bluuebunny/crossref_metadata_2025 huggingface dataset:
Scanning tunneling microscope based fabrication of nano- and atomic scale dopant devices in silicon: The crucial step of hydrogen removal
Authors: Hallam T. , Reusch T. C. G. , Oberbeck L. , Curson N. J. , Simmons M. Y.
Published: February 2007

The use of a scanning tunneling microscope (STM) to pattern a hydrogen resist on the Si(001) surface has recently become a viable route for the fabrication of nanoscale planar doped devices in silicon. A crucial step in this fabrication process is the removal of the hydrogen resist after STM patterning before Si encapsulation of the dopants via molecular beam epitaxy. We compare thermal and STM-stimulated hydrogen desorptions in terms of surface morphology and integrity of dopant nanostructures embedded in the surface. We find that the boundaries of STM patterned P-in-Si nanostructures are maintained by STM-stimulated hydrogen desorption. In comparison, for an optimized thermal annealing at 470°C for 15s to remove the hydrogen there is a lateral diffusion out of the nanostructured region of up to ∼7–8nm. Our results demonstrate the advantages of nonthermal hydrogen desorption for the preservation of atomic scale dopant patterns in silicon.
Intense gigawatt relativistic electron beam generation in the presence of prepulse
Authors: Mondal J. , Kumar D. D. P. , Roy A. , Mitra S. , Sharma A. , Singh S. K. , Rao G. V. , Mittal K. C. , Nagesh K. V. , Chakravarthy D. P.
Published: February 2007

Large pulse power systems in the presence of prepulse can deliver gigawatt power pulses into a matched load. While employing these pulse power systems for the generation of intense relativistic electron beams (IREBs), the prepulse initiated plasma closes the anode cathode gap, if the gap distance is set by the Child-Langmuir formula. In order to reduce the prepulse effect, the anode cathode gap has been increased for the generation of IREB with output parameters of 400kV, 20kA, and 100ns pulse duration. In this paper the generation of IREB in the presence of prepulse without using any prepulse switch has been discussed.
Application of self-organization methods to current-induced magnetization dynamics of a single-domain ferromagnet
Authors: Gorley P. M. , Horley P. P. , Dugaev V. K. , Barnaś J. , Dobrowolski W.
Published: February 2007

Magnetization dynamics of a single-domain ferromagnet is studied theoretically using the methods developed for self-organization phenomena. Time evolution of the magnetization is described by the Landau-Lifshitz-Gilbert equation with the spin-transfer torque included. The equilibrium and stationary states are investigated as a function of spin current and external magnetic field. The presented bifurcation diagram allows the margins of a neutral stability mode of the equilibrium and stationary states to be determined. An envelope equation for the magnetization switching is derived. The switching time Δτ between different states is found to be comparable to the half-width of the time derivative of the system energy, which allows the energy flow due to spin current and the magnetization switching velocity to be related. Dynamics of the phase states in external magnetic field and in the presence of spin current is analyzed using different methods of numerical analysis.
Origin of ground state anomaly in LaB6 at low temperatures
Authors: Medicherla V. R. R. , Patil Swapnil , Singh Ravi Shankar , Maiti Kalobaran
Published: February 2007

The authors investigate the temperature evolution of the electronic structure of LaB6, a widely used material as high brightness cathode, using UV photoemission spectroscopy with state-of-the-art energy resolution (1.4meV) and band structure calculations in order to probe the origin of low temperature anomaly in its physical properties. Comparison of experimental and theoretical results suggests that electron correlation is not significant in this system and that the electronic states in the vicinity of the Fermi level, ϵF, possess mixed character. High resolution spectra at different temperatures T reveal a pseudogap for T<100K, which evolves gradually with the decrease in temperature.
Wnt signaling interacts with Shh to regulate taste papilla development
Authors: Iwatsuki Ken , Liu Hong-Xiang , Grónder Albert , Singer Meredith A. , Lane Timothy F. , Grosschedl Rudolf , Mistretta Charlotte M. , Margolskee Robert F.
Published: February 2007

Wnt and Shh signaling pathways are critical for the development and maturation of many epithelial tissues. Both pathways have roles in stem cell maintenance, tissue development, and tumorigenesis. However, linkage between these pathways in mammalian systems had not been well established. Here, we report that Shh expression in fungiform papillae and formation of normal mature fungiform papillae depend on signaling through Wnt and β-catenin. We observed that during fungiform papilla formation in mice, Shh and components of the Wnt/β-catenin signaling pathway are expressed together in the developing placode. The elimination of Wnt/β-catenin signaling in either Lef1 or Wnt10b knockout mice resulted in down-regulation of Shh expression. In addition, the size and number of fungiform papillae were greatly reduced in Lef1 knockout mice. By examining embryonic mouse tongues in culture we determined that activation of Wnt/β-catenin signaling up-regulates Shh expression. We observed that blocking Shh signaling in cultured tongue explants enhanced papillae formation and was accompanied by an up-regulation of Wnt/β-catenin signaling, indicating that Shh inhibits the Wnt/β-catenin pathway. Exogenously added Shh suppressed expression of endogenous Shh and inhibited Wnt/β-catenin signaling (assessed in TOPGAL mice), further implicating Shh as an inhibitor of the Wnt/β-catenin pathway. Our observations indicate that Wnt/β-catenin signaling and interactions between the Wnt and Shh pathways play essential roles in the development of fungiform papillae.
Morphological mechanism of the development of pulmonary emphysema in
klotho
mice
Authors: Sato Atsuyasu , Hirai Toyohiro , Imura Akihiro , Kita Naoko , Iwano Akiko , Muro Shigeo , Nabeshima Yo-ichi , Suki Bela , Mishima Michiaki
Published: February 2007

The concept of fractal geometry is useful for the analysis of irregular and complex structures often seen in nature. Here we apply this concept to investigate the structural mechanism of the development of pulmonary emphysema in the
klotho
mouse, which, after milk feeding, exhibits characteristics resembling aging and develops emphysema. We calculated the relationships between perimeter and size characterizing shape and between cumulative frequency and size of the terminal air spaces identified from histologic slides and found that both relations followed a power law with fractal properties. However, the fractal dimensions related to the shape and size (Dsn) in the
klotho
mice were significantly lower than in controls. Additionally, in the
klotho
mice, Dsn decreased with age without significant change in mean linear intercept. These abnormal morphological changes were restored when the
klotho
mice were fed with a vitamin D-deficient diet. Previously undescribed morphological model simulations showed that a random destruction, in which the destruction process occurs homogeneously in the lungs, was more consistent with the data than a correlated destruction that is usually seen in smoking-related human emphysema. These results suggest that the pathological changes in the lungs of the
klotho
mice are derived not from localized causes, but from systemic causes that are related to abnormal activation of vitamin D. The morphogenesis of emphysema in the
klotho
mice and morphological analyses using fractal geometry may contribute to the understanding of the progressive nature and cause of parenchymal destruction in human emphysema.
Long-distance combinatorial linkage between methylation and acetylation on histone H3 N termini
Authors: Taverna Sean D. , Ueberheide Beatrix M. , Liu Yifan , Tackett Alan J. , Diaz Robert L. , Shabanowitz Jeffrey , Chait Brian T. , Hunt Donald F. , Allis C. David
Published: February 2007

Individual posttranslational modifications (PTMs) on histones have well established roles in certain biological processes, notably transcriptional programming. Recent genomewide studies describe patterns of covalent modifications, such as H3 methylation and acetylation at promoters of specific target genes, or “bivalent domains,” in stem cells, suggestive of a possible combinatorial interplay between PTMs on the same histone. However, detection of long-range PTM associations is often problematic in antibody-based or traditional mass spectrometric-based analyses. Here, histone H3 from a ciliate model was analyzed as an enriched source of transcriptionally active chromatin. Using a recently developed mass spectrometric approach, combinatorial modification states on single, long N-terminal H3 fragments (residues 1–50) were determined. The entire modification status of intact N termini was obtained and indicated correlations between K4 methylation and H3 acetylation. In addition, K4 and K27 methylation were identified concurrently on one H3 species. This methodology is applicable to other histones and larger polypeptides and will likely be a valuable tool in understanding the roles of combinatorial patterns of PTMs.
Exchange protein activated by cAMP (Epac) mediates cAMP activation of p38 MAPK and modulation of Ca
2+
-dependent K
+
channels in cerebellar neurons
Authors: Ster Jeanne , De Bock Frédéric , Guérineau Nathalie C. , Janossy Andrea , Barrère-Lemaire Stéphanie , Bos Johannes L. , Bockaert Joël , Fagni Laurent
Published: February 2007

The exchange factor directly activated by cAMP (Epac) is a newly discovered direct target for cAMP and a guanine-nucleotide exchange factor for the small GTPase Rap. Little is known about the neuronal functions of Epac. Here we show that activation of Epac by specific cAMP analogs or by the pituitary adenylate cyclase-activating polypeptide induces a potent activation of the Ca
2+
-sensitive big K
+
channel, slight membrane hyperpolarization, and increased after-hyperpolarization in cultured cerebellar granule cells. These effects involve activation of Rap and p38 MAPK, which mobilizes intracellular Ca
2+
stores. These findings reveal a cAMP Epac-dependent and protein kinase A-independent signaling cascade that controls neuronal excitability.
Biological Pluralism and Homology
Authors: Jamniczky Heather A.
Published: February 2007

The study of similarity is fundamental to biological inquiry. Many homology concepts have been formulated that function successfully to explain similarity in their native domains, but fail to provide an overarching account applicable to variably interconnected and independent areas of biological research despite the monistic standpoint from which they originate. The use of multiple, explicitly articulated homology concepts, applicable at different levels of the biological hierarchy, allows a more thorough investigation of the nature of biological similarity. Responsible epistemological pluralism as advocated herein is generative of fruitful and innovative biological research, and is appropriate given the metaphysical pluralism that underpins all of biology.
Manipulation and the Causes of Evolution
Authors: Reisman Kenneth , Forber Patrick
Published: February 2007

Evolutionary processes such as natural selection and random drift are commonly regarded as causes of population-level change. We respond to a recent challenge that drift and selection are best understood as statistical trends, not causes. Our reply appeals to manipulation as a strategy for uncovering causal relations: if an appropriately controlled manipulation of variable A results in a systematic change in variable B, then A is a cause of B. We argue that selection and drift can be manipulated to produce different kinds of population-level change. They should therefore be regarded as causes.
Self-Induced Decoherence and the Classical Limit of Quantum Mechanics
Authors: Castagnino Mario , Lombardi Olimpia
Published: February 2007

In this paper we argue that the emergence of the classical world from the underlying quantum reality involves two elements: self-induced decoherence and macroscopicity. Self-induced decoherence does not require the openness of the system and its interaction with the environment: a single closed system can decohere when its Hamiltonian has continuous spectrum. We show that, if the system is macroscopic enough, after self-induced decoherence it can be described as an ensemble of classical distributions weighted by their corresponding probabilities. We also argue that classicality is an emergent property that arises when the behavior of the system is described from an observational perspective.
Anomalous Thermal Expansion of Chromium near TN
Authors: Bengt Stebler  , Claes-Göran Andersson  , Olof Kristensson
Published: February 2007

Strong lattice relaxation associated to the diffusion rate of interstitial nitrogen reported in an earlier paper was taken into account in a determination of the excess expansivity of single crystal chromium near the antiferromagnetic to paramagnetic transition. An anomalous positive expansivity peak just belowTNis thought of being the result of released magnetomechanical strain. The observations support the pinning model of antiferromagnetic domains.
Parallel tool industries in New Caledonian crows
Authors: Hunt Gavin R , Gray Russell D
Published: February 2007

Individual specialization in the use of foraging tools occurs in hunter–gatherer societies but is absent in non-human primate tool use. ‘Parallel tool industries’ in hunter–gatherers are mainly based on strict sexual division of labour that is highly reliant on social conformity. Here, we show that 12 individuals in a population of New Caledonian crows on Maré Island had strong preferences for either stick tools or pandanus tools. Eight of the 12 crows had exclusive preferences. The individual specialization that we found is probably associated with different foraging niches. However, in spite of sexual size dimorphism there was no significant association between the sex of crows and their tool preferences. Our findings demonstrate that highly organized, strict sexual division of labour is not a necessary prerequisite for the evolution of parallel tool industries.
Phylogenetic relationships and divergence times of Charadriiformes genera: multigene evidence for the Cretaceous origin of at least 14 clades of shorebirds
Authors: Baker Allan J , Pereira Sérgio L , Paton Tara A
Published: February 2007

Comparative study of character evolution in the shorebirds is presently limited because the phylogenetic placement of some enigmatic genera remains unclear. We therefore used Bayesian methods to obtain a well-supported phylogeny of 90 recognized genera using 5 kb of mitochondrial and nuclear sequences. The tree comprised three major clades: Lari (gulls, auks and allies plus buttonquails) as sister to Scolopaci (sandpipers, jacanas and allies), and in turn sister to Charadrii (plovers, oystercatchers and allies), as in previous molecular studies. Plovers and noddies were not recovered as monophyletic assemblages, and the Egyptian plover
Pluvianus
is apparently not a plover. Molecular dating using multiple fossil constraints suggests that the three suborders originated in the late Cretaceous between 79 and 102 Mya, and at least 14 lineages of modern shorebirds survived the mass extinction at the K/T boundary. Previous difficulties in determining the phylogenetic relationships of enigmatic taxa reflect the fact that they are well-differentiated relicts of old, genus-poor lineages. We refrain from suggesting systematic revisions for shorebirds at this time because gene trees may fail to recover the species tree when long branches are connected to deep, shorter branches, as is the case for some of the enigmatic taxa.
Species divergence in offspring begging intensity: difference in need or manipulation of parents?
Authors: Qvarnström Anna , Kehlenbeck Jenny Vogel , Wiley Chris , Svedin Nina , Sæther Stein Are
Published: February 2007

Conflicts over the delivery and sharing of food among family members are expected to lead to evolution of exaggerated offspring begging for food. Coevolution between offspring begging intensity and parent response depends on the genetic architecture of the traits involved. Given a genetic correlation between offspring begging intensity and parental response, there may be fast and arbitrary divergence in these behaviours between populations. However, there is limited knowledge about the genetic basis of offspring solicitation and parental response and whether these traits are genetically correlated. In this study, we performed a partial cross-fostering experiment of young between pied and collared flycatchers (Ficedula hypoleucaandFicedula albicollis) and recorded the behaviour of individual offspring and their (foster)parents. We found that nestling collared flycatchers reached a higher phenotypic quality, estimated both as mass at fledging and as intensity of their T-lymphocyte-mediated immune response when raised by heterospecific foster parents. However, although collared flycatchers begged relatively more intensively, we found no evidence of corresponding higher resistance (i.e. lower feeding rate) of adult collared flycatchers than of adult pied flycatchers. Thus, the difference in offspring begging intensity between the two species seems not to be a result of a difference in escalation of the parent–offspring conflict. Instead, the species' divergence in exaggeration of offspring begging intensity ‘honestly’ matches a difference between the species in offspring need. This interpretation is strengthened by the fact that the difference in begging intensity between the two species increased as the season progressed, coinciding with the higher sensitivity of nestling collared flycatchers to the seasonal decline in food availability. Thus, the behavioural differentiation appears to be a direct consequence of a life-history differentiation (offspring growth patterns).
Marine energy
Authors: Kerr David
Published: February 2007

Marine energy is renewable and carbon free and has the potential to make a significant contribution to energy supplies in the future. In the UK, tidal power barrages and wave energy could make the largest contribution, and tidal stream energy could make a smaller but still a useful contribution. This paper provides an overview of the current status and prospects for electrical generation from marine energy. It concludes that a realistic potential contribution to UK electricity supplies is approximately 80 TWh per year but that many years of development and investment will be required if this potential is to be realized.
Bone Metabolism and the Cardiometabolic Syndrome: Pathophysiologic Insights
Authors: McFarlane Samy I.
Published: February 2007

Accumulating evidence indicates that the several components of the cardiometabolic syndrome such as hypertension, increased triglycerides, and reduced high‐density lipoprotein cholesterol are also risk factors for low bone mineral density. Furthermore, some of the underlying risk factors for atherosclerosis in the cardiometabolic syndrome, such as inflammation, also play a major role in the pathogenesis of osteoporosis, the most common metabolic bone disease. In this article for the premiere issue of the Journal of the CardioMetabolic Syndrome, the author presents the current evidence of the interaction of bone metabolism and the cardiometabolic syndrome, highlighting the major research in this area and discussing the potential of therapeutic agents that will be useful in the treatment of osteoporosis as well as atherosclerosis.
Hypertension and the Cardiometabolic Syndrome—Is It the Blood Pressure Lowering or the Blood Pressure Medication That Is Important?
Authors: Ferdinand Keith C.
Published: February 2007

Perspectives of Hypertension in CMS focuses on the role hypertension plays in the metabolic syndrome. Keith C. Ferdinand, MD, Section Editor, welcomes submissions from clinicians and researchers of clinical commentaries, case studies, and medical images specifically related to hypertension and diabetes. For information on submissions for the column, see Information for Authors at www.lejacq.com.

Elevated blood pressure and the cardiometabolic syndrome are often difficult clinical challenges specifically related to fusing appropriate lifestyle modifications and antihypertensive agents. This case illustrates some of the factors clinicians have utilized in approaching patients with this common but challenging clinical situation.
The acute effects of exercise on cigarette cravings, withdrawal symptoms, affect and smoking behaviour: a systematic review
Authors: Taylor Adrian H. , Ussher Michael H. , Faulkner Guy
Published: February 2007

Aim  To review the effects of a single session of exercise on cigarette cravings, withdrawal symptoms and smoking behaviour.

Methods  A systematic search and critical appraisal of all 14 relevant studies.

Results  All 12 studies that compared a bout of exercise with a passive condition reported a positive effect on cigarette cravings, withdrawal symptoms and smoking behaviour. Two other studies that compared two intensities of exercise revealed no differences in outcomes. Single and multi‐item measures of cigarette cravings, withdrawal symptoms and negative affect decreased rapidly during exercise and remained reduced for up to 50 minutes after exercise. Effect sizes for seven studies that assessed ‘strength of desire to smoke’ showed a mean reduction, 10 minutes after exercise, of 1.1 (SD 0.9). Four studies reported a two‐ to threefold longer time to the next cigarette following exercise. Cravings and withdrawal symptoms were reduced with an exercise intensity from as high as 60–85% heart rate reserve (HRR) (lasting 30–40 minutes) to as low as 24% HRR (lasting 15 minutes), and also with isometric exercise (for 5 minutes). All but one study involved participants temporarily abstaining for the purposes of the experiment. Distraction was probably not the primary reason for the effects.

Conclusions  Relatively small doses of exercise should be recommended as an aid to managing cigarette cravings and withdrawal symptoms. Further research to understand the mechanisms involved, such as stress reduction or neurobiological mechanisms, could lead to development of more effective and practical methods to reduce withdrawal phenomena.
Ishihara plates on your handheld computer
Authors: Awad Z. , Natt R.S. , Pothier D.D.
Published: February 2007

Keypoints

• Testing for colour vision is important in assessing periorbital cellulitis and its complications.

• Electronic Ishihara colour plates are used effectively for this purpose.

• Portable LCD devices are widely available and most of us already have one.

• We use hand‐held computers to store and present the plates to the patient as a quick and readily available method of testing colour vision.
High transformation frequency of tobacco and rice via Agrobacterium‐mediated gene transfer by flanking a tobacco matrix attachment region
Authors: Zhang Meng‐Meng , Ji Lu‐Sha , Xue Hua , Yang Yu‐Tao , Wu Chang‐Ai , Zheng Cheng‐Chao
Published: February 2007

Nuclear matrix attachment regions (MARs) are suggested to regulate chromatin structure and influence the expression of flanking genes. Our previous study showed that TM2, a new DNA fragment isolated from tobacco, can bind with the rice nuclear matrix in vitro and increase transgene expression in vivo. Here, we investigated the role of TM2 MAR in improving transformation frequency of Agrobacterium‐mediated transformation in tobacco and rice. The gusA reporter gene flanked by TM2 MAR in pBI121 and pCAMBIA‐1301 vectors was controlled by a constitutive promoter or a photosynthetic tissue‐specific promoter. The presence of TM2 MAR in different expression cassettes significantly increased the numbers of kanamycin‐resistant tobacco shoots, hygromycin‐resistant rice calli and shoots. Seeds from the independent transgenic lines with TM2 MAR can germinate normally on the medium containing 500 mg l−1 kanamycin, whereas none of the seeds from the transgenic lines without TM2 MAR survived. Furthermore, RNA gel blot analysis revealed that nptII messenger RNA levels are more abundant in the independent transgenic lines with TM2 MAR than in the lines without TM2 MAR. Altogether, these data reveal a possible mechanism that TM2 MAR improves the transformation frequency by increasing nptII gene expression.
Multiple QTL‐effects of wheat Gpc‐B1 locus on grain protein and micronutrient concentrations
Authors: Distelfeld Assaf , Cakmak Ismail , Peleg Zvi , Ozturk Levent , Yazici Atilla M. , Budak Hikmet , Saranga Yehoshua , Fahima Tzion
Published: February 2007

Micronutrient malnutrition afflicts over three billion people worldwide and the numbers are continuously increasing. Developing genetically micronutrient‐enriched cereals, which are the predominant source of human dietary, is essential to alleviate malnutrition worldwide. Wheat chromosome 6B derived from wild emmer wheat [Triticum turgidum ssp. dicoccoides (Körn.) Thell] was previously reported to be associated with high Zn concentration in the grain. In the present study, recombinant chromosome substitution lines (RSLs), previously constructed for genetic and physical maps of Gpc‐B1 (a 250‐kb locus affecting grain protein concentration), were used to identify the effects of the Gpc‐B1 locus on grain micronutrient concentrations. RSLs carrying the Gpc‐B1 allele of T. dicoccoides accumulated on average 12% higher concentration of Zn, 18% higher concentration of Fe, 29% higher concentration of Mn and 38% higher concentration of protein in the grain as compared with RSLs carrying the allele from cultivated wheat (Triticum durum). Furthermore, the high grain Zn, Fe and Mn concentrations were consistently expressed in five different environments with an absence of genotype by environment interaction. The results obtained in the present study also confirmed the previously reported effect of the wild‐type allele of Gpc‐B1 on earlier senescence of flag leaves. We suggest that the Gpc‐B1 locus is involved in more efficient remobilization of protein, zinc, iron and manganese from leaves to the grains, in addition to its effect on earlier senescence of the green tissues.
Analysis of the Arabidopsis cell suspension phosphoproteome in response to short‐term low temperature and abscisic acid treatment
Authors: El‐Khatib Rami T. , Good Allen G. , Muench Douglas G.
Published: February 2007

To shed light on the early protein phosphorylation events involved in plant cell signaling in response to environmental stresses, we studied changes in the phosphorylation status of the Arabidopsis cell suspension proteome after short‐term low temperature and abscisic acid (ABA) treatment. We used radioactive pulse‐labeling of Arabidopsis cell suspension cultures and two‐dimensional (2‐D) gel electrophoresis to identify proteins that are differentially phosphorylated in response to these treatments. Changes in the phosphorylation levels of several proteins were detected in response to short‐term (5 min or less) cold (4°C) and chilling (12°C) stress and ABA treatment, and we observed that some of these changes were common between these treatments. In addition, we used Pro‐Q Diamond phosphoprotein gel stain to study the steady‐state protein phosphorylation status under the same treatments. We demonstrated that Pro‐Q Diamond effectively stained phosphorylated proteins, however, the overall Pro‐Q Diamond 2‐D gel staining pattern of proteins extracted from low‐temperature and ABA‐treated cells was not consistent with the gel patterns obtained by in vivo radioactive labeling of phosphoproteins. These in vivo pulsed‐labeling experiments demonstrate that the Arabidopsis phosphoproteome is dynamic in response to short‐term low temperature and ABA treatment, and thus represents a strategy for the identification of signaling proteins that could be utilized in the production of chilling or freeze tolerant crop varieties.
Therapeutic effect of nimesulide on colorectal carcinogenesis in experimental murine ulcerative colitis
Authors: Inoue Takuya , Murano Mitsuyuki , Abe Yosuke , Morita Eijiro , Murano Naoko , Yasumoto Shingo , Toshina Ken , Nishikawa Takashi , Maemura Kentaro , Hirata Ichiro , Katsu Ken‐ichi
Published: February 2007

Background:  Patients with ulcerative colitis (UC) exhibit an increased risk for the development of cancer of the colon and rectum. Cyclooxygenase (COX)‐2 inhibitors are known to suppress sporadic colorectal cancer, but it is unknown whether selective COX‐2 inhibitors exhibit a preventive effect in UC‐associated neoplasia. This study investigated the preventive effect of nimesulide, a selective COX‐2 inhibitor, on colorectal carcinogenesis in an experimental model of murine UC.

Methods:  Chronic colitis was induced in mice by administration of four cycles of dextran sulfate sodium (DSS) (each cycle: 5% DSS for 7 days and then distilled water for 14 days). The mice were killed 120 days after the completion of the fourth cycle. The mice were divided into the following five groups: group A served as a disease control; group B received a diet mixed with 400 p.p.m. of nimesulide during the whole period; group C received nimesulide during the four cycles of DSS administration (active phase); group D received nimesulide for 120 days from the end of the fourth cycle (remission phase); group E received no agents including DSS and served as a normal control.

Results:  The incidence of dysplasia and/or cancer was 28%, 15%, 11.8%, 6.7% and 0% in groups A–E, respectively. In group D, nimesulide significantly suppressed the occurrence of dysplasia and/or cancer (P < 0.05). Strong COX‐2 expression was detected by immunohistochemistry in cancer and dysplastic lesions while diffusely weak COX‐2 expression was also found in the residual colon (i.e. lesion‐free colon). The mucosal concentration of prostaglandin E2 was significantly lower in groups B and D than in group A.

Conclusions:  The administration of the selective COX‐2 inhibitor nimesulide (especially during the remission phase) exerts a suppressive effect on the development of dysplasia and/or cancer in a murine model of DSS‐induced colitis. These findings may have relevance to long‐standing UC in humans.
Risk factors for peritoneal dialysis‐related peritonitis: Can we reduce the incidence and improve patient selection?
Authors: KOTSANAS DESPINA , POLKINGHORNE KEVAN R , KORMAN TONY M , ATKINS ROBERT C , BROWN FIONA
Published: February 2007

Background:  Peritonitis is a serious complication of peritoneal dialysis (PD) and a major cause of hospitalization, catheter loss, transfer to haemodialysis and death. Thus, it is important to identify risk factors for PD‐related peritonitis in order to reduce the incidence and improve patient selection.

Methods:  This study is a prospective cohort review (1992–2003) with data consisting of 12 844 patient months, 506 PD patients and 623 episodes of peritonitis. Comorbidities and patient demographics were provided by the Australian and New Zealand Dialysis and Transplant Registry and these were merged with the hospital combined clinical and microbiology laboratory peritonitis database.

Results:  Variables identified to be associated with an increased likelihood of peritonitis were: age (every 10 years; OR, 1.26; 95% CI, 1.07–1.48), gender (female; OR, 1.91; 95% CI, 1.2–3.01), current smoker at entry to dialysis (OR, 1.71; 95% CI, 1.04–2.82) and the pre twin bag connection system (OR, 2.07; 95% CI, 1.22–3.52).

Conclusion:  Increasing age, female gender and smoking increased the risk of peritonitis. Identifying these risk factors will assist in the selection, training and monitoring of our PD population.
Use of magnetic resonance imaging to assess renal structure and function in reflux nephropathy
Authors: MCMAHON LAWRENCE P , KATSOULIS JOHN , TROUPIS JOHN M , BARIT DAVID , DELECHENEAU PHILIPPE
Published: February 2007

Aim:  Despite numerous potential advantages, the role of magnetic resonance imaging (MRI) in depicting structural and functional abnormalities in kidney disease has not been well addressed. In reflux nephropathy in particular, nuclear scintigraphy (NS) has become the diagnostic gold standard, however, other imaging modalities may be required for adequate clinical appraisal. We therefore assessed the use of MRI in reflux nephropathy, comparing findings with those obtained using conventional imaging techniques.

Methods:  Eight women with likely or proven reflux nephropathy underwent MRI scanning with structural and split functional appraisal. Results were compared with those obtained with ultrasound and NS.

Results:  As expected, structural abnormalities were better defined with MRI than with ultrasound. NS findings were confirmed in most, but not all, MRI scans: NS and ultrasound had failed to identify scarring and cyst development in one patient. A close correlation was observed between MRI and NS renal functional estimates, regardless of whether whole kidney (r2 = 0.87, P = 0001) or region of interest (r2 = 0.99, P < 0001) techniques were used. Bland Altman plot analysis suggested methods were interchangeable.

Conclusion:  MRI provided more accurate diagnostic information structurally than ultrasound and MRI and split renal functional estimates correlated well with NS. It achieved in one study what otherwise required additional scans and without the need for ionizing radiation. These results suggest it should be considered as a diagnostic tool for reflux nephropathy.
Small renal masses: the value of contrast‐enhanced colour Doppler imaging
Authors: Pallwein Leo , Mitterberger Michael , Aigner Friedrick , Pinggera Germar M. , Gradl Johann , Klauser Andrea , Halpern Ethan J. , Strasser Hannes , Bartsch Georg , Frauscher Ferdinand
Published: February 2007

OBJECTIVE

To assess the value of a microbubble‐based ultrasonographic contrast agent for enhancing blood vessels in colour Doppler imaging (CDI) of small renal masses.

PATIENTS AND METHODS

Fifty‐one patients with small renal masses (<3 cm in diameter) had prospective CDI before and after intravenous administration of the contrast agent Levovist® (Schering, Berlin, Germany). The degree of tumour vascularity was subjectively graded from 0 to IV (indicating an increasing vessel count). Furthermore, peak systolic velocity (PSV), resistive index, and pulsatility index were measured. The CDI findings were then compared with those obtained at histopathological examination.

RESULTS

Intra‐ and/or peritumoral vessels were detected in 26 lesions (51%) by unenhanced CDI and in 48 by enhanced CDI (94%; P = 0.006, McNemar test). Higher grades of tumour vascularity (grade III and IV) were more common in malignant renal masses (P < 0.01). There were PSVs of >80 cm/s only in malignant lesions. Based on receiver operating characteristic analysis, enhanced CDI (area under the curve 0.789) was more accurate than unenhanced CDI (0.576) for differentiating benign from malignant renal masses (P < 0.004).

CONCLUSION

Enhanced CDI is better than unenhanced CDI for detecting tumour vascularity, and for discriminating between benign and malignant small renal masses.
Multiplicity and complexity issues in contemporary production scheduling
Authors: Brauner N. , Crama Y. , Grigoriev A. , Van De Klundert J.
Published: February 2007

High multiplicity scheduling problems arise naturally in contemporary production settings where manufacturers combine economies of scale with high product variety. Despite their frequent occurrence in practice, the complexity of high multiplicity problems – as opposed to classical, single multiplicity problems – is in many cases not well understood. In this paper, we discuss various concepts and results that enable a better understanding of the nature and complexity of high multiplicity scheduling problems. The paper extends the framework presented in Brauneret al. [Journal of Combinatorial Optimization (2005) Vol. 9, pp. 313–323] for single machine, non‐preemptive high multiplicity scheduling problems, to more general classes of problems.
Political Influence and the Banking Sector: Evidence from Korea*
Authors: An Jaewook , Bae Sang‐Kun , Ratti Ronald A.
Published: February 2007

This paper uses panel data to compare the performance of Korean banks with and without effective government control of the appointment of chief operating officers. A privatization programme succeeded in spreading ownership of banks widely among the public, but government retention of an ownership stake in an institution meant de facto control by government. Despite charging lower loan rates, banks controlled by government experience higher bad loans ratios. This is in line with expectations of regulatory forbearance and government protection for recipients of political loans. Banks controlled by government are less efficient than privately controlled banks and bad loan variables are higher at banks with lower efficiency scores.
Cyclosporin in the treatment of patients with atopic eczema – a systematic review and meta‐analysis
Authors: Schmitt J , Schmitt N , Meurer M
Published: February 2007

Objective  To systematically assess the effectiveness of systemic cyclosporin in patients with severe atopic eczema.

Study design  Systematic review and meta‐analysis of controlled and uncontrolled trials. Electronic (MEDLINE, Cochrane databases) and hand search of published work. Independent standardized assessment of eligibility and data abstraction by two reviewers.

Methods  For the qualitative review data on study design, study population, methodology, results, tolerability and methodological quality was independently extracted by two reviewers. Qualitatively homogeneous studies were pooled using a random‐effects model. The mean relative change in objective disease severity was chosen as the main outcome measure for the quantitative analysis. Publication bias was explored by regressing treatment effect on sample size. Sensitivity analysis included meta‐regression of study‐specific covariates (inclusion of children, study type, concomitant topical therapy, study quality).

Results  Fifteen studies including 602 patients met the eligibility criteria. In all studies analysed, cyclosporin consistently decreased the severity of atopic eczema. Twelve studies appeared homogeneous enough to be pooled. After 2 weeks of treatment we found a dose‐related response with a pooled mean decrease in disease severity of 22% (95%‐CI 8–36%) under low‐dose cyclosporin ( 3 mg/kg) and 40% (95%‐CI 29–51%) at dosages  4 mg/kg. After 6–8 weeks the relative effectiveness was 55% (95%‐CI 48–62%).

Conclusions  Due to evidence of publication bias the quantitative results need to be interpreted with caution. Effectiveness of cyclosporin is similar in adults and children, but tolerability might be better in children. As data to adequately evaluate the long‐term effectiveness and safety of cyclosporin in patients with atopic eczema are unavailable, long‐term registries are encouraged.
Rapid Treatment of Tinea Nigra Palmaris With Ciclopirox Olamine Gel, 0.77%
Authors: Rosen Ted , Lingappan Ahila
Published: February 2007

A 48‐year‐old white woman presented with the abrupt onset of an asymptomatic but cosmetically distressing eruption on the palm. Physical examination disclosed a 2.5 × 2.0‐cm macular brown patch on the central left palm (Figure 1). Potassium hydroxide examination revealed brown‐pigmented, septate, branching filamentous hyphae. Clinical and microscopic findings were classic for tinea nigra palmaris. Medical, family, and social history were all unremarkable. The patient applied ciclopirox olamine gel, 0.77% b.i.d. for 3 days. Following this brief therapeutic intervention, the lesion resolved completely (Figure 2). She remained clear during the ensuing 14‐month follow‐up.

Pretreatment lesion

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Lesion following 3 days of ciclopirox 0.77% gel therapy

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Effects of Annealing Temperature on Microstructural Development at the Interface Between Zirconia and Titanium
Authors: Lin Kun‐Lin , Lin Chien‐Cheng
Published: February 2007

The interfacial reaction layers in the Ti/ZrO2 diffusion couples, isothermally annealed in argon at temperatures ranging from 1100° to 1550°C for 6 h, were characterized using scanning electron microscopy and transmission electron microscopy, both attached with an energy‐dispersive spectrometer. Very limited reaction occurred between Ti and ZrO2 at 1100°C. A β′‐Ti(Zr, O) layer and a two‐phase α‐Ti(O)+β′‐Ti(Zr, O) layer were found in the titanium side after annealing at T≥1300°C and T≥1400°C, respectively. A three‐phase layer, consisting of Ti2ZrO+α‐Ti(O, Zr)+β′‐Ti (O, Zr), was formed after annealing at 1550°C. In the zirconia side near the original interface, β′‐Ti coexisted with fine spherical c‐ZrO2−x, which dissolved a significant amount of Y2O3 in solid solution at T≥1300°C. Further into the ceramic side, the α‐Zr was formed due to the exsolution of Zr out of the metastable ZrO2−x after annealing at T≥1300°C: the α‐Zr was very fine and dense at 1300°C, continuously distributed along grain boundaries at 1400°C, and became coarsened at 1550°C. Zirconia grains grew significantly at T≥1400°C, with the lenticular t‐ZrO2−x being precipitated in c‐ZrO2−x. Finally, the microstructural development and diffusion paths in the Ti/ZrO2 diffusion couples annealed at various temperatures were also described with the aid of the Ti–Zr–O ternary phase diagram.
Human Genomic DNA Quantitation System, H‐Quant: Development and Validation for Use in Forensic Casework
Authors: Shewale Jaiprakash G. , Schneida Elaine , Wilson Jonathan , Walker Jerilyn A. , Batzer Mark A. , Sinha Sudhir K.
Published: February 2007

ABSTRACT: The human DNA quantification (H‐Quant) system, developed for use in human identification, enables quantitation of human genomic DNA in biological samples. The assay is based on real‐time amplification of AluYb8 insertions in hominoid primates. The relatively high copy number of subfamily‐specific Alu repeats in the human genome enables quantification of very small amounts of human DNA. The oligonucleotide primers present in H‐Quant are specific for human DNA and closely related great apes. During the real‐time PCR, the SYBR® Green I dye binds to the DNA that is synthesized by the human‐specific AluYb8 oligonucleotide primers. The fluorescence of the bound SYBR® Green I dye is measured at the end of each PCR cycle. The cycle at which the fluorescence crosses the chosen threshold correlates to the quantity of amplifiable DNA in that sample. The minimal sensitivity of the H‐Quant system is 7.6 pg/μL of human DNA. The amplicon generated in the H‐Quant assay is 216 bp, which is within the same range of the common amplifiable short tandem repeat (STR) amplicons. This size amplicon enables quantitation of amplifiable DNA as opposed to a quantitation of degraded or nonamplifiable DNA of smaller sizes. Development and validation studies were performed on the 7500 real‐time PCR system following the Quality Assurance Standards for Forensic DNA Testing Laboratories.
Prehypertension and the Cardiometabolic Syndrome: Is There Any Value in Pharmacologic Intervention?
Authors: Ferdinand Keith C.
Published: February 2007

The potential benefit of drug therapy for prehypertension and the cardiometabolic syndrome has previously not been confirmed. This case represents a patient who may show slowing or avoiding progression from prehypertension to hypertension based on recent trial evidence and assists the clinician in identifying the risk associated with blood pressure elevation before a conventional cut point of 140/90 mm Hg.
Perspectives on Prehypertension
Authors: Nesbitt Shawna D.
Published: February 2007

The Trial of Preventing Hypertension (TROPHY) investigated pharmacologic intervention in patients with prehypertension. TROPHY confirmed that treatment with candesartan 16 mg can prevent or postpone the development of hypertension, demonstrating a 66.3% reduction in hypertension incidence relative to placebo (26.8% absolute reduction) at 2 years, and a 15.6% reduction in hypertension incidence relative to placebo (9.8% absolute reduction) at 4 years. Further analyses of TROPHY may help to delineate the mechanisms behind this result more specifically, including those relating to components of the metabolic syndrome and markers of inflammation and early vascular change. The rate of progression and the concurrence of risk factors make a strong case for the development of a directive for closer follow‐up and treatment. The potential for success in reducing cardiovascular events is great, given the prevalence of prehypertension and the likelihood of progression.
Management of Hypertension in Children and Adolescents With the Metabolic Syndrome
Authors: Puri Mala , Flynn Joseph T.
Published: February 2007

Because elevated blood pressure is one of the defining criteria of the metabolic syndrome, treatment of hypertension will be required in many, if not most, children and adolescents diagnosed with the metabolic syndrome. This review highlights several aspects of the approach to treatment of hypertension in young patients with the metabolic syndrome, including the definition of hypertension, use of nonpharmacologic measures, indications for instituting antihypertensive medications, and the potential adjunctive role that insulin‐sensitizing agents may play in blood pressure reduction. The choice of antihypertensive agent is also discussed, along with consideration of the diabetogenic effects of various classes of antihypertensive agents. Consideration of all of these issues is important in achieving blood pressure control in children and adolescents with the metabolic syndrome, as appropriate treatment may help to forestall the development not only of type 2 diabetes but also of the cardiovascular disease that is frequently already present at the time of diagnosis of type 2 diabetes in adults.
Relationship Between the Cardiometabolic Syndrome and Obstructive Sleep Apnea
Authors: Schuster Steven R. , Tabba Maher , Sahota Pradeep
Published: February 2007

Obstructive sleep apnea (OSA), characterized by cessation of air flow for a minimum of 10 seconds despite continuous respiratory effort, is a prevalent condition in our society. Recent studies demonstrate that OSA is an independent risk factor for insulin resistance and the cardiometabolic syndrome. Hypoxemia and sleep fragmentation from OSA appear to produce autonomic activation, alterations in neuroendocrine function, and increased amounts of inflammatory cytokines (interleukin 6 and tumor necrosis factor α).These variables have important roles in the pathogenesis of insulin resistance and the cardiometabolic syndrome. It can be concluded that insulin sensitivity, a key contributor to the pathogenesis of the cardiometabolic syndrome, is mainly determined by the extent of obesity and, to a lesser extent, by OSA.The authors review OSA and summarize recent discoveries and proposed mechanisms of the causal relationship that OSA has with insulin resistance and the cardiometabolic syndrome independent of many confounding comorbidities.
JEG‐3 Cell Culture Supernatants Cause Reduced Interferon‐γ and Interleukin‐17 Production in Mixed‐Lymphocyte Reactions
Authors: Pongcharoen Sutatip , Niumsup Pannika R. , Sanguansermsri Donruedee
Published: February 2007

Problem

Immunoregulatory effects of choriocarcinoma‐derived factors on leukocytes have been documented. The present study was designed to investigate the effect of JEG‐3 culture supernatants on interferon‐γ (IFN‐γ), interleukin‐17 (IL‐17) and IL‐1β production in the mixed lymphocyte reactions (MLRs).

Method of study

A human choriocarcinoma cell line JEG‐3 was used to test the effects of its culture supernatants on the proliferation and cytokine production in the MLRs. The cell proliferation was assessed using the BrdU incorporation and the amounts of cytokines were measured using enzyme‐linked immunosorbent assays.

Results

The JEG‐3 culture supernatants caused significantly reduced IFN‐γ and IL‐17 production in the MLRs. However, the supernatants did not influence MLR production of IL‐1β.

Conclusion

IFN‐γ and IL‐17 are mainly produced by activated T cells but IL‐1β is primarily produced by monocytes, thus suggesting that immunoregulatory factors of JEG‐3 cells selectively inhibit cytokine production by activated T cells rather than that of the monocytes.