bluuebunny/crossref_metadata_2025 huggingface dataset:
Vigilant
Authors: Pelleg Dan , Ben-Yehuda Muli , Harper Rick , Spainhower Lisa , Adeshiyan Tokunbo
Published: February 2008

What do our computer systems do all day? How do we make sure they continue doing it when failures occur? Traditional approaches to answering these questions often involve in-band monitoring agents. However in-band agents suffer from several drawbacks: they need to be written or customized for every workload (operating system and possibly also application), they comprise potential security liabilities, and are themselves affected by adverse conditions in the monitored systems.

Virtualization technology makes it possible to encapsulate an entire operating system or application instance within a virtual object that can then be easily monitored and manipulated without any knowledge of the contents or behavior of that object. This can be done out-of-band, using general purpose agents that do not reside inside the object, and hence are not affected by the behavior of the object.

This paper describes
Vigilant
, a novel way of monitoring virtual machines for problems. Vigilant requires no specialized agents inside a virtual object it is monitoring. Instead, it uses the hypervisor to directly monitor the resource requests and utilization of an object. Machine learning methods are then used to analyze the readings. Our experimental results show that problems can be detected out-of-band with high accuracy. Using Vigilant we demonstrate that out-of-band monitoring using virtualization and machine learning can accurately identify faults in the guest OS, while avoiding the many pitfalls associated with in-band monitoring.
Parallelization of IBM mambo system simulator in functional modes
Authors: Wang Kun , Zhang Yu , Wang Huayong , Shen Xiaowei
Published: February 2008

Mambo [4] is IBM's full-system simulator which models PowerPC systems, and provides a complete set of simulation tools to help IBM and its partners in pre-hardware development and performance evaluation for future systems. Currently Mambo simulates target systems on a single host thread. When the number of cores increases in a target system, Mambo's simulation performance for each core goes down. As the so-called "multi-core era" approaches, both target and host systems will have more and more cores. It is very important for Mambo to efficiently simulate a multi-core target system on a multi-core host system. Parallelization is a natural method to speed up Mambo under this situation.

Parallel Mambo (P-Mambo) is a multi-threaded implementation of Mambo. Mambo's simulation engine is implemented as a user-level thread-scheduler. We propose a multi-scheduler method to adapt Mambo's simulation engine to multi-threaded execution. Based on this method a core-based module partition is proposed to achieve both high inter-scheduler parallelism and low inter-scheduler dependency. Protection of shared resources is crucial to both correctness and performance of P-Mambo. Since there are two tiers of threads in P-Mambo, protecting shared resources by only OS-level locks possibly introduces deadlocks due to user-level context switch. We propose a new lock mechanism to handle this problem. Since Mambo is an on-going project with many modules currently under development, co-existence with new modules is also important to P-Mambo. We propose a global-lock-based method to guarantee compatibility of P-Mambo with future Mambo modules.

We have implemented the first version of P-Mambo in functional modes. The performance of P-Mambo has been evaluated on the OpenMP implementation of NAS Parallel Benchmark (NPB) 3.2 [12]. Preliminary experimental results show that P-Mambo achieves an average speedup of 3.4 on a 4-core host machine.
Migration policies for multi-core fair-share scheduling
Authors: Choffnes David , Astley Mark , Ward Michael J.
Published: February 2008

In this paper, we describe an extension of the Linux kernel scheduler called the Practical Fair-Share Scheduler (PFS). PFS is a fair-share process scheduler designed to support real-time workloads with
soft
(
i.e.
, elastic) timeliness requirements. Fair-share scheduling is a common choice for soft real-time systems since it is work conserving and ensures a minimum CPU allocation for each process. A novel aspect of PFS is its treatment of placement and migration in SMP or multi-core settings. Other fair-share schedulers have used ad hoc policies for handling these issues, often leading to underutilization and increased system lag. In contrast, PFS uses a strategy that maintains utilization without unfairly penalizing processes. We spend the remainder of this paper discussing placement and migration. A more extensive description of PFS, including source code, can be found at the download site listed in the citations.
Server virtualization in autonomic management of heterogeneous workloads
Authors: Steinder Malgorzata , Whalley Ian , Chess David
Published: February 2008

Server virtualization opens up a range of new possibilities for autonomic datacenter management, through the availability of new automation mechanisms that can be exploited to control and monitor tasks running within virtual machines. This facilitates more powerful and flexible autonomic controls, through management software that maintains the system in a desired state in the face of changing workload and demand. This paper explores in particular the use of server virtualization technology in the autonomic management of data centers running a heterogeneous mix of workloads. We present a system that manages heterogeneous workloads to their performance goals and demonstrate its effectiveness via real-system experiments and simulation.
Duality of virtualization
Authors: Fong Liana , Steinder Malgorzata
Published: February 2008

In recent years, virtualization has gained much in visibility and importance in the information technology (IT) industry. Many analyst reports, including IDC [1] and EMA [2], indicated ever increasing number of companies deployed virtualization to their production environments. There is also tremendous momentum from industrial vendors in creating new virtualization enablers along with their management functions. Some vendors engage in activities of standardizing common abstractions for various virtual entities at different virtualization layers.
SIP message classification
Authors: Acharya Arup , Wang Xiping , Wright Charles
Published: February 2008

We present a design sketch of a
programmable
classification engine for SIP (Session Initiation Protocol) messages and an outline of its implementation in the Linux kernel. In addition to classifying messages, it can extract and maintain state information across multiple messages. We apply the classifier for overload control using operator-specified rules.
Pyr.mea.IT
Authors: Agarwal Sheetal , Chakraborty Dipanjan , Challa Swati , Kambhatla Nandakishore , Kumar Arun , Mukherjea Sougata , Nanavati Amit Anil , Rajput Nitendra
Published: February 2008

Most of the existing IT applications are designed to cater to a small fraction of the human population. The precluded set consists of more than a billion people who either cannot afford a PC and Internet or are not skilled enough to be able to use them. However, the IT needs of this segment is similar in nature and perhaps more crucial than that of the current user segment. Designing systems for these underprivileged people poses several technological challenges: Due to low literacy levels the user interface has to be radically simplified, and the user devices have to be affordable. These and other requirements motivate a shift of complexity and computation from end-user devices to the network, tremendously increasing the expectations from the infrastructure. In this paper, we present an overview of technology developed and solutions built under Pyr.mea.IT project towards enabling IT for the masses.
Storage virtualization using a block-device file system
Authors: Faibish Sorin , Fridella Stephen , Bixby Peter , Gupta Uday
Published: February 2008

The design and organization of modern file systems has been traditionally driven by practical considerations related to the physical properties of computer disks Storage virtualization makes such considerations largely irrelevant, and file-system designs based on them perform sub-optimally in a virtual storage environment. One important example of this phenomenon is the relationship between disk seek times and the placement and organization of file system meta-data. In this paper we show that traditional approaches to organizing meta-data in file systems are closely related to assumptions about the physical properties of disks and that for this reason traditional file systems fail to materialize the full benefits of storage virtualization. We go on to propose a different file system organization of data and meta-data designed to exploit the power of virtualized storage.
Virtual machine time travel using continuous data protection and checkpointing
Authors: Ta-Shma Paula , Laden Guy , Ben-Yehuda Muli , Factor Michael
Published: February 2008

Virtual machine (VM) time travel enables reverting a virtual machine's state, both transient and persistent, to past points in time. This capability can be used to improve virtual machine availability, to enable forensics on past VM states, and to recover from operator errors. We present an approach to virtual machine time travel which combines Continuous Data Protection (CDP) storage support with live-migration-based virtual machine checkpointing. In particular, we present a novel approach for CDP which enables efficient reverts of the storage state to past points in time and makes it possible to
undo
a revert, and this is achieved using a simple branched-temporal data structure. We also present a design and implementation of a simple live-migration-based checkpointing mechanism in Xen.
Sharing is caring
Authors: Henderson Tristan
Published: February 2008

The networking research community lacks a tradition of sharing experimental data, or using such data for reproducing results. But are we really that bad? Are we worse than researchers in other fields? And if so, how can we do better?
ECHOS
Authors: Laoutaris Nikolaos , Rodriguez Pablo , Massoulie Laurent
Published: February 2008

In this paper we propose a radical solution to data hosting and delivery for the Internet of the future. The current data delivery architecture is "network centric", with content stored in data centers connected directly to Internet backbones. This approach has multiple drawbacks among which complexity of deploying data centers, power consumption, and lack of scalability are the most critical. We propose a totally innovative and orthogonal approach to traditional data centers, through what we call "nano" data centers, which are deployed in boxes at the edge of the network (e.g., in home gateways, set-top-boxes, etc.) and accessed using a new peer-to-peer communication infrastructure. Unlike traditional peer-to-peer clients, however, our nano data centers operate under a common management authority, e.g., the ISP who installs and maintains the set-top-boxes, and can thus cooperate more effectively and achieve a higher aggregate performance. Nano data centers are, therefore, better suited for providing guaranteed quality to new emerging applications such as online gaming, interactive IPTV and VoD, and user generated content
Feedback scheduling
Authors: Xia Feng , Tian Guosong , Sun Youxian
Published: February 2008

Embedded computing systems today increasingly feature resource constraints and workload variability, which lead to uncertainty in resource availability. This raises great challenges to software design and programming in multitasking environments. In this paper, the emerging methodology of feedback scheduling is introduced to address these challenges. As a closed-loop approach to resource management, feedback scheduling promises to enhance the flexibility and resource efficiency of various software programs through dynamically distributing available resources among concurrent tasks based on feedback information about the actual usage of the resources. With emphasis on the behavioral design of feedback schedulers, we describe a general framework of feedback scheduling in the context of real-time control applications. A simple yet illustrative feedback scheduling algorithm is given. From a programming perspective, we describe how to modify the implementation of control tasks to facilitate the application of feedback scheduling. An event-driven paradigm that combines time-triggered and event-triggered approaches is proposed for programming of the feedback scheduler. Simulation results argue that the proposed event-driven paradigm yields better performance than time-triggered paradigm in dynamic environments where the workload varies irregularly and unpredictably.
Letter from the chair
Authors: Sipior Janice C. , Lending Diane , Amoroso Donald L. , Shayo Conrad , Vowels Susan A.
Published: February 2008

Happy New Year! I hope 2008 brings you health, happiness, and good cheer!

It was so good to see everyone who attended the "Seventh Annual ACM-SIGMIS Networking Reception," held as an ACM-SIGMIS event prior to the International Conference on Information Systems (ICIS2007) in Montreal, Quebec, Canada. Thanks to those of you who attended. Please plan to attend this event next year. Mark your calendar now for Saturday, December 13, 2008, from 5:30-7:00pm, prior to ICIS2008 to be held in Paris, France, December 14-17, 2008.

Conference:
ACM-SIGMIS Computer Personnel Research 2008 (CPR2008)

Theme:
"Meeting increased demand for the next wave of Information Technology workers"

When & Where:
April 3-5, 2008, Charlottesville, Virginia, USA

Doctoral Consortium:
April 3, 2008

Website:
http://www.sigmis.org/Call_for_Papers_2008.pdf

For more information regarding ACM-SIGMIS CPR2008, please contact the Conference Co-Chairs:

Diane Lending, James Madison University, lendindc@jmu.edu

Chelley Vician, Michigan Tech University, cvician@mtu.edu.

For information regarding the Doctoral Consortium, please contact the Doctoral Consortium Co-Chairs:

K. D. Joshi, Washington State University, joshi@wsu.edu

Jo Ellen Moore, Southern Illinois University Edwardsville, joemoor@siue.edu

The venue for next year's CPR2009 is Limerick, Ireland. Please consider sending a submission by the October 2008 deadline. For more information, contact Norah Power, University of Limerick, norah.power@ul.ie. Your participation is welcome and encouraged!

Thanks for your support of SIGMIS. Should you have any questions, suggestions, or other input, please feel free to contact any one of us.

We look forward to seeing you at ACM-SIGMIS CPR2008 in April!
Investigations on the Fe-doped TiO2 Nanotube Arrays as a Photoanode for Cathodic Protection of Stainless Steel
Authors: Li Jing , Yun Hong , Lin Chang-Jian
Published: February 2008

A highly ordered Fe-doped TiO2 nanotube layer was fabricated by potentiostatic anodization of pure titanium in fluorinated electrolyte solutions containing iron ions. The structure and composition of the as-prepared TiO2 nanotubes were characterized by SEM, XRD and UV-Vis. The Fe-doped TiO2 nanotubes show a stronger absorption in the 410-650nm range. The performances of photogenerated cathodic protection and the photoelectrochemical response for the Fe-doped TiO2 nanotube layers under illumination and dark conditions were evaluated through the electrochemical measurements. It is found that the open-circuit potentials of 316 SS coupled with the Fe-doped TiO2 nanotubes layers shift negatively under visible light irradiation (λ>400nm). It is indicated that the Fe-doped TiO2 nanotubes layers are able to function effectively a photogenerated cathodic protection for metals under regular sunlight conditions.
Ionic Migration in Soldered Joints of a Printed Circuit Board
Authors: Neri Miguel A. , Carreño Caleb , Martínez Villafañe Alberto
Published: February 2008

The terminals of an electronic device soldered to a printed circuit board by the wave process were analyzed in order to determine the causes of a short-circuit localized between these terminals. Using the techniques of Stereoscopy and Scanninig Electron Microscopy (SEM) we identify dendrites formed between the soldered joints of such terminals. The dendrites were formed by the presence of flux wastes that came from the tin-lead solder and the presence of moisture in the printed circuit board (PCB). When an electric field was applied to the printed circuit board ionic migration was promoted between the solder joints of the terminals, growing tin-lead dendrites coming from the solder applied on the terminals. The dendrites grew with time until they caused a short-circuit between the soldered joints, producing system failure.
Induction of arachidonate 12-lipoxygenase (Alox15) in intestine of iron-deficient rats correlates with the production of biologically active lipid mediators
Authors: Collins James F. , Hu Zihua , Ranganathan P. N. , Feng Dian , Garrick Laura M. , Garrick Michael D. , Browne Richard W.
Published: February 2008

To identify novel genes associated with iron metabolism, we performed gene chip studies in two models of iron deficiency: iron-deprived rats and rats deficient in the principal intestinal iron transporter, divalent metal transporter 1 (i.e., Belgrade rats). Affymetrix rat genome gene chips were utilized (RAE230) with cRNA samples derived from duodenum and jejunum of experimental and control animals. Computational analysis and statistical data reduction identified 29 candidate genes, which were induced in both models of iron deficiency. Gene ontology analysis showed enrichment for genes related to lipid homeostasis, and one gene related to this physiological process, a leukocyte type, arachidonate 12-lipoxygenase ( Alox15), was selected for further examination. TaqMan real-time PCR studies demonstrated strong induction of Alox15 throughout the small and large intestine, and in the liver of iron-deficient rats. Polyclonal antibodies were developed and utilized to demonstrate that proteins levels are significantly increased in the intestinal epithelium of iron-deprived rats. HPLC analysis revealed altered intestinal lipid metabolism indicative of Alox15 activity, which resulted in the production of biologically active lipid molecules (12-HETE, 13-HODE, and 13-HOTE). The overall effect is a perturbation of intestinal lipid homeostasis, which results in the production of lipids essentially absent in the intestine of control rats. We have thus provided mechanistic insight into the alteration in lipid metabolism that occurs during iron deficiency, in that induction of Alox15 mRNA expression may be the primary event. The resulting lipid mediators may be related to documented alterations in villus structure and cell proliferation rates in iron deficiency, or to structural alterations in membrane lipid composition.
Role for NMDA receptors in visceral nociceptive transmission in the anterior cingulate cortex of viscerally hypersensitive rats
Authors: Wu Xiaoyin , Gao Jun , Yan Jin , Fan Jing , Owyang Chung , Li Ying
Published: February 2008

We have identified colorectal distension (CRD)-responsive neurons in the anterior cingulate cortex (ACC) and demonstrated that persistence of a heightened visceral afferent nociceptive input to the ACC induces ACC sensitization. In the present study, we confirmed that rostral ACC neurons of sensitized rats [induced by chicken egg albumin (EA)] exhibit enhanced spike responses to CRD. Simultaneous in vivo recording and reverse microdialysis of single ACC neurons showed that a low dose of glutamate (50 μM) did not change basal ACC neuronal firing in normal rats but increased ACC neuronal firing in EA rats from 18 ± 2 to 32 ± 3.8 impulses/10 s. A high dose of glutamate (500 μM) produced 1.95-fold and a 4.27-fold increases of ACC neuronal firing in sham-treated rats and in EA rats, respectively, suggesting enhanced glutamatergic transmission in the ACC neurons of EA rats. Reverse microdialysis of the 3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA)/kainite receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX; 10 μM) reduced basal and abolished CRD-induced ACC neuronal firing in normal rats. In contrast, microdialysis of N-methyl-d-aspartate (NMDA) receptor antagonist AP5 had no effect on ACC neuronal firing in normal rats. However, AP5 produced 86% inhibition of ACC neuronal firing evoked by 50 mmHg CRD in the EA rats. In conclusion, ACC nociceptive transmissions are mediated by glutamate AMPA receptors in the control rats. ACC responses to CRD are enhanced in viscerally hypersensitive rats. The enhancement of excitatory glutamatergic transmission in the ACC appears to mediate this response. Furthermore, NMDA receptors mediate ACC synaptic responses after the induction of visceral hypersensitivity.
Novel intestinal splice variants of RNA-binding protein CUGBP2: isoform-specific effects on mitotic catastrophe
Authors: Ramalingam Satish , Natarajan Gopalan , Schafer Chris , Subramaniam Dharmalingam , May Randal , Ramachandran Ilangovan , Queimado Lurdes , Houchen Courtney W. , Anant Shrikant
Published: February 2008

CUG triplet repeat-binding protein 2 (CUGBP2) is a RNA-binding protein that regulates mRNA translation and modulates apoptosis. Here, we report the identification of two splice variants (termed variants 2 and 3) in cultured human intestinal epithelial cells and in mouse gastrointestinal tract. The variants are generated from alternative upstream promoters resulting in the inclusion of additional NH2-terminal residues. Although variant 2 is the predominant isoform in normal intestine, its expression is reduced, whereas variant 1 is overexpressed following γ-irradiation. All three variants bind cyclooxygenase-2 (COX-2) mRNA. However, only variant 1 inhibits the translation of the endogenous COX-2 mRNA and a chimeric luciferase mRNA containing the COX-2 3′untranslated region. Furthermore, whereas variant 1 is predominantly nuclear, variants 2 and 3 are predominantly cytoplasmic. These data imply that the additional amino acids affect CUGBP2 function. Previous studies have demonstrated that variant 1 induces intestinal epithelial cells to undergo apoptosis. However, in contrast to variant 1, the two novel variants do not affect proliferation or apoptosis of HCT116 cells. In addition, only variant 1 induced G2/M cell cycle arrest, which was overcome by prostaglandin E2. Moreover, variant 1 increased cellular levels of phosphorylated p53 and Bax and decreased Bcl2. Caspase-3 and -9 were also activated, suggesting the initiation of the intrinsic apoptotic pathway. Furthermore, increased phosphorylation of checkpoint kinase (Chk)1 and Chk2 kinases and increased nuclear localization of Cdc2 and cyclin B1 suggested that cells were in mitotic transition. Taken together, these data demonstrate that cells expressing CUGBP2 variant 1 undergo apoptosis during mitosis, suggesting mitotic catastrophe.
Opioid modulation of ferret vagal afferent mechanosensitivity
Authors: Page Amanda J. , O'Donnell Tracey A. , Blackshaw L. Ashley
Published: February 2008

Despite universal use of opioids in the clinic to inhibit pain, there is relatively little known of their peripheral actions on sensory nerve endings, where in fact they may be better targeted with more widespread applications. Here we show differential effects of μ-, κ-, and δ-opioids on mechanosensitive ferret esophageal vagal afferent endings investigated in vitro. The effects of selective agonists [d-Ala2,N-Me-Phe4,Gly-ol5]-enkephalin (DAMGO), 2-(3, 4-dichlorophenyl)- N-methyl- N-[(1S)-1phenyl-2-(1-pyrrolidinyl) ethyl] acetamide hydrochlorine (ICI 199441), and (+)-4-[(αR)-α-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]- N, N-diethylbenzamide (SNC-80), respectively, on mechanosensory stimulus-response functions were quantified. DAMGO (10−7to 10−5M) reduced the responses of tension receptors to circumferential tension (1–5 g) by up to 50%, and the responses of mucosal receptors to mucosal stroking (10–1,000 mg von Frey hair) by >50%. DAMGO effects were reversed by naloxone (10−5M). Tension/mucosal (TM) receptor responses to tension and stroking were unaffected by DAMGO. ICI 199441 (10−6to 10−5M) potently inhibited all responses except TM receptor responses to tension, and SNC-80 (10−5to 10−3M) had no effect other than a minor inhibition of mucosal receptor responses to intense stimuli at 10−3M. We conclude that μ- and κ-opioids have potent and selective peripheral effects on esophageal vagal afferents that may have applications in treatment of disorders of visceral sensation.
CT-measured regional specific volume change reflects regional ventilation in supine sheep
Authors: Fuld Matthew K. , Easley R. Blaine , Saba Osama I. , Chon Deokiee , Reinhardt Joseph M. , Hoffman Eric A. , Simon Brett A.
Published: February 2008

Computer tomography (CT) imaging techniques permit the noninvasive measurement of regional lung function. Regional specific volume change (sVol), determined from the change in lung density over a tidal breath, should correlate with regional ventilation and regional lung expansion measured with other techniques. sVol was validated against xenon (Xe)-CT-specific ventilation (sV̇) in four anesthetized, intubated, mechanically ventilated sheep. Xe-CT used expiratory gated axial scanning during the washin and washout of 55% Xe. sVol was measured from the tidal changes in tissue density (H, houndsfield units) of lung regions using the relationship sVol = [1,000(Hi − He)]/[He(1,000 + Hi)], where He and Hi are expiratory and inspiratory regional density. Distinct anatomical markings were used to define corresponding lung regions of interest between inspiratory, expiratory, and Xe-CT images, with an average region of interest size of 1.6 ± 0.7 ml. In addition, sVol was compared with regional volume changes measured directly from the positions of implanted metal markers in an additional animal. A linear relationship between sVol and sV̇ was demonstrated over a wide range of regional sV̇ found in the normal supine lung, with an overall correlation coefficient ( R2) of 0.66. There was a tight correlation ( R2 = 0.97) between marker-measured volume changes and sVol. Regional sVol, which involves significantly reduced exposure to radiation and Xe gas compared with the Xe-CT method, represents a safe and efficient surrogate for measuring regional ventilation in experimental studies and patients.
Potential sources of oxidative stress that induce postexercise proteinuria in rats
Authors: Koçer Günnur , Şentürk Ümit Kemal , Kuru Oktay , Gündüz Filiz
Published: February 2008

Exercise-induced proteinuria is a common consequence of physical activity and is caused predominantly by alterations in renal hemodynamics. Although it has been shown that exercise-induced oxidative stress can also contribute to the occurrence of postexercise proteinuria, the sources of reactive oxygen species that promote it are unknown. We investigated the enzymes nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and xanthine oxidase (XO) as possible sources of oxidative stress in postexercise proteinuria. First, we evaluated the effect of blocking the NADPH oxidase enzyme on postexercise proteinuria. We found a significant increase in urinary protein level, kidney thiobarbituric acid-reactive substances (TBARS), and protein carbonyl content after exhaustive exercise, and NADPH oxidase activity was induced by exercise. Rats that were treated with an NADPH oxidase inhibitor for 4 days before exhaustive exercise showed no increase in kidney TBARS or protein carbonyl derivative level and no proteinuria or NADPH oxidase activation. In the next set of experiments, we investigated the effect of XO blockage on postexercise proteinuria. Oxypurinol, an XO inhibitor was administered to rats for 3 days before exercise. Although XO inhibition significantly decreased kidney TBARS levels and protein carbonyl content in exercised rats, the inhibition did not prevent exercise-induced proteinuria. However, plasma and kidney XO activity was not induced by exercise, but rather it was suppressed under oxypurinol treatment. These results suggest that increased NADPH oxidase activity induced by exhaustive exercise is an important source of elevated oxidative, stress during exercise, which contributes to the occurrence of postexercise proteinuria.
Diagnostic Markers for Early Detection of Ovarian Cancer
Authors: Visintin Irene , Feng Ziding , Longton Gary , Ward David C. , Alvero Ayesha B. , Lai Yinglei , Tenthorey Jeannette , Leiser Aliza , Flores-Saaib Ruben , Yu Herbert , Azori Masoud , Rutherford Thomas , Schwartz Peter E. , Mor Gil
Published: February 2008

Purpose: Early detection would significantly decrease the mortality rate of ovarian cancer. In this study, we characterize and validate the combination of six serum biomarkers that discriminate between disease-free and ovarian cancer patients with high efficiency.

Experimental Design: We analyzed 362 healthy controls and 156 newly diagnosed ovarian cancer patients. Concentrations of leptin, prolactin, osteopontin, insulin-like growth factor II, macrophage inhibitory factor, and CA-125 were determined using a multiplex, bead-based, immunoassay system. All six markers were evaluated in a training set (181 samples from the control group and 113 samples from OC patients) and a test set (181 sample control group and 43 ovarian cancer).

Results: Multiplex and ELISA exhibited the same pattern of expression for all the biomarkers. None of the biomarkers by themselves were good enough to differentiate healthy versus cancer cells. However, the combination of the six markers provided a better differentiation than CA-125. Four models with <2% classification error in training sets all had significant improvement (sensitivity 84%-98% at specificity 95%) over CA-125 (sensitivity 72% at specificity 95%) in the test set. The chosen model correctly classified 221 out of 224 specimens in the test set, with a classification accuracy of 98.7%.

Conclusions: We describe the first blood biomarker test with a sensitivity of 95.3% and a specificity of 99.4% for the detection of ovarian cancer. Six markers provided a significant improvement over CA-125 alone for ovarian cancer detection. Validation was performed with a blinded cohort. This novel multiplex platform has the potential for efficient screening in patients who are at high risk for ovarian cancer.
Characteristics and Outcomes of Patients with Seizures according to the Time of Onset in Relation to Stroke
Authors: De Reuck J. , Sieben A. , Van Maele G.
Published: February 2008

Background/Aim: Although most late-onset seizures (LS) appear within 2 years after stroke, some of them occur later and their characteristics are unknown. The aim of this study was to compare the characteristics of patients with very-late-onset seizures (VLS) to those with early-onset seizures (ES) and those with LS. Patients: The study group consisted of 204 patients with stroke-related seizures (29 ES, 128 LS and 47 VLS). Results: Intracranial haemorrhage was a more frequent cause of ES than of LS and no cause at all of VLS. On the other hand, 25% of the VLS were related to lacunar strokes. Status epilepticus occurred in 20.7% of the ES, in 11.7% of the LS and in 2.1% of the VLS patients. Seizure recurrences were 13.8% in the ES, 54.7% in the LS and 34.0% in the VLS group. Neurological impairment, at stroke onset, and the degree of disability were more severe in patients with ES compared to those with LS and were very mild in the VLS group. The EEG findings as a whole did not show significant differences between the three groups, although a normal EEG was more frequent in the VLS group. Conclusion: VLS occur in patients with minor ischaemic strokes with good recovery and benign disease course.
Errors in EEG Interpretation and Misdiagnosis of Epilepsy
Authors: Benbadis Selim R. , Lin Kaiwen
Published: February 2008

Background/Aims: The overinterpretation of EEGs is common and is an important contributor to the misdiagnosis of epilepsy. We reviewed our experience in order to clarify which EEG patterns are commonly overread as epileptiform. Methods: We identified patients who were seen at our epilepsy clinic and were ultimately diagnosed as having conditions other than epilepsy. We selected those who had previously had an EEG read as showing epileptiform discharges and whose EEG was available for our own re-review. Results: 37 patients met the above criteria. Eventual diagnoses were psychogenic nonepileptic seizures (10), syncope (7), other miscellaneous diagnoses (5) and unexplained nonspecific symptoms (15). None of the EEGs had epileptiform discharges. The descriptions of the abnormalities included ‘temporal sharp waves’ in 30, ‘frontal sharp waves’ in 2 and ‘generalized spike-wave complexes’ in 2. Three had no reports available to identify the alleged abnormality. The benign patterns mistaken for temporal (30) and frontal (2) sharp waves were simple fluctuations of background activity with temporal phase reversals. Conclusions: By far the most common patterns overread as epileptiform are nonspecific fluctuations of background in the temporal regions, which are misread as temporal sharp waves.
Anti-Inflammatory Agents and Cognitive Decline in a Bi-Racial Population
Authors: Grodstein Francine , Skarupski Kimberly A. , Bienias Julia L. , Wilson Robert S. , Bennett David A. , Evans Denis A.
Published: February 2008

In a prospective study among 4,409 subjects aged 65+ years, we assessed the relation of nonsteroidal anti-inflammatory agents (NSAIDs) to cognition. The main outcome was decline in global cognitive function, determined by average performance across four cognitive tests, over up to four interviews. We found similar rates of cognitive decline among recent users of aspirin and of other NSAIDs (largely ibuprofen) compared to those who did not use these NSAIDs. For lifetime duration of aspirin use, we failed to find an association with cognitive decline. However, for other NSAIDs, increasing duration of lifetime use was related to slower rates of cognitive decline, relative to no use of other NSAIDs (5+ years vs. no use: mean difference = 0.12; p trend = 0.03). Overall, we found no relation between regular aspirin use and cognitive decline, but long-term use of ibuprofen may be related to decreased rates of cognitive decline in older persons.
Prevalence of Stroke and Stroke Symptoms: A Population-Based Survey of 28,090 Participants
Authors: Jungehülsing G.J. , Müller-Nordhorn J. , Nolte C.H. , Roll S. , Rossnagel K. , Reich A. , Wagner A. , Einhäupl K.M. , Willich S.N. , Villringer A.
Published: February 2008

Background: Stroke is associated with a considerable burden of disease worldwide. Data about prevalence needs regular updating to facilitate health care planning and resource allocation. The purpose of the present study was to determine stroke prevalence in a large urban population in an easy and reliable way. Methods:In a population survey a total of 75,720 households with at least 1 person ≧50 years received information about stroke symptoms by mail. In addition, the Stroke Symptom Questionnaire assessing the prevalence of stroke and of stroke symptoms was sent. Stroke prevalence was determined by a single physician-diagnosed stroke-screening question or by the combination of the latter with reported visual impairment and/or articulation problems in the past. Results: A total of 28,090 persons responded (37.5%). Mean (±SD) age was 64.4 ± 9.7 years, 62.9 ± 8.9 for men (43.3%), and 65.5 ± 10.2 for women. Of all participants 2.7% reported impaired vision, 2.8% facial weakness, 2.8% articulation problems, 3.9% limb weakness, and 5% sensory disturbances. A total of 4.5% reported a physician-diagnosed stroke (women 4.3%; men 4.9%). Combining reported stroke history with reported impaired vision and/or articulation problems, the prevalence of stroke increased to 7.6% (men 8.4%; women 7.2%). Factors associated with higher prevalence were higher age, male gender, non-German nationality, lower education, positive family history of stroke, and living alone. Conclusions: The combination of questions concerning a prior stroke and stroke symptoms is a useful and easy approach to assess prevalence. It results in prevalence numbers which might compensate for an underestimation of stroke numbers.
The Mayo Clinic Study of Aging: Design and Sampling, Participation, Baseline Measures and Sample Characteristics
Authors: Roberts Rosebud O. , Geda Yonas E. , Knopman David S. , Cha Ruth H. , Pankratz V. Shane , Boeve Bradley F. , Ivnik Robert J. , Tangalos Eric G. , Petersen Ronald C. , Rocca Walter A.
Published: February 2008

Background: The objective of this study was to establish a prospective population-based cohort to investigate the prevalence, incidence and risk factors for mild cognitive impairment (MCI) and dementia. Methods: The Olmsted County, Minn., population, aged 70–89 years on October 1, 2004, was enumerated using the Rochester Epidemiology Project. Eligible subjects were randomly selected and invited to participate. Participants underwent a comprehensive in-person evaluation including the Clinical Dementia Rating Scale, a neurological evaluation and neuropsychological testing. A consensus diagnosis of normal cognition, MCI or dementia was made by a panel using previously published criteria. A subsample of subjects was studied via telephone interview. Results: Four hundred and two subjects with dementia were identified from a detailed review of their medical records but were not contacted. At baseline, we successfully evaluated 703 women aged 70–79 years, 769 women aged 80–89 years, 730 men aged 70–79 years and 517 men aged 80–89 years (total n = 2,719). Among the participants, 2,050 subjects were evaluated in person and 669 via telephone. Conclusions: Strengths of the study are that the subjects were randomly selected from a defined population, the majority of the subjects were examined in person, and MCI was defined using published criteria. Here, we report the design and sampling, participation, baseline measures and sample characteristics.
Effects of Tryptophan Depletion on Cognitive Functioning, Obsessive-Compulsive Symptoms and Mood in Obsessive-Compulsive Disorder: Preliminary Results
Authors: Külz Anne Katrin , Meinzer Sandra , Kopasz Marta , Voderholzer Ulrich
Published: February 2008

Background: Previous studies suggest that obsessive-compulsive disorder (OCD) is associated with moderate cognitive deficits. There is also evidence for altered serotonergic transmission in OCD. The aim of this study was to evaluate the impact of rapid plasma tryptophan depletion on cognitive functioning in OCD. Methods: A double-blind crossover study was conducted to explore the effects of tryptophan depletion on cognitive functioning, obsessive or compulsive (OC) symptoms and mood in OCD patients treated with selective serotonin reuptake inhibitors. Results: After 5 h of tryptophan depletion, 6 out of 7 patients reported worsening of mood (placebo condition: 3 patients). No effect was found regarding OC symptoms. There was a small and nonsignificant improvement of nonverbal memory and fluency. Problem solving ability and verbal memory, in contrast, were slightly impaired after tryptophan depletion. The results, however, represented only tendencies without reaching significance. Conclusion: The results suggest that OC symptoms may not depend on the short-time availability of serotonin. As some critical cognitive functions improved following tryptophan depletion, there is no evidence from our study that neuropsychological impairment in OCD can be reduced to a lowered level of serotonin. Future studies are needed to further clarify these findings by use of larger samples.
Association Study of Dopamine Receptor D2TaqI A Polymorphism and Reward-Related Personality Traits in Healthy Korean Young Females
Authors: Lee So Hee , Ham Byung-Joo , Cho Youl-Hee , Lee Seung-Min , Shim Sung Han
Published: February 2008

Background: Genetic factors make a significant contribution to the determination of human personality traits. We aimed to investigate the possible relationship between dopamine receptor D2 (DRD2) TaqI A polymorphism and the reward-related personality traits as measured by the Carver and White Behavioral Inhibition System/Behavioral Approach System (BIS/BAS) scales and Cloninger’s Temperament and Character Inventory (TCI). Methods: The sample consisted of 267 female healthy Korean unrelated university students (age: 23.12 ± 3.22 years) and they filled out the BIS/BAS scales and the TCI. Genomic DNA was isolated from whole blood and genotyped with the fluorescence polarization detection method. The effect of the independent variables (DRD2 genotypes) on the dependent variables were analyzed by multivariate and subsequent univariate ANOVA. Results: We found significant associations between the A1 allele of the DRD2 TaqI A polymorphism and a high BAS-RR score (reward responsiveness). No significant association was observed between DRD2 polymorphisms and other factors of the BIS/BAS scales and TCI. Conclusion: These findings suggest the notion that DRD2 TaqI A polymorphism contributes to high reward sensitivity, which measures anticipation and positive response towards reward.
Risk Factors for Febrile Morbidity after Abdominal Hysterectomy in a University Hospital in Thailand
Authors: Chirdchim Watcharin , Hanprasertpong Jitti , Prasartwanakit Visit , Geater Alan
Published: February 2008

Aim: To identify the risk factors for febrile morbidity after hysterectomy. Methods: This was a historical cohort study of 1,980 women who had undergone hysterectomy between October 1998 and December 2005. Multiple logistic regression was used to identify risk factors for febrile morbidity. Results: Among the cohort, 1,463 women were nonfebrile and 517 febrile – an incidence of febrile morbidity of 26.1%. The incidence of febrile morbidity was higher in patients with lower preoperative hematocrit, more extensive surgery, longer operative time, greater blood loss and malignant disease. The median intraoperative blood loss was 500 ml in the febrile group and 400 ml in the non-febrile group (p < 0.0005). Median operative time was 150 min in the febrile group and 135 min in the non-febrile group (p < 0.0005). Two variables were identified as independent risk factors for febrile morbidity: intraoperative blood loss of ≧750 ml (compared with <250 ml OR 1.52; 95% CI 1.08–2.13; p = 0.036) and a diagnosis of malignant disease (OR 1.86; 95% CI 1.45–2.13; p < 0.0005). Conclusions: Independent risk factors for febrile morbidity were an intraoperative blood loss of ≧750 ml and malignant disease.
Nonattendance in Obstetrics and Gynecology Patients
Authors: Dreiher Jacob , Froimovici Miron , Bibi Yuval , Vardy Daniel A. , Cicurel Assi , Cohen Arnon D.
Published: February 2008

Background: Nonattendance for obstetrics and gynecology (OB/GYN) appointments disrupts medical care and leads to misuse of valuable resources. We investigated factors associated with nonattendance in an outpatient OB/GYN clinic. Methods: Nonattendance was examined for a period of 1 year in first-time visitors of an ambulatory OB/GYN clinic. The effects of age, population sector, the treating physician, waiting time, and timing of the appointment on the proportions of nonattendance were assessed. χ2 tests and logistic regression were used for simple and multiple regression models. Results: A total of 8,883 visits were included (median age 36 years). The proportion of nonattendance was 30.1%: 19.9% among rural Jewish, 30.5% in urban Jewish, and 36% in Bedouins (p < 0.001). Nonattendance increased from 26.6% among those waiting up to 1 week to 32.3% among those who waited more than 15 days (p < 0.001) and decreased with age (p < 0.001). A multiple logistic regression model demonstrated that age, population sector and waiting time for an appointment were significantly associated with nonattendance. Conclusion: Nonattendance in OB/GYN patients is independently associated with age, population sector and waiting time for an appointment. It is suggested that various solutions should be carefully introduced assessed regarding routine patient scheduling in OB/GYN clinics.
Personality and Coping in Young Inmates: A Cluster Typology
Authors: Mohíno Susana , Kirchner Teresa , Forns Maria
Published: February 2008

Objective: Firstly, to identify groups of inmates according to personality. Secondly, to differentiate types of personality through coping strategies, psychopathology, criminal records and social factors. Method: A cross-sectional design was used to study psychosocial, correctional, personality and clinical characteristics in inmates. The group was composed of 106 male inmates. The measures used to evaluate personality, clinical and psychosocial variables were a standard protocol and three self-report questionnaires: the Millon Clinical Multiaxial Inventory-II, the Minnesota Multiphasic Personality Inventory-2 and the Coping Responses Inventory-Adult Form. A cluster analysis, ANOVA and Kruskall-Wallis test were conducted. Results: Four clusters were identified. The secondary type was characterized by an impulsive, suspicious, hostile personality, by anxiety, a low tolerance of frustration, and by the use of cognitive avoidance coping. The controlled-healthy type showed a less pathological and more self-controlled personality. The primarytype was similar to secondary, but with lower tendency to impulsivity. The inhibited-affected type was shown to have an avoidant personality, greater tendency to symptomatology and also to use acceptance-resignation and emotional discharge coping. Conclusion: The four groups of young inmates identified showed profiles with different degrees of psychopathological risk and also different coping profiles.
Toll-Like Receptor 2 and Renal Allograft Function
Authors: de Groot Kirsten , Kuklik Katharina , Bröcker Verena , Schwarz Anke , Gwinner Wilfried , Kreipe Hans , Haller Hermann , Fliser Danilo , Mengel Michael
Published: February 2008

Background: Toll-like receptors (TLR) modulate the immune response. We analyzed the relationships between TLR expression in renal tissue with infection, rejection and graft function after kidney transplantation. Methods: TLR-2 and TLR-4 expression was detected by immunohistochemistry in 257 protocol biopsies obtained 6 weeks, 3 and 6 months after transplantation, and in 108 indication biopsies. We correlated TLR expression in different renal tissue compartments with kidney transplant function 6, 12 and 24 months after transplantation, acute cellular rejection in renal grafts (according to the Banff classification), and urinary tract and cytomegalovirus infections. Results: We found a highly consistent correlation of TLR-2 expression in proximal and distal tubules, and in renal vessels (p < 0.001 for all compartments), but not for TLR-4 expression. This holds true for all protocol biopsy time points as well as for indication biopsies. Positive TLR-2 expression in renal tubules was associated with significantly (p < 0.05) better initial graft function as well as graft function 6, 12 and 24 months after transplantation. We also found a significant (p < 0.05) association between TLR-2 expression and lower incidence of acute cellular rejection in early protocol biopsies (6 weeks). In contrast, positive TLR-4 expression was not related to kidney function or acute cellular rejection. Further, the two different TLR subtypes were not related to episodes of urinary tract or cytomegalovirus infections. Conclusion: TLR-2 expression in renal tissue is associated with superior graft function up to 2 years after kidney transplantation. The role of TLR-2 in the immune response against human kidney transplants warrants further investigation.