bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlation Between Sexual Function and Postrenal Transplant Quality of Life: Does Gender Matter?
Authors: Tavallaii Seyed Abbas , Fathi-Ashtiani Ali , Nasiri Mahmoud , Assari Shervin , Maleki Pouria , Einollahi Behzad
Published: August 2007

Introduction

Subjective health perceptions affect sexual function differently in males and females; such differences, however, have not hitherto been studied comprehensively in kidney-transplant recipients.

Aim

This study sought to investigate gender effect on the correlation between sexual function and quality-of-life (QOL) subdomains in kidney-transplant recipients by evaluating intercourse frequency (IF) and intercourse satisfaction (IS).

Methods

In a cross-sectional study, 124 married kidney-transplant recipients, who were randomly selected, were interviewed. The bivariate correlations between QOL subdomains, and IF and IS were analyzed with the Pearson test in the males and females, separately.

Main Outcome Measure

The IF and IS using the relationship and sexuality scale, and also the QOL using Short Form 36 (SF-36) were assessed.

Results

Sixty-seven subjects (54%) reported having no intercourse within the preceding months. Fifty subjects (40%) reported having no intercourse satisfaction. While IF and IS correlated with the total SF-36 score in the males (r =0.252 and 0.263, P <0.05), there was no such correlation in the females. In the males, IS correlated with physical health (r =0.281, P <0.05) and physical function (r =0.274, P <0.05), and there was a correlation between IF and role limitation due to emotional problems (r =0.250, P <0.05). In the females, whereas IF correlated with general health (r =0.372, P <0.05) and mental health (r =0.305, P <0.05), there was no correlation between IS and QOL subdomains (P  > 0.05).

Conclusion

Sexual function and satisfaction seem to be correlated with mental and physical health in female and male kidney-transplant recipients, respectively. Although in the two genders, both physical and mental health should be equally evaluated; improving of the sexual function may be better achieved through different approaches.
Effects of lifestyle intervention and metformin on weight management and markers of metabolic syndrome in obese adolescents
Authors: Harden Kelly A. , Cowan Patricia A. , Velasquez‐Mieyer Pedro , Patton Susan B.
Published: August 2007

Purpose: The purposes of this study are threefold: to determine what components of the metabolic syndrome are present in obese adolescents, to determine what differences exist in the effects of lifestyle intervention versus lifestyle intervention plus metformin on weight management and select markers of metabolic syndrome in obese adolescents, and to determine which factors predict weight loss in obese adolescents treated with lifestyle changes and metformin.

Data sources: The study was a secondary data analysis utilizing a retrospective chart review of 63 obese adolescents aged 11 through 18 who were treated for obesity at the LeBonheur Youth Lifestyle Clinic from January 1, 2000, through June 30, 2005. Lifestyle interventions included diet, exercise, and counseling. The medication utilized was metformin. Outcomes evaluated included body mass index, relative body mass index (RBMI), weight, waist and hip circumference, blood pressure, serum lipid levels, fasting plasma glucose, 2‐h oral glucose tolerance tests, and insulin levels. Changes in mean values between groups were evaluated using the General Linear Models procedure. Logistic regression was utilized to determine which factors might predict weight loss.

Conclusions: The metformin group (N= 37) tended to be heavier, older, and had more components of the metabolic syndrome than the nonmetformin group (N= 26). All components of the metabolic syndrome were present in both groups (overall prevalence 55%). Both groups had a downward trend in RBMI, a surrogate marker for weight loss, but only the metformin group had a significant loss in RBMI points from baseline to end. There was a trend toward better diastolic blood pressure at 6 months in the metformin group (p= 0.06), which was not seen in the nonmetformin group. The only predictors of weight loss were higher RBMI (those who were heavier lost more) and the absence of type 2 diabetes mellitus (type 2 DM) (those with type 2 DM were less likely to lose 10 or more points in RBMI).

Implications for practice: All components of the metabolic syndrome are present in obese adolescents. The use of lifestyle changes and lifestyle changes plus metformin both produce some degree of weight loss, but subjects on metformin in this study lost significantly more RBMI points than those on lifestyle changes alone. Subjects with type 2 DM are less likely to lose weight than those without type 2 DM. Larger studies and studies with subjects more representative of the general population need to be carried out to assist in the development of evidence‐based practice guidelines.
Prevalence and management of headache in a university undergraduate population
Authors: Curry Kim , Green Roger
Published: August 2007

Purpose: The purpose of this pilot study was to explore the incidence, morbidity, and management of headaches in university undergraduate students. The authors also explored choice of reliever medications for headaches in an effort to assess potential needs for patient education concerning effective headache management.

Data sources: Data were collected from a convenience sample of 104 students. The Headache Assessment Quiz was used to measure type and severity of headache and to collect data on symptom management.

Conclusions: A majority of students surveyed reported experiencing headaches of moderate to severe intensity. Sixty percent of respondents indicated that headaches interfered with their usual activities while 92.5% reported use of nonprescription relievers only for headache management. Knowledge of headache prevention and treatment is lacking in this age group.

Implications for practice: Headaches are a common symptom in the college age population. Further research is needed to determine the incidence of specific types of headaches. Primary care providers are challenged to address patient education in this population as well as to assist patients in properly diagnosing headache types.
GOVERNANCE INSTITUTIONS AND PRIVATE INVESTMENT: AN APPLICATION TO THE MIDDLE EAST AND NORTH AFRICA
Authors: AYSAN Ahmet Faruk , NABLI Mustapha Kamel , VÉGANZONÈS‐VAROUDAKIS Marie‐Ange
Published: August 2007

This paper addresses the issue of the low level of private investment in the Middle East and North Africa (MENA) region, with special emphasis on the role of governance. Based on the existing published reports, we categorize what types of governance institutions are more detrimental to entrepreneurial investments. We then estimate a simultaneous model of private investment and governance quality where economic policies concurrently explain both variables. Our empirical results show that governance plays a significant role in private investment decisions. This result is particularly true in the case of “administrative quality” in the form of control of corruption, bureaucratic quality, investment‐friendly profile of administration, law and order, as well as for “political stability.” Evidence in favor of “public accountability” is also found. Our estimations also stress that structural reforms like financial development, trade openness, and human development affect private‐investment decisions directly, and/or through their positive effect on governance.
DO MARKETS PENALIZE AGENCY CONFLICTS BETWEEN CONTROLLING AND MINORITY SHAREHOLDERS? EVIDENCE FROM CHILE
Authors: LEFORT Fernando , WALKER Eduardo
Published: August 2007

Using a sample of Chilean listed firms with widespread presence of economic conglomerates that use pyramid structures to control affiliated companies, we find that firms where controlling shareholders have higher coincidence between cash and control rights are persistently more valued by the market. We carefully check that our results are not driven by omitted variable biases and control for reverse causation using a feature of Chilean Corporations Law that provides an exogenous instrument for ownership concentration.
Overheard in the Halls: What Adolescents Are Saying, and What Teachers Are Hearing, About Health Issues
Authors: Cohall Alwyn T. , Cohall Renee , Dye Bonnie , Dini Sheila , Vaughan Roger D. , Coots Susan
Published: August 2007

Background:  Schools have long been recognized as an excellent place to offer health education and supportive services. Teachers are among the most important influences in the lives of school‐aged children and can provide valuable insight into the health issues important to adolescents. The purpose of this study was to examine the potential role general academic teachers may play in facilitating adolescent health promotion efforts.

Methods:  To determine what teachers think about the role of health promotion in schools and what tools and topics they would find most helpful as critical advisers to students, we administered a 28‐question survey at staff development meetings in 4 New York City schools.

Results:  Teachers agreed that schools were an important venue for discussing and providing health messages. More than half of those surveyed reported having overheard student discussions about health once a week or more, and 70% stated that they had been actively approached by students 1‐3 or more times per semester with reports of personal problems or health issues. Teachers expressed concern about their ability to handle student mental, behavioral, and reproductive health problems and desired additional staff development workshops to address these needs.

Conclusions:  Teachers felt that schools were important places to promote dialogue about health and accept the importance of playing a broader role in the lives of youth beyond education. To enhance the prospect of health‐promoting interactions between teachers and students, attention must be paid to developing the overall skill and comfort level of teachers with respect to adolescent health concerns.
Block Copolymer Assembly via Kinetic Control
Authors: Cui Honggang , Chen Zhiyun , Zhong Sheng , Wooley Karen L. , Pochan Darrin J.
Published: August 2007

Block copolymers consist of two or more chemically different polymer segments, or blocks, connected by a covalent linkage. In solution, amphiphilic blocks can self-assemble as a result of energetic repulsion effects between blocks. The degree of repulsion, the lengths of the block segments, and the selectivity of the solvent primarily control the resultant assembled morphology. In an ideal situation, one would like to be able to alter the morphology that forms without having to change the chemistry of the block copolymer. Through the kinetic manipulation of charged, amphiphilic block copolymers in solution, we are able to generate different nanoscale structures with simple block copolymer chemistry. The technique relies on divalent organic counter ions and solvent mixtures to drive the organization of the block copolymers down specific pathways into complex one-dimensional structures. Block copolymers are increasingly used as templating materials; thus, the ability to control the formation of specific patterns and structures is of growing interest and applicability.
Emerging Challenges in Regulatory T Cell Function and Biology
Authors: Sakaguchi Shimon , Powrie Fiona
Published: August 2007

Much progress has been made in understanding how the immune system is regulated, with a great deal of recent interest in naturally occurring CD4
+
regulatory T cells that actively engage in the maintenance of immunological self-tolerance and immune homeostasis. The challenge ahead for immunologists is the further elucidation of the molecular and cellular processes that govern the development and function of these cells. From this, exciting possibilities are emerging for the manipulation of regulatory T cell pathways in treating immunological diseases and suppressing or augmenting physiological immune responses.
The FERONIA Receptor-like Kinase Mediates Male-Female Interactions During Pollen Tube Reception
Authors: Escobar-Restrepo Juan-Miguel , Huck Norbert , Kessler Sharon , Gagliardini Valeria , Gheyselinck Jacqueline , Yang Wei-Cai , Grossniklaus Ueli
Published: August 2007

In flowering plants, signaling between the male pollen tube and the synergid cells of the female gametophyte is required for fertilization. In the
Arabidopsis thaliana
mutant
feronia
(
fer
), fertilization is impaired; the pollen tube fails to arrest and thus continues to grow inside the female gametophyte.
FER
encodes a synergid-expressed, plasma membrane–localized receptor-like kinase. We found that the FER protein accumulates asymmetrically in the synergid membrane at the filiform apparatus. Interspecific crosses using pollen from
Arabidopsis lyrata
and
Cardamine flexuosa
on
A. thaliana
stigmas resulted in a
fer
-like phenotype that correlates with sequence divergence in the extracellular domain of FER. Our findings show that the female control of pollen tube reception is based on a
FER
-dependent signaling pathway, which may play a role in reproductive isolation barriers.
The Source of Saturn's G Ring
Authors: Hedman Matthew M. , Burns Joseph A. , Tiscareno Matthew S. , Porco Carolyn C. , Jones Geraint H. , Roussos Elias , Krupp Norbert , Paranicas Chris , Kempf Sascha
Published: August 2007

The origin of Saturn's narrow G ring has been unclear. We show that it contains a bright arc located 167,495.6 ± 1.3 km from Saturn's center. This longitudinally localized material is trapped in a 7:6 corotation eccentricity resonance with the satellite Mimas. The cameras aboard the Cassini spacecraft mainly observe small (1 to 10 micrometers) dust grains in this region, but a sharp decrease in the flux of energetic electrons measured near this arc requires that it also contain larger (centimeter- to meter-sized) bodies whose total mass is equivalent to that of a ∼100-meter-wide ice-rich moonlet. Collisions into these bodies may generate dust, which subsequently drifts outward to populate the rest of the G ring. Thus, the entire G ring could be derived from an arc of debris held in a resonance with Mimas.
Immune-like Phagocyte Activity in the Social Amoeba
Authors: Chen Guokai , Zhuchenko Olga , Kuspa Adam
Published: August 2007

Social amoebae feed on bacteria in the soil but aggregate when starved to form a migrating slug. We describe a previously unknown cell type in the social amoeba, which appears to provide detoxification and immune-like functions and which we term sentinel (S) cells. S cells were observed to engulf bacteria and sequester toxins while circulating within the slug, eventually being sloughed off. A Toll/interleukin-1 receptor (TIR) domain protein, TirA, was also required for some S cell functions and for vegetative amoebae to feed on live bacteria. This apparent innate immune function in social amoebae, and the use of TirA for bacterial feeding, suggest an ancient cellular foraging mechanism that may have been adapted to defense functions well before the diversification of the animals.
Regulation of Homeostatic Chemokine Expression and Cell Trafficking During Immune Responses
Authors: Mueller Scott N. , Hosiawa-Meagher Karoline A. , Konieczny Bogumila T. , Sullivan Brandon M. , Bachmann Martin F. , Locksley Richard M. , Ahmed Rafi , Matloubian Mehrdad
Published: August 2007

The chemokines CCL21 and CXCL13 are immune factors that dictate homing and motility of lymphocytes and dendritic cells in lymphoid tissues. However, the means by which these chemokines are regulated and how they influence cell trafficking during immune responses remain unclear. We show that CCL21 and CXCL13 are transiently down-regulated within lymphoid tissues during immune responses by a mechanism controlled by the cytokine interferon-γ. This modulation was found to alter the localization of lymphocytes and dendritic cells within responding lymphoid tissues. As a consequence, priming of T cell responses to a second distinct pathogen after chemokine modulation became impaired. We propose that this transient chemokine modulation may help orchestrate local cellularity, thus minimizing competition for space and resources in activated lymphoid tissues.
Multicenter Comparison of Molecular Methods for Detection of
Legionella
spp. in Sputum Samples
Authors: Bencini M. A. , van den Brule A. J. C. , Claas E. C. J. , Hermans M. H. A. , Melchers W. J. G. , Noordhoek G. T. , Salimans M. M. M. , Schirm J. , Vink C. , van der Zee A. , Jansen R.
Published: August 2007

Legionellosis can be diagnosed by PCR using sputum samples. In this report, the methods of nine laboratories for 12 sputum samples with
Legionella pneumophila
and
Legionella longbeachae
are compared. We conclude that (i) liquefaction prevents PCR inhibition, (ii) the employed
mip
gene PCRs detected
L. pneumophila
only, and (iii) the 16S rRNA gene PCR detected both
Legionella
species and is preferred for the diagnosis of legionellosis.
Corynebacterium kutscheri
Infection of Skin and Soft Tissue following Rat Bite
Authors: Holmes Natasha E. , Korman Tony M.
Published: August 2007

Corynebacterium kutscheri
is a common bacterium isolated from the oral cavity of healthy mice and rats. We report the first well-documented case of
C. kutscheri
human infection which followed a rat bite. The microorganism was identified by conventional biochemical tests and confirmed by 16S rRNA gene sequence analysis.
First Isolations of
Segniliparus rugosus
from Patients with Cystic Fibrosis
Authors: Butler W. Ray , Sheils Catherine A. , Brown-Elliott Barbara A. , Charles Nadege , Colin Andrew A. , Gant Mary J. , Goodill John , Hindman Diane , Toney Sean R. , Wallace Richard J. , Yakrus Mitchell A.
Published: August 2007

We report three cases of the new genus
Segniliparus
isolated from patients with cystic fibrosis. All isolates were unambiguously identified by 16S rRNA gene sequencing as
Segniliparus rugosus
(GenBank accession no. AY 60892). Drug susceptibility results that may enhance treatment for cystic fibrosis patients with this opportunistic pathogen are presented.
Rapid Detection of Shiga Toxin-Producing
Escherichia coli
by Optical Immunoassay
Authors: Teel Louise D. , Daly Judy A. , Jerris Robert C. , Maul Diana , Svanas Gregory , O'Brien Alison D. , Park Choong H.
Published: August 2007

In a multi-health center study, a new rapid optical immunoassay (OIA) for the detection of Shiga toxin types 1 and 2, the BioStar OIA SHIGATOX kit (Inverness Medical Professional Diagnostics, Inc.), was used to prospectively screen 742 fresh fecal samples for Shiga toxins in parallel with the Premier enterohemorrhagic
Escherichia coli
(EHEC) kit (Meridian BioScience, Inc.) with and without enrichment of the specimens by incubation in MacConkey broth. Additionally, 85 previously tested frozen fecal samples were assessed as described above. All positive immunoassay results were confirmed by the Vero cell cytotoxicity assay. A further modification of the screening procedure was evaluated on 470 of the prospectively screened specimens. Swabs of growth from conventionally plated stool culture media were subjected to the OIA SHIGATOX, and results were compared with those obtained with the Premier EHEC kit following broth enrichment. Overall, the OIA SHIGATOX kit was significantly more sensitive than the Premier EHEC kit on fresh direct stool specimens (sensitivities, 96.8% and 83.9%, respectively;
P
< 0.05). The two assays performed equally well with each other on frozen and broth-enriched samples. The colony sweep method used in conjunction with the OIA kit was somewhat more effective at detection of Shiga toxins from growth on agar than the overnight broth enrichment procedure used with the Premier EHEC assay (sensitivities, 100% and 92%, respectively;
P
< 0.09). Overall, the OIA SHIGATOX kit provided rapid, easy-to-interpret results and was highly effective at detection of Shiga toxin-producing
E. coli
in fecal samples and overnight cultures.
Rapid Identification of Clinically Relevant
Enterococcus
Species by Fluorescence In Situ Hybridization
Authors: Wellinghausen Nele , Bartel Melanie , Essig Andreas , Poppert Sven
Published: August 2007

A fluorescence in situ hybridization assay for the rapid identification of clinically relevant enterococci (
Enterococcus faecalis, E. faecium, E. gallinarum
, the VanC-type resistance group) was developed and evaluated with 33 reference strains, 68 clinical isolates, and 58 positive blood cultures. All probes showed excellent sensitivities and specificities.
Factors Influencing Broth Microdilution Antimicrobial Susceptibility Test Results for Dalbavancin, a New Glycopeptide Agent
Authors: Rennie Robert P. , Koeth Laura , Jones Ronald N. , Fritsche Thomas R. , Knapp Cindy C. , Killian Scott B. , Goldstein Beth P.
Published: August 2007

Performance of antimicrobial susceptibility tests with new agents requires careful consideration of the properties of the antimicrobial to ensure that the tests are standardized, reproducible, and reflect the true potency of the drug. Dalbavancin is a new glycopeptide with potent activity against gram-positive bacterial species. The investigations described here demonstrated that methodologic modifications of procedures are necessary to ensure consistent test results, both for quality control and for routine testing of clinical isolates. Dimethyl sulfoxide is the preferred primary solvent. The addition of 0.002% polysorbate-80 (a surfactant) to dalbavancin-containing wells in the reference broth microdilution assay resulted in consistent and reproducible MIC results for three quality control strains:
Staphylococcus aureus
ATCC 29213,
Enterococcus faecalis
ATCC 29212, and
Streptococcus pneumoniae
ATCC 49619. The same degree of consistency was observed among clinical isolates of gram-positive bacterial species tested in several clinical laboratories. These results indicate that the addition of 0.002% (final concentration) of the surfactant in broth microdilution tests produces optimal dalbavancin MICs required for accurate and reproducible clinical laboratory tests, without untoward influences of substrate binding or media constituents.
Herpes Simplex Virus Type 1 Genomes Are Associated with ND10 Nuclear Substructures in Quiescently Infected Human Fibroblasts
Authors: Everett Roger D. , Murray Jill , Orr Anne , Preston Chris M.
Published: August 2007

Herpes simplex virus type 1 (HSV-1) genomes become associated with structures related to cellular nuclear substructures known as ND10 or promyelocytic leukemia nuclear bodies during the early stages of lytic infection. This paper describes the relationship between HSV-1 genomes and ND10 in human fibroblasts that maintain the viral genomes in a quiescent state. We report that quiescent HSV-1 genomes detected by fluorescence in situ hybridization (FISH) are associated with enlarged ND10-like structures, frequently such that the FISH-defined viral foci are apparently enveloped within a sphere of PML and other ND10 proteins. The number of FISH viral foci in each quiescently infected cell is concordant with the input multiplicity of infection, with each structure containing no more than a small number of viral genomes. A proportion of the enlarged ND10-like foci in quiescently infected cells contain accumulations of the heterochromatin protein HP1 but not other common markers of heterochromatin such as histone H3 di- or trimethylated on lysine residue 9. Many of the virally induced enlarged ND10-like structures also contain concentrations of conjugated ubiquitin. Quiescent infections can be established in cells that are highly depleted for PML. However, during the initial stages of establishment of a quiescent infection in such cells, other ND10 proteins (Sp100, hDaxx, and ATRX) are recruited into virally induced foci that are likely to be associated with HSV-1 genomes. These observations illustrate that the intimate connections between HSV-1 genomes and ND10 that occur during lytic infection also extend to quiescent infections.
High-Frequency Reversion of Geminivirus Replication Protein Mutants during Infection
Authors: Arguello-Astorga Gerardo , Ascencio-Ibáñez J. Trinidad , Dallas Mary Beth , Orozco Beverly M. , Hanley-Bowdoin Linda
Published: August 2007

The geminivirus replication protein AL1 interacts with retinoblastoma-related protein (RBR), a key regulator of the plant division cell cycle, to induce conditions permissive for viral DNA replication. Previous studies of tomato golden mosaic virus (TGMV) AL1 showed that amino acid L148 in the conserved helix 4 motif is critical for RBR binding. In this work, we examined the effect of an L148V mutation on TGMV replication in tobacco cells and during infection of
Nicotiana benthamiana
plants. The L148V mutant replicated 100 times less efficiently than wild-type TGMV in protoplasts but produced severe symptoms that were delayed compared to those of wild-type infection in plants. Analysis of progeny viruses revealed that the L148V mutation reverted at 100% frequency in planta to methionine, leucine, isoleucine, or a second-site mutation depending on the valine codon in the initial DNA sequence. Similar results were seen with another geminivirus, cabbage leaf curl virus (CaLCuV), carrying an L145A mutation in the equivalent residue. Valine was the predominant amino acid recovered from
N. benthamiana
plants inoculated with the CaLCuV L145A mutant, while threonine was the major residue in
Arabidopsis thaliana
plants. Together, these data demonstrated that there is strong selection for reversion of the TGMV L148V and CaLCuV L145A mutations but that the nature of the selected revertants is influenced by both the viral background and host components. These data also suggested that high mutation rates contribute to the rapid evolution of geminivirus genomes in plants.
Assembly of Hepatitis B Virus Envelope Proteins onto a Lentivirus Pseudotype That Infects Primary Human Hepatocytes
Authors: Chai Ning , Chang Ho Eun , Nicolas Emmanuelle , Gudima Severin , Chang Jinhong , Taylor John
Published: August 2007

This study demonstrates that the envelope proteins of hepatitis B virus (HBV) could be incorporated into the lipid membrane of lentivirus pseudotype particles. The assembly procedure was initiated by the transfection of 293T cells with three plasmids: (i) a human immunodeficiency virus (HIV) packaging construct, (ii) a transfer plasmid expressing a reporter gene, and (iii) a plasmid expressing large (L), middle (M), and small (S) HBV envelope proteins. After 2 days, hepatitis B surface antigen and the antigenic forms of L, M, and S were detected at the cell surface by flow cytometry. Also, virus particles that were able to infect cultured primary human hepatocytes (PHH) were released. Under optimal conditions, 50% of PHH could be infected. In addition, the susceptibility of PHH and the resistance of other cell types to the pseudotype particles were similar to those observed for HBV and hepatitis delta virus (HDV), which shares the same L, M, and S. Furthermore, the infection of PHH by the pseudotype was sensitive to known inhibitors of HBV and HDV entry. These findings of specific and efficient infection of hepatocytes could be applicable to liver-specific gene therapy and may help clarify the attachment and entry mechanism used by HBV and HDV.
The Poly(A) Binding Protein Is Internalized in Virus-Induced Vesicles or Redistributed to the Nucleolus during Turnip Mosaic Virus Infection
Authors: Beauchemin Chantal , Laliberté Jean-François
Published: August 2007

Poly(A) binding protein 2 (PABP2) of
Arabidopsis thaliana
was previously shown to interact with VPg-Pro of turnip mosaic virus (TuMV) and may consequently play an important role during infection. Subcellular fractionation experiments revealed that PABP2 was predominantly a cytoplasmic soluble protein in healthy plants. However, in TuMV-infected plants, a subpopulation of PABP2 was membrane associated or was localized in the nucleus. Confocal microscopy experiments indicated that PABP2 was partially retargeted to the nucleolus in the presence of TuMV VPg-Pro. In addition, the membrane association of PABP2 during TuMV infection resulted from the internalization of the host protein in 6K-VPg-Pro-induced vesicles, as shown by a combination of confocal microscopy and sucrose gradient fractionation experiments. This redistribution of an important translation initiation factor to the nucleolus and to membrane structure likely underlies two important processes of the TuMV replication cycle.
Enhancement of Murine Coronavirus Replication by Severe Acute Respiratory Syndrome Coronavirus Protein 6 Requires the N-Terminal Hydrophobic Region but Not C-Terminal Sorting Motifs
Authors: Netland Jason , Ferraro Debra , Pewe Lecia , Olivares Heidi , Gallagher Thomas , Perlman Stanley
Published: August 2007

Severe acute respiratory syndrome coronavirus encodes several accessory proteins of unknown function. We previously showed that one such protein, encoded by ORF6, enhanced the growth of mouse hepatitis virus in tissue culture cells and in mice. Protein 6 consists of an N-terminal hydrophobic peptide and a C-terminal region containing intracellular protein sorting motifs. Herein, we show that mutation of the hydrophobic region but not the sorting motifs affected the ability of protein 6 to enhance virus growth. Collectively, these results support the notion that the 6 protein interacts with membrane-bound viral replication or assembly machinery to directly enhance virus replication and virulence in animals.
Mapping and Characterization of the Primary and Anamnestic H-2
d
-Restricted Cytotoxic T-Lymphocyte Response in Mice against Human Metapneumovirus
Authors: Melendi Guillermina A. , Zavala Fidel , Buchholz Ursula J. , Boivin Guy , Collins Peter L. , Kleeberger Steven R. , Polack Fernando P.
Published: August 2007

Cytotoxic T lymphocytes (CTLs) are important for the control of virus replication during respiratory infections. For human metapneumovirus (hMPV), an H-2
d
-restricted CTL epitope in the M2-2 protein has been described. In this study, we screened the hMPV F, G, N, M, M2-1, and M2-2 proteins using three independent algorithms to predict H-2
d
CTL epitopes in BALB/c mice. A dominant epitope (GYIDDNQSI) in positions 81 to 89 of the antitermination factor M2-1 and a subdominant epitope (SPKAGLLSL) in N
307-315
were detected during the anti-hMPV CTL response. Passive transfer of CD8
+
T-cell lines against M2-1
81-89
and N
307-315
protected Rag1
−/−
mice against hMPV challenge. Interestingly, diversification of CTL targets to include multiple epitopes was observed after repetitive infections. A subdominant response against the previously described M2-2 epitope was detected after the third infection. An understanding of the CTL response against hMPV is important for developing preventive and therapeutic strategies against the virus.
THE CMB DIPOLE AND CIRCULAR GALAXY DISTRIBUTION
Authors: TOMOZAWA YUKIO
Published: August 2007

The validity of Hubble's law defies the determination of the center of the big bang expansion, even if it exists. Every point in the expanding universe looks like the center from which the rest of the universe flies away. In this paper, we show that the distri- bution of apparently circular galaxies is not uniform in the sky and that there exists a special direction in the universe in our neighborhood. The data is consistent with the assumption that the tidal force due to the mass distribution around the universe center causes the deformation of galactic shapes depending on its orientation and location relative to the center and our galaxy. Moreover, the CMB dipole data can also be associated with the center of the universe expansion, if the CMB dipole at the center of our supercluster is assumed to be due to Hubble flow. The location of the center is estimated from the CMB dipole data. The direction to the center from both sets of data is consistent and the distance to the center is computed from the CMB dipole data.
BIREFRINGENCE OF VACUUM IN THE PRESENCE OF A COUNTERPROPAGATING ELECTROMAGNETIC WAVE
Authors: PRAKASH RANJANA , SHUKLA PRAMILA
Published: August 2007

We show, both semi-classically as well as quantum–mechanically that the vacuum becomes birefringent in the presence of a counterpropagating light beam. For the KJ laser energy, this effect is not observable. However, with several Mega joule laser pulses, this effect will be detectable.
PASSIVE CONTROL OF HYPERCHAOTIC LORENZ SYSTEM AND CIRCUIT EXPERIMENTAL ON EWB
Authors: WANG FA-QIANG , LIU CHONG-XIN
Published: August 2007

Based on the property of a passive system, the essential conditions under which a hyperchaotic Lorenz system could be equivalent to a passive system via smooth state feedback are derived, making the minimum phase hyperchaotic Lorenz system globally asymptotically stabilized at zero and at any desired equilibrium points. The results of simulation on Matlab and the circuit experiment on EWB confirm the effectiveness of the proposed hyperchaos control method.
A BASIC INTRODUCTION TO QUANTITATIVE SEISMIC HAZARD ASSESSMENT
Authors: TROMP JEROEN
Published: August 2007

We provide an overview of some of the issues that need to be considered in the context of quantitative seismic hazard assessment. To begin with, one needs to inventory and characterize the major faults that could produce earthquakes that would impact the region of interest. Next, one needs a seismographic network that continually records ground motion throughout the region. Data from this network may be used to assess and locate seismicity, calibrate ground motion simulations, and to conduct seismic early-warning experiments. To assess the response of engineered structures to strong ground motion, seismographs should also be installed at various locations within such engineered structures, e.g., on bridges, overpasses, dams and in tall buildings. The ultimate goal would be to perform 'end-to-end' simulations, starting with the rupture on an earthquake fault, followed by the propagation of the resulting seismic waves from the fault to an engineered structure of interest, and concluding with an assessment of the response of this structure to the imposed ground motion. To facilitate accurate ground motion and end-to-end simulations, one needs to construct a detailed three-dimensional (3D) seismic model of the region of interest. In particular, one needs to assess the slowest shear-wave speeds within the sediments underlying the metropolitan area. Geological information, and, in particular, seismic reaction and refraction surveys are critical in this regard. In the context of end-to-end simulations, detailed numerical models of engineered structures of interest need to be constructed as well. Data recorded by the seismographic network and in engineered structures after small to moderate earthquakes may be used to assess and calibrate the seismic and engineering models based upon numerical simulations. Once the seismic and engineering models produce synthetic ground motion that match the observed ground motion reasonably well, one can perform simulations of hypothetical large earthquakes to assess anticipated strong ground motion and potential damage. Throughout this article we will use the Los Angeles and Taipei metropolitan areas as examples of how to approach quantitative seismic hazard assessment.
Electrochemical Generation of Green Rust using Electrocoagulation
Authors: Moreno Hector A. , Cocke David L. , Gomes Jewel A. , Morkovsky Paul , Parga Jose , Peterson Eric , Garcia C.
Published: August 2007

Green rusts are unstable compounds containing a mixture of ferrous and ferric hydroxides that belong to a family of minerals known as layered double hydroxides (LDH). They can be represented with the general formula [FeII(6-x) FeIIIx (OH)12] x+[Ax/n-*yH2O] x-, where A is an n-valent anion mainly Cl-, CO3-2 and SO4-2, and in which either the bivalent or the trivalent iron can be replaced for other trivalent or bivalent metal ions. Green rust was first identified and studied as a corrosion product later it was identified in soils and related to interactions between microbes and metals in soils. Green rusts have been shown to be highly reactive compounds that are useful in the reduction of organic compounds such as methachlor, of inorganic elements such as Chromium, Selenium and Uranium; Arsenic removal, and in the treatment of Acid mine drainage (AMD). Green rust has been synthesized combining Fe(II) and Fe(III), by air oxidation of FeCl2 and other methods. In this paper, the electrochemical generation of green rust, its characterization by X-ray Diffraction (XRD), and implications to electrocoagulation will be discussed
Precipitation of Calcium Carbonate on a Steel Cathode
Authors: Peraza Barrios Alejandro , Chapman Thomas W. , Meas Y.
Published: August 2007

The precipitation of calcium carbonate from water containing 3 mM CaCO3 has been studied on a rotating disk electrode made of 304 stainless steel. When the electrode is polarized at potentials where hydrogen is produced or dissolved oxygen is reduced, the reduction reaction raises the interfacial pH sufficiently to precipitate the carbonate. The effects of current density and modulation on the precipitation process have been examined. This paper reports on the nature of the precipitates formed. Depending on the experimental conditions, one may obtain calcite, vaterite or aragonite. A mathematical model has been developed to describe the transport phenomena in the boundary layer on the rotating disk electrode. This model takes into account convection, diffusion, and migration as well as the homogeneous ionic equilibria in order to estimate the degree of supersaturation at the surface.
Growth of Carbon, Boron Nitride and ZnO Nanotubes for Biosensors
Authors: Moscatello Jason P. , Wang Jiesheng , Ulmen Benjamin , Kayastha Vijaya K. , Xie Ming , Mensah Samuel L. , Wu Shun , Pandey Archana , Lee Chee H. , Prasad Abhishek , Yap Yoke Khin
Published: August 2007

Nanotubes have significant portions of their atoms located at the surfaces and represent the future of biological devices. With such small dimensions, sensitivities and applications previously impossible are being made real. Not all nanomaterials are currently at the same level of proficiency, however. Carbon nanotubes are a mature, easily grown and controlled nanostructure, but boron nitride and zinc oxide are still coming into their own. Yet progress in all three species of nanotubes is making applications easier than before.
Design and Fabrication of pH Sensitive Field-Effect Transistor for Microfluidics with an Integral Reference Electrode
Authors: Polk Brian J.
Published: August 2007

Lab-on-a-Chip (LOC) systems might enjoy more widespread commercialization if reliable and accurate electronic chemical sensors are more closely integrated with the microfluidic networks. In this work, an ion-sensitive field-effect transistor (ISFET) and an Ag/AgCl quasi-reference electrode were integrated with a polymeric surface-mounted microfluidic network in order to demonstrate electrochemical measurement of pH in the planar microfluidic format. The gate insulator of the n-type ISFET was an silicon oxide / silicon nitride stack (85 nm / 38 nm). At steady-state, the drain-to-reference voltage gave linear calibrations for flowing buffer solutions from pH 3 to pH 11 of approximately 63 mV per pH unit. The device was observed to be temperature sensitive; however step changes in pH as small as 0.26 pH unit were clearly resolved by the ISFET. The ISFET was shown to be a viable all-electronic pH sensor for planar microfluidics.
Electrochemical Study of Pharmacological Activity at Single Cells: Beta-lapachone Effect on Oxidative Stress of Macrophages
Authors: Ferreira Danielle , Goulart Marilia O. , Tapsoba Issa , Arbault Stephane , Amatore Christian
Published: August 2007

Beta-lapachone (1), a natural ortho-naphthoquinone, has been widely used for its large pharmacological activities, particularly against cancers. In the present study, amperometry at platinized carbon microelectrode was used to investigate the activity of (1), at different concentrations after various incubation times, on the oxidative bursts release of single macrophages. The results show that the presence of 0.1 to 100 µM of beta-lapachone, within one hour of incubation, leads to a decrease of reactive oxygen and nitrogen species release, comparatively to control. Conversely, when the incubation time increases (4 hours and more), the quantity of the species released in presence of 1 µM of (1) increases. Moreover, macrophage membranes became withered after 4 hours of incubation in presence of 10 µM of (1) and leading to cell death. These studies demonstrated the advantage of electrochemical methods for analyzing in real-time and quantitatively the effect of beta-lapachone on oxidative burst.
Influence of the Substituent on the Reactivity of Anilinoperezones. Analysis of the Influence of the C(12)-C(13) Double Bond
Authors: Bautista Jose Antonio , Frontana Carlos E. , Solano Peralta Alejandro , Reyes-Hernández C.I. , Cuevas Gabriel Eduardo , González-Martínez Ignacio , Aguilar-Martinez Martha
Published: August 2007

Voltammetric and spectroelectrochemical-ESR studies of the electro-reduction of Perezone and five substituted anilinoperezones (R = -H, -OCH3; -CH3; -CN, -Br) and their dihydroderivatives in acetonitrile were made. The results showed that in PZ and APZs the double bond at C(12)-C(13) can be involved with the quinone ring. The values of EpcI-EpaI of APZHs indicated a increase in the acidity of the -OH, caused by the lack of the double bond and the logical production of the hydroquinone. On the other hand, the values corresponding to APZs imply that their electro-reduction process would stop at the hydroquinone monoanion, what is in agreement with ESR data. This suggests that, in the radical dianion structure, the spin density at quinone ring changes by the presence or absence of the olefinic bond. However, the magnitude of these changes is very small, which suggests that the interaction present involves a small energy change between both structures
Heavy Metal Transfer Across an Interface Model System Assisted by Diazadibenzocrown Ethers
Authors: Velazquez-Manzanares Miguel , Guerrero-Trejo Gabriela , Aguilar Julio C. , Amador-Hernández Judith
Published: August 2007

Two diazadibenzocrown ethers (4,10-diazadibenzo-18-crown-6 and 4,10-diazadi(4'-tert-butylbenzo)-18-crown-6) have been studied as Pb2+, Cd2+ and Zn2+ carriers across the interface between two immiscible electrolyte solutions by cyclic and square wave voltammetry. These two ionophores were useful in assisting Pb2+, Cd2+ and Zn2+ transfer across the water/1,2- dichloroethane interface in reversible ion transfer processes. The facilitated transport of Pb2+ across this interface is easier than the transfer of the other two metal ions studied regarding the energetic of the two different ionophore facilitated processes. These properties make possible to use these hydrophobic ligands as extractants in solvent extraction systems as well as to mimicking the heavy metal transfer across biological membranes.
Metallic Interaction Effects on the Reactivity of Lawsone Semiquinones
Authors: Frontana Carlos E. , Valle Grettel , Ugalde-Saldívar Víctor Manuel , González Ignacio
Published: August 2007

An electrochemical analysis of the reduction processes of the associated anion of Lawsone (Lw-) with different metallic ions proves that, no only the energetics of the electron transfer processes are different, but also the stability of the electrogenerated intermediates. This provokes a change in the reduction mechanism occurring for the studied MLw2Py2 complexes at the first reduction signal, where the reduction of the associated Lw- and the Py species occur. The corresponding radical anions are only detectable for the ZnLw2Py2 complex, as the metallic ion lacks of free electrons capable to couple with the unpaired spins of both radical species. However, this does not seem to affect the properties of the second reduction process observed for this type of compounds, where the reduction of the free conjugated base occurs, generaring a stable radical dianion. The origin of this free anion is still under investigations, but the obtained results show some insights on how does metal-lawsone complexation can modify the solution reactivity and stability of the electrogenerated radical anions.
Sphingosine 1-phosphate rapidly increases endothelial barrier function independently of VE-cadherin but requires cell spreading and Rho kinase
Authors: Xu Mei , Waters Chris L. , Hu Chuan , Wysolmerski Robert B. , Vincent Peter A. , Minnear Fred L.
Published: August 2007

Sphingosine 1-phosphate (S1P) rapidly increases endothelial barrier function and induces the assembly of the adherens junction proteins vascular endothelial (VE)-cadherin and catenins. Since VE-cadherin contributes to the stabilization of the endothelial barrier, we determined whether the rapid, barrier-enhancing activity of S1P requires VE-cadherin. Ca2+-dependent, homophilic VE-cadherin binding of endothelial cells, derived from human umbilical veins and grown as monolayers, was disrupted with EGTA, an antibody to the extracellular domain of VE-cadherin, or gene silencing of VE-cadherin with small interfering RNA. All three protocols caused a reduction in the immunofluorescent localization of VE-cadherin at intercellular junctions, the separation of adjacent cells, and a decrease in basal endothelial electrical resistance. In all three conditions, S1P rapidly increased endothelial electrical resistance. These findings demonstrate that S1P enhances the endothelial barrier independently of homophilic VE-cadherin binding. Junctional localization of VE-cadherin, however, was associated with the sustained activity of S1P. Imaging with phase-contrast and differential interference contrast optics revealed that S1P induced cell spreading and closure of intercellular gaps. Pretreatment with latrunculin B, an inhibitor of actin polymerization, or Y-27632, a Rho kinase inhibitor, attenuated cell spreading and the rapid increase in electrical resistance induced by S1P. We conclude that S1P rapidly closes intercellular gaps, resulting in an increased electrical resistance across endothelial cell monolayers, via cell spreading and Rho kinase and independently of VE-cadherin.
Macrorheology and adaptive microrheology of endothelial cells subjected to fluid shear stress
Authors: Dangaria Jhanvi H. , Butler Peter J.
Published: August 2007

Vascular endothelial cells (ECs) respond to temporal and spatial characteristics of hemodynamic forces by alterations in their adhesiveness to leukocytes, secretion of vasodilators, and permeability to blood-borne constituents. These physiological and pathophysiological changes are tied to adaptation of cell mechanics and mechanotransduction, the process by which cells convert forces to intracellular biochemical signals. The exact time scales of these mechanical adaptations, however, remain unknown. We used particle-tracking microrheology to study adaptive changes in intracellular mechanics in response to a step change in fluid shear stress, which simulates both rapid temporal and steady features of hemodynamic forces. Results indicate that ECs become significantly more compliant as early as 30 s after a step change in shear stress from 0 to 10 dyn/cm2 followed by recovery of viscoelastic parameters within 4 min of shearing, even though shear stress was maintained. After ECs were sheared for 5 min, return of shear stress to 0 dyn/cm2 in a stepwise manner did not result in any further rheological adaptation. Average vesicle displacements were used to determine time-dependent cell deformation and macrorheological parameters by fitting creep function to a linear viscoelastic liquid model. Characteristic time and magnitude for shear-induced deformation were 3 s and 50 nm, respectively. We conclude that ECs rapidly adapt their mechanical properties in response to shear stress, and we provide the first macrorheological parameters for time-dependent deformations of ECs to a physiological forcing function. Such studies provide insight into pathologies such as atherosclerosis, which may find their origins in EC mechanics.