bluuebunny/crossref_metadata_2025 huggingface dataset:
Sex‐specific familial risks of urinary bladder cancer and associated neoplasms in Sweden
Authors: Bermejo Justo Lorenzo , Sundquist Jan , Hemminki Kari
Published: November 2008

Male gender and a family history of cancer are established risk factors for urinary bladder neoplasms. This study used the latest update of the Swedish Family‐Cancer Database, which includes 42,255 bladder cancer patients, to investigate the sex‐specific incidences and types of tumors in relatives of bladder cancer patients. Men with parents or siblings affected by lung cancer did not show an increased risk of bladder neoplasms. Among women, the familial association was restricted to daughters of women with lung cancer. Brothers showed higher risks than the sons of bladder cancer patients. Men older than 54 years were at an increased risk of bladder cancer only if their fathers or siblings were diagnosed after age 65 years. The present data indicated a limited contribution of smoking to the familial clustering of bladder cancer with other neoplasms. The dependence of the relative risks on the type of familial relationship probably reflected a heterogeneous character of familial aggregation. Age‐specific results suggested differential risk factors for tumors diagnosed before 50 years of age versus neoplasms detected later in life. The present data may guide the design of forthcoming gene identification studies and the interpretation of the genome‐wide association studies that are about to be published. © 2008 Wiley‐Liss, Inc.
Three genetic developmental stages of papillary renal cell tumors: Duplication of chromosome 1q marks fatal progression
Authors: Szponar Adrianna , Zubakov Dmitry , Pawlak Justyna , Jauch Anna , Kovacs Gyula
Published: November 2008

Papillary renal cell tumors (RCT) make up a cytomorphologically and biologically heterogeneous group of kidney cancers including renal cell adenomas (RCA) and renal cell carcinomas (RCC). To find genetic markers landmarking the tumor progression, we have evaluated the genetic alterations obtained by karyotyping, chromosomal and array‐CGH and compared with the cytological characteristics and biological behavior of 60 papillary RCTs. Based on the genetic and clinical data, we have separated 3 groups of tumors and proposed 3 genetically defined developmental stages of papillary RCTs. Papillary RCAs are characterized by combined trisomy of chromosomes 7 and 17, whereas papillary RCCs displayed additional trisomies of 3q, 8q, 12q, 16q and 20q. In addition to the genetic changes occurring in the second group, the third group of tumors was characterized by 1q gain and 6q, 8p, 9p and 14q losses. Kaplan‐Meier analysis revealed a significant association between chromosome 1q gain and deadly outcome of the disease. The cytomorphological variation and size of tumors in the second and third groups did not correlate with the clinical outcome. Therefore, we suggest that our genetic classification system landmarking papillary RCA, papillary RCC without and with progression offer a better system to characterize the tumor biology of clinical significance than a cellular/morphological classification. © 2008 Wiley‐Liss, Inc.
Genipin enhances the mechanical properties of tissue‐engineered cartilage and protects against inflammatory degradation when used as a medium supplement
Authors: Lima Eric G. , Tan Andrea R. , Tai Timon , Marra Kacey G. , DeFail Alicia , Ateshian Gerard A. , Hung Clark T.
Published: November 2008

Genipin is a naturally‐derived biocompatible cross‐linking agent commonly used to generate three dimensional tissue‐engineered scaffolds or to fix biologically derived scaffolds prior to implantation. Here we propose a novel use for genipin as a long‐term culture medium supplement to promote cross‐linking of de novo cell products that are produced in engineered cartilage. We hypothesize that the application of genipin will stabilize the extracellular matrix components and increase the mechanical properties of developing engineered cartilage. Chondrocytes encapsulated in agarose hydrogel (a neutrally charged polysaccharide scaffold that is unaffected by genipin cross‐linking) were cultured in a chemically‐defined growth medium that was supplemented with varying concentrations of genipin (22 μM, 220 μM, 2200 μM) for various durations (continuous or intermittent). Tissues developed significantly higher mechanical properties (+28% dynamic modulus and +20% Young's modulus) by day 42 with genipin treatment compared to untreated controls. These increases were not immediate, but presented over culture time after genipin treatment. The genipin treated groups were also more resistant to cytokine‐induced degradation with interleukin‐1α; maintaining an EY (+218%), G• (+390%) and glycosaminoglycan (GAG) content (+477%) over genipin‐untreated constructs subjected to interleukin. We hypothesize two mechanisms through which the physical enhancement of tissue properties may be fostered: (1) by cross‐link mediated reorganization and enhanced retention of cell‐elaborated extracellular matrix components, and (2) through reduction of the loss of extracellular matrix components by increasing their resilience to catabolic degradation. These studies demonstrate a potential use of genipin as a medium supplement to develop enhanced engineered cartilage. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Calcium sulfate: Properties and clinical applications
Authors: Thomas Mark V. , Puleo David A.
Published: November 2008

Calcium sulfate (CS) has enjoyed a longer history of clinical use than most currently available biomaterials. It is well‐tolerated when used to fill bone defects and undergoes rapid and complete resorption without eliciting a significant inflammatory response. The raw material from which it is made is relatively inexpensive and abundant. In addition, CS can be used as a vehicle to deliver antibiotics, pharmacologic agents, and growth factors. It has found wide use in orthopedics and dentistry, and has been used in a variety of clinical applications, including the periodontal defect repair, the treatment of osteomyelitis, sinus augmentation, and as an adjunct to dental implant placement. Despite these advantages, the material has not enjoyed the popularity of many other regenerative materials, although there has been a recent resurgence of interest in the material. This review examines the properties and clinical applications of CS, with an emphasis on dental applications of the material. Limitations of the material are discussed as well as suggestions for future research. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Profilin‐1 overexpression upregulates PTEN and suppresses AKT activation in breast cancer cells
Authors: Das Tuhin , Bae Yong Ho , Wells Alan , Roy Partha
Published: November 2008

Profilin‐1 (Pfn1), a ubiquitously expressed actin‐binding protein, has been regarded as a tumor‐suppressor molecule for breast cancer. Since AKT signaling impacts cell survival and proliferation, in this study we investigated whether AKT activation in breast cancer cells is sensitive to perturbation of Pfn1 expression. We found that even a moderate overexpression of Pfn1 leads to a significant reduction in phosphorylation of AKT in MDA‐MB‐231 breast cancer cells. We further demonstrated that Pfn1 overexpression in MDA‐MB‐231 cells is associated with a significant reduction in the level of the phosphoinositide regulator of AKT, PIP3, and impaired membrane translocation of AKT that is required for AKT activation, in response to EGF stimulation. Interestingly, Pfn1‐overexpressing cells showed post‐transcriptional upregulation of PTEN. Furthermore, when PTEN expression was silenced, AKT phosphorylation was rescued, suggesting PTEN upregulation is responsible for Pfn1‐dependent attenuation of AKT activation in MDA‐MB‐231 cells. Pfn1 overexpression induced PTEN upregulation and reduced AKT activation were also reproducible features of BT474 breast cancer cells. These findings may provide mechanistic insights underlying at least some of the tumor‐suppressive properties of Pfn1. J. Cell. Physiol. 218: 436–443, 2009. © 2008 Wiley‐Liss, Inc.
Distinct expression of muscle‐specific MicroRNAs (myomirs) in brown adipocytes
Authors: Walden Tomas B. , Timmons James A. , Keller Pernille , Nedergaard Jan , Cannon Barbara
Published: November 2008

MicroRNAs, a novel class of post‐transcriptional gene regulators, have been demonstrated to be involved in several cellular processes regulating the expression of protein‐coding genes. Here we examine murine white and brown primary cell cultures for differential expression of miRNAs. The adipogenesis‐related miRNA miR‐143 was highly expressed in mature white adipocytes but was low in mature brown adipocytes. Three classical “myogenic” miRNAs miR‐1, miR‐133a and miR‐206 were absent from white adipocytes but were specifically expressed both in brown pre‐ and mature adipocytes, reinforcing the concept that brown adipocytes and myocytes derive from a common cell lineage that specifies energy‐dissipating cells. Augmentation of adipocyte differentiation status with norepinephrine or rosiglitazone did not affect the expression of the above miRNAs, the expression levels of which were thus innately regulated. However, expression of the miRNA miR‐455 was enhanced during brown adipocyte differentiation, similarly to the expression pattern of the brown adipocyte differentiation marker UCP1. In conclusion, miRNAs are differentially expressed in white and brown adipocytes and may be important in defining the common precursor cell for myocytes and brown adipocytes and thus have distinct roles in energy‐storing versus energy‐dissipating cells. J. Cell. Physiol. 218: 444–449, 2009. © 2008 Wiley‐Liss, Inc.
Vertebral development of modern salamanders provides insights into a unique event of their evolutionary history
Authors: Boisvert Catherine Anne
Published: November 2008

The origin of salamanders and their interrelationships to the two other modern amphibian orders (frogs and caecilians) are problematic owing to an 80–100 million year gap in the fossil record between the Carboniferous to the Lower Jurassic. This is compounded by a scarcity of adult skeletal characters linking the early representatives of the modern orders to their stem‐group in the Paleozoic. The use of ontogenetic characters can be of great use in the resolution of these questions. Growth series of all ten modern salamander families (a 120 cleared and stained larvae) were examined for pattern and timing of vertebral elements chondrification and ossification. The primitive pattern is that of the neural arches developing before the centra, while the reverse represents the derived condition. Both the primitive and derived conditions are observed within the family Hynobiidae, whereas only the derived condition is observed in all other salamanders. This provides support to the claims that Hynobiidae is both the most basal of modern families and potentially polyphyletic (with Ranodon and Hybobius forming the most basal clade and Salamandrella being a part of the most derived clade). This provides insight into a unique event in salamander evolutionary history and suggests that the developmental pattern switch occurred between the Triassic and the mid‐Jurassic before the last major radiation. J. Exp. Zool. (Mol. Dev. Evol.) 312B:1–29, 2009. © 2008 Wiley‐Liss, Inc.
Accelerated bilateral dynamic contrast‐enhanced 3D spiral breast MRI using TSENSE
Authors: Han Misung , Daniel Bruce L. , Hargreaves Brian A.
Published: November 2008

Purpose

To assess the ability of adaptive sensitivity encoding incorporating temporal filtering (TSENSE) to accelerate bilateral dynamic contrast‐enhanced (DCE) 3D breast MRI.

Materials and Methods

Bilateral DCE breast magnetic resonance imaging (MRI) exams were performed using a dual‐band water‐only excitation and a “stack‐of‐spirals” imaging trajectory. TSENSE was applied in the slab direction with an acceleration factor of 2. Four different techniques for sensitivity map calculation were compared by analyzing resultant contrast uptake curves qualitatively and quantitatively for 10 patient datasets. In addition, image quality and temporal resolution were compared between unaccelerated and TSENSE images.

Results

TSENSE can increase temporal resolution by a factor of 2 in DCE imaging, providing better depiction of contrast uptake curves and good image quality. Of the different methods tested, calculation of static sensitivity maps by averaging late postcontrast frames yields the lowest aliasing artifact level based on ROI analysis.

Conclusion

TSENSE acceleration combined with 3D spiral imaging is very time‐efficient, providing 11‐second temporal resolution and 1.1 × 1.1 × 3 mm3 spatial resolution over a 20 × 20 × 10 cm3 field of view for each breast. J. Magn. Reson. Imaging 2008;28:1425–1434. © 2008 Wiley‐Liss, Inc.
Fibrocystic change of the breast presenting as a focal lesion mimicking breast cancer in MR imaging
Authors: Chen Jeon‐Hor , Nalcioglu Orhan , Su Min‐Ying
Published: November 2008

Focal fibrocystic change (FCC) of the breast is a rare form of FCC. Imaging presentations of focal FCC are not well known. This study aimed to analyze its MR imaging features. Eleven patients of pathology‐proven focal FCC were retrospectively studied. Of the 11 patients, seven were mass (≥5 mm), two showed multiple foci, and two were focus (<5 mm). The lesion size ranged from 4–12 mm (mean 6.7 mm). Morphologically, three patients were suspected as malignancy. Using kinetic enhancement curve, 8 of 13 lesions were suspected to be malignant. Overall, nine patients (82%) were suspected for malignancy using either criterion. Using mammography, 6 of the 11 patients (55%) were diagnosed as malignancy. Breast sonography suspected malignancy in seven patients (7/10, 70%). No statistically significant difference was found in the three diagnostic methods. In pathology, all 11 patients showed the typical pathological features of fibrocystic change, with mixed components of stromal fibrosis, cyst formation, apocrine metaplasia, adenosis, and/or focal sclerosing adenosis. In conclusion, MR imaging features of focal FCC usually present as a mass or focus lesion with rapid enhancement and washout kinetics that mimic a malignant breast lesion and lead to unnecessary operation, especially in patients with contralateral malignant breast cancer. J. Magn. Reson. Imaging 2008;28:1499–1505. © 2008 Wiley‐Liss, Inc.
Safety of gadoversetamide in patients with acute and chronic myocardial infarction
Authors: Huber S. , Muthupillai R. , Cheong B. , Wible J.H. , Shah D. , Woodard P. , Grothues F. , Mahrholdt H. , Rochitte C.E. , Masoli O. , Kim R.J. , Schwaiger C.M. , Fuisz A. , Kramer C. , van Rossum A.C. , Biederman R. , Lombardi M. , Martin E. , Kevorkian R. , Flamm S.D.
Published: November 2008

Purpose

To assess the safety data from two large, multicenter, phase 2 trials on the use of gadoversetamide (OptiMARK, Tyco Healthcare/Mallinckrodt, St. Louis, MO) as a contrast agent in delayed hyperenhancement magnetic resonance imaging (DE‐MRI) in patients with acute and chronic myocardial infarction (MI).

Materials and Methods

The study population from both trials comprised 577 patients who were randomly assigned to one of four dose groups (0.05, 0.1, 0.2, or 0.3 mmol/kg) before undergoing DE‐MRI. Safety evaluations included physical and electrocardiographic (ECG) examinations. Vital signs, laboratory values, adverse events (AE), and serious adverse events (SAE) were monitored before and after contrast administration.

Results

Of the 577 patients who received gadoversetamide, 124 (21.5%) reported a total of 164 AEs; most were mild (139 AEs; 84.8%) or moderate (25 AEs; 15.2%). ECG‐related changes were the most frequent AE. Site investigators judged only eight AEs as likely related to gadoversetamide and only two of the eight as clinically relevant. Further evaluation suggested neither AE was related to gadoversetamide. Two SAEs were reported, but none was judged related to gadoversetamide by the site investigators.

Conclusion

Gadoversetamide is safe for use in patients with acute or chronic MI up to a dose of 0.3 mmol/kg. J. Magn. Reson. Imaging 2008;28:1368–1378. © 2008 Wiley‐Liss, Inc.
Regional right ventricular function and timing of contraction in healthy volunteers evaluated by strain‐encoded MRI
Authors: Hamdan Ashraf , Thouet Thomas , Sebastian Kelle , Paetsch Ingo , Gebker Rolf , Wellnhofer Ernst , Schnackenburg Bernhard , Fahmy Ahmed S. , Osman Nael F. , Fleck Eckart
Published: November 2008

Purpose

To prospectively determine the feasibility and accuracy of strain‐encoded (SENC) magnetic resonance imaging (MRI) for the characterization of the right ventricular free wall (RVFW) strain and timing of contraction at 3.0 Tesla (3T) MRI.

Materials and Methods

In 12 healthy volunteers the RVFW was divided into three segments (anterior, lateral, and inferior) in each of three short‐axis (SA) slices (apical, mid, and basal) and into three segments (apical, mid, and basal) in a four‐chamber view. The study was repeated on a different day and interobserver and interstudy agreements were evaluated.

Results

Maximal systolic longitudinal strain values were highest at the apex and base, with a pronounced decrease in the medial segments (apex: –19.1% ± 1.4; mid: –17.4% ± 2; base: –19.4% ± 2.4, P < 0.001), and maximal systolic circumferential strain showed the highest values at the apex (apex: –18.1% ± 1.7; mid: –17.6% ± 1.2; base: –16.6% ± 0.9, P < 0.001). Peak systolic longitudinal and circumferential shortening occurred earliest at the apex compared to the mid‐ventricle and base. Excellent interobserver and interstudy correlation and agreement were observed.

Conclusion

The use of SENC MRI for the assessment of normal RV contraction pattern is feasible and accurate in 3T MRI. J. Magn. Reson. Imaging 2008;28:1379–1385. © 2008 Wiley‐Liss, Inc.
Measurement of common carotid artery lumen dynamics during the cardiac cycle using magnetic resonance TrueFISP cine imaging
Authors: Chow Tracy Y. , Cheung Jerry S. , Wu Yin , Guo Hua , Chan Kevin C. , Hui Edward S. , Wu Ed X.
Published: November 2008

Purpose

To demonstrate magnetic resonance (MR) measurements of vascular lumen dynamics in common carotid arteries by using true fast imaging with steady‐state precession (TrueFISP) cine imaging with an aim to provide additional physiologic information on the vessels.

Materials and Methods

The left and right common carotid arteries were studied in normal young men (N = 6; age = 21–24 years; body weight = 130–175 lbs) using electrocardiogram (ECG)‐triggered TrueFISP cine imaging at 20 frames per cardiac cycle. Lumen area waveforms were characterized with specific time and amplitude ratios. Distension values were quantified.

Results

Distension values were measured at 25.92 ± 2.58% and 27.58 ± 4.44% for the left and right common carotid arteries, respectively. These findings are consistent with those previously documented using ultrasound imaging in a similar age group. Consistent lumen area waveform characteristics were found among the subjects studied.

Conclusion

These findings demonstrate for the first time that the use of TrueFISP cine imaging is a robust, rapid technique for quantifying carotid lumen area dynamics and distension, which may be valuable in characterizing and diagnosing cardiovascular diseases. J. Magn. Reson. Imaging 2008;28:1527–1532. © 2008 Wiley‐Liss, Inc.
Vertebral blood perfusion reduction associated with vertebral bone mineral density reduction: A dynamic contrast‐enhanced MRI study in a rat orchiectomy model
Authors: Wang Yi‐Xiang J. , Zhang Ya‐Feng , Griffith James F. , Zhou Hua , Yeung David K.W. , Kwok Timothy C. , Qin Ling , Ahuja Anil T.
Published: November 2008

Purpose

To investigate the relationship between vertebral blood perfusion and vertebral bone mineral density (BMD) in a rat orchiectomy (ORX) model.

Materials and Methods

Nine 6‐month‐old male Wistar‐Kyoto rats were used. Computed tomography (CT) bone densitometry and dynamic MRI were performed at baseline and four weeks post‐ORX. MRI was performed on a 1.5T clinical MR scanner with a small surface coil placed under the rat lumbar spine region. A sagittal midsection of the lumbar spine was prescribed. Dynamic MRI was performed after a bolus injection of gadolinium‐tetraazacyclododecane tetraacetic acid (Gd‐DOTA) (0.3 mmol/kg) administered through a tail vein cannula. At a temporal resolution of 0.6 seconds, 800 images were acquired. Regions‐of‐interest were drawn comprising the medullary component of lumbar vertebrae L3–L6. Maximum enhancement was analyzed.

Results

Satisfactory CT and MRI data for analysis was obtained in all animals. Vertebral BMD decreased by 16.6% at four weeks post‐ORX (1.134 ± 0.035 vs. 0.946 ± 0.027 g/cm3, P = 0.008). MRI maximum enhancement decreased by 17% at four weeks post‐ORX (151.5 ± 12.0% vs. 125.8 ± 9.9%, P = 0.015).

Conclusion

Vertebral blood perfusion reduction is associated with vertebral BMD reduction in a male rat osteoporosis model. Perfusion MRI provides a new investigative technique for osteoporosis experimental research. J. Magn. Reson. Imaging 2008;28:1515–1518. © 2008 Wiley‐Liss, Inc.
Venous congestion associated with developmental venous anomaly: Findings on susceptibility weighted imaging
Authors: Amemiya Shiori , Aoki Shigeki , Takao Hidemasa
Published: November 2008

A case of venous congestion associated with developmental venous anomaly (DVA) in a 5‐year‐old girl who presented with acute deterioration of consciousness is reported. Susceptibility‐weighted imaging revealed abnormal structures connected to the central collector of a DVA, which were not shown on other sequences. These structures were considered to be presumably thrombosed medullary veins. J. Magn. Reson. Imaging 2008;28:1506–1509. © 2008 Wiley‐Liss, Inc.
MR angiography of the cerebral perforating arteries with magnetization prepared anatomical reference at 7T: Comparison with time‐of‐flight
Authors: Zwanenburg Jaco J.M. , Hendrikse Jeroen , Takahara Taro , Visser Fredy , Luijten Peter R.
Published: November 2008

Purpose

To develop a magnetic resonance imaging (MRI) protocol that visualizes both the perforating arteries and the related anatomy in a single acquisition at 7T.

Material and Methods

T1‐weighted magnetization prepared imaging (MPRAGE) was empirically modified for use as angiography method at 7T. The resulting sequence depicts the vasculature simultaneously with the surrounding anatomical structures, and is referred to as “magnetization prepared anatomical reference MRA” (MPARE‐MRA). The method was compared to time‐of‐flight (TOF) MRA in seven healthy subjects. The conspicuity of the perforating arteries and the contrast between gray and white matter were evaluated both quantitatively by contrast‐to‐noise (CNR) measurements, and qualitatively by two radiologists who scored the images.

Results

The contrast‐to‐noise ratio (CNR) between blood and background was 28 ± 9 for MPARE‐MRA and 35 ± 16 for TOF‐MRA, indicating good conspicuity of the vessels. CNR values were: internal capsule (IC) vs. caudate head (CH): 4.2 ± 0.7; IC vs. putamen: 3.5 ± 0.6; white matter vs. gray matter: 9.7 ± 2.5.

Conclusion

The benefits of ultra‐high‐field MRI can transform MPRAGE into a new angiography method to image small vessels and associated parenchyma at the same time. This technique can be used to study the correlation between tissue damage and vascular pathology. J. Magn. Reson. Imaging 2008;28:1519–1526. © 2008 Wiley‐Liss, Inc.
1H HR‐MAS spectroscopy for quantitative measurement of choline concentration in amniotic fluid as a marker of fetal lung maturity: Inter‐ and intraobserver reproducibility study
Authors: Joe Bonnie N. , Vahidi Kiarash , Zektzer Andrew , Chen Mei‐Hsiu , Clifton Matthew S. , Butler Thomas , Keshari Kayvan , Kurhanewicz John , Coakley Fergus , Swanson Mark G.
Published: November 2008

Purpose

To determine the intra‐ and interobserver reproducibility of human amniotic fluid metabolite concentration measurements (including potential markers of fetal lung maturity) detectable by MR spectroscopy.

Materials and Methods

1H high‐resolution magic angle spinning (HR‐MAS) spectroscopy was performed at 11.7T on 23 third‐trimester amniotic fluid samples. Samples were analyzed quantitatively using 3‐(trimethylsilyl)propionic‐2,2,3,3‐d4 acid (TSP) as a reference. Four observers independently quantified eight metabolite regions (TSP, lactate doublet and quartet, alanine, citrate, creatinine, choline, and glucose) twice from anonymized, randomized spectra using a semiautomated software program.

Results

Excellent inter‐ and intraobserver reproducibility was found for all metabolites. Intraclass correlation as a measure of interobserver agreement for the four readers ranged from 0.654 to 0.995. A high correlation of 0.973 was seen for choline in particular, a major component of surfactant. Pearson correlation as a measure of intraobserver reproducibility ranged from 0.478 to 0.999.

Conclusion

Quantification of choline and other metabolite concentrations in amniotic fluid by high‐resolution MR spectroscopy can be performed with high inter‐ and intraobserver reproducibility. Demonstration of reproducible metabolite concentration measurements is a critical first step in the search for biomarkers of fetal lung maturity. J. Magn. Reson. Imaging 2008;28:1540–1545. © 2008 Wiley‐Liss, Inc.
Evaluating the severity of nonalcoholic steatohepatitis with superparamagnetic iron oxide‐enhanced magnetic resonance imaging
Authors: Tomita Kengo , Tanimoto Akihiro , Irie Rie , Kikuchi Masahiro , Yokoyama Hirokazu , Teratani Toshiaki , Suzuki Takahiro , Taguchi Takashi , Noguchi Masaaki , Ohkura Tamiko , Hibi Toshifumi
Published: November 2008

Purpose

To evaluate the utility of noninvasive assessment of human nonalcoholic fatty liver disease (NAFLD) patients using superparamagnetic iron oxide (SPIO)‐enhanced MRI.

Materials and Methods

Nineteen NAFLD patients underwent SPIO‐enhanced MRI. The values of τ, a time constant for an exponential approximation, were calculated using gradient‐echo echo‐planar imaging, and the values of %T2, a marker of the T2 relaxation effect of SPIO, were calculated using T2‐weighted fast spin‐echo images. Correlations between these values and the histological NAFLD activity scores were evaluated. The study protocol was approved by our Institutional Review Board and all patients gave informed consent.

Results

There was a statistically significant relationship between the NAFLD activity scores and the τ values (r = 0.66, P = 0.002). The %T2 values were also significantly correlated with the NAFLD activity score (r = −0.58, P = 0.009). A cutoff τ value of 42.8 predicted “definitive NASH” (NAFLD activity score ≥5) with a specificity of 66.7% and a sensitivity of 99.9%, whereas a cutoff %T2 value of 32.5 predicted “definitive NASH” with a specificity of 72.7% and a sensitivity of 87.5%.

Conclusion

Noninvasive SPIO‐enhanced MRI may be helpful for identifying NASH patients among patients suspected of having NAFLD. J. Magn. Reson. Imaging 2008;28:1444–1450. © 2008 Wiley‐Liss, Inc.
MR imaging findings of early bile duct cancer
Authors: Lee Dong Ho , Lee Jeong Min , Kim Kyung Won , Park Hee Sun , Kim Se Hyung , Lee Jae Young , Han Joon Koo , Choi Byung Ihn
Published: November 2008

Purpose

To retrospectively evaluate the MR imaging features of early bile duct cancer and to correlate them with the clinicopathologic findings.

Materials and Methods

This retrospective study was approved by our institutional review board, and informed consent was waived. Seventeen patients with surgically proven early bile duct cancer who had undergone preoperative MR cholangiopancreatography with gadolinium‐enhanced MR imaging, were included in this study. Two, experienced radiologists evaluated the MR images in consensus regarding the following findings: tumor number and morphology; signal intensity of the tumor; sharpness of the outer border of the bile duct wall; enhancement pattern of the tumor; and the presence of enlarged peribiliary lymph nodes. Another radiologist measured the SNR of the tumor and bile duct wall on gadolinium‐enhanced MRI during the dynamic phases to evaluate the tumor enhancement degree.

Results

In all patients, MR imaging demonstrated single or multiple intraluminal bile duct masses showing a sharply defined outer margin. The most common enhancement pattern of the biliary lesions showed heterogeneous amorphous enhancement or heterogeneous enhancement with central, dot‐like structures or vascular structures (76.5%, 13/17 patients). The difference of SNR between bile duct and tumor was greatest in the equilibrium phase (P < 0.05).

Conclusion

MRCP combined with dynamic contrast‐enhanced MRI can be useful for detecting early bile duct cancers. Common MR findings of early bile duct cancer include one or more inhomogeneously enhancing intraductal masses with clear outer margins and preservation of the bile duct wall. J. Magn. Reson. Imaging 2008;28:1466–1475. © 2008 Wiley‐Liss, Inc.
Measurement of T1, T2, and magnetization transfer properties during embryonic development at 7 Tesla using the chicken model
Authors: Boss Andreas , Oppitz Matthias , Wehrl Hans F. , Rossi Cristina , Feuerstein Markus , Claussen Claus D. , Drews Ulrich , Pichler Bernd J. , Schick Fritz
Published: November 2008

Purpose

To evaluate whether techniques of high field magnetic resonance imaging may be used to characterize embryonic tissue during proliferation and differentiation.

Materials and Methods

Thirteen chicken embryos with incubation times between 5 days and 16 days have been measured in a small animal magnetic resonance imager (ClinScan, Bruker) at 7 Tesla using the built‐in resonator. T1, T2‐, and magnetization transfer imaging was performed using fast spin‐echo with inversion recovery, half acquisition single shot turbo spin‐echo, and spoiled gradient‐echo sequences with and without off‐resonance pulse, respectively. T1, T2, and magnetization transfer ratio (MTR) maps were calculated on a pixel‐by‐pixel basis.

Results

T1‐, T2‐, and MTR maps showed good image quality allowing for delineation of embryonic organs. During embryonic development, a decrease of T1 and T2 relaxation times was found, whereas, embryonic tissue typically showed an increase of magnetization transfer, for example, liver properties at day 5: T1 = 2431 ± 163 ms, T2 = 122 ± 12 ms, MTR = 9.2 ± 4.2%; liver properties at day 16: T1 = 1763 ± 89 ms, T2 = 71 ± 4 ms, MTR = 16.9 ± 2.2%.

Conclusion

Embryonic tissues show changing relaxation and magnetization transfer properties during development, therefore, high field MRI seems suitable for characterization of tissue replacement derived from embryonic stem cells. J. Magn. Reson. Imaging 2008;28:1510–1514. © 2008 Wiley‐Liss, Inc.
Simulation study of susceptibility gradients leading to focal myocardial signal loss
Authors: Anderson Douglas J. , Dendy Jeffrey M. , Paschal Cynthia B.
Published: November 2008

Purpose

To assess the cause of a “bite”‐shaped signal void artifact often seen in 1.5 Tesla (T) and 3T gradient echo MR images in myocardium along the infero‐apical border of the heart, MRI simulation was used to conduct experiments impossible in reality. Two previous studies attempting to explain the origin of this artifact came to different conclusions. One suggested deoxygenated blood in the posterior vein of the left ventricle (PVLV) leads to a susceptibility gradient that causes the artifact. The other suggested the difference in susceptibility between lung tissue and myocardium was responsible. This study assessed the relative effect of each possible cause.

Materials and Methods

Anthropometric phantoms were developed for use with a previously reported MRI simulator. The images were simulated at 3T with gradient echo scans using TE = 4 ms, TR = 25 ms, and θ = 25°.

Results

The simulations indicate that both susceptibility differences can lead to signal losses in the area of the artifact with contributions from the PVLV being more localized while lung tissue effects are stronger but more spatially distributed.

Conclusion

The data support the conclusion that both differences together, rather than one or the other, are responsible for the artifact. J. Magn. Reson. Imaging 2008;28:1402–1408. © 2008 Wiley‐Liss, Inc.
Brainstem functional magnetic resonance imaging: Disentangling signal from physiological noise
Authors: Harvey Ann K. , Pattinson Kyle T.S. , Brooks Jonathan C.W. , Mayhew Stephen D. , Jenkinson Mark , Wise Richard G.
Published: November 2008

Purpose

To estimate the importance of respiratory and cardiac effects on signal variability found in functional magnetic resonance imaging data recorded from the brainstem.

Materials and Methods

A modified version of the retrospective image correction (RETROICOR) method (Glover et al, [2000] Magn Reson Med 44:162–167) was implemented on resting brainstem echo‐planar imaging (EPI) data in 12 subjects. Fourier series were fitted to image data based on cardiac and respiratory recordings (pulseoximetry and respiratory turbine), including multiplicative terms that accounted for interactions between cardiac and respiratory signals. F‐tests were performed on residuals produced by regression analysis. Additionally, we evaluated whether modified RETROICOR improved detection of brainstem activation (in 11 subjects) during a finger opposition task.

Results

The optimal model, containing three cardiac (C) and four respiratory (R) harmonics, and one multiplicative (X) term, “3C4R1X,” significantly reduced signal variability without overfitting to noise. The application of modified RETROICOR to activation data increased group Z‐statistics and reduced putative false‐positive activation.

Conclusion

In addition to cardiac and respiratory effects, their interaction was also a significant source of physiological noise. The modified RETROICOR model improved detection of brainstem activation and would be usefully applied to any study examining this brain region. J. Magn. Reson. Imaging 2008;28:1337–1344. © 2008 Wiley‐Liss, Inc.
Recognizing α‐, β‐ or γ‐substitution in pyridines by mass spectrometry
Authors: Corilo Yuri E. , Eberlin Marcos N.
Published: November 2008

A general mass spectrometric method able to recognize the site of substitution of monosubstituted pyridines is described. The method requires that the molecule under investigation forms, upon ionization and dissociation, the respective α‐, β‐ or γ‐ pyridinium ion of m/z 78. Pyridinium ions are stable and common fragments of ionized and protonated pyridines and are found to function as appropriate structurally diagnostic fragment ions. They can be identified by their characteristic and nearly identical collision‐induced dissociation behavior and distinguished by the combined use of two structurally diagnostic ion/molecule reactions with acetonitrile and 2‐methyl‐1,3‐dioxolane. α‐, β‐ or γ‐substitution in pyridines can, therefore, be securely recognized via an MS‐only method based on structurally diagnostic ions and by the inspection of a single molecule (no need for intracomparisons within the whole set of isomers). Copyright © 2008 John Wiley & Sons, Ltd.
Relationships among activities of extracellular enzyme production and virulence against Helicoverpa armigera in Beauveria bassiana
Authors: Kaur Gurvinder , Padmaja V.
Published: November 2008

Extracellular enzymes produced by Beauveria bassiana, are believed to play a key role in cuticle hydrolysis. Enzyme production and pathogenicity has been found to be positively correlated. Twenty‐eight isolates of B. bassiana, collected from different geographical regions and host ranges were characterized by in vitro extracellular enzyme production and SDS–PAGE techniques for discerning biochemical basis for virulence among the different isolates. In vitro analysis of extracellular enzymes like protease, amylase, caseinase, chitinase and lipase was undertaken in an attempt to understand their relevance to virulence of the isolates. The different isolates of B. bassiana were evaluated for virulence to the second instar larvae of Helicoverpa armigera in laboratory bioassays. SDS–PAGE of total intracellular soluble proteins was also studied in order to understand affinities among the different isolates of B. bassiana. The relationship between enzyme production and pathogenicity and vice versa was nearly 50%. There was a 50% relationship associated with original insect host, pathogenicity and enzyme production. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of polyvalent and safe Bacillus thuringiensis strains with potential use for biocontrol
Authors: Raddadi Noura , Belaouis Abir , Tamagnini Isabella , Hansen Bjarne Munk , Hendriksen Niels Bohse , Boudabous Abdellatif , Cherif Ameur , Daffonchio Daniele
Published: November 2008

Sixteen Bacillus thuringiensis (Bt) strains were screened for their anti‐insect, antibacterial and antifungal determinants by phenotypic tests and PCR targeting major insecticidal proteins and complements, chitinases, lactonases, β‐1,3‐glucanases and zwittermicinA. Six strains had genes of at least two major insecticidal toxins and of insecticidal complements. With regard to fungal biocontrol, all the strains inhibited Fusarium oxysporum and Aspergillus flavus growth and four strains had all or most of the antifungal determinants examined, with strain Bt HD932 showing the widest antifungal activity spectrum. Autolysins, bacteriocin and AHL‐lactonases were produced by all or most of the tested strains with different activity spectra including pathogens like Listeria monocytogenes. Safety evaluation was carried out via PCR by screening the B. cereus psychrotolerance‐related genes, toxin genes and the virulence pleiotropic regulator plcR. Diarrheal enterotoxins and other toxin genes were widespread among the collection with strains Bt HD9 and H45 lacking psychrotolerance‐related genes, while five strains were positive. Only three strains (BMG1.7, H172, H156) resulted positive with primer sets targeting partial or complete plcR gene. By Vero Cell Assays, Bt HD868 followed by Bt HD9 were shown to be the safest strains. These polyvalent and safe Bt strains could be very promising in field application. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Improvement ofYarrowia lipolyticalipase production by fed‐batch fermentation
Authors: Fickers Patrick , Destain Jacqueline , Thonart Philippe
Published: November 2008

Two different types of fed‐batch fermentation were investigated to improve production yields of the Lip2 extracellular lipase inY. lipolyticamutant‐strain LgX64.81 grown in a 20l bioreactor. Compare to batch cultures, culture feeding with the complete medium led to a 2‐fold increased lipase production (2016 ± 76 U ml–1) whereas addition of a combination of glucose and olive oil led to a 3‐fold increase. The high level of lipase production obtained on glucose media withY.lipolyticaLgX64.81 could be related to its phenotype i.e. a lower sensibility to glucose catabolite repression due to a modification in the level ofHXK1expression. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Appropriate probe search method to specify groups in higher taxonomic ranks
Authors: Nakano Masahiro , Fukuda Kazumasa , Taniguchi Hatsumi
Published: November 2008

A new method for procedures using a computer to find out useful candidates for probes discriminating a certain group in higher ranks of bacteria is presented. In order to make the search of the probes systematic, two indices are proposed, i.e., Coincidence Ratio Inside Group (CRIG) and Coincidence Number Outside Group (CNOG), which indicate the rate of matching of probes inside or outside group respectively. Using two indices, allowance grades indicating usefulness of arbitrary sequence as a probe are defined from 9 (5 in species) to 0. Its application to the 16S rRNA gene of 2206 bacterial species selected from the Ribosomal Database Project (RDP‐II) (J.R. Cole et al., Nucleic Acids Res. 31: 442–443, 2003) is shown. Small nucleotide sequences of the length L (L = 15, 19, 23) were searched from about 550 bases. As a result of computer calculations, appropriate probes are found in all taxonomic ranks, in addition, it is found that 95% of genera can be identified uniquely. The method is useful for DNA chips or targeted PCR which can select a desirable bacteria set in any taxonomic rank. The method is in principle deterministic, and widely applied to any type of nucleotide sequences. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tryptophan inhibits bacteriorhodopsin formation in Halorubrum sodomense A01
Authors: Raj S. Mohan , Vatsala T. M.
Published: November 2008

Bacteriorhodopsin (bR) is well recognized for its applied values. We observed that the bottleneck associated with the use of different peptones for bR production was linked to the presence of tryptophan (Trp). Trp at 0.36 mM in the culture medium inhibits bR formation. The results obtained in this study demonstrate that bR content (mg l–1) of Halorubrum sodomense A01 decreased to 2.9 mg l–1 in 0.36 mM Trp compared to control (0.11 mM Trp) where 12.3 mg l–1 of bR was obtained. Our results provide useful information for the design of production conditions for bR to be used in applied settings. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Contribution of cell wall degrading enzymes to pathogenesis of Fusarium graminearum: a review
Authors: Kikot Gisele Eleonora , Hours Roque Alberto , Alconada Teresa Maria
Published: November 2008

Plant‐pathogenic fungi produce an array of extracellular hydrolytic enzymes that enable them to penetrate and infect the host tissue; these enzymes are collectively called cell wall‐degrading enzymes (CWDE). They may contribute to pathogenesis by degrading wax, cuticle and cell walls, thus aiding tissue invasion and pathogen dissemination. Furthermore, they can act as elicitors of host defense reaction.

Fusarium head blight (FHB) is a disease caused principally by Fusarium graminearum on crops, occurring all over the world. Important economic losses on wheat‐growing areas have been registered by altering quality parameters of grains. Significant progress has been made in understanding the infection process from F. graminearum on wheat, based on genomic technologies. The virulence degree of this phytopathogen on crops could arise from differences in the production of extracellular enzymes, factors controlling the establishment of infection.

Fusarium graminearum isolates from different geographical areas have been examined, and a combination of morphological and molecular data allowed the division of fungi in diverse groups, which have been related to the variation in pathogenicity. In most studied cases there is a correlation between the presence of pectic enzymes, disease symptom and virulence, being also their production decisive in the infection process. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bioremediation of chromium(VI) contaminated soil by Streptomyces sp. MC1
Authors: Polti Marta A. , García Roberto O. , Amoroso María J. , Abate Carlos M.
Published: November 2008

This work provides quantitative information on Cr(VI) reduction in soil samples by an indigenous actinomycete. Streptomyces sp. MC1, previously isolated from sugarcane, has shown ability to reduce Cr(VI) in liquid minimal medium. A reduction of 100 and 75% was obtained at initial Cr(VI) concentrations of 5 and 50 mg l–1, respectively, after 48 h of incubation. Bioremediation ability of Streptomyces sp. MC1 was assayed in soil extracts and soil samples. Relative growth of Streptomyces sp. MC1 was 77 and 38% when grown in soil extract with 10 and 50 mg l–1 of Cr(VI), respectively. MC1 was able to reduce 30% of Cr(VI) after 96 h of incubation with 10 mg l–1 of Cr(VI), and reduction coincided with the exponential growth phase at pH 7 and 30 °C.

In soil samples, Streptomyces sp. MC1 was able to reduce up to 94% of the Cr(VI) bioavailability (50 mg kg–1) after 7 d. These results were compared with non‐inoculated soil samples with Cr(VI). Bioremediation activity of Streptomyces sp. MC1 was not inhibited by natural soil microbial flora. Besides, Streptomyces sp. MC1 growth was not inhibited by 50 mg kg–1 of Cr(VI). In contrast to findings obtained by other authors, our results showed almost complete Cr(VI) removal from soil without any previous treatment, and without addition of any substrate and with a normal soil humidity level. These results confirm the Cr(VI)‐contaminated soil bioremediation potential of Streptomyces sp. MC1. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Injection temperature significantly affects in vitro and in vivo performance of collagen‐platelet scaffolds
Authors: Palmer M.P. , Abreu E.L. , Mastrangelo A. , Murray M.M.
Published: November 2008

Collagen‐platelet composites have recently been successfully used as scaffolds to stimulate anterior cruciate ligament (ACL) wound healing in large animal models. These materials are typically kept on ice until use to prevent premature gelation; however, with surgical use, placement of a cold solution then requires up to an hour while the solution comes to body temperature (at which point gelation occurs). Bringing the solution to a higher temperature before injection would likely decrease this intra‐operative wait; however, the effects of this on composite performance are not known. The hypothesis tested here was that increasing the temperature of the gel at the time of injection would significantly decrease the time to gelation, but would not significantly alter the mechanical properties of the composite or its ability to support functional tissue repair. Primary outcome measures included the maximum elastic modulus (stiffness) of the composite in vitro and the in vivo yield load of an ACL transection treated with an injected collagen‐platelet composite. In vitro findings were that injection temperatures over 30°C resulted in a faster visco‐elastic transition; however, the warmed composites had a 50% decrease in their maximum elastic modulus. In vivo studies found that warming the gels prior to injection also resulted in a decrease in the yield load of the healing ACL at 14 weeks. These studies suggest that increasing injection temperature of collagen‐platelet composites results in a decrease in performance of the composite in vitro and in the strength of the healing ligament in vivo and this technique should be used only with great caution. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 964–971, 2009
Effect of pH and NaCl/CaCl2 on the solubility and emulsifying properties of sweet potato protein
Authors: Mu Tai‐Hua , Tan Sze‐Sze , Chen Jing‐Wang , Xue You‐Lin
Published: November 2008

BACKGROUND: The effects of NaCl and CaCl2 on the solubility and emulsifying properties, namely emulsifying activity index (EAI) and emulsion stability index (ESI) of sweet potato proteins (SPPs) at pH 1–10, were investigated.

RESULTS: At lower NaCl (0.1 mol L−1) and CaCl2 (0.05 mol L−1) concentrations, the solubility profiles of the SPPs were very similar to those in distilled water, and the lowest solubility occurred at pH 4. Increased NaCl and CaCl2 concentration resulted in lower SPP solubility in most of the pH studied (P < 0.05). At pH < 3, NaCl improved the EAI of SPP while at pH > 7 it reduced the EAI of the SPP (P < 0.05). Moreover, addition of NaCl also resulted in reduction of ESI of the SPP in most of the pH studied (P < 0.05). On the other hand, the presence of 0.2 mol L−1 CaCl2 rendered the EAI and ESI of the SPPs independent of the influence of pH.

CONCLUSION: The present studies show that pH and salts modified the emulsifying properties of the SPPs, and CaCl2 at a certain concentration could be used to improve the emulsifying properties of the protein. Copyright © 2008 Society of Chemical Industry