Effects of Cyclic Strain and Growth Factors on Vascular Smooth Muscle Cell Responses

Under physiological and pathological conditions, vascular smooth muscle cells (SMC) are exposed to different biochemical factors and biomechanical forces. Previous studies pertaining to SMC responses have not investigated the effects of both factors on SMCs. Thus, in our research we investigated the combined effects of growth factors like Bfgf (basic fibroblast growth factor), TGF-β (transforming growth factor β) and PDGF (platelet-derived growth factor) along with physiological cyclic strain on SMC responses. Physiological cyclic strain (10% strain) significantly reduced SMC proliferation compared to static controls while addition of growth factors bFGF, TGF-β or PDGF-AB had a positive influence on SMC growth compared to strain alone. Microarray analysis of SMCs exposed to these growth factors and cyclic strain showed that several bioactive genes (vascular endothelial growth factor, epidermal growth factor receptor, etc.) were altered upon exposure. Further work involving biochemical and pathological cyclic strain stimulation will help us better understand the role of cyclic strain and growth factors in vascular functions and development of vascular disorders

Effects of Acute Cytomegalovirus Infection on Rat Islet Allograft Survival

Transplantation of pancreatic islets is a promising therapy for the treatment of type 1 diabetes mellitus. However, long-term islet graft survival rates are still unsatisfactory low. In this study we investigated the role of cytomegalovirus (CMV) in islet allograft failure. STZ-diabetic rats received an allogenic islet graft in combination with either an acute CMV infection or control infection. A third group received ganciclovir treatment in addition to the CMV infection. Graft function was assessed by measuring basal blood glucose levels. After sacrifice, the islet grafts were retrieved for analysis of infection and leukocyte infiltration. CMV-infected recipients demonstrated accelerated islet graft failure compared to noninfected controls. CMV infection of the graft was only observed prior to complete graft failure. Quantification of the leukocyte infiltration demonstrated increased CD8(+) T-cell and NK cell infiltration in the CMV-infected grafts compared to the controls. This suggests that CMV infection accelerates immune-mediated graft destruction. Antiviral ganciclovir treatment did not prevent accelerated graft failure, despite effectively decreasing the grade of infection. Our data confirm the recently published CITR data, which state that CMV is an independent risk factor for failure of islet grafts. Also, our data demonstrate that new approaches for preventing virus-induced islet allograft failure may be required

Perceptual Issues in Music Pattern Recognition: Complexity of Rhythm and Key Finding

We consider several perceptual issues in the context of machine recognition of music patterns. It is argued that a successful implementation of a music recognition system must incorporate perceptual information and error criteria. We discuss several measures of rhythm complexity which are used for determining relative weights of pitch and rhythm errors. Then, a new method for determining a localized tonal context is proposed. This method is based on empirically derived key distances. The generated key assignments are then used to construct the perceptual pitch error criterion which is based on note relatedness ratings obtained from experiments with human listeners

Worldwide experience of adult patients with small body size supported by a continuous-flow left ventricular assist device-an IMACS analysis

Purpose: The use of continuous-flow left ventricular assist devices (CF-LVADs) in adult patients with small body size is increasing worldwide. Our purpose is to compare the characteristics, adverse events (AE) and survival outcomes of patients with body surface area (BSA) \u3c 1.5 m2 (small) to ≥ 1.5 m2 (big) implanted with a CF-LVAD in a large international registry. Methods: The ISHLT Mechanically Assisted Circulatory Support (IMACS) Registry of all adult patients (≥ 18 years of age) who had a CF-LVAD from 1/2013-12/2016 (n= 13038) was examined: 396/13038 (3.1%) had BSA \u3c 1.5 m2 (median 1.36±0.12 m2) vs. n= 12499/13038 (96.9%) had BSA ≥ 1.5 m2 (median 2.05±0.29 m2). Results: Compared to larger patients, small BSA patients were more commonly younger (19-29 yrs. of age) [37/396 (9.3%)] vs. [559/12499 (4.5%); p\u3c 0.0001] and female [217/396 (54.8%) vs. 2429/12499 (19.5%); p\u3c 0.0001]. There was no difference in centrifugal vs. axial flow pumps implanted (p= 0.13) or Intermacs profile at implant (p= ns) in small vs. big patients. Small patients had more bleeding early (\u3c 3 mo. post implant; p= 0.02) and late (p= 0.03) along with a higher rate of late infection and late neurological dysfunction (Table) than big patients. There were no differences in early (p= 0.27) or late (p= 0.18) device malfunction and no differences in post implant survival (p= 0.65). Conclusion: There are important demographic differences and AE profiles in small vs. big patients implanted with CF-LVADs with comparable post implant survival. This data support the use of CF-LVAD in properly selected small adult patients at experienced centers worldwide (Table presented)

Differential regulation of somatostatin receptor types 1-5 in rat aorta after angioplasty

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