Staged Concept for Treatment of Severe Postsaphenectomy Wound Infection

The saphenous vein remains the most commonly used conduit in coronary artery bypass surgery. Vein harvest is a critical component with significant morbidity associated with leg wounds from open technique. Occurring complications are hematoma, postoperative pain, skin changes, neuropathy, and septic or nonseptic wound complications. Within the context of a recent case, we present our approach to postsaphenectomy wound management

Genetic parameters for Kleiber ratio and its relation to other body weight traits in Nilagiri and Sandyno sheep

Kleiber ratio (KR) is an indicator of growth efficiency irrespective of body size. The trait was recommended as an efficient indirect selection criterion. The present study was done to estimate genetic parameters for KR and explore the possibility of its use as a selection criterion in Nilagiri and Sandyno sheep. KR for the pre-weaning (birth to 3-months) and post-weaning (3– 6, 6–9, 9–12 and 3–12 months) periods was studied. Pre-weaning KR was much higher than post-weaning KR in both the breeds. The mean pre-weaning KR for Nilagiri and Sandyno sheep was 14.37 and 14.52, respectively. All the post-weaning KR values were less than six. Animal model including or ignoring maternal effects was used to obtain REML estimates of (co)variances. The best model was chosen based on log-likelihood ratio test. Maternal effects and inbreeding were not significant for KR at any of the age intervals. Moderate estimates of heritability were obtained for pre-weaning KR in both the breeds. Among the post-weaning KR, the age interval from 3–6 months and 3–12 months showed moderate values in Nilagiri sheep. Post-weaning KR for Sandyno sheep showed negligible to low heritability estimates. The maximum heritability of 0.143 was for KR 3–6 months in Nilagiri sheep. In Nilagiri sheep, genetic correlation between pre-weaning KR and body weight traits ranged from 0.634 to 0.875. Similarly, in Sandyno sheep, the values ranged from 0.883 to 0.959. Thus pre-weaning KR could be used as a criterion for indirect selection to improve important body weight traits

On Dark Matter Annihilation in the Local Group

Under the hypothesis of a Dark Matter composed by supersymmetric particles like neutralinos, we investigate the possibility that their annihilation in the haloes of nearby galaxies could produce detectable fluxes of $\gamma$-photons. Expected fluxes depend on several, poorly known quantities such as the density profiles of Dark Matter haloes, the existence and prominence of central density cusps and the presence of a population of sub-haloes. We find that, for all reasonable choices of Dark Matter halo models, the intensity of the $\gamma$-ray flux from some of the nearest extragalactic objects, like M31, is comparable or higher than the diffuse Galactic foreground. We show that next generation ground-based experiments could have the sensitivity to reveal such fluxes which could help us unveiling the nature of Dark Matter particles.Comment: 11 pages, 10 figures. Accepted for publication in Phys. Rev. D.; added a new paragraph on the detectability of Galactic sub-halos in our Galaxy; added a discussion on their model dependence. The relation of our results with the "CDM crisis" issue has also been adde

Origin and Propagation of Extremely High Energy Cosmic Rays

Cosmic ray particles with energies in excess of 10**(20) eV have been detected. The sources as well as the physical mechanism(s) responsible for endowing cosmic ray particles with such enormous energies are unknown. This report gives a review of the physics and astrophysics associated with the questions of origin and propagation of these Extremely High Energy (EHE) cosmic rays in the Universe. After a brief review of the observed cosmic rays in general and their possible sources and acceleration mechanisms, a detailed discussion is given of possible "top-down" (non-acceleration) scenarios of origin of EHE cosmic rays through decay of sufficiently massive particles originating from processes in the early Universe. The massive particles can come from collapse and/or annihilation of cosmic topological defects (such as monopoles, cosmic strings, etc.) associated with Grand Unified Theories or they could be some long-lived metastable supermassive relic particles that were created in the early Universe and are decaying in the current epoch. The highest energy end of the cosmic ray spectrum can thus be used as a probe of new fundamental physics beyond Standard Model. We discuss the role of existing and proposed cosmic ray, gamma-ray and neutrino experiments in this context. We also discuss how observations with next generation experiments of images and spectra of EHE cosmic ray sources can be used to obtain new information on Galactic and extragalactic magnetic fields and possibly their origin.Comment: 148 latex pages in tight format, 30 postscript-files and two gif-files for fig4.14 and fig4.15 included, uses epsf.sty. Considerably updated version of review to appear in Physics Reports. Links and color ps version of fig4.14 and fig4.15 at http://astro.uchicago.edu/home/web/sigl/physrep.htm

“Topological Significance” Analysis of Gene Expression and Proteomic Profiles from Prostate Cancer Cells Reveals Key Mechanisms of Androgen Response

The problem of prostate cancer progression to androgen independence has been extensively studied. Several studies systematically analyzed gene expression profiles in the context of biological networks and pathways, uncovering novel aspects of prostate cancer. Despite significant research efforts, the mechanisms underlying tumor progression are poorly understood. We applied a novel approach to reconstruct system-wide molecular events following stimulation of LNCaP prostate cancer cells with synthetic androgen and to identify potential mechanisms of androgen-independent progression of prostate cancer.We have performed concurrent measurements of gene expression and protein levels following the treatment using microarrays and iTRAQ proteomics. Sets of up-regulated genes and proteins were analyzed using our novel concept of "topological significance". This method combines high-throughput molecular data with the global network of protein interactions to identify nodes which occupy significant network positions with respect to differentially expressed genes or proteins. Our analysis identified the network of growth factor regulation of cell cycle as the main response module for androgen treatment in LNCap cells. We show that the majority of signaling nodes in this network occupy significant positions with respect to the observed gene expression and proteomic profiles elicited by androgen stimulus. Our results further indicate that growth factor signaling probably represents a "second phase" response, not directly dependent on the initial androgen stimulus.We conclude that in prostate cancer cells the proliferative signals are likely to be transmitted from multiple growth factor receptors by a multitude of signaling pathways converging on several key regulators of cell proliferation such as c-Myc, Cyclin D and CREB1. Moreover, these pathways are not isolated but constitute an interconnected network module containing many alternative routes from inputs to outputs. If the whole network is involved, a precisely formulated combination therapy may be required to fight the tumor growth effectively

Function-Based Discovery of Significant Transcriptional Temporal Patterns in Insulin Stimulated Muscle Cells

Background: Insulin action on protein synthesis (translation of transcripts) and post-translational modifications, especially of those involving the reversible modifications such as phosphorylation of various signaling proteins, are extensively studied but insulin effect on transcription of genes, especially of transcriptional temporal patterns remains to be fully defined. Methodology/Principal Findings: To identify significant transcriptional temporal patterns we utilized primary differentiated rat skeletal muscle myotubes which were treated with insulin and samples were collected every 20 min for 8 hours. Pooled samples at every hour were analyzed by gene array approach to measure transcript levels. The patterns of transcript levels were analyzed based on a novel method that integrates selection, clustering, and functional annotation to find the main temporal patterns associated to functional groups of differentially expressed genes. 326 genes were found to be differentially expressed in response to in vitro insulin administration in skeletal muscle myotubes. Approximately 20 % of the genes that were differentially expressed were identified as belonging to the insulin signaling pathway. Characteristic transcriptional temporal patterns include: (a) a slow and gradual decrease in gene expression, (b) a gradual increase in gene expression reaching a peak at about 5 hours and then reaching a plateau or an initial decrease and other different variable pattern of increase in gene expression over time. Conclusion/Significance: The new method allows identifying characteristic dynamic responses to insulin stimulus, commo

Heart Carcinoid Disease with Patent Foramen Ovale Treated by Mini Sternotomy

This case report was an attempt to present the importance of diagnostic echocardiography and closure of a patent foramen ovale in carcinoid heart disease. Herein, we present a case of a 48-year-old woman with a carcinoid metastasis presenting with tricuspid regurgitation, pulmonic stenosis, patent foramen ovale, and borderline left ventricular ejection fraction on an echocardiogram. Surgical intervention included closing the patent foramen ovale and replacing the tricuspid valve via mini-sternotomy. The tricuspid valve was repaired and the ejection fraction was preserved. The patient had an uncomplicated post-operative course. As indicated in this report, closing the patent foramen ovale along with fixing malfunctioning valves can improve the ejection fraction and the associated symptoms

Avoidance of Dialysis in an End-Stage Renal Disease Patient Status-post Off-pump Coronary Artery Bypass Grafting

Certain benefits are clearly associated with the use of off-pump coronary artery bypass grafting (CABG) as compared with the on-pump CABG. The superiority is more evident in patients with multiple co morbidities including renal failure.We reviewed the medical records of a 67-year-old male with a past medical history that was significant for multiple cardiovascular diseases and new-onset end-stage renal disease. The case was suffering from dyspnea and work-up was suggestive of non-ST elevation myocardial infarction and congestive heart failure.During the hospital course, he developed end-stage renal disease requiring hemodialysis. Further cardiac evaluation presented three-vessel coronary artery disease. The patient underwent off-pump CABG. Post-operatively, the patient had minimal complications and did not receive hemodialysis for 53 days.Off-pump CABG has evident short-term benefits for patients with the end-stage renal disease requiring dialysis, including possible improvement in cardiac function and avoidance of hemodialysi

High-risk Coronary Artery Bypass Grafting and Mitral Valve Replacement in a HIV Positive Patient

Certain subsets of high-risk mitral valve patients are not suitable candidates for transcatheter therapies. The objective of this report is to present a young patient with combined mitral valve and coronary artery disease to illustrate these challenges.In this report, we present a 47-year-old man with longstanding HIV infection who was referred with severe mitral regurgitation (MR) and profound cardiomyopathy to highlight the importance of decision-making and perioperative management.A 47-year-old HIV positive man with New York Heart Association class IV congestive heart failure was found to have severe MR (mixed Carpentier Type I and IIIB pathologies). The last viral load titer of the patient was undetectable. Cardiac catheterization revealed a chronic total occlusion of the middle of left anterior descending artery, ostial obtuse marginal and 70% posterior descending artery lesion, as well as severe pulmonary hypertension (PAP of 70/30 (mean: 43)), and a pulmonary vascular resistance of 4.6 Woods units. Preoperative cardiac magnetic resonance imaging showed left ventricular ejection fraction of 20%, right ventricular ejection fraction of 30%, nonviable circumflex distribution and scattered viability in the anterior and inferior cardiac walls. He underwent a high-risk coronary artery blood grafting plus mitral valve (MV) replacement (with intra-aortic balloon pump support). The postoperative course was complicated by gastrointestinal bleeding requiring transfusion, aspiration pneumonitis, atrial flutter and difficile colitis. However, the patient recovered appropriately, and remained asymptomatic and healthy in three months follow-up postoperatively. Application of transcatheter MV or device-assisted therapies for high-risk patients with severe MR might be limited due to financial, medical or social situations. In these instances, high-risk mitral valve surgery may still be the choice treatment in the selected patients

Transcatheter Aortic Valve Replacement: A Review Article

Transcatheter aortic valve replacement (TAVR) is a novel therapeutic intervention for the replacement of severely stenotic aortic valves in high-risk patients for standard surgical procedures. Since the initial PARTNER trial results, use of TAVR has been on the rise each year. New delivery methods and different valves have been developed and modified in order to promote the minimally invasive procedure and reduce common complications, such as stroke. This review article focuses on the current data on the indications, risks, benefits, and future directions of TAVR. Recently, TAVR has been considered as a standard-of-care procedure. While this technique is used frequently in high-risk surgical candidates, studies have been focusing on the application of this method for younger patients with lower surgical risk. Moreover, several studies have proposed promising results regarding the use of valve-in-valve technique or the procedure in which the valve is placed within a previously implemented bioprosthetic valve. However, ischemic strokes and paravalvular leak remain a matter of debate in these surgeries. New methods and devices have been developed to reduce the incidence of post-procedural stroke. While the third generation of TAVR valves (i.e., Edwards Sapien 3 and Medtronic Evolut R) addresses the issue of paravalvular leak structurally, results on their efficacy in reducing the risk of paravalvular leak are yet to be obtained. Furthermore, TAVR enters the field of hybrid methods in the treatment of cardiac issues via both surgical and catheter-based approaches. Finally, while TAVR is primarily performed on cases with aortic stenosis, new valves and methods have been proposed regarding the application of this technique in aortic regurgitation, as well as other aortic pathologies. TAVR is a suitable therapeutic approach for the treatment of aortic stenosis in high-risk patients. Considering the promising results in the current patient population, recent studies have been conducted to evaluate the efficacy of this approach as a standard-of-care procedure