bluuebunny/crossref_metadata_2025 huggingface dataset:
Expression of Ammonia Transporters, Rhbg and Rhcg, in Chronic Cyclosporine Nephropathy in Rats
Authors: Lim Sun Woo , Ahn Kyung Ohk , Kim Wan Young , Han Dong He , Li Can , Ghee Jung Yeon , Han Ki Hwan , Kim Hye-Young , Handlogten Mary E. , Kim Jin , Yang Chul Woo , Weiner I. David
Published: September 2008

Background/Aims: Cyclosporine (CsA)-induced renal injury causes renal tubular acidosis. The current study was performed to evaluate the influence of CsA-induced renal injury on the ammonia transporter family members, Rh B-glycoprotein (Rhbg) and Rh C-glycoprotein (Rhcg). Methods: Rats were treated daily for 1 or 4 weeks with vehicle (VH) or CsA. Induction of chronic CsA-induced nephropathy was confirmed by demonstrating impaired renal function and characteristic histopathology. Rhbg and Rhcg expression was evaluated with immunoblot, immunohistochemistry, real-time RT-PCR and electron microscopy. Results: CsA treatment for 4 weeks developed mild metabolic acidosis and decreased urinary ammonia excretion. Rhcg mRNA expression was unchanged in both the cortex and outer medulla, but Rhcg protein expression in the CsA group was significantly reduced in the cortex and outer medulla. There were no significant differences in Rhbg mRNA and protein expression between the CsA and VH group. Conclusion: Long-term treatment with CsA in rats results in decreased urinary ammonia excretion accompanied by decreased expression of Rhcg; these changes are likely to mediate the CsA-induced defect in ammonium excretion in the collecting duct.
Angiographic and Intravascular Ultrasound Assessment of Immediate and 9-Month Efficacy of Percutaneous Transluminal Renal Artery Balloon Angioplasty with Subsequent Brachytherapy in Patients with Renovascular Hypertension
Authors: Lekston Andrzej , Chudek Jerzy , Gąsior Mariusz , Wilczek Krzysztof , Więcek Andrzej , Kokot Franciszek , Gierlotka Marek , Niklewski Tomasz , Fijałkowski Marek , Szyguła-Jurkiewicz Bożena , Wojnicz Roman , Białas Brygida , Osuch Marcin , Maciejewski Bogusław , Poloński Lech
Published: September 2008

Background/Aim: Scarce data exist concerning the long-term effect of renal balloon angioplasty (PTRA) enhanced by intravascular γ-brachytherapy (IVBT) in patients with renovascular hypertension. The aim of this randomized study was to evaluate long-term outcome after PTRA with IVBT in patients with renal artery stenosis. Patients and Methods: 71 patients with renovascular hypertension were randomized into group I (PTRA + IVBT) or group II (PTRA). 9 patients who required stent implantation were excluded. Both baseline and 9-month follow-up quantitative computerized angiography and intravascular ultrasound (IVUS) analysis were performed to assess restenosis. During the 9-month follow-up, 3 patients died – 2 from group I and 1 from group II. Results: The restenosis rate was 16.1% in group I and 32.1% in group II. The 9-month lumen loss in angiography was 1.2 ± 0.7 and 1.7 ± 0.7 mm (p = 0.004) and the area loss (IVUS) was 6.5 ± 4.8 and 10.1 ± 5.6 mm2 in groups I and II, respectively (p = 0.01). eGFR increased both in group I (from 75 ± 22 to 84 ± 31 ml/min/1.73 m2; p < 0.001) and in group II (from 74 ± 23 to 77 ± 23 ml/min/1.73 m2; p = 0.04). Only the diastolic blood pressure in group I decreased significantly (65 ± 17 and 77 ± 18 mm Hg; p = 0.048). The rate of blood pressure normalization was low in both groups (6.1 and 6.9%). Conclusions: IVBT after PTRA with a self-centering source is a safe and effective method for prevention of restenosis in patients with renovascular hypertension.
Downregulation of the Hexokinase II Gene Sensitizes Human Colon Cancer Cells to 5-Fluorouracil
Authors: Peng Qiu-Ping , Zhou Jin-Ming , Zhou Qi , Pan Feng , Zhong Da-Ping , Liang Hou-Jie
Published: September 2008

Background: Extensive trials have indicated that cancer cells with high glycolytic activity exhibit decreased sensitivity to anticancer agents. Moreover, recent research has proven that specific inhibitors of hexokinase (HK) II, a key glycolytic enzyme, may enhance the activity of anticancer drugs. The aim of this study was to investigate the effect and mechanisms of HK II on chemosensitivity of a colon cancer cell line (LoVo) to 5-fluorouracil (5-FU). Methods: HK II gene expression was downregulated by RNA interference in the colon cancer cell line LoVo, which was detected by Western blot analysis. Then the IC50 value of 5-FU was determined in LoVo cells via MTT assay. In addition, cell apoptosis and mitochondrial membrane potential (MMP) were assessed by flow cytometry and caspase-3 activity by its substrate color reaction. Results: In LoVo cells, HK II downregulation resulted in a decreased IC50 value of 5-FU and increased apoptosis. Furthermore, HK II downregulation resulted in a decreased MPP and activation of caspase-3. Conclusion: Our findings suggest that targeting HK II may be beneficial for patients with colon cancer treated with 5-FU.
Extremely fine and uniform microstructure of magnesium AZ91D alloy sheets produced by melt conditioned twin roll casting
Authors: Bian Zan , Bayandorian I. , Zhang H. W. , Scamans G. , Fan Z.
Published: September 2008

Magnesium AZ91D alloy strips consisting of equiaxed grains with a mean size less than 100 μm were fabricated successfully by using the melt conditioned twin roll casting (MC-TRC) process. A melt conditioning by advanced shear technology (MCAST) process for conditioning liquid metals at temperatures either above or below the alloy liquidus using a high shear twin screw mechanism was combined with the twin roll casting (TRC) process to form an innovative technology, namely, the MC-TRC process for casting Al alloy and Mg alloy strips. During the MC-TRC process, liquid melt with a specified temperature is continuously fed into the MCAST machine. By intensive shearing under the high shear rate and high intensity of turbulence, the liquid is transformed into conditioned melt with uniform temperature and composition throughout the whole volume. The conditioned melt is then fed continuously into the twin roll caster for strip production. The experimental results show that the AZ91D MC-TRC strips with different thicknesses have a fine and uniform microstructure. It consists of equiaxed grains with a mean size of 60–70 μm, and also displays extremely uniform grain size and composition throughout the entire cross-section. Investigation also shows that the MC-TRC processes are extremely effective to reduce the formation of defects, particularly the formation of the central line segregations.
Nicknames of Kuwaiti Teenagers
Authors: Haggan Madeline
Published: September 2008

AbstractAlthough nicknaming among teenagers and nicknaming among Arab adults has been studied, nicknaming among Arab teenagers has not. Nicknames of their peers were collected from Kuwaiti teenagers, and Kuwaiti undergraduates judged the nicknames as derogatory, affectionate or neutral. In spite of religious injunctions against the practice, hurtful nicknames were the most common and females were as likely as males to receive uncomplimentary nicknames. Nicknames were also classified as based on appearance or on personality/behaviors, and how they reflected local or western culture. Iraq's invasion of Kuwait and practices arising out of rapid oil-funded development are presented as possible explanations for some of the results.
Going to the Devil
Authors: Abel Ernest L , Kruger Michael L
Published: September 2008

AbstractAfter surveying some of the origins for American placenames associated with the Devil, we determined the prevalence of those placenames including their cognates, e.g., Satan or equivalents in other languages, e.g. Diablo, and related terms such as Hell and its synonyms, e.g. Hades, compared to placenames with angel or Heaven and their equivalents, e.g., archangel, Cielo. We found a much higher prevalence of Devil and Hell placenames attached to natural sites such as mountains and lakes compared to inhabited sites such as cities and schools which were more likely to contain the terms angel or Heaven in their placenames. We also found a considerably higher percentage of Devil and Hell placenames in the western and southern states than in the northeastern and Midwestern states.
Different Strokes for Different Gangs? An Analysis of Capital among Latino and Asian Gang Members
Authors: Pih Kay Kei-Ho , De La Rosa Mario , Rugh Douglas , Mao Kuoray
Published: September 2008

Gang activity and membership were noted to be significantly related to financial rewards. As such, gang membership and gang activity should also be understood from an economic perspective. In this article, Pierre Bourdieu's framework of capital is used to analyze two separate samples of Latino and Asian gang members. Stark contrasts in socioeconomic backgrounds are recorded among the two samples of gang members, and gang membership and activities are also noticeably dissimilar. Accessibility to economic, cultural, and social capital is argued to affect gang membership and activities. The results suggest that the availability of legitimate and illegitimate capital greatly affects the trajectory and the length of gang involvement. Also, gangs provide significant material and social capital for the respondents of the study.
Second-Generation Asian American Pan-Ethnic Identity: Pluralized Meanings of a Racial Label
Authors: Park Jerry Z.
Published: September 2008

Recent research on the collective identity label described as Asian American, which was originally formulated as a political movement symbol, shows only some support among the various Asian ethnic groups that reside in the United States at the beginning of the twenty-first century. Based on a sample of second-generation Asian American student leaders in four public universities, this study provides empirical evidence that the definition of the term Asian American has multiplied as a result of major demographic and cultural factors that have affected the Asian population. These definitions reflect ethnic and religious diversification as well as the model minority stereotype and a cohort identity for the second-generation experience. At the same time, this diversification of definitions is also influenced by two concurrent and interlacing cultural discourses, one that emphasizes the racialized otherness of being “Asian American” and another that emphasizes the cultural diversity within this racial label. Implications for future research and theoretical development follow.
White Normativity: The Cultural Dimensions of Whiteness in a Racially Diverse LGBT Organization
Authors: Ward Jane
Published: September 2008

This article builds on examinations of whiteness in organizations by considering how white normativity—or the often unconscious and invisible ideas and practices that make whiteness appear natural and right—is sustained even in organizations that are attentive to structural factors. Based on two years of ethnographic fieldwork, this article critically examines the racial identity and culture of the Center, a Los Angeles lesbian, gay, bisexual, and transgender (LGBT) organization with a national reputation for multiculturalism, a visible presence of people of color in leadership, and a staff of more than 50 percent people of color. Despite these indicators of racial diversity, the organization also maintained a local reputation among queer people of color as the white LGBT organization in Los Angeles. The author demonstrates that the Center's formal and public attempts to build and proclaim a racially diverse collective identity, along with its reliance on mainstream diversity frames available in the broader environment, became the very practices that employees of color identified as evidence of the white normative culture of the organization.
Dependency, Network Integration, and Development
Authors: Clark Rob
Published: September 2008

Dependency scholars emphasize the harmful effects of economic incorporation for nations residing in the periphery. Conversely, a network perspective of international relations suggests that the major problem peripheral countries face is isolation. Considered together, peripherality implies both resource and partner dependency. Applying dependency and network principles to the world economy and world polity, the author assembles a set of cross-national measures based on international trade relations and membership in international nongovernmental organizations (INGOs). Analyzing a sample of eighty-two developing countries during the 1980–2000 period, the author tests the effects of dependency and network integration on two measures of development: Economic growth and tertiary school expansion. The author finds that dependent integration in trade and INGOs produces economic underdevelopment, while network integration in trade and INGOs positively affects economic growth and educational expansion. The findings broadly confirm dependency and network perspectives, demonstrating the developmental benefits that accrue to core/central actors relative to more dependent/peripheral economies.
Prediction of Conversion Yield in Circulating Fluidised Bed Combustors Using a Two-Dimensional Population Balance
Authors: Nicolella Cristiano , Pratola Federica
Published: September 2008

In combustion applications of fluidised bed reactors, the solid particles are subject to heterogeneous gas-solid chemical reactions, abrasive attrition and other thermal and mechanical processes. The resulting changes in the overall solid phase significantly influence reactor performance. This paper illustrates a particle balance model which accommodates particle distributions dependent on both size and density as well as populations consisting of multiple solids. The proposed model is tested using literature data on coal conversion obtained in a pilot scale circulating fluidised bed combustor. Model simulations give a fair representation of experimental results for different coal ranks and in a range of operating conditions, including varying temperature of combustion, excess of oxygen and superficial gas velocity in the bed.
Collagen fibrillogenesis in tendon development: Current models and regulation of fibril assembly
Authors: Banos Charles C. , Thomas Amelia H. , Kuo Catherine K.
Published: September 2008

Tendons are collagen‐based fibrous tissues that connect and transmit forces from muscle to bone. These tissues, which are high in collagen type I content, have been studied extensively to understand collagen fibrillogenesis. Although the mechanisms have not been fully elucidated, our understanding has continued to progress. Here, we review two prevailing models of collagen fibrillogenesis and discuss the regulation of the process by candidate cellular and extracellular matrix molecules. Although numerous molecules have been implicated in the regulation of collagen fibrillogenesis, we focus on those that have been suggested to be particularly relevant to collagen type I fibril formation during tendon development, including members of the collagen and small leucine‐rich proteoglycan families, as well as other molecules, including scleraxis, cartilage oligomeric matrix protein, and cytoskeletal proteins. Birth Defects Research (Part C) 84:228–244, 2008. © 2008 Wiley‐Liss, Inc.
Quantitative mechanical evaluation and analysis of Drosophila embryos through the stages of embryogenesis
Authors: Shen Yantao , Zhang Rui , Cozen Scott , Xi Ning , Wejinya Uchechukwa C. , Hao Lina
Published: September 2008

The fruit fly Drosophila embryo is one of the most important model organisms in genetics and developmental biology research. To better understand the biomechanical properties involved in Drosophila embryo research, this work presents a mechanical characterization of living Drosophila embryos through the stages of embryogenesis. Measurements of the mechanical forces of Drosophila embryos are implemented using a novel, in situ, and minimally invasive force sensing tool with a resolution in the range of μN. The measurements offer an essential understanding of penetration force profiles during the microinjection of Drosophila embryos. Sequentially quantitative evaluation and analysis of the mechanical properties, such as Young's modulus, stiffness, and mechanical impedance of living Drosophila embryos are performed by extracting the force measurements throughout the stages of embryogenesis. Experimental results illustrate the changing mechanical properties of Drosophila embryos during development, and thus mathematical models are proposed. The evaluation provides a critical step toward better understanding of the biomechanical properties of Drosophila embryos during embryogenesis, and could contribute to more efficient and significant genetic and embryonic development research on Drosophila. Birth Defects Research (Part C) 84:204–214, 2008. © 2008 Wiley‐Liss, Inc.
Sea urchin development: An alternative model for mechanistic understanding of neurodevelopment and neurotoxicity
Authors: Falugi Carla , Lammerding‐Koppel Maria , Aluigi Maria Grazia
Published: September 2008

Echinoderm early developmental stages might supply a good tool for toxicity testing in different fields, ranging from environment to food contamination, and in full respect of the 3Rs objectives (reduction, refinement, and replacement of animal experiments) that will eventually lead to the replacement of high vertebrate animal testing in toxicology. Sea urchin is one of the few organismic models considered by the European Agency for Alternative models. Actually, sea urchin embryonic development has been studied for over a century, and the complex nets of intercellular communications leading to the different events are well known, as well the possibility for environmental molecules and their residuals to interfere with such communications, causing developmental anomalies. In particular, the main goal of toxicologists since several years has been to establish a correlation between the cell‐to‐cell communications occurring during different developmental events and the signals occurring during neurogenesis, with the aim to pursue a mechanistic understanding of these processes and their deviations caused by stressors from different sources. Birth Defects Research (Part C) 84:188–203, 2008. © 2008 Wiley‐Liss, Inc.
Cytology of bronchial associated lymphoid tissue lymphoma
Authors: Chhieng David C.
Published: September 2008

A 69‐year‐old man sought medical care because of persistent cough. Imaging work up revealed multiple nodules involving both lungs. Fine needle aspiration biopsy (FNA) of the right lower lobe mass was performed and revealed atypical alveolar cells in a lymphoid background. The initial cytologic interpretation was “atypical alveolar cells, probably reactive.” The patient underwent wedge resection of the right lower lobe. Intraoperative touch preparation revealed an atypical lymphoid proliferation. Histologic findings revealed multiple nodules of small and medium‐sized lymphocytes replacing the lung parenchyma; lymphoepithelial lesions, and type II pneumocytes hyperplasia were also noted. Flow cytometry demonstrated the presence of a monoclonal B‐cell population. A diagnosis of bronchial associated lymphoid tissue (BALT) lymphoma was established. The patient was treated with rituximab and was disease free 2 years after initial diagnosis. Diagn. Cytopathol. 2008;36:723–728. © 2008 Wiley‐Liss, Inc.
Cytologic feature by squash preparation of pineal parenchyma tumor of intermediate differentiation
Authors: Shimada Keiji , Nakamura Mitsutoshi , Kuga Yoshihiro , Taomoto Katsushi , Ohnishi Hideyuki , Konishi Noboru
Published: September 2008

Pineal parenchyma tumor of intermediate differentiation (PPTID) is a very rare intracranial tumor, and pathological investigation limited to immunohistological and ultrastructural analyses have been published to date. Although intraoperative cytology is one of the important approaches for initial diagnosis in brain tumors, no or little studies on cellular morphology of PPTID have been demonstrated due to its rarity. We report here cytological features of PPTID obtained from stereotactic surgical specimens in a case of 27‐year‐old female manifested by dizziness and diplopia. Brain MRI revealed an unhomogeneously enhanced, large‐sized tumor (56 × 52 × 60 mm) mainly located in the pineal region expanding from the midbrain to superior portion of the cerebellum and the fourth ventricle. Squash cytology showed increased nucleocytoplasmic ratio, hyperchromatic nuclei, and small rosette‐like cell cluster but cellular pleomorphism was mild to moderate and necrotic background was not observed. Histology showed high cellularity, moderate nuclear atypia, and small rosette formation but neither bizarre tumor cells nor necrosis was present. Mitotic counts were very low (less than 1 per 10 high‐power fields) and the MIB‐1 labeling index was relatively high (10.1%). Tumor cells were immunohistochemically positive for neural markers such as synaptophysin, neurospecific enolase but not for glial fibrillary acidic protein or S‐100. In some parts, cells were strongly reactive for neurofilament protein. Taken together, we made a final diagnosis of PPTID. This is the first presentation of cytological analysis by squash preparation that gives an important clue to accurate diagnosis of pineal parenchymal tumor and to understand its malignant potential. Diagn. Cytopathol. 2008;36:749–753. © 2008 Wiley‐Liss, Inc.
Apocrine (cutaneous) sweat gland carcinoma of axilla with signet ring cells: A diagnostic dilemma on fine‐needle aspiration cytology
Authors: Pai Radha R. , Kini Jyoti R. , Achar Chandrayya , Rau Aarathi , Kini Hema
Published: September 2008

Carcinoma arising in the apocrine sweat glands is rare and there are few reports describing the cytological features of this neoplasm. We describe the cytological features of a histologically confirmed apocrine carcinoma occurring in a 55‐year‐old man who presented with an ulcerated mass in the right axilla. Fine‐needle aspiration cytology revealed features of a signet ring adenocarcinoma. The significance of this infrequently encountered neoplasm lies in its potential for diagnostic confusion with more common lesions containing signet ring cells. In an axillary mass lesion, cytological features along with clinical correlation are essential to distinguish primary apocrine carcinoma from mammary neoplasms with signet ring cells and other metastatic adenocarcinomas. Diagn. Cytopathol. 2008;36:739–741. © 2008 Wiley‐Liss, Inc.
Malignant epithelial tumors and hematologic malignancy
Authors: Marković‐Glamočak Mirjana , Sučić Mirna , Ries Sunčica , Gjadrov‐Kuveždić Koraljka , Labar Boris
Published: September 2008

The aim of this study was to analyze the value of cytology in differentiation between malignant epithelial tumor metastases and hematologic malignancy.

The follow‐up of ten (10) patients who underwent diagnosis and treatment of two malignant diseases, i.e. carcinoma and hematologic malignancy, was performed in the 2000–2005 period. The median of age of our patients was 72 years (range: 49–79). Cytological examination included epithelial tumors, lymph nodes and bone marrow standard Pappenheim and immunocytochemically stained smears.

Carcinoma was initially diagnosed in 40% (4/10) patients and hematologic malignancy in 50% (5/10) patients, while both diseases co‐occurred in one patient (1/10).

Most of hematologic malignancy cases (4/10) were diagnosed as lymphoma. Multiple myeloma was diagnosed in 3 out of 10 patients (30%). Individual cases of acute myeloblastic leukemia, chronic lymphocytic leukemia, and chronic myeloid leukemia were diagnosed in the remaining three patients. Most carcinomas were breast cancer (8/10), while prostate and thyroid gland cancer were diagnosed each in one patient, respectively. Diagn. Cytopathol. 2008;36:710–714. © 2008 Wiley‐Liss, Inc.
Increased detection of clue cells in smears from cervical intraepithelial lesions with reduced expression of COX‐2
Authors: Figueiredo Priscila Garcia , Sarian Luis Otávio , Tambascia Julia Kawamura , Simões José Antônio , Rabelo‐Santos Silvia Helena , Discacciati Michelle Garcia , Derchain Sophie
Published: September 2008

The relation between the detection of clue cells in cervical smears of women with CIN and the expression of COX‐2 in these lesions were determined. Samples from 228 women, treated due to CIN and who underwent cervical conization, were obtained. Hybrid Capture II and Pap smear samples were collected immediately before performing conization. Pathological diagnoses were 11 (5%) normal cervix, 35 (15%) CIN1, 31 (14%) CIN2, and 151 (66%) CIN3. COX‐2 immunoreactivity grading on the pathological specimens was based on the German ImmunoReactive score. In cervical smears, 20 fields (40x) were examined, each of them with a minimum count of 10 epithelial cells. When 20% or more of clue cells were detected the sample was considered positive for clue cells. The prevalence of clue cells was similar across histological strata (P = 0.42). Although the expression of COX‐2 did not differ in lesions with varying severities (P = 0.24), there was a negative association between the expression of COX‐2 and the presence of clue cells in Pap smear (OR = 0.4; 95% CI = 0.2–0.9): only 12% of women with moderate and strong expression of COX‐2 had clue cells in their smears, contrasted to 22% of those with negative and weak expression of COX‐2. HPV infection was associated in a borderline manner to the expression of COX‐2 (P = 0.04; OR = 2.3 95% CI = 1.0–5.4). The reduced expression of COX‐2 in CIN specimens may suggest that clue cells interfere with the inflammatory component of the carcinogenic process that lead to CIN. Diagn. Cytopathol. 2008;36:705–709. © 2008 Wiley‐Liss, Inc.
Cytologic features of primary chondroid tumors of bone in crush preparations
Authors: Cabay Robert J. , Reddy Vijaya , David Odile , McIntire Maria , Cimbaluk David , Kasuganti Deepa , Gould Victor , Gattuso Paolo
Published: September 2008

Fine‐needle aspiration biopsy can be utilized effectively in the diagnosis of many bone lesions. Often, these lesions are suspected to be foci of metastatic disease based on clinical and/or radiographic findings. On occasion, microscopic examination of the aspirate yields a diagnosis of a primary neoplasm of chondroid origin. We discuss the cytologic features observed in crush preparations of the most frequently seen primary chondroid tumors of bone and how these lesions can be differentiated from each other and from metastatic lesions. Diagn. Cytopathol. 2008;36:758–761. © 2008 Wiley‐Liss, Inc.
Reactions of nitroxides, part 7: Synthesis of novel nitroxide selenoureas
Authors: Zakrzewski Jerzy , Krawczyk Maria
Published: September 2008

The reactions of 4‐isoselenocyanato‐2,2,6,6‐tetramethylpiperidine‐1‐oxyl with selected amines and lower alcohols give the corresponding novel selenoureas and selenocarbamates, all bearing the nitroxyl moiety. Some of the synthesized selenoureas and selenocarbamates show moderate‐to‐good activity against pathogenic fungi. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:549–556, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20454
Effects of electron‐withdrawing group on the photoisomerization of tetraaryl‐4H‐thiopyran‐1,1‐dioxides
Authors: Jafarpour Farnaz , Ramezani Fatemeh , Pirelahi Hooshang
Published: September 2008

Syntheses and photoisomerization of the new sulfone derivatives, 4,4‐di (p‐trifluoromethylphenyl)‐2,6‐diphenyl‐4H‐thiopyran‐1, 1‐dioxide and 4‐(p‐trifluoromethylphenyl)‐2,4,6‐triphenyl‐4H‐thiopyran‐1,1‐dioxide, have been investigated. The relative molar ratios of the photoproducts are compared with those of 2,4,4,6‐tetraphenyl‐4H‐thiopyran‐1,1‐dioxide as well as electron‐donating substituted 4‐methyl‐2,4,6‐triaryl‐4H‐thiopyran‐1,1‐dioxides as model compounds under identical experimental conditions using 1H NMR spectroscopy. The results observed are discussed on the basis of a triplet excited state di‐π‐methane rearrangement. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:557–561, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20455
Synthesis of new functionalized mono‐ and bisphosphinates with 2,6‐di‐tert‐butyl‐4‐methylphenol fragments
Authors: Prishchenko Andrey A. , Livantsov Mikhail V. , Novikova Olga P. , Livantsova Ludmila I. , Milaeva Elena R.
Published: September 2008

Convenient procedures for the synthesis of functionalized mono‐ and bisphosphinates with 2,6‐di‐tert‐butyl‐4‐methylphenol (ionol) fragments, starting from the available 3,5‐di‐tert‐butyl‐4‐benzaldehyde and its derivatives, are proposed, and some properties of the new phosphorus‐substituted sterically hindered phenols are presented. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:562–568, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20475
A convenient synthesis of novel 7‐phosphonylbenzyl‐2‐substituted pyrazolo[4,3‐e]‐1,2,4‐triazolo[1,5‐c]‐pyrimidine derivatives
Authors: Xiao Lin‐Xia , Li Ke , Meng Liu , Shi De‐Qing
Published: September 2008

A series of pyrazolo[4,3‐e]‐1,2,4‐triazolo‐[1,5‐c]pyrimidine derivatives, bearing phosphonylbenzyl chain in position 7, were conveniently synthesized in an attempt to obtain potent and selective antagonists for the A2Aadenosine receptor or potent pesticide lead compounds. Diethyl[(5‐amino‐4‐cyano‐3‐methylsulfanyl‐pyrazol‐1‐yl)‐benzyl]phospho‐nate (3), which was prepared by the cyclization of diethyl 1‐hydrazinobenzylphosphonate (1) with 2‐[bis(methylthio)methylene]malononitrile (2), reacted with triethyl orthoformate to afford diethyl[(4‐cyano‐5‐ethoxymethyleneamino‐3‐methylsulfanyl‐pyrazol‐1‐yl)‐benzyl]phosphonate (4), which reacted with various acyl hydrazines in refluxing 2‐methoxyethanol to give the target compounds5a–hin good yields. Their structures were confirmed by IR,1H NMR,13C NMR, MS, and elemental analysis. The crystal structure of5ewas determined by single crystal X‐ray diffraction © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:634–638, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20478
Palladium N‐heterocyclic‐carbene‐catalyzed ortho‐arylation of benzaldehyde derivatives
Authors: Dogan Öznur , Gürbüz Nevin , Özdemir İsmail , Çetinkaya Bekir
Published: September 2008

New, sterically demanding 1,3‐dialkylbenzimidazolium salts (2a–c) as N‐heterocyclic‐carbene precursors have been synthesized and characterized. The ortho position of aromatic aldehydes was directly and selectively arylated with aryl chlorides in the presence of a catalytic system prepared in situ from Pd(OAc)2, 1,3‐dialkylbenzimidazolium chlorides (2a–c), and Cs2CO3. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:569–574, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20479
Syntheses and crystal structures of triorganotin(IV) complexes of schiff base derived from 4‐amino‐5‐phenyl‐4H‐1,2,4‐trizole‐3‐thiol
Authors: Ma Chunlin , Wang Qingfeng , Zhang Rufen
Published: September 2008

Four triorganotin complexes of the types [(Ph3Sn)(C15H10FN4S)] (3), [(CH3)3Sn(C15H10FN4S)]n (4), [(Ph3Sn)(C13H9FN4S2)] (5), and [(CH3)3Sn(C13H9FN4S2)]n (6) have been obtained by Schiff base compound 1 (derived from 4‐fluorobenzaldehyde) and compound 2 (derived from thiophene‐2‐carboxadehyde) with triorganotin chloride in the presence of sodium ethoxide. All the complexes were characterized by elemental analysis, IR, and NMR spectroscopies, and X‐ray diffraction analyses, which revealed that complexes 3 and 5 are mononuclear structures, complex 4 and 6 are one‐dimensional zigzag infinite chains via N → Sn and S → Sn bonding interactions. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:583–591, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20481
Cobalt(II) chloride as a novel and efficient catalyst for the synthesis of 1,2,5‐trisubstituted pyrroles under solvent‐free conditions
Authors: De Surya K.
Published: September 2008

CoCl2 is used as an efficient catalyst in the Paal–Knorr condensation of 2,5‐hexadione with primary amines under solvent‐free conditions, leading to the formation of pyrrole derivatives in excellent yield. This method is very easy, rapid, and high yielding reaction for the synthesis N‐substituted pyrrole derivatives. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:592–595, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20482
An efficient green synthesis of xanthenedione derivatives promoted by acidic ionic liquid
Authors: Ma Jing‐Jun , Wang Chun , Wu Qiu‐Hua , Tang Ran‐Xiao , Liu Hai‐Yan , Li Qing
Published: September 2008

Xanthenedione derivatives were prepared through the condensation reaction of aromatic aldehydes with 5,5‐dimethyl‐1,3‐cyclohexanedione promoted by acidic ionic liquid. The reaction time was 20–40 min with the yields between 82.3% and 95.3%. It was shown that the proposed method was fast, high efficient, and environmentally benign. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:609–611, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20486
Improved estimation and visualization of two‐dimensional myocardial strain rate using MR velocity mapping
Authors: Haraldsson Henrik , Wigström Lars , Lundberg Magnus , Bolger Ann F. , Engvall Jan , Ebbers Tino , Kvitting John‐Peder Escobar
Published: September 2008

Purpose

To estimate regional myocardial strain rate, with reduced sensitivity to noise and velocities outside the region of interest, and provide a visualization of the spatial variation of the obtained tensor field within the myocardium.

Materials and Methods

Myocardial velocities were measured using two‐dimensional phase contrast velocity mapping. Velocity gradients were estimated using normalized convolution and the calculated 2D strain rate tensor field was visualized using a glyph representation. Validation utilized a numerical phantom with known strain rate distribution. Strain rate glyph visualizations were created for normal myocardium in both systole and diastole and compared to a patient with an anteroseptal infarction.

Results

In the phantom study the strain rate calculated with normalized convolution showed a very good agreement with the analytic solution, while traditional methods for gradient estimation were shown to be sensitive to both noise and surrounding velocity data. Normal myocardium showed a homogenous strain rate distribution, while a heterogeneous strain rate can be clearly seen in the patient data.

Conclusion

The proposed approach for quantification and visualization of the regional myocardial strain rate can provide an objective measure of regional myocardial contraction and relaxation that may be valuable for the assessment of myocardial heart disease. J. Magn. Reson. Imaging 2008;28:604–611. © 2008 Wiley‐Liss, Inc.
Scan‐rescan variability in perfusion assessment of tumors in MRI using both model and data‐derived arterial input functions
Authors: Ashton Edward , Raunig David , Ng Chaan , Kelcz Fredrick , McShane Teresa , Evelhoch Jeffrey
Published: September 2008

Purpose

To evaluate the contribution to scan‐rescan coefficient of variation (CV) of patient‐specific arterial input function (AIF) measurement in dynamic contrast‐enhanced MRI (DCE‐MRI) data, and to determine whether any advantage or disadvantage to using a data‐derived arterial input function is related to the anatomical location of the target lesion.

Materials and Methods

Two methods are presented for the calculation of perfusion parameters from DCE‐MRI data using a two‐compartment model. The first method makes use of a single‐model AIF across all study data sets, while the second uses an automated process to derive an AIF specific to each data set. Both methods are applied to the analysis of a 25‐subject scan‐rescan study of patients with advanced solid tumors located in either the lungs or the liver. The parameters of interest in this study are the volume transfer constant between arterial plasma and extracellular extravascular space (Ktrans) and the blood‐normalized initial area under the tumor enhancement curve over the first 90 seconds postinjection (IAUCBN90).

Results

The use of a data‐derived AIF reduces the visit‐to‐visit CV in both parameters for liver lesions by approximately 70% while the improvement is less than 20% for lung lesions.

Conclusion

The use of a data‐derived AIF in the analysis of DCE‐MRI data provides a substantial reduction in scan‐rescan CV in the measurement of vascular parameters such asKtransandIAUCBN90. These results show a much larger advantage in the liver than in the lungs. However, this difference is largely driven by a small number of outliers, and may be spurious. J. Magn. Reson. Imaging 2008;28:791–796. © 2008 Wiley‐Liss, Inc.
Visualization of the protective ability of a free radical trapping compound against rat C6 and F98 gliomas with diffusion tensor fiber tractography
Authors: Asanuma Taketoshi , Doblas Sabrina , Tesiram Yasvir A. , Saunders Debra , Cranford Rebecca , Yasui Hironobu , Inanami Osamu , Smith Nataliya , Floyd Robert A. , Kotake Yashige , Towner Rheal A.
Published: September 2008

Purpose

To apply fiber tractography to assess the effect of a possible antiglioma drug, phenyl N‐tert‐butyl nitrone (PBN), on glioma‐affected neuronal fibers. The fiber tractography method was able to differentiate between different tumor types, such as the C6 and F98 rat glioma models.

Materials and Methods

C6 or F98 cells were intracranially injected into the cortex of male Fischer 344 rats. PBN treatment was initiated before or after cell implantation. Tumor growth was monitored with diffusion tensor imaging (DTI) and fiber tractography using diffusion‐weighting gradients in 30 noncolinear directions.

Results

Although proton density‐weighted (PDw) and T2‐weighted (T2w) images did not show any difference between C6 and F98 gliomas without edema, the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) maps were able to discriminate between these two tumor models. Fiber tractography was used to visualize C6 glioma‐induced ischemia of tumor‐surrounding tissues, whereas F98 glioma was found to infiltrate and penetrate into the corpus callosum (CC). During glioma growth, neuronal fibers were found to disappear at the border regions between the tumor and surrounding tissues. PBN treatment was shown to inhibit glioma growth with accompanying changes in the surrounding tissue.

Conclusion

By noninvasively monitoring the degree of neuronal fiber integrity and connectivity with the use of neuronal fiber tractography, we were able to evaluate the protective effect of PBN against invasive glioma growth in rat brains. PBN provided protection of the neuronal fibers against tumor‐induced ischemia and tumor invasion. J. Magn. Reson. Imaging 2008;28:574–587. © 2008 Wiley‐Liss, Inc.
Assessment of fluctuating velocities in disturbed cardiovascular blood flow: In vivo feasibility of generalized phase‐contrast MRI
Authors: Dyverfeldt Petter , Kvitting John‐Peder Escobar , Sigfridsson Andreas , Engvall Jan , Bolger Ann F. , Ebbers Tino
Published: September 2008

Purpose

To evaluate the feasibility of generalized phase‐contrast magnetic resonance imaging (PC‐MRI) for the noninvasive assessment of fluctuating velocities in cardiovascular blood flow.

Materials and Methods

Multidimensional PC‐MRI was used in a generalized manner to map mean flow velocities and intravoxel velocity standard deviation (IVSD) values in one healthy aorta and in three patients with different cardiovascular diseases. The acquired data were used to assess the kinetic energy of both the mean (MKE) and the fluctuating (TKE) velocity field.

Results

In all of the subjects, both mean and fluctuating flow data were successfully acquired. The highest TKE values in the patients were found at sites characterized by abnormal flow conditions. No regional increase in TKE was found in the normal aorta.

Conclusion

PC‐MRI IVSD mapping is able to detect flow abnormalities in a variety of human cardiovascular conditions and shows promise for the quantitative assessment of turbulence. This approach may assist in clarifying the role of disturbed hemodynamics in cardiovascular diseases. J. Magn. Reson. Imaging 2008;28:655–663. © 2008 Wiley‐Liss, Inc.
Feasibility of diffusion‐weighted imaging in the differentiation of metastatic from nonmetastatic lymph nodes: Early experience
Authors: Kim Jeong Kon , Kim Kyoung Ah , Park Bum‐Woo , Kim Namkug , Cho Kyoung‐Sik
Published: September 2008

Purpose

To investigate the feasibility of diffusion‐weighted imaging (DWI) in the differentiation of metastatic from nonmetastatic lymph nodes.

Materials and Methods

In 125 patients who underwent lymph node dissection for uterine cervical cancer, DWI was performed at b value of 0 and 1000 s/mm2. By referring to the surgical maps of the pelvic lymph nodes, the apparent diffusion coefficient (ADC) was compared in the metastatic and nonmetastatic lymph nodes, and receiver‐operating‐characteristics analysis was performed to evaluate the diagnostic performance of the ADC in differentiating metastatic from nonmetastatic lymph nodes.

Results

The ADC were significantly lower in the metastatic lymph nodes (0.7651 × 10−3 mm2/s ± 0.1137) than in the nonmetastatic lymph nodes (1.0021 × 10−3 mm2/s ± 0.1859; P < 0.001). The area‐under‐the‐curve of ADC for differentiating metastatic from nonmetastatic lymph nodes, was 0.902. The sensitivity and specificity of ADC for differentiating metastatic from nonmetastatic lymph nodes, were 87% for the ADC and 80%, respectively.

Conclusion

DWI is feasible for differentiating metastatic from nonmetastatic lymph nodes in patients with uterine cervical cancer. J. Magn. Reson. Imaging 2008;28:714–719. © 2008 Wiley‐Liss, Inc.
Complex threshold method for identifying pixels that contain predominantly noise in magnetic resonance images
Authors: Pandian Daniel S.J. , Ciulla Carlo , Haacke E. Mark , Jiang Jing , Ayaz Muhammad
Published: September 2008

Purpose

To create a robust means to remove noise pixels using complex data.

Materials and Methods

A receiver operating characteristic (ROC) curve was used to determine the appropriate choice of magnitude and phase thresholds as well as connectivity values to determine what pixels represent noise in the image. To fine‐tune the results, a spike removal and hole replacement operator is applied to reduce Type I error and remove small islands of noise.

Results

The use of phase information improves the magnitude‐only thresholding approach by further recognizing pixels that contain only noise. The performance of the method is enhanced using local connectivity of magnitude and phase data. An ROC analysis on simulated data shows that the Type I and Type II errors are less than 10−4 and 10−3, respectively, without connectivity and 0 and 10−3, respectively, with connectivity for a signal‐to‐noise ratio (SNR) of 3:1 or higher.

Conclusion

The joint use of both magnitude and phase images helps to improve the removal of noise points in magnetic resonance images. This can prove useful in automating the visualization of phase images without the highly distractive phase noise in noise regions. Also, it is useful in susceptibility weighted imaging when taking the minimum intensity projections of variably sized regions. J. Magn. Reson. Imaging 2008;28:727–735. © 2008 Wiley‐Liss, Inc.
Arterial visualization by contrast‐enhanced moving‐table MR angiography: Crossover comparison of 0.1 and 0.2 mmol/kg doses of meglumine gadopentetate in normal volunteers
Authors: Hayashi Hiromitsu , Yuasa Yuji , Amano Yasuo , Tanimoto Akihiro , Saito Yoko , Yoshioka Kunihiro , Kita Miho , Kumazaki Tatsuo , Hiramatsu Kyoichi
Published: September 2008

Purpose

To determine the appropriate dose of contrast medium for moving‐table MR angiography (MT‐MRA) from the abdominal aorta to the ankle by comparing visualization with different doses of meglumine gadopentetate (Gd‐DTPA) administered in crossover fashion to normal volunteers.

Materials and Methods

Twelve healthy adults underwent imaging after crossover administration of 0.1 and 0.2 mmol/kg of Gd‐DTPA in random order. Continuous MT‐MRA was performed with a fast 3D spoiled gradient echo sequence without parallel imaging technique. Visualization was evaluated in a total of 252 arteries by three blinded readers who independently rated arterial visualization using a 5‐grade scale. Signal intensity was determined and the blood concentration of Gd‐DTPA was estimated.

Results

Arterial visualization in the lower leg region was significantly better with a dose of 0.2 mmol/kg than with 0.1 mmol/kg (P < 0.001). For all regions assessed the estimated blood Gd‐DTPA level was significantly higher with 0.2 mmol/kg than with 0.1 mmol/kg (abdominal aorta, P = 0.030; superficial femoral artery, P < 0.001; posterior tibial artery, P = 0.039). The vascular signal enhancement ratio and artery‐to‐muscle signal ratio were significantly higher in the upper leg and lower leg regions at 0.2 mmol/kg.

Conclusion

With continuous MT‐MRA imaging from the abdomen to the ankle in normal volunteers, better arterial visualization and superior contrast were achieved with 0.2 mmol/kg of Gd‐DTPA. J. Magn. Reson. Imaging 2008;28:783–790. © 2008 Wiley‐Liss, Inc.
Magnetic resonance detection of kidney iron deposition in sickle cell disease: A marker of chronic hemolysis
Authors: Schein Aaron , Enriquez Cathleen , Coates Thomas D. , Wood John C.
Published: September 2008

Purpose

To study the pattern, etiology, and significance of renal iron accumulation in chronically transfused sickle cell disease (SCD) and thalassemia major (TM) patients using magnetic resonance imaging (MRI).

Materials and Methods

Magnetic resonance imaging (MRI) was performed in 75 SCD patients, 73 TM patients, and 16 healthy controls. Multiecho gradient echo protocols were used to measure T2* reciprocals (R2*) in the kidney, liver, and heart. Kidney R2* was compared to tissue iron estimates, serum iron markers, and surrogates of intravascular hemolysis by univariate regression.

Results

Mean R2* in SCD patients was 55.3 ± 45.3 Hz, compared with 22.1 ± 11 Hz in TM patients and 21.3 ± 5.8 Hz in control subjects (P < 0.001). Kidney R2* decreased with advancing age (R2 = 0.09, P < 0.02). Kidney R2* correlated strongly with increased serum lactate dehydrogenase levels found in SCD (R2 = 0.55, P < 0.001), but was independent of hepatic iron concentration and cardiac R2*. Kidney R2* did not correlate with blood pressure, creatinine, cardiac index, or right and left ejection fraction.

Conclusion

Intravascular hemolysis, not chronic transfusion, causes renal hemosiderosis in SCD. Prospective trials are necessary to determine whether kidney R2* is a biomarker for hemolysis‐mediated vascular complications in SCD. J. Magn. Reson. Imaging 2008;28:698–704. © 2008 Wiley‐Liss, Inc.