bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacterial Endosymbiont of the Slender Pigeon Louse,Columbicola columbae, Allied to Endosymbionts of Grain Weevils and Tsetse Flies
Authors: Fukatsu Takema , Koga Ryuichi , Smith Wendy A. , Tanaka Kohjiiro , Nikoh Naruo , Sasaki-Fukatsu Kayoko , Yoshizawa Kazunori , Dale Colin , Clayton Dale H. 
Published: September 2007

ABSTRACTThe current study focuses on a symbiotic bacterium found in the slender pigeon louse,Columbicola columbae(Insecta: Phthiraptera). Molecular phylogenetic analyses indicated that the symbiont belongs to the gamma subdivision of the classProteobacteriaand is allied toSodalis glossinidius, the secondary symbiont of tsetse flies (Glossinaspp.) and also to the primary symbiont of grain weevils (Sitophilusspp.). Relative-rate tests revealed that the symbiont ofC. columbaeexhibits accelerated molecular evolution in comparison with the tsetse fly symbiont and the weevil symbiont. Whole-mount in situ hybridization was used to localize the symbiont and determine infection dynamics during host development. In first- and second-instar nymphs, the symbionts were localized in the cytoplasm of oval bacteriocytes that formed small aggregates on both sides of the body cavity. In third-instar nymphs, the bacteriocytes migrated to the central body and were finally located in the anterior region of the lateral oviducts, forming conspicuous tissue formations called ovarial ampullae. In adult females, the symbionts were transmitted from the ovarial ampullae to developing oocytes in the ovarioles. In adult males, the bacteriocytes often disappeared without migration. A diagnostic PCR survey of insects collected from Japan, the United States, Australia, and Argentina detected 96.5% (109/113) infection, with a few uninfected male insects. This study provides the first microbial characterization of a bacteriocyte-associated symbiont from a chewing louse. Possible biological roles of the symbiont are discussed in relation to the host nutritional physiology associated with the feather-feeding lifestyle.
Artemisinin Induces Calcium-Dependent Protein Secretion in the Protozoan ParasiteToxoplasma gondii
Authors: Nagamune Kisaburo , Beatty Wandy L. , Sibley L. David 
Published: September 2007

ABSTRACTIntracellular calcium controls several crucial cellular events in apicomplexan parasites, including protein secretion, motility, and invasion into and egress from host cells. The plant compound thapsigargin inhibits the sarcoplasmic-endoplasmic reticulum calcium ATPase (SERCA), resulting in elevated calcium and induction of protein secretion inToxoplasma gondii. Artemisinins are natural products that show potent and selective activity against parasites, making them useful for the treatment of malaria. While the mechanism of action is uncertain, previous studies have suggested that artemisinin may inhibit SERCA, thus disrupting calcium homeostasis. We cloned the single-copy gene encoding SERCA inT. gondii(TgSERCA) and demonstrate that the protein localizes to the endoplasmic reticulum in the parasite. In extracellular parasites, TgSERCA partially relocalized to the apical pole, a highly active site for regulated secretion of micronemes. TgSERCA complemented a calcium ATPase-defective yeast mutant, and this activity was inhibited by either thapsigargin or artemisinin. Treatment ofT. gondiiwith artemisinin triggered calcium-dependent secretion of microneme proteins, similar to the SERCA inhibitor thapsigargin. Artemisinin treatment also altered intracellular calcium in parasites by increasing the periodicity of calcium oscillations and inducing recurrent, strong calcium spikes, as imaged using Fluo-4 labeling. Collectively, these results demonstrate that artemisinin perturbs calcium homeostasis inT. gondii, supporting the idea that Ca2+-ATPases are potential drug targets in parasites.
Safety and Protective Efficacy of Intramuscular Vaccination with a LivearoADerivative ofPasteurella multocidaB:2 against Experimental Hemorrhagic Septicemia in Calves
Authors: Dagleish Mark P. , Hodgson J. Christopher , Ataei Saeed , Finucane Anna , Finlayson Jeanie , Sales Jill , Parton Roger , Coote John G. 
Published: September 2007

ABSTRACTThree groups of five calves, namely, V1, V2, and V3, were immunized intramuscularly at 4 and 8 weeks of age with ca. 109, 108, and 107CFU, respectively, of a derivative ofPasteurella multocidaB:2 wild-type strain 85020 containing a deletion in thearoAgene (strain JRMT12). The first and second vaccinations resulted in significantly (P< 0.01) higher rectal temperature responses in groups V1 and V2 than in group V3. Serum immunoglobulin M (IgM) and IgG titers did not increase in any group until after the second vaccination and were then significantly higher in groups V1 and V2 than in group V3 (P= 0.001 for both IgM and IgG). All vaccinated groups and three unvaccinated challenge control calves (group CC) were injected subcutaneously at 10 weeks of age with ca. 107CFU of strain 85020. Vaccinated calves survived the challenge, but two CC animals developed clinical disease and were killed for humane reasons. After challenge, mean serum amyloid A concentrations were significantly higher (P< 0.001) in the CC group than in the vaccinated groups. Postmortem examination revealed that calves in the CC group showed the most extensive range of bacteriologically positive tissues and gross and histopathological lesions. Overall, a clear dose-dependent response was present, with those receiving a higher vaccine dose being less affected clinically, bacteriologically, and pathologically by the wild-type challenge. The V2 treatment appeared to give the best combination of high immune response, protection, and safety.
Chlamydophila pneumoniae
PknD Exhibits Dual Amino Acid Specificity and Phosphorylates Cpn0712, a Putative Type III Secretion YscD Homolog
Authors: Johnson Dustin L. , Mahony James B. 
Published: September 2007

ABSTRACT

Chlamydophila pneumoniae
is an obligate intracellular bacterium that causes bronchitis, pharyngitis, and pneumonia and may be involved in atherogenesis and Alzheimer's disease. Genome sequencing has identified three eukaryote-type serine/threonine protein kinases, Pkn1, Pkn5, and PknD, that may be important signaling molecules in
Chlamydia
. Full-length PknD was cloned and expressed as a histidine-tagged protein in
Escherichia coli
. Differential centrifugation followed by sodium carbonate treatment of
E. coli
membranes demonstrated that His-PknD is an integral membrane protein. Fusions of overlapping PknD fragments to alkaline phosphatase revealed that PknD contains a single transmembrane domain and that the kinase domain is in the cytoplasm. To facilitate solubility, the kinase domain was cloned and expressed as a glutathione
S
-transferase (GST) fusion protein in
E. coli
. Purified GST-PknD kinase domain autophosphorylated, and catalytic mutants (K33G, D156G, and K33G-D156G mutants) and activation loop mutants (T185A and T193A) were inactive. PknD phosphorylated recombinant Cpn0712, a type III secretion YscD homolog that has two forkhead-associated domains. Thin-layer chromatography revealed that the PknD kinase domain autophosphorylated on threonine and tyrosine and phosphorylated the FHA-2 domain of Cpn0712 on serine and tyrosine. To our knowledge, this is the first demonstration of a bacterial protein kinase with amino acid specificity for both serine/threonine and tyrosine residues and this is the first study to show phosphorylation of a predicted type III secretion structural protein.
Pseudomonas aeruginosaAlgR Represses the Rhl Quorum-Sensing System in a Biofilm-Specific Manner
Authors: Morici Lisa A. , Carterson Alexander J. , Wagner Victoria E. , Frisk Anders , Schurr Jill R. , zu Bentrup Kerstin Höner , Hassett Daniel J. , Iglewski Barbara H. , Sauer Karin , Schurr Michael J. 
Published: September 2007

ABSTRACTAlgR controls numerous virulence factors inPseudomonas aeruginosa, including alginate, hydrogen cyanide production, and type IV pilus-mediated twitching motility. In this study, the role of AlgR in biofilms was examined in continuous-flow and static biofilm assays. Strain PSL317 (ΔalgR) produced one-third the biofilm biomass of wild-type strain PAO1. Complementation withalgR, but notfimTU-pilVWXY1Y2E, restored PSL317 to the wild-type biofilm phenotype. Comparisons of the transcriptional profiles of biofilm-grown PAO1 and PSL317 revealed that a number of quorum-sensing genes were upregulated in thealgRdeletion strain. Measurement ofrhlA::lacZandrhlI::lacZpromoter fusions confirmed the transcriptional profiling data when PSL317 was grown as a biofilm, but not planktonically. Increased amounts of rhamnolipids andN-butyryl homoserine lactone were detected in the biofilm effluent but not the planktonic supernatants of thealgRmutant. Additionally, AlgR specifically bound to therhlAandrhlIpromoters in mobility shift assays. Moreover, PAO1 containing a chromosomal mutated AlgR binding site in itsrhlIpromoter formed biofilms and produced increased amounts of rhamnolipids similarly to thealgRdeletion strain. These observations indicate that AlgR specifically represses the Rhl quorum-sensing system during biofilm growth and that such repression is necessary for normal biofilm development. These data also suggest that AlgR may control transcription in a contact-dependent or biofilm-specific manner.
Do workers with self-reported symptoms have an elevated risk of developing upper extremity musculoskeletal disorders three years later?
Authors: Descatha A , Chastang J F , Cyr D , Leclerc A , Roquelaure Y , Evanoff B 
Published: September 2007

Objectives:Few prospective studies have evaluated outcomes of workers with self-reported symptoms of upper extremity musculoskeletal disorders (UEMSD). The objective was to study the three-year outcomes of workers with self-reported symptoms, with or without a positive physical examination.Methods:In 1993–4, 598 subjects highly exposed to repetitive work filled out a Nordic-style questionnaire. They underwent a standardised physical examination at that time and again in 1996–7 by the same occupational physician. The three-year outcomes (based on physical examination) of workers with a self-administered questionnaire positive at baseline for UEMSD, with or without a positive physical examination, were studied.Results:The three-year incidence rate was 44.1%; one third of these incident cases had self-reported symptoms in 1993–4. Workers with a positive questionnaire had a significantly higher risk of UEMSD at physical examination three years later (80.1% UEMSD cases with positive questionnaires n = 354, vs 44.2% cases without positive questionnaires n = 69, p<0.001). Moreover, workers with positive questionnaires but without UEMSD diagnosed in 1993–4 (n = 177) also had a significantly higher risk of UEMSD at physical examination three years later (60.5% cases with positive questionnaires n = 26, vs 38.8% cases without positive questionnaires n = 52, p = 0.01). Results were similar when gender and age were taken into account.Conclusion:Workers highly exposed to repetitive movements have a high risk of developing UEMSD and should be followed closely in surveillance programmes. Workers with self-reported symptoms without UEMSD diagnosed in physical examination represented only one third of new cases three years later. However, their risk of developing UEMSD was significantly increased, compared with those without symptoms.
Design and Implementation of a Low Power Ternary Full Adder
Authors: Srivastava A. , Venkatapathy K. 
Published: September 2007

In this work, the design and implementation of a low power ternary full adder are presented in CMOS technology. In a ternary full adder design, the basic building blocks, the positive ternary inverter (PTI) and negative ternary inverter (NTI) are developed using a CMOS inverter and pass transistors. In designs of PTI and NTI, W/L ratios of transistors have been varied for their optimum performance. The ternary full adder and its building blocks have been simulated with SPICE 2G.6 using the MOSIS model parameters. The rise and fall times of PTI show an improvement by a factor of 14 and 4, respectively, and that of the NTI by a factor of nearly 4 and 17, respectively over that of earlier designs implemented in depletion‐enhancement CMOS (DECMOS) technology. The noise margins improve by a factor of nearly 2 in PTI and NTI, respectively.The ternary full adder has been fabricated in MOSIS two micron n‐well CMOS technology. The full adder and its building blocks, NTI and PTI have been tested experimentally for static and dynamic performance, compared with the SPICE simulated behavior, and close agreement is observed.The ternary‐valued logic circuits designed in the present work which do not use depletion mode MOSFETS perform better than that implemented earlier in DECMOS technology. The present design is fully compatible with the current CMOS technology, uses fewer components and dissipates power in the microwatt range.
Automated Synthesis of Skew‐Based Clock Distribution Networks
Authors: Neves José Luis , Friedman Eby G. 
Published: September 2007

In this paper a top‐down methodology is presented for synthesizing clock distribution
networks based on application‐dependent localized clock skew. The methodology is
divided into four phases: 1) determination of an optimal clock skew schedule for
improving circuit performance and reliability; 2) design of the topology of the clock tree
based on the circuit hierarchy and minimum clock path delays; 3) design of circuit
structures to implement the delay values associated with the branches of the clock tree;
and 4) design of the geometric layout of the clock distribution network. Algorithms to
determine an optimal clock skew schedule, the optimal clock delay to each register, the
network topology, and the buffer circuit dimensions are presented.The clock distribution network is implemented at the circuit level in CMOS
technology and a design strategy based on this technology is presented to implement the
individual branch delays. The minimum number of inverters required to implement the
branch delays is determined, while preserving the polarity of the clock signal. The clock
lines are transformed from distributed resistive‐capacitive interconnect lines into purely
capacitive interconnect lines by partitioning the RC interconnect lines with inverting
repeaters. The inverters are specified by the geometric size of the transistors, the slope of
the ramp shaped input/output waveform, and the output load capacitance. The branch
delay model integrates an inverter delay model with an interconnect delay model.
Maximum errors of less than 2.5% for the delay of the clock paths and 4% for the clock
skew between any two registers belonging to the same global data path are obtained as
compared with SPICE Level‐3.
Architectural Power Estimation Based on Behavior Level Profiling
Authors: Katkoori Srinivas , Vemuri Ranga 
Published: September 2007

High level synthesis is the process of generating register transfer (RT) level designs from
behavioral specifications. High level synthesis systems have traditionally taken into
account such constraints as area, clock period and throughput time. Many high level
synthesis systems [1] permit generation of many alternative RT level designs meeting
these constraints in a relatively short time. If it is possible to accurately estimate the
power consumption of RT level designs, then a low power design from among these
alternatives can be selected.In this paper, we present an accurate power estimation technique for register transfer
level designs generated by high level synthesis systems. The technique has four main
aspects: (1) Each RT level component used in high level synthesis is characterized for
average switched capacitance per input vector. This data is stored in the RT level
component library. (2) Using user‐specified stimuli, the given behavioral description is
simulated and event activities of various operators and carriers are measured. Then, the
behavioral specification is submitted to the synthesis system and a number of alternative
RTL designs meeting speed, space and throughput rate constraints are generated. (3)
Event activity of each component in an RT level design is estimated using the event
activities measured at the time of behavior level profiling and the structure of the RTL
design itself. (4) The event activities so obtained are then used to modulate the average
switched capacitances of the respective RT level components to obtain an estimate the
total switched capacitance of each component.Detailed power estimation procedures for the three different parts of RTL designs,
namely, data path, controller and interconnect are presented. Experimental results
obtained from a variety of designs show that the power estimates are within 3%–10%
of the actual power measured by simulating the transistor level designs extracted from
mask layouts.
Synthesis and biological activity of stable branched neurotensin peptides for tumor targeting
Authors: Falciani Chiara , Fabbrini Monica , Pini Alessandro , Lozzi Luisa , Lelli Barbara , Pileri Silvia , Brunetti Jlenia , Bindi Stefano , Scali Silvia , Bracci Luisa 
Published: September 2007

AbstractReceptors for endogenous regulatory peptides, like the neuropeptide neurotensin, are overexpressed in several human cancers and can be targets for peptide-mediated tumor-selective therapy. Peptides, however, have the main drawback of an extremely short half-life in vivo. We showed that neurotensin and other endogenous peptides, when synthesized as dendrimers, retain biological activity and become resistant to proteolysis. Here, we synthesized the neurotensin functional fragment NT(8-13) in a tetrabranched form linked to different units for tumor therapy or diagnosis. Fluorescent molecules were used to monitor receptor binding and internalization in HT29 human adenocarcinoma cells and receptor binding in HT29 tumor xenografts in nude mice. Linking of chemotherapic molecules like chlorin e6 and methotrexate to dendrimers resulted in a dramatic increase in drug selectivity, uptake of which by target cells became dependent on peptide receptor binding. When nude mice carrying human tumor xenografts were treated with branched NT(8-13)-methotrexate, a 60% reduction in tumor growth was observed with respect to mice treated with the free drug. [Mol Cancer Ther 2007;6(9):2441–8]
Sensory and movement-led approach to design for Elderly Severely Mentally Ill units
Authors: Habell M. 
Published: September 2007

The evolution of a design embodying the alliance of movement to sensory stimulus for confused and Alzheimer sufferers. The paper is an account of the design concept of an Elderly Severely Mentally I11 (ESMI) unit under the Government Private Finance Initiative (PFI) rules. Previous papers by the author recorded the development of elderly care nursing units that sought to use the planning of circulation as a means to provide stimulation for patients. The results demonstrated a therapeutic value for this approach. In the latest version for ESMI, the concept has been taken further with the creation of a "Memory Trail" that provides a choice of routes with organised points of interest containing stimulus for the senses in order to trigger memory. This is seen as beneficial not only for patient but also provides a positive role for relatives in escorting and planning the "journey". The paper records how the design amended the original brief by the participation of user groups re-evaluating the requirements in discussion and visits to earlier versions of this approach.
Is childhood allergy more common amongst an island population?
Authors: Jeffs D. , Grainger R. , Powell P. 
Published: September 2007

A rise in the prevalence of childhood asthma has been reported in both the UK and in several overseas countries during recent years. Wide geographical variations have also been demonstrated in the dis tribution of hay fever, atopic eczema and other allergic symptoms. It is the impression of many parents and some clinicians that allergic symptoms may be even higher amongst children in an island envi ronment compared with a similar population on the mainland. To test this hypothesis, Guernsey and Jersey in the Channel Islands, and the Isle of Man in the Irish Sea participated as an inde pendent arm in the International Study of Asthma and Allergy in Childhood (ISAAC). This entailed self-completion of a 38-part pre- tested and validated questionnaire in a classroom setting under stan dardised conditions. A total of 3,772 secondary students in school years eight and nine living in the three islands were compared with 27,507 students of similar age in 93 British secondary schools enrolled in the larger UK study. There are a number of demonstrable differences in climate, home environment and lifestyle factors between the islands and mainland UK Although results were generally above the UK mean, they were comparable with the reference region of South West England and invariably below the UK maximum. For instance, the prevalence of 'ever wheezed?', 'wheezed in last twelve months?', 'wheezed with exercise?' and 'diagnosis of asthma' were a mean of 50.5%, 34.5%, 31% and 19.7% in the islands compared with a UK prevalence of 48.8%, 33.3%, 28.5% and 20.7%, whilst the prevalence of 'runny nose ever?' and `runny nose in last twelve months?' was a mean of 46.6% and 36.7% in the islands, compared with 47.1% and 37.9% in the UK mean. These differences were not statistically significant. This information will be reassuring to parents of island children, and also demonstrates that services for the management of asthma and other allergic conditions should not be a higher public health pri ority in these locations than on the mainland of Britain.
Risk factors for infant mortality in a rural community in Nigeria
Authors: Lawoyin T.O. 
Published: September 2007

In this prospective community based study, information on births and deaths was collected for five consecutive years (1993- 1997) by trained village health workers (VHW) and traditional birth attendants (TBA). The main objective was to identify fac tors which are associated with infant deaths in a typical rural community in southwestern Nigeria with a current mid-year population of 3,308. Infant mortality rate was found to be 68.2 per 1,000 live births and is lower than the national rate but high er than the regional rate. Neonatal deaths, with a rate of 37.6 per 1,000 live births, accounted for 55.1% of all infant deaths while postneonatal deaths accounted for 44.9% of the deaths. Twelve (44.4%) of all neonatal deaths (27) occurred within 24 h of delivery while 20 (74.1%) of all neonatal deaths occurred in the first week of life and were perinatal deaths. These high perinatal rates indicate that more efficient obstetric and public health services are needed in the community. First birth order and older mothers (>34 years) at time of death of infant were associated with significantly higher risk for mortality in this vil lage (p=0.004). Females were twice as likely as males to die in infancy (p=0.011), a finding which is contrary to what is gener ally found; there is a need for further studies to exclude gender discrimination in this village. Significantly more neonatal deaths occurred during the rainy season than in the dry season (p=0.018) suggesting that environmental factors play a role in neonatal deaths. In the neonatal period, the commonest cause of death was due to complications of low birth weight while in the postneonatal period it was due to infection. VHWs and TBAs are good resource persons for obtaining accurate numerical data at the grass-roots level, and the poten tial of using their services to collect vital but non-existant sta tistics should be explored. These workers also need to be trained to recognise factors that put infants at risk. Reassess ment of preventive strategies already implemented for reducing infant mortality may be required in order to further reduce the infant mortality rate in this community.