bluuebunny/crossref_metadata_2025 huggingface dataset:
Correction of frequency drifts induced by gradient heating in 1H spectra using interleaved reference spectroscopy
Authors: Lange Thomas , Zaitsev Maxim , Buechert Martin
Published: February 2011

Purpose:

To evaluate the impact of heating‐induced frequency drifts on single‐voxel spectroscopy and to demonstrate correction strategies based on the interleaved reference scan technique.

Materials and Methods:

Frequency drifts induced by gradient heating are assessed for two clinical 3 Tesla (T) whole body MR systems. The interleaved reference scan (IRS) method is used for correcting these frequency drifts in 1H spectra in vitro and in vivo. For severely drift‐affected spectroscopy experiments, a feedback‐based version of the IRS sequence is proposed, which adds the functionality of a frequency lock to prevent a degradation of the water suppression.

Results:

It is shown that the line widths of the spectral resonances can be largely reduced with the interleaved reference scan method, resulting in considerably improved peak resolution and signal‐to‐noise ratio. The feedback‐based IRS method additionally allows for stable water suppression, even in the presence of very strong frequency drifts.

Conclusion:

If spectroscopy scans are combined with imaging scans with a high gradient duty cycle such as diffusion‐weighted imaging or functional MRI, a drift correction with IRS can considerably improve the validity of data analysis in research studies. J. Magn. Reson. Imaging 2011;33:748–754. © 2011 Wiley‐Liss, Inc.
Early versus late GD‐DTPA MRI enhancement in experimental glioblastomas
Authors: Farace Paolo , Tambalo Stefano , Fiorini Silvia , Merigo Flavia , Daducci Alessandro , Nicolato Elena , Conti Giamaica , Degrassi Anna , Sbarbati Andrea , Marzola Pasquina
Published: February 2011

Purpose:

To compare early versus late enhancement in two glioblastoma models characterized by different infiltrative/edematous patterns.

Materials and Methods:

Three weeks after inoculation into nude mice of U87MG and U251 cells, T1‐weighted images were acquired early (10.5 min), intermediate (21 min) and late (30.5 min) after a bolus injection of Gd‐DTPA at 300 μ mol/kg dosage. EARLYTH and LATETH were the corresponding volumes with an enhancement higher than a threshold TH, defined by the mean (μ) and standard deviation (σ) on a contralateral healthy area. ADDTH was the enhancing volume found in LATETH but not in EARLYTH. T2 imaging of both tumors was performed, and T2 mapping of U251.

Results:

In all tumors, LATETH was significantly higher than EARLYTH for TH ranging from μ+σ to μ+5σ. The ADDTH/EARLYTH ratio was not significantly different when U251 and U87MG tumors were compared. In the U87MG tumors, some enhancement was observed outside the regularly demarcated T2‐hyperintense area. In the U251 tumors, irregularly T2 demarcated, a large portion of ADDμ+3σ had normal T2 values. At histology, U251 showed a higher infiltrative pattern than U87MG.

Conclusion:

In these models, the increase over time in the enhancing volume did not depend on the different infiltrative/edematous patterns and was not closely related with edema. J. Magn. Reson. Imaging 2011;33:550–556. © 2011 Wiley‐Liss, Inc.
Evaluation of hippocampal volume based on MR imaging in patients with bipolar affective disorder applying manual and automatic segmentation techniques
Authors: Doring Thomas M. , Kubo Tadeu T.A. , Cruz L. Celso H. , Juruena Mario F. , Fainberg Jiosef , Domingues Romeu C. , Gasparetto Emerson L.
Published: February 2011

Purpose:

To compare the hippocampal volumes in patients with bipolar disorder (BD) and healthy controls, obtained by applying different segmentation methods (manual, Freesurfer [FS], and FSL).

Materials and Methods:

The study included 27 patients with BD and 40 healthy controls. T1‐weighted images in the sagittal plane were acquired on a 3 Tesla (T) MR scanner. Hippocampal volumetry was performed using one manual and two automated methods (FS and FSL). One‐way repeated analysis of variance was applied to test the differences in hippocampal volumes using the three segmentation methods. To evaluate the agreement among the three tested volumetric segmentation methods the intraclass correlation coefficients (ICCs) were calculated.

Results:

Hippocampal volumes obtained from all methods were significantly different (P < 0.05) in BD patients after intracranial volume correction, indicating a reduction in volume, unless from the manual method of the left hippocampal volume. The ICCs of the hippocampal volume between the manual method and FS were 0.846 (right) and 0.859 (left), and between the manual method and FSL were 0.746 (right) and 0.654 (left).

Conclusion:

Both manual and automatic segmentation methods detected reductions in the hippocampal volumes in BD patients. Automated segmentation methods are a robust and reproducible option for assessing hippocampal volume. J. Magn. Reson. Imaging 2011;33:565–572. © 2011 Wiley‐Liss, Inc.
Delayed contrast enhanced MRI of meniscus with ionic and non‐ionic agents
Authors: Li Wei , Edelman Robert R. , Prasad Pottumarthi V.
Published: February 2011

Purpose:

To evaluate the potential difference in post‐contrast T1 relaxation time of the meniscus (T1Gd) between osteoarthritic patients (OA) and healthy subjects (HS), and to verify if charge density has any influence on meniscal T1Gd.

Materials and Methods:

We performed a retrospective analysis of meniscal T1 relaxation time on data previously acquired for studying articular cartilage with both ionic and non‐ionic contrast media. MR imaging was performed in 10 OA and 8 HS at 120 min following administration of double‐dose ionic Gd‐DTPA2− on one day and non‐ionic Gd‐DTPA‐BMA on a different day. A three‐dimensional Look‐Locker sequence with echo time of 2 ms was used for data acquisition to allow T1 mapping of the meniscus.

Results:

Compared with HS, significantly lower meniscal T1Gd was observed in OA with either ionic Gd‐DTPA2− (P < 0.01) or non‐ionic Gd‐DTPA‐BMA (P < 0.001) contrast agent. There was a correlation between meniscal T1(Gd‐DTPA2−) versus T1(Gd‐DTPA‐BMA). Meniscal T1(Gd‐DTPA‐BMA) showed a larger difference and smaller overlap between OA and HS. No significant differences in either pre‐contrast T1 or post‐contrast T1Gd were observed between inner and outer zones of the meniscus with either agent.

Conclusion:

Significant differences in meniscal T1Gd between OA and HS were observed with both ionic and non‐ionic contrast agents, suggesting that charge density is not responsible for the observed differences. J. Magn. Reson. Imaging 2011;33:731–735. © 2011 Wiley‐Liss, Inc.
Segmentations of MRI images of the female pelvic floor: A study of inter‐ and intra‐reader reliability
Authors: Hoyte Lennox , Ye Wen , Brubaker Linda , Fielding Julia R. , Lockhart Mark E. , Heilbrun Marta E. , Brown Morton B. , Warfield Simon K. ,   for the Pelvic Floor Disorders Network
Published: February 2011

Purpose:

To describe the inter‐ and intra‐operator reliability of segmentations of female pelvic floor structures.

Materials and Methods:

Three segmentation specialists were asked to segment out the female pelvic structures in 20 MR datasets on three separate occasions. The STAPLE algorithm was used to compute inter‐ and intra‐segmenter agreement of each organ in each dataset. STAPLE computed the sensitivity, specificity, and positive predictive values (PPV) for inter‐ and intra‐segmenter repeatability. These parameters were analyzed using intra‐class correlation analysis. Correlation of organ volume to PPV and sensitivity was also computed.

Results:

Mean PPV of the segmented organs ranged from 0.82 to 0.99, and sensitivity ranged from 33 to 96%. Intra‐class correlation ranged from 0.07 to 0.98 across segmenters. Pearson correlation of volume to sensitivity were significant across organs, ranging from 0.54 to 0.91. Organs with significant correlation of PPV to volume were bladder (−0.69), levator ani (−0.68), and coccyx (−0.63).

Conclusion:

Undirected manual segmentation of the pelvic floor organs are adequate for locating the organs, but poor at defining structural boundaries. J. Magn. Reson. Imaging 2011;33:684–691. © 2011 Wiley‐Liss, Inc.
Imaging of blood flow using hyperpolarized [13C]Urea in preclinical cancer models
Authors: von Morze Cornelius , Larson Peder E.Z. , Hu Simon , Keshari Kayvan , Wilson David M. , Ardenkjaer‐Larsen Jan Henrik , Goga Andrei , Bok Robert , Kurhanewicz John , Vigneron Daniel B.
Published: February 2011

Purpose:

To demonstrate dynamic imaging of a diffusible perfusion tracer, hyperpolarized [13C]urea, for regional measurement of blood flow in preclinical cancer models.

Materials and Methods:

A pulse sequence using balanced steady state free precession (bSSFP) was developed, with progressively increasing flip angles for efficient sampling of the hyperpolarized magnetization. This allowed temporal and volumetric imaging of the [13C]urea signal. Regional signal dynamics were quantified for kidneys and liver, and estimates of relative blood flows were derived from the data. Detailed perfusion simulations were performed to validate the methodology.

Results:

Significant differences were observed in the signal patterns between normal and cancerous murine hepatic tissues. In particular, a 19% reduction in mean blood flow was observed in tumors, with 26% elevation in the tumor rim. The blood flow maps were also compared with metabolic imaging results with hyperpolarized [1‐13C]pyruvate.

Conclusion:

Regional assessment of perfusion is possible by imaging of hyperpolarized [13C]urea, which is significant for the imaging of cancer. J. Magn. Reson. Imaging 2011;33:692–697. © 2011 Wiley‐Liss, Inc.
In vivo three‐dimensional MR wall shear stress estimation in ascending aortic dilatation
Authors: Bieging Erik T. , Frydrychowicz Alex , Wentland Andrew , Landgraf Benjamin R. , Johnson Kevin M. , Wieben Oliver , François Christopher J.
Published: February 2011

Purpose:

To estimate surface‐based wall shear stress (WSS) and evaluate flow patterns in ascending aortic dilatation (AscAD) using a high‐resolution, time‐resolved, three‐dimensional (3D), three‐directional velocity encoded, radially undersampled phase contrast MR sequence (4D PC‐MRI).

Materials and Methods:

4D PC‐MRI was performed in 11 patients with AscAD (46.3 ± 22.0 years) and 10 healthy volunteers (32.9 ± 13.4 years) after written informed consent and institutional review board approval. Following manual vessel wall segmentation of the ascending aorta (MATLAB, The Mathworks, Natick, MA), a 3D surface was created using spline interpolation. Spatial WSS variation based on surface division in 12 segments and temporal variation were evaluated in AscAD and normal aortas. Visual analysis of flow patterns was performed based on streamlines and particle traces using EnSight (v9.0, CEI, Apex, NC).

Results:

AscAD was associated with significantly increased diastolic WSS, decreased systolic to diastolic WSS ratio, and delayed onset of peak WSS (all P < 0.001). Temporally averaged WSS was increased and peak systolic WSS was decreased. The maximum WSS in AscAD was on the anterior wall of the ascending aorta. Vortical flow with highest velocities along the anterior wall and increased helical flow during diastole were observed in AscAD compared with controls.

Conclusion:

Changes in WSS in the ascending aorta of AscAD correspond to observed alterations in flow patterns compared to controls. J. Magn. Reson. Imaging 2011;33:589–597. © 2011 Wiley‐Liss, Inc.
Characterization of hyperintense nodules on precontrast T1‐weighted MRI: Utility of gadoxetic acid‐enhanced hepatocyte‐phase imaging
Authors: Chou Chen‐Te , Chen Yao‐Li , Wu Hwa‐Koon , Chen Ran‐Chou
Published: February 2011

Purpose:

To evaluate the utility of gadoxetic acid‐enhanced hepatocyte‐phase magnetic resonance imaging (MRI) in characterization of T1‐weighted hyperintense nodules within cirrhotic liver.

Materials and Methods:

This retrospective study was approved by our Institutional Review Board. Thirty‐four nodules hyperintense in unenhanced T1‐weighted MRI with histopathological confirmation from a collection of 19 patients were included. Tumor size, signal intensity on T1‐weighted, and T2‐weighted imaging as well as enhancement patterns on contrast‐enhanced dynamic/hepatocyte‐phase imaging were recorded. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic performance of hepatocyte‐phase imaging.

Results:

Evaluation of the nodules with standard of reference revealed 15 dysplastic nodules (DN), seven well‐differentiated hepatocellular carcinomas (wHCC), and 12 moderately differentiated HCCs (mHCC). The mean size of dysplastic nodules was smaller than that of HCCs (P < 0.001). Using the HCC criteria (T2W or arterial enhancement followed with portal venous washout), 11/19 HCC were correctly characterized. Using solely hypointensity (compared to the surrounding liver parenchyma) during the hepatocyte phase as the criterion, 18/19 HCC were correctly characterized. There were seven additional HCCs diagnosed with hepatocyte‐phase imaging (P = 0.02).

Conclusion:

Gadoxetic acid‐enhanced MRI with hepatocyte‐phase imaging is superior to gadoxetic acid‐enhanced MRI with conventional criteria alone in characterization of T1W hyperintense nodules. J. Magn. Reson. Imaging 2011;33:625–632. © 2011 Wiley‐Liss, Inc.
Using diffusion tensor imaging and immunofluorescent assay to evaluate the pathology of multiple sclerosis
Authors: Zollinger Lauren V. , Kim Tae Ho , Hill Kenneth , Jeong Eun K. , Rose John W.
Published: February 2011

Purpose:

To determine the ability of the principal diffusion tensor imaging (DTI) indices to predict the underlying histopathology evaluated with immunofluorescent assay (IFA).

Materials and Methods:

Conventional T2 and 3D multishot‐diffusion weighted echoplanar imaging (3D ms‐DWEPI) was performed on a fixed, ex vivo human cervical spinal cord (CSC) from a patient with a history of multiple sclerosis (MS). In all, 170 regions of interest (ROIs) were selected within the white matter and categorized as a high intensity lesion (HIL), low intensity lesion (LIL), and normal‐appearing white matter (NAWM). The longitudinal diffusivity (λl), radial diffusivity (λr), and fractional anisotropy (FA) were obtained from each ROI. The underlying histopathology was then evaluated using immunofluorescent assay with antibodies directed to myelin and neurofilament staining.

Results:

The mean values for λl and λr were significantly elevated within HIL relative to NAWM and LIL. IFA analysis of HIL demonstrated significant demyelination, without significant if any axon loss. The FA values were significantly reduced in HIL and LILs. FA values were also reduced in lesions with increased λl and λr values relative to normal.

Conclusion:

Aberrant λl, λr, and FA relative to normal values are strong indicators of demyelination. DTI indices are not specific for axon loss. IFA analysis is a reliable method to demonstrate myelin and axon pathology within the ex vivo setting. J. Magn. Reson. Imaging 2011;33:557–564. © 2011 Wiley‐Liss, Inc.
MRI in patients with inflammatory bowel disease
Authors: Gee Michael S. , Harisinghani Mukesh G.
Published: February 2011

Inflammatory bowel disease (IBD) affects ≈1.4 million people in North America and, because of its typical early age of onset and episodic disease course, IBD patients often undergo numerous imaging studies over the course of their lifetimes. Computed tomography (CT) has become the standard imaging modality for assessment of IBD patients because of its widespread availability, rapid image acquisition, and ability to evaluate intraluminal and extraluminal disease. However, repetitive CT imaging has been associated with a significant ionizing radiation risk to patients, making MRI an appealing alternative IBD imaging modality. Pelvic MRI is currently the imaging gold standard for detecting perianal disease, while recent studies indicate that MRI bowel‐directed techniques (enteroclysis, enterography, colonography) can accurately evaluate bowel inflammation in IBD. With recent technical innovations leading to faster and higher resolution body MRI, the role of MRI in IBD evaluation is likely to continue to expand. Future applications include surveillance imaging, detection of mural fibrosis, and early assessment of therapy response. J. Magn. Reson. Imaging 2011;33:527–534. © 2011 Wiley‐Liss, Inc.
Genotypes and viral load of hepatitis C virus among persons attending a voluntary counseling and testing center in Ethiopia
Authors: Abreha Tesfay , Woldeamanuel Yimtubezinash , Pietsch Corinna , Maier Melanie , Asrat Daniel , Abebe Almaz , Hailegiorgis Bereket , Aseffa Abraham , Liebert Uwe Gerd
Published: February 2011

The prevalence of different genotypes of hepatitis C virus (HCV) in Ethiopia is not known. HCV genotypes influence the response to therapy with alpha‐interferon alone or in combination with ribavirin. A cross sectional study was conducted on attendees of voluntary counseling and testing center. Serum samples from 1,954 (734 HIV positive and 1,220 HIV negative) individuals were screened for HCV antibody. Active HCV infection was confirmed by quantitative PCR in 18 of the 71 samples with anti‐HCV antibodies. The HCV viral load ranged from 39,650 to 9,878,341 IU/ml (median 1,589,631 IU/ml) with no significant difference [χ2(17) = 18.00, P = 0.389] between persons positive or negative for HIV. The viral load of HCV was, however, higher in older study subjects (r = 0.80, P = 0.000). HCV genotypes were determined using the VERSANT HCV Genotype Assay (LiPA) and sequence analysis of the NS5b region of the HCV genome. Diverse HCV genotypes were found including genotypes 1, 2, 4, and 5. There was no difference in the distribution regarding the HIV status. As in other parts of the world, genotyping of HCV must be considered whenever HCV is incriminated as a cause of hepatitis. J. Med. Virol. 83:776–782, 2011. © 2011 Wiley‐Liss, Inc.
Association of IL28B variants with response to pegylated‐interferon alpha plus ribavirin combination therapy reveals intersubgenotypic differences between genotypes 2a and 2b
Authors: Sakamoto Naoya , Nakagawa Mina , Tanaka Yasuhito , Sekine‐Osajima Yuko , Ueyama Mayumi , Kurosaki Masayuki , Nishida Nao , Tamori Akihiro , Yuki Nishimura‐Sakurai , Itsui Yasuhiro , Azuma Seishin , Kakinuma Sei , Hige Shuhei , Itoh Yoshito , Tanaka Eiji , Hiasa Yoichi , Izumi Namiki , Tokunaga Katsushi , Mizokami Masashi , Watanabe Mamoru ,   the Ochanomizu‐Liver Conference Study Group
Published: February 2011

Genetic polymorphisms of the interleukin 28B (IL28B) locus are associated closely with outcomes of pegylated‐interferon (PEG‐IFN) plus ribavirin (RBV) combination therapy. The aim of this study was to investigate the relationship between IL28B polymorphism and responses to therapy in patients infected with genotype 2. One hundred twenty‐nine chronic hepatitis C patients infected with genotype 2, 77 patients with genotype 2a and 52 patients with genotype 2b, were analyzed. Clinical and laboratory parameters, including genetic variation near the IL28B gene (rs8099917), were assessed. Drug adherence was monitored in each patient. Univariate and multivariate statistical analyses of these parameters and clinical responses were carried out. Univariate analyses showed that a sustained virological response was correlated significantly with IL28B polymorphism, as well as age, white blood cell and neutrophil counts, adherence to RBV, and rapid virological response. Subgroup analysis revealed that patients infected with genotype 2b achieved significantly lower rapid virological response rates than those with genotype 2a. Patients with the IL28B‐major allele showed higher virus clearance rates at each time point than those with the IL28B‐minor allele, and the differences were more profound in patients infected with genotype 2b than those with genotype 2a. Furthermore, both rapid and sustained virological responses were associated significantly with IL28B alleles in patients with genotype 2b. IL28B polymorphism was predictive of PEG‐IFN plus RBV combination treatment outcomes in patients infected with genotype 2 and, especially, with genotype 2b. In conclusion, IL‐28B polymorphism affects responses to PEG‐IFN‐based treatment in difficult‐to‐treat HCV patients. J. Med. Virol. 83:871–878, 2011. © 2011 Wiley‐Liss, Inc.
Hantavirus‐specific IgA in saliva and viral antigen in the parotid gland in patients with hemorrhagic fever with renal syndrome
Authors: Pettersson Lisa , Rasmuson Johan , Andersson Charlotta , Ahlm Clas , Evander Magnus
Published: February 2011

The Hantavirus genus comprises rodent borne, zoonotic viruses of the Bunyaviridae family that cause hemorrhagic fever with renal syndrome (HFRS) in Eurasia and hantavirus cardiopulmonary syndrome (HCPS) in the Americas. Rodent saliva contains infectious hantavirus and evidence suggests that hantavirus is also shed in human saliva, but person‐to‐person transmission is rare. In saliva, immunoglobulin (Ig) A is the predominant immunoglobulin class. Secretory IgA serves as an important first line of defence on epithelial surfaces and the binding of secretory IgA to pathogens can inhibit adherence of microorganisms to mucosal cells and neutralize viruses. This study investigated the presence and importance of salivary IgA in relation to viral antigen in the saliva by testing Puumala hantavirus (PUUV) specific IgA, and RNA in saliva in acutely ill patients with HFRS. In saliva samples, PUUV specific IgA was detected in 12 of 33 (36%) patients with HFRS and 20 (61%) were PUUV RNA positive. There was a statistically significant inverse association between the presence of salivary IgA antibodies and PUUV RNA in the saliva. PUUV‐specific IgA in saliva was not found in a long‐term follow‐up, while PUUV IgA in serum was detected in three patients, 28–32 months after the initial study. Notably, both PUUV RNA and PUUV nucleocapsid antigen were detected in endothelial cells within the parotid gland of a deceased patient with HFRS. J. Med. Virol. 83:864–870, 2011. © 2011 Wiley‐Liss, Inc.
Lithium chloride and staurosporine potentiate the accumulation of phosphorylated glycogen synthase kinase 3β/Tyr216, resulting in glycogen synthase kinase 3β activation in SH‐SY5Y human neuroblastoma cell lines
Authors: Noël Anastasia , Barrier Laurence , Rinaldi Francois , Hubert Claire , Fauconneau Bernard , Ingrand Sabrina
Published: February 2011

Glycogen synthase kinase 3β (GSK3β) activity is regulated by phosphorylation processes and regulates in turn through phosphorylation several proteins, including eukaryotic initiation factor 2B (eIF2B). Serine 9 phosphorylation of GSK3β (pGSK3βSer9), usually promoted by activation of the PI3K/Akt survival pathway, triggers GSK3β inhibition. By contrast, tyrosine 216 phosphorylation of GSK3β (pGSK3βTyr216) increases under apoptotic conditions, leading to GSK3β activation. Lithium chloride (LiCl) is usually described to increase pGSK3βSer9 through the PI3K/Akt pathway, resulting in GSK3β inhibition. The purpose of this study is to demonstrate that in some cases LiCl is also able to increase pGSK3βTyr216, resulting in GSK3β activation. For this, we used SH‐SY5Y cells and primary neuronal cultures and investigated the effects of LiCl on the two phosphorylated forms of GSK3β under staurosporine (STS)‐intoxicated conditions. The ratios between the phosphorylated and total forms of GSK3β and eIF2B were determined by Western blotting. Our results revealed that, besides its ability to increase pGSK3βSer9, LiCl is also able to increase pGSK3βTyr216 greatly in STS‐intoxicated SH‐SY5Y cells but not in STS‐intoxicated primary neuronal cultures. This accumulation of both Ser9 and Tyr216 phosphorylation results in GSK3β activation in STS‐intoxicated SH‐SY5Y cells in spite of the presence of LiCl. These findings indicate that LiCl treatment is not necessarily correlated with GSK3β inhibition even though it generates Ser9 phosphorylation. Consequently, the ratio pGSK3βSer9/pGSK3βTyr216, which takes into account the balance between the two inactive (Ser9) and active (Tyr216) forms of GSK3β, could be more useful for predicting GSK3β inhibition. © 2011 Wiley‐Liss, Inc.
Biomechanical effects of total knee arthroplasty component malrotation: A computational simulation
Authors: Thompson Julie A. , Hast Michael W. , Granger Jeffrey F. , Piazza Stephen J. , Siston Robert A.
Published: February 2011

Modern total knee arthroplasty (TKA) is an effective procedure to treat pain and disability due to osteoarthritis, but some patients experience quadriceps weakness after surgery and have difficulty performing important activities of daily living. The success of TKA depends on many factors, but malalignment of the prosthetic components is a major cause of postoperative complications. Significant variability is associated with femoral and tibial component rotational alignment, but how this variability translates into functional outcome remains unknown. We used a forward‐dynamic computer model of a simulated squatting motion to perform a parametric study of the effects of variations in component rotational alignment in TKA. A cruciate‐retaining and posterior‐stabilized version of the same TKA implant were compared. We found that femoral rotation had a greater effect on quadriceps forces, collateral ligament forces, and varus/valgus kinematics, while tibial rotation had a greater effect on anteroposterior translations. Our findings support the tendency for orthopedic surgeons to bias the femoral component into external rotation and avoid malrotation of the tibial component. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 969–975, 2011
Statistical analysis of bone mineral density using voxel‐based morphometry—an application on proximal sesamoid bones in racehorses
Authors: Shi Lin , Wang Defeng , Riggs Christopher M. , Qin Ling , Griffith James F.
Published: February 2011

Voxel‐based morphometry (VBM) is a computational technique that has been used to analyze statistical differences between groups of MR brain images. This study outlines a new VBM pipeline, designed for determining statistical variation in bone mineral density (BMD). CT images of proximal sesamoid bone (PSB) specimens from the right forelimb of six racehorses that had suffered PSB fractures were compared with six age‐matched control specimens. Following segmentation, masked gray‐scale images were co‐aligned to a statistical template generated with all 12 CT datasets iteratively. Studentt‐tests were performed voxel‐by‐voxel on spatially aligned 3D images to reveal significant differences in the spatial variation of bone density between the fracture and control groups. Overall density and densities from the axial and abaxial areas of PSBs were compared between groups. The BMD in abaxial regions of the medial and lateral PSBs of the fracture group were 12.7% (p = 0.044) and 13.5% (p = 0.047) higher, respectively, than controls. The overall mean density of paired PSB and the medial and lateral PSBs separately were higher in the fracture group. The VBM pipeline facilitates detailed comparison of density variation between bone groups at the voxel level. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1230–1236, 2011
Hip osteoarthritis susceptibility is associated with IL1B −511(G>A) and IL1 RN (VNTR) genotypic polymorphisms in Croatian caucasian population
Authors: Jotanovic Zdravko , Etokebe Godfrey E. , Mihelic Radovan , Heiland Kårvatn Marikken , Mulac‐Jericevic Biserka , Tijanic Tamara , Balen Sanja , Sestan Branko , Dembic Zlatko
Published: February 2011

Among the predisposing factors to osteoarthritis (OA), a frequent destructive joint disease, is the complex genetic heritage including the interleukin‐1 family members like the IL1β (IL1B) and the IL1 receptor antagonist (IL1RN) genes. The aim of this study was to investigate allelic and genotypic frequencies of the IL1B gene single nucleotide polymorphism (SNP) at −511(G>A) and the variable number tandem repeat (VNTR) in the IL1RN gene in a Croatian Caucasian population of hip OA (HOA) cases and healthy controls. A total of 259 HOA patients with total hip replacement (THR) and 518 healthy blood donors as controls were genotyped for IL1B gene SNP −511(G>A) and the VNTR in the IL1RN gene associated with HOA. The genotype G/A (1/2) at IL1B was significantly associated with the protection of the HOA (p < 0.036, OR = 0.72, 95% CI = 0.52–0.99). The genotype G/G (1/1) had only a trend towards the susceptibility (p = 0.053, OR = 1.35, 95% CI = 0.98–1.86) to disease. None of the haplotypes IL1B −511(G>A) and IL1RN (VNTR) were found associated with the HOA. The haplotype 1–2 at these loci had only a trend to susceptibility (p = 0.065). Haplotype 1–3 had a significant male bias in diseased. Furthermore, genotype comprising 2–1/2–2 haplotypes was found significantly associated with predisposition to HOA (p = 0.027, OR = 2.23, 95% CI = 1.03–4.88), whereas genotype 1–1/2–2 with protection to disease (p = 0.028, OR = 0.65, 95% CI = 0.43–0.97). Our findings suggest that HOA in Croatian population might have a different genetic risk regarding the IL1 locus than has been reported for other Caucasian populations previously. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1137–1144, 2011
Depth of subchondral perforation influences the outcome of bone marrow stimulation cartilage repair
Authors: Chen Hongmei , Hoemann Caroline D. , Sun Jun , Chevrier Anik , McKee Marc D. , Shive Matthew S. , Hurtig Mark , Buschmann Michael D.
Published: February 2011

Subchondral drilling and microfracture are bone marrow stimulation techniques commonly used for the treatment of cartilage defects. Few studies to date have examined the technical variants which may influence the success of the cartilage repair procedures. This study compared the effect of hole depth (6 mm vs. 2 mm) and hole type (drill vs. microfracture) on chondral defect repair using a mature rabbit model. Results from quantitative histomorphometry and histological scoring showed that deeper versus shallower drilling elicited a greater fill of the cartilage defect with a more hyaline character in the repair matrix indicated by significant improvement (p = 0.021) in the aggregate measure of increased cartilage defect fill, increased glycosaminoglycan and type II collagen content and reduced type I collagen content of total soft repair tissue. Compared to microfracture at the same 2 mm depth, drilling to 2 mm produced a similar quantity and quality of cartilage repair (p = 0.120) according to the aggregate indicator described above. We conclude that the depth of bone marrow stimulation can exert important influences on cartilage repair outcomes. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1178–1184, 2011
Humeral cementless surface replacement arthroplasties of the shoulder: An experimental investigation on their initial fixation
Authors: Jakubowitz Eike , Neubrech Christine , Raiss Patric , Nadorf Jan , Tanner Michael C. , Rickert Markus , Kasten Philip
Published: February 2011

Cementless surface replacement arthroplasties are increasingly being used to treat arthritic humeral heads. These implants are designed to provide narrow bone resection, making a later revision easier. However, no clear evidence exists as to whether their initial fixation is sufficient for bony ingrowth. The aim of our in vitro study was to characterize the relative micromotion of two resurfacing implants with essentially different bone‐facing geometries. Both systems were implanted into 10 human humeral specimens and micromotion was measured under a cyclic torque application of up to ±1.75 Nm. The mean relative rotary motion resulted in a significant difference (p = 0.036), which was attributed to design differences of central stabilizers featuring both implants. A conversion of rotary motions into relative micromotions, using recently measured moments acting on these implants during daily activities of living, nullified this difference (p = 0.088). However, depending on the shoulder load case considered, a clear difference appeared (p = 0.031–0.045). In conclusion, both resurfacing implants are capable of achieving sufficient initial fixation on the humeral head and perform relative micromotions in a range considered safe for bony ingrowth. Patient‐related parameters do not appear to influence the initial fixation of these implants. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1216–1221, 2011
In vitro fermentation characteristics of diets with different forage/concentrate ratios: comparison of rumen and faecal inocula
Authors: Zicarelli Fabio , Calabrò Serena , Cutrignelli Monica I , Infascelli Federico , Tudisco Raffaella , Bovera Fulvia , Piccolo Vincenzo
Published: February 2011

BACKGROUND: The aim of this trial was to evaluate the replacement of rumen fluid with faeces as inoculum in studying the in vitro fermentation characteristics of diets for ruminants using the in vitro gas production technique. Six iso‐protein diets with different forage/concentrate ratios were incubated with rumen fluid (RI) or faeces (FI) collected from sheep.

RESULTS: Most of the fermentation parameters were influenced by diet and inoculum (P < 0.01). With both inocula, organic matter degradability (dOM), cumulative gas production (OMCV) and maximum fermentation rate (Rmax) increased as the amount of concentrate in the diet increased. Rmax was lower with FI vs RI (P < 0.01); dOM was higher with FI vs RI and the diet × inoculum interaction was significant. As expected, with both inocula, Rmax increased as the neutral detergent fibre content of the diet decreased. Significant correlations were obtained using both inocula between OMCV/dOM and gas/volatile fatty acid (VFA), while the correlation VFA/dOM was significant only with FI. The microbial biomass yield calculated by stoichiometric analysis for all diets was higher with FI vs RI. With FI the organic matter used for microbial growth showed an overall decreasing trend as the amount of concentrate in the diet increased.

CONCLUSION: The results indicate that both faeces and rumen fluid from sheep have the potential to be used as inoculum for the in vitro gas production technique. Copyright © 2011 Society of Chemical Industry
When to start an aromatase inhibitor: Now or later?
Authors: Doughty Julie C.
Published: February 2011

Among women who have undergone surgery for breast cancer, the risk of recurrence, especially distant metastases, peaks 1–2 years postsurgery. Recent clinical trial evidence suggests that initial adjuvant therapy with an aromatase inhibitor (AI) can reduce this early risk of recurrence. According to the recently updated St Gallen consensus statement, initial AI therapy is the preferred strategy for adjuvant endocrine therapy in postmenopausal women with hormone receptor‐positive breast cancer. J. Surg. Oncol. 2011;103:730–738. © 2011 Wiley‐Liss, Inc.
Impact of intratumoral thymidylate synthase expression on prognosis after surgical resection for ampullary carcinoma
Authors: Kato Yasushi , Murakami Yoshiaki , Uemura Kenichiro , Sudo Takeshi , Hashimoto Yasushi , Hiyama Eiso , Sueda Taijiro
Published: February 2011

Background and Objectives

This study evaluated possible prognostic value of expression level of intratumoral thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), and orotate phosphoribosyltransferase (OPRT) in patients with resected ampullary carcinoma.

Methods

Immunohistochemical staining evaluated intratumoral TS, DPD, and OPRT expression in 52 surgical specimens of patients with ampullary carcinoma. Relationships between clinicopathological factors including intratumoral TS, DPD, or OPRT expressions and survival was evaluated by univariate and multivariate analysis.

Results

High intratumoral DPD, OPRT, and TS expressions were found in 19 (37%), 30 (58%), and 23 (44%) of cases, respectively. Patients with high TS expression had more advanced‐stage disease than those with low TS expression. Univariate analysis revealed that gender, perineural invasion, lymph node status, UICC pT factor, UICC stage, OPRT expression, and TS expression correlated significantly (P < 0.05) with disease‐specific survival. Only perineural invasion (P = 0.043) and TS expression (P = 0.019) were independent prognostic factors of disease‐specific survival by multivariate survival analysis. Five‐year disease‐specific survival rates of patients with high and low intratumoral TS expression were 47% and 91%, respectively.

Conclusions

Intratumoral TS expression level may be a potent predictor of prognosis after surgical resection for ampullary carcinoma. J. Surg. Oncol. 2011;103:663–668. © 2011 Wiley‐Liss, Inc.
TNM stage and grade in predicting the prognosis of operated, non‐functioning neuroendocrine carcinoma of the pancreas—a single‐institution experience
Authors: Sellner Franz , Thalhammer Sabine , Stättner Stefan , Karner Josef , Klimpfinger Martin
Published: February 2011

Objective

To evaluate the prognostic significance of TNM and grading categories in curatively resected non‐functioning neuroendocrine pancreatic carcinoma (nfnepC).

Method

Eighteen nfnepC were retrospectively analyzed for differences in survival.

Results

(1) There was a correlation between pT (P = 0.026), respectively pM categories (P = 0.016) and survival. (2) G categories and length of survival were closely correlated (P = 0.0036). (3) Disease stages I–IV had a significant effect on survival (P = 0.051). (4) The WHO classification in well and poorly differentiated carcinomas proved to be the most conclusive predictive factor (P = 0.0009). (5) Subgroups with significantly different prognoses determined by histological grade were present within disease stage II.

Conclusions

The retrospective analysis showed a good correlation between survival and pT, pM, tumor stage, G categories, and WHO classification in well and poorly differentiated carcinomas. Including histological differentiation in the staging system or carrying it out separately in well and poorly differentiated carcinomas, could enhance the predictive potential of TNM‐based disease stages. J. Surg. Oncol. 2011;104:17–21. © 2011 Wiley‐Liss, Inc.
Prospective comparison of peritumoral and subareolar injection of blue dye alone, for identification of sentinel lymph nodes in patients with early stage breast cancer
Authors: Kaklamanos Ioannis G. , Birbas Konstantinos , Syrigos Konstantinos , Bonatsos Vasilios G. , Bonatsos Gerasimos
Published: February 2011

Background and Objectives

Various techniques are used for the identification of the sentinel node (SLN). We prospectively compare the efficacy of SLN biopsy and the number of SLNs identified, by injecting methylene blue (MB) alone in the subareolar area (SA) or peritumorally (PT) in patients with early stage breast cancer

Methods

Patients were randomized in two groups (SA or PT injection). A linear regression model was used to estimate the effect of various parameters on the identification rate and on the number of SLNs retrieved.

Results

At least one SLN was identified in 61 of 66 (92.4%) procedures in the SA group and in 57 of 60 (95%) procedures in the PT group (P = 0.55). The mean number of SLNs removed with the SA injection method was 1.64 ± 0.6 nodes compared with 2.23 ± 0.7 nodes identified with the PT injection (range: 1–4, P < 0.001). The injection site was the only factor affecting the number of SLNs retrieved.

Conclusion

The use of MB alone is an efficient method for identification of the SLN. The PT injection route yields a higher number of SLNs than the SA route, comparable with the number of SLNs retrieved, when combined tracing agents and multiple injection sites are used. J. Surg. Oncol. 2011;104:37–40. © 2011 Wiley‐Liss, Inc.
Ionic liquid/ionic liquid dispersive liquid–liquid microextraction
Authors: Zhao Ru‐Song , Wang Xia , Li Fu‐Wei , Wang Shan‐Shan , Zhang Li‐Li , Cheng Chuan‐Ge
Published: February 2011

In this article, a novel and simple microextraction method, termed ionic liquid/ionic liquid dispersive liquid–liquid microextraction (IL/IL‐DLLME), has been designed and developed for the rapid enrichment and analysis of environmental pollutants. Instead of using hazardous organic solvents, two kinds of ILs, hydrophobic IL and hydrophilic IL, were used as extraction solvent and disperser solvent in IL/IL‐DLLME step, respectively. Permethrin and biphenthrin, two of the often‐used pyrethroid pesticides, were used as model compounds. Factors that may affect the enrichment efficiencies were investigated and optimized in detail. Under optimum conditions, permethrin and biphenthrin exhibited a wide linear relationship over the range 1–100 μg/L. For permethrin and biphenthrin, the precisions were 4.65–7.78%, and limits of detection were found to be 0.28 and 0.83 μg/L, respectively. Satisfactory results were achieved when the present method was applied to analyze the target compounds in real‐world water samples with spiked recoveries over the range 84.1–113.5%. All these facts indicated that IL/IL‐DLLME is a simple and rapid alternative for the enrichment and analysis of environmental pollutants and will have a wide application perspective in the future.
Direct injection analysis of fatty and resin acids in papermaking process waters by HPLC/MS
Authors: Valto Piia , Knuutinen Juha , Alén Raimo
Published: February 2011

A novel HPLC‐atmospheric pressure chemical ionization/MS (HPLC‐APCI/MS) method was developed for the rapid analysis of selected fatty and resin acids typically present in papermaking process waters. A mixture of palmitic, stearic, oleic, linolenic, and dehydroabietic acids was separated by a commercial HPLC column (a modified stationary C18 phase) using gradient elution with methanol/0.15% formic acid (pH 2.5) as a mobile phase. The internal standard (myristic acid) method was used to calculate the correlation coefficients and in the quantitation of the results. In the thorough quality parameters measurement, a mixture of these model acids in aqueous media as well as in six different paper machine process waters was quantitatively determined. The measured quality parameters, such as selectivity, linearity, precision, and accuracy, clearly indicated that, compared with traditional gas chromatographic techniques, the simple method developed provided a faster chromatographic analysis with almost real‐time monitoring of these acids.
Enhancing self‐report assessment of PTSD: Development of an item bank
Authors: Del Vecchio Nicole , Elwy A. Rani , Smith Eric , Bottonari Kathryn A. , Eisen Susan V.
Published: February 2011

The authors report results of work to enhance self‐report posttraumatic stress disorder (PTSD) assessment by developing an item bank for use in a computer‐adapted test. Computer‐adapted tests have great potential to decrease the burden of PTSD assessment and outcomes monitoring. The authors conducted a systematic literature review of PTSD instruments, created a database of items, performed qualitative review and readability analysis, and conducted cognitive interviews with veterans diagnosed with PTSD. The systematic review yielded 480 studies in which 41 PTSD instruments comprising 993 items met inclusion criteria. The final PTSD item bank includes 104 items representing each of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM‐IV; American Psychiatric Association [APA], 1994), PTSD symptom clusters (reexperiencing, avoidance, and hyperarousal), and 3 additional subdomains (depersonalization, guilt, and sexual problems) that expanded the assessment item pool.
ADAPTING TO CLIMATE CHANGE BY IMPROVING WATER PRODUCTIVITY OF SOILS IN DRY AREAS
Authors: Qadir M. , Noble A. D. , Chartres C.
Published: February 2011

Considering extreme events of climate change and declining availability of appropriate quality water and/or highly productive soil resources for agriculture in dryland regions, the need to produce more food, forage and fibre will necessitate the effective utilization of marginal‐quality water and soil resources. Recent research and practices have demonstrated that effective utilization of these natural resources in dry areas can improve agricultural productivity per unit area and per unit water applied. This paper focuses on the following three case studies as examples: (1) low productivity soils affected by high levels of magnesium in soil solution and on the cation exchange complex; (2) degraded sandy soils under rainfed conditions characterized by low water‐holding capacity, organic matter and clay content and (3) abandoned irrigated soils with elevated levels of salts inhibiting growth of income generating crops. The results of these studies demonstrate that application of calcium‐supplying phosphogypsum to high‐magnesium soils, addition of clays to light textured degraded soils and phytoremediation of abandoned salt‐affected soils significantly improved productivity of these soils. Furthermore, under most circumstances, these interventions were economically viable, revealing that the efficient use of marginal‐quality water and soil resources has the potential to improve livelihoods amid growing populations in dry areas while reversing the natural resource degradation trend. However, considerably more investment and policy‐level interventions are needed to tackle soil degradation/remediation issues across both irrigated and dryland agricultural environments if the major challenge of producing enough food, forage and fibre is to be met. Copyright © 2011 John Wiley & Sons, Ltd.
Integrated land degradation monitoring and assessment: Horizontal knowledge management at the national and international levels
Authors: Chasek P. , Essahli W. , Akhtar‐Schuster M. , Stringer L. C. , Thomas R.
Published: February 2011

The need for improved horizontal knowledge management at the national and international levels is essential for monitoring and assessment of land degradation and desertification. At the national level, governments utilise scientific, socio‐economic and technical data and information for strategic planning, priority setting and national environment and development planning. However, challenges including the lack of capacity and lack of collaboration and sharing of information across governments affect responses to and the effectiveness of monitoring and knowledge exchange, along with the ability to effectively implement treaties. At the international level, a number of Multilateral Environmental Agreements (MEAs) share cross‐sectoral themes related to research and monitoring, information exchange, technology transfer, capacity building and financial resources. The need for increased synergies stems from the similarities between the issues they address. Challenges for improving knowledge management at the international level include insufficient interaction between the scientific bodies of the various MEAs; duplication of reporting, monitoring and assessment efforts; limited knowledge management between the various assessments addressing ecosystems and biological diversity during the past decade; and insufficient collaboration between the United Nations Convention to Combat Desertification (UNCCD), the UN system and the international non‐governmental organisation (NGO) community. This paper examines these challenges and offers recommendations on how monitoring and assessment knowledge can be better managed at the national and international levels. Copyright © 2011 John Wiley & Sons, Ltd.