bluuebunny/crossref_metadata_2025 huggingface dataset:
Syntrophorhabdus aromaticivoransgen. nov., sp. nov., the First Cultured Anaerobe Capable of Degrading Phenol to Acetate in Obligate Syntrophic Associations with a Hydrogenotrophic Methanogen
Authors: Qiu Yan-Ling , Hanada Satoshi , Ohashi Akiyoshi , Harada Hideki , Kamagata Yoichi , Sekiguchi Yuji
Published: February 2008

Phenol degradation under methanogenic conditions has long been studied, but the anaerobes responsible for the degradation reaction are still largely unknown. An anaerobe, designated strain UIT, was isolated in a pure syntrophic culture. This isolate is the first tangible, obligately anaerobic, syntrophic substrate-degrading organism capable of oxidizing phenol in association with an H2-scavenging methanogen partner. Besides phenol, it could metabolizep-cresol, 4-hydroxybenzoate, isophthalate, and benzoate. During the degradation of phenol, a small amount of 4-hydroxybenzoate (a maximum of 4 μM) and benzoate (a maximum of 11 μM) were formed as transient intermediates. When 4-hydroxybenzoate was used as the substrate, phenol (maximum, 20 μM) and benzoate (maximum, 92 μM) were detected as intermediates, which were then further degraded to acetate and methane by the coculture. No substrates were found to support the fermentative growth of strain UITin pure culture, although 88 different substrates were tested for growth. 16S rRNA gene sequence analysis indicated that strain UITbelongs to an uncultured clone cluster (group TA) at the family (or order) level in the classDeltaproteobacteria. Syntrophorhabdus aromaticivoransgen. nov., sp. nov., is proposed for strain UIT, and the novel familySyntrophorhabdaceaefam. nov. is described. Peripheral 16S rRNA gene sequences in the databases indicated that the proposed new familySyntrophorhabdaceaeis largely represented by abundant bacteria within anaerobic ecosystems mainly decomposing aromatic compounds.
Natural Populations of
Saccharomyces kudriavzevii
in Portugal Are Associated with Oak Bark and Are Sympatric with
S. cerevisiae
and
S. paradoxus
Authors: Sampaio José Paulo , Gonçalves Paula
Published: February 2008

Here we report the isolation of four
Saccharomyces
species (former
Saccharomyces
sensu stricto group) from tree bark. The employment of two temperatures (10°C in addition to the more commonly used 30°C) resulted in the isolation of
S. kudriavzevii
and
S. uvarum
, two species that grow at low temperatures, in addition to
S. cerevisiae
and
S. paradoxus
. A clear bias was found toward the bark of certain trees, particularly certain oak species. Very often, more than one
Saccharomyces
species was found in one locality and occasionally even in the same bark sample. Our evidence strongly suggests that (markedly) different growth temperature preferences play a fundamental role in the sympatric associations of
Saccharomyces
species uncovered in this survey.
S. kudriavzevii
was isolated at most of the sites sampled in Portugal, indicating that the geographic distribution of this species is wider than the distribution assumed thus far. However, the Portuguese
S. kudriavzevii
population exhibited important genetic differences compared to the type strain of the species that represents a Japanese population. In this study,
S. kudriavzevii
stands out as the species that copes better with low temperatures.
Traceability of Asian
Matsutake
, Specialty Mushrooms Produced by the Ectomycorrhizal Basidiomycete
Tricholoma matsutake
, on the Basis of Retroelement-Based DNA Markers
Authors: Murata Hitoshi , Babasaki Katsuhiko , Saegusa Tomoki , Takemoto Kenji , Yamada Akiyoshi , Ohta Akira
Published: February 2008

The ectomycorrhizal basidiomycete
Tricholoma matsutake
produces commercially valuable fruit bodies,
matsutake
, in forests. Here we report a PCR system targeting retroelement integration sites to differentiate among individual Asian isolates of
T. matsutake
based on their geographical origins, such as Japan, the area of South Korea through North Korea, the northeastern provinces of China, and the area of the southwestern provinces of China through Bhutan. The overall misjudgment rate of the analytical system was approximately 5% based on 95 samples of
T. matsutake
examined including those from cultures and from commodities. We also provide evidence that
T. matsutake
isolates grown throughout the Far East, including the northeastern provinces of China, are closely related to each other while distinct from those in the area of the southwestern provinces of China through Bhutan. The method allows us to trace back geographical origins of Asian
matsutake
, thus contributing to food safety, appropriate tariffs, and proper price setting.
Evidence of a Continuous Endoplasmic Reticulum in the Protozoan Parasite
Entamoeba histolytica
Authors: Teixeira Jose E. , Huston Christopher D.
Published: February 2008

Entamoeba histolytica
, the cause of amebiasis, is believed to have no continuous endoplasmic reticulum (ER), with ER functions occurring in vesicles. Here, using an ER-targeted green fluorescent protein fusion protein and fluorescence loss in photobleaching, we have unambiguously demonstrated the presence of a continuous ER compartment in living
E. histolytica
trophozoites.
Evidence of Recombination in Mixed-Mating-Type and α-Only Populations of
Cryptococcus gattii
Sourced from Single
Eucalyptus
Tree Hollows
Authors: Saul Nathan , Krockenberger Mark , Carter Dee
Published: February 2008

Disease caused by the pathogenic yeast
Cryptococcus gattii
begins with the inhalation of an infectious propagule. As
C. gattii
is heavily encapsulated, this propagule is most likely to be a basidiospore. However, most
C. gattii
strains are infertile in laboratory crosses, and population studies indicate that recombination and dispersal are very restricted. In addition, strains of the α mating type predominate, which would not be expected in a mating population.
C. gattii
comprises four genetically distinct molecular genotypes, designated VGI to VGIV.
C. gattii
molecular type VGI has a strong association with
Eucalyptus camaldulensis
and can be found in high numbers in
E. camaldulensis
hollows. Previous work on isolates obtained from
E. camaldulensis
suggested that environmental populations of
C. gattii
are highly fragmented, have limited ability to disperse, and are confined to individual tree hollows. In the current study, we examined large numbers of isolates from three separate hollows for evidence of recombination. In two hollows, the α and
a
mating types were present in approximately equal numbers. The third hollow had α cells only and was from a region where
a
isolates have never been found. Statistical analysis of multilocus genotypes revealed recombining subpopulations in the three
Eucalyptus
hollows. Recombination was equally present in the α-
a
and α-only populations. This is consistent with recent studies that have found evidence suggestive of α-α mating in
C. gattii
and
Cryptococcus neoformans
and raises the possibility this may be a widespread phenomenon, allowing these fungi to recombine despite a paucity of
a
mating partners.
Molecular and Biochemical Characterization of a Cathepsin B-Like Protease Family Unique toTrypanosoma congolense
Authors: Mendoza-Palomares Carlos , Biteau Nicolas , Giroud Christiane , Coustou Virginie , Coetzer Theresa , Authié Edith , Boulangé Alain , Baltz Théo
Published: February 2008

Cysteine proteases have been shown to be essential virulence factors and drug targets in trypanosomatids and an attractive antidisease vaccine candidate forTrypanosoma congolense. Here, we describe an important amplification of genes encoding cathepsin B-like proteases unique toT. congolense. More than 13 different genes were identified, whereas only one or two highly homologous genes have been identified in other trypanosomatids. These proteases grouped into three evolutionary clusters: TcoCBc1 to TcoCBc5 and TcoCBc6, which possess the classical catalytic triad (Cys, His, and Asn), and TcoCBs7 to TcoCBs13, which contains an unusual catalytic site (Ser, Xaa, and Asn). Expression profiles showed that members of the TcoCBc1 to TcoCBc5 and the TcoCBs7 to TcoCBs13 groups are expressed mainly in bloodstream forms and localize in the lysosomal compartment. The expression of recombinant representatives of each group (TcoCB1, TcoCB6, and TcoCB12) as proenzymes showed that TcoCBc1 and TcoCBc6 are able to autocatalyze their maturation 21 and 31 residues, respectively, upstream of the predicted start of the catalytic domain. Both displayed a carboxydipeptidase function, while only TcoCBc1 behaved as an endopeptidase. TcoCBc1 exhibited biochemical differences regarding inhibitor sensitivity compared to that of other cathepsin B-like proteases. Recombinant pro-TcoCBs12 did not automature in vitro, and the pepsin-matured enzyme was inactive in tests with cathepsin B fluorogenic substrates. In vivo inhibition studies using CA074Me (a cell-permeable cathepsin B-specific inhibitor) demonstrated that TcoCB are involved in lysosomal protein degradation essential for survival in bloodstream form. Furthermore, TcoCBc1 elicited an important immune response in experimentally infected cattle. We propose this family of proteins as a potential therapeutic target and as a plausible antigen forT. congolensediagnosis.
An Internal Polarity Landmark Is Important for Externally Induced Hyphal Behaviors in
Candida albicans
Authors: Brand Alexandra , Vacharaksa Anjalee , Bendel Catherine , Norton Jennifer , Haynes Paula , Henry-Stanley Michelle , Wells Carol , Ross Karen , Gow Neil A. R. , Gale Cheryl A.
Published: February 2008

Directional growth is a function of polarized cells such as neurites, pollen tubes, and fungal hyphae. Correct orientation of the extending cell tip depends on signaling pathways and effectors that mediate asymmetric responses to specific environmental cues. In the hyphal form of the eukaryotic fungal pathogen
Candida albicans
, these responses include thigmotropism and galvanotropism (hyphal turning in response to changes in substrate topography and imposed electrical fields, respectively) and penetration into semisolid substrates. During vegetative growth in
C. albicans
, as in the model yeast
Saccharomyces cerevisiae
, the Ras-like GTPase Rsr1 mediates internal cellular cues to position new buds in a prespecified pattern on the mother cell cortex. Here, we demonstrate that Rsr1 is also important for hyphal tip orientation in response to the external environmental cues that induce thigmotropic and galvanotropic growth. In addition, Rsr1 is involved in hyphal interactions with epithelial cells in vitro and its deletion diminishes the hyphal invasion of kidney tissue during systemic infection. Thus, Rsr1, an internal polarity landmark in yeast, is also involved in polarized growth responses to asymmetric environmental signals, a paradigm that is different from that described for the homologous protein in
S. cerevisiae
. Rsr1 may thereby contribute to the pathogenesis of
C. albicans
infections by influencing hyphal tip responses triggered by interaction with host tissues.
Histone H1 of
Trypanosoma cruzi
Is Concentrated in the Nucleolus Region and Disperses upon Phosphorylation during Progression to Mitosis
Authors: Gutiyama Luciana M. , da Cunha Julia P. Chagas , Schenkman Sergio
Published: February 2008

Phosphorylation of histone H1 is intimately related to the cell cycle progression in higher eukaryotes, reaching maximum levels during mitosis. We have previously shown that in the flagellated protozoan
Trypanosoma cruzi
, which does not condense chromatin during mitosis, histone H1 is phosphorylated at a single cyclin-dependent kinase site. By using an antibody that recognizes specifically the phosphorylated
T. cruzi
histone H1 site, we have now confirmed that
T. cruzi
histone H1 is also phosphorylated in a cell cycle-dependent manner. Differently from core histones, the bulk of nonphosphorylated histone H1 in G
1
and S phases of the cell cycle is concentrated in the central regions of the nucleus, which contains the nucleolus and less densely packed chromatin. When cells pass G
2
, histone H1 becomes phosphorylated and starts to diffuse. At the onset of mitosis, histone H1 phosphorylation is maximal and found in the entire nuclear space. As permeabilized parasites preferentially lose phosphorylated histone H1, we conclude that this modification promotes its release from less condensed and nucleolar chromatin after G
2
.
Lineage-Specific Amino Acid Substitutions in Region 2 of the RNA Polymerase σ Subunit Affect the Temperature of Promoter Opening
Authors: Barinova N. , Zhilina E. , Bass I. , Nikiforov V. , Kulbachinskiy A.
Published: February 2008

Highly conserved amino acid residues in region 2 of the RNA polymerase σ subunit are known to participate in promoter recognition and opening. We demonstrated that nonconserved residues in this region collectively determine lineage-specific differences in the temperature of promoter opening.
Determination of Molecular Phylogenetics of
Vibrio parahaemolyticus
Strains by Multilocus Sequence Typing
Authors: González-Escalona Narjol , Martinez-Urtaza Jaime , Romero Jaime , Espejo Romilio T. , Jaykus Lee-Ann , DePaola Angelo
Published: February 2008

Vibrio parahaemolyticus
is an important human pathogen whose transmission is associated with the consumption of contaminated seafood. There is a growing public health concern due to the emergence of a pandemic strain causing severe outbreaks worldwide. Many questions remain unanswered regarding the evolution and population structure of
V. parahaemolyticus
. In this work, we describe a multilocus sequence typing (MLST) scheme for
V. parahaemolyticus
based on the internal fragment sequences of seven housekeeping genes. This MLST scheme was applied to 100
V. parahaemolyticus
strains isolated from geographically diverse clinical (
n
= 37) and environmental (
n
= 63) sources. The sequences obtained from this work were deposited and are available in a public database (
http://pubmlst.org/vparahaemolyticus
). Sixty-two unique sequence types were identified, and most (50) were represented by a single isolate, suggesting a high level of genetic diversity. Three major clonal complexes were identified by eBURST analysis. Separate clonal complexes were observed for
V. parahaemolyticus
isolates originating from the Pacific and Gulf coasts of the United States, while a third clonal complex consisted of strains belonging to the pandemic clonal complex with worldwide distribution. The data reported in this study indicate that
V. parahaemolyticus
is genetically diverse with a semiclonal population structure and an epidemic structure similar to that of
Vibrio cholerae
. Genetic diversity in
V. parahaemolyticus
appears to be driven primarily by frequent recombination rather than mutation, with recombination ratios estimated at 2.5:1 and 8.8:1 by allele and site, respectively. Application of this MLST scheme to more
V. parahaemolyticus
strains and by different laboratories will facilitate production of a global picture of the epidemiology and evolution of this pathogen.
Complete Genome Sequence ofLeuconostoc citreumKM20
Authors: Kim Jihyun F. , Jeong Haeyoung , Lee Jung-Sook , Choi Sang-Haeng , Ha Misook , Hur Cheol-Goo , Kim Ji-Sun , Lee Soohyun , Park Hong-Seog , Park Yong-Ha , Oh Tae Kwang
Published: February 2008

Leuconostoc citreumis one of the most prevalent lactic acid bacteria during the manufacturing process of kimchi, the best-known Korean traditional dish. We have determined the complete genome sequence ofL. citreumKM20. It consists of a 1.80-Mb chromosome and four circular plasmids and reveals genes likely involved in kimchi fermentation and its probiotic effects.
An Extracellular Glycoprotein Is Implicated in Cell-Cell Contacts in the Toxic CyanobacteriumMicrocystis aeruginosaPCC 7806
Authors: Zilliges Yvonne , Kehr Jan-Christoph , Mikkat Stefan , Bouchier Christiane , de Marsac Nicole Tandeau , Börner Thomas , Dittmann Elke
Published: February 2008

Microcystins are the most common cyanobacterial toxins found in freshwater lakes and reservoirs throughout the world. They are frequently produced by the unicellular, colonial cyanobacteriumMicrocystis aeruginosa; however, the role of the peptide for the producing organism is poorly understood. Differences in the cellular aggregation ofM. aeruginosaPCC 7806 and a microcystin-deficient ΔmcyBmutant guided the discovery of a surface-exposed protein that shows increased abundance in PCC 7806 mutants deficient in microcystin production compared to the abundance of this protein in the wild type. Mass spectrometric and immunoblot analyses revealed that the protein, designated microcystin-related protein C (MrpC), is posttranslationally glycosylated, suggesting that it may be a potential target of a putative O-glycosyltransferase of the SPINDLY family encoded downstream of themrpCgene. Immunofluorescence microscopy detected MrpC at the cell surface, suggesting an involvement of the protein in cellular interactions in strain PCC 7806. Further analyses of field samples ofMicrocystisdemonstrated a strain-specific occurrence of MrpC possibly associated with distinctMicrocystiscolony types. Our results support the implication of microcystin in the colony specificity of and colony formation byMicrocystis.
The Iron-Responsive Fur Regulon in
Yersinia pestis
Authors: Gao He , Zhou Dongsheng , Li Yingli , Guo Zhaobiao , Han Yanping , Song Yajun , Zhai Junhui , Du Zongmin , Wang Xiaoyi , Lu Jingmei , Yang Ruifu
Published: February 2008

The ferric uptake regulator (Fur) is a predominant bacterial regulator controlling the iron assimilation functions in response to iron availability. Our previous microarray analysis on
Yersinia pestis
defined the iron-Fur modulon. In the present work, we reannotated the iron assimilation genes in
Y. pestis
, and the resulting genes in complementation with those disclosed by microarray constituted a total of 34 genome loci (putative operons) that represent the potential iron-responsive targets of Fur. The subsequent real-time reverse transcription-PCR (RT-PCR) in conjunction with the primer extension analysis showed that 32 of them were regulated by Fur in response to iron starvation. A previously predicted Fur box sequence was then used to search against the promoter regions of the 34 operons; the homologue of the above box could be predicted in each promoter tested. The subsequent electrophoretic mobility shift assay (EMSA) demonstrated that a purified His
6
tag-fused Fur protein was able to bind in vitro to each of these promoter regions. Therefore, Fur is a global regulator, both an activator and a repressor, and directly controls not only almost all of the iron assimilation functions but also a variety of genes involved in various non-iron functions for governing a complex regulatory cascade in
Y. pestis
. In addition, real-time RT-PCR, primer extension, EMSA, and DNase I footprinting assay were used to elucidate the Fur regulation of the
ybt
locus encoding a virulence-required iron uptake system. By combining the published data on the YbtA regulation of
ybt
, we constructed a concise Fur/YbtA regulatory network with a map of the Fur-promoter DNA interactions within the
ybt
locus. The data presented here give us an overview of the iron-responsive Fur regulon in
Y. pestis
.
Myofilament mechanical performance is enhanced by R403Q myosin in mouse myocardium independent of sex
Authors: Palmer Bradley M. , Wang Yuan , Teekakirikul Polakit , Hinson J. Travis , Fatkin Diane , Strouse Stacy , VanBuren Peter , Seidman Christine E. , Seidman J. G. , Maughan David W.
Published: February 2008

Male but not female mice carrying a single R403Q missense allele for cardiac α-myosin heavy chain (M-αMHCR403Q/+and F-αMHCR403Q/+, respectively) develop significant hypertrophic cardiomyopathy (HCM) compared with male and female wild-type mice (M-αMHC+/+and F-αMHC+/+, respectively) after ∼30 wk of age. We tested the hypothesis that myofilament mechanical performance differs between M-αMHCR403Q/+and F-αMHCR403Q/+at younger ages (10–20 wk) and could account for sex differences in HCM development. The sensitivity of chemically skinned myocardial strips to Ca2+activation (pCa50) was significantly ( P < 0.05) enhanced in male mice independent of genotype (M-αMHCR403Q/+: 5.70 ± 0.06, M-αMHC+/+: 5.63 ± 0.05, F-αMHCR403Q/+: 5.57 ± 0.03, F-αMHC+/+: 5.54 ± 0.04) by two-way ANOVA, whereas maximum developed tension was significantly enhanced in α-MHCR403Q/+independent of sex (M-αMHCR403Q/+: 29.3 ± 2.3, M-αMHC+/+: 26.0 ± 1.4, F-αMHCR403Q/+: 30.2 ± 2.1, F-αMHC+/+: 26.2 ± 1.2 mN/mm2). The frequency of maximum work generated by sinusoidal length perturbation was significantly higher in αMHCR403Q/+mice than in sex-matched controls (M-αMHCR403Q/+: 2.26 ± 0.47, M-αMHC+/+: 1.29 ± 0.18, F-αMHCR403Q/+: 3.21 ± 0.33, F-αMHC+/+: 2.52 ± 0.36 Hz). Unloaded shortening velocity was significantly enhanced in αMHCR403Q/+and in female mice (M-αMHCR403Q/+: 2.26 ± 0.47, M-αMHC+/+: 1.29 ± 0.18, F-αMHCR403Q/+: 3.21 ± 0.33, F-αMHC+/+: 2.52 ± 0.36 muscle lengths/s), and normalized mechanical power, calculated from the tension-velocity relationship, was significantly enhanced in αMHCR403Q/+independent of sex (M-αMHCR403Q/+: 60 ± 2 10−3, M-αMHC+/+: 37 ± 3 10−3, F-αMHCR403Q/+: 57 ± 3 10−3, F-αMHC+/+25 ± 3 10−3muscle lengths/s × normalized tension). We did not find a statistically significant sex × mutation interaction for any measure of myofilament performance. Therefore, sarcomeric incorporation of the R403Q myosin similarly enhanced left ventricular myofilament mechanical performance in both male and female mice. The sex-dependent development of HCM due to the R403Q myosin may then be inhibited by female sex hormones, which may additionally underlie the observed sex differences for pCa50and unloaded shortening velocity.
Deficiency of mitogen-activated protein kinase phosphatase-1 results in iNOS-mediated hypotension in response to low-dose endotoxin
Authors: Calvert Thomas J. , Chicoine Louis G. , Liu Yusen , Nelin Leif D.
Published: February 2008

Mitogen-activated protein kinase phosphatase-1 (MKP-1) is essential in limiting the proinflammatory response to lipopolysaccharide (LPS). We hypothesized that Mkp-1−/− mice would respond to low-dose LPS with a fall in blood pressure due to augmented expression of inducible nitric oxide (NO) synthase (iNOS). To test this hypothesis, Mkp-1−/− mice and their wild-type littermates were treated with 10 μg/kg iv LPS, and mean arterial blood pressure (MAP) and exhaled NO production (exNO) were measured. Tissues were harvested for an assessment of iNOS protein levels. Wild-type mice had no change in MAP or exNO during the experimental period, whereas Mkp-1−/− mice had a fall ( P < 0.005) in MAP [79 ± 5% of baseline (BL)] and an increase ( P < 0.01) in exNO (266 ± 50% of BL) after 150 min. The tissue levels of iNOS were greater in Mkp-1−/− than in wild-type mice. In additional experiments, 60 min after LPS treatment, Mkp-1−/− and wild-type mice were given Nω-nitro-l-arginine methyl ester (l-NAME) or aminoguanidine, and MAP and exNO were monitored for 90 min. Treatment with l-NAME prevented the LPS-induced increase in exNO and decrease in MAP but resulted in decreased exNO and elevated MAP in wild-type mice. Aminoguanidine prevented the increase in exNO and the fall in MAP caused by LPS in Mkp-1−/− mice, without significantly affecting MAP or exNO in wild-type mice. These results demonstrate that a deficiency of MKP-1 results in an exaggerated hypotensive response to LPS mediated by augmented iNOS expression. We speculate that defects in the Mkp-1 gene may increase susceptibility for the development of septic shock.
Effect of endothelin receptor antagonists on ventricular susceptibility in postinfarcted rats
Authors: Lee Tsung-Ming , Chen Chien-Chang , Lin Mei-Shu , Chang Nen-Chung
Published: February 2008

This study investigated whether selective endothelin (ET) type A (ETA) or nonselective ETA/ETB receptor blockade exerted antiarrhythmic effects through attenuated sympathetic reinnervation after infarction. Twenty-four hours after ligation of the left anterior descending artery, male Wistar rats received either vehicle, ABT-627 (selective ETA receptor antagonist), bosentan (nonselective ETA/ETB receptor antagonist), or hydralazine for 4 wk. The measurement of myocardial ET-1 levels at the remote zone revealed a significant increase in vehicle-treated infarcted rats compared with sham-operated rats, consistent with increased activities of ET-1 after infarction. Sympathetic nerve function changes assessed by the norepinephrine content of myocardium and the dialysate and plasma dihydroxyphenylglycol levels were parallel to ET-1 levels. Immunohistochemical analysis for tyrosine hydroxylase, growth-associated protein 43, and neurofilament also confirmed the change of nerve function. This was accompanied with a significant upregulation of nerve growth factor protein expression and mRNA in the vehicle-treated infarcted rats, which reduced after the administration of either ETA or ETA/ETB blockade to a similar extent. The beneficial effects of ET receptor antagonists on sympathetic nerve function and structures were dissociated from their blood pressure-lowering effect because ET receptor antagonists and hydralazine reduced arterial pressure similarly. Arrhythmic severity during programmed stimulation in ET receptor antagonists-treated rats was significantly lower than that in vehicle-treated infarcted rats. Our data indicate that the ET system, especially via ETA receptors, plays an important role in attenuating sympathetic reinnervation after infarction. Independent of their hemodynamic effects, a chronic use of either ETA or ETA/ETB antagonists may modify the arrhythmogenic response to programmed electrical stimulation.
Disparate mechanisms of sICAM-1 production in the peripheral lung: contrast between alveolar epithelial cells and pulmonary microvascular endothelial cells
Authors: Mendez Michael P. , Morris Susan B. , Wilcoxen Steven , Du Ming , Monroy Yeni K. , Remmer Henriette , Murphy Hedwig , Christensen Paul J. , Paine Robert
Published: February 2008

Membrane-associated intercellular adhesion molecule-1 (mICAM-1; CD54) is constitutively expressed on the surface of type I alveolar epithelial cells (AEC). Soluble ICAM-1 (sICAM-1) may be produced by proteolytic cleavage of mICAM-1 or by alternative splicing of ICAM-1 mRNA. In contrast to inducible expression seen in most cell types, sICAM-1 is constitutively released by type I AEC and is present in normal alveolar lining fluid. Therefore, we compared the mechanism of sICAM-1 production in primary cultures of two closely juxtaposed cells in the alveolar wall, AEC and pulmonary microvascular endothelial cells (PVEC). AEC, but not PVEC, demonstrated high-level baseline expression of sICAM-1. Stimulation of AEC with TNFα or LPS resulted in minimal increase in AEC sICAM-1, whereas PVEC sICAM-1 was briskly induced in response to these signals. AEC sICAM-1 shedding was significantly reduced by treatment with a serine protease inhibitor, but not by cysteine, metalloprotease, or aspartic protease inhibitors. In contrast, none of these inhibitors effected sICAM-1 expression in PVEC. RT-PCR, followed by gel analysis of total RNA, suggests that alternatively spliced fragments are present in both cell types. However, a 16-mer oligopeptide corresponding to the juxtamembrane region of mICAM-1 completely abrogated sICAM-1 shedding in AEC but reduced stimulated PVEC sICAM-1 release by only 20%. Based on these data, we conclude that the predominant mechanism of sICAM-1 production likely differs in the two cell types from opposite sides of the alveolar wall.
Role of vasodilator-stimulated phosphoprotein in cGMP-mediated protection of human pulmonary artery endothelial barrier function
Authors: Rentsendorj Otgonchimeg , Mirzapoiazova Tamara , Adyshev Djanybek , Servinsky Laura E. , Renné Thomas , Verin Alexander D. , Pearse David B.
Published: February 2008

Increased pulmonary endothelial cGMP was shown to prevent endothelial barrier dysfunction through activation of protein kinase G (PKGI). Vasodilator-stimulated phosphoprotein (VASP) has been hypothesized to mediate PKGIbarrier protection because VASP is a cytoskeletal phosphorylation target of PKGIexpressed in cell-cell junctions. Unphosphorylated VASP was proposed to increase paracellular permeability through actin polymerization and stress fiber bundling, a process inhibited by PKGI-mediated phosphorylation of Ser157and Ser239. To test this hypothesis, we examined the role of VASP in the transient barrier dysfunction caused by H2O2in human pulmonary artery endothelial cell (HPAEC) monolayers studied without and with PKGIexpression introduced by adenoviral infection (Ad.PKG). In the absence of PKGIexpression, H2O2(100–250 μM) caused a transient increased permeability and pSer157-VASP formation that were both attenuated by protein kinase C inhibition. Potentiation of VASP Ser157phosphorylation by either phosphatase 2B inhibition with cyclosporin or protein kinase A activation with forskolin prolonged, rather than inhibited, the increased permeability caused by H2O2. With Ad.PKG infection, inhibition of VASP expression with small interfering RNA exacerbated H2O2-induced barrier dysfunction but had no effect on cGMP-mediated barrier protection. In addition, expression of a Ser-double phosphomimetic mutant VASP failed to reproduce the protective effects of activated PKGI. Finally, expression of a Ser-double phosphorylation-resistant VASP failed to interfere with the ability of cGMP/PKGIto attenuate H2O2-induced disruption of VE-cadherin homotypic binding. Our results suggest that VASP phosphorylation does not explain the protective effect of cGMP/PKGIon H2O2-induced endothelial barrier dysfunction in HPAEC.
Freedom of Expression on the Internet: A Case Study of Uzbekistan
Authors: Kozhamberdiyeva Zhanna
Published: February 2008

Against the framework of international human rights law, this article studies the regulatory approach towards the exercise of the human right to freedom of expression on the Internet in the legal system of the Central Asian state of Uzbekistan. The mechanisms of state censorship of Internet communication for Uzbek citizens and the restrictions that narrow the scope of freedom of expression in the context of the Internet are the issues in focus. The article argues that the Uzbek government, although publicly committed to democracy and respect for the rule of law under the Constitution, favors regulation that undermines the human right to freedom of expression on both legal and ideological grounds—namely, by enforcing the legal rules on information security and the ideological 'idea of national independence'. The article demonstrates that the absence of legal guarantees of the effective exercise of freedom of expression on the Internet reflects upon the general weakness of Uzbekistan's domestic system of human rights protection. This system gives absolute priority to state interests in legitimizing restrictions upon human rights. The article concludes that the impairment of the right to freedom of expression is inevitable in Uzbekistan unless the government makes an effort to pay full respect to human rights and implement in practice its obligations under international human rights law.
The 'Anti-Manichaean' Passage in Confessions 3 and its 'Manichaean Audience'
Authors: Kotzé Annemaré
Published: February 2008

The article is an analysis of Confessions 3.6.10 to 3.10.18 to support an argument that many strategies in Augustine's masterpiece are eminently suited to communicate with a Manichaean audience and designed to convince such an audience of the errors of Manichaeism. In Book 3 the narrative reaches the stage of Augustine's life where he joins the Manichees. The description of the encounter presented here, however, is much more than the communication of information on this crucial stage in his spiritual journey. The passage is generally described as strongly anti-Manichaean, but I argue that the argumentative and emotional tone of the passage combined with the amount of space spent on a few core aspects of Manichaeism make the passage an effective protreptic directed at a specific category of 'Manichaean' readers.
Impatience and Humanity's Sinful State in Tertullian of Carthage
Authors:   Steenberg
Published: February 2008

Tertullian's unique use of 'patience' as a salvific paradigm, grounds a conception of human nature, and particularly sin and 'fallen nature', articulated in economic terms. This article takes this conception, together with Tertullian's bipartite anthropology, to disclose a unique understanding of humanity's sinful condition. As the two composite 'parts' of man art interrelated in an economy of relation to God, so we will argue Tertullian grounds his concept of soteriology in his vision of the human person, linking it intrinsically to the life of Christ and the offering of the cross, uniting the human to the trinitarian life of Father, Son and Spirit.
Effect of Food, Type of Food, and Time of Food Intake on Deferasirox Bioavailability: Recommendations for an Optimal Deferasirox Administration Regimen
Authors: Galanello Renzo , Piga Antonio , Cappellini Maria Domenica , Forni Gian Luca , Zappu Antonella , Origa Raffaella , Dutreix Catherine , Belleli Rossella , Ford John M. , Rivière Gilles‐Jacques , Balez Sébastien , Alberti Daniele , Séchaud Romain
Published: February 2008

Deferasirox (ICL670) is representative of a new class of tridentate iron chelators, formulated as tablets for dispersion. Deferasirox has exhibited high potency and a clinically manageable safety profile in preclinical models and in an extensive clinical program. The effect of food and time of food intake on the pharmacokinetics of deferasirox was investigated in healthy volunteers and patients with transfusional hemosiderosis. The bioequivalence of a single oral dose of deferasirox (20 mg/kg) was assessed following administration either before a high‐fat or standard breakfast or concurrent with a standard breakfast in comparison with fasted conditions in healthy volunteers. The bioavailability of deferasirox was determined following a single oral dose (20 mg/kg) under fed and fasted conditions in patients. These data show that the type of food, caloric content, and fat content of the meal influence the bioavailability of deferasirox when consumed concomitantly. In contrast, this is not the case when deferasirox is administered at least 30 minutes before a meal. In conclusion, it is recommended that deferasirox be administered at least 30 minutes prior to meals. When this is not feasible, deferasirox should be administered consistently at the same time before meals to limit the sources of variability that affect absorption.
Self-Objectification and Well-Being in Women's Daily Lives
Authors: Breines Juliana G. , Crocker Jennifer , Garcia Julie A.
Published: February 2008

Laboratory experiments and surveys show that self-objectification increases body shame, disrupts attention, and negatively predicts well-being. Using experience sampling methodology, the authors investigated self-objectification in the daily lives of 49 female college students. Building on the predictions of objectification theory, they examined associations between internalizing an observer's perspective on the self and psychological well-being, and examined the moderating roles of trait self-esteem and appearance-contingent self-worth. Within-person increases in self-objectification predicted decreased well-being, but this association was moderated by trait self-esteem and trait appearance-contingent self-worth; high self-esteem, highly appearance-contingent participants reported increased well-being when they self-objectified. Furthermore, perceived unattractiveness partially mediated the main effect and the three-way interaction: high self-esteem, highly contingent participants experienced smaller drops in well-being when they self-objectified, in part because they felt less unattractive. These results suggest that in daily life, some women receive a boost from self-objectification, although most women experience decreases in well-being when self-objectifying.
Commingled Samples: A Neglected Source of Bias in Reliability Analysis
Authors: Waller Niels G.
Published: February 2008

Reliability is a property of test scores from individuals who have been sampled from a well-defined population. Reliability indices, such as coefficient α and related formulas for internal consistency reliability (KR-20, Hoyt's reliability), yield lower bound reliability estimates when (a) subjects have been sampled from a single population and when (b) test items are congeneric (i.e., when items are sampled from a single latent dimension). However, when samples are commingled—that is, when they are composed of scores that are drawn from multiple populations— coefficient α and related indices can be severely biased. In most cases the bias inflates α; in other cases α is attenuated. Equations are derived for elucidating this bias in two-group mixture distributions.
Evaluation of the Persistently Violent Offender Treatment Program
Authors: Serin Ralph C. , Gobeil Renée , Preston Denise L.
Published: February 2008

The treatment of violent offenders has evolved in recent years, shifting from interventions focused on anger management to those incorporating social information processing skills. The present study was a multimethod evaluation of one such program, the Persistently Violent Offender program. A total of 256 Canadian male violent offenders participated in the study; 70 Persistently Violent Offender program completers were compared to two control groups ( n1 = 33, n2 = 105) who completed an alternate program and to 48 offenders who failed to complete either program. Results demonstrate few differences among groups in terms of changes on measures of treatment targets, involvement in institutional misconducts, and postrelease returns to custody, thus demonstrating that the Persistently Violent Offender program was superior to neither the alternate program nor program noncompletion. These results are discussed in light of the findings from two more promising recent evaluations of similar programs.
Can We Identify Predictors of Multilevel Botulinum Toxin A Injections in Children With Cerebral Palsy Who Walk With a Flexed Knee Pattern?
Authors: Scholtes Vanessa A. , Dallmeijer Annet J. , Becher Jules G.
Published: February 2008

This study evaluates whether the literature-reported potential predictors can predict the outcome of multilevel botulinum toxin A injections in children who walk with flexed knees. The associations between 11 different predictors and 2 different outcome measures (the Gross Motor Function Measure and knee angle at midstance) at different weeks of follow-up were studied in 46 children with cerebral palsy (age 4–12 years), using regression analysis. Only age was positively associated with change in the Gross Motor Function Measure at 12 weeks, and only ankle angle at midstance was positively associated with change in knee angle at midstance at 48 weeks. Of these, only the former association was found to be clinically relevant. Conclusion: the majority of potential predictors do not predict the outcome of multilevel botulinum toxin A injections in this patient group. The only relevant significant predictor, with regard to gross motor function, is older age.
Timing of Neonatal Seizures and Intrapartum Obstetrical Factors
Authors: Scher Mark S. , Steppe Doris A. , Beggarly Marquita
Published: February 2008

One hundred ninety-three neonates with seizures were available on a neonatal seizure database, which included intrapartum and neonatal factors such as labor duration, fetal heart rate abnormalities, cord blood gas values, Apgar scores and clinical signs of encephalopathy. Regression analyses (analysis of variance) were performed on the entire cohort as well as specific subsets of neonates (eg, neonatal encephalopathy vs no encephalopathy) to assess the relationship between seizure timing and intrapartum/neonatal factors. Seizures were noted earlier for the encephalopathic group than for the nonencephalopathic group. No significant differences were noted for any intrapartum or neonatal factors. Timing of neonatal seizures, with or without an encephalopathy occurs within the first 2 days after birth and is independent of selected intrapartum and neonatal factors, underscoring recent task force recommendations concerning neonatal encephalopathy. Factors other than intrapartum events more likely contribute to the encephalopathic repertoire of the newborn, including seizures.
Single-Walled Carbon Nanotubes — Ionic Polymer Electroactive Hybrid Transducers
Authors: Akle Barbar J. , Leo Donald J.
Published: February 2008

Ionic electroactive polymers, sometimes referred to as artificial muscles, have the ability to generate large bending strain and moderate stress at low applied voltages. Typical types of ionic electroactive polymer transducers include ionic polymers, conducting polymers, and carbon nanotubes. Preliminary research combining multiple types of materials proved to enhance certain transduction properties. Bennett and Leo (Materials Research Society Symposium Proceedings, vol. 785, 2003b) showed that the speed of response, maximum strain, and quasi-static actuation are improved by adding a layer of conducting polymer on an ionic polymer transducer. In this work, a recently developed fabrication method called the direct assembly process (DAP) plating is used to build SWNT/RuO2 hybrid transducers. The DAP consists of mixing a conducting powder with an ionomer solution. This technique has demonstrated improved response time and strain output as compared to previous methods. Electrodes applied using this new technique of mixing RuO2 (surface area 45—65 m2/g) particles and NafionTMdispersion provided 5× the displacement and 10× the force compared to a transducer made with conventional methods. Furthermore, previous studies demonstrated that the response speed of the transducer is optimized by varying the composition of metal in the electrode (Akle, B.J., Bennett, M.D., Leo, D.J., Wiles, K.B. and McGrath, J.E. 2007. "Direct Assembly Process: A Novel Fabrication Technique for Large Strain Ionic Polymer Transducers,'' Journal of Mat. Sci., 42:7031—7041). For RuO2, the optimal loading was approximately 45vol%, while carbon nanotubes electrodes have an optimal performance at 30vol%. Due to low percolation threshold, carbon nanotubes actuators perform better at a lower loading compared to other conducting powders. The addition of single-walled carbon nanotubes (SWNT) to the electrode increases both the strain rate and the maximum strain of the hybrid actuator. The strain rate of the transducer increased proportional to the ratio of SWNT to RuO2 in the electrode. A maximum peak-to-peak strain of 10.6% (±2V) is attained in a 15vol% SWNT/30 vol% RuO2 hybrid transducer. The maximum strain rate of 2.7%/s is generated by a 20vol% SWNT/25 vol% RuO2 hybrid transducer.
A Theoretical Model of Conductive Cracks in Piezoelectric Materials under Electromechanical Cycling
Authors: Wang B.-L. , Sun Y.-G.
Published: February 2008

This article develops an analytical model for the conductive cracks in piezoelectric ceramics under electromechanical cycling. An electrical yielding strip and a mechanical yielding strip are assumed to develop at the crack tips when the medium is subjected to external electromechanical loads. The yielding strip is assumed to have constant stress and constant electric field. Based on these assumptions and extending the accumulated plastic displacement criterion for crack propagation in traditional structural materials to piezoelectric ceramics, a fatigue crack growth law is derived. The law, similar to the well known Paris law, is a fourth-power function of the effective stress intensity factor. Graphical results for the effect of electric load on the effective crack tip stress intensity factor and crack growth rate are provided. The law is given in closed-form so that it might be used in the future for the fatigue and reliability analysis and design of piezoelectric materials.
Concept and Electro-elastic Modeling of Shear Actuated Fiber Composite using Micro-mechanics Approach
Authors: Raja S. , Ikeda Tadashige
Published: February 2008

A Shear Actuated Fiber Composite (SAFC) concept is developed that may find application in structural actuation and health monitoring tasks. The fabrication aspects of SAFC are briefly discussed. A uniform field model is employed to study electro-elastic behavior of the SAFC. The composite actuator is modeled as a general laminate having seven layers, and the effective properties are evaluated further using shear deformation lamination theory. The geometric parameters such as fiber volume fraction, fiber thickness, and fiber orientation are considered, and their influence on the characteristics of SAFC is analyzed. It is observed that a higher fiber thickness may provide better shear actuation capability for the SAFC actuator; but conformability requirements bring a constraint on fiber thickness that needs to be optimized. A fiber volume content of 85—95% appears to provide a design envelope for the SAFC actuator. SAFC has shown a promising feature of simultaneously coupling both transverse shear strains, if the poled PZT fibers are oriented directionally. Therefore, SAFC can be used as a torsional actuator for developing electro-elastically tailored smart laminated or sandwich structures. It is also expected that the SAFC actuator may provide a better solution for active aeroelastic control applications, where torsion mode is critical.
Characteristics of an Insect-mimicking Flapping System Actuated by a Unimorph Piezoceramic Actuator
Authors: Nguyen Viet-Quoc , Syaifuddin M. , Park H.C. , Byun D.Y. , Goo N.S. , Yoon K.J.
Published: February 2008

This study introduces an insect-mimicking flapping-wing system, where the rotation, corrugation, and clapping of insect wings have been mimicked. Unlike most motor-driven flapping systems, the flapping in this system is actuated by a unimorph piezoceramic actuator. The artificial wings are first made of a thin polyethylene sheet and then corrugated. As the wings are assembled through a pitching hinge, they can passively rotate about the hinge during the flapping motion due to the resultant aerodynamic force. The effects of the rotation, corrugation, and clapping of the wings are experimentally explored with respect to the vertical force produced by the flapping system. A smoke-wire flow visualization is also conducted to confirm whether the flapping-wing system can generate leading edge and trailing edge vortices, which are essential for generating lift and thrust in insect flight.
Individuals in Conflict: An Internal Family Systems Approach
Authors: Green Eric J.
Published: February 2008

Multiple models of therapy are available in the mental health profession to help couples cope with the psychological and interpersonal difficulties associated with marriage. Internal Family Systems (IFS) is one such theoretical paradigm that juxtaposes concepts of healing broken attachments and counseling premarital couples within a preventative context to bolster marital satisfaction. IFS therapy is an approach that treats couples, partners, and intimates by exposing vulnerable emotions between individuals and providing a dynamic method of communicating interpersonal wounds with the ultimate therapeutic goal of reparation. Marriage and family therapists are uniquely positioned to assist couples in the inherent struggles associated with matrimony by using IFS therapy. This article explores the application of IFS therapy to individuals by providing a case study to highlight its impact on repairing a conflictual marriage.
Counselors'-in-Training Perceptions of Gendered Behavior
Authors: Trepal Heather C. , Wester Kelly L. , Shuler Michelle
Published: February 2008

This study utilized Q methodology to examine counselors'-in-training (CIT) perceptions of gendered behavior. Findings supported that most CITs adhered to a traditional view of gender. To work effectively with couples and families, it is suggested that counselors need to address and explore potential biases and socialized stereotypes of gender.