bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing Sensitivity of Detection of Immune Responses toMycobacterium lepraePeptides in Whole-Blood Assays
Authors: Geluk Annemieke , van der Ploeg-van Schip Jolien J. , van Meijgaarden Krista E. , Commandeur Susanna , Drijfhout Jan W. , Benckhuijsen Willemien E. , Franken Kees L. M. C. , Naafs Bernard , Ottenhoff Tom H. M.
Published: April 2010

Although worldwide leprosy prevalence has been reduced considerably following multidrug therapy, new case detection rates remain relatively stable, suggesting that transmission of infection still continues. This calls for new efforts, among which is development of assays that can identify subclinical/early-stageMycobacterium leprae-infected subjects, a likely source of transmission. Areas in which leprosy is endemic often lack sophisticated laboratories, necessitating development of field-friendly immunodiagnostic tests for leprosy, like short-term whole-blood assays (WBA). In classical, peripheral blood mononuclear cell (PBMC)-based gamma interferon (IFN-γ) release assays,M. lepraepeptides have been shown to discriminate in a more specific fashion thanM. lepraeproteins betweenM. leprae-exposed contacts and patients as opposed to healthy controls from the same area of endemicity. However, peptides induced significantly lower levels of IFN-γ than did proteins, particularly when whole blood was used. Therefore, possibilities of specifically enhancing IFN-γ production in response toM. lepraepeptides in 24-h WBA were sought by addition of various cytokines and antibodies or by mannosylation of peptides. In addition, other cytokines and chemokines were analyzed as potential biomarkers in WBA. We found that only interleukin 12 (IL-12), not other costimulants, increased IFN-γ production in WBA while maintainingM. lepraepeptide specificity, as evidenced by lack of increase of IFN-γ in control samples stimulated with IL-12 alone. The IL-12-induced increase in IFN-γ was mainly mediated by CD4+T cells that did not produce IL-2 or tumor necrosis factor (TNF). Mannosylation further allowed the use of 100-fold-less peptide. Although not statistically significantly, macrophage inflammatory protein 1β (MIP-1β) and macrophage c protein 1 (MCP-1) levels specific forM. lepraepeptide tended to be increased by IL-12. IP-10 production was also found to be a useful marker ofM. lepraepeptide responses, but its production was enhanced by IL-12 nonspecifically. We conclude that IFN-γ-based WBA combined with IL-12 represents a more sensitive and robust assay for measuring reactivity toM. lepraepeptides.
Murine Coronavirus Induces Type I Interferon in Oligodendrocytes through Recognition by RIG-I and MDA5
Authors: Li Jianfeng , Liu Yin , Zhang Xuming
Published: April 2010

The murine coronavirus mouse hepatitis virus (MHV) induced the expression of type I interferon (alpha/beta interferon [IFN-α/β]) in mouse oligodendrocytic N20.1 cells. This induction is completely dependent on virus replication, since infection with UV light-inactivated virus could no longer induce IFN-α/β. We show that MHV infection activated both transcription factors, the IFN regulatory factor 3 (IRF-3) and nuclear factor κB (NF-κB), as evidenced by phosphorylation and nuclear translocation of IRF-3 and an increased promoter binding activity for IRF-3 and NF-κB. Furthermore, the cytoplasmic pattern recognition receptor retinoic acid-inducible gene I (RIG-I) was induced by MHV infection. Knockdown of RIG-I by small interfering RNAs blocked the activation of IRF-3 and subsequent IFN-α/β production induced by MHV infection. Knockdown of another cytoplasmic receptor, the melanoma-differentiation-associated gene 5 (MDA5), by small interfering RNAs also blocked IFN-β induction. These results demonstrate that MHV is recognized by both RIG-I and MDA5 and induces IFN-α/β through the activation of the IRF-3 signaling pathway. However, knockdown of RIG-I only partially blocked NF-κB activity induced by MHV infection and inhibition of NF-κB activity by a decoy peptide inhibitor had little effect on IFN-α/β production. These data suggest that activation of the NF-κB pathway might not play a critical role in IFN-α/β induction by MHV infection in oligodendrocytes.
Human Immunodeficiency Virus Type 1 Nucleocapsid p1 Confers ESCRT Pathway Dependence
Authors: Popova Elena , Popov Sergei , Göttlinger Heinrich G.
Published: April 2010

To facilitate the release of infectious progeny virions, human immunodeficiency virus type 1 (HIV-1) exploits the Endosomal Sorting Complex Required for Transport (ESCRT) pathway by engaging Tsg101 and ALIX through late assembly (L) domains in the C-terminal p6 domain of Gag. However, the L domains in p6 are known to be dispensable for efficient particle production by certain HIV-1 Gag constructs that have the nucleocapsid (NC) domain replaced by a foreign dimerization domain to substitute for the assembly function of NC. We now show that one such L domain-independent HIV-1 Gag construct (termed Z
WT
) that has NC-p1-p6 replaced by a leucine zipper domain is resistant to dominant-negative inhibitors of the ESCRT pathway that block HIV-1 particle production. However, Z
WT
became dependent on the presence of an L domain when NC-p1-p6 was restored to its C terminus. Furthermore, when the NC domain was replaced by a leucine zipper, the p1-p6 region, but not p6 alone, conferred sensitivity to inhibition of the ESCRT pathway. In an authentic HIV-1 Gag context, the effect of an inhibitor of the ESCRT pathway on particle production could be alleviated by deleting a portion of the NC domain together with p1. Together, these results indicate that the ESCRT pathway dependence of HIV-1 budding is determined, at least in part, by the NC-p1 region of Gag.
MicroRNA miR-155 Inhibits Bone Morphogenetic Protein (BMP) Signaling and BMP-Mediated Epstein-Barr Virus Reactivation
Authors: Yin Qinyan , Wang Xia , Fewell Claire , Cameron Jennifer , Zhu Hanqing , Baddoo Melody , Lin Zhen , Flemington Erik K.
Published: April 2010

MicroRNA miR-155 is expressed at elevated levels in human cancers including cancers of the lung, breast, colon, and a subset of lymphoid malignancies. In B cells, miR-155 is induced by the oncogenic latency gene expression program of the human herpesvirus Epstein-Barr virus (EBV). Two other oncogenic herpesviruses, Kaposi's sarcoma-associated herpesvirus and Marek's disease virus, encode functional homologues of miR-155, suggesting a role for this microRNA in the biology and pathogenesis of these viruses. Bone morphogenetic protein (BMP) signaling is involved in an array of cellular processes, including differentiation, growth inhibition, and senescence, through context-dependent interactions with multiple signaling pathways. Alteration of this pathway contributes to a number of disease states including cancer. Here, we show that miR-155 targets the 3′ untranslated region of multiple components of the BMP signaling cascade, including SMAD1, SMAD5, HIVEP2, CEBPB, RUNX2, and MYO10. Targeting of these mediators results in the inhibition of BMP2-, BMP6-, and BMP7-induced ID3 expression as well as BMP-mediated EBV reactivation in the EBV-positive B-cell line, Mutu I. Further, miR-155 inhibits SMAD1 and SMAD5 expression in the lung epithelial cell line A549, it inhibits BMP-mediated induction of the cyclin-dependent kinase inhibitor p21, and it reverses BMP-mediated cell growth inhibition. These results suggest a role for miR-155 in controlling BMP-mediated cellular processes, in regulating BMP-induced EBV reactivation, and in the inhibition of antitumor effects of BMP signaling in normal and virus-infected cells.
Exchange of the Coronavirus Replicase Polyprotein Cleavage Sites Alters Protease Specificity and Processing
Authors: Gadlage Mark J. , Denison Mark R.
Published: April 2010

Coronavirus nonstructural proteins 1 to 3 are processed by one or two papain-like proteases (PLP1 and PLP2) at specific cleavage sites (CS1 to -3). Murine hepatitis virus (MHV) PLP2 and orthologs recognize and cleave at a position following a p4-Leu-X-Gly-Gly-p1 tetrapeptide, but it is unknown whether these residues are sufficient to result in processing by PLP2 at sites normally cleaved by PLP1. We demonstrate that exchange of CS1 and/or CS2 with the CS3 p4-p1 amino acids in engineered MHV mutants switches specificity from PLP1 to PLP2 at CS2, but not at CS1, and results in altered protein processing and virus replication. Thus, the p4-p1 residues are necessary for PLP2 processing but require a specific protein or cleavage site context for optimal PLP recognition and cleavage.
Activation of the Inositol (1,4,5)-Triphosphate Calcium Gate Receptor Is Required for HIV-1 Gag Release
Authors: Ehrlich Lorna S. , Medina Gisselle N. , Khan Mahfuz B. , Powell Michael D. , Mikoshiba Katsuhiko , Carter Carol A.
Published: April 2010

The structural precursor polyprotein, Gag, encoded by all retroviruses, including the human immunodeficiency virus type 1 (HIV-1), is necessary and sufficient for the assembly and release of particles that morphologically resemble immature virus particles. Previous studies have shown that the addition of Ca
2+
to cells expressing Gag enhances virus particle production. However, no specific cellular factor has been implicated as mediator of Ca
2+
provision. The inositol (1,4,5)-triphosphate receptor (IP3R) gates intracellular Ca
2+
stores. Following activation by binding of its ligand, IP3, it releases Ca
2+
from the stores. We demonstrate here that IP3R function is required for efficient release of HIV-1 virus particles. Depletion of IP3R by small interfering RNA, sequestration of its activating ligand by expression of a mutated fragment of IP3R that binds IP3 with very high affinity, or blocking formation of the ligand by inhibiting phospholipase C-mediated hydrolysis of the precursor, phosphatidylinositol-4,5-biphosphate, inhibited Gag particle release. These disruptions, as well as interference with ligand-receptor interaction using antibody targeted to the ligand-binding site on IP3R, blocked plasma membrane accumulation of Gag. These findings identify IP3R as a new determinant in HIV-1 trafficking during Gag assembly and introduce IP3R-regulated Ca
2+
signaling as a potential novel cofactor in viral particle release.
Nuclear RNA Export and Packaging Functions of HIV-1 Rev Revisited
Authors: Blissenbach Maik , Grewe Bastian , Hoffmann Bianca , Brandt Sabine , Überla Klaus
Published: April 2010

Although the viral Rev protein is necessary for HIV replication, its main function in the viral replication cycle has been controversial. Reinvestigating the effect of Rev on the HIV-1 RNA distribution in various cell lines and primary cells revealed that Rev enhanced cytoplasmic levels of the unspliced HIV-1 RNA, mostly 3- to 12-fold, while encapsidation of the RNA and viral infectivity could be stimulated >1,000-fold. Although this clearly questions the general notion that the nuclear export of viral RNAs is the major function of Rev, mechanistically encapsidation seems to be linked to nuclear export, since the tethering of the nuclear export factor TAP to the HIV-1 RNA also enhanced encapsidation. Interference with the formation of an inhibitory ribonucleoprotein complex in the nucleus could lead to enhanced accessibility of the cytoplasmic HIV-1 RNA for translation and encapsidation. This might explain why Rev and tethered TAP exert the same pattern of pleiotropic effects.
SRp40 and SRp55 Promote the Translation of Unspliced Human Immunodeficiency Virus Type 1 RNA
Authors: Swanson Chad M. , Sherer Nathan M. , Malim Michael H.
Published: April 2010

Nuclear RNA processing events, such as 5′ cap formation, 3′ polyadenylation, and pre-mRNA splicing, mark mRNA for efficient translation. Splicing enhances translation via the deposition of the exon-junction complex and other multifunctional splicing factors, including SR proteins. All retroviruses synthesize their structural and enzymatic proteins from unspliced genomic RNAs (gRNAs) and must therefore exploit unconventional strategies to ensure their effective expression. Here, we report that specific SR proteins, particularly SRp40 and SRp55, promote human immunodeficiency virus type 1 (HIV-1) Gag translation from unspliced (intron-containing) viral RNA. This activity does not correlate with nucleocytoplasmic shuttling capacity and, in the case of SRp40, is dependent on the second RNA recognition motif and the arginine-serine (RS) domain. While SR proteins enhance Gag expression independent of RNA nuclear export pathway choice, altering the nucleotide sequence of the
gag-pol
coding region by codon optimization abolishes this effect. We therefore propose that SR proteins couple HIV-1 gRNA biogenesis to translational utilization.
Residues Surrounding the Glycosylphosphatidylinositol Anchor Attachment Site of PrP Modulate Prion Infection: Insight from the Resistance of Rabbits to Prion Disease
Authors: Nisbet Rebecca M. , Harrison Christopher F. , Lawson Victoria A. , Masters Colin L. , Cappai Roberto , Hill Andrew F.
Published: April 2010

Prion diseases are a group of transmissible, invariably fatal neurodegenerative diseases that affect both humans and animals. According to the protein-only hypothesis, the infectious agent is a prion (proteinaceous infectious particle) that is composed primarily of PrP
Sc
, the disease-associated isoform of the cellular prion protein, PrP. PrP
Sc
arises from the conformational change of the normal, glycosylphosphatidylinositol (GPI)-anchored protein, PrP
C
. The mechanism by which this process occurs, however, remains enigmatic. Rabbits are one of a small number of mammalian species reported to be resistant to prion infection. Sequence analysis of rabbit PrP revealed that its C-terminal amino acids differ from those of PrP from other mammals and may affect the anchoring of rabbit PrP through its GPI anchor. Using a cell culture model, this study investigated the effect of the rabbit PrP-specific C-terminal amino acids on the addition of the GPI anchor to PrP
C
, PrP
C
localization, and PrP
Sc
formation. The incorporation of rabbit-specific C-terminal PrP residues into mouse PrP did not affect the addition of a GPI anchor or the localization of PrP. However, these residues did inhibit PrP
Sc
formation, suggesting that these rabbit-specific residues interfere with a C-terminal PrP
Sc
interaction site.
FACTORIZATION EFFECTS IN A MODEL OF UNSTABLE PARTICLES
Authors: KUKSA V. I. , VOLCHANSKIY N. I.
Published: April 2010

The effects of factorization are considered within the framework of the model of unstable particles with a smeared mass. It is shown that two-particle cross-section and three-particle decay width can be described by the universal factorized formulae for an unstable particles of an arbitrary spin in an intermediate state. The exact factorization is caused by the specific structure of the model unstable-particle propagators. This result is generalized to complicated scattering and decay-chain processes with unstable particles in intermediate states. We analyze applicability of the method and evaluate its accuracy.
TILECAL: THE HADRONIC SECTION OF THE CENTRAL ATLAS CALORIMETER
Authors: ANDERSON K. , DEL PRETE T. , FULLANA E. , HUSTON J. , RODA C. , STANEK R.
Published: April 2010

This paper describes the concepts behind the TileCal design, as well as the requirements and the constraints that have finally produced the ATLAS central hadronic calorimeter.
Adenosine A3receptor stimulation induces protection of skeletal muscle from eccentric exercise-mediated injury
Authors: Wang Ruibo , Urso Maria L. , Zambraski Edward J. , Rader Erik P. , Campbell Kevin P. , Liang Bruce T.
Published: April 2010

Effective therapy to reduce skeletal muscle injury associated with severe or eccentric exercise is needed. The purpose of this study was to determine whether adenosine receptor stimulation can mediate protection from eccentric exercise-induced muscle injury. Downhill treadmill exercise (−15°) was used to induce eccentric exercise-mediated skeletal muscle injury. Experiments were conducted in both normal wild-type (WT) mice and also in β-sarcoglycan knockout dystrophic mice, animals that show an exaggerated muscle damage with the stress of exercise. In the vehicle-treated WT animals, eccentric exercise increased serum creatine kinase (CK) greater than 3-fold to 358.9 ± 62.7 U/l (SE). This increase was totally abolished by stimulation of the A3receptor. In the dystrophic β-sarcoglycan-null mice, eccentric exercise caused CK levels to reach 55,124 ± 5,558 U/l. A3receptor stimulation in these animals reduced the CK response by nearly 50%. In the dystrophic mice at rest, 10% of the fibers were found to be damaged, as indicated by Evans blue dye staining. While this percentage was doubled after exercise, A3receptor stimulation eliminated this increase. Neither the A1receptor agonist 2-chloro- N6-cyclopentyladenosine (0.05 mg/kg) nor the A2Areceptor agonist 2- p-(2-carboxyethyl)phenethylamino-5′- N-ethylcarboxamidoadenosine (0.07 mg/kg) protected skeletal muscle from eccentric exercise injury in WT or dystrophic mice. The protective effect of adenosine A3receptor stimulation was absent in mice, in which genes for phospholipase C β2/β3 (PLCβ2/β3) and β-sarcoglycan were deleted. The present study elucidates a new protective role of the A3receptor and PLCβ2/β3 and points to a potentially effective therapeutic strategy for eccentric exercise-induced skeletal muscle injury.
The molecular basis of aerobic metabolic remodeling differs between oxidative muscle and liver of threespine sticklebacks in response to cold acclimation
Authors: Orczewska J. I. , Hartleben G. , O'Brien K. M.
Published: April 2010

We sought to determine the molecular basis of elevations in aerobic metabolic capacity in the oxidative muscle and liver of Gasterosteus aculeatus in response to cold acclimation. Fishes were cold- or warm-acclimated for 9 wk and harvested on days 1, 2, and 3 and weeks 1, 4, and 9 of cold acclimation at 8°C, and on day 1 and week 9 of warm acclimation at 20°C. Mitochondrial volume density was quantified using transmission electron microscopy and stereological techniques in warm- and cold-acclimated fishes harvested after 9 wk at 20 or 8°C. Changes in aerobic metabolic capacity were assessed by measuring the maximal activity of citrate synthase (CS) and cytochrome- c oxidase (COX) in fishes harvested throughout the acclimation period. Transcript levels of the aerobic metabolic genes CS, COXIII, and COXIV, and known regulators of mitochondrial biogenesis, including peroxisome proliferator-activated receptor-γ coactivators-1α and -1β (PGC-1α and PGC-1β), nuclear respiratory factor-1 (NRF-1), and mitochondrial transcription factor-A were measured in fishes harvested throughout the acclimation period using quantitative real-time PCR. The maximal activities of CS and COX increased in response to cold acclimation in both tissues, but mitochondrial volume density only increased in oxidative muscle ( P < 0.05). The time course for changes in aerobic metabolic capacity differed between liver and muscle. The expression of CS increased within 1 wk of cold acclimation in liver and was correlated with an increase in mRNA levels of NRF-1 and PGC-1β. Transcript levels of aerobic metabolic genes increased later in oxidative muscle, between weeks 4 and 9 of cold acclimation and were correlated with an increase in mRNA levels of NRF-1 and PGC-1α. These results show that aerobic metabolic remodeling differs between liver and muscle in response to cold acclimation and may be triggered by different stimuli.
Dot1a contains three nuclear localization signals and regulates the epithelial Na+channel (ENaC) at multiple levels
Authors: Reisenauer Mary Rose , Wang Steven W. , Xia Yang , Zhang Wenzheng
Published: April 2010

We have previously reported that Dot1a is located in the cytoplasm and nucleus (Reisenauer MR, Anderson M, Huang L, Zhang Z, Zhou Q, Kone BC, Morris AP, Lesage GD, Dryer SE, Zhang W. J Biol Chem 284: 35659–35669, 2009), widely expressed in the kidney as detected by its histone H3K79 methyltransferase activity (Zhang W, Hayashizaki Y, Kone BC. Biochem J 377: 641–651, 2004), and involved in transcriptional control of the epithelial Na+channel subunit-α gene ( αENaC) (Zhang W, Xia X, Jalal DI, Kuncewicz T, Xu W, Lesage GD, Kone BC. Am J Physiol Cell Physiol 290: C936–C946, 2006). Aldosterone releases repression of αENaC by reducing expression of Dot1a and its partner AF9 (Zhang W, Xia X, Reisenauer MR, Hemenway CS, Kone BC. J Biol Chem 281: 18059–18068, 2006) and by impairing Dot1a-AF9 interaction via Sgk1-mediated AF9 phosphorylation (Zhang W, Xia X, Reisenauer MR, Rieg T, Lang F, Kuhl D, Vallon V, Kone BC. J Clin Invest 117: 773–783, 2007). This network also appears to regulate transcription of several other aldosterone target genes. Here, we provide evidence showing that Dot1a contains at least three potential nuclear localization signals (NLSs). Deletion of these NLSs causes green fluorescent protein-fused Dot1a fusions to localize almost exclusively in the cytoplasm of 293T cells as revealed by confocal microscopy. Deletion of NLSs abolished Dot1a-mediated repression of αENaC-promoter luciferase construct in M1 cells. AF9 is widely expressed in mouse kidney. Similar to αENaC, the mRNA levels of βENaC, γENaC, and Sgk1 are also downregulated by Dot1a and AF9 overexpression. Small interference RNA-mediated knockdown of Dot1a and AF9 or aldosterone treatment leads to an opposite effect. Using single-cell fluorescence imaging or equivalent short-circuit current in IMCD3 and M1 cells, we show that observed transcriptional alterations correspond to changes in ENaC and Sgk1 protein levels as well as benzamil-sensitive Na+transport. In brief, Dot1a and AF9 downregulate Na+transport, most likely by regulating ENaC mRNA and subsequent protein expression and ENaC activity.
Effect of chronic alcohol feeding on physiological and molecular parameters of renal thiamin transport
Authors: Subramanian Veedamali S. , Subramanya Sandeep B. , Tsukamoto Hidekazu , Said Hamid M.
Published: April 2010

The renal thiamin reabsorption process plays an important role in regulating thiamin body homeostasis and involves both thiamin transporters-1 and -2 (THTR1 and THTR2). Chronic alcohol use is associated with thiamin deficiency. Although a variety of factors contribute to the development of this deficiency, effects of chronic alcohol use on renal thiamin transport have not been thoroughly examined. We addressed this issue by examining the effect of chronic alcohol feeding of rats with liquid diet on physiological and molecular parameters of renal thiamin transport. Chronic alcohol feeding caused a significant inhibition in carrier-mediated thiamin transport across the renal brush-border membrane and was evident as early as 2 wk after initiation of alcohol feeding. Similarly, thiamin transport across the renal basolateral membrane was significantly inhibited by chronic alcohol feeding. The inhibition in renal thiamin transport was associated with a marked decrease in the level of expression of THTR1 and -2 proteins, mRNAs, and heterogeneous nuclear RNAs. Chronic alcohol feeding also caused a significant reduction in the level of expression of thiamin pyrophosphokinase but not that of the mitochondrial thiamin pyrophosphate transporter. These studies show that chronic alcohol feeding inhibits the entry and exit of thiamin in the polarized renal epithelial cells and that the effect is, at least in part, mediated at the transcriptional level. These findings also suggest that chronic alcohol feeding interferes with the normal homeostasis of thiamin in renal epithelial cells.
Ouabain stimulates Na-K-ATPase through a sodium/hydrogen exchanger-1 (NHE-1)-dependent mechanism in human kidney proximal tubule cells
Authors: Holthouser Kristine A. , Mandal Amritlal , Merchant Michael L. , Schelling Jeffrey R. , Delamere Nicholas A. , Valdes Ronald R. , Tyagi Suresh C. , Lederer Eleanor D. , Khundmiri Syed J.
Published: April 2010

Recent investigations demonstrate increased Na/H exchanger-1 (NHE-1) activity and plasma levels of ouabain-like factor in spontaneously hypertensive rats. At nanomolar concentrations, ouabain increases Na-K-ATPase activity, induces cell proliferation, and activates complex signaling cascades. We hypothesize that the activity of NHE-1 and Na-K-ATPase are interdependent. To test whether treatment with picomolar ouabain regulates Na-K-ATPase through an NHE-1-dependent mechanism, we examined the role of NHE-1 in ouabain-mediated stimulation of Na-K-ATPase in kidney proximal tubule cell lines [opossum kidney (OK), HK-2, HKC-5, and HKC-11] and rat kidney basolateral membranes. Ouabain stimulated Na-K-ATPase activity and tyrosine phosphorylation in cells that express NHE-1 (OK, HKC-5, and HKC-11) but not in HK-2 cells that express very low levels of NHE-1. Inhibition of NHE-1 with 5 μM EIPA, a NHE-1-specific inhibitor, prevented ouabain-mediated stimulation of86Rb uptake and Na-K-ATPase phosphorylation in OK, HKC-5, and HKC-11 cells. Expression of wild-type NHE-1 in HK2 cells restored regulation of Na-K-ATPase by picomolar ouabain. Treatment with picomolar ouabain increased membrane expression of Na-K-ATPase and enhanced NHE-1-Na-K-ATPase α1-subunit association. Treatment with ouabain (1 μg·kg body wt−1·day−1) increased Na-K-ATPase activity, expression, phosphorylation, and association with NHE-1 increased in rat kidney cortical basolateral membranes. Eight days' treatment with ouabain (1 μg·kg body wt−1·day−1) resulted in increased blood pressure in these rats. These results suggest that the association of NHE-1 with Na-K-ATPase is critical for ouabain-mediated regulation of Na-K-ATPase and that these effects may play a role in cardioglycoside-stimulated hypertension.
Lysosomal Storage Disease: Revealing Lysosomal Function and Physiology
Authors: Parkinson-Lawrence Emma J. , Shandala Tetyana , Prodoehl Mark , Plew Revecca , Borlace Glenn N. , Brooks Doug A.
Published: April 2010

The discovery over five decades ago of the lysosome, as a degradative organelle and its dysfunction in lysosomal storage disorder patients, was both insightful and simple in concept. Here, we review some of the history and pathophysiology of lysosomal storage disorders to show how they have impacted on our knowledge of lysosomal biology. Although a significant amount of information has been accrued on the molecular genetics and biochemistry of lysosomal storage disorders, we still do not fully understand the mechanistic link between the storage material and disease pathogenesis. However, the accumulation of undegraded substrate(s) can disrupt other lysosomal degradation processes, vesicular traffic, and lysosomal biogenesis to evoke the diverse pathophysiology that is evident in this complex set of disorders.
A New High‐Speed Foreign Fiber Detection System with Machine Vision
Authors: Chen Zhiguo , Xu Wenbo , Leng Wenhao , Fu Yi
Published: April 2010

A new high‐speed foreign fiber detection system with machine vision is proposed for removing foreign fibers from raw cotton using optimal hardware components and appropriate algorithms designing. Starting from a specialized lens of 3‐charged couple device (CCD) camera, the system applied digital signal processor (DSP) and field‐programmable gate array (FPGA) on image acquisition and processing illuminated by ultraviolet light, so as to identify transparent objects such as polyethylene and polypropylene fabric from cotton tuft flow by virtue of the fluorescent effect, until all foreign fibers that have been blown away safely by compressed air quality can be achieved. An image segmentation algorithm based on fast wavelet transform is proposed to identify block‐like foreign fibers, and an improved canny detector is also developed to segment wire‐like foreign fibers from raw cotton. The procedure naturally provides color image segmentation method with region growing algorithm for better adaptability. Experiments on a variety of images show that the proposed algorithms can effectively segment foreign fibers from test images under various circumstances.
Successful Endoscopic Injection Sclerotherapy of High-Risk Gastroesophageal Varices in a Cirrhotic Patient with Hemophilia A
Authors: Fukumoto Kohei , Konishi Hideyuki , Soga Koichi , Miyawaki Ki-ichiro , Okano Hitoshi , Minami Masahito , Wakabayashi Naoki , Mitsufuji Shoji , Yoshida Norimasa , Takagi Tomohisa , Yagi Nobuaki , Naito Yuji , Kataoka Keisho , Yoshikawa Toshikazu
Published: April 2010

A 68-year-old man with hemophilia A and liver cirrhosis caused by hepatitis C virus was referred to our hospital to receive prophylactic endoscopic treatment for gastroesophageal varices (GOV). He had large, tense, and winding esophageal varices (EV) with cherry red spots extending down to lesser curve, predicting the likelihood of bleeding. Esophageal endoscopic injection sclerotherapy (EIS) was performed with a total 15 mL of 5% ethanolamine oleate with iopamidol (EOI). Radiographic imaging during EIS demonstrated that 5% EOI reached the afferent vein of the varices. He was administered sufficient factor VIII concentrate before and after EIS to prevent massive bleeding from the varices. Seven days after EIS, upper gastrointestinal endoscopy (UGIE) showed that the varices were eradicated almost completely. Eighteen months after EIS, the varices continued to diminish. We report a successful case of safe and effective EIS for GOV in a high-risk cirrhotic patient with hemophilia A.
Multivariate Autoregressive Modeling and Granger Causality Analysis of Multiple Spike Trains
Authors: Krumin Michael , Shoham Shy
Published: April 2010

Recent years have seen the emergence of microelectrode arrays and optical methods allowing simultaneous recording of spiking activity from populations of neurons in various parts of the nervous system. The analysis of multiple neural spike train data could benefit significantly from existing methods for multivariate time-series analysis which have proven to be very powerful in the modeling and analysis of continuous neural signals like EEG signals. However, those methods have not generally been well adapted to point processes. Here, we use our recent results on correlation distortions in multivariate Linear-Nonlinear-Poisson spiking neuron models to derive generalized Yule-Walker-type equations for fitting ‘‘hidden’’ Multivariate Autoregressive models. We use this new framework to perform Granger causality analysis in order to extract the directed information flow pattern in networks of simulated spiking neurons. We discuss the relative merits and limitations of the new method.
Crossings of Second‐Order Response Processes Subjected to LMA Loadings
Authors: Galtier Thomas , Gupta Sayan , Rychlik Igor
Published: April 2010

The focus of this paper is on the estimation of the crossing intensities of responses for second‐order dynamical systems, subjected to stationary, non‐Gaussian external loadings. A new model for random loadings—the Laplace driven moving average (LMA)—is used. The model is non‐Gaussian, strictly stationary, can model any spectrum, and has additional flexibility to model the skewness and kurtosis of the marginal distribution. The system response can be expressed as a second‐order combination of the LMA processes. A numerical technique for estimating the level crossing intensities for such processes is developed. The proposed method is a hybrid method which combines the saddle‐point approximation with limited Monte Carlo simulations. The performance and the accuracy of the proposed method are illustrated through a set of numerical examples.
Triggering DTH and CTL Activity by fd Filamentous Bacteriophages: Role of CD4+ T Cells in Memory Responses
Authors: Del Pozzo Giovanna , Mascolo Dina , Sartorius Rossella , Citro Alessandra , Barba Pasquale , D'Apice Luciana , De Berardinis Piergiuseppe
Published: April 2010

The ability of fd bacteriophage particles to trigger different arms of the immune system has been previously shown by us with particular emphasis on the ability of phages to raise CTL responses in vitro and in vivo. Here we show that fd virions in the absence of adjuvants are able to evoke a DTH reaction mediated by antigen specific CD8+ T cells. In addition, we analyzed the induction of CTL responses in mice depleted of CD4+ T cells, and we observed that short-term secondary CTL responses were induced in the absence of CD4+ T cells while induction of long-term memory CTLs required the presence of CD4+ T lymphocytes. These results examine the cellular mechanism at the basis of fd efficiency and provide new elements to further validate the use of fd particles for eliciting and monitoring antigen-specific CTLs.
Receptor-Mediated Transcytosis of Leptin through Human Intestinal Cells In Vitro
Authors: Cammisotto Philippe G. , Bendayan Moise , Sané Alain , Dominguez Michel , Garofalo Carole , Levy Émile
Published: April 2010

Gastric Leptin is absorbed by duodenal enterocytes and released on the basolateral side towards the bloodstream. We investigated in vitro some of the mechanisms of this transport. Caco-2/15 cells internalize leptin from the apical medium and release it through transcytosis in the basal medium in a time- temperature-dependent and saturable fashion. Leptin receptors are revealed on the apical brush-border membrane of the Caco-2 cells. RNA-mediated silencing of the receptor led to decreases in the uptake and basolateral release. Leptin in the basal medium was found bound to the soluble form of its receptor. An inhibitor of clathrin-dependent endocytosis (chlorpromazine) decreased leptin uptake. Confocal immunocytochemistry and the use of brefeldin A and okadaic acid revealed the passage of leptin through the Golgi apparatus. We propose that leptin transcytosis by intestinal cells depends on its receptor, on clathrin-coated vesicles and transits through the Golgi apparatus.
Renormalization, Isogenies, and Rational Symmetriesof Differential Equations
Authors: Bostan A. , Boukraa S. , Hassani S. , Maillard J.-M. , Weil J.-A. , Zenine N. , Abarenkova N.
Published: April 2010

We give an example of infinite‐order rational transformation that
leaves a linear differential equation covariant. This example can be seen as a nontrivial
but still simple illustration of an exact representation of the renormalization
group.
Integration of Epidermal Growth Factor Receptor Inhibitors with Preoperative Chemoradiation
Authors: Debucquoy Annelies , Machiels Jean-Pascal , McBride William H. , Haustermans Karin
Published: April 2010

In many different cancer cell types, the epidermal growth factor receptor (EGFR) pathway becomes hyperactivated because of overproduction of the ligand, overproduction of the receptor, or constitutive activation of the receptor. The overproduction of EGFR and its ligands correlates with poor prognosis in several solid tumors such as lung, colon, and ovary. These observations led to the development of EGFR inhibitors for anticancer treatment. In the last few years, promising results have been obtained in several tumor types, with EGFR inhibitors given as monotherapy or in combined treatments. In particular, cetuximab in combination with curative-intent radiotherapy in head and neck cancer increases median survival over radiation alone. Similarly, the same approach might benefit patients with locally advanced rectal cancer. Unfortunately, the first clinical studies combining chemoradiation with cetuximab in rectal cancer gave disappointing results. Translational research suggested that the low response rate observed might have been due to the strong antiproliferative effect of cetuximab that may have compromised the activity of chemotherapeutics that target proliferating cells. This result indicates the need for more translational research to unravel how the molecular mechanisms might be manipulated to optimize the combined treatment regimen and to identify biomarkers that can select those patients who will derive most benefit. Clin Cancer Res; 16(10); 2709–14. ©2010 AACR.
Characteristics, Cardiovascular Comorbidity and Medicines Management in Patients with Type 2 Diabetes and CKD: Results of the IRIDIEM Study
Authors: Stevens P.E. , Schernthaner G. , Raptis S. , Wanner C. , Scherhag A. , Lameire N.
Published: April 2010

Background: Type 2 diabetes is a leading cause of chronic kidney disease (CKD). The purpose of the Individual Risk-Profiling and Treatment in Diabetes Management (IRIDIEM) study was to evaluate the characteristics of CKD and associated comorbidities in patients with type 2 diabetes and CKD. Methods: IRIDIEM was conducted as a cross-sectional survey in 109 centres in 11 countries and included 1,205 patients aged ≧50 years with type 2 diabetes for ≧5 years and CKD stage 2–4. Results: 50% of patients were in CKD stage 4; 42% had CKD stage 3, and 4% were in CKD stage 2. Concomitant risk factors for cardiovascular disease and/or progression of CKD included hypertension (92% of patients), proteinuria (74%), hypercholesterolaemia (65%), and hypertriglyceridaemia (44%). Only 64% of patients with hypertension had received antihypertensive medication. Anaemia was present in 34% of patients and increased markedly with advanced CKD stages. Of patients with documented anaemia, only 19% had received epoetin and only 7% had received iron treatment. Conclusion: IRIDIEM documents the need to improve adherence to current best practice guidelines for management of cardiorenal risk factors including earlier initiation of antihypertensive treatment, lipid and anaemia management in this high-risk patient population.
Effects of Statins on Progression of Subclinical Brain Infarct
Authors: Fu Jian Hui , Mok Vincent , Lam Wynnie , Wong Adrian , Chu Winnie , Xiong Yunyun , Ng Ping Wing , Tsoi Tak Hon , Yeung Vincent , Wong Ka Sing
Published: April 2010

Background: Subclinical brain infarct (SBI) is associated with subsequent stroke and cognitive decline. A longitudinal epidemiological study suggests that statins may prevent development of SBI. We investigated the effects of statins upon development of brain infarct by performing a post-hoc analysis of the Regression of Cerebral Artery Stenosis (ROCAS) study. Methods: The ROCAS study is a randomized, double-blind, placebo-controlled study evaluating the effects of simvastatin 20 mg daily upon progression of asymptomatic middle cerebral artery stenosis among stroke-free individuals over 2 years. A total of 227 subjects were randomized to either placebo (n = 114) or simvastatin 20 mg daily (n = 113). The number of brain infarcts as detected by MRI was recorded at baseline and at the end of the study. The primary outcome measure was the number of new brain infarcts at the end of the study. Results: Among the 227 randomized subjects, 33 (14.5%) had SBI at baseline. At the end of the study, significantly fewer subjects in the active group (n = 1) had new brain infarcts compared with the placebo group (n = 8; p = 0.018). The new brain infarcts of subjects in the active group were subclinical. Among the placebo group, the new brain infarcts of 3 subjects were symptomatic while those of the remaining 5 subjects were subclinical. Among putative variables, multivariate regression analysis showed that only the baseline number of SBIs (OR = 6.27, 95% CI 2.4–16.5) and simvastatin treatment (OR = 0.09, 95% CI 0.01–0.82) independently predicted the development of new brain infarcts. Conclusions: Consistent with findings of the epidemiological study, our study suggests that statins may prevent the development of a new brain infarct.
Training General Practitioners in the Treatment of Functional Somatic Symptoms: Effects on Patient Health in a Cluster-Randomised Controlled Trial (the Functional Illness in Primary Care Study)
Authors: Toft Tomas , Rosendal Marianne , Ørnbøl Eva , Olesen Frede , Frostholm Lisbeth , Fink Per
Published: April 2010

Background: Patients with medically unexplained or functional somatic symptoms (FSS) are prevalent in primary care. In this pragmatic cluster-randomised controlled trial we aimed to test the effect of a training programme (The Extended Reattribution and Management model) for general practitioners (GPs) in the treatment of FSS. Methods: 38 participating GPs were randomised to the control group or the training group. The GPs included consecutive 18- to 65-year-old patients presenting during a 3-week period for new health complaints. We assessed a stratified subsample with the psychiatric interview Schedules of Clinical Assessment in Neuropsychiatry. Of 701 patients interviewed, 350 fulfilled the diagnostic criteria for any ICD-10 somatoform disorder (SD) and 111 presented FSS without fulfilling these criteria (sub-threshold SD). Patients completed questionnaires at baseline and after 3, 12 and 24 months. The questionnaires included assessment of health status (36-item Medical Outcomes Study Short Form; SF-36), health anxiety (Whiteley-7) and physical symptoms (Symptom Check List-90, somatization subscale). Results: Patients with SD consulting trained GPs improved more on our primary outcome of physical functioning than patients consulting control GPs at the 3-month follow-up (p = 0.004), but the improvement was not statistically significant at later follow-up. We found no significant differences in improvement between patients with SD and those with sub-threshold SD. Results for other SF-36 subscales, physical symptoms and health anxiety only showed statistically significant differences between the intervention and control groups for patients with SD; patients consulting trained GPs had less improvement in vitality, health anxiety and physical symptoms at 24 months compared with the control group. Conclusions: GP training may accelerate improvement in physical functioning for patients with SD. However, the effect is small and may not be clinically significant.
Anti-Aging Medicine: Molecular Basis for Endothelial Cell-Targeted Strategies – A Mini-Review
Authors: Camici Giovanni G. , Shi Yi , Cosentino Francesco , Francia Pietro , Lüscher Thomas F.
Published: April 2010

Due to improvements in lifestyle and healthcare, the proportion of aged people is rising steadily, especially in developed countries. With aging, some physiological functions are altered and resemble those occurring in disease conditions such as hypertension, chronic coronary disease and diabetes. Thus, there is the urge to better understand molecular and cellular mechanisms underlying aging and aging-related diseases. In rodents and possibly primates, calorie restriction is an effective approach to extend lifespan by reducing free radical-induced damage. Increased production of oxygen-derived free radicals plays an important role in the process of aging. Reactive oxygen species are generated by different intracellular molecular pathways principally located in the cytoplasm and in the mitochondria. The mitochondrial protein p66Shc is considered a longevity assurance gene since its genetic deletion extends the lifespan of rodents and displays protective effects in several models of cardiovascular disease. Silent mating type information regulation 2 homolog 1 Saccharomyces cerevisiae (SIRT1) is a nicotinamide adenine dinucleotide (NAD+)-dependent histone deacetylase that may also be involved in aging and diseases. SIRT1 also deacetylates a number of nonhistone target proteins, including p53, endothelial nitric oxide synthase and forkhead box protein. This review focuses on the latest scientific advances in understanding aging as well as delineates the possible therapeutic implications of p66Shc and SIRT1 in this process.
Total tissue factor pathway inhibitor and venous thrombosis
Authors: Lutsey Pamela , Folsom Aaron , Heckbert Susan , Cushman Mary , Zakai Neil
Published: April 2010

Tissue factor pathway inhibitor (TFPI) inhibits tissue factor, a potent coagulation initiator. Limited evidence suggests that low TFPI levels are associated with increased risk of venous thromboembolism (VTE). We measured total TFPI in a nested case-control study in the Longitudinal Investigation of Thromboembolism Etiology. Control subjects were frequency matched 2:1 to cases on age, sex, race, and cohort. Odds ratios (ORs) for VTE by TFPI levels were computed using logistic regression models adjusting for age, race, sex, coagulation factors (factors VII, VIII, IX, XI, D-dimer), and body mass index (BMI). To evaluate for greater than additive interactions, we calculated the percent relative excess risk due to interaction between TFPI and other VTE risk factors. A total of 534 cases of VTE occurred and matched to 1,091 controls. Mean baseline TFPI in ng/ml (standard deviation) in those who developed VTE and controls was 36.4 (12.8) and 35.0 (11.1), respectively. Higher TFPI was associated with male sex, age, BMI, factors VII, VIII, IX, XI, and D-dimer. TFPI level did not differ by ethnicity, factor V Leiden, or pro-thrombin G20210A. Compared with those in the upper 95%, the bottom 5% of TFPI had an age-, sex-, race-, and study-adjusted OR (95% CI) of 1.35 (0.86, 2.12) for VTE. Adjusting for factors VII, VIII, IX, and XI the OR was 1.93 (1.05, 3.53). Further addition of D-dimer and BMI to this model decreased the OR to 1.70 (0.98, 2.93). Low TFPI did not demonstrate greater than additive interaction with other VTE risk factors.
Candida albicans and its metabolite gliotoxin inhibit platelet function via interaction with thiols
Authors: Bertling Anne , Niemann Silke , Uekötter Andreas , Fegeler Wolfgang , Lass-Flörl Cornelia , von Eiff Christof , Kehrel Beate
Published: April 2010

Platelets bind to Candida albicans, the major cause of candidiasis. But in contrast to other microorganisms the fungus does not aggregate platelets. Gliotoxin (GT), which possesses immunosuppressive properties, is produced by various fungi, including the opportunistic pathogens Aspergillus fumigatus and C. albicans. Its mode of action involves the formation of mixed disulfides with host proteins. Disulfide exchanges play an important role in platelet activation. Therefore, the effect of C. albicans and GT on platelet function was tested. C. albicans yeast cells (5,000–10,000 cells/μl) and GT, in pathophysiologically relevant concentrations (0.05–0.5 μM), inhibited platelet fibrinogen binding, anti gp IIb/IIIa antibody PAC-1 binding, aggregation and procoagulant activity in a dose-dependent manner. Alpha granule release, measured via CD62P surface expression, was not affected. Addition of reduced glutathione partially counteracted the effect of C. albicans and GT on platelet fibrinogen binding and platelet aggregation. The C. albicans metabolite GT features antithrombotic properties in addition to its immunosuppressive functions. Since treatment with reduced glutathione partially counteracted the inhibitory effect of C. albicans yeast cells and GT on platelet fibrinogen binding, the antithrombotic activity is likely to depend on the disulfide bridge of this mycotoxin. GT production by C. albicans could contribute to its survival in the blood stream during vascular infections. The knowledge of the underlying mechanisms of the antithrombotic properties might help to treat fungal infections as well as thrombosis.