) were examined in relation to outcome for the overall sample and for each stimulation group separately. RESULTS: There was no correlation between IAF value, or |IAF-10Hz| and outcome in the overall sample. ANCOVA showed a significant interaction between IAF measures and treatment type. Post-hoc analyses revealed that IAF and |IAF-10Hz| were both significantly associated with degree of improvement (IDS-SR % change) for patients who received 10UL (P < 0.01) but not 5UL or SB stimulation. There was a trend-level difference in IAF between responders and non-responders only within the 10 Hz group, but not within the other treatment groups (n.s.). For the 10UL group, membership in the highest IAF quartile was associated with significantly greater clinical improvement than membership in the lowest IAF quartile (p = 0.0034). CONCLUSIONS: IAF measures were associated with clinical outcome of patients treated with 10UL but not 5UL or SB rTMS treatment. This suggests that interactions between endogenous frequencies and treatment outcome may be related to the selected stimulation parameters and/or physiologic and clinical characteristics of patients who benefit from those parameters.

Building new hearts: a review of trends in cardiac tissue engineering.

Cardiovascular disease (CVD) is the number one cause of death in the United States. However, few treatments for CVD provide a means to regain full cardiac function with no long-term side effects. Novel tissue-engineered products may provide a way to overcome the limitations of current CVD therapies by replacing injured myocardium with functioning tissue or by inducing more constructive forms of endogenous repair. In this review, we discuss some of the factors that should be considered in the development of tissue-engineered products, and we review the methods currently being investigated to generate more effective heart valves, cardiac patches and whole hearts.

Covalently grafted VEGF(165) in hydrogel models upregulates the cellular pathways associated with angiogenesis.

Angiogenesis is an important biological response known to be involved in many physiological and pathophysiological situations. Cellular responses involved in the formation of new blood vessels, such as increases in endothelial cell proliferation, cell migration, and the survival of apoptosis-inducing events, have been associated with vascular endothelial growth factor isoform 165 (VEGF(165)). Current research in the areas of bioengineering and biomedical science has focused on developing polyethylene glycol (PEG)-based systems capable of initiating and sustaining angiogenesis in vitro. However, a thorough understanding of how endothelial cells respond at the molecular level to VEGF(165) incorporated into these systems has not yet been established in the literature. The goal of the current study was to compare the upregulation of key intracellular proteins involved in angiogenesis in human umbilical vein endothelial cells (HUVEC) and human microvascular endothelial cells (HMEC) seeded on PEG hydrogels containing grafted VEGF(165) and adhesion peptides Arg-Gly-Asp-Ser (RGDS). Our data suggest that the covalent incorporation of VEGF(165) into PEG hydrogels encourages the upregulation of signaling proteins responsible for increases in endothelial cell proliferation, cell migration, and the survival after apoptosis-inducing events.

Intimal hyperplasia and wall shear in arterial bypass graft distal anastomoses: an in vivo model study.

The observation of intimal hyperplasia at bypass graft anastomoses has suggested a potential interaction between local hemodynamics and vascular wall response. Wall shear has been particularly implicated because of its known effects upon the endothelium of normal vessels and, thus, was examined as to its possible role in the development of intimal hyperplasia in arterial bypass graft distal anastomoses. Tapered (4-7 mm I.D.) e-PTFE synthetic grafts 6 cm long were placed as bilateral carotid artery bypasses in six adult, mongrel dogs weighing between 25 and 30 kg with distal anastomotic graft-to-artery diameter ratios (DR) of either 1.0 or 1.5. Immediately following implantation, simultaneous axial velocity measurements were made in the toe and artery floor regions in the plane of the anastomosis at radial increments of 0.35 mm, 0.70 mm, and 1.05 mm using a specially designed 20 MHz triple crystal ultrasonic wall shear rate transducer Mean, peak, and pulse amplitude wall shear rates (WSRs), their absolute values, the spatial and temporal wall shear stress gradients (WSSG), and the oscillatory shear index (OSI) were computed from these velocity measurements. All grafts were harvested after 12 weeks implantation and measurements of the degree of intimal hyperplasia (IH) were made along the toe region and the artery floor of the host artery in 1 mm increments. While some IH occurred along the toe region (8.35+/-23.1 microm) and was significantly different between DR groups (p<0.003), the greatest amount occurred along the artery floor (81.6+/-106.5 microm, mean +/- S.D.) (p < 0.001) although no significant differences were found between DR groups. Linear regressions were performed on the paired IH and mean, peak, and pulse amplitude WSR data as well as the absolute mean, peak, and pulse amplitude WSR data from all grafts. The mean and absolute mean WSRs showed a modest correlation with IH (r = -0.406 and -0.370, respectively) with further improvements seen (r = -0.482 and -0.445, respectively) when using an exponential relationship. The overall best correlation was seen against an exponential function of the OSI (r = 0.600). Although these correlation coefficients were not high, they were found to be statistically significant as evidenced by the large F-statistic obtained. Finally, it was observed that over 75 percent of the IH occurred at or below a mean WSR value of 100 s(-1) while approximately 92 percent of the IH occurred at or below a mean WSR equal to one-half that of the native artery. Therefore, while not being the only factor involved, wall shear (and in particular, oscillators wall shear) appears to provide a stimulus for the development of anastomotic intimal hyperplasia.

Smooth muscle cell growth in photopolymerized hydrogels with cell adhesive and proteolytically degradable domains: synthetic ECM analogs for tissue engineering.

Photopolymerizable polyethylene glycol (PEG) derivatives have been investigated as hydrogel tissue engineering scaffolds. These materials have been modified with bioactive peptides in order to create materials that mimic some of the properties of the natural extracellular matrix (ECM). The PEG derivatives with proteolytically degradable peptides in their backbone have been used to form hydrogels that are degraded by enzymes involved in cell migration, such as collagenase and elastase. Cell adhesive peptides, such as the peptide RGD, have been grafted into photopolymerized hydrogels to achieve biospecific cell adhesion. Cells seeded homogeneously in the hydrogels during photopolymerization remain viable, proliferate, and produce ECM proteins. Cells can also migrate through hydrogels that contain both proteolytically degradable and cell adhesive peptides. The biological activities of these materials can be tailored to meet the requirements of a given tissue engineering application by creating a mixture of various bioactive PEG derivatives prior to photopolymerization.

[Mendelism in animal breeding as developed by professor Leopold Frateur, Louvain (1877-1946)]. / Leopold Frateur en het Mendelisme bij het fokken van huisdieren.

Educated as a veterinarian at Cureghem, Leopold Frateur started his scientific career in 1899 as a professor at the Faculty of Sciences of the Catholic University of Louvain, Belgium, in charge of the course in zootechnology. After a study tour to zootechnical institutes and centres of animal breeding in Europe he was invited by the governmental department of Agriculture and the Belgian Society of Zootechnology to investigate the relevance of the Mendelian laws of heredity for the improvement of cattle breeding. In the early years of the century, Frateur conducted field research in order to determine the characteristics of the cattle breeds in Belgium. In 1908 Frateur founded the Institute of Animal Husbandry at his university. Here he worked out his programme of experimental genetics until his retirement in 1936. The last six years of his professorship he teached also agricultural economics in the Faculty of Economical Sciences. In Frateur's experimental research the following main lines can be distinguished: 1) The analysis of simple and complex hereditary factors in cattle, rabbits and poultry; 2) The study of qualitative and quantitative characteristics of importance for the improvement of animal breeds; 3) The synthesis of genetic factors from different stock in order to obtain higher yielding breeds with stable characteristics; 4) Theoretical study of the relationship between genotype and phenotype and the influence of environment factors; 5) Theoretical exploration of the issue of variability and modification of newly formed characteristics; 6) Research leading to an explanation of telegony and atavism; 7) The formulation of a theory on the creation of new breeds in domestic animals and plants, and the relation between breed and species. Also he was responding to topical needs, e.g. he determined the causal factor of pullorum epidemic in chicken farming, or he investigated the hereditary resistance against diphteric infection amongst chickens. Frateur took the theoretical knowledge on heredity as the starting point for practical application in cattle breeding. During and right after W. W. I. he stated that the current scientific knowledge is enough advanced to consider the start of a large breeding programme for the improvement of cattle livestock. In order to realise this reinstatement Frateur received important support from the authorities (Royal Decree, August 1919). From then onwards he focussed his efforts on the realisation of a national framework for improvement of cattle livestock, in collaboration with regional centres and societies for animal selection, breeding and production. Later he also started programmes for the improvement of chicken and pig breeding, again in a joint effort with official consultants and members of breeding societies. He was not only the architect of these programmes, providing the necessary scientific and technical guidance, but he had also a chair in the governing bodies, supervising the execution and control of the breeding programmes. In order to draw a picture of the research community engaged in animal breeding during the first decennia of the 20th century Frateur's contacts through study tours, congresses and learned societies are investigated. The life and work of Frateur is described by the author in two volumes, published in 1999. The second volume consists of a reprint of 50 selected papers on animal breeding.