Kawasaki syndrome: an intriguing disease with numerous unsolved dilemmas

More than 40 years have passed since Kawasaki syndrome (KS) was first described. Yet KS still remains an enigmatic illness which damages the coronary arteries in a quarter of untreated patients and is the most common cause of childhood-acquired heart disease in developed countries. Many gaps exist in our knowledge of the etiology and pathogenesis of KS, making improvements in therapy difficult. In addition, many KS features and issues still demand further efforts to achieve a much better understanding of the disease. Some of these problem areas include coronary artery injuries in children not fulfilling the classic diagnostic criteria, genetic predisposition to KS, unpredictable ineffectiveness of current therapy in some cases, vascular dysfunction in patients not showing echocardiographic evidence of coronary artery abnormalities in the acute phase of KS, and risk of potential premature atherosclerosis. Also, the lack of specific laboratory tests for early identification of the atypical and incomplete cases, especially in infants, is one of the main obstacles to beginning treatment early and thereby decreasing the incidence of cardiovascular involvement. Transthoracic echocardiography remains the gold-standard for evaluation of coronary arteries in the acute phase and follow-up. In KS patients with severe vascular complications, more costly and potentially invasive investigations such as coronary CT angiography and MRI may be necessary. As children with KS with or without heart involvement become adolescents and adults, the recognition and treatment of the potential long term sequelae become crucial, requiring that rheumatologists, infectious disease specialists, and cardiologists cooperate to develop specific guidelines for a proper evaluation and management of these patients. More education is needed for physicians and other professionals about how to recognize the long-term impact of systemic problems related to KS

Medium-size-vessel vasculitis

Medium-size-artery vasculitides do occur in childhood and manifest, in the main, as polyarteritis nodosa (PAN), cutaneous PAN and Kawasaki disease. Of these, PAN is the most serious, with high morbidity and not inconsequential mortality rates. New classification criteria for PAN have been validated that will have value in epidemiological studies and clinical trials. Renal involvement is common and recent therapeutic advances may result in improved treatment options. Cutaneous PAN is a milder disease characterised by periodic exacerbations and often associated with streptococcal infection. There is controversy as to whether this is a separate entity or part of the systemic PAN spectrum. Kawasaki disease is an acute self-limiting systemic vasculitis, the second commonest vasculitis in childhood and the commonest cause of childhood-acquired heart disease. Renal manifestations occur and include tubulointerstitial nephritis and renal failure. An infectious trigger and a genetic predisposition seem likely. Intravenous immunoglobulin (IV-Ig) and aspirin are effective therapeutically, but in resistant cases, either steroid or infliximab have a role. Greater understanding of the pathogenetic mechanisms involved in these three types of vasculitis and better long-term follow-up data will lead to improved therapy and prediction of prognosis

Application of Fuzzy Control Theory in Resource Management of a Consolidated Server

Abstract—A virtualized system incorporates multiple systems into a single physical computer as virtual domains. A lot of data centers and server systems have been organized using virtualization technology to merge several computer systems. On the shared system, resource manager is the key affecting the performance. However, the resource management in current systems does not provide accurate resource allocation, because it only utilizes information from virtual machines and disregards the state of running applications. The paper demonstrates the CPU resource controller taking the state of application as inputs to produce the minimum resource retaining application performance in acceptable level. In particular, it employs two-layered controller. The first layer controller makes resource request based on the relationship between the state and resource demand of each application, modeled by fuzzy control theory. This approach is efficient to represent resource allocation model since fuzzy control theory deals imprecise and uncertain problems. The second layer controller adjusts the requests to the system capacity and builds the layout of resource capacity based on the relative Quality of Service performances between applications. For the separation of resource, common resource controller imposes a hard limit on the amount of resource a given domain can consume. The controller allocates resource with most effective capacity configuration. Under certain specified conditions, the controller does not set the capacities and allows domains to use the free time if the resource is idle. This results in eliminating unused resources and achieves relative high resource usage. Finally, the resource controller is evaluated with a virtualized system, and its advantages over conventional resource allocation methods are shown. I

Workload Analysis of SPECmail2009

Abstract—SPECmail2009 is a new benchmark suite for measuring the performance of corporate mail servers. It assumes the IMAP4 protocol for retrieving messages and a large fraction of transactions are for manipulating hierarchical messages and mail folders from the users connected via high-speed networks. In this paper, we present a performance analysis of SPECmail2009, including disk I/O behavior, quality of service metrics, and CPU time breakdown. The IMAP4’s capability of directly manipulating the messages on the server makes SPECmail2009 a highly I/Obound workload. Our experiments show that a combination of a small but fast access SCSI drive for indexing messages and larger but slower SATA drives for message files can be an option for building a cost-effective mail storage. Both of multiprocessing and multithreading are quite effective for SPECmail2009 especially intheusermodeexecution. Keywords: Mail server, performance analysis, disk I/O. I