bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interactions between Partner Switcher Orthologs BtrW and BtrV Regulate Type III Secretion in
Bordetella
Authors: Kozak Natalia A. , Mattoo Seema , Foreman-Wykert Amy K. , Whitelegge Julian P. , Miller Jeff F. 
Published: August 2005

ABSTRACT

We have recently described a multicomponent cascade that regulates type III secretion in
Bordetella
. This cascade includes a group of proteins, BtrU, BtrW, and BtrV, that contain an array of domains that define partner-switching complexes previously characterized in gram-positive bacteria. BtrU contains a PP2C-like serine phosphatase domain, BtrW contains a serine kinase/anti-sigma factor motif, and BtrV includes an anti-sigma factor antagonist domain. On the basis of genetic studies and sequence similarity with the RsbU-RsbW-RsbV and SpoIIE-SpoIIAB-SpoIIAA partner switchers of
Bacillus subtilis
, a series of interactions between
Bordetella
orthologs have been proposed. Bacterial two-hybrid analysis, tagged protein pull-downs, and in vitro phosphorylation assays were used to characterize interactions between BtrW and BtrV. In addition, BtrV mutants predicted to mimic a constitutively phosphorylated form of BtrV or to be nonphosphorylatable and BtrW mutants defective in serine kinase activity or the ability to bind BtrV were constructed and analyzed. Our results demonstrate that (i) BtrW and BtrV interact with each other, (ii) BtrW phosphorylates BtrV at serine S55, (iii) the conserved serine residue S55 of BtrV plays a key role in BtrV-BtrW interactions, and (iv) the ability of BtrW to phosphorylate BtrV and disrupt BtrV-BtrW binding is essential for the type III secretion process.
Deletion of the
Mycobacterium tuberculosis pknH
Gene Confers a Higher Bacillary Load during the Chronic Phase of Infection in BALB/c Mice
Authors: Papavinasasundaram K. G. , Chan Bosco , Chung Ji-Hae , Colston M. Joseph , Davis Elaine O. , Av-Gay Yossef 
Published: August 2005

ABSTRACT

The role of the serine/threonine kinase PknH in the physiology and virulence of
Mycobacterium tuberculosis
was assessed by the construction of a
pknH
deletion mutant. Deletion of the
pknH
gene did not affect sensitivity to the antimycobacterial drug ethambutol, although it was previously thought to be involved in regulating expression of
emb
genes encoding arabinosyl transferases, the targets of ethambutol. Nevertheless, transcription analyses revealed that genes associated with mycobacterial cell wall component synthesis, such as
emb
and
ini
operons, are downstream substrates of the PknH signaling cascade. In vitro survival studies revealed that a mutant with a deletion of the
pknH
gene displayed increased resistance to acidified nitrite stress, suggesting that nitric oxide is one of the potential environmental triggers for PknH activation. The effect of
pknH
deletion on mycobacterial virulence was investigated in BALB/c mice. In this model, the Δ
pknH
mutant was found to survive and replicate to a higher bacillary load in mouse organs than its parental strain and the
pknH
-complemented strain. In contrast, another closely related kinase mutant, the Δ
pknE
mutant, obtained from the same parental strain, was not affected in its virulence phenotype. Infection of THP-1 cells or in vitro growth studies in 7H9 medium did not reveal a significant in vitro growth advantage phenotype for the Δ
pknH
mutant. In conclusion, we propose that the serine/threonine kinase PknH plays a role in regulating bacillary load in mouse organs to facilitate adaptation to the host environment, possibly by enabling a regulated chronic infection by
M. tuberculosis
.
The
pnhA
Gene of
Pasteurella multocida
Encodes a Dinucleoside Oligophosphate Pyrophosphatase Member of the Nudix Hydrolase Superfamily
Authors: Urick Tonia , I-Chang Chien , Arena Ellen , Xu WenLian , Bessman Maurice J. , Ruffolo Carmel G. 
Published: August 2005

ABSTRACT

The
pnhA
gene of
Pasteurella multocida
encodes PnhA, which is a member of the Nudix hydrolase subfamily of dinucleoside oligophosphate pyrophosphatases. PnhA hydrolyzes diadenosine tetra-, penta
-
, and hexaphosphates with a preference for diadenosine pentaphosphate, from which it forms ATP and ADP. PnhA requires a divalent metal cation, Mg
2+
or Mn
2+
, and prefers an alkaline pH of 8 for optimal activity. A
P. multocida
strain that lacked a functional
pnhA
gene, ACP13, was constructed to further characterize the function of PnhA. The cellular size of ACP13 was found to be 60% less than that of wild-type
P. multocida
, but the growth rate of ACP13 and its sensitivity to heat shock conditions were similar to those of the wild type, and the wild-type cell size was restored in the presence of a functional
pnhA
gene. Wild-type and ACP13 strains were tested for virulence by using the chicken embryo lethality model, and ACP13 was found to be up to 1,000-fold less virulent than the wild-type strain. This is the first study to use an animal model in assessing the virulence of a bacterial strain that lacked a dinucleoside oligophosphate pyrophosphatase and suggests that the pyrophosphatase PnhA, catalyzing the hydrolysis of diadenosine pentaphosphates, may also play a role in facilitating
P. multocida
pathogenicity in the host.
Ophite Gnosticism, Sethianism and the Nag Hammadi Library
Authors: Rasimus Tuomas 
Published: August 2005

AbstractThis article discusses the definition of Ophite Gnosticism, its relationship to Sethian Gnosticism, and argues that Eugnostos, Soph. Jes. Chr., Orig. World, Hyp. Arch. and Ap. John not only have important links with each other but also draw essentially on the mythology the heresiologists called that of the Ophites. Before the Nag Hammadi findings, Ophite Gnosticism was often seen as an important and early form of Gnosticism, rooted in Jewish soil, and only secondarily Christianized. Today, not only are similar claims made of Sethian Gnosticism, but also some of the above-mentioned texts are classified as Sethian. In many recent studies, the Ophite mythology is connected with Sethian Gnosticism, even though the exact relationship between these two forms of Gnosticism has remained unclear. It is argued here that the Sethian Gnostic authors drew on earlier forms of Gnosticism, especially on the Ophite mythology, in composing some of the central Sethian texts.
Rhabdomyosarcoma: New Windows of Opportunity
Authors: Breitfeld Philip P. , Meyer William H. 
Published: August 2005

AbstractLearning ObjectivesAfter completing this course, the reader will be able to: Interpret the histologic findings of rhabdomyosarcoma and differentiate rhabdomyosarcoma from other small round cell neoplasms.Define the extent of disease using the Intergroup Rhabdomyosarcoma Study stage and group systems and apply these systems to predict prognosis.Discuss the multidisciplinary nature of therapy for rhabdomyosarcoma.Evaluate the most appropriate risk-based therapy alternatives for rhabdomyosarcoma.Access and take the CME test online and receive 1 hour of AMA PRA category 1 credit at CME.TheOncologist.comRhabdomyosarcoma is a highly malignant, small blue cell tumor characterized by muscle differentiation. With modern treatment, more than 70% of children and adolescents with this disease are cured. Adequate biopsy to obtain sufficient tissue for accurate diagnosis and molecular characterization is critical. Patients must be assessed for tumor extent; the Intergroup Rhabdomyosarcoma Study (IRS) clinical group and Staging system is universally applied in North America. Multidisciplinary therapy is necessary to maximize cure rates. Local control relies on complete surgical excision when possible; those whose tumors are not completely excised and those with alveolar histology tumors require local irradiation to maximize local control. In North America, vincristine (Oncovin®; Eli Lilly and Company, Indianapolis, http://www.lilly.com), dactinomycin (Cosmegen®; Merck & Co., Inc., Whitehouse Station, NJ, http://www.merck.com), and cyclophosphamide are the standard chemotherapy agents. The IRS has used therapeutic window studies to confirm the predictive nature of preclinical xenograft models and to identify several new single agents and combinations of agents with activity in high-risk patient groups. Despite these efforts, the outcome for these high-risk patients remains poor. The next generation of Children's Oncology Group studies will evaluate the efficacy of topoisomerase-I inhibitors and dose-compression therapy approaches. New advances in molecular characterization of tumors, including gene-expression analysis, may identify new therapeutic targets that can be exploited by expanded preclinical drug discovery efforts, and hold the promise of revolutionizing risk-based therapies.
Placental improvement and reduced distal limb defects by maternal interferon‐γ injection in methylnitrosourea‐exposed mice
Authors: Laudermilch Chelsea Lee , Holladay Steven David , Sponenberg Dan Phillip , Saunders Geoffrey Kirk , Ward Daniel Lee , Prater Mary Renee 
Published: August 2005

AbstractBackgroundMethylnitrosourea (MNU), an alkylating agent derived from creatinine metabolism, is cytotoxic, genotoxic, and mutagenic. Midgestational exposure to MNU leads to distal limb defects in mice. Previous studies have shown that nonspecific maternal immune stimulation protects against MNU‐induced teratogenesis. A role for immune‐mediated placental improvement in this effect remains uncertain.METHODSThe immune system of timed‐pregnant C57BL/6N and CD‐1 mice was stimulated by GD 7 intraperitoneal (IP) injection with the cytokine interferon‐γ (IFN‐γ). A teratogenic dose of MNU was then administered by IP injection on the morning of GD 9 to disrupt distal limb formation. Fetal limb length, body length, digital deformities, and placental integrity were evaluated on GD 14.RESULTSThe incidence of syndactyly, polydactyly, and interdigital webbing in MNU‐exposed mice was decreased by maternal IFN‐γ treatment. In C57BL/6N mice, these defects were reduced by 47, 100, and 63%, respectively, as compared to previous reports on CD‐1 mice, by 39, 71, and 20%, respectively. Administration of IFN‐γ significantly diminished MNU‐induced endothelial and trophoblast placental damage in both strains of mice.CONCLUSIONSThese findings support a possible link between maternal immunity, placental integrity, and fetal distal limb development. Further, these results suggest that IFN‐γ might act through placental improvement to indirectly protect against MNU‐induced fetal limb malformations. Birth Defects Research (Part A), 2005. © 2005 Wiley‐Liss, Inc.
Fluorescence anisotropy studies of molecularly imprinted polymers
Authors: Chen Yin‐Chu , Wang Zheming , Yan Mingdi , Prahl Scott A. 
Published: August 2005

AbstractA molecularly imprinted polymer (MIP) is a biomimetic material that can be used as a biochemical sensing element. We studied the steady‐state and time‐resolved fluorescence and fluorescence anisotropy of anthracene‐imprinted polyurethane. We compared MIPs with imprinted analytes present, MIPs with the imprinted analytes extracted, MIPs with rebound analytes, non‐imprinted control polymers (non‐MIPs) and non‐MIPs bound with analytes to understand MIP's binding behaviour. MIPs and non‐MIPs had similar steady‐state fluorescence anisotropy in the range 0.11–0.24. Anthracene rebound in MIPs and non‐MIPs had a fluorescence lifetime of τ = 0.64 ns and a rotational correlation time of ϕF = 1.2–1.5 ns, both of which were shorter than that of MIPs with imprinted analytes present (τ = 2.03 ns and ϕF = 2.7 ns). The steady‐state anisotropy of polymer solutions increased exponentially with polymerization time and might be used to characterize the polymerization extent in situ. Copyright © 2005 John Wiley & Sons, Ltd.
Determination of norfloxacin using a terbium‐sensitized electrogenerated chemiluminescence method
Authors: Chen Shi‐Lv , Liu Yu , Zhao Hui‐Chun , Jin Lin‐Pei , Zhang Zhong‐Lun , Zheng Yan‐Zhen 
Published: August 2005

AbstractA simple electrogenerated chemiluminescence (ECL) analysis method for the determination of norfloxacin (NFLX) is reported. It is based on ECL produced by Na2SO3, which is sensitized by the Tb–NFLX complex. The relative ECL intensity of the Tb3+–NFLX–Na2SO3 system is proportional to the amount of NFLX. The optimized experimental conditions were investigated. The linear range and detection limit for NFLX were 1.0 × 10−10–8.0 × 10−7 mol/L and 2.8 × 10−11 mol/L, respectively. This method was successfully applied to the determination of NFLX in a capsule. NFLX in urine can be directly detected without pretreatment or separation. Copyright © 2005 John Wiley & Sons, Ltd.
Production of phytoene by herbicide‐treated microalgae Dunaliella bardawil in two‐phase systems
Authors: León Rosa , Vila Marta , Hernánz Dolores , Vílchez Carlos 
Published: August 2005

AbstractIn the present study we have optimized the concentration of the bleaching herbicide norflurazon to obtain Dunaliella bardawil cells able to accumulate phytoene without losing viability. The highest concentration of phytoene 10.4 g/gChl was obtained for a concentration of norflurazon of 10 µg/mL. Norflurazon‐treated Dunaliella bardawil cells are able to accumulate high concentrations of phytoene if the carotenogenic pathway is stimulated, but the lack of colored carotenoids make these cells particularly sensitive to high light intensities and to UVB radiation, so other stimuli, such as nitrogen starvation, have to be used to force the accumulation of phytoene. Detailed time‐course evolution of the carotenoids lutein, violaxanthin, zeaxanthin, phytene and β‐carotene and the photosynthetic pigment chlorophyll was followed upon transfer of Dunaliella bardawil cells to nitrogen starvation in presence and absence of norflurazon. The combined use of the carotenogenic pathway inhibitor norflurazon and biphasic aqueous/organic systems to force the excretion of phytoene into the culture medium has been investigated. Cells cultured in the biphasic system were viable and able to produce phytoene during 3 days. Futhermore the productivity increased from 0.14 g/gChl · h in the aqueous culture to 0.18 g/gChl · h in the biphasic system. About 15% of the total phytoene produced by Dunaliella bardawil was excreted and immediately partionated into the organic phase. The concentration of phytoene in the decane phase was 2.05 g/gChl after 72 h, this means that about 47 g of phytoene per litre of culture were in the organic phase. © 2005 Wiley Periodicals, Inc.
C5 complement inhibition attenuates shock and acute lung injury in an experimental model of ruptured abdominal aortic aneurysm
Authors: Harkin D W , Marron C D , Rother R P , Romaschin A , Rubin B B , Lindsay T F 
Published: August 2005

AbstractBackgroundRuptured abdominal aortic aneurysm (RAAA) is associated with a systemic inflammatory response syndrome and multiple organ dysfunction. The potential role of a novel C5 complement inhibitor in attenuation of pathological complement activation and tissue injury was explored in a model of RAAA.MethodsAnaesthetized rats were randomized to sham (control) or shock and clamp (SC) groups. Animals in the SC group underwent 1 h of haemorrhagic shock (mean arterial pressure 50 mmHg or less), 45 min of supramesenteric aortic clamping and 2 h of reperfusion. They were randomized to receive an intravenous bolus of a functionally blocking anti-C5 monoclonal antibody (C5 inhibitor), at a dose of 20 mg/kg, or saline. Lung injury was assessed by permeability to 125I-labelled albumin, tissue myeloperoxidase (MPO) activity, and semiquantitative reverse transcriptase–polymerase chain reaction (RT–PCR) for mRNAs encoding tumour necrosis factor (TNF) α and interleukin (IL) 6.ResultsThe lung permeability index was significantly increased in the SC compared with the sham group (P = 0·032); this was prevented by the C5 inhibitor (P = 0·015). Lung MPO activity was significantly increased in the SC compared with the sham group (P &lt; 0·001), and this increase was attenuated by treatment with the C5 inhibitor (P &lt; 0·001). Semiquantitative RT–PCR in SC group demonstrated downregulation of TNF-α mRNA (P = 0·050) and upregulation of IL-6 mRNA (P &lt; 0·001), which were both prevented by the C5 inhibitor (P = 0·014 and P &lt; 0·001 respectively).ConclusionThese results indicated that C5 complement inhibition can reduce shock and acute lung injury in an experimental model of RAAA.
Policy instruments for sustainability‐oriented organizational learning
Authors: Müller Martin , Siebenhüner Bernd 
Published: August 2005

AbstractThe concept of sustainable development implies the need for organizational learning in business corporations to find innovative solutions. In this context, the paper analyzes the requirements and options for environmental policy to induce sustainability‐related learning processes in corporations. It discusses the impacts of different policy instruments on these processes.Initially, the particular challenges of organizational learning for sustainability are being sketched out. Drawing on organizational learning studies, a subsequent section of the paper addresses fundamental elements and drivers for organizational learning processes on different levels in business corporations. The particular nodes where public policy can influence corporate learning processes are the central focus of these considerations. On this basis, we examine existing policy instruments frequently used in environmental policy with regard to their potential to foster learning processes towards sustainability. Copyright © 2005 John Wiley & Sons, Ltd and ERP Environment.
Amplification and overexpression of prosaposin in prostate cancer
Authors: Koochekpour Shahriar , Zhuang Yu‐Jun , Beroukhim Rameen , Hsieh Chia‐Ling , Hofer Matthias D. , Zhau Haiyen E. , Hiraiwa Masao , Pattan Daniel Y. , Ware Joy L. , Luftig Ronald B. , Sandhoff Konrad , Sawyers Charles L. , Pienta Kenneth J. , Rubin Mark A. , Vessella Robert L. , Sellers William R. , Sartor Oliver 
Published: August 2005

AbstractWe identified prosaposin (PSAP) as a secreted protein expressed in androgen‐independent (AI) prostate cancer cells by cloning/sequencing, after probing a PC‐3 cDNA library expressed in the λTriplEx phagemid expression vector with a polyclonal rabbit antibody generated against pooled human seminal plasma. PSAP is a neurotrophic molecule; its deficiency or inactivation has proved to be lethal in man and mice, and in mice, it leads to abnormal development and atrophy of the prostate gland, despite normal testosterone levels. We used Southern hybridization, quantitative real‐time polymerase chain reaction, and/or single nucleotide polymorphism (SNP) array analysis, and we now report the genomic amplification of PSAP in the metastatic AI prostate cancer cell lines, PC‐3, DU‐145, MDA‐PCa 2b, M‐12, and NCI‐H660. In addition, by using SNP arrays and a set of 25 punch biopsy samples of human prostate cancer xenografts (LAPC3, LuCaP 23.1, 35, 49, 58, 73, 77, 81, 86.2, 92.1, 93, 96, 105, and 115), lymph nodes, and visceral‐organ metastases, we detected amplification of the PSAP locus (10q22.1) in LuCaP 58 and 96 xenografts and two lymph node metastases. In addition, AI metastatic prostate cancer cell lines C4‐2B and IA8‐ARCaP over‐expressed PSAP mRNA without evidence of genomic amplification. Taken together with prior data that demonstrated the growth‐, migration‐, and invasion‐promoting activities, the activation of multiple signal transduction pathways, and the antiapoptotic effect of PSAP (or one of its active domains, saposin C) in prostate cancer cells, our current observation of PSAP amplification or overexpression in prostate cancer suggests, for the first time, a role for this molecule in the process of carcinogenesis or cancer progression in the prostate. © 2005 Wiley‐Liss, Inc.
Direction‐dependent visual cortex activation during horizontal optokinetic stimulation (fMRI study)
Authors: Bense Sandra , Janusch Barbara , Schlindwein Peter , Bauermann Thomas , Vucurevic Goran , Brandt Thomas , Stoeter Peter , Dieterich Marianne 
Published: August 2005

AbstractLooking at a moving pattern induces optokinetic nystagmus (OKN) and activates an assembly of cortical areas in the visual cortex, including lateral occipitotemporal (motion‐sensitive area MT/V5) and adjacent occipitoparietal areas as well as ocular motor areas such as the prefrontal cortex, frontal, supplementary, and parietal eye fields. The aim of this functional MRI (fMRI) study was to investigate (1) whether stimulus direction‐dependent effects can be found, especially in the cortical eye fields, and (2) whether there is a hemispheric dominance of ocular motor areas. In a group of 15 healthy subjects, OKN in rightward and leftward directions was visually elicited and statistically compared with the control condition (stationary target) and with each other. Direction‐dependent differences were not found in the cortical eye fields, but an asymmetry of activation occurred in paramedian visual cortex areas, and there were stronger activations in the hemisphere contralateral to the slow OKN phase (pursuit). This can be explained by a shift of the mean eye position of gaze (beating field) in the direction of the fast nystagmus phases of approximately 2.6 degrees, causing asymmetrical visual cortex stimulation. The absence of a significant difference in the activation pattern of the cortical eye fields supports the view that the processing of eye movements in both horizontal directions is mediated in the same cortical ocular motor areas. Furthermore, no hemispheric dominance for OKN processing was found in right‐handed volunteers. Hum Brain Mapp, 2005. © 2005 Wiley‐Liss, Inc.
Karakorum–Hindukush–western Himalaya: assessing high‐altitude water resources
Authors: Winiger M. , Gumpert M. , Yamout H. 
Published: August 2005

AbstractThe high mountains of Central and South Asia provide irrigation water for their adjacent lowlands. The Indus Irrigation Scheme depends on approximately 50% of its runoff originating from snowmelt and glacier melt from the eastern Hindukush, Karakorum and western Himalaya. The Atlas of Pakistan indicates that these mountains gain a total annual rainfall of between 200 and 500 mm, amounts that are generally derived from valley‐based stations and not representative for elevated zones. High‐altitude snowfall seems to be neglected and is obviously still rather unknown. Estimates derived from accumulation pits runoff above 4000 m range from 1000 mm to more than 3000 mm, depending on the site and time of investigation, as well as on the method applied.To assess the vertical spatio‐temporal distribution of total annual precipitation, a combined approach is presented. This approach links in situ measurements of snow depth and water equivalent (10‐year time series derived from automatic weather stations at elevations between 1500 and 4700 m a.s.l.), the spatial distribution and period of snow coverage (remotely sensed data and digital elevation models), and the runoff characteristics of streams originating from snow or snow/ice‐covered watersheds (modified snowmelt runoff model, including intermediate snowfall and glacier runoff).Based on conservative assumptions, the vertically changing seasonal ratio between liquid and solid precipitation is calculated. Using a combined snow cover and ablation model, total annual amounts of precipitation are derived for different altitudinal zones. Amounts of modelled and measured runoff complement the investigation. Horizontal gradients along the Indus–Gilgit–Hunza transect indicate the varying dominance of seasonal precipitation regimes (monsoonal, Mediterranean and continental disturbances) south of Nanga Parbat, between Nanga Parbat and Batura Wall (=West Karakorum rainfall regime: 1500–1800 mm year−1 at 5000 m) and areas north of Batura (=Central Asian rainfall regime: ∼600 mm year−1 at 5000 m). Copyright © 2005 John Wiley & Sons, Ltd.