bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanisms of Transcription Activation Exerted by GadX and GadW at the
gadA
and
gadBC
Gene Promoters of the Glutamate-Based Acid Resistance System in
Escherichia coli
Authors: Tramonti Angela , De Canio Michele , Delany Isabel , Scarlato Vincenzo , De Biase Daniela
Published: November 2006

In
Escherichia coli
the
gad
system protects the cell from the extreme acid stress encountered during transit through the host stomach. The structural genes
gadA
,
gadB
, and
gadC
encode two glutamate decarboxylase isoforms and a glutamate/γ-aminobutyrate (GABA) antiporter, respectively. Glutamate decarboxylation involves both proton consumption and production of GABA, a neutral compound which is finally exported via the GadC antiporter. Regulation of
gadA
and
gadBC
transcription is very complex, involving several circuits controlling expression under different growth phase, medium, and pH conditions. In this study we found that the AraC-like activators GadX and GadW share the same 44-bp binding sites in the
gadA
and
gadBC
regulatory regions. The common binding sites are centered at 110.5 bp and 220.5 bp upstream of the transcriptional start points of the
gadA
and
gadBC
genes, respectively. At the
gadA
promoter this regulatory element overlaps one of the binding sites of the repressor H-NS. The DNA of the
gadBC
promoter has an intrinsic bend which is centered at position −121. These findings, combined with transcriptional regulation studies, may account for the two different mechanisms of transcriptional activation by GadX and GadW at the two promoters studied. We speculate that while at the
gadA
promoter GadX and GadW activate transcription by displacing H-NS via an antirepressor mechanism, at the
gadBC
promoter the mechanism of activation involves looping of the DNA sequence between the promoter and the activator binding site.
Development of Multiplex Real-Time Reverse Transcriptase PCR Assays for Detecting Eight Medically Important Flaviviruses in Mosquitoes
Authors: Chao Day-Yu , Davis Brent S. , Chang Gwong-Jen J.
Published: November 2006

A multiplex real-time reverse transcriptase PCR has been developed for the rapid detection and identification of eight medically important flaviviruses from laboratory-reared, virus-infected mosquito pools. The method used involves the gene-specific amplification of yellow fever virus (YFV), Japanese encephalitis virus (JEV), West Nile virus (WNV), St. Louis encephalitis virus (SLEV), and dengue virus (DENV) serotypes 1 to 4 (DENV-1 to DENV-4, respectively) by use of the flavivirus consensus amplimers located at the RNA-dependent RNA polymerase domain of nonstructural protein 5. Virus-specific amplicons were detected by four newly characterized TaqMan fluorogenic probes (probes specific for YFV, JEV, WNV, and SLEV) and four previously published probes specific for DENV-1 to -4 (L. J. Chien, T. L. Liao, P. Y. Shu, J. H. Huang, D. J. Gubler, and G. J. Chang, J. Clin. Microbiol. 44:1295-1304, 2006). This assay had a specificity of 100% and various sensitivities of at least 3.5 PFU/ml for YFV, 2.0 PFU/ml for JEV, 10.0 PFU/ml for WNV, and 10.0 PFU/ml for SLEV. Additionally, we have developed an in vitro transcription system to generate RNase-resistant RNA templates for each of these eight viruses. These templates can be incorporated into the assay as RNA copy number controls and/or as external controls for RNA-spiked mosquito pools for quality assurance purposes. Although further study with mosquitoes collected in the field is needed, the incorporation of this assay into mosquito surveillance could be used as an early-warning system for the detection of medically important flaviviruses, particularly when the cocirculation of multiple viruses in the same region is suspected.
Veillonella parvula
Discitis and Secondary Bacteremia: a Rare Infection Complicating Endoscopy and Colonoscopy?
Authors: Marriott D. , Stark D. , Harkness J.
Published: November 2006

We report a case of
Veillonella parvula
lumbar discitis and secondary bacteremia confirmed by molecular characterization of the 16S rRNA genes. Identification of the organism was essential for an appropriate choice of antimicrobial therapy following the failure of empirical flucloxacillin.
Veillonella
spp. are normal flora of the gastrointestinal tract, raising the possibility that an endoscopy and colonoscopy performed 8 weeks prior to presentation, during which small intestinal and rectal biopsies were obtained, was the portal of entry. This case highlights the importance of obtaining a microbiologic diagnosis, particularly in patients who previously have had procedures involving instrumentation.
Characterization of the Uracil-DNA Glycosylase Activity of Epstein-Barr Virus BKRF3 and Its Role in Lytic Viral DNA Replication
Authors: Lu Chih-Chung , Huang Ho-Ting , Wang Jiin-Tarng , Slupphaug Geir , Li Tsai-Kun , Wu Meng-Chuan , Chen Yi-Chun , Lee Chung-Pei , Chen Mei-Ru
Published: November 2006

Uracil-DNA glycosylases (UDGs) of the uracil-
N
-glycosylase (UNG) family are the primary DNA repair enzymes responsible for removal of inappropriate uracil from DNA. Recent studies further suggest that the nuclear human UNG2 and the UDGs of large DNA viruses may coordinate with their DNA polymerase accessory factors to enhance DNA replication. Based on its amino acid sequence, the putative UDG of Epstein-Barr virus (EBV), BKRF3, belongs to the UNG family of proteins, and it was demonstrated previously to enhance oriLyt-dependent DNA replication in a cotransfection replication assay. However, the expression and enzyme activity of EBV BKRF3 have not yet been characterized. In this study, His-BKRF3 was expressed in bacteria and purified for biochemical analysis. Similar to the case for the
Escherichia coli
and human UNG enzymes, His-BKRF3 excised uracil from single-stranded DNA more efficiently than from double-stranded DNA and was inhibited by the purified bacteriophage PBS1 inhibitor Ugi. In addition, BKRF3 was able to complement an
E. coli ung
mutant in rifampin and nalidixic acid resistance mutator assays. The expression kinetics and subcellular localization of BKRF3 products were detected in EBV-positive lymphoid and epithelial cells by using BKRF3-specific mouse antibodies. Expression of BKRF3 is regulated mainly by the immediate-early transcription activator Rta. The efficiency of EBV lytic DNA replication was slightly affected by BKRF3 small interfering RNA (siRNA), whereas cellular UNG2 siRNA or inhibition of cellular and viral UNG activities by expressing Ugi repressed EBV lytic DNA replication. Taking these results together, we demonstrate the UNG activity of BKRF3 in vitro and in vivo and suggest that UNGs may participate in DNA replication or repair and thereby promote efficient production of viral DNA.
Fcγ Receptors Play a Dominant Role in Protective Tumor Immunity against a Virus-Encoded Tumor-Specific Antigen in a Murine Model of Experimental Pulmonary Metastases
Authors: Lowe Devin B. , Shearer Michael H. , Jumper Cynthia A. , Bright Robert K. , Kennedy Ronald C.
Published: November 2006

Simian virus 40 (SV40) large tumor antigen (Tag) represents a virus-encoded tumor-specific antigen expressed in many types of human cancers and a potential immunologic target for antitumor responses. Fc receptors are important mediators in the regulation and execution of host effector mechanisms against conditions including infectious diseases, autoimmunity, and cancer. By examining tumor protection in SV40 Tag-immunized wild-type BALB/c mice using an experimental pulmonary metastasis model, we attempted to address whether engagement of the immunoglobulin G Fc receptors (FcγRs) on effector cells is necessary to mediate antitumor responses. All immunized BALB/c FcγR−/−knockout mice developed anti-SV40 Tag antibody responses prior to experimental challenge with a tumorigenic cell line expressing SV40 Tag. However, all mice deficient in the activating FcγRI (CD64) and FcγRIII (CD16) were unable to mount protective immunologic responses against tumor challenge and developed tumor lung foci. In contrast, mice lacking the inhibitory receptor FcγRII (CD32) demonstrated resistance to tumorigenesis. These results underscore the importance of effector cell populations expressing FcγRI/III within this murine tumor model system, and along with the production of a specific humoral immune response, antibody-dependent cell-mediated cytotoxicity (ADCC) may be a functioning mechanism of tumor clearance. Additionally, these data demonstrate the potential utility of ADCC as a viable approach for targeting vaccination strategies that promote FcγRI/III scavenging pathways against cancer.
Tumor Necrosis Factor (TNF) Protects Resistant C57BL/6 Mice against Herpes Simplex Virus-Induced Encephalitis Independently of Signaling via TNF Receptor 1 or 2
Authors: Lundberg Patric , Welander Paula V. , Edwards Carl K. , van Rooijen Nico , Cantin Edouard
Published: November 2006

Tumor necrosis factor (TNF) is a multifunctional cytokine that has a role in induction and regulation of host innate and adaptive immune responses. The importance of TNF antiviral mechanisms is reflected by the diverse strategies adopted by different viruses, particularly members of the herpesvirus family, to block TNF responses. TNF binds and signals through two receptors,Tnfrsf1a(TNF receptor 1 [TNFR1], or p55) andTnfrsf1b(TNFR2, or p75). We report here that herpes simplex virus 1 (HSV-1) infection of TNF−/−mice on the resistant C57BL/6 genetic background results in significantly increased susceptibility (P< 0.0001, log rank test) to fatal HSV encephalitis (HSE) and prolonged persistence of elevated levels of virus in neural tissues. In contrast, although virus titers in neural tissues of p55−/−N13 mice were elevated to levels comparable to what was found for the TNF−/−mice, the p55−/−N13 mice were as resistant as control C57BL/6 mice (P> 0.05). The incidence of fatal HSE was significantly increased by in vivo neutralization of TNF using soluble TNFR1 (sTNFR1) or depletion of macrophages in C57BL/6 mice (P= 0.0038 andP= 0.0071, respectively). Strikingly, in vivo neutralization of TNF in HSV-1-infected p55−/−p75−/−mice by use of three independent approaches (treatment with soluble p55 receptor, anti-TNF monoclonal antibody, or in vivo small interfering RNA against TNF) resulted in significantly increased mortality rates (P= 0.005), comparable in magnitude to those for C57BL/6 mice treated with sTNFR1 (P= 0.0018). Overall, these results indicate that while TNF is required for resistance to fatal HSE, both p55 and p75 receptors are dispensable. Precisely how TNF mediates protection against HSV-1 mortality in p55−/−p75−/−mice remains to be determined.
Beneficial effects of isometric strength training on endothelial dysfunction in rats
Authors: Figard Hélène , Gaume Vincent , Mougin Fabienne , Demougeot Céline , Berthelot Alain
Published: November 2006

Using female 4-week-old Sprague–Dawley rats, we investigated the effects of 14 weeks of progressive strength isometric training on endothelium dysfunction after estrogen deficiency. We also proposed possible mechanism(s) by which such training acted on endothelium-dependent vasodilation in thoracic aortic rings. Rats were randomly divided into 4 groups of 8 rats: a sham operated group, an ovariectomized sedentary group receiving 17β-estradiol vehicle s.c. daily, an ovariectomized sedentary group receiving a daily injection of 20 µg·kg–1 17β-estradiol s.c., and an ovariectomized exercised group receiving daily s.c. vehicle. Vascular reactivity of aortic rings have been evaluated by a cumulative dose of acetylcholine (ACh), in the presence or absence of l-NAME (N-nitro-l-arginine methyl ester), indomethacin, thapsigargin, iberiotoxin, apamin, and tetraethylammonium. Ovariectomy markedly decreased the relaxation caused by ACh, whereas 17β-estradiol treatment induced a significant increase in the relaxation elicited by ACh. Isometric exercise enhanced relaxation due to ACh. This enhancement was attenuated in the presence of l-NAME, indomethacin, thapsigargin, iberiotoxin, and apamin. Our data indicated, for the first time, that the endothelium-dependent relaxant response to ACh was markedly improved in trained ovariectomized rats. This increased vasodilation is mediated by nitric oxide, cyclooxygenase, sarco-endoplasmic reticulum Ca2+-ATPase pathways, and endothelium-derived hyperpolarizing factor. Finally, this study suggested that resistance training may provide benefits in addressing vascular dysfunction consequent to a decline in estrogen levels after menopause. However, any benefits for age-related vascular dysfunction remain to be demonstrated.
Rhizobium giardinii is the microsymbiont of Illinois bundleflower (Desmanthus illinoensis (Michx.) Macmillan) in midwestern prairies
Authors: Beyhaut Elena , Tlusty Becki , van Berkum Peter , Graham Peter H
Published: November 2006

Illinois bundleflower (Desmanthus illinoensis (Michx.) Macmillan) has potential as a grain and forage legume for the American Midwest. Inoculant-quality rhizobia for this legume have been identified but not previously characterized. Rhizobia trapped from 20 soils in the natural range of the Illinois bundleflower had characteristics that placed them overwhelmingly within the species Rhizobium giardinii, one of the few occasions this species has been recovered from legumes, raising questions on the biogeography and spread of midwestern prairie rhizobia.Key words: Rhizobium taxonomy, biogeography, diversity, prairie legumes.
Heme oxygenase activity in fetal and adult sheep is not altered by acclimatization to high altitude hypoxia
Authors: Kinobe Robert T. , Vlahakis Jason Z. , Soong Jonathan M. , Szarek Walter A. , Brien James F. , Longo Lawrence D. , Nakatsu Kanji
Published: November 2006

Hypoxic stress has been reported to induce the expression of stress proteins such as heme oxygenase (HO), which catalyze the breakdown of heme to generate biliverdin, ferrous iron, and carbon monoxide. These degradation products play a role in the regulation of a variety of processes such as vascular tone, inflammation, and central nervous system function. In mammals, there are 2 catalytically functional HO isozymes, HO-1 (inducible) and HO-2 (constitutive). HO-1 expression is regulated by an array of nonphysiological and physiological stimuli including acute hypoxemia. As relatively little is known of the HO response to prolonged hypoxia in whole animals other than small laboratory rodents, the aim of this work was to examine the effect of long-term hypoxia on total HO activity in fetal and adult ovine tissue. Sheep were maintained at high altitude (3820 m), after which the following tissues were harvested from near-term fetal and non-pregnant ewes for in vitro measurement of HO activity: left ventricle, renal papilla, lung apex, pulmonary artery, carotid artery, mesenteric artery, placental cotyledon, spleen, and brain frontal cortex. There were no significant differences between HO activities in tissues from hypoxic fetal and adult sheep compared with their normoxic controls. Fetal heart HO activities were higher than those of adult tissue (p < 0.05), whereas adult spleen HO activity was significantly higher than that of fetal tissue (p < 0.05). In conclusion, these data indicate that long-term exposure to high altitude hypoxia does not have a persistent effect on HO activity in ovine tissues. Also, except for the spleen where there is a high expression of HO-1 under normal conditions, tissue HO activity is correlated with the expression of HO-2, the constitutive isozyme.
Feather mites are positively associated with daily survival in cliff swallows
Authors: Brown Charles R. , Brazeal Kathleen R. , Strickler Stephanie A. , Brown Mary Bomberger
Published: November 2006

Feather mites (Acari: Astigmata) have been reported to be parasitic, commensal, and even mutualistic on the birds that serve as their hosts. We investigated whether there was a relationship between number of feather mites ( Pteronyssoides obscurus (Berlese, 1885)) on the wing and daily survival of cliff swallows ( Petrochelidon pyrrhonota (Vieillot, 1817)) during the breeding season at 12 nesting colonies in Nebraska in 2005. Survival of birds with known mite loads was monitored by mark–recapture, and survival models with and without a linear effect of mites were compared with the program MARK. For adult swallows, mites were positively associated with daily survival at six colonies, negatively associated at two colonies, and there was no relationship at four colonies. For recently fledged juveniles studied at two colonies, survival varied positively with mite load at one, while the other showed no relationship. Feather mites may provide direct benefits to cliff swallows by consuming old oil, pollen, fungi, and harmful bacteria on the feathers or by pre-empting resources used by deleterious fungi or bacteria. The data do not support a truly parasitic relationship in which mites are costly to cliff swallows; these particular feather mites may be beneficial mutualists.
Scanning electron microscope study of the development of mandibular structure and the molar surface morphology ofBranchinella maduraiensisandStreptocephalus dichotomus(Crustacea, Anostraca)
Authors: Velu Chinavenmeni S. , Munuswamy Natesan
Published: November 2006

In the present study, the molar surface morphology of Streptocephalus dichotomus Baird, 1860 and Branchinella maduraiensis Raj, 1961 is analyzed and correlated with the distribution of these species in ephemeral pools. The larval stages of S. dichotomus are characterized by scanning electron microscopy in relation to their feeding physiology, which shows their morphological complexity during developmental stages. The larval mandible consists of a coxa with a three-segmented palp, and further development leads to its gradual transition into the adult mandible. Muscles involved in mandibular movement exhibit rotatory and counter-rotatory movement, which enhances the grinding of food materials. Analysis of the molar surface morphology of B. maduraiensis and S. dichotomus reveals that the mandibles are asymmetrical. Detailed analysis of the topography of the molar illustrates specific structural differences between the species. Gut content analysis also perfectly matches the molar morphology of these species, confirming that B. maduraiensis handles zooplankton more preferentially than S. dichotomus. Our investigation of these fairy shrimps provides information on their molar surface morphology and feeding biology, which increases the understanding of their coexistence.
Decreased baroreflex sensitivity in acute schizophrenia
Authors: Bär Karl-Jürgen , Boettger Michael Karl , Berger Sandy , Baier Vico , Sauer Heinrich , Yeragani Vikram K. , Voss Andreas
Published: November 2006

Decreased vagal activity has been described in acute schizophrenia and might be associated with altered cardiovascular regulation and increased cardiac mortality. The aim of this study was to assess baroreflex sensitivity in the context of psychopathology. Twenty-one acute, psychotic, unmedicated patients with a diagnosis of paranoid schizophrenia were investigated after admission to the hospital. Results were compared with 21 healthy volunteers matched with respect to age and sex. Cardiovascular parameters obtained included measures for heart rate variability, baroreflex sensitivity, as well as cardiac output, left ventricular work index, and total peripheral resistance. All parameters investigated were analyzed using linear and novel nonlinear techniques. Positive and negative symptoms were assessed to estimate the impact of psychopathology on autonomic parameters. Subjects with acute schizophrenia showed reduction of baroreflex sensitivity accompanied by tachycardia and greatly increased left ventricular work index. Nonlinear parameters of baroreflex sensitivity correlated with positive symptoms. For heart rate variability, mainly parameters indicating parasympathetic modulation were decreased. Vascular pathology could be excluded as a confounding factor. These results reflect a dysfunctional cardiovascular regulation in acute schizophrenic patients at rest. The changes are similar to adaptational regulatory processes following stressful mental or physical tasks in healthy subjects. This study suggests that hyperarousal in acute schizophrenia is accompanied by decreased efferent vagal activity, thus increasing the risk for cardiovascular mortality. Future studies are warranted to examine the role of the sympathetic system and possible autonomic differences in hyperarousal induced by anxiety and/or external stressful events.
Template-Based Spike Pattern Identification With Linear Convolution and Dynamic Time Warping
Authors: Chi Zhiyi , Wu Wei , Haga Zach , Hatsopoulos Nicholas G. , Margoliash Daniel
Published: November 2006

Pattern identification for spiking activity, which is central to neurophysiological analysis, is complicated by variability in spiking at multiple timescales. Incorporating likelihood tests on the variability at two timescales, we developed an approach to identifying segments from continuous neurophysiological recordings that match preselected spike “templates.” At smaller timescales, each component of the preselected pattern is represented by a linear filter. Local scores to measure the similarities between short data segments and the pattern components are computed as filter responses. At larger timescales, overall scores to measure the similarities between relatively long data segments and the entire pattern are computed by dynamic time warping, which combines the local similarity scores associated with the pattern components, optimizing over a range of intercomponent time intervals. Occurrences of the pattern are identified by local peaks in the overall similarity scores. This approach is developed for point process representations and binary representations of spiking activity, both deriving from a single underlying statistical model. Point process representations are suitable for highly reliable single-unit responses, whereas binary representations are preferred for more variable single-unit responses and multiunit responses. Testing with single units recorded from individual electrodes within the robust nucleus of the arcopallium of zebra finches and with recordings from an array placed within the motor cortex of macaque monkeys demonstrates that the approach can identify occurrences of specified patterns with good time precision in a broad range of neurophysiological data.
Developmental Changes in Retrograde Messengers Involved in Depolarization-Induced Suppression of Excitation at Parallel Fiber-Purkinje Cell Synapses in Rodents
Authors: Crepel Francis
Published: November 2006

At parallel fiber (PF) to Purkinje cell (PC) synapses, depolarization-induced suppression of excitation (DSE) and suppression of PF-excitatory postsynaptic currents (EPSCs) by activation of postsynaptic mGluR1 glutamate (Glu) receptors involve retrograde release of endocannabinoids. However, Levenes et al. suggested instead that Glu was the retrograde messenger in this latter case. Because the study by Levenes et al. was performed in nearly mature rats, whereas most others were performed in juvenile animals, DSE was re-investigated in juvenile versus nearly mature rats and mice. Indeed, DSE was preferred here to agonist-induced suppression of PF-EPSCs, to avoid possible indirect effects in this latter case. In 10- to 12-day-old rats, DSE of PF-EPSCs was entirely mediated through retrograde release of endocannabinoids. In 18- to 22-day-old-rats, DSE was partly resistant to CB1 cannabinoid receptor antagonists. The remaining component was potentiated by the Glu uptake inhibitor d-threo-beta-benzyloxyaspartate (d-TBOA) and blocked by the desensitizing kainate (KA) receptor agonist (2S,4R)-4-methylglutamic acid (SYM 2081). This SYM-2081-sensitive component of DSE was accompanied by a paired-pulse facilitation increase that was also potentiated by d-TBOA and blocked by SYM 2081. In nearly mature wild-type and GluR6 −/− mice, results fully confirmed the presence of an endocannabinoid-independent component of DSE that involves retrograde release of Glu and activation of presynaptic KA receptors including GluR6 receptor subunits. Therefore retrograde release of Glu by PCs participates to DSE at PF-PC synapses in nearly mature rodents but not in juvenile ones, and Glu probably operates through activation of presynaptic KA receptors that include GluR6 receptor subunits.
Random fixed points of multivalued inward random operators
Authors: Khan A. R. , Domlo A. A.
Published: November 2006

The purpose of this paper is to provide a substantial improvement and random analogues of several results due to Benavides and Ramírez (2004). Our work sets random versions of the results of Shahzad and Lone (2005) and improves the work of Plubtieng and Kumam (2006).
The Adipose Renin‐Angiotensin System Modulates Systemic Markers of Insulin Sensitivity and Activates the Intrarenal Renin‐Angiotensin System
Authors: Kim Suyeon , Soltani-Bejnood Morvarid , Quignard-Boulange Annie , Massiera Florence , Teboul Michele , Ailhaud Gerard , Kim Jung Han , Moustaid-Moussa Naima , Voy Brynn H.
Published: November 2006

Background. The adipose tissue renin‐angiotensin system (RAS) contributes to regulation of fat mass and may also impact systemic functions such as blood pressure and metabolism.Methods and results. A panel of mouse models including mice lacking angiotensinogen,Agt(Agt‐KO), mice expressingAgtsolely in adipose tissue (aP2‐Agt/Agt‐KO), and mice overexpressingAgtin adipose tissue (aP2‐Agt) was studied. Total body weight, epididymal fat pad weight, and circulating levels of leptin, insulin, and resistin were significantly decreased inAgt‐KO mice, while plasma adiponectin levels were increased. aP2‐Agtmice exhibited increased adiposity and plasma leptin and insulin levels compared to wild type (WT) controls. Angiotensinogen and type I Ang II receptor protein levels were also elevated in kidney of aP2‐Agtmice.Conclusion. These findings demonstrate that alterations in adipose RAS activity significantly impact both local and systemic physiology in a way that may contribute to the detrimental health effects of obesity.
Soluble CD40 Ligand Levels in Otherwise Healthy Subjects With Impaired Fasting Glucose
Authors: Tasci Ilker , Dogru Teoman , Sonmez Alper , Genc Halil , Kilic Selim , Olgun Abdullah , Gok Mahmut , Erdem Gokhan , Erikci Selahattin
Published: November 2006

Unlike diabetes mellitus and impaired glucose tolerance, it is not clear whether the subjects with impaired fasting glucose (IFG) are at increased risk of atherosclerosis and cardiovascular diseases. The CD40‐CD40 ligand interaction is involved in the mechanism of atherosclerosis. We investigated whether soluble CD40L (sCD40L) as well as high sensitive C‐reactive protein (hsCRP) levels are increased in subjects with IFG having no confounding factors for inflammation or atherosclerosis. Twenty four IFG subjects with no additional disorders and 40 appropriate healthy controls were studied. sCD40L and hsCRP levels in the IFG and control groups were similar. Blood pressures, total and LDL‐cholesterol, and triglyceride levels were also similar, whereas HDL‐cholesterol was lower and HOMA‐IR indexes were higher in the IFG group. Though the sample size was small, the present data show that sCD40L seems not to alter in subjects with IFG suggesting that it might not be an independent risk factor for atherosclerosis.
Diabetes, TZDs, and Bone: A Review of the Clinical Evidence
Authors: Schwartz Ann V.
Published: November 2006

Evidence from rodent and in vitro models suggests that activation of PPAR-γby thiazolidinediones (TZDs) causes increased bone marrow adiposity and decreased osteoblastogenesis, resulting in bone loss. TZDs are prescribed for the treatment of diabetes, providing an opportunity to determine whether PPAR-γactivation also impacts bone in humans. In addition, since type 2 diabetes is associated with higher fracture risk, an understanding of the clinical impact of TZDs on bone is needed to guide fracture prevention efforts in this population. This review summarizes current findings regarding type 2 diabetes and increased fracture risk and then considers the available evidence regarding TZD use and bone metabolism in humans.
Reversal of Drug Resistance in Breast Cancer Cells by Transglutaminase 2 Inhibition and Nuclear Factor-κB Inactivation
Authors: Kim Dae-Seok , Park Sung-Soo , Nam Byung-Ho , Kim In-Hoo , Kim Soo-Youl
Published: November 2006

Induction of transglutaminase 2 (TGase 2) by epidermal growth factor (EGF) in human breast cancer cells increases their oncogenic potential and chemoresistance. The role of TGase 2 in the development of these tumor-related phenotypes remains to be elucidated, but it has been shown that expression of a dominant-negative form of TGase 2 reverses EGF-mediated chemoresistance in breast cancer cells. We examined several different breast cancer cell lines, representing both EGF receptor (EGFR)-positive and EGFR-negative breast cancers, and found that doxorubicin-resistant cells had a higher level of TGase 2 compared with doxorubicin-sensitive cells independent of the EGFR expression level. TGase 2 inhibition increased the chemosensitivity of drug-resistant cells, concomitant with a decrease in nuclear factor-κB (NF-κB) activity. Increasing the level of TGase 2 in drug-sensitive cells by transient transfection reduced the level of inhibitory subunit α of NF-κB (IκBα) and increased NF-κB activity in these cells. Inhibition of TGase 2 in drug-resistant cells by RNA interference increased the levels of IκBα, and this correlated with a shift in the accumulation of NF-κB from the nucleus to the cytosol. We recently showed that TGase 2 activated NF-κB through polymerization and depletion of free IκBα during inflammation. Therefore, increased expression of TGase 2 and subsequent activation of NF-κB may contribute to drug resistance in breast cancer cells independently of EGF signaling. (Cancer Res 2006; 66(22): 10936-43)
TMPRSS2:ERG Fusion by Translocation or Interstitial Deletion Is Highly Relevant in Androgen-Dependent Prostate Cancer, But Is Bypassed in Late-Stage Androgen Receptor–Negative Prostate Cancer
Authors: Hermans Karin G. , van Marion Ronald , van Dekken Herman , Jenster Guido , van Weerden Wytske M. , Trapman Jan
Published: November 2006

Recently, a unique fusion between the prostate-specific, androgen-regulated TMPRSS2 gene and the ETS genes ERG, ETV1, or ETV4 has been described in clinical prostate cancer. We investigated mechanisms of expression of four ETS genes, ERG, ETV1, ETV4, and FLI1, in 11 xenografts representing different stages of prostate cancer. All five androgen-dependent xenografts showed as major transcript overexpression of two splice variants of TMPRSS2:ERG, linking TMPRSS2 exon 1 or 2 sequences to ERG exon 4. In one of two androgen-sensitive xenografts, fusion transcripts of TMPRSS2 and ETV1 were detected. Array-based comparative genomic hybridization and interphase fluorescence in situ hybridization indicated both interstitial deletions and translocations as mechanisms of TMPRSS2:ERG gene fusion. Importantly, TMPRSS2 to ERG fusions were also observed in three of four androgen-independent, androgen receptor (AR)–negative xenografts and in two AR-negative clinical prostate cancer specimens; however, the fusion gene was not expressed. In almost all AR-negative tumor samples, overexpression of wild-type ETV4 or FLI1 was detected. Combined, our observations indicate a key role of fusion of TMPRSS2 and ETS genes in most androgen-regulated prostate cancers, which might be bypassed by androgen-independent expression of wild-type ETS factors in late-stage disease. (Cancer Res 2006; 66(22): 10658-63)
Oncogenes, Trousseau Syndrome, and Cancer-Related Changes in the Coagulome of Mice and Humans
Authors: Rak Janusz , Yu Joanne L. , Luyendyk James , Mackman Nigel
Published: November 2006

Cancer is often associated with venous thrombosis, a phenomenon that was first described by Trousseau in 1865 (Trousseau syndrome). Recent studies have begun to explain how oncogenic events may deregulate the hemostatic system. For instance, activated oncogenes (K-ras, EGFR, PML-RARα, and MET) or inactivated tumor suppressors (e.g., 53 or PTEN) may increase the risk of thrombosis by inducing the expression of tissue factor, a potent procoagulant molecule, and plasminogen activator inhibitor-1, a fibrinolysis inhibitor. In a more complex clinical reality, transforming genes may often act in concert with numerous epigenetic factors, including hypoxia, inflammation, anticancer therapy, contact between blood and metastatic cancer cells, and emission of procoagulant vesicles from tumors and their stroma into the circulation. To add to mechanistic insights gained from mouse models, which may not fully phenocopy human Trousseau syndrome, we suggest that valuable clues to progression and thrombosis risk may be obtained by monitoring multiple hemostatic variables in cancer patients (“coagulomics”). (Cancer Res 2006; 66(22): 10643-6)
Comparative Morphology of the Avian Cerebellum: II. Size of Folia
Authors: Iwaniuk Andrew N. , Hurd Peter L. , Wylie Douglas R.W.
Published: November 2006

Despite the highly conserved circuitry of the cerebellum, its overall shape varies significantly among and within vertebrate classes. In birds, one of the most prominent differences among orders is the relative size of the cerebellar folia. The enlargement/reduction of individual folia is thought to relate to specific behavioral differences among taxa, but this has not been adequately tested. Here, we survey variation in cerebellar folia size among 96 species of birds and test for phylogenetic effects and correlations with behavior using a combination of conventional and phylogeny-based statistics. Overall, we found that phylogenetic history accounts for a significant amount of variation in the relative size of individual folia. Order membership, in particular, accounted for more than half of the interspecific variation in folia size. There are also complex relationships among folia such that the expansion of one folium is often accompanied by a reduction in other folia. With respect to behavioral correlates: (1) we did not find any significant correlations between folia size and reliance on trigeminal input; (2) there was some evidence supporting a correlation between strong hindlimbs and an expansion of the anterior lobe; and (3) there were significant reductions in folia I–III and expansions in folia VI and VII in species classified as strong fliers. This expansion likely reflects increased visual processing requirements in species with rapid and/or agile flight. It therefore appears that folium size is a product of both phylogenetic history and behavior in birds.
Evolving Combinatorial Problem Instances That Are Difficult to Solve
Authors: van Hemert Jano I.
Published: November 2006

This paper demonstrates how evolutionary computation can be used to acquire difficult to solve combinatorial problem instances. As a result of this technique, the corresponding algorithms used to solve these instances are stress-tested. The technique is applied in three important domains of combinatorial optimisation, binary constraint satisfaction, Boolean satisfiability, and the travelling salesman problem. The problem instances acquired through this technique are more difficult than the ones found in popular benchmarks. In this paper, these evolved instances are analysed with the aim to explain their difficulty in terms of structural properties, thereby exposing the weaknesses of corresponding algorithms.
Inquiring Into Writing
Authors: Gale Ken , Wyatt Jonathan
Published: November 2006

This article is a transcript of an interview that the authors conducted via e-mail during a 3-month period in early 2005. The interview explores their experience of writing and came to life because the authors had been struck, in exchanging work with each other during their doctoral studies, by significant differences in their writing styles. The focus of the interview became the actual process of writing and its meanings to the authors, how writing both reflects and creates their selves. The authors also sought to explore the interview process itself. Framing theirs as a postmodern interview, the authors aim to collaborate, to blur the boundaries between interviewer and interviewee, and to consider the roles of narrator, interviewer, and outsider witness that they took during the process.
Who Is Better Than Whom? Two Tales From Melting Pot Boils Over
Authors: Athens Lonnie
Published: November 2006

Two tales about confrontations between Whites from different ethnic back-grounds that took place in Virginia during the twilight of the Jim Crow era are told here. In both tales, Pete Aegean, whose parents are Greek immigrants and who works as a counterman in a Greek-immigrant-owned café, gets into conflicts with the patrons who are White native Southerners. The conflicts turn violent after they trade ethnic slurs. Although Pete emerges as the victor, it creates a serious dilemma for him. On one hand, he maintains his pride and gains the begrudging respect of the White mill hands who patronize the café. On the other hand, Pop, the café's owner, fires Pete for placing his false sense of ethnic pride above their mutual economic interests. Pete's firing raises the question of what is the right and wrong way for immigrants and their offspring to win the respect and admiration of their host country's native inhabitants.
Heteronarrative Analysis
Authors: Kaufmann Jodi
Published: November 2006

In this article, the author discusses a method of narrative analysis that may function to expand the heteronormative, the ideology that heterosexuality and traditional gender and sex roles are natural, normal, and morally superior. Heteronarrative analysis examines how the body and subject are made up within the heteronormative through the structure of narrative. Prior to discussing this method, the author will review the theories that inform it—the body and subject formed in and through language, the heteronarrative and the constitution of the body and subject, and narratology, a popular narrative theory from literary studies. The author concludes with a few thoughts on the possibilities of expanding the heteronormative through heteronarrative analysis.
The “Eddie Scissons Syndrome” and Fictionalized Public Confessionals
Authors: Rinehart Robert E.
Published: November 2006

The “Eddie Scissons Syndrome,” a term coined by fiction writer W. P. Kinsella, describes a phenomenon wherein people exaggerate their personal histories for their own personal gain. In this article, the phenomenon is first explored in two ways: as a trope in which fiction writers demonstrate and advance character, and as an object of academic discourse, primarily through the work of Crepeau and Scheinkopf. Furthermore, the Eddie Scissons Syndrome phenomenon is used to explore some current public exaggerations, in particular the United States' governmental justification for a preemptive strike on Iraq, and to advance concerns about both private and public truth claims.
Un/masking Identity
Authors: Rodriguez Dalia
Published: November 2006

Using personal narrative, this article examines how masks function to subordinate African American and Latina women in the academy. The article uses Critical Race Theory and more specifically critical race gendered epistemologies, including Black feminist thought and Chicana feminist epistemology, to understand how females of color resist in the academy. Interweaving two narratives, the narrative of an African American woman and her experiences in the White academy with the author's personal narrative about resisting cultural and linguistic domination, this article seeks to understand the process of redefinition leading toward self empowerment. Critical in exposing hidden truths, the article unmasks racism in the White academy, challenging the dominant discourse.
The New Principal
Authors: McDonald Jane A.
Published: November 2006

This case focuses on some of the considerations and activities involved in human resource management that confront a principal at the beginning of the school year. The principal, who was an assistant principal in a neighboring district last year, is faced with a number of questions and unfamiliar procedures that accompany the new work context. By identifying and addressing the challenges faced by this novice principal, aspiring educational leaders can model her skills in prioritizing, communicating, and strategically implementing human resource responsibilities in a school setting.
And the Band Played on? Social Justice and the Wilson Middle School Arts Program
Authors: Karpinski Carol F.
Published: November 2006

Effecting change for educational equity is challenging for school administrators. This case study focuses on a new principal with a social justice perspective who recognizes that changes in student demographics require a reassessment of school programs. Realizing that gross inequities have become institutionalized at the school regarding student placement in courses in the arts program, the principal is also concerned that this imbalance may have spilled over into other aspects of school life and instruction. Change will require confronting inequities and adjusting attitudes, procedures, and instruction.
Etude cinétique de l'attaque acide de la sépiolite: modifications des propriétés texturales
Authors: Corma A. , Mifsud A. , Pérez J.
Published: November 2006

Resume

Dans ce travail on a étudié l'influence des conditions expérimentales du traitement acide d'une sépiolite sur la vitesse d'extraction des ions Mg et la variation des propriétés texturales des produits résultants. On a élaboré un modèle cinétique pour l'attaque acide de la sépiolite ce qui nous a permis de calculer les paramètres cinétiques et, en dernier lieu d'obtenir des valeurs pour l'energie d'activation du processus.
The role of diagenetic studies in production operations
Authors: Kantorowicz J. D. , Lievaart L. , Eylander J. G. R. , Eigner M. R. P.
Published: November 2006

Petrographical studies can be undertaken to investigate the effects of production operations on sandstone reservoirs and to identify the nature of any rock-fluid interaction. In combination with diagenetic models the results may be employed to predict the effects of field development programmes on reservoir mineralogy, and to avoid costly damage to the reservoir's permeability. Acidization to remove drilling mud from Reservoir A samples was undertaken in two stages to avoid adverse rock-fluid interaction. HCl dissolved siderite and chlorite but did not increase permeability. This is because the dissolved siderite released previously cemented clay particles into the pore space. A subsequent mixture of HCl and HF dissolved all the clays present in the treated area including the drilling mud, but also etched the quartz cement. Permeability increased significantly but the rock's strength decreased. This could cause an influx of loose sand during hydrocarbon production. Water injection into Reservoir B samples caused a variety of rock-fluid interactions. In finer-grained samples movement of siderite rhombs as well as clay particles blocked pores, and changes in porewater composition caused smectite to swell. Both effects caused permeability to decline. In the coarser-grained siderite-free samples, permeability improved after oil and clay particles had been displaced. In the reservoir these effects would combine to exacerbate the effects of the existing reservoir heterogeneity. Steam injection into Reservoir C samples caused mineralogical reactions. Amounts of dolomite and kaolinite decreased, and smectite and calcite were generated. This may affect the permeability of the reservoir and will determine whether oil can be produced through the affected sediment.
Comparison of sedimentary chlorite compositions by X-ray diffraction and analytical TEM
Authors: Whittle C. K.
Published: November 2006

Authigenic chlorites occurring as pore linings in reservoir sandstones have been investigated by XRD and TEM/EDAX. Both methods identified the Ib (β = 90°) polytype. TEM/EDAX analyses suggest that the chlorites are Al-rich, Mg-chamosites with Fe/(Fe + Mg) > 0·47. Octahedral Al exceeds tetrahedral Al, resulting in octahedral totals of less than the theoretical 12·0. Compositions were estimated from XRD data using the equations after Brindley (1961) and Shirozu (1958). XRD-determined compositions are relatively enriched in tetrahedral Al and octahedral Mg, giving Fe/(Fe + Mg) > 0·4 and suggesting that the chlorites are Al-rich clinochlores. XRD estimates plot in the same compositional area as authigenic Ib (β = 90°) chlorites of Hayes (1970), but also within the compositional area of metamorphic chlorites. Caution should be exercised when estimating the composition of sedimentary chlorites by XRD as results appear to overestimate Mg content because of the excess of octahedral R3+ over tetrahedral R3+.
Surgery is more cost-effective than splinting for carpal tunnel syndrome in the Netherlands: results of an economic evaluation alongside a randomized controlled trial
Authors: Korthals-de Bos Ingeborg BC , Gerritsen Annette AM , van Tulder Maurits W , Rutten-van Mölken Maureen PMH , Adèr Herman J , de Vet Henrica CW , Bouter Lex M
Published: November 2006

Background

Carpal tunnel syndrome (CTS) is a common disorder, often treated with surgery or wrist splinting. The objective of this economic evaluation alongside a randomized trial was to evaluate the cost-effectiveness of splinting and surgery for patients with CTS.

Methods

Patients at 13 neurological outpatient clinics with clinically and electrophysiologically confirmed idiopathic CTS were randomly allocated to splinting (n = 89) or surgery (n = 87). Clinical outcome measures included number of nights waking up due to symptoms, general improvement, severity of the main complaint, paraesthesia at night and during the day, and utility. The economic evaluation was performed from a societal perspective and involved all relevant costs.

Results

There were no differences in costs. The mean total costs per patient were in the surgery group EURO 2,126 compared to EURO 2,111 in the splint group. After 12 months, the success rate in the surgery group (92%) was significantly higher than in the splint group (72%). The acceptability curve showed that at a relatively low ceiling ratio of EURO 2,500 per patient there is a 90% probability that surgery is cost-effective.

Conclusion

In the Netherlands, surgery is more cost-effective compared with splinting, and recommended as the preferred method of treatment for patients with CTS.
Fetal DNA in Maternal Plasma
Authors: DENNIS LO Y.M.
Published: November 2006

Abstract:  The discovery of cell‐free fetal DNA in maternal plasma has opened up new possibilities for noninvasive prenatal diagnosis. Most of the work in this field has focused on the detection of fetal genetic markers that are distinguishable from the background maternal DNA. The feasibility of detecting fetal epigenetic markers in maternal plasma using an imprinted locus was demonstrated in 2002. This work has recently led to the development of the first universal fetal epigenetic marker, hypomethylated

maspin

, which can be used for fetal DNA detection in maternal plasma, irrespective of fetal gender and genetic polymorphisms. It is expected that many more fetal epigenetic markers that can be used in this manner will be developed over the next few years. These markers may catalyze the eventual clinical use of circulating fetal DNA for noninvasive prenatal diagnosis, such as for the detection of fetal chromosomal aneuploidies.