bluuebunny/crossref_metadata_2025 huggingface dataset:
Is Photosensitive Epilepsy Less Common in Males Due to Variation in X Chromosome Photopigment Genes?
Authors: Taylor Isabella , Hodgson Bree , Scheffer Ingrid E. , Mulley John , Berkovic Samuel F. , Dibbens Leanne
Published: May 2007

Summary:  Photosensitive epilepsy is less frequent among males than females. Red is the most epileptogenic color. The X‐linked red pigment gene contains the polymorphism Ser180Ala; the Ser180 allele increases red sensitivity. We hypothesized that the paucity of males with photosensitive epilepsy is explained by the distribution of this sex‐linked allele, and predicted photosensitive males would have a low frequency of this allele. We genotyped 35 males with photosensitive epilepsy and 84 male controls. Allele frequencies did not differ between these groups. The hypothesis was not supported, so alternate reasons for the sex bias in photosensitive epilepsy must be sought.
Dentate Filter Function Is Altered in a Proepileptic Fashion during Aging
Authors: Patrylo Peter R. , Tyagi Isha , Willingham Amy L. , Lee Sung , Williamson Anne
Published: May 2007

Summary:  Purpose: The elderly have an increased incidence and prevalence for seizure disorders. Further, since up to 50% of these cases have no identifiable antecedent, it has been hypothesized that aging of the central nervous system itself may be epileptogenic. Aged rats, compared to adults, exhibit a greater susceptibility to and severity of seizures associated with hippocampal activation. Whether this aging‐related change reflects proconvulsive changes in limbic circuitry is unknown and thus was the focus of this study.

Methods: Hippocampal slices from adult and aged Fischer 344 rats were examined using electrophysiological techniques. The dentate gyrus was our model region since it is involved with both wet‐dog shakes and limbic seizures, and it is affected preferentially with age.

Results: No differences were noted between groups in field potential activity elicited with low frequency stimulation. In contrast, 5‐Hz molecular layer stimulation could evoke multiple population spikes in approximately 40% of aged versus 0% of adult slices. Further, recording in CA3 revealed that this stimulation paradigm could elicit multiple spikes in aged, but not adult, slices that frequently evolved into spontaneous epileptiform bursts. This change in the capacity of the dentate to respond to and filter afferent input was associated with an aging‐related decrease in the frequency of spontaneous IPSPs and an increased propensity for large amplitude prolonged EPSPs following disinhibition.

Conclusions: These epileptogenic changes in dentate function and circuitry could contribute to the exacerbated susceptibility for hippocampal seizures in aged rodents, as well as the aging‐related decline in spatial learning and memory.
Psychosocial factors and early childhood caries among low‐income African–American children in Detroit
Authors: Finlayson Tracy L. , Siefert Kristine , Ismail Amid I. , Sohn Woosung
Published: May 2007

Objectives:  This study sought to advance knowledge of the social determinants of oral health, by examining how several specific maternal health beliefs, behaviors, and psychosocial factors relate to young children's early childhood caries (ECC) status in a lower‐income African–American population.

Methods:  Data were collected by the Detroit Dental Health Project (NIDCR grant), a population‐based study of 1021 African–American families with at least one child under 6 years of age and living in 39 low‐income Census tracts in Detroit, Michigan. Analyses were limited to 719 children aged 1–5 years and their biological mothers, and conducted in SUDAAN to account for the complex sampling design. Survey data included health belief scales on mothers’ self‐efficacy, feelings of fatalism, knowledge about appropriate bottle use and children's oral hygiene needs, brushing habits, psychosocial measures of depressive symptoms (CES‐D), parenting stress, and availability of instrumental social support. The child's age, dental insurance status, dental visit history, and 1‐week brushing frequency were also included in the model. Children's ECC status, based on a dental examination, was the main outcome. The dental team used the International Caries Detection and Assessment System (ICDAS) criteria for caries detection. Each child was classified as either caries‐free or having ECC or severe ECC (S‐ECC) based on the case definition of ECC proposed by an expert panel for research purposes with preschool‐aged children.

Results:  The dental team followed a specific examination protocol and established reliable and consistent ratings of ECC based on the ICDAS criteria. The inter‐rater reliability kappa was 0.83 overall, and the intra‐rater reliability kappa was 0.74 overall. One‐third of the children had ECC, and 20% had severe ECC. Age of the child and lower parenting stress scores were each positively associated with ECC, while higher education and income were protective. Maternal oral health fatalism and knowledge of children's hygiene needs were associated with ECC among preschool‐aged children. ECC was higher among younger children who had past restorative care.

Conclusions:  These findings call attention to the high prevalence of ECC in this population and the need to consider psychosocial as well as traditional risk factors in developing interventions to reduce oral health disparities.
EFFECT OF ASCORBIC ACID WITH TUMBLING ON LIPID OXIDATION OF PRECOOKED ROAST BEEF1
Authors: CHENG EN‐HUA , OCKERMAN HERBERT W.
Published: May 2007

Lipid oxidation causes off‐ and rancid flavors that are serious problems during storage of fresh meat and precooked beef products. The objective of this study was to evaluate ascorbic acid with tumbling for retarding lipid oxidation in precooked roast beef. The sample without ascorbic acid had a significantly higher pH value compared to products with different ascorbic acid levels when stored up to day 7. The pH of roast beef was primarily dependent on the levels of ascorbic acid added. Tumbling did not influence lipid oxidation, but it caused roast beef to be more tender. However, there was a decrease in lipid oxidation with increased concentrations of ascorbic acid. Due to unsealed packuging, the release of moisture increased over storage time. The nonheme iron values were significantly increased at day 7 compared to day 0. The injection of 5000 ppm of ascorbic acid inhibited bacterial growth in refrigerated storage.
Long Persistence of Methicillin-Susceptible Strains of
Staphylococcus aureus
Causing Sepsis in a Neonatal Intensive Care Unit
Authors: Gomez-Gonzalez Carmen , Alba Concepción , Otero Joaquín R. , Sanz Francisca , Chaves Fernando
Published: May 2007

Molecular epidemiology of
Staphylococcus aureus
strains causing bacteremia in neonates during 2002 to 2005 revealed seven clones, with four MSSA clones responsible for 80% of the cases. Some clones persisted or reappeared throughout the study. Three bacteremic clones were found colonizing health care workers (HCWs), particularly clone C, which was harbored by at least 15% of HCWs.
Molecular Characterization of Methicillin-Resistant
Staphylococcus aureus
Isolates Collected in Asunción, Paraguay
Authors: Mayor Lys , Ortellado Juana , Menacho Carmen , Lird Graciela , Courtier Christine , Gardon Christine , Meugnier Hélène , Bes Michèle , Vandenesch François , Etienne Jerome
Published: May 2007

We characterized 34 methicillin-resistant
Staphylococcus aureus
strains isolated in Paraguay in 2005. The strains belonged to two clones. The major clone (sequence type 5 [ST5] or ST221,
spa
type t149, staphylococcal cassette chromosome
mec
[SCC
mec
] type I) was similar to the Cordobes/Chilean clone spreading through South America, and the minor clone (ST239 or ST889,
spa
type t037, SCC
mec
type IIIA) was related to the Brazilian clone.
Leptotrichia amnionii, an Emerging Pathogen of the Female Urogenital Tract
Authors: Thilesen Carina M. , Nicolaidis Mikael , Lökebö Jan Eirik , Falsen Enevold , Jorde Anne Tomine , Müller Fredrik
Published: May 2007

Leptotrichia amnionii, a recently described, very fastidious, gram-negative anaerobic bacterium, is an opportunistic pathogen of the female urogenital tract. We report a case of second-trimester abortion in a patient with chorioamnionitis andL. amnioniibacteremia and a case of renal abscess in a female 5 weeks postpartum.
Limited Applicability of Direct Fluorescent-Antibody Testing for
Bordetella
sp. and
Legionella
sp. Specimens for the Clinical Microbiology Laboratory
Authors: She Rosemary C. , Billetdeaux Erick , Phansalkar Amit R. , Petti Cathy A.
Published: May 2007

The rapid diagnosis of infections with
Bordetella
and
Legionella
species is important for patient management. With observed increases in direct fluorescent-antibody (DFA) testing volumes, we retrospectively compared the performance characteristics of DFA testing to those of culture and PCR. For
Bordetella
sp., samples were classified as positive by DFA testing (184 [3%] of 6,195 samples) and culture (150 [2%] of 6,251 samples) significantly less often than by PCR (2,557 [10%] of 26,929 samples). Of 360 samples tested by both DFA and PCR methods, 81 (16 by DFA testing and 79 by PCR) were determined to be positive for
Bordetella
, with a sensitivity and specificity of DFA testing of 18% and 99%, respectively. Of 1,426 samples tested by both DFA and culture methods, 48 (44 by DFA testing and 15 by culture) were determined to be positive for
Bordetella
, with a sensitivity and specificity of DFA testing of 73% and 98%, respectively. For
Legionella
sp., samples were identified as positive by DFA testing (31 [0.25%] of 12,597 samples) and culture (85 [0.6%] of 13,572 samples) significantly less often than by PCR (27 [4%] of 716 samples). Of 62 samples tested by both DFA and PCR methods, none were positive for
Legionella
sp. by DFA testing and 3 were positive by PCR. Of 3,923 samples tested by both DFA and culture methods, 22 (3 by DFA testing and 21 by culture) were positive for
Legionella
sp., with a sensitivity and specificity of DFA testing of 9.5% and 100%. Overall, DFA testing for
Bordetella
sp. and
Legionella
sp. is an insensitive method, and despite its continued popularity, clinical microbiology laboratories should not offer it when more sensitive tests like PCR are available.
Prophage Sequences Defining Hot Spots of Genome Variation inSalmonella entericaSerovar Typhimurium Can Be Used To Discriminate between Field Isolates
Authors: Cooke Fiona J. , Wain John , Fookes Maria , Ivens Alasdair , Thomson Nicholas , Brown Derek J. , Threlfall E. John , Gunn George , Foster Geoffrey , Dougan Gordon
Published: May 2007

Sixty-oneSalmonella entericaserovar Typhimurium isolates of animal and human origin, matched by phage type, antimicrobial resistance pattern, and place of isolation, were analyzed by microbiological and molecular techniques, including pulsed-field gel electrophoresis (PFGE) and plasmid profiling. PFGE identified 10 profiles that clustered by phage type and antibiotic resistance pattern with human and animal isolates distributed among different PFGE profiles. Genomic DNA was purified from 23 representative strains and hybridized to the compositeSalmonellaDNA microarray, and specific genomic regions that exhibited significant variation between isolates were identified. Bioinformatic analysis showed that variable regions of DNA were associated with prophage-like elements. Subsequently, simple multiplex PCR assays were designed on the basis of these variable regions that could be used to discriminate betweenS. entericaserovar Typhimurium isolates from the same geographical region. These multiplex PCR assays, based on prophage-like elements andSalmonellagenomic island 1, provide a simple method for identifying new variants ofS. entericaserovar Typhimurium in the field.
Erythrocyte Binding Preference of Avian Influenza H5N1 Viruses
Authors: Louisirirotchanakul Suda , Lerdsamran Hatairat , Wiriyarat Witthawat , Sangsiriwut Kantima , Chaichoune Kridsda , Pooruk Phisanu , Songserm Taweesak , Kitphati Rungrueng , Sawanpanyalert Pathom , Komoltri Chulaluk , Auewarakul Prasert , Puthavathana Pilaipan
Published: May 2007

Five erythrocyte species (horse, goose, chicken, guinea pig, and human) were used to agglutinate avian influenza H5N1 viruses by hemagglutination assay and to detect specific antibody by hemagglutination inhibition test. We found that goose erythrocytes confer a greater advantage over other erythrocyte species in both assays.
The H5N1 Influenza Virus NS Genes Selected after 1998 Enhance Virus Replication in Mammalian Cells
Authors: Twu Karen Y. , Kuo Rei-Lin , Marklund Jesper , Krug Robert M.
Published: May 2007

The NS1A proteins of human influenza A viruses bind CPSF30, a cellular factor required for the processing of cellular pre-mRNAs, thereby inhibiting the production of all cellular mRNAs, including beta interferon mRNA. Here we show that the NS1A protein of the pathogenic H5N1 influenza A/Hong Kong/483/97 (HK97) virus isolated from humans has an intrinsic defect in CPSF30 binding. It does not bind CPSF30 in vitro and causes high beta interferon mRNA production and reduced virus replication in MDCK cells when expressed in a recombinant virus in which the other viral proteins are encoded by influenza A/Udorn/72. We traced this defect to the identities of amino acids 103 and 106 in the HK97 NS1A protein, which differ from the consensus amino acids, F and M, respectively, found in the NS1A proteins of almost all human influenza A virus strains. X-ray crystallography has shown that F103 and M106, which are not part of the CPSF30 binding pocket of the NS1A protein, stabilize the NS1A-CPSF30 complex. In contrast to the HK97 NS1A protein, the NS1A proteins of H5N1 viruses isolated from humans after 1998 contain F103 and M106 and hence bind CPSF30 in vitro and do not attenuate virus replication. The HK97 NS1A protein is less attenuating when expressed in a virus that also encodes the other internal HK97 proteins and under these conditions binds to CPSF30 to a substantial extent in vivo. Consequently, these internal HK97 proteins largely compensate for the absence of F103 and M106, presumably by stabilizing the NS1A-CPSF30 complex.
Adaptation of Borna Disease Virus to New Host Species Attributed to Altered Regulation of Viral Polymerase Activity
Authors: Ackermann Andreas , Staeheli Peter , Schneider Urs
Published: May 2007

Borna disease virus (BDV) can persistently infect the central nervous system of a broad range of mammalian species. Mice are resistant to infections with primary BDV isolates, but certain laboratory strains can be adapted to replicate in mice. We determined the molecular basis of adaptation by studying mutations acquired by a cDNA-derived BDV strain during one brain passage in rats and three passages in mice. The adapted virus propagated efficiently in mouse brains and induced neurological disease. Its genome contained seven point mutations, three of which caused amino acid changes in the L polymerase (L1116R and N1398D) and in the polymerase cofactor P (R66K). Recombinant BDV carrying these mutations either alone or in combination all showed enhanced multiplication speed in Vero cells, indicating improved intrinsic viral polymerase activity rather than adaptation to a mouse-specific factor. Mutations R66K and L1116R, but not N1398D, conferred replication competence of recombinant BDV in mice if introduced individually. Virus propagation in mouse brains was substantially enhanced if both L mutations were present simultaneously, but infection remained mostly nonsymptomatic. Only if all three amino acid substitutions were combined did BDV replicate vigorously and induce early disease in mice. Interestingly, the virulence-enhancing effect of the R66K mutation in P could be attributed to reduced negative regulation of polymerase activity by the viral X protein. Our data demonstrate that BDV replication competence in mice is mediated by the polymerase complex rather than the viral envelope and suggest that altered regulation of viral gene expression can favor adaptation to new host species.
Kaposi's Sarcoma-Associated Herpesvirus Latency-Associated Nuclear Antigen 1 Mimics Epstein-Barr Virus EBNA1 Immune Evasion through Central Repeat Domain Effects on Protein Processing
Authors: Kwun Hyun Jin , da Silva Suzane Ramos , Shah Ishita M. , Blake Neil , Moore Patrick S. , Chang Yuan
Published: May 2007

Kaposi's sarcoma-associated herpesvirus (KSHV/human herpesvirus 8 [HHV8]) and Epstein-Barr virus (EBV/HHV4) are distantly related gammaherpesviruses causing tumors in humans. KSHV latency-associated nuclear antigen 1 (LANA1) is functionally similar to the EBV nuclear antigen-1 (EBNA1) protein expressed during viral latency, although they have no amino acid similarities. EBNA1 escapes cytotoxic lymphocyte (CTL) antigen processing by inhibiting its own proteosomal degradation and retarding its own synthesis to reduce defective ribosomal product processing. We show here that the LANA1 QED-rich central repeat (CR) region, particularly the CR2CR3 subdomain, also retards LANA1 synthesis and markedly enhances LANA1 stability in vitro and in vivo. LANA1 isoforms have half-lives greater than 24 h, and fusion of the LANA1 CR2CR3 domain to a destabilized heterologous protein markedly decreases protein turnover. Unlike EBNA1, the LANA1 CR2CR3 subdomain retards translation regardless of whether it is fused to the 5′ or 3′ end of a heterologous gene construct. Manipulation of sequence order, orientation, and composition of the CR2 and CR3 subdomains suggests that specific peptide sequences rather than RNA structures are responsible for synthesis retardation. Although mechanistic differences exist between LANA1 and EBNA1, the primary structures of both proteins have evolved to minimize provoking CTL immune responses. Simple strategies to eliminate these viral inhibitory regions may markedly improve vaccine effectiveness by maximizing CTL responses.
Rates of Reactivation of Latent Herpes Simplex Virus from Mouse Trigeminal Ganglia Ex Vivo Correlate Directly with Viral Load and Inversely with Number of Infiltrating CD8+T Cells
Authors: Hoshino Yo , Pesnicak Lesley , Cohen Jeffrey I. , Straus Stephen E.
Published: May 2007

Herpes simplex viruses (HSV) reactivate at rates proportional to the viral loads in latently infected ganglia. However, these rates vary substantially among infected animals. We assessed whether the numbers of HSV-specific CD8+T cells infiltrating latently infected ganglia also affect reactivation rates and contribute to their variability. Following corneal infection of mice with HSV type 2 (HSV-2), we quantified the latent viral loads in dissociated trigeminal ganglia by real-time PCR, the numbers of infiltrating CD8+T cells by flow cytometry, and the rates of reactivation by the detection of cell-free virus released from ganglion cells cultured in 96-well plates. The reactivation rates correlated directly with the latent viral loads (P= 0.001) but did so more strongly (P= 10−7) when cultures were depleted of CD8+T cells. Reactivation rates were reduced in a dose-dependent fashion by adding back ganglion CD8+T cells to the cultures (P= 0.003). We related the latent viral loads, numbers of CD8+T cells, and reactivation rates by mathematical equations. The rates of reactivation predicted from latent viral loads and numbers of infiltrating CD8+T cells in dissociated ganglia correlated with the observed rates of reactivation (P= 0.04). The reactivation of HSV-2 from ganglia ex vivo is determined both by the latent viral load and the number of infiltrating CD8+T cells.
The N Terminus of the Herpes Simplex Virus Type 1 Triplex Protein, VP19C, Cannot Be Detected on the Surface of the Capsid Shell by Using an Antibody (Hemagglutinin) Epitope Tag
Authors: Solé Marieta , Perkins Edward M. , Frisancho Augusto , Huang Eugene , Desai Prashant
Published: May 2007

The herpes simplex virus (HSV) triplex is a complex of three protein subunits, VP19C and a dimer of VP23 that is essential for capsid assembly. We have derived HSV-1 recombinant viruses that contain monomeric red fluorescent protein (mRFP1), a Flu hemagglutinin (HA) epitope, and a six-histidine tag fused to the amino terminus of VP19C. These viruses were capable of growth on Vero cells, indicating that the amino terminus of VP19C could tolerate these fusions. By use of immunoelectron microscopy methods, capsids that express VP19C-mRFP but not VP19C-HA were labeled with gold particles when incubated with the corresponding antibody. Our conclusion from the data is that a large tag at the N terminus of VP19C was sufficiently exposed on the capsid surface for polyclonal antibody reactivity, while the small HA epitope was inaccessible to the antibody. These data indicate that an epitope tag at the amino terminus of VP19C is not exposed at the capsid surface for reactivity to its antibody.
Human Immunodeficiency Virus Type 1 Assembly, Budding, and Cell-Cell Spread in T Cells Take Place in Tetraspanin-Enriched Plasma Membrane Domains
Authors: Jolly Clare , Sattentau Quentin J.
Published: May 2007

Human immunodeficiency virus type-1 (HIV-1) egress from infected CD4
+
T cells is thought to be via assembly and budding at the plasma membrane and may involve components of the T-cell secretory apparatus, including tetraspanins. However, many studies on HIV-1 assembly have examined the trafficking of viral proteins in isolation, and most have used immortalized epithelial, fibroblastic, or hematopoietic cell lines that may not necessarily reflect natural infection of susceptible T cells. Here we have used immunofluorescence and cryoimmunoelectron microscopy (CEM) to examine protein transport during HIV-1 assembly in productively infected Jurkat CD4
+
T cells and primary CD4
+
T cells. The HIV-1 envelope glycoprotein (Env) and the core protein (Gag) colocalize strongly with CD63 and CD81 and less strongly with CD9, whereas no colocalization was seen between Env or Gag and the late endosome/lysosomal marker Lamp2. CEM revealed incorporation of CD63 and CD81 but not Lamp2 into virions budding at the plasma membrane, and this was supported by immunoprecipitation studies, confirming that HIV-1 egress in T cells is trafficked via tetraspanin-enriched membrane domains (TEMs) that are distinct from lysosomal compartments. CD63, CD81, and, to a lesser extent, CD9 were recruited to the virological synapse (VS), and antibodies against these tetraspanins reduced VS formation. We propose that HIV-1 promotes virus assembly and cell-cell transfer in T cells by targeting plasma membrane TEMs.
Vif Counteracts a Cyclophilin A-Imposed Inhibition of Simian Immunodeficiency Viruses in Human Cells
Authors: Takeuchi Hiroaki , Buckler-White Alicia , Goila-Gaur Ritu , Miyagi Eri , Khan Mohammad A. , Opi Sandrine , Kao Sandra , Sokolskaja Elena , Pertel Thomas , Luban Jeremy , Strebel Klaus
Published: May 2007

Vif is a primate lentiviral accessory protein that is crucial for viral infectivity. Vif counteracts the antiviral activity of host deaminases such as APOBEC3G and APOBEC3F. We now report a novel function of African green monkey simian immunodeficiency virus (SIVagm) Vif that promotes replication of SIVagm in human cells lacking detectable deaminase activity. We found that cyclophilin A (CypA) was excluded from wild-type SIV particles but was efficiently packaged into
vif
-deficient SIVagm virions. The presence of CypA in
vif
-defective SIVagm was correlated with reduced viral replication. Infection of CypA knockout Jurkat cells or treatment of Jurkat cells with cyclosporine A eliminated the Vif-sensitive inhibition and resulted in replication profiles that were similar for wild-type and
vif
-deficient SIVagm. Importantly, the inhibitory effect of CypA was restricted to virus-producing cells and was TRIM5α independent. The abilities of SIVagm Vif to inhibit encapsidation of CypA and to increase viral infectivity were shared by rhesus macaque SIV Vif and thus seem to be general properties of SIV Vif proteins. Exclusion of CypA from SIVagm particles was not associated with intracellular degradation, suggesting a mode of Vif action distinct from that proposed for APOBEC3G. This is the first report of a novel
vif
-sensitive antiviral activity of human CypA that may limit zoonotic transmission of SIV and the first demonstration of CypA encapsidation into a virus other than human immunodeficiency virus type 1.
Natural Variation in the V3 Crown of Human Immunodeficiency Virus Type 1 Affects Replicative Fitness and Entry Inhibitor Sensitivity
Authors: Lobritz Michael A. , Marozsan Andre J. , Troyer Ryan M. , Arts Eric J.
Published: May 2007

Natural polymorphisms in the heterogeneous human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein may have an impact on both sensitivity to entry inhibitors and viral replicative fitness. Of significant interest is variation in the V3 crown due to its involvement in direct engagement with the coreceptor. Two positions in the crown (318 and 319) appear to be important in determining intrinsic susceptibility to multiple entry inhibitors. Thus, we evaluated a series of natural polymorphisms at positions 318 and 319 in three distinct CCR5-tropic envelope genetic backgrounds to address their role in replicative fitness and sensitivity to entry inhibitors. Change at position 319 to each of the three major consensus amino acids (A, T, and R) resulted in variation in sensitivity to entry inhibitors and altered replicative fitness, but the effects of any one amino acid depended on the envelope context. Change of the nearly invariant tyrosine at position 318 to a rare arginine resulted in increased sensitivity to entry inhibitors and decreased replicative fitness independent of envelope context. Polymorphisms in the V3 crown that showed increased susceptibility to entry inhibitors also exhibited decreased entry efficiency, replicative fitness in primary peripheral blood mononuclear cells, and ability to replicate in primary macrophages. These findings suggest that differences in coreceptor affinity and/or avidity may underlie these phenotypic characteristics.
Susceptibility of Recently Transmitted Subtype B Human Immunodeficiency Virus Type 1 Variants to Broadly Neutralizing Antibodies
Authors: Quakkelaar Esther D. , van Alphen Floris P. J. , Boeser-Nunnink Brigitte D. M. , van Nuenen Ad C. , Pantophlet Ralph , Schuitemaker Hanneke
Published: May 2007

The ability of the broadly neutralizing human immunodeficiency virus type 1 (HIV-1) specific human monoclonal antibodies (MAbs) b12, 2G12, 2F5, and 4E10 to neutralize recently transmitted viruses has not yet been explored in detail. We investigated the neutralization sensitivity of subtype B HIV-1 variants obtained from four primary HIV infection cases and six transmission couples (four homosexual and two parenteral) to these MAbs. Sexually transmitted HIV-1 variants isolated within the first 2 months after seroconversion were generally sensitive to 2F5, moderately resistant to 4E10 and b12, and initially resistant but later more sensitive to 2G12 neutralization. In the four homosexual transmission couples, MAb neutralization sensitivity of HIV in recipients did not correlate with the MAb neutralization sensitivity of HIV from their source partners, whereas the neutralization sensitivity of donor and recipient viruses involved in parenteral transmission was more similar. For a fraction (11%) of the HIV-1 variants analyzed here, neutralization by 2G12 could not be predicted by the presence of N-linked glycosylation sites previously described to be involved in 2G12 binding. Resistance to 2F5 and 4E10 neutralization did also not correlate with mutations in the respective core epitopes. Overall, we observed that the neutralization resistance of recently transmitted subtype B HIV-1 variants was relatively high. Although 8 of 10 patients had viruses that were sensitive to neutralization by at least one of the four broadly neutralizing antibodies studied, 4 of 10 patients harbored at least one virus variant that seemed resistant to all four antibodies. Our results suggest that vaccine antigens that only elicit antibodies equivalent to b12, 2G12, 2F5, and 4E10 may not be sufficient to protect against all contemporary HIV-1 variants and that additional cross-neutralizing specificities need to be sought.
Effects of training to implement new working methods to reduce knee strain in floor layers. A two-year follow-up
Authors: Jensen L K , Friche C
Published: May 2007

Objectives:

Follow-up study after two years to measure the effects of an implementation strategy consisting of information, education and training in the use of new tools and working-methods for the purpose of reducing knee strain and knee complaints in floor layers.

Methods:

Training of floor layers (n = 292) in using new working methods was evaluated by questionnaires during the courses. Two years later, this follow-up included questionnaires for the course participants (n = 216) and a control group of floor layers (not trained on courses) (n = 454).

Results:

Two years after training, 38% used the new working methods weekly or daily compared to 37% three months after the courses, and 10% before. Among controls, only 16% had used the new working methods weekly or daily. The risk of knee complaints >30 days (OR 2.46, 95% CI 1.03 to 5.83) or locking of the knees (OR 2.89, 95% CI 1.11 to 7.5) was more than double among floor layers who had used the new working-methods for less than one year compared to those who had used them more. The results were adjusted for age, body mass index, and stress. The reduction in more severe knee complaints was greatest if floor layers started to use the new working methods before they developed knee problems. Other musculoskeletal complaints did not increase.

Conclusion:

This indicates that, within a two-year perspective, the implementation strategy to introduce new working methods in the floor laying trade has been effective; the number of floor layers using the new working-methods has increased, and severe knee problems have reduced.
Prognostic factors for work ability in sicklisted employees with chronic diseases
Authors: Slebus Frans G , Kuijer P Paul F M , Willems J (Han) H B M , Sluiter Judith K , Frings-Dresen Monique H W
Published: May 2007

Objective:

Identifying prognostic factors for work ability in sicklisted employees with myocardial infarction (MI), chronic low back pain (cLBP) and major depressive disorder (MDD) in order to establish an objective basis for work ability evaluation.

Design:

Systematic literature search in PubMed database (1 January 1990 to 1 July 2006) with the Yale prognostic research filter. Inclusion criteria were as follows: (1) work-disabled employees; (2) MI, cLBP or MDD patients; (3) longitudinal designs; and (4) return to work or compensation status as outcome measure.

Results:

Four studies on MI met the inclusion criteria and described the following prognostic factors for work ability in the acute phase of the disease and disablement: lower age; male gender; no financial basis on which to retire; lower physical job demands; fewer somatic complaints; no anxiety attacks; no diabetes; no heart failure; no atrial fibrillation; no Q waves; and a short time interval between MI and presentation at the occupational medicine clinic. Two studies on cLBP met the inclusion criteria and described the following prognostic factors for work ability after 3 months’ work disablement: lower age; male gender; no treatment before sick listing; surgery in the first year of sick listing; being a breadwinner; less pain; better general health; higher job satisfaction; lower physical and/or psychological demands at work; and a higher decision latitude at work. No relevant MDD studies were found.

Conclusion:

In the earlier phases of work disablement in MI and cLBP patients, only a few studies describe disease-specific, environmental and personal prognostic factors for return to work. No studies describe prognostic factors for MDD. More evidence is needed on the topic of prognostic factors for return to work in employees with chronic diseases.
Carbon Nanotube Based Microwave Resonator Gas Sensors
Authors: McGRATH M. P. , PHAM A.
Published: May 2007

This paper reviews our work on the development of microwave carbon nanotube resonator sensors for gas detection. The sensor consists of a radio frequency resonator coated with a layer of carbon nanotubes. Upon exposure to gasses, the resonant frequency of the sensor shifts to indicate the presence of gasses. Our experimental results demonstrate that the microwave carbon nanotube resonator sensor achieves a sensitivity of 4000 Hz/ppm upon exposure to ammonia and the resonant frequency is recovered when ammonia is evacuated. The sensing mechanism is dependent on electron transfer from the ammonia to the nanotubes. This sensor platform has great potential for wireless sensing network applications.
PARTICLE DISTRIBUTION AND NUCLEAR STOPPING IN Au+Au COLLISIONS AT $\sqrt{s_{NN}}=200~{\rm GeV}$
Authors: ZHU L. L. , YANG C. B.
Published: May 2007

The transverse momentum distribution of charged particles is investigated for gold–gold collisions at [Formula: see text]. A simple parametrization is suggested for the particle distribution based on the nuclear stopping effect. The model can fit very well in both the transverse momentum distributions at different pseudo-rapidities and the pseudo-rapidity distributions at different centralities. The ratio of rapidity distributions for peripheral and central collisions is calculated and compared with the data.
STOCHASTIC BACKGROUND OF GRAVITATIONAL WAVES "TUNED" BY f(R) GRAVITY
Authors: CAPOZZIELLO SALVATORE , CORDA CHRISTIAN , DE LAURENTIS MARIAFELICIA
Published: May 2007

We show that the stochastic background of gravitational waves, produced in the early cosmological epochs, depends strictly on the assumed theory of gravity. In particular, the specific form of the function f(R), where R is the Ricci scalar, is related to the evolution and the production mechanism of gravitational waves. On the other hand, detecting the stochastic background by the forthcoming interferometric experiments (VIRGO, LIGO, LISA) could be a further tool to select the effective theory of gravity.
CONSTRUCTION OF LAGRANGIAN LOCAL SYMMETRIES FOR GENERAL QUADRATIC THEORY
Authors: DERIGLAZOV A. A.
Published: May 2007

We propose a procedure which allows one to construct local symmetry generators of general quadratic Lagrangian theory. Manifest recurrence relations for generators in terms of the so-called structure matrices of the Dirac formalism are obtained. The procedure fulfill in terms of initial variables of the theory, and does not imply either separation of constraints on first and second class subsets or any other choice of basis for constraints.
SMALL SIZE PENTAQUARK WIDTH: CALCULATION IN QCD SUM RULES
Authors: OGANESIAN A. G.
Published: May 2007

The pentaquark width is calculated in QCD sum rules. The higher dimension operators contribution is accounted. It is shown, that ΓΘ should be very small, less than 1 MeV.
NEW APPROACH TO N-BODY RELATIVISTIC QUANTUM MECHANICS
Authors: GU YING-QIU
Published: May 2007

In this paper, we propose a new approach to the relativistic quantum mechanics for many-body, which is a self-consistent system constructed by juxtaposed but mutually coupled nonlinear Dirac's equations. The classical approximation of this approach provides the exact Newtonian dynamics for many-body, and the nonrelativistic approximation gives the complete Schrödinger equation for many-body.
ASYMPTOTIC QUASINORMAL MODES OF A NONCOMMUTATIVE GEOMETRY INSPIRED SCHWARZSCHILD BLACK HOLE
Authors: GIRI PULAK RANJAN
Published: May 2007

We study the asymptotic quasinormal modes for the scalar perturbation of the noncommutative geometry inspired Schwarzschild black hole in 3+1 dimensions. We have considered M ≥ M0, which effectively correspond to a single horizon Schwarzschild black hole with correction due to noncommutativity. We have shown that for this situation the real part of the asymptotic quasinormal frequency is proportional to ln (3). The effect of noncommutativity of space–time on quasinormal frequency arises through the constant of proportionality, which is Hawking temperature TH(θ). We also consider the two-horizons case and show that in this case also the real part of the asymptotic quasinormal frequency is proportional to ln (3).
TRANSVERSE WARD–TAKAHASHI RELATION FOR THE FERMION–BOSON VERTEX FUNCTION IN FOUR-DIMENSIONAL ABELIAN GAUGE THEORY
Authors: HE HAN-XIN
Published: May 2007

In this paper, we give a general formula of the transverse Ward–Takahashi relation for the fermion–boson vertex function in momentum space in four-dimensional Abelian gauge theory, with the complete expression of the integral-term involving the nonlocal axial-vector vertex function, from which the corresponding one-loop expression is derived straightforwardly. Then we deduce carefully this transverse Ward–Takahashi relation to one-loop order in d dimensions, with d = 4 + ∊. The result shows that this relation holds in d dimensions if the combination ελμνργργ5 in d dimensions is replaced with -½{γλ, σμν} by the identity of γ-matrices, and there is no additional piece proportional to (d-4) to include for this relation to hold in four dimensions. This result is further confirmed by an explicit computation of terms in this transverse WT relation to one-loop order. We also discuss the momentum space representation of the nonlocal term in the transverse WT relation.
UNIQUENESS OF PETROV TYPE D SPATIALLY INHOMOGENEOUS IRROTATIONAL SILENT MODELS
Authors: APOSTOLOPOULOS PANTELIS S. , CAROT JAUME
Published: May 2007

The consistency of the constraint with the evolution equations for spatially inhomogeneous and irrotational silent (SIIS) models of Petrov type I, demands that the former are preserved along the timelike congruence represented by the velocity of the dust fluid, leading to new nontrivial constraints. This fact has been used to conjecture that the resulting models correspond to the spatially homogeneous (SH) models of Bianchi type I, at least for the case where the cosmological constant vanish. By exploiting the full set of the constraint equations as expressed in the 1+3 covariant formalism and using elements from the theory of the spacelike congruences, we provide a direct and simple proof of this conjecture for vacuum and dust fluid models, which shows that the Szekeres family of solutions represents the most general class of SIIS models. The suggested procedure also shows that, the uniqueness of the SIIS of the Petrov type D is not, in general, affected by the presence of a nonzero pressure fluid. Therefore, in order to allow a broader class of Petrov type I solutions apart from the SH models of Bianchi type I, one should consider more general "silent" configurations by relaxing the vanishing of the vorticity and the magnetic part of the Weyl tensor but maintaining their "silence" properties, i.e. the vanishing of the curls of Eab, Hab and the pressure p.
HADRONIC B DECAYS: A GENERAL APPROACH
Authors: IMBEAULT MAXIME , DATTA ALAKABHA , LONDON DAVID
Published: May 2007

In this paper, we propose a general approach for describing hadronic B decays. Using this method, all amplitudes for such decays can be expressed in terms of contractions, though the matrix elements are not evaluated. Many years ago, Buras and Silvestrini proposed a similar approach. However, our technique goes beyond theirs in several ways. First, we include recent theoretical and experimental developments which indicate which contractions are negligible, and which are expected to be smaller than others. Second, we show that all B-decay diagrams can be simply expressed in terms of contractions. This constitutes a formal proof that the diagrammatic method is rigorous. Third, we show that one reproduces the relations between tree and electroweak-penguin diagrams described by Neubert and Rosner, and by Gronau, Pirjol and Yan. Fourth, although the previous results hold to all orders in αs, we show that it is also possible to work order-by-order in this approach. In this way it is possible to make a connection with the matrix-element evaluation methods of QCD factorization (QCDfac) and perturbative QCD (pQCD). Finally, using the contractions approach, we reevaluate the question of whether there is a "B → πK puzzle." At [Formula: see text], we find that the diagram ratio |C′/T′| is about 0.17, a factor of 10 too small to explain all the B → πK data. Both QCDfac and pQCD find that, at [Formula: see text], the value of |C′/T′| may be raised to only about 2–3 times its lowest-order value. We therefore conclude that, assuming the effect is not a statistical fluctuation, it is likely that the value of |C′/T′| is similar to its [Formula: see text] result, and that there really is a B → πK puzzle.
THE NUCLEAR EQUATION OF STATE OBSERVED IN EARTHBOUND EXPERIMENTS
Authors: HARTNACK CH. , AICHELIN JÖRG , OESCHLER H.
Published: May 2007

The stiffness of the hadronic equation of state has been extracted from the production rate of K+ mesons in heavy ion collisions around 1 A GeV incident energy. The data are best described with a compression modulus K around 200 MeV, a value which is usually called "soft." This is concluded from a detailed comparison of the results of transport theories with the experimental data using two different procedures: (i) the energy dependence of the ratio of K+ from Au + Au and C + C collisions and (ii) the centrality dependence of the K+ multiplicities. It is demonstrated that input quantities of these transport theories which are not precisely known, like the kaon–nucleon potential, the ΔN → N K+ Λ cross-section or the lifetime of the Δ in matter do not modify this conclusion.
EFFECTS OF Δ-BARYON INTERACTION STRENGTH ON NEUTRON STARS PROPERTIES
Authors: DE OLIVEIRA J. C. T. , DUARTE S. B. , RODRIGUES H. , CHIAPPARINI M. , KYOTOKU M.
Published: May 2007

We investigate the effect of Δ-resonance interaction strength on the equation of state of asymmetric hadronic matter and neutron stars structure. We discuss Δ-matter formation at high densities in the context of a relativistic mean field theory. We show that the attractive nature of the Δ-baryon interaction can induce a phase transition accompanying Δ-matter formation, at values of densities presumably existing in central regions of neutron stars. The possibility of a rich Δ-resonance neutron star is presented using the proposed equation of state.
ON THE ROLE OF THE ADIABATIC INDEX IN THE STABILITY OF NEUTRON STARS
Authors: JACOBSEN RAFAEL B. , VASCONCELLOS CÉSAR A. Z. , BODMANN BARDO E. J. , HADJIMICHEF DIMITER
Published: May 2007

We study the influence of interaction strengths on nuclear properties and global static properties of neutron stars with emphasis on the adiabatic index, considering also the constraint of chemical equilibrium and charge neutrality. We develop an equation of state (EoS) in the framework of an extended effective QHD model using a parameterized phenomenological Lagrangian density containing the fundamental baryon octet, the σ, ω and ϱ meson fields and the lightest charged leptons. The results of our approach show that, for a small range of values of the baryon–meson coupling parameters, we can consistently describe nuclear matter and the structure of neutron stars. Our results indicate that in the energy density range above hyperon thresholds, the behavior of the adiabatic index is roughly comparable to the corresponding one in the case of an extreme relativistic hydrodynamical perfect fluid.
RELATIVISTIC SOMMERFELD LOW TEMPERATURE EXPANSION
Authors: LOURENÇO O. , DUTRA M. , DELFINO A. , SÁ MARTINS J. S.
Published: May 2007

We derive a relativistic Sommerfeld expansion for thermodynamic quantities in many-body fermionic systems. The expansion is used to generate the equation of state of the Walecka model and its isotherms. We find that these results are in good agreement with numerical calculations, even when the expansion is truncated at its lowest order, in the low temperature regime, defined by T/xf ≪ 1. Although the interesting region near the liquid-gas phase transition is excluded by this criterion, the expansion may still find usefulness in the study of very cold nuclear matter systems, such as neutron stars.
CHARGED RELATIVISTIC STARS AND THE ANISOTROPIC FORMALISM
Authors: NEGREIROS RODRIGO PICANÇO , MALHEIRO MANUEL
Published: May 2007

In this paper, we study the anisotropy of charged relativistic stars. We show that the structure of the star is changed by the electric field and this electric field destroys the isotropy of the star making the radial component of the energy–momentum tensor different from the angular ones. Charged compact stars have already been studied by Bekenstein [Phys. Rev. D4 (1971) 2185] and anisotropic stars were reviewed recently [Gen. Relativ. Gravit.34 (2002) 1793]. We present the solutions obtained in [Phys. Rev. D68 (2003) 084004] and re-solve the problem using the anisotropic formalism. We find that the results are different and this difference occurs due to the fact that the boundary condition of the anisotropic formalism is not correct, leading to an inconsistent physical situation.
A FINITE TEMPERATURE RELATIVISTIC NUCLEAR MODEL FOR NEUTRON STARS IN A SLOW ROTATIONAL SCENARIO
Authors: MESQUITA ALEXANDRE , RAZEIRA MOISES , VASCONCELLOS CÉSAR A. Z. , BODMANN BARDO E. J.
Published: May 2007

We study the effects of temperature in hadron dense matter within a generalized relativistic mean field approach based on the naturalness of the coupling constants of the theory. The Lagrangian density of our formulation contains nonlinear self-couplings of the σ meson field coupled to baryons and to the ω and ϱ meson fields. Moreover, we use the Sommerfeld and Hartle approximations to extend our approach to the finite temperature domain and slow rotational scenario. Both Sommerfeld and Hartle approximation allows a drastic simplification of computational work while improving the capability of theoretical analysis of the role of temperature and rotation on properties of protoneutron stars. Our predictions indicate that in the slow rotating regimen, neutron stars density profiles as well as the maximum mass and the inertial moment of these stellar objects are well approximated by the zero temperature approximation.
STRANGE MATTER AND STRANGE STARS WITH TSALLIS STATISTICS
Authors: RAZEIRA MOISÉS , BODMANN BARDO E. J. , VASCONCELLOS CÉSAR A. ZEN
Published: May 2007

We investigate the properties of β-equilibrated electrically charged neutral strange matter and strange stars at finite temperature in the framework of Tsallis statistics [C. Tsallis, J. Stat. Phys.52 (1988) 479]. As the main result of our study we find out that a QHD description of nuclear matter combined with Tsallis statistics may open new possibilities for nuclear matter models.
SIGNATURES OF ISOVECTOR COMPONENTS OF A LIGHT SCALAR MESON IN PULSARS
Authors: LÜTZ EDUARDO , RAZEIRA MOISÉS , BODMANN BARDO E. J. , VASCONCELLOS CÉSAR A. ZEN
Published: May 2007

In a previous work, we have predicted an isovector component of the light scalar meson sector by using the chiral symmetry transformation formalism. On the basis of this result, we study dense hadronic matter in a generalized relativistic mean field approach with σ, ω and ρ mesons as well as nonlinear self-couplings of the I = 1 component of a light scalar meson field and compare its predictions for neutron star properties and with results from different models for nuclear matter found in the literature.
LITHIUM IN THE STELLAR OPEN CLUSTER M67
Authors: CANTO MARTINS B. L. , DO NASCIMENTO J. D. , DE MEDEIROS J. R. , LÈBRE A. , RICHARD O. , DE LAVERNY P. , MELO C.
Published: May 2007

In this work we present atmospheric parameters and Li abundances, obtained from a detailed spectroscopic analysis, for a large sample of stars with different evolutionary stages (turn-off, subgiant and giant stars) in the open cluster M67. The observations were carried out with high resolution (R ~ 47,000) and high S/N using the UVES+FLAMES at VLT/UT2. From available photometry and computed synthetic spectra for the region around the lithium line at 6707.75 Å, we derive atmospheric parameters (T eff , log g, [ Fe/H ], v sin i) and Li abundances for each star, in order to better understand the level of mixing and convective dilution of evolved stars in M67.