bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic polymorphism of N‐acetyltransferase 2 in the susceptibility to laryngeal squamous cell carcinoma
Authors: Ünal Murat , Tamer Lülüfer , Akbaş Yücel , Pata Yavuz Selim , Vayisoǧlu Yusuf , Deǧirmenci Ulaş , Çamdeviren Handan
Published: September 2005

Background.

The purpose of this study was to investigate whether polymorphism of N‐acetyltransferase 2 (NAT2) genotypes are associated with the risk of laryngeal squamous cell carcinoma (SCC).

Methods.

The study group consisted of 45 white patients with laryngeal SCC (42 men, with a mean age of 54 years [range, 37–70 years] and three women, with a mean age of 47 years [range, 32–55 years]) and 104 control subjects (68 men and 36 women; mean age, 50 years; range, 28–73 years). All of the patients were primarily treated with surgical intervention. Blood samples (5 mL) were obtained before surgery or from the patients under follow‐up to 5 years after surgery (mean follow‐up, 27 months; range, 6–48 months). DNA was extracted from the lymphocytes by high pure template preparation kit. NAT2*5A, NAT2*6A, NAT2*7A/B, and NAT2*14A were detected by use of LightCycler‐NAT2 mutation detection kit by real‐time polymerase chain reaction with Light Cycler instruments. The association between NAT2 polymorphisms and laryngeal SCC was prospectively modeled through multivariate logistic regression analysis.

Results.

We found that the risk of laryngeal SCC was 7.3‐fold higher in individuals with NAT2*5 mutant allele, 3.8‐fold higher in subjects with NAT2*6 heterozygote allele, and 38.3‐fold higher in NAT2*6 mutant allele. We also found that individuals with NAT2*7 heterozygote allele had a 0.2‐fold less risk for the development of laryngeal SCC (p = .018).

Conclusion.

In this population, patients with NAT2*5 mutant and *6 heterozygous and mutant genotypes had a significantly higher risk for development of laryngeal SCC. © 2005 Wiley Periodicals, Inc. Head Neck 27: XXX–XXX, 2005
Pattern of nonspecific (or global) DNA methylation in oral carcinogenesis
Authors: Piyathilake Chandrika J. , Bell Walter C. , Jones Jennifer , Henao Olga L. , Heimburger Douglas C. , Niveleau Alain , Grizzle William E.
Published: September 2005

Background.

Although alterations in nonspecific (or global) DNA methylation (GDM) in specific cells are known to be involved in the process of lung carcinogenesis, similar associations have not been evaluated in other smoking‐related cancers of the head and neck.

Methods.

We evaluated the status of GDM by using monoclonal antibodies specific for 5‐methylcytosine (5‐mc) in oral squamous cell carcinoma (SCC) specimens of 48 cigarette smokers who had SCC develop and in 93 age‐, race‐, and sex‐matched smokers who did not.

Results.

Percentages of cells positive for 5‐mc immunostaining of DNA of SCC and dysplastic lesions were significantly higher than those of normal oral epithelial cells from cancer subjects and from noncancer subjects. The degree of DNA methylation was unrelated to DNA content.

Conclusions.

The pattern of GDM in oral SCCs is different from that of lung SCCs. The differences in nutrient risk factor profiles that are related to GDM and differential activity of DNA methyltranferases between oral and lung SCCs may explain these observations. © 2005 Wiley Periodicals, Inc. Head Neck 27: XXX–XXX, 2005
Overexpression of regucalcin suppresses apoptotic cell death in cloned normal rat kidney proximal tubular epithelial NRK52E cells: Change in apoptosis‐related gene expression
Authors: Nakagawa Taeko , Yamaguchi Masayoshi
Published: September 2005

The effect of regucalcin, a regulatory protein in intracellular signaling pathway, on cell death and apoptosis was investigated using the cloned normal rat kidney proximal tubular epithelial NRK52E cells overexpressing regucalcin. NRK52E cells (wild type) and stable regucalcin (RC)/pCXN2 transfectants were cultured for 72 h in a medium containing 5% bovine serum (BS) to obtain subconfluent monolayers. After culture for 72 h, cells were further cultured for 24–72 h in a medium without BS containing either vehicle, tumor necrosis factor‐α (TNF‐α; 0.1 or 1.0 ng/ml of medium), lipopolysaccharide (LPS; 0.1 or 1.0 µg/ml), Bay K 8644 (10−9–10−7 M), or thapsigargin (10−9–10−7 M). The number of wild‐type cells was significantly decreased by culture for 42–72 h in the presence of TNF‐α (0.1 or 1.0 ng/ml), LPS (0.1 or 1.0 µg/ml), Bay K 8644 (10−7–10−5 M), or thapsigargin (10−8 or 10−7 M). The effect of TNF‐α (0.1 or 1.0 ng/ml), LPS (0.1 or 1.0 µg/ml), Bay K 8644 (10−7–10−6 M), or thapsigargin (10−7 M) in decreasing the number of wild‐type cells cultured for 24–72 h was significantly prevented in transfectants overexpressing regucalcin. Agarose gel electrophoresis showed the presence of low‐molecular‐weight deoxyribonucleic acid (DNA) fragments of adherent wild‐type cells cultured with LPS (1.0 µg/ml), Bay K 8644 (10−7 M), or thapsigargin (10−8 M) for 24 h, and this DNA fragmentation was significantly suppressed in transfectants. DNA fragmentation in adherent cells was not seen by culture with TNF‐α (1.0 ng/ml). TNF‐α‐induced decrease in the number of wild‐type cells was significantly prevented by culture with caspase‐3 inhibitor (10−8 M), while LPS‐ or Bay K 8644‐induced decrease in cell number was significantly prevented by caspase‐3 inhibitor or N ω‐nitro‐L‐arginine methylester (NAME) (10−5 M), an inhibitor of nitric oxide (NO) synthase. Thapsigargin‐induced decrease in cell number was not prevented in the presence of two inhibitors. Bcl‐2 and Akt‐1 mRNA levels were significantly increased in transfectants cultured for 24 h as compared with those of wild‐type cells, while Apaf‐1, caspase‐3, or glyceroaldehyde‐3‐phosphate dehydrogenase (G3PDH) mRNA expressions were not significantly changed in transfectants. Culture with TNF‐α (1.0 ng/ml), LPS (1.0 µg/ml), Bay K 8644 (l0−7 M), or thapsigargin (10−8 M) caused a significant increase in caspase‐3 mRNA levels in wild‐type cells. LPS (1.0 µg/ml) significantly decreased Bcl‐2 mRNA expression in the cells. Their effects on the gene expression of apoptosis‐related proteins were not significantly changed in transfectants. This study demonstrates that overexpression of regucalcin has a suppressive effect on cell death and apoptosis induced by various factors which their action are mediated through many intracellular signaling pathways, and that it modulates the gene expression of apoptosis‐related proteins. J. Cell. Biochem. © 2005 Wiley‐Liss, Inc.
Calcium oscillations and mammalian egg activation
Authors: Malcuit Christopher , Kurokawa Manabu , Fissore Rafael A.
Published: September 2005

Fertilization in all species studied to date induces an increase in the intracellular concentration of free calcium ions ([Ca2+]i) within the egg. In mammals, this [Ca2+]i signal is delivered in the form of long‐lasting [Ca2+]i oscillations that begin shortly after fusion of the gametes and persist beyond the time of completion of meiosis. While not fully elucidated, recent evidence supports the notion that the sperm delivers into the ooplasm a trigger of oscillations, the so‐called sperm factor (SF). The recent discovery that mammalian sperm harbor a specific phospholipase C (PLC), PLCζ has consolidated this view. The fertilizing sperm, and presumably PLCζ promote Ca2+ release in eggs via the production of inositol 1,4,5‐trisphosphate (IP3), which binds and gates its receptor, the type‐1 IP3 receptor, located on the endoplasmic reticulum, the Ca2+ store of the cell. Repetitive Ca2+ release in this manner results in a positive cumulative effect on downstream signaling molecules that are responsible for the completion of all the events comprising egg activation. This review will discuss recent advances in our understanding of how [Ca2+]i oscillations are initiated and regulated in mammals, highlight areas of discrepancies, and emphasize the need to better characterize the downstream molecular cascades that are dependent on [Ca2+]i oscillations and that may impact embryo development. © 2005 Wiley‐Liss, Inc.
Interaction and functional cooperation between the serine/threonine kinase bone morphogenetic protein type II receptor with the tyrosine kinase stem cell factor receptor
Authors: Hassel Sylke , Yakymovych Mariya , Hellman Ulf , Rönnstrand Lars , Knaus Petra , Souchelnytskyi Serhiy
Published: September 2005

Transmembrane receptors with intrinsic serine/threonine or tyrosine kinase domains regulate vital functions of cells in multicellular eukaryotes, e.g., differentiation, apoptosis, and proliferation. Here, we show that bone morphogenetic protein type II receptor (BMPR‐II) which has a serine/threonine kinase domain, and stem cell factor receptor (c‐kit) which contains a tyrosine kinase domain form a complex in vitro and in vivo; the interaction is induced upon treatment of cells with BMP2 and SCF. Stem cell factor (SCF) modulated BMP2‐dependent activation of Smad1/5/8 and phosphorylation of Erk kinase. SCF also enhanced BMP2‐dependent differentiation of C2C12 cells. We found that BMPR‐II was phosphorylated at Ser757 upon co‐expression with and activation of c‐kit. BMPR‐II phosphorylation required intact kinase activity of BMPR‐II. Abrogation of the c‐kit/SCF‐dependent phosphorylation of BMPR‐II at the Ser757 interfered with the cooperative effect of BMP2 and SCF. Our data suggest that the complex formation between c‐kit and BMPR‐II leads to phosphorylation of BMPR‐II at Ser757, which modulates BMPR‐II‐dependent signaling. J. Cell. Physiol. 206: 457–467, 2006. © 2005 Wiley‐Liss, Inc.
Enhancement of apoptosis by nitric oxide released from α‐phenyl‐tert‐butyl nitrone under hyperthermic conditions
Authors: Cui Zheng‐Guo , Kondo Takashi , Matsumoto Hideki
Published: September 2005

The aim of this study was to examine whether a neuroprotector, PBN (α‐phenyl‐tert‐butyl nitrone), enhances apoptosis induced by hyperthermia, which generates superoxide (O) intracellularly, since the release of nitric oxide (NO) from PBN under oxidative stress has been reported. When human myelomonocytic lymphoma U937 cells were treated with hyperthermia (44°C, 10 min) and PBN, an increase in the concentration of nitrite in the culture medium, and a decrease in the hyperthermia‐induced production of O was observed. Imaging using a fluorescence dye for intracellular NO, diaminofluorescein‐2 diacetate (DAF‐2 DA), revealed the formation of NO in the apoptotic cells treated with hyperthermia and PBN combined. Apoptotic endpoints were significantly enhanced by the combined treatment: a decrease in mitochondrial trans‐membrane potential, cleavage of Bid, release of cytochrome c, and activation of caspase‐8 and ‐3. An increase in the intracellular Ca2+ concentration ([Ca2+]i), externalization of Fas, and decrease in Hsp70 and phosphorylated HSF1 were observed following the combined treatment. Furthermore, scavengers of NO and ONOO− significantly inhibited the enhancement of apoptosis, the externalization of Fas and the increase in [Ca2+]i. These results suggest that, (1) NO is released from PBN by hyperthermia, and subsequently reacts with O to form ONOO−, (2) NO and ONOO− are involved in the enhancement of apoptosis through Fas‐mitochondria‐caspase and [Ca2+]i‐dependent pathways, and (3) a decrease in Hsp70 and phosphorylated HSF1 also contributed to the enhancement of apoptosis. J. Cell. Physiol. 206: 468–476, 2006. © 2005 Wiley‐Liss, Inc.
Ligand concentration is a driver of divergent signaling and pleiotropic cellular responses to FGF
Authors: Garcia‐Maya Mitla , Anderson Alexandra A. , Kendal Claire E. , Kenny Anna V. , Edwards‐Ingram Laura C. , Holladay Andrew , Saffell Jane L.
Published: September 2005

Fibroblast growth factors (FGFs) are soluble ligands important for embryonic patterning, limb and brain development, and stem cell proliferation. They activate specific receptors (FGFR) to elicit changes in gene expression and cellular responses such as proliferation, differentiation, and survival, but the extent to which these pleiotropic responses are driven by FGF concentration gradients has not been systematically addressed. Here, we show that a single cell type exhibits divergent, even opposing, responses to a single FGF dependent on the exposure concentration, and that this is controlled by differential signaling with specific negative feedback inhibition. Low concentrations of FGF2 stimulate survival and differentiation but actively inhibit proliferation while intermediate concentrations stimulate proliferation in the presence of serum but apoptosis in its absence. Intriguingly, high concentrations reverse the proliferation and apoptosis effects, and mirror the low concentration effects: inhibition of proliferation and stimulation of survival and differentiation. By screening for activation of sampled signaling intermediates across the FGF2 concentration range in fibroblasts, we show that the peak in proliferation and apoptosis correlates with abrupt activation of FRS‐2 and Erk that is specifically down‐regulated by high concentrations of FGF2, a pattern that contrasts with an incremental increase in activation of p38 MAP kinase and the FGFR itself, across the FGF2 concentration range. Whilst proliferation stimulated by FGF2 was dependent on p38 MAP kinase, apoptosis stimulated by proliferative concentrations of FGF2 under serum‐free conditions was, in contrast, dependent on Erk MAP kinase. These findings indicate that FGF exposure concentration precisely controls intracellular signaling and cellular responses to the growth factor, and have important implications for understanding how FGF gradients influence cell proliferation, survival, and differentiation during processes such as limb development. J. Cell. Physiol. 206: 386–393, 2006. © 2005 Wiley‐Liss, Inc.
Urokinase (u‐PA) is produced by collecting duct principal cells and is post‐transcriptionally regulated by SV40 large‐T, arginine vasopressin, and epidermal growth factor
Authors: Piedagnel Rémi , Tiger Yoann , Lelongt Brigitte , Ronco Pierre M.
Published: September 2005

We have analyzed the expression and regulation of plasminogen activators (PA) in principal cells of the renal collecting duct. We used a rabbit principal cell line (RC.SVtsA58) infected with the temperature‐sensitive SV40 strain tsA58. Transformed cells cultured at permissive temperature (33°C) produced only tissue‐type plasminogen activator (t‐PA). Shifting the cells to nonpermissive temperature (39.5°C) induced their differentiation and a marked increase in total fibrinolytic activity due to the induction of urokinase‐type plasminogen activator (u‐PA) synthesis and secretion. The effect on u‐PA was post‐transcriptional and it could be attributed to large‐T inactivation at 39.5°C since it was abolished by re‐infecting the cells with wild‐type SV40. Run‐on assay and real‐time RT‐PCR of u‐PA transcripts indicated that large‐T altered post‐transcriptional regulation. u‐PA was also produced by primary cultures of collecting duct cells and was present in the rabbit urine. In the kidney, u‐PA and its receptor (u‐PAR) were almost exclusively expressed at the apex of collecting duct cells. We then analyzed the regulation of u‐PA by arginine vasopressin (AVP) and epidermal growth factor (EGF), two key regulators of principal cell functions. We found that AVP and EGF, which have opposite hydro‐osmotic effects in the collecting duct, also exhibited contrasted effects on u‐PA synthesis in differentiated RC.SVtsA58 cells. EGF increased but AVP suppressed u‐PA activity and protein, and these regulations occurred at post‐transcriptional level. These results point to a physiological role of u‐PA in principal cells of the renal collecting duct. J. Cell. Physiol. 206: 394–401, 2006. © 2005 Wiley‐Liss, Inc.
Increased transcriptional response to mechanical strain in keloid fibroblasts due to increased focal adhesion complex formation
Authors: Wang Zhen , Fong Kenton D. , Phan Toan‐Thang , Lim Ivor J. , Longaker Michael T. , Yang George P.
Published: September 2005

Clinicians have observed that keloids preferentially form in body areas subject to increased skin tension. We hypothesized a difference exists in the transcriptional response of keloid fibroblasts to mechanical strain compared with normal fibroblasts. Normal and keloid fibroblasts were seeded in a device calibrated to deliver a known level of equibiaxial strain. We examined the transcriptional response of TGF‐β isoforms and collagen Iα, genes differentially expressed in keloids. Keloid fibroblasts produced more mRNA for TGF‐β1, TGF‐β2, and collagen Iα after mechanical strain compared to normals, and this was correlated with protein production. Inhibiting the major mechanical signal transduction pathway with the ERK inhibitor, U0126, blocked upregulation of gene expression. In addition, keloid fibroblasts formed more focal adhesion complexes as measured by immunofluorescence for focal adhesion kinase, integrin β1, and vinculin. Finally, there is increased activation of focal adhesion kinase when we detected the phosphorylated form of focal adhesion kinase with immunofluorescence and immunoblotting. In summary, keloid fibroblasts have an exaggerated response to mechanical strain compared to normal fibroblasts leading to increased production of pro‐fibrotic growth factors. This may be one molecular mechanism for the development of keloids. J. Cell. Physiol. 206: 510–517, 2006. © 2005 Wiley‐Liss, Inc.
The epigenetic network regulating muscle development and regeneration
Authors: Palacios Daniela , Puri Pier Lorenzo
Published: September 2005

This review focuses on our current knowledge of the epigenetic changes regulating gene expression at the chromatin and DNA level, independently on the primary DNA sequence, to reprogram the nuclei of muscle precursors during developmental myogenesis and muscle regeneration. These epigenetic marks provide the blueprint by which the extra‐cellular cues are interpreted at the nuclear level by the transcription machinery to select the repertoire of tissue‐specific genes to be expressed. The reversibility of some of these changes necessarily reflects the dynamic nature of skeletal myogenesis, which entails the progression through two antagonistic processes—proliferation and differentiation. Other epigenetic modifications are instead associated to events conventionally considered as irreversible—e.g. maintenance of lineage commitment and terminal differentiation. However, recent results support the possibility that these events can be reversed, at least upon certain experimental conditions, thereby revealing a dynamic nature of many of the epigenetic modifications underlying skeletal myogenesis. The elucidation of the epigenetic network that regulates transcription during developmental myogenesis and muscle regeneration might provide the information instrumental to devise pharmacological interventions toward selective manipulation of gene expression to promote regeneration of skeletal muscles and possibly other tissue. J. Cell. Physiol. 207: 1–11, 2006. © 2005 Wiley‐Liss, Inc.
Localization, specific activity, and molecular forms of acetylcholinesterase in developmental stages of the cestode Mesocestoides corti
Authors: Kemmerling U. , Cabrera G. , Campos E.O. , Inestrosa N.C. , Galanti N.
Published: September 2005

The nervous system of flatworms is quite simple although there is increasing evidence indicating that it is chemically complex. Studies of the nervous system in these animals have only been performed in the larval stage or in the adult worms, which are easy to obtain in nature, while the description of the nervous system in developing stages of these organisms is missing. Mesocestoides corti is a parasitic platyhelminth whose larvae can be induced in vitro to develop to adult, sexually mature worms, opening the possibility of studying the nervous system of a flatworm in different stages of development. Here, we describe the presence, activity, location, and molecular forms of acetylcholinesterase (AChE) in different stages of development of M. corti, from the larvae to adult forms of this endoparasite, obtained in in vitro cultures after induction of the larval stage with trypsin. Our results point to AChE as a molecular marker of the nervous system in platyhelminthes. The change in molecular forms of this enzyme and the increase in its activity during development from larvae to adult worm may reflect the presence of a more complex nervous system, necessary to adjust and coordinate the movement of a much bigger structure. A relationship between the development of the reproductive apparatus in segmented and adult worms with a more complex nervous system in these stages is also apparent. Finally, our study opens the possibility of applying anti‐AChE as more effective therapeutic strategies against cestode parasites. J. Cell. Physiol. 206: 503–509, 2006. © 2005 Wiley‐Liss, Inc.
Embryonic development of Galloisiana yuasai Asahina, with special reference to external morphology (Insecta: Grylloblattodea)
Authors: Uchifune Toshiki , Machida Ryuichiro
Published: September 2005

The embryogenesis of Grylloblattodea, one of the most primitive of the polyneopteran orders, is described using Galloisiana yuasai with special reference to external morphology. The egg membranes are characterized by an endochorion crossed by numerous vertical aeropyles and a fairly thin vitelline membrane, features shared by Mantophasmatodea. The inner layer formation is of the fault type. Serosal elements in the amnioserosal fold differentiate into hydropylar cells, to function in water absorption together with specialized amniotic structures, i.e., an amniotic strand and a thickened amnion. The germ band is of the short germ type. The germ band immerses deep into the yolk after its full elongation along the egg surface, and in this respect blastokinesis closely resembles that of Mantophasmatodea. The embryological features, i.e., those on egg membranes and blastokinesis, may suggest a closer affinity of Grylloblattodea and Mantophasmatodea. Appendages, ectodermal invaginations, and sternal and pleural sclerites are discussed in the light of serial homology, to provide a new basis for elucidating the insect body plan. Appendages are divided into the proximal coxopodite and distal telopodite, the former being divided further into the subcoxa and coxa. Subcoxal and coxal elements are identified in the mandible as well as in the abdominal appendages. The subcoxa is divided into the epimeron and episternum by the pleural suture in thoracic segments. Likewise, in the abdominal segments the subcoxa is divided into two, although the homologs of the epimeron and episternum are not sclerotized, and in the labial segment the subcoxal derivative or the postmentum is divided into the submentum and mentum. Two coxal endites bulge out from the medial side of the gnathal appendages. The mandibular molar and incisor, maxillary lacinia and galea, and labial glossa and paraglossa are serially homologous with each other. In the thoracic segments the original embryonic sternum or “protosternum” is largely replaced by subcoxal elements, and merely remains as a small anterior presternum and a posterior spinasternum. A major part of the venter is represented by the derivatives of the episternum such as an extensive basisternum, katepisternum, and trochantin and the medial element of the epimeron. The pleuron is derived from the episternal elements or the anepisternum and preepisternum, which bears a spiracle in the mesothorax and metathorax, and the lateral element of the epimeron. The homolog of the preepisternum in the prothorax is the cervical sclerite, but with no spiracle developed. A median ventral invagination arises in the thoracic segments as a spina, and the homolog of the spina develops into the eversible sac in the first abdominal segment. J. Morphol. © 2005 Wiley‐Liss, Inc.
Determination and analysis of guided wave propagation using magnetic resonance elastography
Authors: Romano A. J. , Abraham P. B. , Rossman P. J. , Bucaro J. A. , Ehman R. L.
Published: September 2005

We present a novel extension of standard magnetic resonance elastography (MRE) measurement and analysis methods, which is applicable in cases where the medium is characterized by waveguides or fiber bundles (i.e., muscle) leading to constrained propagation of elastic waves. As a demonstration of this new method, MRI is utilized to identify the pathways of the individual fibers of a stalk of celery, and 3D MRE is then performed throughout the volume containing the celery fibers for a measurement of the displacements. A Helmholtz decomposition is performed permitting a separation of the displacements into longitudinal and transverse components, and an application of a hybrid Radon transform permits a spectral decomposition of wave propagation along the fibers. Dot product projections between these elastic displacements measured in the global coordinate system and three Frenet vectors representing the tangent and two corresponding orthogonal vectors along any particular fiber orientation yield the displacement contributions to wave propagation along the fiber as if it were a waveguide. A sliding window spatial Fourier transform is then performed along the length of each fiber to obtain dispersion images that portray space–wavenumber profiles. Therefore, this method can permit localized tracking and characterization of wave types, velocities, and coupling along arbitrarily oriented fibers. Magn Reson Med, 2005. Published 2005 Wiley‐Liss, Inc.
Quantification of renal perfusion and function on a voxel‐by‐voxel basis: A feasibility study
Authors: Dujardin M. , Sourbron S. , Luypaert R. , Verbeelen D. , Stadnik T.
Published: September 2005

The feasibility of a voxel‐by‐voxel deconvolution analysis of T1‐weighted DCE data in the human kidney and its potential for obtaining quantification of perfusion and filtration was investigated. Measurements were performed on 14 normal humans and 1 transplant at 1.5 T using a Turboflash sequence. Signal time‐courses were converted to tracer concentrations and deconvolved with an aorta AIF. Parametric maps of relative renal blood flow (rRBF), relative renal volume of distribution (rRVD), relative mean transit time (rMTT), and whole cortex extraction fraction (E) were obtained from the impulse response functions. For the normals average cortical rRBF, rRVD, rMTT, and E were 1.6 mL/min/mL (SD 0.8), 0.4 mL/mL (SD 0.1), 17s (SD 7), and 22.6% (SD 6.1), respectively. A gradual voxelwise rRBF increase is found from the center of two infarction zones toward the edges. Voxel IRFs showed more detail on the nefron substructure than ROI IRFs. In conclusion, quantitative voxelwise perfusion mapping based on deconvolved T1‐DCE renal data is feasible, but absolute quantification requires inflow correction. rRBF maps and quantitative values are sufficiently sensitive to detect perfusion abnormality in pathologic areas, but further research is necessary to separate perfusion from extraction and to characterize the different compartments of the nephron on the (sub)voxel level. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Double average parallel steady‐state free precession imaging: Optimized eddy current and transient oscillation compensation
Authors: Markl M. , Leupold J. , Bieri O. , Scheffler K. , Hennig J.
Published: September 2005

Balanced steady‐state free precession (SSFP) imaging is sensitive to off‐resonance effects, which can lead to considerable artifacts during a transient phase following magnetization preparation or steady‐state interruption. In addition, nonlinear k‐space encoding is required if contrast‐relevant k‐space regions need to be acquired at specific delays following magnetization preparation or for transient artifact reduction in cardiac‐gated k‐space segmented CINE imaging. Such trajectories are problematic for balanced SSFP imaging due to nonconstant eddy current effects and resulting disruption of the steady state.

In this work, a novel acquisition strategy for balanced SSFP imaging is presented that utilizes scan time reduction by parallel imaging for optimized “double average” eddy current compensation and artifact reduction during the transient phase following steady‐state storage and magnetization preparation. Double average parallel SSFP imaging was applied to k‐space segmented CINE SSFP tagging as well as nongated centrically encoded SSFP imaging. Phantom and human studies exhibit substantial reduction in steady‐state storage and eddy current artifacts while maintaining spatial resolution, signal‐to‐noise ratio, and similar total scan time of a standard SSFP acquisition. The proposed technique can easily be extended to other acquisition schemes that would benefit from nonlinear reordering schemes and/or rely on interruption of the balanced SSFP steady state. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Intraluminal high intensity ultrasound treatment in the esophagus under fast MR temperature mapping: In vivo studies
Authors: Melodelima David , Salomir Rares , Chapelon Jean‐Yves , Theillère Yves , Moonen Chrit , Cathignol Dominique
Published: September 2005

New curative and palliative treatments are needed to respond to the poor prognosis of esophageal cancer. The purpose of this study was to determine whether magnetic resonance imaging (MRI) and MR thermometry can be used to monitor the thermal ablation induced by an intraluminal high‐intensity ultrasound applicator positioned in the esophagus. Experiments were performed in vivo in 2 pig esophagi (25 thermal lesions per pig). Respiratory gated or cardiac gated MR thermometry was performed with segmented echo‐planar imaging gradient echo sequences. All MR acquisitions were performed without susceptibility artifacts or radiofrequency interference with the ultrasound device. The experimental procedure proposed for accurate measurement of temperature in the esophagus was found to achieve an SD of ± 1.5°C for respiratory gating and ± 3.1°C for cardiac gating. Gd‐enhanced T1‐weighted images were used to depict coagulation necrosis. Autopsy was performed immediately after the treatment. Ultrasound effects were inspected visually, and the dimensions of the lesions in the liver neighboring the esophagus were compared with those determined on the MRI images. The visually assessed thermal lesions showed good correlation with the MRI data (10% mean volume difference). The feasibility of esophageal thermal ablation using intraluminal high‐intensity ultrasound and of on‐line MR temperature monitoring was demonstrated. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
New criteria for assessing fit quality in dynamic contrast‐enhanced T1‐weighted MRI for perfusion and permeability imaging
Authors: Balvay Daniel , Frouin Frédérique , Calmon Guillaume , Bessoud Bertrand , Kahn Edmond , Siauve Nathalie , Clément Olivier , Cuenod Charles A.
Published: September 2005

Contrast‐enhanced (CE) MRI provides in vivo physiological information that cannot be obtained by conventional imaging methods. This information is generally extracted by using models to represent the circulation of contrast agent in the body. However, the results depend on the quality of the fit obtained with the chosen model. Therefore, one must check the fit quality to avoid working on physiologically irrelevant parameters. In this study two dimensionless criteria—the fraction of modeling information (FMI) and the fraction of residual information (FRI)—are proposed to identify errors caused by poor fit. These are compared with more conventional criteria, namely the quadratic error and the correlation coefficient, both theoretically and with the use of simulated and real CE‐MRI data. The results indicate the superiority of the new criteria. It is also shown that these new criteria can be used to detect oversimplified models. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Axial asymmetry of water diffusion in brain white matter
Authors: Lazar Mariana , Lee Jong Hoon , Alexander Andrew L.
Published: September 2005

The diffusion tensor (DT) is a three‐dimensional (3D) model of diffusivity in biological tissues. In white matter (WM), the major eigenvector, which is the direction of greatest diffusivity, is generally assumed to align with the direction of the fiber bundles. The distribution of major eigenvectors in WM has been investigated using color‐based maps and WM tractography (WMT). However, anatomical patterns in the medium and minor eigenvector directions have largely been ignored in DTI studies of the human brain. In this study, the patterns of medium and minor eigenvectors in the brain were investigated using both color‐based maps and WMT. Specific WM structures, such as the corona radiata, internal and external capsules, sagittal stratum, cingulum, and superior longitudinal fasciculus, demonstrated coherent patterns in the medium and minor eigenvector directions. These patterns were consistent across subjects. The orthogonal or axial diffusion asymmetry may be explained by merging, diverging, or crossing fiber geometries. The effects of orthogonal diffusion asymmetry on WMT were also investigated. This study shows that WM axial asymmetry causes anisotropic dispersion patterns in the estimated tract trajectories. The medium and minor eigenvector patterns may be useful for elucidating the local dispersion distributions of WM tracts. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Matrix description of general motion correction applied to multishot images
Authors: Batchelor P. G. , Atkinson D. , Irarrazaval P. , Hill D. L. G. , Hajnal J. , Larkman D.
Published: September 2005

Motion of an object degrades MR images, as the acquisition is time‐dependent, and thus k‐space is inconsistently sampled. This causes ghosts. Current motion correction methods make restrictive assumptions on the type of motions, for example, that it is a translation or rotation, and use special properties of k‐space for these transformations. Such methods, however, cannot be generalized easily to nonrigid types of motions, and even rotations in multiple shots can be a problem. Here, a method is presented that can handle general nonrigid motion models. A general matrix equation gives the corrupted image from the ideal object. Thus, inversion of this system allows us to get the ideal image from the corrupted one. This inversion is possible by efficient methods mixing Fourier transforms with the conjugate gradient method. A faster but empirical inversion is discussed as well as methods to determine the motion. Simulated three‐dimensional affine data and two‐dimensional pulsation data and in vivo nonrigid data are used for demonstration. All examples are multishot images where the object moves between shots. The results indicate that it is now possible to correct for nonrigid types of motion that are representative of many types of patient motion, although computation times remain an issue. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Motor‐induced transcription but sensory‐regulated translation of ZENK in socially interactive songbirds
Authors: Whitney Osceola , Johnson Frank
Published: September 2005

The ZENK gene, depending upon singing activity, is transcribed within all the telencephalic nuclei controlling vocal behavior in songbirds. We show here that singing by deafened or completely isolated adult zebra finches induced high levels of ZENK transcription. This mRNA however, was not translated into high levels of ZENK protein. Instead, high levels of singing‐driven ZENK protein translation were found in socially interactive birds. This dissociation between ZENK mRNA and ZENK protein was regionally specific to the robust nucleus of the arcopallium (RA), a region that is well known for its control of vocal‐motor behavior in birds. Our results suggest cooperation between motor and sensory processes for regulating mRNA induction and subsequent protein synthesis in socially active songbirds. © 2005 Wiley Periodicals, Inc. J Neurobiol, 2005
Distribution and onset of retinaldehyde dehydrogenase (zRalDH) expression in zebra finch brain: Lack of sex difference in HVC and RA at early posthatch ages
Authors: Kim Yong‐Hwan , Arnold Arthur P.
Published: September 2005

Using in situ hybridization to detect the expression of the retinoic acid synthesizing enzyme (retinaldehyde dehydrogenase: zRalDH) mRNA, we mapped the distribution of its expression in adult zebra finch brain. In the neural song circuit, strong expression was found in high vocal center (HVC), para‐HVC, and at a very low level in the robust nucleus of the arcopallium (RA). The expression in HVC and RA was found in both males and females. Outside of the song system, major areas of expression were in medial nidopallium (N), hyperpallium apicale (HA), mesopallium ventrale (MV), taenial amygdala (TnA), cerebellar Purkinje cells, and nucleus isthmo‐opticus (IO). In nestlings, we found zRalDH mRNA expression in HVC and RA as early as posthatch day 4 or 5 (P4–5), although the expression varied among individuals. Thus, retinoic acid synthesis in HVC and RA could participate in song system formation and development. However, we found no sex difference in volume or intensity of zRalDH and androgen receptor (AR) expression in HVC and RA at P11 prior to the development of significant size dimorphisms in these nuclei. The size of HVC in females at P11 defined by zRalDH expression was greater than that in adult females, suggesting that HVC might experience net cell loss between P11 and adulthood. © 2005 Wiley Periodicals, Inc. J Neurobiol, 2005
Intraspinal and intracranial hemorrhage after lumbar puncture
Authors: Lee Anselm C.W. , Lau Yu , Li C.H. , Wong Y.C. , Chiang Alan K.S.
Published: September 2005

Two cases of spinal epidural hematoma and two cases of intracranial subdural hematoma after lumbar puncture (LP) are reported in children receiving chemotherapy for acute lymphoblastic leukemia and non‐Hodgkin lymphoma. The bleeding was asymptomatic but interfered with treatment in one case, and caused either severe backache or headache but no neurological deficit in the other three patients. The platelet counts were 8 and 46 × 109/L in two patients and were normal in the other patients at the time of LP. All recovered without surgical treatment. There is an inherent, albeit uncommon, risk of bleeding into the central nervous system associated with LP in children with cancer and should be distinguished from postdural puncture headache (PDPH). Thrombocytopenia is not always an accompanying factor. Pediatr Blood Cancer 2007;48:233–237. © 2006 Wiley‐Liss, Inc.
Proteomic analysis of rice embryo: An approach for investigating Gα protein‐regulated proteins
Authors: Komatsu Setsuko , Abbasi Fida , Kobori Eiko , Fujisawa Yukiko , Kato Hisaharu , Iwasaki Yukimoto
Published: September 2005

The rice dwarf1 (d1) mutant, which lacks the α subunit of a heterotrimeric G protein (Gα protein), shows abnormal morphology due to shortened internodes, dark green leaves and grains that are small and round. Proteome analysis was used in this study to aid in determining the function of Gα protein in rice embryos. Using 2‐DE, seven seed embryo proteins were shown to be down‐regulated in the d1 mutant as compared with its wild type. These seven proteins included a receptor for activated C‐kinase (RACK) and six rice embryo globulin‐2 proteins (REG2). The six REG2 have similar molecular masses with minor differences in pI. In addition to the reduced accumulation of RACK in the d1 mutant, the increase in QL/d1, in which a constitutively active form of the Gα protein is expressed, was significantly higher as compared with wild type. The level of accumulation of these seven proteins during seed development and maturation did not change significantly until the 2nd wk after pollination. Reduced accumulation of these seven proteins started in the d1 mutant at the 3rd wk after pollination, and continued until seed maturation was complete. All seven proteins were completely absent 24 h after imbibition in both d1 mutant and its wild type. However, the phytohormone abscisic acid promoted the expression level of RACK after imbibition in the wild type as compared with d1 mutant. These results suggest that RACK is regulated by Gα‐protein and plays an important role in a basic cellular process as well as in rice embryogenesis and germination.
In situ superconducting MgB2 films grown by co‐evaporation technique
Authors: Malisa Anayesu
Published: September 2005

Superconducting thin films of MgB2 were grown in situ by co‐evaporation of magnesium and boron on MgO (111), SiC (0001) and Al2O3 (0001) substrates at ∼300 °C. The films showed transitions to the superconducting state in the temperature range of 33–37 K. The widths of the superconducting transitions were less than 1 K. The films exhibited growth in the c‐axis and absence of other phases. Optimization of the growth parameters enabled films with smooth surface morphology and root‐mean‐square (RMS) roughness of 2 nm to be grown. The low RMS roughness value indicates that the technique can be used to grow MgB2 films useful for junctions and multilayer devices. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Normalization of relative peptide ratios derived from in‐gel digests: applications to protein variant analysis at the peptide level
Authors: Bergen H. Robert , Muddiman David C. , O'Brien John F. , Hoyer James D.
Published: September 2005

The ability to detect protein variants and post‐translational modifications by mass spectrometry has become increasingly important. Unfortunately, the ability to detect variants in large intact proteins (>80 000 Da) is limited. Even in the analysis of smaller proteins, algorithms are required to determine the presence of a 2 Da mass shift in an intact 13 kDa protein because the isotopic distribution of the multiply charged ions of the variant overlaps the wild‐type distribution. Fortunately, most modern instruments are capable of detecting variants in tryptic peptides derived from intact proteins. If a single common variant protein is known, the presence of a variant tryptic peptide can be easily demonstrated. A more difficult issue is the case where a multiplicity of peptides with multiple amino acid substitutions can be associated with pathology. In these cases a decrease in the relative amount of a variant peptide relative to other internal tryptic fragments would be diagnostic. However, the variability associated with the analysis of in‐gel or solution digests of proteins, related to efficiencies in digestion, extraction and ionization, confounds variant analysis at the peptide level. A strategy was developed to normalize for this variability by utilizing multiple isotopically labeled internal standards for multiple peptides derived from the same protein. Erythrocyte spectrin from 36 normal and 25 abnormal osmotic fragility samples was analyzed as a test case. Three isotopically labeled target peptides comprising the α/β‐spectrin self‐association sites were added to purified digested α‐spectrin. The utilization of multiple internal standards demonstrates the capability to normalize for sample variability due to ionization efficiency, solvent effects, digestion and extraction efficiency. Copyright © 2005 John Wiley & Sons, Ltd.
Fetal head‐to‐trunk volume ratio in chromosomally abnormal fetuses at 11 + 0 to 13 + 6 weeks of gestation
Authors: Falcon O. , Cavoretto P. , Peralta C. F. A. , Csapo B. , Nicolaides K. H.
Published: September 2005

Objective

To determine the pattern of early growth disturbance in chromosomally abnormal fetuses by comparing the volume of the fetal head to that of the trunk.

Methods

The fetal trunk and head volume was measured using three‐dimensional (3D) ultrasound in 145 chromosomally abnormal fetuses at a median gestational age of 12 (range, 11 + 0 to 13 + 6) weeks. The head volume was measured separately and then subtracted from the total head and trunk volume to obtain the volume of the fetal trunk. The head‐to‐trunk ratios were then calculated and the Mann–Whitney U‐test was used to determine the significance of differences from 500 chromosomally normal fetuses.

Results

The fetal head volume for crown–rump length (CRL) was significantly smaller than normal in trisomy 21, trisomy 13 and Turner syndrome (P < 0.001, P < 0.001 and P = 0.001, respectively), whereas no significant differences were found in trisomy 18 and triploidy (P = 0.139 and P = 0.070, respectively). The fetal trunk volume for CRL was significantly smaller in all chromosomal abnormalities (P < 0.001) except Turner syndrome (P = 0.134). The head‐to‐trunk ratio for CRL was significantly larger in trisomy 18, trisomy 13 and triploidy (P < 0.001), but normal in trisomy 21 (P = 0.221) and Turner syndrome (P = 0.768).

Conclusions

In trisomy 21 and Turner syndrome, the growth deficit was symmetrical with the head and trunk being equally affected, whereas in triploidy and trisomies 18 and 13 there was asymmetrical growth restriction with the trunk being more severely compromised than the head. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Correlation of presenting symptoms and patient characteristics with endometrial cancer prognosis in Japanese women
Authors: Kodama J. , Seki N. , Ojima Y. , Nakamura K. , Hongo A. , Hiramatsu Y.
Published: September 2005

Objective

To determine whether patient characteristics and presenting symptoms could be prognostic indicators for endometrial cancer in Japanese women.

Methods

Review of the medical charts, which included presenting symptoms and other patient characteristics, of 242 women who underwent surgical treatment for FIGO stage I–IV endometrial cancer.

Results

FIGO stage, histologic grade, and lower abdominal pain were found to be significant independent factors for progression‐free and overall survival. In contrast, abnormal uterine bleeding, comorbidities, and prior malignancy were not found to be prognostic factors.

Conclusion

Lower abdominal pain was found to be an independent prognostic factor in endometrial cancer among Japanese women.
History of Midwifery in New Mexico: Partnership Between Curandera‐parteras and the New Mexico Department of Health
Authors: Ortiz Felina Mychelle
Published: September 2005

Curandera‐parteras (traditional Hispanic midwives) have been in northern New Mexico since before its statehood. In the 1930s, the New Mexico Department of Health began a valuable relationship with the curandera‐parteras through the Midwife Consultant Program. This article describes the relationship between the curandera‐parteras and the New Mexico Department of Health originating in the 1920s. The amenable and effective working relationship achieved between curandera‐parteras and public health during this time period helped create the positive support for midwifery that is apparent in New Mexico today.
Why Do Women Miss Oral Contraceptive Pills? An Analysis of Women's Self‐Described Reasons for Missed Pills
Authors: Smith Janice D. , Oakley Deborah
Published: September 2005

Inconsistent use of oral contraceptives (OCs) exposes women to risks of unintended pregnancy. This study explored women's self‐described reasons for missed OC pills. Data from diary cards completed by 141 women were studied to see how reasons for missing pills were related to patterns of pill use. The findings suggest that practitioners might improve OC use by focusing on the reasons that women miss pills, thus providing a more tailored approach that addresses individual risks based on women's personal experiences.