A NEW METHOD OF SURGICAL TREATMENT OF LUMBAR SPINAL STENOSIS

As the treatment of lumbar or lumbosacral stenosis, laminectomy with the preservation of tissues supporting the spine and the embracement of the exposed dura mater with thin silicone rubber to prevent the occurrence of restenosis due to exuberant fibrous tissue formation at the operative site have been performed over a period of seven years. Before the prevention of restenosis with silicone rubber, we had to reoperate in cases which developed recurrent symptoms resulting from restenosis of the lumbosacral canal. This operation that we describe is technically feasible and with practical benefit can be done routinely for spinal decompression not only in the lumbosaral, but also in cervical spinal region without requiring an extensive laminectomy

INTRAOPERATIVE ANGIOGRAPHIC ASSESSMENT OF RECONSTRUCTED ARTERY AND USEFULNESS OF SAPHENOUS VEIN GRAFT BRIDGING IN EARLY THROMBOSIS OCCLUSION AFTER CAROTID ENDARTERECTOMY

Early postoperative thrombosis-occlusion of the internal carotid artery after carotid endarterectomy plays a major role in postoperative neurologic morbidity and mortality. To prevent this terrible complication, many surgeons are trying various prophylactic methods such as saphenous vein patch angioplasty, prolonged use of heparin, intraoperative Doppler ultrasound assessment, and so on. However, complete protection from postoperative thrombosis-occlusion is difficult. We have performed 47 carotid endarterectomies on 43 patients in the last three years. In 28 of these endarterectomies, primary closure for arteriotomy was performed, and in 19 cases, endarterectomies were reconstructed with saphenous vein patch angioplasty. An intraoperative angiographical assessment of the reconstructed segment was done in all endarterectomies after the reversing of heparin given during the carotid arterial surgical maneuver, and restenosis, or thrombosis-occlusion, was also checked. In three arteries, restenosis was demonstrated and repair was performed with vein graft angioplasty. Three of 28 arteries recontructed with primary closure and 1 of 19 arteries with vein patch angioplasty showed thrombosis-occlusion. Although vein patch angioplasty was done immediately for the primarily closured arteries, occlusion occurred again in two arteries. One artery with patch angioplasty also reoccluded. For these arteries, saphenous vein graft bridging between common carotid artery with an intact intima and internal carotid artery with an intact intima was performed. Postoperative angiogram showed good blood flow through the vein graft bridge. These results suggest that intraoperative angiography gives important imformation about the reconstructed arterial segment and that saphenous vein bridging is very useful in arteries with thrombosis-occlusion following carotid endarterectomy

CLINICOPATHOLOGICAL STUDY OF CEREBRAL SUBCORTICAL CAVERNOUS ANGIOMA AS EPILEPTOGENIC FOCUS

The authors conducted a comparative histological study of two groups of patients with cerebral subcortical cavernous angioma. One group was composed of 5 asymptomatic cases detected accidentally. The other group was composed of 4 patients presenting as epilepsy. The results obtained may be summarized as follows ; 1) Hemosiderin deposit and gliosis were seen in all cases examined ; 2) Granulomatous change was a histological finding associated with epileptogenesis ; 3) The histological changes, starting with proliferation of collagen fibers and leading to hyaline degeneration, calcification, and then hemangioma calcificans, seem to represent a course of spontaneous healing, when viewed from epileptogenesis

Global Landscape of a Co-Expressed Gene Network in Barley and its Application to Gene Discovery in Triticeae Crops

Accumulated transcriptome data can be used to investigate regulatory networks of genes involved in various biological systems. Co-expression analysis data sets generated from comprehensively collected transcriptome data sets now represent efficient resources that are capable of facilitating the discovery of genes with closely correlated expression patterns. In order to construct a co-expression network for barley, we analyzed 45 publicly available experimental series, which are composed of 1,347 sets of GeneChip data for barley. On the basis of a gene-to-gene weighted correlation coefficient, we constructed a global barley co-expression network and classified it into clusters of subnetwork modules. The resulting clusters are candidates for functional regulatory modules in the barley transcriptome. To annotate each of the modules, we performed comparative annotation using genes in Arabidopsis and Brachypodium distachyon. On the basis of a comparative analysis between barley and two model species, we investigated functional properties from the representative distributions of the gene ontology (GO) terms. Modules putatively involved in drought stress response and cellulose biogenesis have been identified. These modules are discussed to demonstrate the effectiveness of the co-expression analysis. Furthermore, we applied the data set of co-expressed genes coupled with comparative analysis in attempts to discover potentially Triticeae-specific network modules. These results demonstrate that analysis of the co-expression network of the barley transcriptome together with comparative analysis should promote the process of gene discovery in barley. Furthermore, the insights obtained should be transferable to investigations of Triticeae plants. The associated data set generated in this analysis is publicly accessible at http://coexpression.psc.riken.jp/barley/

Effective Load-balancing via Migration and Replication in Spatial Grids

The unprecedented growth as well as the growing importance of available spatial data at geographically distributed locations has made efficient networking of such data a necessity for availability reasons. The emergence of grid computing coupled with large and powerful computer networks, which have the capability to connect thousands of geographically distributed computers worldwide, has opened a world of opportunities for such networking. This provides a strong motivation for designing a spatial grid which supports fast data retrieval and allows its users to transparently access data of any location from anywhere. However, several challenging issues need to be addressed for the spatial grid to work efficiently in practice. In particular, mechanisms for efficient search and effective load-balancing need to be in place. This paper focusses on dynamic load-balancing in spatial grids via data migration/replication to prevent degradation in system performance owing to severe load imbalance among the nodes. Notably, issues concerning load-balancing are more complex in case of grids than for traditional domains primarily because a grid usually spans across multiple administrative domains. The main contributions of our..

Application-aware Power Saving for Online Transaction Processing using Dynamic Voltage and Frequency Scaling in a Multicore Environment

Abstract. Power consumption in data centers has been growing remarkably recent years, and power saving of their servers is essential. For power saving of these servers, power saving of an online transaction processing (OLTP) systems, which are major applications in data centers, is important. The OLTP system consumes relatively large amount of power because it is often equipped with a lot of computing and storage resources. Its power saving is difficult because it is required to meet a service level agreement (SLA), and few power saving technologies have been proposed so far. In this paper, we proposed an application-aware power saving for OLTP in a multicore environment. Our proposed methodology aims to save power consumption of OLTP systems by dynamically scaling the operating frequency of processors based on response time observation. Response time is often an important metric of SLA. Application-aware power saving enables power saving in such systems subject to SLAs. In our experimental evaluations using industrial standard benchmark TPC-C and real server workloads, 7.6% of total power consumption was saved. This reduction corresponds to 1000kJ a day in a typical entry level server

Early Experience and Evaluation of File Systems on SSD with Database Applications

Abstract-Flash SSDs are being incorporated in many enterprise storage platforms recently. However, the characteristics of the flash SSD are quite different from that of hard disk. The IO strategies in the existing systems should be carefully evaluated. This paper provides an evaluation on the flash-based transaction processing system. Two file systems, traditional inplace update-based file system and log-structured file system, are selected as the representative of two write strategies. Usually, the log-structured file system is believed to play better on flash SSDs. Our experiment shows that the performance results of two database applications are diverse with two file systems on different flash SSDs. We analyze the performance in different configurations. Based on the analysis, we provide our experience on building the flash-based database system to better utilize the performance benefits of flash SSDs