bluuebunny/crossref_metadata_2025 huggingface dataset:
Gum mastic inhibits the expression and function of the androgen receptor in prostate cancer cells
Authors: He Mei‐Lan , Yuan Hui‐Qing , Jiang An‐Li , Gong Ai Yu , Chen Wei‐Wen , Zhang Peng‐Ju , Young Charles Y. F. , Zhang Jian‐Ye
Published: May 2006

Accumulating evidence suggests that the androgen receptor (AR) may play an important role in the development and progression of prostate cancer. To find new, useful compounds that effectively may attenuate the function of AR in prostate cancer cells, the authors investigated the effect of gum mastic, a natural resin, on AR activity. An androgen‐responsive prostate cancer cell line LNCaP was used as a model for this study. Gene transfer, reverse transcriptase‐polymerase chain reaction analysis, electrophoretic mobility shift assay, and Western blot analysis were used to test the effect of gum mastic on the expression and function of the AR. To demonstrate the inhibitory effect of gum mastic on the function of the AR, the expression of androgen‐regulated genes, including prostate‐specific antigen (PSA), human kallikrein 2 (hK2), and NKX3.1 were measured. In addition, transient transfection assays with the PSA promoter and the AR promoter also were used to test the effects of mastic. The results showed that gum mastic inhibited the expression of the AR at the transcriptional level, resulting in the down‐regulation of both AR messenger RNA and protein levels. Therefore, the function of the AR was inhibited, as reflected by the reduced expression of NKX3.1 and PSA and by androgen‐stimulated growth. Because gum mastic exhibited a strong in vitro potency to attenuate the expression and function of the AR, further investigation will be required to determine whether this naturally occurring substance has in vivo potency to inhibit prostate cancer development. Cancer 2006. © 2006 American Cancer Society.
A nonsynonymous single‐nucleotide polymorphism in the PDZ‐Rho guanine nucleotide exchange factor (Ser1416Gly) modulates the risk of lung cancer in Mexican Americans
Authors: Gu Jian , Wu Xifeng , Dong Qiong , Romeo Martin J. , Lin Xin , Gutkind J. Silvio , Berman David M.
Published: May 2006

BACKGROUND

Based on in vitro studies, Rho guanine nucleotide exchange factors (RhoGEFs) are key regulators of mitogenic and transforming pathways. At least 1 family member, PDZ‐RhoGEF, also integrates signaling between monomeric Rho G proteins and heterotrimeric G proteins through a so‐called regulator of G‐protein signaling (RGS) domain. Recently, the authors reported that 3 single‐nucleotide polymorphisms (SNPs) in 2 members of the RGS family were associated with significant reductions in the risk of cancer.

METHODS

For the current report, the authors studied the risk of lung cancer associated with a nonsynonymous SNP (rs868188; Ser1416Gly) in PDZ‐RhoGEF in a large lung cancer case‐control study of 2260 Caucasians and 369 Mexican Americans.

RESULTS

Compared with individuals who had the wild‐type genotype (AA), Mexican Americans with the variant genotypes (AG and GG) had a significantly reduced risk for lung cancer (odds ratio [OR], 0.57; 95% confidence interval [95%CI], 0.34‐0.94). The protective effect appeared to be more evident in younger individuals (OR, 0.42; 95%CI, 0.20‐0.91), men (OR, 0.36; 95%CI, 0.18‐0.71), and ever smokers (OR, 0.50; 95%CI, 0.29‐0.88). A joint effect was observed between Ser1416Gly and polymorphisms in 2 cell‐cycle control genes: p53 (intron 3) and cyclin D1 (CCND1). Tallying the variant alleles of the 4 RGS gene SNPs, a gene‐dosage effect was apparent. Compared with individuals who had <3 variant alleles, patients with ≥3 variant alleles had a 51% reduction in lung cancer risk (OR, 0.49; 95%CI, 0.28‐0.88).

CONCLUSIONS

To the authors' knowledge, this is the first epidemiological study to link PDZ‐RhoGEF polymorphisms with cancer risk. The results suggest that there are interactions between RGS2, RGS6, and PDZ‐RhoGEF and validate this family of proteins as key regulators of tumorigenesis. Cancer 2006. © 2006 American Cancer Society.
Cerebral metastases pathology after radiosurgery
Authors: Szeifert Gyorgy T. , Atteberry Dave S. , Kondziolka Douglas , Levivier Marc , Lunsford L. Dade
Published: May 2006

BACKGROUND

To the authors' knowledge, comprehensive human pathologic investigations that explore fundamental radiosurgical effects on metastatic brain tumors are sparse in the literature. The objective of this study was to analyze histopathologic findings in a set of clinically recurrent cerebral metastases after patients underwent stereotactic radiosurgery (SRS).

METHODS

In a series of 7500 patients who underwent radiosurgery, 2020 patients (27%) harbored cerebral metastases. Eighteen of 2020 patients (0.9%) underwent subsequent craniotomy for tumor removal anywhere from 1 month to 59 months after they received high‐dose irradiation. Histologic and immunohistochemical investigations were performed on the surgically resected tissue specimens. These specimens were within the radiosurgical treatment volume of the metastatic tumor.

RESULTS

Light microscopy revealed 3 basic categories of histologic responses: acute‐type, subacute‐type, and chronic‐type tissue reactions. A moderate‐to‐intense inflammatory cell reaction was seen in the tissue responses of well controlled neoplasms (i.e., in patients who had neoplasms that required craniotomy for recurrent disease >5 months after SRS), whereas the inflammatory reaction was missing or sparse in poorly controlled neoplasms (patients who required craniotomy for recurrent disease <5 months after SRS). This reaction was seen within the irradiated tumor volume and not in the peritumoral area nor in areas remote from the radiosurgical treatment volume. Immunohistochemical characterization demonstrated the presence of prominent CD68‐positive macrophage and CD3‐positive T‐lymphocyte populations. A progressively severe vasculopathy also was observed with increasing time after radiosurgery.

CONCLUSIONS

Although causality has not been established, a brisk inflammatory response and more severe vasculopathy were observed in lesions in which recurrences were more delayed. Cancer 2006. © 2006 American Cancer Society.
Treatment options in lymph node‐positive prostate cancer
Authors: Swanson Gregory P. , Thompson Ian M. , Basler Joseph
Published: May 2006

With improved awareness and screening, the incidence of lymph node‐positive prostate cancer has declined dramatically over the last 50 years. Stage of cancer, prostate‐specific antigen, and grade are risk factors for positive lymph nodes; and those factors, along with the number of involved lymph nodes, are prognostic factors for outcome. Although the numbers have declined, the number of men with lymph node‐positive prostate cancer remains significant, and the current challenge is how best to treat these patients. Commonly used treatments include any combination of androgen ablation, surgery, and radiation. There have been a few studies with chemotherapy, and no treatment has been proven superior to the others. Consequently, there remain several reasonable alternatives to treatment, and long‐term survival is not unusual. Cancer 2006. © 2006 American Cancer Society.
Bone invasion in extremity soft‐tissue sarcoma
Authors: Ferguson Peter C. , Griffin Anthony M. , O'Sullivan Brian , Catton Charles N. , Davis Aileen M. , Murji Ally , Bell Robert S. , Wunder Jay S.
Published: May 2006

BACKGROUND

The purpose of the current study was to evaluate histologic bone invasion as a predictor of oncologic outcome in extremity soft‐tissue sarcoma (STS) patients presenting to a specialty sarcoma center between 1986 and 2001.

METHODS

All patients who underwent surgery for extremity STS were identified from the prospective database at the study institution. Patient demographic features were compared using chi‐square analyses or independent‐sample Student t‐tests. The disease outcomes were compared for those with and without bone invasion using Kaplan–Meier survival analysis and Cox modeling.

RESULTS

In a review of 874 patients with STS of the extremity, 48 patients (5.5%) had evidence of bone invasion. Patients with bone invasion presented with larger tumors that were more frequently deep in the extremity and more often had metastases at presentation. Patients with bone invasion had lower metastasis‐free survival but bone invasion was not found to be an independent prognostic factor (P = .274) on Cox modeling. Bone invasion was found to be prognostic of overall survival on multivariate analysis (P<.0001).

CONCLUSIONS

In a small percentage of patients with STS, bone resection may be required to obtain an adequate surgical margin, thereby limiting the risk of local tumor recurrence. Histologic bone invasion portends a poorer prognosis in terms of overall survival. Cancer 2006. © 2006 American Cancer Society.
Prospective evaluation of the prognostic relevance of molecular staging for urothelial carcinoma
Authors: Copp Hillary L. , Chin Joseph L. , Conaway Mark , Theodorescu Dan
Published: May 2006

BACKGROUND

Nearly 50% of urothelial carcinoma patients with lymph node‐negative invasive cancers recur after radical surgery. In many cases, occult local or lymph node disease may be present but undetectable by current approaches. Reverse‐transcriptase polymerase chain reaction (RT‐PCR)‐detectable mRNA of Uroplakin II (UPII), a urothelial‐specific gene mRNA, was evaluated in perivesical and lymph node samples removed at radical surgery as a predictor of clinical recurrence.

METHODS

From November 1999 to August 2002, 46 patients with cTa‐T4N0M0 urothelial bladder cancer enrolled in a prospective clinical trial and underwent radical cystectomy and pelvic lymphadenectomy. RT‐PCR for UPII was performed on biopsies of the external surface of the bladder specimen and lymph nodes. Results were compared with conventional pathology. Patients were followed every 6 months for tumor recurrence.

RESULTS

Pathologically node‐negative patients had a UPII RT‐PCR perivesical positivity of 27% and a lymph node positivity rate of 33%. All 22 UPII RT‐PCR node‐negative patients were pathologically node‐negative and all 13 with pathologically positive nodes had positive UPII RT‐PCR lymph node signals. In all, 46% of UPII RT‐PCR lymph node‐positive patients were pathologically node‐negative and 5% of pathologically node‐negative/UPII RT‐PCR node‐negative patients had disease recurrence, whereas 91% of pathologically node‐negative/UPII RT‐PCR node‐positive patients (P<.001) recurred. UPII RT‐PCR node positivity was a significant predictor of tumor recurrence in multivariate analysis

CONCLUSIONS

Molecular determination of lymph node metastases by UPII RT‐PCR node positivity apparently identifies patients with a poor prognosis and may be more predictive of disease recurrence than conventional pathologic analysis. Cancer 2006. © 2006 American Cancer Society.
Foxg1 is required for morphogenesis and histogenesis of the mammalian inner ear
Authors: Pauley Sarah , Lai Eseng , Fritzsch Bernd
Published: May 2006

The forkhead genes are involved in patterning, morphogenesis, cell fate determination, and proliferation. Several Fox genes (Foxi1, Foxg1) are expressed in the developing otocyst of both zebrafish and mammals. We show that Foxg1 is expressed in most cell types of the inner ear of the adult mouse and that Foxg1 mutants have both morphological and histological defects in the inner ear. These mice have a shortened cochlea with multiple rows of hair cells and supporting cells. Additionally, they demonstrate striking abnormalities in cochlear and vestibular innervation, including loss of all crista neurons and numerous fibers that overshoot the organ of Corti. Closer examination shows that some anterior crista fibers exist in late embryos. Tracing these fibers shows that they do not project to the brain but, instead, to the cochlea. Finally, these mice completely lack a horizontal crista, although a horizontal canal forms but comes off the anterior ampulla. Anterior and posterior cristae, ampullae, and canals are reduced to varying degrees, particularly in combination with Fgf10 heterozygosity. Compounding Fgf10 heterozygotic effects suggest an additive effect of Fgf10 on Foxg1, possibly mediated through bone morphogenetic protein regulation. We show that sensory epithelia formation and canal development are linked in the anterior and posterior canal systems. Much of the Foxg1 phenotype can be explained by the participation of the protein binding domain in the delta/notch/hes signaling pathway. Additional Foxg1 effects may be mediated by the forkhead DNA binding domain. Developmental Dynamics 235:2470–2482, 2006. © 2006 Wiley‐Liss, Inc.
αN‐catenin deficiency causes defects in axon migration and nuclear organization in restricted regions of the mouse brain
Authors: Uemura Masato , Takeichi Masatoshi
Published: May 2006

αN‐catenin is a cadherin‐binding protein, widely expressed in the nervous system; and it plays a crucial role in cadherin‐mediated cell‐cell adhesion. Here we report the effects of αN‐catenin gene deficiency on brain morphogenesis. In addition to the previously reported phenotypes, we found that some of the axon tracts did not normally develop, in particular, axons of the anterior commissure failed to cross the midline, migrating, rather, to ectopic places. In restricted nuclei, a population of neurons was missing or their laminar arrangement was distorted. The ventricular structures were also deformed. These results indicate that αN‐catenin has diverse roles in the organization of the central nervous system, but only in limited portions of the brain. Developmental Dynamics 235:2559–2566, 2006. © 2006 Wiley‐Liss, Inc.
Geometrically Homogenous Series of Covalently Linked Zinc/Free‐Base Porphyrin Dimers of Varying Length; Design, Synthesis and Characterization
Authors: Ljungdahl Thomas , Pettersson Karin , Albinsson Bo , Mårtensson Jerker
Published: May 2006

Singlet excitation energy transfer, SEET, can be mediated by a bridge, connecting an energy donor and acceptor, via a superexchange mechanism. The mediation efficiency depends on the energy difference between the first excited states of the donor and the bridge, ΔEDB, as well as the donor–acceptor distance, RDA. We have previously constructed a series of donor–bridge–acceptor, D–B–A, systems that allowed us to study how SEET depends on ΔEDB. To expand this study into a second dimension, the distance dependence, a new series of D–B–A systems were constructed. This series was based on the same zinc/free‐base porphyrin couple as the donor–acceptor pair in the previous series. Their relative orientation was also retained. In contrast to our first series, the bridges in the latter were of varying length. The bridges were oligo(phenyleneethynylene)phenylene (OPE) structures and the length was systematically changed by increasing the number of phenyleneethynylene units from 1 to 4. To obtain high quality samples, the D–B–A systems were assembled by a building block approach where the zinc and free‐base porphyrins were introduced separately using Heck alkynylations. The performance of the OPE structure as a mediator and scaffold is discussed in terms of singlet excited state energies and flexibility. For the first time, when combining the topical D–B–A systems with our previous subset, a homogeneous series of D–B–A systems has been synthesized that allows for studies of both the distance dependence and the energy difference dependence of SEET. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Altered immune response to CNS viral infection in mice with a conditional knock‐down of macrophage‐lineage cells
Authors: Carmen Jessica , Gowing Genevieve , Julien Jean‐Pierre , Kerr Douglas
Published: May 2006

Neuroadapted Sindbis Virus (NSV) is a neuronotropic virus that causes hindlimb paralysis in susceptible mice and rats. The authors and others have demonstrated that though death of infected motor neurons occurs, bystander death of uninfected neurons also occurs and both contribute to the paralysis that ensues following infection. The authors have previously shown that the treatment of NSV‐infected mice with minocycline, an inhibitor that has many functions within the central nervous system (CNS), including inhibiting microglial activation, protects mice from paralysis and death. The authors, therefore, proposed that microglial activation may contribute to bystander death of motor neurons following NSV infection. Here, the authors tested the hypothesis using a conditional knock‐out of activated macrophage‐lineage cells, including endogenous CNS macrophage cells. Surprisingly, ablation of these cells resulted in more rapid death and similar weakness in the hind limbs of NSV‐infected animals compared with that of control animals. Several key chemokines including IL‐12 and monocyte chemoattractant protein‐1 (MCP‐1) did not become elevated in these animals, resulting in decreased infiltration of T lymphocytes into the CNS of the knock‐down animals. Either because of the decreased macrophage activation directly or because of the reduced immune cell influx, viral replication persisted longer within the nervous system in knock‐down mice than in wild type mice. The authors, therefore, conclude that although macrophage‐lineage cells in the CNS may contribute to neurodegeneration in certain situations, they also serve a protective role, such as control of viral replication. © 2006 Wiley‐Liss, Inc.
Reconstruction of the columella using the prefabricated reverse flow submental flap: A case report
Authors: Tan Onder , Kiroglu Ahmet Faruk , Atik Bekir , Yuca Koksal
Published: May 2006

Background.

The reconstruction of columellar defects is still a challenging procedure because of limited local and regional flap options and the characteristics of the anatomy of this site. Although a number of methods are available to repair nasal columella defects, no treatment of choice ensuring an excellent texture‐ and color‐matched tissue in one stage has been determined to date.

Method.

In this case, we used a reverse‐flow submental island flap prefabricated with the costal cartilage for the reconstruction of a complex columellar defect.

Result.

The flap survived completely with reversible venous congestion. The cosmetic result and nasal respiratory function were acceptable during the follow‐up time of 6 months.

Conclusion.

We propose that the prefabricated reverse submental flap may be an alternative among the surgical options for columellar defects. This flap may also be considered in the reconstructive repertoire of other composite defects of the head and neck region. © 2006 Wiley Periodicals, Inc. Head Neck, 2006
RM1: A reparameterization of AM1 for H, C, N, O, P, S, F, Cl, Br, and I
Authors: Rocha Gerd B. , Freire Ricardo O. , Simas Alfredo M. , Stewart James J. P.
Published: May 2006

Twenty years ago, the landmark AM1 was introduced, and has since had an increasingly wide following among chemists due to its consistently good results and time‐tested reliability—being presently available in countless computational quantum chemistry programs. However, semiempirical molecular orbital models still are of limited accuracy and need to be improved if the full potential of new linear scaling techniques, such as MOZYME and LocalSCF, is to be realized. Accordingly, in this article we present RM1 (Recife Model 1): a reparameterization of AM1. As before, the properties used in the parameterization procedure were: heats of formation, dipole moments, ionization potentials and geometric variables (bond lengths and angles). Considering that the vast majority of molecules of importance to life can be assembled by using only six elements: C, H, N, O, P, and S, and that by adding the halogens we can now build most molecules of importance to pharmaceutical research, our training set consisted of 1736 molecules, representative of organic and biochemistry, containing C, H, N, O, P, S, F, Cl, Br, and I atoms. Unlike AM1, and similar to PM3, all RM1 parameters have been optimized. For enthalpies of formation, dipole moments, ionization potentials, and interatomic distances, the average errors in RM1, for the 1736 molecules, are less than those for AM1, PM3, and PM5. Indeed, the average errors in kcal · mol−1 of the enthalpies of formation for AM1, PM3, and PM5 are 11.15, 7.98, and 6.03, whereas for RM1 this value is 5.77. The errors, in Debye, of the dipole moments for AM1, PM3, PM5, and RM1 are, respectively, 0.37, 0.38, 0.50, and 0.34. Likewise, the respective errors for the ionization potentials, in eV, are 0.60, 0.55, 0.48, and 0.45, and the respective errors, in angstroms, for the interatomic distances are 0.036, 0.029, 0.037, and 0.027. The RM1 average error in bond angles of 6.82° is only slightly higher than the AM1 figure of 5.88°, and both are much smaller than the PM3 and PM5 figures of 6.98° and 9.83°, respectively. Moreover, a known error in PM3 nitrogen charges is corrected in RM1. Therefore, RM1 represents an improvement over AM1 and its similar successor PM3, and is probably very competitive with PM5, which is a somewhat different model, and not fully disclosed. RM1 possesses the same analytical construct and the same number of parameters for each atom as AM1, and, therefore, can be easily implemented in any software that already has AM1, not requiring any change in any line of code, with the sole exception of the values of the parameters themselves. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 1101–1111, 2006
Assessment for crisis intervention
Authors: Myer Rick A. , Conte Christian
Published: May 2006

This article describes the triage assessment system (TAS) for crisis intervention. The TAS assesses affective, behavioral, and cognitive reactions of individuals to crisis events. This assessment model offers clinicians an understanding of the type of reactions clients are experiencing as well as the intensity of these reactions. The TAS provides a quick, accurate, and easy‐to‐ use method that is directly usable in the intervention process. The system can also be used to monitor clients' progress during the intervention process. Two case illustrations are presented to demonstrate the use of the model. In addition, the Triage Assessment Form: Crisis Intervention is included as an Appendix. © 2006 Wiley Periodicals, Inc. J Clin Psychol: In Session 62: 959–970, 2006.
Noways tired: Perspectives of clinicians of color on culturally competent crisis intervention
Authors: Sullivan Martha Adams , Harris Ella , Collado Carmen , Chen Teddy
Published: May 2006

The authors demonstrate through case material the clinical benefits of utilizing a culturally competent approach to crisis intervention. The focus here is on intervention with racial/ethnic minorities, in particular Black Americans, Latino Americans and Asian Americans; but the authors also address the importance of culturally competent crisis intervention praxis for all clients. © 2006 Wiley Periodicals, Inc. J Clin Psychol: In Session 62: 987–999, 2006.
Psychotherapy for families in the aftermath of a disaster
Authors: Wells Michael E.
Published: May 2006

We have not seen the last of natural disasters; nor have we endured the last of the terrorist acts. This article offers clinical guidance in providing mental health services to families in the aftermath of such events. The trauma experienced by an individual victimized by a natural disaster or terror attack reverberates through an entire family. Although based in established clinical practice, intervention with survivors of disasters is a different process from other treatments. A case illustrates the key principles and central methods of family therapy with a traumatized family. © 2006 Wiley Periodicals, Inc. J Clin Psychol: In Session 62: 1017–1027, 2006.
Community mental health response to crisis
Authors: Gard Betsy A. , Ruzek Josef I.
Published: May 2006

Mental health is seen as an important aspect in the community response to crisis and disaster. Research offers limited guidance to what interventions are likely to be effective in preventing postdisaster mental health problems. This article reviews recommended elements of mental health responses to community disasters. Different factors influencing response are illustrated by using 9/11 and Hurricane Katrina as examples. Clinical suggestions for community planning and actions of individual psychologists conclude the article. © 2006 Wiley Periodicals, Inc. J Clin Psychol: In Session 62: 1029–1041, 2006.
Cover Picture: Macromol. Mater. Eng. 5/2006
Authors: Sahre Karin , Abd Elrehim Mona Hasan , Eichhorn Klaus‐Jochen , Voit Brigitte
Published: May 2006

Cover: The reaction of 2,4‐toluylene diisocyanate and diethanolamine, as an A2 + B*B2 polymerization system towards hyperbranched poly(urea‐urethane)s, was followed using in situ ATR‐FTIR spectroscopy. In addition to the decrease of the NCO band the formation of urethane and urea bands of the polymer was analyzed to describe the actual state of synthesis. Further details can be found in the article by K. Sahre,* M. H. Abd Elrehim, K.‐J. Eichhorn, and B. Voit on page 470.
Comparison of continuous and intermittent vibration effects on rat‐tail artery and nerve
Authors: Govindaraju Sandya R. , Curry Brian D. , Bain James L. W. , Riley Danny A.
Published: May 2006

Hand‐transmitted vibration from powered‐tools can cause peripheral vasospasm and neuropathy. A rat‐tail model was used to investigate whether the pattern of vibration influenced the type and severity of tissue damage. The tails of awake rats were vibrated continuously or intermittently for a total of 4 hours at 60 HZ, 49 m/s2. Nerves and arteries were harvested immediately or 24 hours after treatment. Tails subjected to intermittent vibration showed transiently increased sensitivity to thermal stimuli. Intermittent vibration caused the most nerve injury immediately and 24 hours after vibration. Continuous vibration invoked a persistent reduction in vascular lumen size. Compared to epinephrine‐induced transient vacuolation in vascular smooth muscle cells, both continuous and intermittent vibration caused greater persistence of vacuoles, indicating a vibration‐induced pathological process. All vibration groups exhibited elevated nitrotyrosine immunoreactivity indicative of free‐radical damage. Pattern of vibration exposure may exert a major influence on the type of vibration injury. Muscle Nerve, 2006
A viscoelastic model for the dynamic response of soils to periodical surface water disturbance
Authors: Hsieh P. C.
Published: May 2006

In many instances soils can be assumed to behave like viscoelastic materials during loading/unloading cycles, and this study is aimed at setting up a viscoelastic model to investigate the dynamic response of a porous soil layer of finite thickness under the effect of periodically linear water waves. The waves and homogeneous water are described by potential theory and the porous material is described by a viscoelastic model, which is modified from Biot's poroelastic theory (1956). The distributions of pore water pressures and effective stresses of various soils such as silt, sand, and gravel are demonstrated by employing the proposed viscoelastic model. The discrepancies of the dynamic response between the simulations of viscoelastic model and elastic model are found to be strongly dependent on the wave frequency. Copyright © 2006 John Wiley & Sons, Ltd.
Investigation of defects in GaN with varying Mg doping concentrations
Authors: Obata Toshiyuki , Matsumura Naoki , Ogiwara Kiyoshi , Hirayama Hideki , Aoyagi Yoshinobu , Ishibashi Koji
Published: May 2006

We report on the electrical and lattice properties of heavily Mg‐doped GaN in which the conductivity is inverted to n‐type, as grown by low‐pressure (LP) metalorganic chemical vapour deposition. We suggested that n‐type inverted conductivity is caused by self‐compensation effects induced by nitrogen vacancies, and not by unintentionally‐doped impurities such as oxygen or carbon by performing Hall‐effect and secondary‐ion‐mass spectroscopy (SIMS) measurements. We directly observed the configurations of N and Ga atoms in Mg‐doped GaN by using the Rutherford backscattering spectrometry (RBS)‐channeling method. We found that Mg‐doping causes the degradation of both the Ga and N lattice properties. We observed for the first time that the density or the lattice relaxation amplitude of N atoms was larger than that of Ga atoms. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication of thick AlN film by low pressure hydride vapor phase epitaxy
Authors: Liu Yu‐Huai , Tanabe Tomoaki , Miyake Hideto , Hiramatsu Kazumasa , Shibata Tomohiko , Tanaka Mutsuhiro
Published: May 2006

Thick AlN crystals were grown by conventional hydride vapor phase epitaxy (HVPE) on AlN/sapphire templates under low pressure (∼15 Torr) at high temperature (1100 °C–1200 °C). Colorless, mirror‐like AlN films were obtained at the growth rates of up to 20.6 μm/h. The best root mean square (RMS) value of atomic force microscope (AFM) observations for the AlN surface was 0.19 nm in a surface of 5×5 μm2. The typical values of full width half maximum (FWHM) of X‐ray rocking curves for (0002) and (10$ \bar 1 $2) diffraction of AlN films were 173–314 arcsec and 1574–1905 arcsec, respectively. We also investigated the influences of carrier gas, growth temperature and growth rate on the crystal quality. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mechanisms of bending of threading dislocations in MOVPE‐grown GaN on (0001) sapphire
Authors: Datta R. , Humphreys C. J.
Published: May 2006

In this article, we describe possible mechanisms associated with the bending of threading dislocations (TDs) through 90° in GaN. In‐situ ELOG using SiNx masking on a sapphire substrate and in‐situ SiNx interlayer (IL) deposition on a GaN pseudo‐substrate have been used to reduce the TD density in GaN. The bending of TDs through 90° is essential in order to reduce their numbers in the upper growing layer. The bending of TDs is facilitated by a change in growth mode, i.e. predominantly 2D to 3D and then 3D to 2D. A new mechanism is tentatively proposed which can explain the bending of all types of TDs (edge, screw, and mixed). This new mechanism is based on first, step formation at 3D island side facets when TDs terminate there, following which, depending on the subsequent change in growth mode (3D to 2D) and the direction of the atomic ledge movement, the TDs will bend over. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Appendectomy versus Antibiotic Treatment in Acute Appendicitis. A Prospective Multicenter Randomized Controlled Trial
Authors: Styrud Johan , Eriksson Staffan , Nilsson Ingemar , Ahlberg Gunnar , Haapaniemi Staffan , Neovius Gunnar , Rex Lars , Badume Ibrahim , Granström Lars
Published: May 2006

Background

Appendectomy has been the treatment for acute appendicitis for over 120 years. Antibiotic treatment has occasionally been used in small uncontrolled studies, instead of operation, but this alternative has never before been tried in a multicenter randomized trial.

Patients and Methods

Male patients, 18–50 years of age, admitted to six different hospitals in Sweden between 1996 and 1999 were enrolled in the study. No women were enrolled by decision of the local ethics committee. If appendectomy was planned, patients were asked to participate, and those who agreed were randomized either to surgery or to antibiotic therapy. Patients randomized to surgery were operated on with open surgery or laparoscopically. Those randomized to antibiotic therapy were treated intravenously for 2 days, followed by oral treatment for 10 days. If symptoms did not resolve within 24 hours, an appendectomy was performed. Participants were monitored at the end of 1 week, 6 weeks, and 1 year.

Results

During the study period 252 men participated, 124 in the surgery group and 128 in the antibiotic group. The frequency of appendicitis was 97% in the surgery group and 5% had a perforated appendix. The complication rate was 14% in the surgery group. In the antibiotic group 86% improved without surgery; 18 patients were operated on within 24 hours, and the diagnosis of acute appendicitis was confirmed in all but one patient, and he was suffering from terminal ileitis. There were seven patients (5%) with a perforated appendix in this group. The rate of recurrence of symptoms of appendicitis among the 111 patients treated with antibiotics was 14% during the 1‐year follow‐up.

Conclusions

Acute nonperforated appendicitis can be treated successfully with antibiotics. However, there is a risk of recurrence in cases of acute appendicitis, and this risk should be compared with the risk of complications after appendectomy.
Subtotal Thyroidectomy for Benign Multinodular Goiter: A 6‐Month Postoperative Study of the Remnant’s Function and Sonographic Aspect
Authors: Bakiri Fawzy , Hassaïm Menad , Bourouba Mohamed‐Sadreddine
Published: May 2006

Background

The purpose was to evaluate the thyroid function after subtotal thyroidectomy.

Methods

One hundred and nineteen patients operated on for multinodular benign goiter were included in this prospective study. Results of the surgical treatment were evaluated 6 months after operation by thyroid‐stimulating hormone (TSH) assay and cervical echography.

Results

Thyroid‐stimulating hormone levels correlated inversely (r = −0.78) with the thyroid remnant volumes. Forty‐seven patients presented with a hypoechoic aspect of the remnant. Isoechoic and hypoechoic remnant volumes were similar; however, 46 of the 47 patients with a hypoechoic remnant (97.9%) had TSH levels higher than 5 mU/l vs. 39 of the 72 patients (54.2%) with an isoechoic aspect. No predictive factor for the occurrence of this hypoechoic feature was found.

Conclusions

After sub‐total thyroidectomy for benign multinodular goiter, the volume of the remnant is not the only determinant of the occurrence of postoperative hypothyroidism. The appearance of a hypoechoic aspect of the remnant is also a strong predictive factor for such an outcome. In this case the occurrence of hypothyroidism is quite constant whatever the volume of the thyroid remnant. Since this evolution toward a hypoechoic aspect of the remnant is unpredictable, our results are an additional argument in favor of total thyroidectomy for benign multinodular goiter.
An Analysis of Risk Factors Associated with Failure of Below Knee Amputations
Authors: Yip Vincent S.K. , Teo Nee Beng , Johnstone Robert , Robertson Andrew G.N. , Robertson John H.P. , Welch George H. , Kettlewell Stephen
Published: May 2006

Background

Below knee amputation (BKA) is often required in patients with critical limb ischemia. When such a procedure fails, an above knee revision (AKA) is required. This can cause further complications in this group of patients, who already have a high incidence of medical co‐morbidities.

Methods

Case records of 47 patients (51 procedures performed) with BKA for peripheral vascular diseases during a 4‐year period were reviewed. Clinical factors were analyzed using bi‐ and multi‐variate analysis against the procedure outcome. Degree of social deprivation was evaluated with DEPCAT score in relation to amputation failure. Each arterial segment of the pre‐operative arteriograms was scored based on a 3‐point scoring system (0 = normal, 1 = stenosis, and 2 =occlusion). With the assignment of an arbitrary weight for each segment, a total arterial score (TAS) was derived for each patient.

Results

Eighteen percent of BKA (n = 9) failed. Absence of popliteal pulse (failure vs. success: 100% vs. 63%, P = 0.04), calf rest pain (67% vs. 20%, P = 0.01), combination of calf rest pain and feet tissue loss (CRPFTL; 67% vs. 3%, P = 0.00), postoperative stump trauma (44% vs. 10%, P = 0.03), and wound infection (WI; 89% vs. 26%, P = 0.00) were factors associated with the failure of a BKA in bivariate analysis. Using multiple logistic regression, WI (OR = 14) and CRPFTL (OR = 47) were found to be independent predictors for the outcome of BKA. No statistical significance was found between the DEPCAT score and the failure rate. TAS was significantly higher in the failure group (median = 17 vs. 9; P = 0.00).

Conclusions

This study suggests that CRPFTL and postoperative WI are predictor variables for the failure of a BKA. In addition, there is the potential role of arteriogram scoring in predicting the outcome of a BKA.
Contrastive seasonal changes in ecophysiological traits of leaves of two perennial Polygonaceae herb species differing in leaf longevity and altitudinal distribution
Authors: Sakata Tsuyoshi , Nakano Takashi , Iino Takanori , Yokoi Yota
Published: May 2006

To identify the leaf characteristics associated with the difference in altitudinal distribution of Polygonaceae plants, we investigated the seasonal changes in leaf characteristics of co‐occurring Aconogonum weyrichii and Reynoutria japonica at 2250 m a.s.l. on Mt. Fuji. Aconogonum weyrichii is distributed in the alpine region and R. japonica from the lowlands to the highlands. At the beginning of the growing period, leaves of A. weyrichii had larger amounts of nitrogen, Rubisco and higher photosynthetic capacity than R. japonica. The relationship between the amounts of nitrogen and Rubisco did not significantly differ between the species, but a higher Rubisco activity per unit Rubisco protein content was found in A. weyrichii, and was thought to be responsible for the high photosynthetic capacity of this species in summer. Activity of ascorbate peroxidase, a key enzyme of the hydrogen peroxide scavenging system against oxidative stress under chilling and light conditions, increased significantly in R. japonica late in the growing period, but did not significantly change in A. weyrichii. In A. weyrichii, rapid maturation of leaves and a high photosynthetic capacity are thought to be adaptive features for the short growing season in alpine regions. On the other hand, the slower accumulation of nitrogen and Rubisco during the early stage of the growing period in R. japonica resulted in insufficient utilization of the growing period for photosynthetic production and is thought to be one of the factors restricting the upper limit of its distribution.
Fatigue and anaemia in patients with chronic heart failure
Authors: Falk Kristin , Swedberg Karl , Gaston‐Johansson Fannie , Ekman Inger
Published: May 2006

Background:

Fatigue is common in patients with chronic heart failure (CHF) and has great impact on functional ability and daily activity. Although anaemia is associated with fatigue, the relationship between fatigue and anaemia is unclear in CHF. The aim of this study was to describe the fatigue experience and its relationship to haemoglobin (Hb) concentration and to evaluate its effect on health‐related quality of life in an unselected hospitalised CHF population.

Methods:

Ninety three consecutive patients hospitalised with a diagnosis of CHF, enrolled in the EuroHeart Failure Survey, completed the Multidimensional Fatigue Inventory Scale (MFI‐20). New York Heart Association (NYHA) functional class, quality of life and haemoglobin were also assessed.

Results:

Anaemia (Hb≤125 g/L) was found in 31 (33%) patients. The perception of fatigue differed significantly between patients with CHF and healthy individuals. Anaemic patients reported significantly more fatigue compared to non‐anaemic patients. Decreased haemoglobin and higher NYHA class explained 30% of the variance in General Fatigue. Perceived fatigue was also inversely related to global health and quality of life.

Conclusion:

Our findings suggest that the subjective experience of fatigue in patients with CHF is associated with low haemoglobin concentration and reduced functional status after controlling for age and sex.
The factor structure of the General Health Questionnaire (GHQ): a scaled version for general practice in Spain
Authors: Molina J.D. , Andrade-Rosa C. , González-Parra S. , Blasco-Fontecilla H. , Real M.A. , Pintor C.
Published: May 2006

Background

The 28-item version of the General Health Questionnaire (GHQ-28) developed by Goldberg and Hillier in 1979 is constructed on the basis of a principal components analysis of the GHQ-60. When used on a Spanish population, a translation of the GHQ-28 developed for an English population may lead to worse predictive values.

Methods

We used our Spanish sample to replicate the entire process of construction of the GHQ-28 administered in a primary-care setting.

Results

Two shorter versions were proposed: one with six scales and 30 items, and the other with four scales and 28 items.

Conclusions

The resulting GHQ-28 was a successful adaptation for use on the Spanish sample. When compared with the original version, only 21 items were the same. Moreover, contrary to the English version, which groups sleep problems and anxiety in the same scale, a scale with items related exclusively to ‘Sleep disturbances’ was found.
CYP4A11 is repressed by retinoic acid in human liver cells
Authors: Antoun Joseph , Amet Yolande , Simon Brigitte , Dréano Yvonne , Corlu Anne , Corcos Laurent , Salaun Jean Pierre , Plée-Gautier Emmanuelle
Published: May 2006

CYP4A11, the major fatty acid ω‐hydroxylase in human liver is involved in the balance of lipids, but its role and regulation are both poorly understood. We studied the effects of retinoids on the regulation of CYP4A11 in the human hepatoma cell line HepaRG. Treatment of HepaRG cells with all‐trans‐retinoic acid resulted in a strong decrease in CYP4A11 gene expression and apoprotein content and, furthermore, was associated with a 50% decrease in the microsomal lauric acid hydroxylation activity. Such a strong suppression of CYP4A11 expression by retinoids could have a major impact on fatty acid metabolism in the liver.
An essential role of Cdc42‐like GTPases in mitosis of HeLa cells
Authors: Yasuda Shingo , Taniguchi Hiroyuki , Oceguera-Yanez Fabian , Ando Yoshikazu , Watanabe Sadanori , Monypenny James , Narumiya Shuh
Published: May 2006

Here we used RNA interference and examined possible redundancy amongst Rho GTPases in their mitotic role. Chromosome misalignment is induced significantly in HeLa cells by Cdc42 depletion and not by depletion of either one or all of the other four Cdc42‐like GTPases (TC10, TCL, Wrch1 or Wrch2), four Rac‐like GTPases or three Rho‐like GTPases. Notably, combined depletion of Cdc42 and all of the other four Cdc42‐like GTPases significantly enhances chromosomal misalignment. These observations suggest that Cdc42 is the primary GTPase functioning during mitosis but that the other four Cdc42‐like GTPases can also assume the mitotic role in its absence.
Morphometric and gonad maturity in the spider crab Maja brachydactyla: a comparison of methods for estimating size at maturity in species with determinate growth
Authors: Corgos Antonio , Freire Juan
Published: May 2006

Ontogenetic changes in the relative growth of males and females of the spider crab Maja brachydactyla, a species with terminal moult and determinate growth, were analysed and related to their reproductive (maturity) status. Based on the allometry of cheliped size, two morphometric groups of males separated juvenile and adult phases. Juvenile males also showed two growth phases, immature (smaller ones, without spermatophores) and adolescent (with spermatophores). Size at gonad maturity in males (estimated as CL50) was 96.2 mm carapace length (CL). Histological analysis of males showed that >60% of morphometric juveniles and 100% of morphometric adults had spermatophores in the gonad. Females begin to develop gonads 2–3 months after the terminal moult. Size at morphometric maturity was estimated comparing two methodologies: the size at 50% maturity (CL50) and the median size of adult cohorts (CLM). In all cases the CLM size at maturity was greater than that resulting from the CL50 method, and, in contrast to the CL50 method, CLM was greater for females in all cases. Therefore, CLM reflects better the real size at maturity for M. brachydactyla. Owing to spatial segregation of adults and juveniles and the availability of morphological and morphometric methods to estimate maturity status, we suggest a combination of spatial closures and direct protection of juvenile habitat as management strategies alternative to minimum landing sizes.
Temperature variability and vertical vegetation belt shifts during the last ∼50,000 yr in the Qilian Mountains (NE margin of the Tibetan Plateau, China)
Authors: Herzschuh Ulrike , Kürschner Harald , Mischke Steffen
Published: May 2006

A 13.94-m-long sediment core, collected from a medium-sized lake in the Qilian Mountains (NE Tibetan Plateau, China), was analysed palynologically at 81 horizons. The interpretation of indicator taxa yielded various vertical shifts of the vegetation belts. These palaeovegetation results have been checked with lake surface pollen spectra from 8 lakes representing different altitudinal vegetation belts. Our main findings are the following: A short period of the late Marine Isotope Stage 3 (around ∼46,000 yr ago) was characterized by interglacial temperature conditions with a tree line above its present-day altitude. During the LGM, the vicinity of the lake was not covered by ice but by sparse alpine vegetation and alpine deserts, indicating that the climate was colder by ∼4–7°C than today. Markedly higher temperatures were inferred from higher arboreal pollen frequencies between ∼13,000 and ∼7,000 yr ago with a Holocene temperature optimum and a maximal Picea–Betula mixed-forest expansion between ∼9,000 and ∼7000 yr ago, when temperatures exceeded the present-day conditions by at least 1–2°C. Alpine steppes and meadows and sub-alpine shrub vegetation dominated around the lake since the middle Holocene, suggesting that vegetation and climate conditions were exceptionally stable in comparison to previous periods.
On the importance of antiparallel reconnection when the dipole tilt and IMF By are nonzero
Authors: Park K. S. , Ogino T. , Walker R. J.
Published: May 2006

Several parameters may influence reconnection at the dayside magnetopause. They include the relative orientation of the magnetic fields in the magnetosheath and magnetosphere, the relative perpendicular velocities of field lines both before and after reconnection, and the location of the minimum geomagnetic field. We have used a three‐dimensional global MHD simulation of the magnetosphere to evaluate the relative importance of these parameters at the dayside magnetopause, when the interplanetary magnetic field (IMF) has a By component and the dipole tilt is nonzero. For a purely southward IMF and finite tilt, reconnection occurs near the magnetic equator. The reconnection rate at the magnetic equator is smaller than the case with zero tilt because of increased magnetosheath plasma flow. For finite IMF By the reconnection sites move away from the subsolar point. When we include a positive dipole tilt, the reconnection site in the summer hemisphere shifts sunward and equatorward while the one in the winter hemisphere moves tailward and away from the equator. Reconnection near the magnetic equator becomes less effective because IMF field lines move rapidly past the magnetic equator for the finite tilt. We have evaluated the importance of antiparallel reconnection by calculating the electric field at the magnetopause and found that antiparallel reconnection is more important than component reconnection for cases with finite dipole tilt and an IMF By component.
Seasonal variability of the sea surface salinity in the East China Sea during 1990–2002
Authors: Chen Xianyao , Wang Xiuhong , Guo Jingsong
Published: May 2006

The seasonal distribution of the sea surface salinity (SSS) in the East China Sea (ECS) during 1990–2002 is examined based on a historical data set from the World Ocean Database 2001 (WOD2001), the data available from the Japan Oceanographic Data Center (JODC), and the cruise observations conducted by China during 1997–2002. The SSS data set has been mapped into a regular 0.25° by 0.25° grid for the study. It is shown that the largest SSS variation is at the area where the Changjiang River Diluted Water (CRDW) changes its flow directions due to the southerly wind in summer and northerly wind in fall. The variation is further complemented by the Changjiang River discharge that reaches its maximum in summer and minimum in winter. It is also shown that the seasonal variation of the evaporation minus precipitation (E‐P) has a secondary effect on the SSS distribution.