bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship of Carbapenem Restriction in 22 University Teaching Hospitals to Carbapenem Use and Carbapenem-Resistant
Pseudomonas aeruginosa
Authors: Pakyz Amy L. , Oinonen Michael , Polk Ronald E. 
Published: March 2009

ABSTRACT

Many hospital antimicrobial stewardship programs restrict the availability of selected drugs by requiring prior approval. Carbapenems may be among the restricted drugs, but it is unclear if hospitals that restrict availability actually use fewer carbapenems than hospitals that do not restrict use. Nor is it clear if restriction is related to resistance. We evaluated the relationship between carbapenem restriction and the volume of carbapenem use and both the incidence rate and proportion of carbapenem-resistant
Pseudomonas aeruginosa
isolates from 2002 through 2006 in a retrospective, longitudinal, multicenter analysis among a consortium of academic health centers. Carbapenem use was measured from billing records as days of therapy per 1,000 patient days. Hospital antibiograms were used to determine both the incidence rate and proportion of carbapenem-resistant
P. aeruginosa
isolates. A survey inquired about restriction policies for antibiotics, including carbapenems. General linear mixed models were used to examine study outcomes. Among 22 hospitals with sufficient data for analysis, overall carbapenem use increased significantly over the 5 years of study (
P
< 0.0001), although overall carbapenem resistance in
P. aeruginosa
did not change. Hospitals that restricted carbapenems (
n
= 8; 36%) used significantly fewer carbapenems (
P
= 0.04) and reported lower incidence rates of carbapenem-resistant
P. aeruginosa
(
P
= 0.01) for all study years. Fluoroquinolone use was a potential confounder of these relationships, but hospitals that restricted carbapenems actually used fewer fluoroquinolones than those that did not. Restriction of carbapenems is associated with both lower use and lower incidence rates of carbapenem resistance in
P. aeruginosa
.
Campylobacter jejuniCocultured with Epithelial Cells Reduces Surface Capsular Polysaccharide Expression
Authors: Corcionivoschi N. , Clyne M. , Lyons A. , Elmi A. , Gundogdu O. , Wren B. W. , Dorrell N. , Karlyshev A. V. , Bourke B. 
Published: March 2009

ABSTRACTThe host cell environment can alter bacterial pathogenicity. We employed a combination of cellular and molecular techniques to study the expression ofCampylobacter jejunipolysaccharides cocultured with HCT-8 epithelial cells. After two passages, the amount of membrane-bound high-molecular-weight polysaccharide was considerably reduced. Microarray profiling confirmed significant downregulation of capsular polysaccharide (CPS) locus genes. Experiments using conditioned media showed that sugar depletion occurred only when the bacterial and epithelial cells were cocultured. CPS depletion occurred whenC. jejuniorganisms were exposed to conditioned media from a differentC. jejunistrain but not when exposed to conditioned media from other bacterial species. Proteinase K or heat treatment of conditioned media under coculture conditions abrogated the effect on the sugars, as did formaldehyde fixation and cycloheximide treatment of host cells or chloramphenicol treatment of the bacteria. However, sugar depletion was not affected in flagellar export (fliQ) and quorum-sensing (luxS) gene mutants. PassagedC. jejunishowed reduced invasiveness and increased serum sensitivity in vitro.C. jejunialters its surface polysaccharides when cocultured with epithelial cells, suggesting the existence of a cross talk mechanism that modulates CPS expression during infection.
Trypanosoma cruziGP63 Proteins Undergo Stage-Specific Differential Posttranslational Modification and Are Important for Host Cell Infection
Authors: Kulkarni Manjusha M. , Olson Cheryl L. , Engman David M. , McGwire Bradford S. 
Published: March 2009

ABSTRACTThe protozoanTrypanosoma cruziexpresses multiple isoforms of the GP63 family of metalloproteases. Polyclonal antiserum against recombinant GP63 ofT. cruzi(TcGP63) was used to study TcGP63 expression and localization in this organism. Western blot analysis revealed that TcGP63 is 61 kDa in epimastigotes, amastigotes, and tissue culture-derived trypomastigotes but 55 kDa in metacyclic trypomastigotes. Antiserum specific forLeishmania amazonensisGP63 specifically reacted with a 55-kDa TcGP63 form in metacyclic trypomastigotes, suggesting stage-specific expression of different isoforms. Surface biotinylation and endoglycosidase digestion experiments showed that TcGP63 is an ecto-glycoprotein in epimastigotes but is intracellular and lacking in N-linked glycans in metacyclic trypomastigotes. Immunofluorescence microscopy showed that TcGP63 is localized on the surfaces of epimastigotes but distributed intracellularly in metacyclic trypomastigotes. TcGP63 is soluble in cold Triton X-100, in contrast toLeishmaniaGP63, which is detergent resistant in this medium, suggesting that GP63 is not raft associated inT. cruzi. Western blot comparison of our antiserum to a previously described anti-peptide TcGP63 antiserum indicates that each antiserum recognizes distinct TcGP63 proteins. Preincubation of trypomastigotes with either TcGP63 antiserum or a purified TcGP63 C-terminal subfragment reduced infection of host myoblasts. These results show that TcGP63 is expressed at all life stages and that individual isoforms play a role in host cell infection.
Anomaly-based bug prediction, isolation, and validation
Authors: Dimitrov Martin , Zhou Huiyang 
Published: March 2009

Software defects, commonly known as bugs, present a serious challenge for system reliability and dependability. Once a program failure is observed, the debugging activities to locate the defects are typically nontrivial and time consuming. In this paper, we propose a novel automated approach to pin-point the root-causes of software failures.
Our proposed approach consists of three steps. The first step is bug prediction, which leverages the existing work on anomaly-based bug detection as exceptional behavior during program execution has been shown to frequently point to the root cause of a software failure. The second step is bug isolation, which eliminates false-positive bug predictions by checking whether the dynamic forward slices of bug predictions lead to the observed program failure. The last step is bug validation, in which the isolated anomalies are validated by dynamically nullifying their effects and observing if the program still fails. The whole bug prediction, isolation and validation process is fully automated and can be implemented with efficient architectural support. Our experiments with 6 programs and 7 bugs, including a real bug in the gcc 2.95.2 compiler, show that our approach is highly effective at isolating only the relevant anomalies. Compared to state-of-art debugging techniques, our proposed approach pinpoints the defect locations more accurately and presents the user with a much smaller code set to analyze.
Commutativity analysis for software parallelization
Authors: Aleen Farhana , Clark Nathan 
Published: March 2009

Extracting performance from many-core architectures requires software engineers to create multi-threaded applications, which significantly complicates the already daunting task of software development. One solution to this problem is automatic compile-time parallelization, which can ease the burden on software developers in many situations. Clearly, automatic parallelization in its present form is not suitable for many application domains and new compiler analyses are needed address its shortcomings.
In this paper, we present one such analysis: a new approach for detecting commutative functions. Commutative functions are sections of code that can be executed in any order without affecting the outcome of the application, e.g., inserting elements into a set. Previous research on this topic had one significant limitation, in that the results of a commutative functions must produce identical memory layouts. This prevented previous techniques from detecting functions like malloc, which may return different pointers depending on the order in which it is called, but these differing results do not affect the overall output of the application. Our new commutativity analysis correctly identify these situations to better facilitate automatic parallelization. We demonstrate that this analysis can automatically extract significant amounts of parallelism from many applications, and where it is ineffective it can provide software developers a useful list of functions that may be commutative provided semantic program changes that are not automatable.
TwinDrivers
Authors: Menon Aravind , Schubert Simon , Zwaenepoel Willy 
Published: March 2009

In a virtualized environment, device drivers are often run inside a virtual machine (VM) rather than in the hypervisor, for reasons of safety and reduction in software engineering effort. Unfortunately, this approach results in poor performance for I/O-intensive devices such as network cards. The alternative approach of running device drivers directly in the hypervisor yields better performance, but results in the loss of safety guarantees for the hypervisor and incurs additional software engineering costs.
In this paper we present TwinDrivers, a framework which allows us to semi-automatically create safe and efficient hypervisor drivers from guest OS drivers. The hypervisor driver runs directly in the hypervisor, but its data resides completely in the driver VM address space. A Software Virtual Memory mechanism allows the driver to access its VM data efficiently from the hypervisor running in any guest context, and also protects the hypervisor from invalid memory accesses from the driver. An upcall mechanism allows the hypervisor to largely reuse the driver support infrastructure present in the VM. The TwinDriver system thus combines most of the performance benefits of hypervisor-based driver approaches with the safety and software engineering benefits of VM-based driver approaches.
Using the TwinDrivers hypervisor driver, we are able to improve the guest domain networking throughput in Xen by a factor of 2.4 for transmit workloads, and 2.1 for receive workloads, both in CPU-scaled units, and achieve close to 64-67 of native Linux throughput.
Phantom-BTB
Authors: Burcea Ioana , Moshovos Andreas 
Published: March 2009

Modern processors use branch target buffers (BTBs) to predict the target address of branches such that they can fetch ahead in the instruction stream increasing concurrency and performance. Ideally, BTBs would be sufficiently large to capture the entire working set of the application and sufficiently small for fast access and practical on-chip dedicated storage. Depending on the application, these requirements are at odds.
This work introduces a BTB design that accommodates large instruction footprints without dedicating expensive onchip resources. In the proposed Phantom-BTB (PBTB) design, a conventional BTB is augmented with a virtual table that collects branch target information as the application runs. The virtual table does not have fixed dedicated storage. Instead, it is transparently allocated, on demand, in the on-chip caches, at cache line granularity. The entries in the virtual table are proactively prefetched and installed in the dedicated conventional BTB, thus, increasing its perceived capacity. Experimental results with commercial workloads under full-system simulation demonstrate that PBTB improves IPC performance over a 1K-entry BTB by 6.9% on average and up to 12.7%, with a storage overhead of only 8%. Overall, the virtualized design performs within 1% of a conventional 4K-entry, single-cycle access BTB, while the dedicated storage is 3.6 times smaller.
Cloning-free regulated monitoring of reporter and gene expression
Authors: al-Haj Latifa , Al-Ahmadi Wijdan , Al-Saif Maher , Demirkaya Omer , Khabar Khalid SA 
Published: March 2009

Abstract

Background
The majority of the promoters, their regulatory elements, and their variations in the human genome remain unknown. Reporter gene technology for transcriptional activity is a widely used tool for the study of promoter structure, gene regulation, and signaling pathways. Construction of transcriptional reporter vectors, including use of cis-acting sequences, requires cloning and time-demanding manipulations, particularly with introduced mutations.

Results
In this report, we describe a cloning-free strategy to generate transcriptionally-controllable linear reporter constructs. This approach was applied in common transcriptional models of inflammatory response and the interferon system. In addition, it was used to delineate minimal transcriptional activity of selected ribosomal protein promoters. The approach was tested for conversion of genes into TetO-inducible/repressible expression cassettes.

Conclusion
The simple introduction and tuning of any transcriptional control in the linear DNA product renders promoter activation and regulated gene studies simple and versatile.
Operating theatre related syncope in medical students: a cross sectional study
Authors: Jamjoom AAB , Nikkar-Esfahani A , Fitzgerald JEF 
Published: March 2009

Abstract

Background
Observing surgical procedures is a beneficial educational experience for medical students during their surgical placements. Anecdotal evidence suggests that operating theatre related syncope may have detrimental effects on students' views of this. Our study examines the frequency and causes of such syncope, together with effects on career intentions, and practical steps to avoid its occurrence.

Methods
All penultimate and final year students at a large UK medical school were surveyed using the University IT system supplemented by personal approach. A 20-item anonymous questionnaire was distributed and results were analysed using the Statistical Package for Social Sciences, version 15.0 (Chicago, Illinois, USA).

Results
Of the 630 clinical students surveyed, 77 responded with details of at least one near or actual operating theatre syncope (12%). A statistically significant gender difference existed for syncopal/near-syncopal episodes (male 12%; female 88%), p < 0.05. Twenty-two percent of those affected were graduate entry medical course students with the remaining 78% undergraduate. Mean age was 23-years (range 20 – 45). Of the 77 reactors, 44 (57%) reported an intention to pursue a surgical career. Of this group, 7 (9%) reported being discouraged by syncopal episodes in the operating theatre. The most prevalent contributory factors were reported as hot temperature (n = 61, 79%), prolonged standing (n = 56, 73%), wearing a surgical mask (n = 36, 47%) and the smell of diathermy (n = 18, 23%). The most frequently reported measures that students found helpful in reducing the occurrence of syncopal episodes were eating and drinking prior to attending theatre (n = 47, 61%), and moving their legs whilst standing (n = 14, 18%).

Conclusion
Our study shows that operating theatre related syncope among medical students is common, and we establish useful risk factors and practical steps that have been used to prevent its occurrence. Our study also highlights the detrimental effect of this on the career intentions of medical students interested in surgery. Based on these findings, we recommend that dedicated time should be set aside in surgical teaching to address this issue prior to students attending the operating theatre.
δ-Catenin promotes prostate cancer cell growth and progression by altering cell cycle and survival gene profiles
Authors: Zeng Yan , Abdallah Agustin , Lu Jian-Ping , Wang Tao , Chen Yan-Hua , Terrian David M , Kim Kwonseop , Lu Qun 
Published: March 2009

Abstract

Background
δ-Catenin is a unique member of β-catenin/armadillo domain superfamily proteins and its primary expression is restricted to the brain. However, δ-catenin is upregulated in human prostatic adenocarcinomas, although the effects of δ-catenin overexpression in prostate cancer are unclear. We hypothesized that δ-catenin plays a direct role in prostate cancer progression by altering gene profiles of cell cycle regulation and cell survival.

Results
We employed gene transfection and small interfering RNA to demonstrate that increased δ-catenin expression promoted, whereas its knockdown suppressed prostate cancer cell viability. δ-Catenin promoted prostate cancer cell colony formation in soft agar as well as tumor xenograft growth in nude mice. Deletion of either the amino-terminal or carboxyl-terminal sequences outside the armadillo domains abolished the tumor promoting effects of δ-catenin. Quantitative RT2 Profiler™ PCR Arrays demonstrated gene alterations involved in cell cycle and survival regulation. δ-Catenin overexpression upregulated cyclin D1 and cdc34, increased phosphorylated histone-H3, and promoted the entry of mitosis. In addition, δ-catenin overexpression resulted in increased expression of cell survival genes Bcl-2 and survivin while reducing the cell cycle inhibitor p21Cip1.

Conclusion
Taken together, our studies suggest that at least one consequence of an increased expression of δ-catenin in human prostate cancer is the alteration of cell cycle and survival gene profiles, thereby promoting tumor progression.
Factor structure and internal consistency of the 12-item General Health Questionnaire (GHQ-12) and the Subjective Vitality Scale (VS), and the relationship between them: a study from France
Authors: Salama-Younes Mareï , Montazeri Ali , Ismaïl Amany , Roncin Charles 
Published: March 2009

Abstract

Background
The objectives of this study were to test the factor structure and internal consistency of the 12-item General Health Questionnaire (GHQ-12) and the Subjective Vitality Scale (VS) in elderly French people, and to test the relationship between these two questionnaires.

Methods
Using a standard 'forward-backward' translation procedure, the English language versions of the two instruments (i.e. the 12-item General Health Questionnaire and the Subjective Vitality Scale) were translated into French. A sample of adults aged 58–72 years then completed both questionnaires. Internal consistency was assessed by Cronbach's alpha coefficient. The factor structures of the two instruments were extracted by confirmatory factor analysis (CFA). Finally, the relationship between the two instruments was assessed by correlation analysis.

Results
In all, 217 elderly adults participated in the study. The mean age of the respondents was 61.7 (SD = 6.2) years. The mean GHQ-12 score was 17.4 (SD = 8.0), and analysis showed satisfactory internal consistency (Cronbach's alpha coefficient = 0.78). The mean VS score was 22.4 (SD = 7.4) and its internal consistency was found to be good (Cronbach's alpha coefficient = 0.83). While CFA showed that the VS was uni-dimensional, analysis for the GHQ-12 demonstrated a good fit not only to the two-factor model (positive vs. negative items) but also to a three-factor model. As expected, there was a strong and significant negative correlation between the GHQ-12 and the VS (r = -0.71, P < 0.001).

Conclusion
The results showed that the French versions of the 12-item General Health Questionnaire (GHQ-12) and the Subjective Vitality Scale (VS) are reliable measures of psychological distress and vitality. They also confirm a significant negative correlation between these two instruments, lending support to their convergent validity in an elderly French population. The findings indicate that both measures have good structural characteristics.
Risk factors of earthquake inpatient death: a case control study
Authors: Wen Jin , Shi YingKang , Li YouPing , Wang Li , Cheng Lan , Gao Zhan , Li Ling 
Published: March 2009

Abstract
Introduction
At 2:28 p.m. on 12 May, 2008, a devastating earthquake measuring 8.0 on the Richter scale hit Wenchuan County, Sichuan Province in southwest China, and resulted in the deaths of thousands of people. To date, few epidemiological studies have been conducted on the determinants of the mortality of patients hospitalised after an earthquake. This paper is aimed at identifying the contributing factors of mortality and providing a clinical reference for the management of those injured in earthquakes.

Methods
A hospital-based case-control study was conducted. Cases included all deaths (n = 36) due to earthquake injuries in the West China Hospital. Controls were the quake survivors from the same hospital by at a ratio of four survivors to one death matched for sex and age. Data sources included death certificates and medical records. A conditional logistic regression was performed to assess the odds ratio (OR) of variables used in the study. A chi-squared test for trend was performed to reveal the possible relations between risk factor (variable) number and case fatality.

Results
People with a severe traumatic brain injury (TBI) had the greatest risk of death (adjusted OR = 253.3, 95% confidence interval (CI) = 8.9 to 7208.6), followed by patients with multiple system organ failure (MSOF; adjusted OR = 87.8, 95% CI = 3.9 to 1928.3). Prior major disease and infection significantly increased the risk of earthquake-related death (adjusted OR = 14.9, 95% CI = 1.9 to 119.0; adjusted OR = 13.7, 95% CI = 1.8 to 103.7; respectively). The number of fatal cases increased as the risk factor numbers also increased.

Conclusions
Severe TBI, infection, MSOF and prior major disease are the significant determinants of earthquake-related inpatient death in the 2008 Wenchuan earthquake. Future research with a large sample size including macro- and micro-level factors is needed.
Patients With Initially Unresectable Colorectal Liver Metastases: Is There a Possibility of Cure?
Authors: Adam René , Wicherts Dennis A. , de Haas Robbert J. , Ciacio Oriana , Lévi Francis , Paule Bernard , Ducreux Michel , Azoulay Daniel , Bismuth Henri , Castaing Denis 
Published: March 2009

Purpose Although oncosurgical strategies have demonstrated increased survival in patients with unresectable colorectal liver metastases (CLM), their potential for cure is still questioned. The aim of this study was to evaluate long-term outcome after combining downsizing chemotherapy and rescue surgery and to define prognostic factors of cure. Patients and Methods All patients with initially unresectable CLM who underwent rescue surgery and had a minimum follow-up of 5 years were included. Cure was defined as a disease-free interval ≥ 5 years from last hepatic or extrahepatic resection until last follow-up. Results Mean age of 184 patients who underwent resection (April 1988 through July 2002) was 56.9 years. Patients had a mean number of 5.3 metastases (bilobar in 76%), associated to extrahepatic disease in 27%. Surgery was possible after one (74%) or more (26%) lines of chemotherapy. Five- and 10-year overall survival rates were 33% and 27%, respectively. Of 148 patients with a follow-up ≥ 5 years, 24 patients (16%) were considered cured (mean follow-up, 118.6 months), six (25%) of whom were considered cured after repeat resection of recurrence. Twelve “cured” patients (50%) had a disease-free interval more than 10 years. Cured patients more often had three or fewer metastases less than 30 mm (P = .03) responding to first-line chemotherapy (P = .05). Multivariate analysis identified maximum size of metastases less than 30 mm at diagnosis, number of metastases at hepatectomy three or fewer, and complete pathologic response as independent predictors of cure. Conclusion Cure can be achieved overall in 16% of patients with initially unresectable CLM resected after downsizing chemotherapy. In addition to increased survival, this oncosurgical approach has real potential for disease eradication.