bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction in Immersive Virtual Environments: Rotating Objects with an Instrumented Prop
Authors: Ruddle Roy A. , Huddart Stewart A. , Jones Dylan M
Published: January 2012

An instrumented prop was used to rotate a virtual object in an immersive virtual environment. For each experimental trial, two virtual objects were displayed adjacent to each other. With an emphasis placed on speed and accuracy, participants rotated one object until its orientation matched the orientation of the other object. Participants used an efficient path of rotation more often when the axes of the object, the participant, and the shortest path of rotation were aligned. In relative terms, these paths were more efficient when there was a large angular difference between the objects' orientations. The rate at which participants rotated the virtual object increased substantially with the magnitude of the initial angular difference between the two orientations. By contrast, in most mental rotation studies the rate of rotation remained constant for variations in angular disparity.
Quantifying Scene Movement with ‘Spatial Velocity’ and its Effects on Cybersickness
Authors: Lo W. T. , So Richard H. Y.
Published: January 2012

Viewing wide field-of-view scene movement with a Virtual Reality (VR) display can cause symptoms of cybersickness (e.g., nausea and headache). It has been known that cybersickness is a type of vection-induced motion sickness. Since vection is associated with the perception of moving scene, two studies have been conducted to investigate the effects of different scene movements on levels of cybersickness. The velocity and complexity of the scene movements were quantified by a previously reported metric called ‘spatial velocity (SV)’ while the levels of cybersickness were measured in terms of nausea ratings and Simulator Sickness Questionnaire (SSQ) scores. Results showed that in both experiments, both the nausea ratings and the SSQ total sickness scores increased significantly with increasing SV in the dominant axes of scene movement. Potential uses of the SV metric for formulating a CyberSickness Dose Value (CSDV) are discussed.
Legibility Threshold Contrast of Uppercase Text Seen against a Dark Background
Authors: Schnell Thomas , Zwahlen Helmut T.
Published: January 2012

A laboratory experiment was conducted to determine the effects of letter height, letter width-to-height ratio, stroke width-to-height ratio, inter-character spacing-to-height ratio, on the legibility of uppercase single words displayed in an achromatic, positive contrast polarity. Legibility was investigated in terms of threshold contrast. A total of 10 young, healthy subjects participated in the experiment which was conducted under carefully controlled conditions in a dark tunnel. A substantial amount of legibility optimization research on individual typographical parameters is found in the technical literature. However, no studies were located that simultaneously investigated the letter-height, the width/height ratio, the stroke-width/height ratio, and the spacing/height ratio in a full factorial experiment such as the one presented in this paper. The presented data can be used to optimize the legibility of uppercase, single words made up by the standard highway alphabet subject to sign size constraints.
Friend-Foe Discrimination, Caffeine, and Sentry Duty
Authors: Johnson Richard F. , Merullo Donna J.
Published: January 2012

In war, the sentry must continually and rapidly detect targets, correctly discriminate friend from foe, and shoot with accuracy. Past research shows that caffeine enhances the sentry's target detection speed when all targets are foes. This study evaluates sentry performance when friend-foe discrimination is required. Eleven men and 11 women participated in four simulated sentry duty sessions lasting 3 hours each: (a) 200 mg caffeine, foe-only; (b) 200 mg caffeine, friend-foe; (c) placebo, foe-only; and (d) placebo, friend-foe. Participants monitored the target scene of the Weaponeer Rifle Marksmanship Simulator with instructions to fire at enemy targets. Without impairing marksmanship, 200 mg caffeine reduced friend-foe discrimination errors and eliminated the decrement in target detection speed associated with time on the task. Men were likely to commit friendly-fire errors (shoot at friendly targets) and women were likely to commit fail-to-fire errors (fail to shoot at enemy targets).
Effects of Cognitive Style, Task Type, and Emergent Features on Display Effectiveness
Authors: Confer Scott M. , Hollands J. G.
Published: January 2012

The purpose of this investigation was to determine the effects of a person's cognitive style and the presence of emergent features in displays on performance in information integration and focused attention tasks. Cognitive style was assessed using Kagan's Matching Familiar Figures Test and performance was measured for each task type. It was predicted that when task demands required the observer to integrate information from different display locations (integrated task), impulsives would perform better than reflectives. Conversely, when the observer had to attend to single elements (focused task), reflectives would be better than impulsives. The display configured with an emergent feature was hypothesized to produce fewer errors and shorter response times for both focused and integrated tasks. Results showed that both tasks were aided by the configural design, eliciting shorter response times, and that this was true regardless of cognitive style. Implications of the results for display design are discussed.
Visibility of Rectangular Targets as a Function of Length and Width
Authors: Schnell Thomas , Zwahlen Helmut T.
Published: January 2012

The human threshold contrast of circular targets has been thoroughly studied by Blackwell and his data has been used in a number of visibility prediction models. These models either assumed the difference in visibility between circular and non-circular targets to be negligible or they used some form of a target shape conversion method. The present research is an effort to quantify the effects of the target aspect-ratio (shorter dimension to longer dimension) on the human threshold contrast. Threshold contrast data from two published target detection studies were combined with data from a small laboratory experiment conducted at Ohio University using a regression model (adjusted R2=0.991). The results clearly suggest that small aspect-ratios should be used if, for a given target area, the rectangular target visibility must be maximized. Applications of this research may include retro-reflective conspicuity markings used for improved nighttime visibility of pedestrians and vehicles or reflectorized posts of crossbucks at passive railroad crossings.
Immunologic Effectiveness of Maraviroc- and Raltegravir-Containing Regimens (R+M+) versus Raltegravir-Based Regimens That Do Not Include Maraviroc (R+M−)
Authors: Antoniou Tony , Smith Graham , Su DeSheng , Raboud Janet M. , Lee Derek , Kovacs Colin , Brunetta Jason , Fletcher David , Crouzat Fred , Loutfy Mona
Published: January 2012

Objective: To compare the immunologic effectiveness of raltegravir–maraviroc (R+M+)-based regimens with raltegravir-based regimens that do not include maraviroc (R+M−) in treatment-experienced patients in clinical practice. Methods: We conducted a retrospective study of treatment-experienced HIV-infected adults receiving either R+M+- or R+M−-based therapy. Longitudinal CD4 counts were analyzed using a linear mixed model. Results: One hundred and fifty-six patients were included in the analysis, of whom 32 were receiving R+M+ and 124 R+M−. Mean baseline CD4 counts in patients on R+M+ and R+M− were 463.8 and 442.3 cells/mm3, respectively ( P = .67). In multivariable mixed models, a baseline viral load ≥50 copies/mL was significantly associated with CD4 change during follow-up ( P < .0001). No difference between R+M+ and R+M− was observed during follow-up ( P = .81). Conclusion: CD4 cell recovery was similar among patients receiving either R+M+- or R+M−-based therapy during a 24-month period of follow-up.
Preferences for Rapid Point-of-Care HIV Testing in Primary Care
Authors: Schwandt Michael , Nicolle Eileen , Dunn Sheila
Published: January 2012

Although the identification of individuals infected with HIV is an important element of treatment and prevention programs, many people living with HIV are unaware of their status. Thus, individuals are unable to benefit from treatment, and preventable HIV transmission continues to occur. Rapid point-of-care testing for HIV has been found to be preferred by patients in some contexts. However, few studies have examined preferences in primary care populations. This study investigates HIV testing preferences within an urban primary care clinic. Employing a cross-sectional design, data were collected on demographic characteristics, HIV risk factors, and testing history and preferences of participants. A total of 81% of participants stated that they would prefer rapid testing to standard testing, a finding that is consistent across demographic variables and risk factors examined. Increased availability of this modality may decrease barriers to HIV testing, with positive implications both for clinical management of HIV infection and prevention of HIV transmission.
Factors Influencing Adherence to ART
Authors: Anuradha S. , Joshi Anant , Negi Madhubala , Nischal Neeraj , Rajeshwari K. , Dewan Richa
Published: January 2012

Background:

Adherence to therapy is central to the success of antiretroviral treatment (ART). With the availability of free ART under the national program in India, cost of ART is no longer the primary determinant of adherence. This study evaluated the adherence and factors influencing it among patients receiving free ART in a public health ART center in India.

Methods:

The adherence and its influences among 250 HIV-positive patients on first line ART for at least 3 months from the ART Center of Maulana Azad Medical College and Lok Nayak Hospital, New Delhi, India were analyzed. The adherence was assessed by patients' self report using the adult AIDS Clinical Trial Group (ACTG) questionnaire and counter checked with pharmacy records. The association of various parameters affecting adherence levels was analyzed by using SPSS package and Epiinfo software.

Results:

Of the 250 patients, 242 (96.8%) had optimum adherence (>95%) and 8 (3.2%) were “non-adherent.” CD4 counts ( P = 0.05), high level of belief among patients, patients' knowledge about importance of adherence ( P = 0.04), and sound mental health were positively influencing adherence. The main barriers to adherence were poor mental health and negative psychological states in the patients (0.001). The presence of adverse reactions to ART also resulted in poorer adherence.

Conclusions:

The modifiable factors most strongly associated with good adherence rates were higher current CD4 counts, patients' beliefs in ART, and positive mental health. These factors can be targeted by simple, practical interventions to improve and maintain high adherence levels.
Vitamin D Insufficiency and Deficiency among HIV-1-Infected Patients in a Tropical Setting
Authors: Wiboonchutikul Surasak , Sungkanuparph Somnuek , Kiertiburanakul Sasisopin , Chailurkit La-or , Charoenyingwattana Angkana , Wangsomboonsiri Wittaya , Chantratita Wasun , Ongphiphadhanakul Boonsong
Published: January 2012

Vitamin D plays role in bone health and the regulation of the immune system. A cross-sectional study of serum 25-hydroxyvitamin D (25[OH]D) levels was conducted among HIV-1-infected Thai patients to determine the prevalence and associated factors of low vitamin D levels (25[OH]D <30 ng/mL) in tropical setting. 25-Hydroxyvitamin D was measured by liquid chromatography/tandem mass spectrometry. Of 178 patients, 58% received antiretroviral therapy at median (interquartile range [IQR]) duration of 7.4 (5.9-8.5) years. The prevalence of 25(OH)D deficiency (<20 ng/mL) and insufficiency (20-29.9 ng/mL) was 26.8% and 44.9%, respectively. Multivariate analysis showed that receiving efavirenz (EFV) was significantly associated with low vitamin D status (odds ratio = 3.60; 95% confidence interval, 1.06-12.15, P <.05). The mean (±standard deviation) level of 25(OH)D in patients receiving and not receiving EFV was 22.9 (6.6) and 28.6 (10.7) ng/mL, respectively, ( P <.05). Low vitamin D status is common and needs to be assessed among HIV-infected patients including tropical residents especially when EFV is used.
Human Performance Consequences of Automated Decision Aids
Authors: Manzey Dietrich , Reichenbach Juliane , Onnasch Linda
Published: January 2012

Two experiments are reported that investigate to what extent performance consequences of automated aids are dependent on the distribution of functions between human and automation and on the experience an operator has with an aid. In the first experiment, performance consequences of three automated aids for the support of a supervisory control task were compared. Aids differed in degree of automation (DOA). Compared with a manual control condition, primary and secondary task performance improved and subjective workload decreased with automation support, with effects dependent on DOA. Performance costs include return-to-manual performance issues that emerged for the most highly automated aid and effects of complacency and automation bias, respectively, which emerged independent of DOA. The second experiment specifically addresses how automation bias develops over time and how this development is affected by prior experience with the system. Results show that automation failures entail stronger effects than positive experience (reliably working aid). Furthermore, results suggest that commission errors in interaction with automated aids can depend on three sorts of automation bias effects: (a) withdrawal of attention in terms of incomplete cross-checking of information, (b) active discounting of contradictory system information, and (c) inattentive processing of contradictory information analog to a “looking-but-not-seeing” effect.
Key Stakeholders' Perceptions of Effective School Leadership
Authors: Odhiambo George , Hii Amy
Published: January 2012

There has been limited research on how teachers, parents and students perceive effective school leadership in practice. The purpose of this article is to present some of the findings derived from a study of key stakeholders’ perceptions of effective school leadership. Key stakeholders were identified as teachers, students and parents. Data were gathered through semi-structured interviews with key stakeholders from one large girl’s school in Sydney, Australia. This research relied largely upon interview responses from teachers, students and parents of one Catholic school. While further insight into the issues may require a longitudinal data that describe perceptions from a substantial number of schools over time, studying one school provided a deeper and detailed understanding of key stakeholders’ perceptions. Findings highlight the complexity of school leadership practices. Key stakeholders’ in this study have also provide us with a useful emphasis on core school leadership dimensions, which they associate with effective school outcomes and improvement. These include administration, responsibility to ensure quality teaching and learning and relational leadership. Stakeholders answers to the question of what makes principals effective and which principal behaviours are most consistent with school effectiveness and improvement provides principals with an important knowledge base for practice.
Cultural influences on the news
Authors: Barker Gina G
Published: January 2012

This study explored how cultural context influences news content by comparing American and Swedish news about the Iraq war in 2003. Using a theoretical foundation derived from the works of Hall (1980, 1997) and Hofstede (1979 , 1980, 1991), a theme analysis of television and print news was conducted. The results revealed that the war was portrayed differently in the two countries and that emphasis was placed on different aspects. American media focused on military strategy, interpreted the war from the troops’ perspective, and explained it as the US bringing freedom to the Iraqi people. Swedish media interpreted the war from the international community’s and the suffering Iraqi civilians’ points of view and explained it as a failure of the international community. As hypothesized, American media had comparatively more masculine content while Swedish media had comparatively more feminine content. Findings suggest that culture is an important variable that should be considered when studying news production and coverage.
Comparing journalism cultures in Latin America
Authors: Mellado Claudia , Moreira Sonia V , Lagos Claudia , Hernández María E
Published: January 2012

Based on interviews with 300 journalists in Chile, Brazil and Mexico, this article describes similarities and differences in their professional cultures. Two competing conceptual explanations are tested: the dominance of political structures, levels of press freedom and the size and concentration of media ownership vs the predominance of political cultures and political parallelism. Although the study provides some evidence in favour of the second scenario – overall in terms of the institutional roles supported by the journalists – neither of the two explanations can fully account for the differences between the countries. Meanwhile, the epistemological and ethical views of the journalists seem to be trapped in contesting terrains of ambiguity, where organizational, media routines and individual factors override country differences.
Seroepidemiology of Klebsiella pneumoniae colonizing the intestinal tract of healthy chinese and overseas chinese adults in Asian countries
Authors: Lin Yi-Tsung , Siu L Kristopher , Lin Jung-Chung , Chen Te-Li , Tseng Chih-Peng , Yeh Kuo-Ming , Chang Feng-Yee , Fung Chang-Phone
Published: January 2012

Background

Capsular serotypes K1 and K2 of Klebsiella pneumoniae are thought to the major virulence determinants responsible for liver abscess. The intestine is one of the major reservoirs of K. pneumoniae, and epidemiological studies have suggested that the majority of K. pneumoniae infections are preceded by colonization of the gastrointestinal tract. The possibility of fecal-oral transmission in liver abscess has been raised on the basis of molecular typing of isolates. Data on the serotype distribution of K. pneumoniae in stool samples from healthy individuals has not been previously reported. This study investigated the seroepidemiology of K. pneumoniae isolates from the intestinal tract of healthy Chinese in Asian countries. Stool specimens from healthy adult Chinese residents of Taiwan, Japan, Hong Kong, China, Thailand, Malaysia, Singapore, and Vietnam were collected from August 2004 to August 2010 for analysis.

Results

Serotypes K1/K2 accounted for 9.8% of all K. pneumoniae isolates from stools in all countries. There was no significant difference in the prevalence of K1/K2 isolates among the countries excluding Thailand and Vietnam. The antimicrobial susceptibility pattern was nearly the same in K. pneumoniae isolates. The result of pulsed-field gel electrophoresis revealed no major clonal cluster of serotype K1 isolates.

Conclusions

The result showed that Chinese ethnicity itself might be a major factor predisposing to intestinal colonization by serotype K1/K2 K. pneumoniae isolates. The prevalent serotype K1/K2 isolates may partially correspond to the prevalence of K. pneumoniae liver abscess in Asian countries.
Defects in leaf carbohydrate metabolism compromise acclimation to high light and lead to a high chlorophyll fluorescence phenotype in Arabidopsis thaliana
Authors: Schmitz Jessica , Schöttler Mark Aurel , Krueger Stephan , Geimer Stefan , Schneider Anja , Kleine Tatjana , Leister Dario , Bell Kirsten , Flügge Ulf-Ingo , Häusler Rainer E
Published: January 2012

Background

We have studied the impact of carbohydrate-starvation on the acclimation response to high light using Arabidopsis thaliana double mutants strongly impaired in the day- and night path of photoassimilate export from the chloroplast. A complete knock-out mutant of the triose phosphate/phosphate translocator (TPT; tpt-2 mutant) was crossed to mutants defective in (i) starch biosynthesis (adg1-1, pgm1 and pgi1-1; knock-outs of ADP-glucose pyrophosphorylase, plastidial phosphoglucomutase and phosphoglucose isomerase) or (ii) starch mobilization (sex1-3, knock-out of glucan water dikinase) as well as in (iii) maltose export from the chloroplast (mex1-2).

Results

All double mutants were viable and indistinguishable from the wild type when grown under low light conditions, but - except for sex1-3/tpt-2 - developed a high chlorophyll fluorescence (HCF) phenotype and growth retardation when grown in high light. Immunoblots of thylakoid proteins, Blue-Native gel electrophoresis and chlorophyll fluorescence emission analyses at 77 Kelvin with the adg1-1/tpt-2 double mutant revealed that HCF was linked to a specific decrease in plastome-encoded core proteins of both photosystems (with the exception of the PSII component cytochrome b559), whereas nuclear-encoded antennae (LHCs) accumulated normally, but were predominantly not attached to their photosystems. Uncoupled antennae are the major cause for HCF of dark-adapted plants. Feeding of sucrose or glucose to high light-grown adg1-1/tpt-2 plants rescued the HCF- and growth phenotypes. Elevated sugar levels induce the expression of the glucose-6-phosphate/phosphate translocator2 (GPT2), which in principle could compensate for the deficiency in the TPT. A triple mutant with an additional defect in GPT2 (adg1-1/tpt-2/gpt2-1) exhibited an identical rescue of the HCF- and growth phenotype in response to sugar feeding as the adg1-1/tpt-2 double mutant, indicating that this rescue is independent from the sugar-triggered induction of GPT2.

Conclusions

We propose that cytosolic carbohydrate availability modulates acclimation to high light in A. thaliana. It is conceivable that the strong relationship between the chloroplast and nucleus with respect to a co-ordinated expression of photosynthesis genes is modified in carbohydrate-starved plants. Hence carbohydrates may be considered as a novel component involved in chloroplast-to-nucleus retrograde signaling, an aspect that will be addressed in future studies.
TGF-β1 modulates the homeostasis between MMPs and MMP inhibitors through p38 MAPK and ERK1/2 in highly invasive breast cancer cells
Authors: Gomes Luciana R , Terra Letícia F , Wailemann Rosângela AM , Labriola Leticia , Sogayar Mari C
Published: January 2012

Background

Metastasis is the main factor responsible for death in breast cancer patients. Matrix metalloproteinases (MMPs) and their inhibitors, known as tissue inhibitors of MMPs (TIMPs), and the membrane-associated MMP inhibitor (RECK), are essential for the metastatic process. We have previously shown a positive correlation between MMPs and their inhibitors expression during breast cancer progression; however, the molecular mechanisms underlying this coordinate regulation remain unknown. In this report, we investigated whether TGF-β1 could be a common regulator for MMPs, TIMPs and RECK in human breast cancer cell models.

Methods

The mRNA expression levels of TGF-β isoforms and their receptors were analyzed by qRT-PCR in a panel of five human breast cancer cell lines displaying different degrees of invasiveness and metastatic potential. The highly invasive MDA-MB-231 cell line was treated with different concentrations of recombinant TGF-β1 and also with pharmacological inhibitors of p38 MAPK and ERK1/2. The migratory and invasive potential of these treated cells were examined in vitro by transwell assays.

Results

In general, TGF-β2, TβRI and TβRII are over-expressed in more aggressive cells, except for TβRI, which was also highly expressed in ZR-75-1 cells. In addition, TGF-β1-treated MDA-MB-231 cells presented significantly increased mRNA expression of MMP-2, MMP-9, MMP-14, TIMP-2 and RECK. TGF-β1 also increased TIMP-2, MMP-2 and MMP-9 protein levels but downregulated RECK expression. Furthermore, we analyzed the involvement of p38 MAPK and ERK1/2, representing two well established Smad-independent pathways, in the proposed mechanism. Inhibition of p38MAPK blocked TGF-β1-increased mRNA expression of all MMPs and MMP inhibitors analyzed, and prevented TGF-β1 upregulation of TIMP-2 and MMP-2 proteins. Moreover, ERK1/2 inhibition increased RECK and prevented the TGF-β1 induction of pro-MMP-9 and TIMP-2 proteins. TGF-β1-enhanced migration and invasion capacities were blocked by p38MAPK, ERK1/2 and MMP inhibitors.

Conclusion

Altogether, our results support that TGF-β1 modulates the mRNA and protein levels of MMPs (MMP-2 and MMP-9) as much as their inhibitors (TIMP-2 and RECK). Therefore, this cytokine plays a crucial role in breast cancer progression by modulating key elements of ECM homeostasis control. Thus, although the complexity of this signaling network, TGF-β1 still remains a promising target for breast cancer treatment.
Phylogenetic analysis of strains of Orf virus isolated from two outbreaks of the disease in sheep in Greece
Authors: Billinis Charalambos , Mavrogianni Vasia S , Spyrou Vasiliki , Fthenakis George C
Published: January 2012

Background

Although orf is endemic around the world, there are few descriptions of Orf virus strains and comparisons of these strains. We report the sequence and phylogenetic analysis of the partial B2L gene of Orf virus from two outbreaks of the disease in Greece. The first was an outbreak of genital form of the disease in a flock imported from France, whilst the second was an outbreak of the disease in the udder skin of ewes and around the mouth of lambs in an indigenous flock.

Results

Phylogenetic analysis was performed on a part (498 bp) of the B2L gene of 35 Parapoxvirus isolates, including the two Orf virus isolates recovered from each of the two outbreaks in the present study. This analysis revealed that the maximum nucleotide and amino-acid variation amongst Orf virus strains worldwide (n = 33) was 8.1% and 9.6%, respectively. The homology of the nucleotide and amino-acid sequences between the two Greek isolates was 99.0% and 98.8%, respectively. The two Greek isolates clustered only with Orf virus strains.

Conclusions

We suggest that there can be differences between strains based on their geographical origin. However, differences in the origin of strains or in the clinical presentation of the disease may not be associated with their pathogenicity. More work is required to determine if differing clinical presentations are linked to viral strain differences or if other factors, e.g., flock immunity, method of exposure or genetic susceptibility, are more important to determine the clinical presentation of the infection.
Biomechanical evaluation of predictive parameters of progression in adolescent isthmic spondylolisthesis: a computer modeling and simulation study
Authors: Sevrain Amandine , Aubin Carl-Eric , Gharbi Hicham , Wang Xiaoyu , Labelle Hubert
Published: January 2012

Background

Pelvic incidence, sacral slope and slip percentage have been shown to be important predicting factors for assessing the risk of progression of low- and high-grade spondylolisthesis. Biomechanical factors, which affect the stress distribution and the mechanisms involved in the vertebral slippage, may also influence the risk of progression, but they are still not well known. The objective was to biomechanically evaluate how geometric sacral parameters influence shear and normal stress at the lumbosacral junction in spondylolisthesis.

Methods

A finite element model of a low-grade L5-S1 spondylolisthesis was constructed, including the morphology of the spine, pelvis and rib cage based on measurements from biplanar radiographs of a patient. Variations provided on this model aimed to study the effects on low grade spondylolisthesis as well as reproduce high grade spondylolisthesis. Normal and shear stresses at the lumbosacral junction were analyzed under various pelvic incidences, sacral slopes and slip percentages. Their influence on progression risk was statistically analyzed using a one-way analysis of variance.

Results

Stresses were mainly concentrated on the growth plate of S1, on the intervertebral disc of L5-S1, and ahead the sacral dome for low grade spondylolisthesis. For high grade spondylolisthesis, more important compression and shear stresses were seen in the anterior part of the growth plate and disc as compared to the lateral and posterior areas. Stress magnitudes over this area increased with slip percentage, sacral slope and pelvic incidence. Strong correlations were found between pelvic incidence and the resulting compression and shear stresses in the growth plate and intervertebral disc at the L5-S1 junction.

Conclusions

Progression of the slippage is mostly affected by a movement and an increase of stresses at the lumbosacral junction in accordance with spino-pelvic parameters. The statistical results provide evidence that pelvic incidence is a predictive parameter to determine progression in isthmic spondylolisthesis.
Interim-treatment quantitative PET parameters predict progression and death among patients with hodgkin's disease
Authors: Tseng Diane , Rachakonda Leelanand P , Su Zheng , Advani Ranjana , Horning Sandra , Hoppe Richard T , Quon Andrew , Graves Edward E , Loo Billy W , Tran Phuoc T
Published: January 2012

Purpose

We hypothesized that quantitative PET parameters may have predictive value beyond that of traditional clinical factors such as the International Prognostic Score (IPS) among Hodgkin's disease (HD) patients.

Methods

Thirty HD patients treated at presentation or relapse had staging and interim-treatment PET-CT scans. The majority of patients (53%) had stage III-IV disease and 67% had IPS ≥ 2. Interim-treatment scans were performed at a median of 55 days from the staging PET-CT. Chemotherapy regimens used: Stanford V (67%), ABVD (17%), VAMP (10%), or BEACOPP (7%). Hypermetabolic tumor regions were segmented semiautomatically and the metabolic tumor volume (MTV), mean standardized uptake value (SUVmean), maximum SUV (SUVmax) and integrated SUV (iSUV) were recorded. We analyzed whether IPS, absolute value PET parameters or the calculated ratio of interim- to pre-treatment PET parameters were associated with progression free survival (PFS) or overall survival (OS).

Results

Median follow-up of the study group was 50 months. Six of the 30 patients progressed clinically. Absolute value PET parameters from pre-treatment scans were not significant. Absolute value SUVmax from interim-treatment scans was associated with OS as determined by univariate analysis (p < 0.01). All four calculated PET parameters (interim/pre-treatment values) were associated with OS: MTVint/pre (p < 0.01), SUVmeanint/pre (p < 0.05), SUVmaxint/pre (p = 0.01), and iSUVint/pre (p < 0.01). Absolute value SUVmax from interim-treatment scans was associated with PFS (p = 0.01). Three calculated PET parameters (int/pre-treatment values) were associated with PFS: MTVint/pre (p = 0.01), SUVmaxint/pre (p = 0.02) and iSUVint/pre (p = 0.01). IPS was associated with PFS (p < 0.05) and OS (p < 0.01).

Conclusions

Calculated PET metrics may provide predictive information beyond that of traditional clinical factors and may identify patients at high risk of treatment failure early for treatment intensification.
Proteomic analysis of the ventral disc of Giardia lamblia
Authors: Lourenço Daniela , Andrade Iamara da Silva , Terra Letícia Labati , Guimarães Patricia Ramos , Zingali Russolina Benedeta , de Souza Wanderley
Published: January 2012

Background

Giardia lamblia is a multiflagellated protozoan that inhabits the small intestine of vertebrates, causing giardiasis. To colonize the small intestine, the trophozoites form of the parasite remains attached to intestinal epithelial cells by means of cytoskeletal elements that form a structure known as the ventral disc. Previous studies have shown that the ventral disc is made of tubulin and giardins.

Results

To obtain further information on the composition of the ventral disc, we developed a new protocol and evaluated the purity of the isolation by transmission electron microscopy. Using 1D- and 2D-PAGE and mass spectrometry, we identified proteins with functions associated with the disc. In addition to finding tubulin and giardin, proteins known to be associated with the ventral disc, we also identified proteins annotated in the Giardia genome, but whose function was previously unknown.

Conclusions

The isolation of the ventral disc shown in this work, compared to previously published protocols, proved to be more efficient. Proteomic analysis showed the presence of several proteins whose further characterization may help in the elucidation of the mechanisms involved in the attachment of the protozoan to epithelial cells.
The loci recommended as universal barcodes for plants on the basis of floristic studies may not work with congeneric species as exemplified by DNA barcoding of Dendrobium species
Authors: Singh Hemant Kumar , Parveen Iffat , Raghuvanshi Saurabh , Babbar Shashi B
Published: January 2012

Background

Based on the testing of several loci, predominantly against floristic backgrounds, individual or different combinations of loci have been suggested as possible universal DNA barcodes for plants. The present investigation was undertaken to check the applicability of the recommended locus/loci for congeneric species with Dendrobium species as an illustrative example.

Results

Six loci, matK, rbcL, rpoB, rpoC1, trnH-psbA spacer from the chloroplast genome and ITS, from the nuclear genome, were compared for their amplification, sequencing and species discrimination success rates among multiple accessions of 36 Dendrobium species. The trnH-psbA spacer could not be considered for analysis as good quality sequences were not obtained with its forward primer. Among the tested loci, ITS, recommended by some as a possible barcode for plants, provided 100% species identification. Another locus, matK, also recommended as a universal barcode for plants, resolved 80.56% species. ITS remained the best even when sequences of investigated loci of additional Dendrobium species available on the NCBI GenBank (93, 33, 20, 18 and 17 of ITS, matK, rbcL, rpoB and rpoC1, respectively) were also considered for calculating the percent species resolution capabilities. The species discrimination of various combinations of the loci was also compared based on the 36 investigated species and additional 16 for which sequences of all the five loci were available on GenBank. Two-locus combination of matK+rbcL recommended by the Plant Working Group of Consortium for Barcoding of Life (CBOL) could discriminate 86.11% of 36 species. The species discriminating ability of this barcode was reduced to 80.77% when additional sequences available on NCBI were included in the analysis. Among the recommended combinations, the barcode based on three loci - matK, rpoB and rpoC1- resolved maximum number of species.

Conclusions

Any recommended barcode based on the loci tested so far, is not likely to provide 100% species identification across the plant kingdom and thus is not likely to act as a universal barcode. It appears that barcodes, if based on single or limited locus(i), would be taxa specific as is exemplified by the success of ITS among Dendrobium species, though it may not be suitable for other plants because of the problems that are discussed.
High-level tolerance to triclosan may play a role in Pseudomonas aeruginosa antibiotic resistance in immunocompromised hosts: evidence from outbreak investigation
Authors: D'Arezzo Silvia , Lanini Simone , Puro Vincenzo , Ippolito Giuseppe , Visca Paolo
Published: January 2012

Background and methods

Pseudomonas aeruginosa is a major infectious threat to immunocompromised patients. We recently reported a fatal epidemic of multidrug-resistant P. aeruginosa in an onchoematology unit, linked to massive contamination of a triclosan-based disinfectant. The aim of this study is to evaluate the antimicrobial activity of triclosan and chlorhexidine digluconate against the epidemic strain of P. aeruginosa, to confirm the hypothesis that the soap dispenser acted as a continuous source of the infection during the outbreak, and to explore the potential role of triclosan in increasing the level of resistance to selected antibiotics.

Susceptibility tests and time-kill assays for disinfectans were performed using two commercial formulations containing triclosan and chlorhexidine digluconate, respectively. Antibiotic susceptibility testing was performed by the broth microdilution method.

Findings

The P. aeruginosa epidemic strain exhibited an extremely high level of triclosan resistance (apparent MIC = 2,125 mg/L), while it was markedly susceptible to chlorhexidine digluconate (apparent MIC = 12.5 mg/L). Upon gradual adaptation to triclosan, the epidemic strain survived for a long period (> 120 h) in the presence of 3,400 mg/L (equivalent to 1.6 × MIC) of triclosan, concomitantly increasing the resistance to six antibiotics that are typical substrates of drug efflux pumps of the resistance nodulation division family. This effect was reversed by efflux pump inhibitors.

Conclusions

The epidemic P. aeruginosa strain was resistant to triclosan and its previous exposure to triclosan increases antibiotic resistance, likely through active efflux mechanisms. Since P. aeruginosa can become tolerant to elevated triclosan concentrations, the use of triclosan-based disinfectants should be avoided in those healthcare settings hosting patients at high risk for P. aeruginosa infection.
Heart Failure Is a Clinically and Densitometrically Independent Risk Factor for Osteoporotic Fractures: Population-Based Cohort Study of 45,509 Subjects
Authors: Majumdar Sumit R. , Ezekowitz Justin A. , Lix Lisa M. , Leslie William D.
Published: January 2012

Objective:

The aim of the study was to determine whether heart failure is associated with an increased risk of major osteoporotic fractures that is independent of bone mineral density (BMD).

Methods:

We conducted a population-based cohort study in Manitoba, Canada, by linking a clinical registry of all adults 50 yr of age and older who underwent initial BMD testing from 1998–2009 with administrative databases. We collected osteoporosis risk factors, comorbidities, medications, and BMD results. Validated algorithms identified recent-onset heart failure before the BMD test and new fractures after. The main outcome was time to major osteoporotic fractures (i.e. clinical vertebrae, distal forearm, humerus, and hip), and multivariable proportional hazards models were used for analyses.

Results:

The cohort consisted of 45,509 adults; 1,841 (4%) had recent-onset heart failure. Subjects with heart failure were significantly (P < 0.001) older (74 vs. 66 yr) and had more previous fractures (21 vs. 13%) and lower total hip BMD [T-score, −1.3 (sd 1.3) vs. −0.9 (sd 1.2)] than those without. There were 2703 incident fractures over the 5-yr observation. Overall, 10% of heart failure subjects had incident major fractures compared with 5% of those without [unadjusted hazard ratio (HR), 2.45; 95% confidence interval (CI), 2.11–2.85]. Adjustment for osteoporosis risk factors, comorbidities, and medications attenuated but did not eliminate this association (HR, 1.33; 95% CI, 1.11–1.60), nor did further adjustment for total hip BMD (HR, 1.28; 95% CI, 1.06–1.53).

Conclusions:

Heart failure is associated with a 30% increase in major fractures that is independent of traditional risk factors and BMD, and it also identifies a high-risk population that may benefit from increased screening and treatment for osteoporosis.
Bone bruise, lipohemarthrosis, and joint effusion in CT of non-displaced hip fracture
Authors: Geijer Mats , Dunker Dennis , Collin David , Göthlin Jan H
Published: January 2012

Background

A suspected occult hip fracture after normal radiography is not uncommon in an elderly person after a fall. Despite a lack of robust validation in the literature, computed tomography (CT) is often used as secondary imaging.

Purpose

To assess the frequency and clinical utility of non-cortical skeletal and soft tissue lesions as ancillary fracture signs in CT diagnosis of occult hip fractures.

Material and Methods

All fracture signs (cortical and trabecular fractures, bone bruise, joint effusion, and lipohemarthrosis) were recorded in 231 hip low-energy trauma cases with CT performed after normal or equivocal radiography in two trauma centers.

Results

There were no fracture signs in 110 patients. Twelve of these had a joint effusion. In 121 patients with 46 cervical hip fractures and 75 trochanteric fractures one or more fracture signs were present. Cortical fractures were found in 115 patients. Bone bruise was found in 119 patients, joint effusion in 35, and lipohemarthrosis in 20 patients.

Conclusion

Ancillary signs such as bone bruise and lipohemarthrosis can strengthen and sometimes indicate the diagnosis in CT of occult hip fractures. Joint effusion is a non-specific sign.
Are Routine Ancillary Stains Required to Diagnose Helicobacter Infection in Gastric Biopsy Specimens?
Authors: Hartman Douglas J. , Owens Scott R.
Published: January 2012

Gastric biopsies are often done to evaluate for Helicobacter gastritis. Given the oncogenic association with Helicobacter gastritis and the relative ease of therapy, it is important for pathology departments to identify all positive cases. We describe an institutional quality assurance study of an institutional method for the diagnosis of Helicobacter gastritis. We reviewed 356 gastric biopsy specimens from a 4-week period at 1 institution. Approximately half were evaluated by 4 methods, H&E stain, Giemsa stain, Warthin-Starry stain, and Helicobacter immunostain, while the remainder were stained only with H&E and Helicobacter immunostains. There were 30 cases of Helicobacter gastritis diagnosed; about 83% of cases were diagnosed on the initial H&E-stained slides. Our study highlights a quality assurance study and a head-to head comparison of 4 methods not previously reported and supports the use of ancillary stains at the discretion of the sign-out pathologist.
PRAME (Preferentially Expressed Antigen of Melanoma) Is a Novel Marker for Differentiating Serous Carcinoma From Malignant Mesothelioma
Authors: Brenne Kjersti , Nymoen Dag André , Reich Reuven , Davidson Ben
Published: January 2012

The PRAME (preferentially expressed antigen of melanoma) gene was previously shown to be overexpressed in ovarian/primary peritoneal serous carcinoma compared with malignant mesothelioma using gene expression arrays. The objective of this study was to validate this finding at the messenger RNA (mRNA) and protein levels. Quantitative real-time polymerase chain reaction analysis of 126 müllerian carcinomas and 23 malignant mesotheliomas showed significantly higher PRAME mRNA expression in the former tumor (P < .001; test sensitivity and specificity, 89% and 91%, respectively). PRAME protein was expressed in 41 of 50 müllerian carcinomas and 0 of 30 mesotheliomas using Western blotting (P < .001; test sensitivity and specificity, 82% and 100%, respectively). PRAME levels in müllerian carcinoma were unrelated to survival; however, PRAME protein expression was up-regulated in solid metastases compared with primary carcinoma and effusions (P < .001). Our data confirm that PRAME effectively differentiates müllerian carcinoma from malignant mesothelioma at the mRNA and protein levels, suggesting a role in the diagnostic workup of serosal cancers.
Maternal Asthma Medication Use and the Risk of Selected Birth Defects
Authors: Lin Shao , Munsie Jean Pierre W. , Herdt-Losavio Michele L. , Druschel Charlotte M. , Campbell Kimberly , Browne Marilyn L. , Romitti Paul A. , Olney Richard S. , Bell Erin M. ,   the National Birth Defects Prevention Study
Published: January 2012

OBJECTIVES:

Approximately 4% to 12% of pregnant women have asthma; few studies have examined the effects of maternal asthma medication use on birth defects. We examined whether maternal asthma medication use during early pregnancy increased the risk of selected birth defects.

METHODS:

National Birth Defects Prevention Study data for 2853 infants with 1 or more selected birth defects (diaphragmatic hernia, esophageal atresia, small intestinal atresia, anorectal atresia, neural tube defects, omphalocele, or limb deficiencies) and 6726 unaffected control infants delivered from October 1997 through December 2005 were analyzed. Mothers of cases and controls provided telephone interviews of medication use and additional potential risk factors. Exposure was defined as maternal periconceptional (1 month prior through the third month of pregnancy) asthma medication use (bronchodilator or anti-inflammatory). Associations between maternal periconceptional asthma medication use and individual major birth defects were estimated by using adjusted odds ratios (aOR) and 95% confidence intervals (95%CI).

RESULTS:

No statistically significant associations were observed for maternal periconceptional asthma medication use and most defects studied; however, positive associations were observed between maternal asthma medication use and isolated esophageal atresia (bronchodilator use: aOR = 2.39, 95%CI = 1.23, 4.66), isolated anorectal atresia (anti-inflammatory use: aOR = 2.12, 95%CI = 1.09, 4.12), and omphalocele (bronchodilator and anti-inflammatory use: aOR = 4.13, 95%CI = 1.43, 11.95).

CONCLUSIONS:

Positive associations were observed for anorectal atresia, esophageal atresia, and omphalocele and maternal periconceptional asthma medication use, but not for other defects studied. It is possible that observed associations may be chance findings or may be a result of maternal asthma severity and related hypoxia rather than medication use.
Public Attitudes Regarding the Use of Residual Newborn Screening Specimens for Research
Authors: Botkin Jeffrey R. , Rothwell Erin , Anderson Rebecca , Stark Louisa , Goldenberg Aaron , Lewis Michelle , Burbank Matthew , Wong Bob
Published: January 2012

BACKGROUND AND OBJECTIVES:

Many state newborn screening (NBS) programs retain residual NBS bloodspots after the completion of screening. Potential uses for residual specimens include laboratory quality assurance, biomedical research, and, rarely, forensic applications. Our objective was to evaluate public opinion about the policies and practices relevant to the retention and use of residual bloodspots for biomedical research.

METHODS:

A total of 3855 respondents were recruited using 3 methods: focus groups (n = 157), paper or telephone surveys (n = 1418), and a Knowledge Networks panel (n = 2280). Some participants (n = 1769) viewed a 22-minute movie about the retention and use of residual specimens while other participants were provided only written information about this practice. All participants were surveyed using a 38-item questionnaire.

RESULTS:

A diverse set of participants was recruited. Respondents were very supportive of NBS in general and accepting of the use of residual bloodspots for important research activities. Respondents were evenly divided on the acceptability of NBS without parental permission, but the majority of respondents supported the use of an “opt-in” process for parental permission for residual bloodspot retention and use. Viewing the educational movie was associated with greater support for bloodspot retention and use.

CONCLUSIONS:

Our results show that the general public surveyed here was supportive of NBS and residual sample retention and research use. However, there was a clear preference for an informed permission process for parents regarding these activities. Education about NBS was associated with a higher level of support and may be important to maintain public trust in these important programs.