bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of culling on badger abundance: implications for tuberculosis control
Authors: Woodroffe R. , Gilks P. , Johnston W. T. , Le Fevre A. M. , Cox D. R. , Donnelly C. A. , Bourne F. J. , Cheeseman C. L. , Gettinby G. , McInerney J. P. , Morrison W. I.
Published: July 2007

Culling is often considered as a tool for controlling wildlife diseases that can also infect people or livestock. Culling European badgers Meles meles can cause both positive and negative effects on the incidence of bovine tuberculosis (TB) in cattle. One factor likely to influence the outcome of different badger‐culling strategies for cattle TB is the reduction in badger population density achieved. However, this reduction is difficult to measure because badgers, being nocturnal and fossorial, are difficult to count. Here, we use indices of badger abundance to measure the population impacts of two culling strategies tested in Britain. The densities of badger setts and latrines recorded before culling were correlated with the densities of badgers captured on initial culls, suggesting that both were indices of actual badger abundance. Widespread ‘proactive’ culling was associated with a 73% reduction in the density of badger latrines, a 69% reduction in the density of active burrows and a 73% reduction in the density of road‐killed badgers. This population reduction was achieved by a coordinated effort entailing widespread and repeated trapping over several years. However, this strategy caused only modest reductions in cattle TB incidence in culled areas and elevated incidence in neighbouring unculled areas. Localized ‘reactive’ culling caused a 26% reduction in latrine density, a 32% reduction in active burrow density and a 10% reduction in the density of road‐killed badgers, but apparently increased the incidence of cattle TB. These results indicate that the relationship between badger population reduction and TB transmission to cattle is strongly non‐linear, probably because culling prompts changes in badger behaviour that influence transmission rates. These findings raise serious questions about the capacity of badger culling to contribute to the control of cattle TB in Britain.
SELECTIVE ABORTION IN BRAZIL: THE ANENCEPHALY CASE
Authors: DINIZ DEBORA
Published: July 2007

This paper discusses the Brazilian Supreme Court ruling on the case of anencephaly. In Brazil, abortion is a crime against the life of a fetus, and selective abortion of non‐viable fetuses is prohibited. Following a paradigmatic case discussed by the Brazilian Supreme Court in 2004, the use of abortion was authorized in the case of a fetus with anencephaly. The objective of this paper is to analyze the ethical arguments of the case, in particular the strategy of avoiding the moral status of the fetus, the cornerstone thesis of the Catholic Church.
Haplotype analysis of signal peptide (insertion/deletion) and XbaI polymorphisms of the APOB gene in gallbladder cancer
Authors: Pandey Sachchida Nand , Srivastava Anvesha , Dixit Manjusha , Choudhuri Gourdas , Mittal B.
Published: July 2007

Purpose: The incidence of gallbladder cancer (GBC) is usually paralleled by the prevalence of gallstone disease, and genes of cholesterol metabolism have been implicated in gallstone disease. The XbaI and insertion/deletion (ins/del) polymorphism of Apolipoprotein B (APOB) appears to influence cholesterol homoeostasis and possibly risk for gallstone disease. We examined the effect of these polymorphisms individually as well as their haplotypes on GBC and gallstone patients in North Indian population.

Methods: The study comprises 123 consecutive cases of proven GBC, 172 cases of gallstone and 232 healthy subjects of similar age and sex. The genomic DNA was extracted from peripheral blood leucocytes and genotyping was performed using polymerase chain reaction (PCR) and PCR‐restriction fragment length polymorphism.

Results: In a case–control study, APOB XbaI and ins/del polymorphisms were not significantly associated with risk of GBC. Using the expectation maximization algorithm, four haplotypes were obtained, and haplotype X+,D was found to be significantly higher in GBC patients without stone in comparison with healthy subjects [odds ratio (OR) 2.9, 95% confidence interval 1.2–6.6 P=0.012].

Conclusions: The X+,D haplotype of APOB is associated with increased risk for development of GBC and the risk is not modified in the presence of gallstones.
Decline in the prevalence of dental fluorosis among South Australian children
Authors: Do L. G. , Spencer A. J.
Published: July 2007

Abstract –  Background:  The use of fluoride involves a balance between protection against dental caries and risk of dental fluorosis. Fluorosis in Australian children was highly prevalent in the early 1990s. Policy measures were introduced to control fluoride exposure so as to reduce the prevalence of fluorosis.

Objective:  To evaluate the effectiveness of policy measures in reducing the prevalence of fluorosis among Australian children.

Methods:  A random sample of South Australian children born in 1989–1994 was selected in 2002/2003, stratified by fluoridation status and urban/rural residence. Children were targeted to form three successive birth cohorts: those children born in 1989/1990, 1991/1992 and 1993/1994, respectively. Fluoride exposures were assessed by questionnaire. One dentist examined 677 children for fluorosis using the Thylstrup and Fejerskov (TF) Index. Data were reweighted to reflect the state's child population. Case definitions of fluorosis were: having a TF score of 1+ (TF1+) or a TF score of 2+ (TF2+) on one or both maxillary central incisors.

Results:  A higher proportion of children in the later birth cohorts used low‐concentration fluoridated toothpaste, and a smaller amount of toothpaste was used when they commenced toothbrushing. The fluorosis experience in this population was mostly very mild to mild. There was a significant decline in the prevalence of fluorosis across the three successive birth cohorts. The prevalence of fluorosis by TF1+ case definition declined from 34.7% to 22.1% and by TF2+ case definition from 17.9% to 8.3%. Risk factors for fluorosis were use of standard‐concentration fluoridated toothpaste, an eating and/or licking toothpaste habit and exposure to fluoridated water.

Conclusion:  The experience of fluorosis among the South Australian child population was mostly very mild to mild. There was a marked decline in the prevalence of fluorosis across the three successive birth cohorts. The decline was mainly linked with the reduction in exposure to fluoride from fluoridated toothpaste.
Life‐course epidemiology: concepts and theoretical models and its relevance to chronic oral conditions
Authors: Nicolau B. , Thomson W. M. , Steele J. G. , Allison P. J.
Published: July 2007

Abstract:  Etiological models that predominantly emphasize current adult life styles, such as smoking, diet and lack of exercise have recently been seriously challenged by a growing body of evidence that disturbed early growth and development, childhood infection, poor nutrition, and social and psychosocial disadvantage across the life‐course affect chronic disease risk, including chronic oral disease. This relatively new area of research is called life‐course epidemiology. The life‐course framework for investigating the aetiology and natural history of chronic disease proposes that advantages and disadvantages are accumulated throughout life generating differentials in health along the life‐course, but most importantly later in life. Furthermore, its dynamic framework brings together the effects of intrinsic factors (individual resources) with extrinsic factors (environmental factors). The aim of this paper is to give an overview of this new epidemiological approach and to discuss how the life‐course framework has been applied to chronic oral conditions.
Dental hygiene residential care in a 3‐year dental hygiene education programme in Japan: towards dysphagia management based on the dental hygiene process of care
Authors: Nishimura T , Takahashi C , Takahashi E
Published: July 2007

Abstract:  This paper reports an evaluation of a residential care practice, which was part of a ‘Dysphagia Management’ course introduced into a 3‐year dental hygiene curriculum in Japan. The clinical practice was performed at a care facility for the elderly people. Dental hygiene interventions, which consisted mainly of professional oral care, were implemented on a client who was bed‐bound after suffering from a stroke. As the client had severe tension in muscles around oral cavity, it was difficult for the facility care workers to provide daily oral hygiene care. The goals of the dental hygiene care plan included decreasing tension of oral muscles and reducing periodontal inflammation and halitosis. The dental hygiene interventions were given once a month for 5 months. Evaluation in the fifth month demonstrated relaxation of oral muscles, decrease in plaque accumulation, and improvements in levels of gingival inflammation, indicating the partial achievements of the initial goals. Possibilities for revision of the care plan could call for more active involvement of the facility care workers and client‐centered goal setting.

This learning experience provided an opportunity for continuing intervention and evaluation of dental hygiene care for the same client. The positive results of our limited interventions further confirmed the importance of professional oral care in organic and functional improvements in oral health for the elderly people.
The Internet and the oral healthcare professionals: potential and challenges of a new era
Authors: Mattheos N
Published: July 2007

Abstract:  The Internet is increasingly used as a means of continuous education for healthcare practitioners. At the same time, a rapidly growing number of patients rely on the Internet for the search and acquisition of healthcare‐related information and services. This fact has introduced new challenges for the oral healthcare personnel, which must not only often face the misperceptions of ill‐informed patients but also be able to redirect them to quality sources of healthcare‐related information.

Consequently, there is a great need for the whole oral healthcare team to further understand the potential and dangers of Internet‐based information.

The present paper aimed to briefly discuss the major implications of Internet use from two distinct points of view:

potential and risks of Internet use for lifelong learning and quality assessment of the oral healthcare team and

potential and dangers from the Internet as a means of patients’ education.

In particular this paper will review strategies of

generic Internet search;

search within healthcare‐related databases; and

principles quality assessment of information and resources.
Measurement of stain on extracted teeth using spectrophotometry and digital image analysis
Authors: Lath DL , Smith RN , Guan YH , Karmo M , Brook AH
Published: July 2007

Abstract:  Aim:  The aim of this study was to assess the reliability and validate a customized image analysis system, designed for use within clinical trials of general dental hygiene and whitening products, for the measurement of stain levels on extracted teeth and to compare it with reflectance spectrophotometry.

Method:  Twenty non‐carious extracted teeth were soaked in an artificial saliva, brushed for 1 min using an electric toothbrush and a standard toothpaste, bleached using a 5.3% hydrogen peroxide solution and cycled for 6 h daily through a tea solution. CIE L* values were obtained after each treatment step using the customized image analysis system and a reflectance spectrophotometer. A statistical analysis was carried out in SPSS.

Results:  Fleiss’ coefficient of reliability for intra‐operator repeatability of the image analysis system and spectrophotometry was 0.996 and 0.946 respectively. CIE L* values were consistently higher using the image analysis compared with spectrophotometry, and t‐tests for each treatment step showed significant differences (P < 0.05) for the two methods. Limits of agreement between the methods were −27.95 to +2.07, with a 95% confidence of the difference calculated as −14.26 to −11.84. The combined results for all treatment steps showed a significant difference between the methods for the CIE L* values (P < 0.05).

Conclusion:  The image analysis system has proven to be a reliable method for assessment of changes in stain level on extracted teeth. The method has been validated against reflectance spectrophotometry. This method may be used for pilot in vitro studies/trials of oral hygiene and whitening products, before expensive in vivo tests are carried out.
Systemic Distribution of West Nile Virus Infection: Postmortem Immunohistochemical Study of Six Cases
Authors: Armah Henry B. , Wang Guoji , Omalu Bennet I. , Tesh Robert B. , Gyure Kymberly A. , Chute Dennis J. , Smith Roger D. , Dulai Paul , Vinters Harry V. , Kleinschmidt‐DeMasters Bette K. , Wiley Clayton A.
Published: July 2007

Rare cases of West Nile virus (WNV)‐associated inflammation outside the central nervous system (CNS) have been reported. We evaluated the systemic distribution of WNV in postmortem tissues during encephalitis in six patients using immunohistochemistry. WNV antigens were detected in neurons of CNS (all 6 cases), kidney (4 cases), lungs (2 cases), pancreas (2 cases), thyroid (2 cases), intestine (2 cases), stomach (1 case), esophagus (1 case), bile duct (1 case), skin (1 case), prostate (1 case) and testis (1 case). In systemic organs epithelial cells were infected. In none of the six cases were viral antigens identified in hepatocytes, heart, adrenal gland, nerves, skeletal muscles, bone, vessels and fat. All cases in which viral antigens were identified in systemic organs in addition to CNS were severely immunocompromised transplant recipients. With the exception of testis and brain, most foci of infection were not associated with inflammation. While the absence of inflammation may in part be due to patient immunosuppression or to possible transient nature of any host response, compartmentalization of viral antigen to the luminal region of epithelial cells may sequester WNV from immune recognition. Comparison of our findings with previous reports suggests that patients with WNV encephalitis can have widespread systemic infection.
Longitudinal study of veterinary students and veterinarians: effects of growing up on a farm with animals
Authors: Heath TJ
Published: July 2007

Objective  To compare the career paths of veterinarians who had grown up on farms with animals with those of veterinarians from other backgrounds, during the first 15 years after they graduated.

Procedure  Questionnaires were completed by veterinary students in their first and fifth year, and after 1, 5, 10 and 15 years after they graduated. The most recent questionnaires were returned by 134 of 137 graduates, 20% of whom had grown up, or lived for at least two years, on farms where animals were a primary source of income. This paper includes findings from that questionnaire but also contains comparisons with previous ones.

Results  Fifteen years after they graduated, veterinarians who had grown up on farms with animals were more likely than those of other backgrounds to be living in centres with < 10,000 people (58% farm, 20% other), irrespective of the type of work they were doing. Although they were more likely to be doing no veterinary work (42% farm, 21% other), they were also more likely to be working in mixed practice (15% farm, 9% other) and with cattle and sheep generally (11% full time equivalent farm, 5% full time equivalent other). However, > 80% of those who had started their careers in mixed practice were no longer in mixed practice after 15 years. Veterinarians of farm origin who were in private practice were more likely to be sole or part owners (93% farm, 46% other) and less likely to be employees (7% farm, 54% other).

Conclusions  In this study, veterinarians who had grown up on farms with animals seemed slightly more likely than those from other backgrounds to continue working in mixed practice and to work with cattle or sheep, although the numbers were small and the differences not significant. Whatever their background, the majority who started their careers in mixed practice left over the next few years, and by 15 years only 15% remained.
Fucosylated fraction of alpha‐fetoprotein, L3, as a useful prognostic factor in patients with hepatocellular carcinoma with special reference to low concentrations of serum alpha‐fetoprotein
Authors: Kobayashi Makoto , Kuroiwa Takashi , Suda Takeshi , Tamura Yasushi , Kawai Hirokazu , Igarashi Masato , Fukuhara Yasuo , Aoyagi Yutaka
Published: July 2007

Background:  The aim of the present study was to establish L3 fraction before initial treatment as a useful prognostic factor in a prospective fashion in hepatocellular carcinoma (HCC) where the alpha‐fetoprotein (AFP) was very low.

Methods:  From 1990 to 2004, 298 HCC patients in whom L3 could be measured were examined in the present study. Enrolled patients with HCC underwent operation, transcatheter arterial chemoembolization and percutaneous ablation therapy. The current patient status was confirmed as of the end of March 2005. L3 was determined by crossed immuno‐affinoelectrophoresis when AFP was ≥30 ng/mL. It was carried out by liquid‐phase binding assay system on cases where AFP < 30 ng/mL. The tentative discriminating line of L3 was set at 15%.

Results:  The HCC group included four subgroups: 110 patients with AFP concentrations ≤100 ng/mL, 70 with AFP≤ 50 ng/mL, 38 with AFP ≤ 30 ng/mL and 29 with AFP ≤ 25 ng/mL. The mean survival rate in the HCC group, whose L3 was >15% (high L3), was significantly lower than that in the HCC group whose L3 was ≤15% (low L3). There were also statistically significant differences in survival rates between high and low L3 in the four HCC subgroups. The statistically significant differences were more distinct in the subgroups with low AFP concentrations.

Conclusions:  The present study indicates that the L3 fraction before treatment serves as a useful prognostic indicator when the serum concentrations of AFP were very low.
Validation of a Microsphere-Based Immunoassay for Detection of Anti-West Nile Virus and Anti-St. Louis Encephalitis Virus Immunoglobulin M Antibodies
Authors: Johnson Alison J. , Cheshier Ronald C. , Cosentino Giorgio , Masri Heather P. , Mock Valerie , Oesterle Rebecca , Lanciotti Robert S. , Martin Denise A. , Panella Amanda J. , Kosoy Olga , Biggerstaff Brad J.
Published: July 2007

A microsphere-based immunoassay (MIA) was previously developed that is capable of determining the presence of anti-West Nile (WN) virus or anti-St. Louis encephalitis (SLE) virus immunoglobulin M (IgM) antibodies in human serum or cerebrospinal fluid. The original data set on which the classification rules were based comprised 491 serum specimens obtained from the serum bank at the Division of Vector-Borne Infectious Diseases of the Centers for Disease Control and Prevention (DVBID). The classification rules were used to provide a result and to determine whether confirmatory testing was necessary for a given sample. A validation study was coordinated between the DVBID and five state health laboratories to determine (i) the reproducibility of the test between different laboratories, (ii) the correlation between the IgM-enzyme-linked immunosorbent assay (MAC-ELISA) and the MIA, and (iii) whether the initial nonspecific parameters could be refined to reduce the volume of confirmatory testing. Laboratorians were trained in the method, and reagents and data analysis software developed at the DVBID were shipped to each validating laboratory. Validating laboratories performed tests on approximately 200 samples obtained from their individual states, the collections of which comprised approximately equal numbers of WN virus-positive and -negative samples, as determined by MAC-ELISA. In addition, 377 samples submitted to the DVBID for arbovirus testing were analyzed using the MIA and MAC-ELISA at the DVBID only. For the specimens tested at both the state and the DVBID laboratories, a correlation of results indicated that the technology is readily transferable between laboratories. The detection of IgM antibodies to WN virus was more consistent than detection of IgM antibodies to SLE virus. Some changes were made to the analysis software that resulted in an improved accuracy of diagnosis.
Microsporidian Infection Is Prevalent in Healthy People in Cameroon
Authors: Nkinin Stephenson W. , Asonganyi Tazoacha , Didier Elizabeth S. , Kaneshiro Edna S.
Published: July 2007

Most studies of opportunistic infections focus on those with weak immune systems, such as human immunodeficiency virus (HIV)/AIDS patients and children. However, there is a lack of information on these infectious agents in healthy people worldwide. In the present study, stool samples from both HIV patients and healthy people were examined to begin filling in this serious gap in the understanding of human microsporidiosis, particularly the enteric parasite
Enterocytozoon bieneusi
. Specimens were obtained from 191 individuals living in Yaoundé, the capital city of Cameroon, in sub-Sahara Africa, including 28 HIV-positive patients who also had tuberculosis (TB).
E. bieneusi
prevalence was 35.7% among the HIV
+
TB patients, whereas it was only 24.0% among 25 HIV
−
TB patients in the same hospital. Unexpectedly, the prevalence (67.5%) of microsporidiosis was found to be even higher for 126 immunocompetent individuals than for those with TB (healthy people compared to HIV
+
TB and HIV
−
TB patients;
P
< 0.001). The immunocompetent group included people ranging from 2 to 70 years of age living in four different neighborhoods in Yaoundé. The highest prevalence (81.5%) was among teenagers, and the highest mean infection score (+2.5) was among children. Additional studies of immunocompetent people in other parts of Cameroon, as well as in other countries, are needed to better understand microsporidiosis epidemiology. There is still much more to be learned about the natural history of microsporidia, the pathogenicity of different strains, and the role of enteric microsporidia as opportunistic infections in immunodeficient people.
Bacteriology of Moderate-to-Severe Diabetic Foot Infections and In Vitro Activity of Antimicrobial Agents
Authors: Citron Diane M. , Goldstein Ellie J. C. , Merriam C. Vreni , Lipsky Benjamin A. , Abramson Murray A.
Published: July 2007

As part of a United States-based multicenter clinical trial, conducted from 2001 to 2004, that compared ertapenem to piperacillin-tazobactam for the treatment of moderate-to-severe diabetic foot infections (DFIs), we obtained 454 pretreatment specimens from 433 patients. After debridement, the investigators collected wound specimens, mostly by curettage or biopsy, and sent them to the R. M. Alden Research Laboratory for aerobic and anaerobic culture. Among the 427 positive cultures, 83.8% were polymicrobial, 48% grew only aerobes, 43.7% had both aerobes and anaerobes, and 1.3% had only anaerobes. Cultures yielded a total of 1,145 aerobic strains and 462 anaerobic strains, with an average of 2.7 organisms per culture (range, 1 to 8) for aerobes and 2.3 organisms per culture (range, 1 to 9) for anaerobes. The predominant aerobic organisms were oxacillin-susceptible
Staphylococcus aureus
(14.3%), oxacillin-resistant
Staphylococcus aureus
(4.4%), coagulase-negative
Staphylococcus
species (15.3%),
Streptococcus
species (15.5%),
Enterococcus
species (13.5%),
Corynebacterium
species (10.1%), members of the family
Enterobacteriaceae
(12.8%), and
Pseudomonas aeruginosa
(3.5%). The predominant anaerobes were gram-positive cocci (45.2%),
Prevotella
species (13.6%),
Porphyromonas
species (11.3%), and the
Bacteroides fragilis
group (10.2%). Pure cultures were noted for 20% of oxacillin-resistant
Staphylococcus aureus
cultures, 9.2% of
Staphylococcus epidermidis
cultures, and 2.5% of
P. aeruginosa
cultures. Two or more species of
Staphylococcus
were present in 13.1% of the patients. Ertapenem and piperacillin-tazobactam were each active against >98% of the enteric gram-negative rods, methicillin-sensitive
S. aureus
, and anaerobes. Among the fluoroquinolones, 24% of anaerobes, especially the gram-positive cocci, were resistant to moxifloxacin; 27% of the gram-positive aerobes but only 6% of the members of the family
Enterobacteriaceae
were resistant to levofloxacin. Moderate-to-severe DFIs are typically polymicrobial, and almost half include anaerobes. Our antibiotic susceptibility results can help to inform therapeutic choices.
Replication-Competent Variants of Human Immunodeficiency Virus Type 2 Lacking the V3 Loop Exhibit Resistance to Chemokine Receptor Antagonists
Authors: Lin George , Bertolotti-Ciarlet Andrea , Haggarty Beth , Romano Josephine , Nolan Katrina M. , Leslie George J. , Jordan Andrea P.-O. , Huang Chih-chin , Kwong Peter D. , Doms Robert W. , Hoxie James A.
Published: July 2007

Entry of human immunodeficiency virus type 1 (HIV-1) and HIV-2 requires interactions between the envelope glycoprotein (Env) on the virus and CD4 and a chemokine receptor, either CCR5 or CXCR4, on the cell surface. The V3 loop of the HIV gp120 glycoprotein plays a critical role in this process, determining tropism for CCR5- or CXCR4-expressing cells, but details of how V3 interacts with these receptors have not been defined. Using an iterative process of deletion mutagenesis and in vitro adaptation of infectious viruses, variants of HIV-2 were derived that could replicate without V3, either with or without a deletion of the V1/V2 variable loops. The generation of these functional but markedly minimized Envs required adaptive changes on the gp120 core and gp41 transmembrane glycoprotein. V3-deleted Envs exhibited tropism for both CCR5- and CXCR4-expressing cells, suggesting that domains on the gp120 core were mediating interactions with determinants shared by both coreceptors. Remarkably, HIV-2 Envs with V3 deletions became resistant to small-molecule inhibitors of CCR5 and CXCR4, suggesting that these drugs inhibit wild-type viruses by disrupting a specific V3 interaction with the coreceptor. This study represents a proof of concept that HIV Envs lacking V3 alone or in combination with V1/V2 that retain functional domains required for viral entry can be derived. Such minimized Envs may be useful in understanding Env function, screening for new inhibitors of gp120 core interactions with chemokine receptors, and designing novel immunogens for vaccines.
Induction of Potent CD8
+
T-Cell Responses by Novel Biodegradable Nanoparticles Carrying Human Immunodeficiency Virus Type 1 gp120
Authors: Wang Xin , Uto Tomofumi , Akagi Takami , Akashi Mitsuru , Baba Masanori
Published: July 2007

The mainstream of recent anti-AIDS vaccines is a prime/boost approach with multiple doses of the target DNA of human immunodeficiency virus type 1 (HIV-1) and recombinant viral vectors. In this study, we have attempted to construct an efficient protein-based vaccine using biodegradable poly(γ-glutamic acid) (γ-PGA) nanoparticles (NPs), which are capable of inducing potent cellular immunity. A significant expansion of CD8
+
T cells specific to the major histocompatibility complex class I-restricted gp120 epitope was observed in mice intranasally immunized once with gp120-carrying NPs but not with gp120 alone or gp120 together with the B-subunit of cholera toxin. Both the gp120-encapsulating and -immobilizing forms of NPs could induce antigen-specific spleen CD8
+
T cells having a functional profile of cytotoxic T lymphocytes. Long-lived memory CD8
+
T cells could also be elicited. Although a substantial decay in the effector memory T cells was observed over time in the immunized mice, the central memory T cells remained relatively constant from day 30 to day 238 after immunization. Furthermore, the memory CD8
+
T cells rapidly expanded with boosting with the same immunogen. In addition, γ-PGA NPs were found to be a much stronger inducer of antigen-specific CD8
+
T-cell responses than nonbiodegradable polystyrene NPs. Thus, γ-PGA NPs carrying various HIV-1 antigens may have great potential as a novel priming and/or boosting tool in current vaccination regimens for the induction of cellular immune responses.
Role of the Cytoplasmic Tail Domains of Bunyamwera Orthobunyavirus Glycoproteins Gn and Gc in Virus Assembly and Morphogenesis
Authors: Shi Xiaohong , Kohl Alain , Li Ping , Elliott Richard M.
Published: July 2007

The M RNA genome segment of Bunyamwera virus (BUNV), the prototype of the
Bunyaviridae
family, encodes a precursor polyprotein that is proteolytically cleaved to yield two structural proteins, Gn and Gc, and a nonstructural protein called NSm. Gn and Gc are type I integral transmembrane glycoproteins. The Gn protein contains a predicted cytoplasmic tail (CT) of 78 residues, and Gc has a shorter CT of 25 residues. Little is known about the role of the Gn and Gc CT domains in the virus replication cycle. We generated a series of mutant glycoprotein precursor constructs containing either deletions or alanine substitutions in the CT domains of Gn and Gc. We examined the effects of these mutations on glycoprotein maturation, cell surface expression, and low pH-induced syncytium formation. In addition, the effects of these mutations were also assessed using a reverse genetics-based virus assembly assay and a virus rescue system. Our results show that the CT domains of both Gn and Gc play crucial roles in BUNV-mediated membrane fusion, virus assembly, and morphogenesis.
The Role of WWP1-Gag Interaction and Gag Ubiquitination in Assembly and Release of Human T-Cell Leukemia Virus Type 1
Authors: Heidecker Gisela , Lloyd Patricia A. , Soheilian Ferri , Nagashima Kunio , Derse David
Published: July 2007

The PPPY motif in the matrix (MA) domain of human T-cell leukemia virus type 1 (HTLV-1) Gag associates with WWP1, a member of the HECT domain containing family of E3 ubiquitin ligases. Mutation of the PPPY motif arrests particle assembly at an early stage and abolishes ubiquitination of MA. Similar effects are seen when Gag is expressed in the presence of a truncated form of WWP1 that lacks the catalytically active HECT domain (C2WW). To understand the role of ubiquitination in budding, we mutated the four lysines in MA to arginines and identified lysine 74 as the unique site of ubiquitination. Virus-like particles produced by the K74R mutant did not contain ubiquitinated MA and showed a fourfold reduction in the release of infectious particles. Furthermore, the K74R mutation rendered assembly hypersensitive to C2WW inhibition; K74R Gag budding was inhibited at significantly lower levels of expression of C2WW compared with wild-type Gag. This finding indicates that the interaction between Gag and WWP1 is required for functions other than Gag ubiquitination. Additionally, we show that the PPPY
−
mutant Gag exerts a strong dominant-negative effect on the budding of wild-type Gag, further supporting the importance of recruitment of WWP1 to achieve particle assembly.
Interactions between Brome Mosaic Virus RNAs and Cytoplasmic Processing Bodies
Authors: Beckham Carla J. , Light Heather R. , Amar Nissan T. , Ahlquist Paul , Parker Roy , Noueiry Amine
Published: July 2007

Cytoplasmic processing bodies are sites where nontranslating mRNAs accumulate for different fates, including decapping and degradation, storage, or returning to translation. Previous work has also shown that the Lsm1-7p complex, Dhh1p, and Pat1p, which are all components of P bodies, are required for translation and subsequent recruitment to replication of the plant virus brome mosaic virus (BMV) genomic RNAs when replication is reproduced in yeast cells. To better understand the role of P bodies in BMV replication, we examined the subcellular locations of BMV RNAs in yeast cells. We observed that BMV genomic RNA2 and RNA3 accumulated in P bodies in a manner dependent on
cis
-acting RNA replication signals, which also directed nonviral RNAs to P bodies. Furthermore, the viral RNA-dependent RNA polymerase coimmunoprecipitates and shows partial colocalization with the P-body component Lsm1p. These observations suggest that the accumulation of BMV RNAs in P bodies may be an important step in RNA replication complex assembly for BMV, and possibly for other positive-strand RNA viruses.
Manipulation of the Toll-Like Receptor 7 Signaling Pathway by Epstein-Barr Virus
Authors: Martin Heather J. , Lee Jae Myun , Walls Dermot , Hayward S. Diane
Published: July 2007

Epstein-Barr virus (EBV) infection of primary B cells causes B-cell activation and proliferation. Activation of B cells requires binding of antigen to the B-cell receptor and a survival signal from ligand-bound CD40, signals that are provided by the EBV LMP1 and LMP2A latency proteins. Recently, Toll-like receptor (TLR) signaling has been reported to provide a third B-cell activation stimulus. The interaction between the EBV and TLR pathways was therefore investigated. Both UV-inactivated and untreated EBV upregulated the expression of TLR7 and downregulated the expression of TLR9 in naive B cells. UV-inactivated virus transiently stimulated naive B-cell proliferation in the presence of the TLR7 ligand R837, while addition of the TLR7 antagonist IRS 661 impaired cell growth induced by untreated EBV. Interferon regulatory factor 5 (IRF-5) is a downstream mediator of TLR7 signaling. IRF-5 was induced following EBV infection, and IRF-5 was expressed in B-cell lines with type III latency. Expression of IRF-5 in this setting is surprising since IRF-5 has tumor suppressor and antiviral properties. B-cell proliferation assays provided evidence that EBV modulates TLR7 signaling responses. Examination of IRF-5 transcripts identified a novel splice variant, V12, that was induced by EBV infection, was constitutively nuclear, and acted as a dominant negative form in IRF-5 reporter assays. IRF-4 negatively regulates IRF-5 activation, and IRF-4 was also present in type III latently infected cells. EBV therefore initially uses TLR7 signaling to enhance B-cell proliferation and subsequently modifies the pathway to regulate IRF-5 activity.
Preparticipation medical evaluation in professional sport in the UK: theory or practice?
Authors: Fuller C W , Ojelade E O , Taylor A
Published: July 2007

Objective:

To determine the level of pre-employment, pre-season, and post-injury medical evaluation of players undertaken within UK professional team sports.

Design:

A postal, whole population survey.

Setting:

Elite professional sports teams in England.

Population:

Six groups comprising the following clubs: professional football (Premiership, 15 of 20; Championship, 22 of 24), rugby union (Premiership, 9 of 12; Division 1, 11 of 14), rugby league (Super League, 6 of 11) and cricket (County, 12 of 18).

Main outcome measures:

Number (percentage) of clubs recording players’ medical history and undertaking medical examinations of players’ cardiovascular, respiratory, neurological, and musculoskeletal systems at pre-employment, pre-season and post-injury.

Results:

The overall response to the survey was 74%, with a range from 55% to 92% among groups. Almost 90% of football (Premiership and Championship) and rugby union (Premiership) clubs took a pre-employment history of players’ general health, cardiovascular, respiratory, neurological, and musculoskeletal systems, but fewer than 50% of cricket and rugby union (Division 1) clubs recorded a history. The majority of football (Premiership and Championship) and rugby union (Premiership) clubs implemented both cardiovascular and musculoskeletal examinations of players before employment. Fewer than 25% of clubs in any of the groups implemented neurological examinations of players at pre-employment, although 100% of rugby union (Premiership) and rugby league clubs implemented neurological testing during pre-season.

Conclusions:

None of the sports implemented best practice guidelines for the preparticipation evaluation of players at all stages of their employment. Departures from best practice guidelines and differences in practices between clubs within the same sport leave club physicians vulnerable if their players sustain injuries or ill health conditions that could have been identified and avoided through the implementation of a preparticipation examination.
A RENORMALIZATION PROOF OF THE KAM THEOREM FOR NON-ANALYTIC PERTURBATIONS
Authors: DE SIMONE EMILIANO
Published: July 2007

We shall use a Renormalization Group (RG) scheme in order to prove the classical KAM result in the case of a non-analytic perturbation (the latter will be assumed to have continuous derivatives up to a sufficiently large order). We shall proceed by solving a sequence of problems in which the perturbations are analytic approximations of the original one. We shall finally show that the sequence of the approximate solutions will converge to a differentiable solution of the original problem.
ABELIAN CONFORMAL FIELD THEORY AND DETERMINANT BUNDLES
Authors: ANDERSEN JØRGEN ELLEGAARD , UENO KENJI
Published: July 2007

Following [10], we study a so-called bc-ghost system of zero conformal dimension from the viewpoint of [14, 16]. We show that the ghost vacua construction results in holomorphic line bundles with connections over holomorphic families of curves. We prove that the curvature of these connections are up to a scale the same as the curvature of the connections constructed in [14, 16]. We study the sewing construction for nodal curves and its explicit relation to the constructed connections. Finally we construct preferred holomorphic sections of these line bundles and analyze their behaviour near nodal curves. These results are used in [4] to construct modular functors form the conformal field theories given in [14, 16] by twisting with an appropriate factional power of this Abelian theory.
TRIPLY-GRADED LINK HOMOLOGY AND HOCHSCHILD HOMOLOGY OF SOERGEL BIMODULES
Authors: KHOVANOV MIKHAIL
Published: July 2007

We consider a class of bimodules over polynomial algebras which were originally introduced by Soergel in relation to the Kazhdan–Lusztig theory, and which describe a direct summand of the category of Harish–Chandra modules for sl(n). Rouquier used Soergel bimodules to construct a braid group action on the homotopy category of complexes of modules over a polynomial algebra. We apply Hochschild homology to Rouquier's complexes and produce triply-graded homology groups associated to a braid. These groups turn out to be isomorphic to the groups previously defined by Lev Rozansky and the author, which depend, up to isomorphism and overall shift, only on the closure of the braid. Consequently, our construction produces a homology theory for links.
A HIERARCHY OF LATTICE SOLITON EQUATIONS AND ITS HIGHER-ORDER SYMMETRY CONSTRAINT
Authors: XU XI-XIANG , YANG HONG-XIANG
Published: July 2007

Starting from a discrete matrix spectral problem, a hierarchy of lattice soliton equations is derived through a discrete zero curvature representation. The Hamiltonian structures are established for the resulting hierarchy. Then the higher-order symmetry constraint for the resulting hierarchy is studied. It is shown that under the higher-order symmetry constraint, each lattice soliton equation in the resulting hierarchy can be factored by an integrable symplectic map and a finite-dimensional Liouville integrable Hamiltonian system.
DIAGNOSTICS OF COPPER PLASMA PRODUCED BY THE FUNDAMENTAL, SECOND AND THIRD HARMONICS OF A Nd:YAG LASER
Authors: RASHID B. , HAFEEZ S. , SHAIKH NEK M. , SALEEM M. , ALI R. , BAIG M. A.
Published: July 2007

We report measurements of the copper plasma parameters generated by the fundamental, second and third harmonics of a Nd:YAG laser. The 3 d94 s 5 s2D3/2→3 d94 s 4 p2F5/2at 464.25 nm, 4p2P3/2→3 d94 s2D5/2at 510.55 nm, 4d2D3/2→4 p2P1/2at 515.32 nm 4d2D5/2→4 p2P3/2at 521.82 nm and 4p2P3/2→3 d94 s2D3/2at 570.02 nm transitions have been used to estimate the electron temperature through the Boltzmann plot method. The number density has been estimated from the Stark broadened profiles of the spectral lines. The spatial behaviour of the electron temperature and number density has been examined at different ambient air pressures and with laser irradiance. The temperature and number density are found to be in the range from 14700 to 13600 K and 2.1×1016to 1.78×1016cm-3for the 1064 nm laser, from 14200 to 12800 K and 2.2×1016to 1.8×1016cm-3for the 532 nm laser and from 14100 to 12500 K and 2.4×1016to 1.9×1016cm-3for the 355 nm laser.
PAIR EXCITATIONS AND VERTEX CORRECTIONS IN FERMI FLUIDS AND THE DYNAMIC STRUCTURE FUNCTION OF TWO-DIMENSIONAL 3He
Authors: BÖHM H. M. , GODFRIN H. , KROTSCHECK E. , LAUTER H. J. , MESCHKE M. , PANHOLZER M.
Published: July 2007

We use the equations–of–motion approach for time–dependent pair correlations in strongly interacting Fermi liquids to develop a theory of the excitation spectrum and the single–particle self energy in such systems. We present here the fully correlated equations and their approximate solutions for 3 He . Our theory has the following properties: It reduces to both, i) the "correlated" random–phase approximation (RPA) for strongly interacting fermions if the two–particle–two–hole correlations are ignored, and, ii) to the correlated Brillouin–Wigner perturbation theory for boson quantum fluids in the appropriate limit. iii) It preserves the two first energy–weighted sum rules, and systematically improves upon higher ones. iv) A familiar problem of the standard RPA is that it predicts a roton energy that lies more than a factor of two higher than what is found in experiments. A popular cure for this is to introduce an effective mass in the Lindhard function. No such ad–hoc assumption is invoked in our work. We demonstrate that the inclusion of correlated pair–excitations improves the dispersion relation significantly. Finally, a novel form of the density response function is derived that arises from vertex corrections in the proper polarization.
NON-FERMI-LIQUID BEHAVIOR FROM THE FERMI-LIQUID APPROACH
Authors: KHODEL V. A. , CLARK J. W. , LI H. , YAKOVENKO V. M. , ZVEREV M. V.
Published: July 2007

Non-Fermi liquid behavior of strongly correlated Fermi systems is derived within the Landau approach. We attribute this behavior to a phase transition associated with a rearrangement of the Landau state that leads to flattening of a portion of the single-particle spectrum ∊(p) in the vicinity of the Fermi surface. We demonstrate that the quasiparticle subsystem responsible for the flat spectrum possesses the same thermodynamic properties as a gas of localized spins. Theoretical results compare favorably with available experimental data. While departing radically from prevalent views on the origin of non-Fermi-liquid behavior, the theory advanced here is nevertheless a conservative one of in continuing to operate within the general framework of Landau theory.
GROUND-STATE PROPERTIES OF SMALL 3He DROPS FROM QUANTUM MONTE CARLO SIMULATIONS
Authors: SOLA ESTER , CASULLERAS JOAQUIM , BORONAT JORDI
Published: July 2007

We present recent results from a diffusion Monte Carlo study of small 3 He drops in the limit of zero temperature. Using the same methodology than in previous calculations carried out for bulk 3 He , we have obtained accurate results for their energy and structure properties. A relevant concern of this analysis has been the determination of the stability threshold for self binding. Our results show that the smallest self-bound drop is formed by N = 30 atoms, with preferred orbitals for open shells corresponding to maximum value of the spin. The quality of the upper bound energies provided by the fixed node approximation is analyzed by performing released-node estimations for short released times. Possible improvements of the nodal surface by including BCS-like correlation functions are also discussed.
CONDENSATE FRACTION IN THE DYNAMIC STRUCTURE FUNCTION OF BOSE FLUIDS
Authors: SAARELA M. , MAZZANTI F. , APAJA V.
Published: July 2007

We present results on the behavior of the dynamic structure function in the short wave length limit using the equation of motion method. The one-body continuity equation defines the self-energy, which becomes a functional of the fluctuating two-body correlation function. We evaluate the self-energy in this limit and show that sum rules up to the second moment, which requires the self-energy in the short wave length limit and zero frequency to be proportional to the kinetic energy per particle, are exactly satisfied. We compare our results with the impulse approximation and calculate the condensate fraction. An analytic expression for the momentum distribution is also derived.
ELECTRON GAS IN HIGH-FIELD NANOSCOPIC TRANSPORT: METALLIC CARBON NANOTUBES
Authors: GREEN F. , NEILSON D.
Published: July 2007

Nanotube structures are unprecedented in their stability and current-carrying capacity at intense driving fields. A comprehensive understanding of electron conduction from equilibrium through to the high-driving-field regime is needed. We present a microscopically conserving quantum-kinetic description of transport for ohmically contacted carbon nanotubes. The approach is computationally straightforward and can describe nonequilibrium response over a wide range of parameters. We have analyzed the interplay of degeneracy and scattering dynamics on gate-controlled conduction in the one-dimensional channel, and have determined transconductances.
EVOLUTION AND DESTRUCTION OF THE KONDO EFFECT IN A CAPACITIVELY COUPLED DOUBLE DOT SYSTEM
Authors: LOGAN DAVID E. , GALPIN MARTIN R.
Published: July 2007

We consider the simplest example of a double quantum dot system: two equivalent, capacitively coupled single-level dots, each coupled to its own lead. Focussing on a regime of two electrons on the double dot, a rich range of behaviour is found on increasing the interdot coupling: first a crossover from spin- to charge-Kondo physics, via an intermediate SU(4) state with entangled spin and charge degrees of freedom; followed by a quantum phase transition of Kosterlitz-Thouless type to a non-Fermi liquid 'charge-ordered' phase with finite residual entropy and anomalous transport properties. The numerical renormalization group method, coupled with simple physical arguments, is employed to obtain a detailed understanding of the problem.
THE METHOD OF INCREMENTS — A WAVEFUNCTION-BASED AB-INITIO CORRELATION METHOD FOR SOLIDS
Authors: PAULUS BEATE
Published: July 2007

The method of increments is a wavefunction-based ab initio correlation method for solids, which explicitly calculates the many-body wavefunction of the system. After a Hartree-Fock treatment of the infinite system the correlation energy of the solid is expanded in terms of localised orbitals or of a group of localised orbitals. The method of increments has been applied to a great variety of materials with a band gap, but in this paper the extension to metals is described. The application to solid mercury is presented, where we achieve very good agreement of the calculated ground-state properties with the experimental data.
FRACTIONALLY CHARGED EXCITATIONS ON FRUSTRATED LATTICES
Authors: RUNGE E. , POLLMANN F. , FULDE P.
Published: July 2007

Systems of strongly correlated fermions on certain geometrically frustrated lattices at particular filling factors support excitations with fractional charges ±e/2. We calculate quantum mechanical ground states, low–lying excitations and spectral functions of finite lattices by means of numerical diagonalization. The ground state of the most thorough-fully studied case, the criss-crossed checkerboard lattice, is degenerate and shows long–range order. Static fractional charges are confined by a weak linear force, most probably leading to bound states of large spatial extent. Consequently, the quasi-particle weight is reduced, which reflects the internal dynamics of the fractionally charged excitations. By using an additional parameter, we fine–tune the system to a special point at which fractional charges are manifestly deconfined—the so–called Rokhsar–Kivelson point. For a deeper understanding of the low–energy physics of these models and for numerical advantages, several conserved quantum numbers are identified.