bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatment of RO brine–towards sustainable water reclamation practice
Authors: Ng H. Y. , Lee L. Y. , Ong S. L. , Tao G. , Viawanath B. , Kekre K. , Lay W. , Seah H.
Published: September 2008

Treatment and disposal of RO brine is an important part in sustaining the water reclamation practice. RO brine generated from water reclamation contains high concentration of organic and inorganic compounds. Cost-effective technologies for treatment of RO brine are still relatively unexplored. Thus, this study aim to determine a feasible treatment process for removal of both organic and inorganic compounds in RO brine generated from NEWater production. The proposed treatment consists of biological activated carbon (BAC) column followed by capacitive deionization (CDI) process for organic and inorganic removals, respectively. Preliminary bench-scale study demonstrated about 20% TOC removal efficiency was achieved using BAC at 40 mins empty bed contact time (EBCT) while the CDI process was able to remove more than 90% conductivity reducing it from 2.19 mS/cm to only about 164 μS/cm. More than 90% cations and anions in the BAC effluent were removed using CDI process. In addition, TOC and TN removals of 78% and 91%, respectively were also attained through this process. About 90% water recovery was achieved. This process shows the potential of increased water recovery in the reclamation process while volume for disposal can be further minimized. Further studies on the sustainable operation and process optimization are ongoing.
Reducing operating costs for struvite formation with a carbon dioxide stripper
Authors: Fattah K. P. , Sabrina N. , Mavinic D. S. , Koch F. A.
Published: September 2008

One of the major operational costs of phosphorus recovery as struvite is the cost of caustic chemical that is added to maintain a desired level of operative pH. A study was conducted at the Lulu Island Wastewater Treatment Plant (LIWWTP), Richmond, BC, using a struvite crystallizer and a cascade stripper designed at the University of British Columbia (UBC). The stripper was tested under different operating conditions to determine the effectiveness of CO2 stripping in increasing the pH of the water matrix and thereby reducing caustic chemical use. This reduction is expected to reduce the operational costs of struvite production. Throughout the project, a high percentage (90%) of phosphorus removal was achieved under each condition. The cascade stripper was very effective in saving caustic usage, ranging from 35% to 86%, depending on the operating conditions. However, the stripper showed relatively poor performance regarding ammonia stripping.
The basal chordate amphioxus as a simple model for elucidating developmental mechanisms in vertebrates
Authors: Koop Demian , Holland Linda Z.
Published: September 2008

This review examines the basal chordate, amphioxus, as a simple model for providing insights into the development and evolution of the vertebrates, with which it shares many features, including a pharynx perforated with gill slits, a dorsal nerve cord, segmented muscles, and a notochord. Conversely, amphioxus is simpler than vertebrates in lacking neural crest and paired cephalic sensory organs. Amphioxus embryos are less derived than those of vertebrates, because it lacks large quantities of yolk and/or extra‐embryonic tissues. Embryogenesis involves only a simple folding of tissue layers. In addition, the amphioxus genome lacks the large‐scale gene duplications of vertebrates. However, in spite of the comparative simplicity of amphioxus, its developmental mechanisms are proving to be highly conserved with those of vertebrates. Thus, studies of amphioxus development can shed light on similar, but more complex, development of vertebrates. Such studies are especially interesting for their insights into the genetic basis of craniofacial birth defects in humans. Birth Defects Research (Part C) 84:175–187, 2008. © 2008 Wiley‐Liss, Inc.
Chicken embryo as a model for regenerative medicine
Authors: Coleman Cynthia M.
Published: September 2008

Although the chick embryo, including its extraembryonic membranes, has long been used as a model for developmental biology, its potential as a model for the repair and regeneration of adult human tissues is often overlooked. The chick offers a well‐defined profile of intercellular and intracellular signaling pathways regulating the development of nearly every organ system in conjunction with great flexibility for chimeric and transgenic experiments. Depending upon the system of interest, the chick can either directly reflect the human condition, as in spinal cord repair or in chorioallantoic membrane wound healing, and therefore act as an in vivo model for repair, or mirror our aspired therapy as in limb generation or otic restoration and therefore act as our guide. With these unique opportunities, the chick embryo is certainly a model to be considered when aiming to develop a regenerative therapy for human applications. Birth Defects Research (Part C) 84:245–256, 2008. © 2008 Wiley‐Liss, Inc.
Cytologic diagnosis of metastatic seminoma to the prostate and urinary bladder: A case report
Authors: Alsharif Mariam , Aslan Deniz L. , Jessurun Jose , Gulbahce H. Evin , Pambuccian Stefan E.
Published: September 2008

A 42‐year‐old man presented with severe abdominal pain, constipation, and hematuria. The patient had a history of seminoma treated by chemotherapy followed by bilateral orchiectomy and retroperitoneal lymph node dissection 16 years earlier. A computed tomography (CT) scan showed a 8.0 × 6.0 × 5.0 cm mass in the retrovesical space, encompassing the left side of his proximal bladder, the prostate, and the rectum. A urine cytologic specimen showed loosely cohesive cell clusters composed of highly atypical large cells and occasional large, single cells with macronucleoli present in a background of mainly lymphocytes and histiocytes was diagnosed as recurrent seminoma. Prostate biopsies showed extensively necrotic seminoma with accompanying granulomatous reaction. The tumor cells were immunoreactive for c‐kit (CD117), placental‐like alkaline phosphatase (PLAP), D2‐40, and OCT4. To our knowledge, this is the second report on urine cytology of metastatic seminoma. Diagn. Cytopathol. 2008;36:734–738. © 2008 Wiley‐Liss, Inc.
Metastatic hepatocellular carcinoma with CD138 positivity: An unusual mimic of multiple myeloma?
Authors: Ramalingam Preetha , Adeagbo Bamidele , Bollag Ronie , Lee Jeffrey , Reid‐Nicholson Michelle
Published: September 2008

CD138 is a monoclonal anti‐syndecan‐1 antibody that is often used to identify plasma cells in the bone marrow of patients with multiple myeloma (MM). Several carcinomas may also express CD138 including prostate, colon, renal cell, and hepatocellular carcinoma (HCC). We report a case of metastatic HCC that presented as a soft tissue mass on the back of a 67‐year‐old male. Based on the clinical and radiologic findings, MM was strongly suspected. In addition, fine‐needle aspiration biopsy (FNAB) of the mass revealed neoplastic cells that were positive for CD138, both by immunohistochemistry (IHC) and flow cytometry. The cytomorphologic features however did not support a diagnosis of MM, but were consistent with metastatic HCC. Our case highlights the potential problems that may arise by over‐reliance on IHC and flow cytometry. Careful morphologic assessment as well as clinical and radiologic correlation are very important when evaluating any CD138‐positive neoplasm. This approach should improve diagnostic accuracy and reduce the risk of erroneous interpretation of aberrant IHC results. In addition, we examined the expression of CD138 in known cases of HCC. Diagn. Cytopathol. 2008;36:742–748. © 2008 Wiley‐Liss, Inc.
Fine‐needle aspiration biopsy of metastatic malignant melanoma resembling a malignant peripheral nerve sheath tumor
Authors: Bardarov Svetoslav , Michael Claire W. , Lucas David , Pang Yijun , Pu Robert T.
Published: September 2008

We report a case of metastatic malignant melanoma resembling a malignant peripheral sheath tumor, which posed a significant diagnostic challenge. The patient is a 76‐year‐old male, who presented in the emergency room with bilateral chest pain exacerbated by inspiration. The pain was present for 3 week and was not exacerbated by physical exercise. The diagnostic workup revealed bilateral parenchymal pulmonary infiltrates. The CT‐scan guided fine‐needle aspiration and the core biopsies of the largest pulmonary lesion revealed high‐grade spindle cell neoplasm with individual cell apoptosis and necrosis. The immunohistochemical profile on the cell block showed that the cells are positive for Vimentin. The S‐100 stain showed only focal positivity. The immunohistochemical stains for HMB45, Melan A, pancytokeratin, and smooth muscle actin were negative. Five years ago the patient was diagnosed with melanoma on the back with Clark level of IV. The melanoma was excised with clear margins and sentinel lymph nodes were negative. Careful examination of patient's previous slides revealed an area of spindle cell melanoma adjacent to a nodular type melanoma. Based on the patient's previous history, current clinico‐pathologic presentation and immunohistochemical profile, the diagnosis of metastatic malignant melanoma resembling peripheral nerve sheath tumor was favored over the diagnosis of metastatic malignant spindle cell neoplasm of unknown primary site, which by itself is very rare clinical scenario. Diagn. Cytopathol. 2008;36:754–757. © 2008 Wiley‐Liss, Inc.
Liesegang rings in fine needle aspirate of breast cysts with predominance of apocrine cells: A study of 14 cases
Authors: Gupta Raj K.
Published: September 2008

Fine needle aspirate (FNA) from 14 cases (age range 17–84 years), with Liesegang rings (LR's) in breast cysts seen over a period of 26 years comprised the material of this study from more than 38,000 FNA's of the breast which had been done for a variety of breast lesions. In six of the 14 cases, the aspirate was obtained under ultrasound guidance whereas in the remaining cases it was collected from a palpable lesion. The aspiration was performed using a 22 gauge needle and the syringe and needle contents were washed in a cytology container with 30% ethyl alcohol in physiologic saline. The cytologic preparations from half of the sample were made on a 5 micron Schleicher and Schuell filter and stained by Papanicolaou method whereas from the remainder of the sample a cell block was made and sections cut, stained with hematoxylin‐eosin (H&E) and used for immunohistochemical study.

Filter preparations and cell blocks revealed cyanophilic, spherical, ring‐like structures of various sizes and shape mostly with double walls, and striations with amorphous material in the lumen and under polarized light were nonrefractile. Seen also were several apocrine cells and some macrophages and the LR's were found to be negative on immunostains for EMA and CK, and a panel of other special stains (Table I). Since LR's can be mistaken for ova, larvae, or parasites, it is important to be aware of their potential presence in aspirate samples of breast cysts to avoid a misdiagnosis. The exact mechanism of formation of LR's is not fully understood and certain views as proposed are discussed in this presentation. Diagn. Cytopathol. 2008;36:701–704. © 2008 Wiley‐Liss, Inc.
Diagnosis of sinus histiocytosis with massive lymphadenopathy (Rosai‐Dorfman disease) by fine needle aspiration cytology
Authors: Kumar Bipin , Karki Smriti , Paudyal Punam
Published: September 2008

Sinus histiocytosis with massive lymphadenopathy (Rosai‐Dorfman disease) is a rare benign disease of unknown etiology presenting with massive lymphadenopathy. We report four cases of this disease retrieved from the archives of cytopathology laboratory, BPKIHS, Dharan, Nepal, during the period of January 2002 to October 2007. The cytologic morphology revealed lymphocytes, plasma cells, and single to multinucleated histiocytes with well preserved lymphocytes in their cytoplasm (emperipolesis or lymphophagocytosis). It is concluded that FNAC is a useful and reliable tool for the diagnosis of sinus histiocytosis with massive lymphadenopathy (Rosai‐Dorfman disease) and biopsy can be avoided in these patients, thereby reducing patient inconvenience and health care cost. Diagn. Cytopathol. 2008;36:691–695. © 2008 Wiley‐Liss, Inc.
Cytological detection of lymphoma in Douglas aspirate
Authors: Ljubić Nives , Sučić Mirna , Vasilj Ankica , Lang Nada , Dominis Mara , Batinica Anita Grgurević , Jurković Ljiljanka , Šiftar Zoran
Published: September 2008

Except in primary effusion lymphoma (PEL), serous effusions with lymphomatous cells in non‐Hodgkin lymphoma (NHL) are not frequently seen as first manifestation of disease. In NHL lymphoplasmacytic lymphoma (LPL) the spleen, lymph nodes, and bone marrow are frequently sites of disease and this type of NHL is usually associated with a serum paraprotein of IgM type accompanied by the clinical syndrome of Waldenström macroglobulinemia. Our patient with NHL LPL type presented in this report had less frequently seen involvement of gastrointestinal tract and clinically was first manifested as effusion in Douglas space. Cytological evaluation as well immunoanalyses of effusion in such cases is essential, and various ancillary studies, because of differential diagnostic problems of lymphomas in serous effusions, first include reactive lymphocytoses and small round‐cell tumors (SRCT). In our patient, cytology of effusion revealed cytomorphologically atypical lymphomatous cells with plasmocytoid differentiation. Immunocytochemical and flow cytometry analysis confirmed lymphoid cell differentiation and pathohistological diagnosis of CD20+ LPL was set after pathohistological analysis of resected ileum. Diagn. Cytopathol. 2008;36:729–733. © 2008 Wiley‐Liss, Inc.
Syntheses, Structures and Reactivities of [CpTc(CO)3X]+ and [CpRe(CO)3X]+ (Eur. J. Inorg. Chem. 27/2008)
Authors: Zobi Fabio , Spingler Bernhard , Alberto Roger
Published: September 2008

The cover picture shows new aspects of [Cp*Re(CO)3Br]+ and [Cp*Tc(CO)3Br]+ chemistry. High‐yield preparation of these basic complexes (especially for 999Tc) enabled a comparative exploration of the respective chemistries in water and organic solvents. The Lewis acidic ReIII and TcIII centres activate the CO ligands for directed substitutions and nucleophilic attack. The reaction with CH3OH gave a methyl formate complex which reduced to [Cp*M(CO)3] under acidic conditions. IR spectroscopy and kinetic studies with 13C‐labelled formate revealed the source for CO in [Cp*Re(CO)3]. Shown are the different colours of homologous Re and Tc complexes against a background of the Zurich lake area. The reactivity of the title compounds with alcohols implies potential for targeted inorganic medicinal chemistry if the OH group is pendent to a (radio)pharmaceutical. Details are discussed in the article by R. Alberto et al. on p. 4205 ff. We thank Dr. F. Wild for designing this picture.
An efficient chemo‐ and stereoselective synthesis of enaminones and enaminoesters using (bromodimethyl)sulfonium bromide under solvent‐free conditions
Authors: Das Biswanath , Kanth Boddu Shashi , Majhi Anjoy , Reddy Kongara Ravinder
Published: September 2008

(Bromodimethyl)sulfonium bromide has efficiently been employed for chemo‐ and stereoselective conversions of β‐dicarbonyl compounds into β‐enaminones and β‐enaminoesters by a treatment with amines at room temperature under solvent‐free conditions. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:630–633, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20477
Stereoselective synthesis of enantiopure cyclic α‐aminophosphonic acids: Direct observation of inversion at phosphorus in phosphonate ester silyldealkylation by bromotrimethylsilane
Authors: Alfonsov Vladimir A. , McKenna Charles E. , Bayandina Evgenia V. , Kashemirov Boris A. , Yarmieva Liliya N. , Punegova Lyudmila N. , Kataeva Olga N.
Published: September 2008

The paper describes a simple, direct synthesis of enantiopure cyclic α‐aminophosphonic acids on the basis of silyldealkylation and followed by hydrolysis of the parent diastereoisomeric cyclic 1,4,2‐oxazaphosphorines, which have been obtained by intramolecular stereospecific nucleophilic addition of phosphites to imines. In this approach, the high diastereoselectivity of the stereocontrolling penultimate step is preserved by conversion of the intermediate ester to the final phosphonic acid under very mild, nonracemizing conditions. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:575–582, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20480
An efficient and green method for the synthesis of N‐phosphoramino o‐hydroxylphenyl α‐aminophosphonic monoesters
Authors: Zhang Jianfeng , Wang Yadan , Cui Zhanwei , Wang Fei , Miao Zhiwei , Chen Ruyu
Published: September 2008

An efficient and green method to the synthesis of N‐protected o‐hydroxylphenyl α‐amino‐alkylphosphonic monoesters is described. It consists of the three‐component Mannich‐type reaction of phosphoramides, carbonyl compounds (aldehydes or ketones), and 2‐chlorobenzo[1,3,2] diox‐aphospholes under solvent‐free and catalyst‐free conditions, followed by hydrolysis. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:596–601, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20483
Synthesis and fungicidal activity of O‐alkyl O‐aryl O‐2‐(stearamido)ethyl phosphates
Authors: Han Liang , Gao Jian‐Rong , Li Zheng‐Ming
Published: September 2008

N‐stearoylethanolamine (NAE18:0) was reacted with O‐alkyl O‐aryl chlorophosphate and a series of O‐alkyl O‐aryl O‐2‐(stearamido)ethyl phosphates were synthesized to explore their antifungal activity. Compared with parent NAE18:0, title compounds without substitution or with methyl substitution on a benzene ring exhibited improved antifungal activity. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:602–608, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20485
A novel stereoselective synthesis of (2Z)‐2‐arylsulfanylallylic alcohols by tin–lithium exchange of (E)‐α‐stannylvinyl sulfides
Authors: Xu Yaping , Hao Wenyan , Wang Dong , Cai Mingzhong
Published: September 2008

Tin–lithium exchange reaction of (E)‐α‐stannylvinyl sulfides 1 with n‐butyllithium gave (Z)‐α‐arylsulfanylvinyllithiums 2, which reacted with aldehydes or ketones 3 to afford stereoselectively (2Z)‐2‐arylsulfanylallylic alcohols 4 in good to high yields. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:639–643, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20487
Organotin(IV) esters of (E)‐3‐furanyl‐2‐phenyl‐2‐propenoic acid: Synthesis, investigation of the coordination modes by IR, multinuclear NMR (1H, 13C, 119Sn) and In Vitro biological studies
Authors: Sadiq‐ur‐Rehman  , Ali Saqib , Shahzadi Saira
Published: September 2008

Complexes [Me2SnL2 (I), Me3SnL (II), Et2SnL2 (III), n‐Bu2SnL2 (IV), n‐Bu3SnL (V), n‐Oct2SnL2 (VI)], where L is (E)‐3‐furanyl‐2‐phenyl‐2‐propenoate, have been synthesized and structurally characterized by vibrational and NMR (1H, 13C and 119Sn) spectroscopic techniques in combination with mass spectrometric and elemental analyses. The IR data indicate that in both the di‐ and triorganotin(IV) carboxylates the ligand moiety COO acts as a bidentate group in the solid state. The 119Sn NMR spectroscopic data, 1J[119Sn,13C] and 2J[119Sn, 1H], coupling constants show a four‐coordinated environment around the tin atom in triorganotin(IV) and five‐coordinated in diorganotin(IV) carboxylates in noncoordinating solvents. The complexes have been screened against bacteria, fungi, and brine‐shrimp larvae to assess their biological activity. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:612–620, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20488
A new convenient way to synthesize 1,3,4‐thiadiazol‐2‐yl urea derivatives under microwave irradiation
Authors: Li Kejian , Chen Wenbin
Published: September 2008

A simple and efficient method was developed for the synthesis of 1‐(substituted)‐3‐(5‐(substituted)‐1,3,4‐thiadiazol‐2‐yl) ureas from heterocyclic amino compounds and phenyl‐5‐(pyridine‐3‐yl)‐1,3,4‐thiadiazol‐2‐ylcarbamate(2) or phenyl‐5‐(trifluoro‐methyl)‐1,3,4‐thiadiazol‐2‐ylcarbamate(5) under solvent conditions using microwave irradiation. The products were obtained in satisfactory yield as we expected. The reactions can be realized by conventional heating, but we find that the condition of microwave is better according to the reaction time. New 1‐(substituted)‐3‐(5‐(substituted)‐1,3,4‐thiadiazol‐2‐yl) urea derivatives are reported. The products were characterized by1H NMR, ESI‐MS, and Elemental analysis. The crystal structure of compound6hwas determined by X‐ray single crystal diffraction. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:621–629, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20489
Bismuth‐catalyzed cyclization of amino‐1,6‐enynes
Authors: Komeyama Kimihiro , Miyagi Motoyoshi , Takaki Ken
Published: September 2008

Bi(OTf)3 effectively catalyzed the cyclization of amino‐1,6‐enynes, leading to bicyclic amine and cyclopentadienyl amino compounds. The selectivity of the products depends on the substitution pattern of the olefinic moiety. 19F NMR trace experiment of the reaction and other results indicate a novel alkynophilicity of the bismuth species. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:644–648, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20490
2D free‐breathing dual navigator‐gated cardiac function validated against the 2D breath‐hold acquisition
Authors: Peters Dana C. , Nezafat Reza , Eggers Holger , Stehning Christian , Manning Warren J.
Published: September 2008

Purpose

To develop and validate a free‐breathing cardiac cine acquisition, with potential to simplify cardiac MR studies, provide registered slices, and increase spatial resolution.

Materials and Methods

A 2D free‐breathing (FB) navigator‐gated cine radial acquisition for cardiac function was developed that used two navigators (one placed prior to the QRS, and another 500 msec after the QRS complex, after systole) to provide complete motion‐compensated assessment of systole, without loss of end‐diastole. Eleven subjects were studied.

Results

The 2D FB method provided results visually and quantitatively similar to the 2D breath‐hold (BH) methods. Comparison of volumes measured with FB to those measured by standard 2D BH cine resulted in mean bias ± 2 standard deviations of 1.0 mL ± 13.7 mL, 1.1 mL ± 7.6 mL, 3.0 g ± 18.8 g, and 0.3% ± 2.5%, for end‐diastolic volume, end‐systolic volume, left ventricular (LV) mass, and ejection fraction, respectively. Slice misregistration was identified in four (36%) of the BH studies, but none (0%) of the FB studies. In subjects with slice misregistration, there was greater discordance in LV volume measurements (P < 0.05 for end‐diastolic mass).

Conclusion

The FB cine acquisition provided results qualitatively and quantitatively similar to 2D BH methods with improved slice registration. J. Magn. Reson. Imaging 2008;28:773–777. © 2008 Wiley‐Liss, Inc.
Noninvasive estimation of hepatic steatosis using plain CT vs. Chemical‐shift MR imaging: Significance for living donors
Authors: Yoshimitsu Kengo , Kuroda Yousuke , Nakamuta Makoto , Taketomi Akinobu , Irie Hiroyuki , Tajima Tsuyoshi , Hirakawa Masakazu , Ishigami Kousei , Ushijima Yasuhiro , Yamada Tomomi , Honda Hiroshi
Published: September 2008

Purpose

To compare plain computed tomography (CT) and chemical‐shift MR imaging (CSI) for establishing a noninvasive method to estimate the degree of steatosis.

Materials and Methods

A total of 58 patients who had histological proof of liver tissue and underwent CT and/or CSI within two weeks, were studied. They consisted of 38 living donor candidates and 20 liver surgery patients without hepatitis or cirrhosis. The CT index (CTI) and MR index (MRI) were defined and correlated to histological grades of steatosis. Correlation was also performed exclusively for mild steatosis (grades 0–2).

Results

Both plain CT (ρ = 0.74, P < 0.0001) and CSI (ρ = 0.83, P < 0.0001) had good correlation with histological grades of steatosis, showing no significant difference between them. For mild steatosis, CSI (ρ = 0.77, P < 0.0001) had better correlation than CT (ρ = 0.49, P = 0.001) (P = 0.049). Accuracy in differentiation between grade 0–1 vs. grade 2–4 steatosis was 85% using a CTI >6, and 91% using an MRI <0.03 as criteria. That between grade 0–2 and grade 3–4 was 91% using a CTI >–8 and 88% using an MRI <0.25 as criteria.

Conclusion

Both plain CT and CSI were useful in estimating the degree of steatosis but CSI was superior to CT in differentiating mild steatosis. These indices may at least partially replace percutaneous biopsy in evaluating grades of steatosis for living donors. J. Magn. Reson. Imaging 2008;28:678–684. © 2008 Wiley‐Liss, Inc.
Diffusion tensor imaging of the auditory pathway in sensorineural hearing loss: Changes in radial diffusivity and diffusion anisotropy
Authors: Lin YuChun , Wang JiunJie , Wu CheMing , Wai YauYau , Yu JenFang , Ng ShuHang
Published: September 2008

Purpose

To prospectively compare diffusion tensor imaging (DTI) measures of axial diffusivity (λ∥), radial diffusivity (λ⟂), mean diffusivity (MD), and fractional anisotropy (FA) along the auditory pathway of patients with sensorineural hearing loss (SNHL) and normal controls.

Materials and Methods

In 37 individuals with SNHL and 10 healthy controls, two regions of interest (ROIs) positioned along the auditory pathway—the lateral lemniscus (LL) and the inferior colliculus (IC)—were investigated bilaterally using diffusion tensor imaging at 3 T. SNHL patients were divided into three groups: patients with bilateral hearing loss, patients with unilateral hearing loss, and patients with partial hearing loss. DTI measures (λ∥, λ⟂, MD, FA) of both ROIs were determined in all subjects.

Results

The FA value was reduced and the λ⟂ was increased both at the lateral lemniscus and the inferior colliculus of patients with SNHL compared with controls. Similar changes were seen between the ipsilateral and contralateral LL and IC for patients of unilateral profound hearing loss. No changes were observed in any other parameters.

Conclusion

In SNHL patients DTI showed a high radial diffusivity that consequently led to a decreased fractional anisotropy in the LL and the IC. J. Magn. Reson. Imaging 2008;28:598–603. © 2008 Wiley‐Liss, Inc.
Diffusion‐weighted imaging of the liver: Optimizing b value for the detection and characterization of benign and malignant hepatic lesions
Authors: Goshima Satoshi , Kanematsu Masayuki , Kondo Hiroshi , Yokoyama Ryujiro , Kajita Kimihiro , Tsuge Yusuke , Watanabe Haruo , Shiratori Yoshimune , Onozuka Minoru , Moriyama Noriyuki
Published: September 2008

Purpose

To determine the optimal b values required for diffusion‐weighted (DW) imaging of the liver in the detection and characterization of benign and malignant hepatic lesions.

Materials and Methods

MR images obtained in 76 patients including 28 malignant hepatic lesions (21 hepatocellular carcinomas and 7 metastases) and 27 benign lesions (12 hemangiomas and 15 cysts) were reviewed. DW‐echo planner images (EPIs; b values with100, 200, 400, and 800 s/mm2) were reviewed solely first, and then with T2‐weighted EPIs (b = 0 s/mm2).

Results

Sensitivity for malignant lesions (74%) was highest on DW‐EPIs with b value of 100 s/mm2 and T2‐weighted EPIs combined (P < 0.05), and sensitivity for benign lesions (87%) was highest on DW‐EPIs with b value of 800 s/mm2 and T2‐weighted EPIs (P < 0.05). Specificities were comparably high for all sequences. The Az values for malignant lesions were 0.94, 0.90, 0.87, and 0.89, and those for benign lesions were 0.91, 0.89, 0.87, and 0.94 on DW‐EPIs with b values of 100, 200, 400, and 800 and T2‐weighted EPIs combined, respectively. Hepatic cysts were clearly distinguished with the cutoff ADC value of 2.5 ×10−3 mm2/s using a b value of 400 s/mm2 or greater.

Conclusion

DW‐EPIs with middle b values were not required in the detection and characterization of benign and malignant hepatic lesions. J. Magn. Reson. Imaging 2008;28:691–697. © 2008 Wiley‐Liss, Inc.
Diffusion tensor imaging and fiber tractography of C6 rat glioma
Authors: Asanuma Taketoshi , Doblas Sabrina , Tesiram Yasvir A. , Saunders Debra , Cranford Rebecca , Pearson Jamie , Abbott Andrew , Smith Nataliya , Towner Rheal A.
Published: September 2008

Purpose

To apply diffusion tensor images using 30 noncollinear directions for diffusion‐weighted gradient schemes to characterize diffusion tensor imaging (DTI) features associated with C6 glioma‐bearing rat brains, and ideally visualize fiber tractography datasets.

Materials and Methods

Fiber tractographies of normal male Fischer 344 rat brains were constructed from DTI datasets acquired with a 30 noncollinear diffusion gradient scheme. Cultured C6 cell were intracranially injected into the cortex of male Fischer 344 rats. The time course of the tumor growth was monitored with DTI and fiber tractography using diffusion‐weighting gradients in 30 noncollinear directions.

Results

Fiber tractographies through the corpus callosum (CC) were easily visualized with the 30‐direction gradient scheme, and the fiber trajectories of the motor cortex and striatum were well represented in normal rats. Fiber tractography indicated that the neuronal fibers of the CC were compressed or disappeared by growing C6 glioma, which affected surrounding brain tissue.

Conclusion

We have demonstrated in this study that fiber tractography with the 30 noncollinear diffusion gradient scheme method can be used to help provide a better understanding regarding the influence of a tumor on the surrounding regions of normal brain tissue in vivo. J. Magn. Reson. Imaging 2008;28:566–573. © 2008 Wiley‐Liss, Inc.
A dual‐projection respiratory self‐gating technique for whole‐heart coronary MRA
Authors: Lai Peng , Larson Andrew C. , Bi Xiaoming , Jerecic Renate , Li Debiao
Published: September 2008

Purpose

To investigate the accuracy of a dual‐projection respiratory self‐gating (DP‐RSG) technique in dynamic heart position measurement and its feasibility for free‐breathing whole‐heart coronary MR angiography (MRA).

Materials and Methods

A DP‐RSG method is proposed to enable accurate direct measurement of heart position by acquiring two whole‐heart projections. On 14 volunteers we quantitatively evaluated the efficacy of DP‐RSG by comparison with diaphragmatic navigator (NAV) and single‐projection‐based respiratory self‐gating (SP‐RSG) methods. For DP‐RSG we also compared center‐of‐mass and two profile‐matching algorithms in deriving heart motion. Coronary imaging was conducted on eight volunteers based on retrospective gating to preliminarily validate the effectiveness of DP‐RSG for whole‐heart coronary MRA. Comparison of vessel delineation was performed between images reconstructed using different gating methods.

Results

The quantitative evaluation shows that DP‐RSG more accurately tracks heart motion than NAV with all gating window (GW) values and SP‐RSG approaches with GW ≥2.5 mm and profile‐matching algorithms are more reliable for motion derivation than center‐of‐mass calculations with GW ≥1.0 mm. Whole‐heart coronary MRA studies demonstrate the feasibility of using DP‐RSG to improve overall delineation of the coronary arteries.

Conclusion

DP‐RSG is a promising approach to better resolve respiratory motion for whole‐heart coronary MRA compared to conventional NAV and SP‐RSG. J. Magn. Reson. Imaging 2008;28:612–620. © 2008 Wiley‐Liss, Inc.
Dynamic changes in murine vessel geometry assessed by high‐resolution magnetic resonance angiography: A 9.4T study
Authors: Jacoby Christoph , Böring Yang Chul , Beck Andreas , Zernecke Alma , Aurich Volker , Weber Christian , Schrader Jürgen , Flögel Ulrich
Published: September 2008

Purpose

To establish high‐resolution magnetic resonance angiography (MRA) protocols to monitor and quantify dynamic changes of vascular remodeling in pathologic mouse models.

Materials and Methods

Time‐of‐flight (TOF) MRA of murine vessels was performed at 9.4T to monitor temporal alterations in the vessel structure in two frequently used injury models (wire denudation of carotid artery and femoral artery occlusion). Quantification of vessel morphology was performed with the use of in‐house‐developed software and validated by estimation of inter‐ and intraobserver variabilities and reproducibility, and by correlation with histological data.

Results

MRA‐based volume determination exhibited low intra‐ and interobserver variabilities and high reproducibility. Furthermore, good correlations with histological data were found four weeks after injury (R2 = 0.970). Two high‐resolution image series are presented to demonstrate the applicability of the technique: 1) the time course of a vessel stenosis that reopens by thrombus recanalization, and 2) the continuous restoration of blood flow by collateral vessel formation during arteriogenesis after induction of hindlimb ischemia.

Conclusion

We describe high‐resolution MRA imaging protocols that are suitable for sensitively measuring the extent and time course of changes in vessel morphology in mice in a repetitive manner without any contrast agent. This methodology provides a reliable tool for noninvasive monitoring of vascular lesion development or neovascularization in transgenic mice. J. Magn. Reson. Imaging 2008;28:637–645. © 2008 Wiley‐Liss, Inc.
High‐spatial‐resolution three‐dimensional MR cholangiography using a high‐sampling‐efficiency technique (SPACE) at 3T: Comparison with the conventional constant flip angle sequence in healthy volunteers
Authors: Arizono Shigeki , Isoda Hiroyoshi , Maetani Yoji S. , Hirokawa Yuusuke , Shimada Kotaro , Nakamoto Yuji , Togashi Kaori
Published: September 2008

Purpose

To evaluate the image quality of high‐spatial‐resolution three‐dimensional magnetic resonance cholangiography (MRC) with a high‐sampling‐efficiency technique (sampling perfection with application optimized contrasts using different flip angle evolutions [SPACE]) in comparison with a conventional constant flip angle (FA) sequence at 3T.

Materials and Methods

Eighteen volunteers were examined on a 3T MR unit using MRC imaging performed with three different free‐breathing three‐dimensional T2‐weighted turbo spin‐echo (TSE) sequences: 1) SPACE (spatial resolution, 1.1 × 1.0 × 0.84 mm), 2) constant FA (1.1 × 1.0 × 0.84 mm), and 3) SPACE at a higher resolution (SPACE HR; 1.0 × 0.9 × 0.644 mm). A five‐point scale was used to compare overall image quality and visualization of the third branches of the bile duct (B2, B6, and B8). Depictions of cystic duct insertion and the highest order of bile duct visible were also compared.

Results

MRC with SPACE and SPACE HR sequences produced significantly better overall image quality than the constant FA sequence. In all analyses of duct visibility, SPACE and SPACE HR sequences showed higher scores than the constant FA sequence.

Conclusion

High‐resolution three‐dimensional MRC with SPACE at 3T allows high‐quality imaging of the biliary tract, and has the ability to depict nondilated intrahepatic bile ducts (IHBD) in healthy volunteers. J. Magn. Reson. Imaging 2008;28:685–690. © 2008 Wiley‐Liss, Inc.
Navigator‐triggered prospective acquisition correction (PACE) technique vs. conventional respiratory‐triggered technique for free‐breathing 3D MRCP: An initial prospective comparative study using healthy volunteers
Authors: Morita Satoru , Ueno Eiko , Suzuki Kazufumi , Machida Haruhiko , Fujimura Mikihiko , Kojima Shinya , Hirata Masami , Ohnishi Takahiro , Imura Chiaki
Published: September 2008

Purpose

To confirm the superiority of the navigator‐triggered prospective acquisition correction (PACE) technique over the conventional respiratory‐triggered (RESP) technique, something that has been perceived experimentally but without definite evidence, for free‐breathing three‐dimensional (3D) magnetic resonance cholangiopancreatography (MRCP) using healthy volunteers.

Materials and Methods

Free‐breathing 3D turbo spin‐echo MRCP using both PACE and RESP techniques were prospectively performed on 25 healthy volunteers. Quantitative analyses of acquisition time, signal‐to‐noise ratio, contrast‐to‐noise ratio, and contour sharpness index of each segment of the pancreaticobiliary tree were compared using the paired t‐test. Qualitative analyses on a five‐point scale (1, excellent; 5, poor) scored by two independent radiologists were compared using the Wilcoxon signed‐rank test.

Results

The subjective image quality and contour sharpness index of each segment of the PACE technique were found to be significantly better than those for RESP (P < 0.05). No significant difference was observed with regard to signal‐to‐noise and contrast‐to‐noise ratios except for the pancreatic duct. No significant difference in acquisition times between PACE and RESP techniques was observed.

Conclusion

We confirmed the superiority of the image quality of the PACE technique compared to conventional RESP technique for free‐breathing 3D MRCP in healthy volunteers. J. Magn. Reson. Imaging 2008;28:673–677. © 2008 Wiley‐Liss, Inc.
Evaluation of locally recurrent pelvic malignancy: Performance of T2‐ and diffusion‐weighted MRI with image fusion
Authors: Nishie Akihiro , Stolpen Alan H. , Obuchi Masao , Kuehn David M. , Dagit Aaron , Andresen Kelli
Published: September 2008

Purpose

To evaluate the performance of T2‐ and diffusion‐weighted magnetic resonance imaging (MRI) with image fusion for detection of locally recurrent pelvic malignancy.

Materials and Methods

The study group consisted of 28 patients (27 female, 1 male) who underwent pelvic MRI at 1.5 T after treatment of pelvic malignancy. MR images were reviewed independently by three blinded readers. The performance of the four sequences for detecting local recurrence was evaluated using receiver operating characteristic analysis: T2‐weighted fast spin‐echo (FSE), diffusion‐weighted echo‐planar imaging (DWI), dynamic contrast‐enhanced (DCE) fat‐suppressed T1‐weighted spoiled gradient echo (SPGR), and T2‐DWI with image fusion, the latter created using OsiriX Medical Imaging Software.

Results

Local recurrence was confirmed at biopsy in 16 patients. Twelve patients showed no evidence of recurrence on two consecutive MRI studies. The Az value for T2‐DWI with image fusion (0.949) was statistically greater than that for T2‐weighted FSE (0.849) (P < 0.05). The sensitivity and specificity was 87.5% and 47.2%, respectively, for T2‐weighted FSE, 100.0% and 50.0% for DWI, 95.8% and 58.3% for DCE fat‐suppressed T1‐weighted SPGR, and 93.8% and 72.2% for T2‐DWI with image fusion.

Conclusion

For depicting locally recurrent pelvic malignancy, T2‐DWI with image fusion outperforms standard T2‐weighted FSE and DWI and is comparable to DCE fat‐suppressed T1‐weighted SPGR. J. Magn. Reson. Imaging 2008;28:705–713. © 2008 Wiley‐Liss, Inc.
Investigation and optimization of parameter accuracy in dynamic contrast‐enhanced MRI
Authors: Cheng Hai‐Ling Margaret
Published: September 2008

Purpose

To present a modified pharmacokinetic model for improved parameter accuracy and to investigate the influence of an inaccurate arterial input function (AIF) on dynamic contrast‐enhanced (DCE)‐MRI parameter estimates of the transfer constant (Ktrans), blood volume (vp), and interstitial volume (ve).

Materials and Methods

Tissue uptake curves were simulated over a large range of physiological values and analyzed for different AIF measurement errors and temporal resolutions. The AIF measurement was assumed to be inaccurate in the bolus amplitude (rapid sampling) or susceptible to unknown temporal offsets (slow sampling with biexponential decay fit).

Results

The modified model adequately reduces errors in parameter estimates arising from transit time effects. An error in the AIF bolus amplitude results in an inversely proportional error in Ktrans and vp; ve remains robust. More consistent error in Ktrans (≈20% underestimation) was obtained using a biexponential AIF, at the expense of severely underestimating vp.

Conclusion

While an accurate, high temporal resolution AIF is essential for estimating vp, a biexponential AIF acquired at low temporal resolution (<20 seconds) provides robust estimates of ve and results in a Ktrans underestimation comparable to that from a 25% error in the initial AIF bolus amplitude. J. Magn. Reson. Imaging 2008;28:736–743. © 2008 Wiley‐Liss, Inc.
Dynamic contrast‐enhanced (DCE) derived transfer coefficient (ktrans) is a surrogate marker of matrix metalloproteinase 9 (MMP‐9) expression in brain tuberculomas
Authors: Haris Mohammad , Husain Nuzhat , Singh Anup , Awasthi Rishi , Singh Rathore Ram Kishore , Husain Mazhar , Gupta Rakesh K.
Published: September 2008

Purpose

To correlate dynamic contrast‐enhanced (DCE) MRI derived perfusion indices with immunohistochemically obtained vascular endothelial growth factor (VEGF) and matrix metalloproteinase‐9 (MMP‐9) in a cellular fraction of brain tuberculomas (BT).

Materials and Methods

Thirteen BT patients underwent DCE MRI. Perfusion indices (cerebral blood volume [CBV], transfer coefficient [ktrans] and leakage [ve]) maps were generated for the quantitative analysis. The CBV was corrected for the leaky blood–brain barrier (BBB). The relative CBV (rCBV), ktrans, and ve were calculated by placing 10 regions of interest (ROIs) showing the highest values in the lesion. The percentage area of VEGF and percentage area of MMP‐9 and microvessel density (MVD) were quantified from 10 fields per lesion with maximal expression of the excised BT. Pearson correlation analysis between physiological indices and quantitative VEGF, MMP‐9, and MVD was performed for each ROI.

Results

The average value of rCBV, ktrans, ve, VEGF, MMP‐9, and MVD were 3.53 ± 0.37, 2.04 ± 0.40 min−1, 0.71 ± 0.09, 12.51 ± 2.56, 18.09 ± 2.06, 10.87 ± 1.99, respectively. The ktrans (r = 0.918, P < 0.001) and ve (r = 0.899, P < 0.001) showed significant correlation with MMP‐9, while rCBV correlated significantly with MVD (r = 0.962, P < 0.001) and VEGF (r = 0.868, P < 0.001).

Conclusion

We conclude that the expression of MMP‐9, a marker of BBB disruption and disease activity in BT correlates with DCE‐derived ktrans and thus has the potential to be used as its surrogate marker. J. Magn. Reson. Imaging 2008;28:588–597. © 2008 Wiley‐Liss, Inc.
Agreement between different input image types in brain atrophy measurement in multiple sclerosis using SIENAX and SIENA
Authors: Neacsu Veronica , Jasperse Bas , Korteweg Tijmen , Knol Dirk L. , Valsasina Paola , Filippi Massimo , Barkhof Frederik , Rovaris Marco , Vrenken Hugo
Published: September 2008

Purpose

To investigate whether multiple sclerosis (MS) atrophy can be assessed by SIENA and SIENAX software using other image types from MS research protocols than T1‐weighted images without contrast agent, which are not always available.

Materials and Methods

We selected 46 MS patients with identical magnetic resonance imaging (MRI) protocols at two timepoints. We calculated normalized brain volume (NBV) using SIENAX, and percentage brain volume change (PBVC) using SIENA, from T1‐weighted images with and without contrast agent, T2‐weighted images, and (calculated) pseudo‐T1‐weighted images. Relative agreement of the results was assessed using variance component estimation.

Results

Relative agreement with T1‐weighted images without contrast agent was good for T1‐weighted images with contrast agent (ICC = 0.86 for NBV, ICC = 0.77 for PBVC), and reasonably good for pseudo‐T1 and T2‐weighted images (T2: ICC = 0.72 for NBV, 0.58 for PBVC; pseudo‐T1: ICC = 0.68 for NBV, 0.83 for PBVC).

Conclusion

Brain atrophy can be studied using SIENA and SIENAX if T1‐weighted images without contrast agent are not available. T1‐weighted images with contrast agent should be used if available. Otherwise, pseudo‐T1 and T2‐weighted images seem acceptable and accessible alternatives. The use of these other images will greatly improve research possibilities, especially regarding older datasets. J. Magn. Reson. Imaging 2008;28:559–565. © 2008 Wiley‐Liss, Inc.
Apparent diffusion coefficient values in peripheral and transition zones of the prostate: Comparison between normal and malignant prostatic tissues and correlation with histologic grade
Authors: Tamada Tsutomu , Sone Teruki , Jo Yoshimasa , Toshimitsu Shinya , Yamashita Takenori , Yamamoto Akira , Tanimoto Daigo , Ito Katsuyoshi
Published: September 2008

Purpose

To investigate the utility of apparent diffusion coefficient (ADC) values for discriminating tumor in patients with prostate cancer from normal prostatic tissues in healthy adult men, and to identify correlations between ADC and histologic grade of prostate cancer.

Materials and Methods

A total of 125 healthy male volunteers (mean age, 60 years; range, 50–86 years) and 90 prostate cancer patients (mean age, 71 years; range, 51–88 years) underwent diffusion‐weighted imaging (DWI) of the prostate with a single‐shot echo‐planar imaging sequence using b‐factors of 0 and 800 sec/mm2. ADC was measured from two locations in the peripheral zone (PZ) and two locations in the central gland (CG) in normal subjects, and tumor locations of PZ or transition zone (TZ) in patients with prostate cancer.

Results

Mean ADC values of tumor regions in both PZ (1.02 ± 0.25 × 10−3 mm2/sec) and TZ (0.94 ± 0.21 × 10−3 mm2/sec) were significantly lower than those in the corresponding normal regions (1.80 ± 0.27 × 10−3 mm2/sec and 1.34 ± 0.14 × 10−3 mm2/sec, respectively) (P < 0.0001 each). Furthermore, a significant negative correlation was identified between ADC in PZ cancer and tumor Gleason score (ρ = −0.497, P < 0.0001).

Conclusion

ADC values appear to provide acceptable diagnostic accuracy in both PZ and TZ. J. Magn. Reson. Imaging 2008;28:720–726. © 2008 Wiley‐Liss, Inc.
Evaluation of cardiac biventricular segmentation from multiaxis MRI data: A multicenter study
Authors: Lötjönen Jyrki M.P. , Järvinen Vesa M. , Cheong Benjamin , Wu Edwin , Kivistö Sari , Koikkalainen Juha R. , Mattila Jussi J.O. , Kervinen Helena M. , Muthupillai Raja , Sheehan Florence H. , Lauerma Kirsi
Published: September 2008

Purpose

To validate a volumetric biventricular segmentation solution for multiaxis cardiac magnetic resonance (CMR) images.

Materials and Methods

The study population comprised 40 subjects. Biventricular end‐diastolic and ‐systolic phases were segmented from both short‐axis and horizontal long‐axis or transaxial cine CMR images. Segmentation was based on fitting nonrigidly a 3D surface model to multiaxis CMR images. Five segmentations were performed: two manual segmentations by experts, automatic segmentation, and two segmentations where a user was allowed to correct errors in the automatic segmentation for 2 minutes and without time limits. Volumetry, distance measures, and visual grading were used to evaluate the quality of the segmentation.

Results

No difference was observed between automatic and manual segmentations in volumetric measures of the ventricles. The manual segmentation performed better for left‐ventricular myocardial volume. The distance between surfaces as well as visual analysis did not show differences between automatic and manual segmentation for the endocardial border of the left ventricle but some corrections are needed for the right ventricle.

Conclusion

Fully automatic segmentation produces good results in the assessment of left ventricular volume andendocardial border. Two minutes of user interaction are needed to obtain accurate results for the right ventricle. J. Magn. Reson. Imaging 2008;28:626–636. © 2008 Wiley‐Liss, Inc.