bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatio‐temporal variation in mortality rates of Mecodema spp. (Coleoptera: Carabidae) across a forest‐grassland edge in New Zealand
Authors: EWERS ROBERT M.
Published: January 2008

Abstract. 

Edge effects are a highly cited issue in conservation biology with a wealth of empirically described impacts on invertebrates, but the mechanisms underlying the responses of individual species to habitat edges have been seldom tested. One often‐raised hypothesis is that individual species vary in their ability to survive along a gradient of changing microclimatic conditions across habitat edges.

I used a phylogenetically controlled, translocation experiment to investigate edge‐driven variation in adult mortality rate for two closely related species that have contrasting abundance patterns with respect to forest‐grassland edges; the habitat generalist Mecodema fulgidum Broun (Coleoptera: Carabidae) and the forest‐dwelling Mecodema rugiceps Sharp.

Adult individuals of both species were live‐caught and translocated into containers at varying distances along an edge gradient extending from 1024 m inside a large forest fragment and 64 m into the surrounding grassland matrix. Experimental containers were connected to the above‐ and below‐ground environments via mesh‐covered panels, and beetle mortality over a 4‐month period in the 2006/2007 austral summer was recorded.

Overall, mortality was higher for the habitat specialist M. rugiceps than for the generalist M. fulgidum. Neither species exhibited an edge‐related trend in mortality, nor were mortality rates correlated with microclimatic gradients across the edge.

Weather records for the summer indicated that M. rugiceps was more sensitive than M. fulgidum to a soil moisture deficit that became more pronounced as summer progressed. Analysis of a 10‐year climate record shows that soil moisture deficits occur annually, suggesting that seasonal variation in soil moisture may contribute to the variation in the distribution and abundance of the two species.
Oral Health Program Preferences among Pregnant Women in a Managed Care Organization
Authors: Thoele Merry J. , Asche Stephen E. , Rindal D. Brad , Fortman Kristine K.
Published: January 2008

Objective: The purpose of the study was to understand the oral health information preferences of pregnant women and new mothers. Methods: This study was conducted at a Minnesota managed care organization. A random sample of 250 women with public program insurance and 250 privately insured women was selected from the population of pregnant women in the claims systems. The study consisted of a mailed survey and phone contact to nonresponders. The analytic sample consisted of 123 public‐pay and 127 private‐pay respondents. Descriptive statistics summarize the preferences for oral health care topics. Results: Receiving information by mail was preferred by both groups. Women favored information concerning infant‐specific oral health more than information on both mother and infant oral health. While public‐pay respondents had more enthusiasm for many topics, the topic preference rankings within each sample were similar. Conclusion: Similarities in program preferences suggest that common interventions could be designed that would appeal to both groups without extensive tailoring.
Identification and Description of Mobile Dental Programs – A Brief Communication
Authors: Carr Brian R. , Isong Umo , Weintraub Jane A.
Published: January 2008

Objectives: The purpose of this study was to identify and describe mobile dental programs in California. Methods: The programs were identified by Internet searches, county health officers, local dental society directors, mobile program directors, and others. A cross‐sectional survey was mailed to program directors if their programs provide clinical dental services beyond screening and education. Results: In California, 33 programs were identified; survey response rate was 70 percent. The populations most likely to be served were those with low‐income (100 percent), elementary (77 percent) and preschool (68 percent) children, non‐English speakers (64 percent), and the Medicaid‐eligible (64 percent). At least half of the programs were providing services in designated Dental Health Professional Shortage Areas. Most program directors indicated that if their program was discontinued, it would be “very difficult” (61 percent) or “difficult” (35 percent) for the target populations to get dental services. Conclusions: Mobile dental programs are a highly variable, but important, strategy for bringing dental care to many underserved populations.
Racial and Ethnic Disparity in Oral Cancer Awareness and Examination: 2003 New York State BRFSS
Authors: Oh Junhie , Kumar Jayanth , Cruz Gustavo
Published: January 2008

Objectives: This study documents the level of oral cancer awareness and examination among New York State adults and evaluates the determinants of disparities in oral cancer detection. Methods: The 2003 New York State Behavioral Risk Factor Surveillance System gathered information on current awareness of oral cancer and receipt of oral cancer examination from 5,544 adults. To assess whether the racial/ethnic factor remains important for the awareness, receipt, and source of oral cancer examination after controlling for other socioeconomic and health care access variables, bivariate and multiple logistic regression analyses were conducted using SAS and SUDAAN. Results: Even though a majority of State adults (80.4 percent) had heard about oral cancer, about three‐quarters of these adults (74.3 percent) had never heard about an oral cancer test or examination. Only 35 percent of the adults reportedly received an oral cancer examination in their lifetime. Adults with Hispanic origin were less likely to have heard about and received an oral cancer examination. Regarding the source of the examination, some 72 percent of the examinations were conducted by a dental professional; the remaining 28 percent were performed by a physician, nurse, or nurse practitioner. Non‐Hispanic Blacks were more likely to have received an oral cancer examination from health care providers other than a dentist or dental hygienist. Conclusions: These data suggest the need to improve the oral cancer awareness and examination rate in New York State. Routine examination of the mouth by primary care providers as part of a physical examination would provide the best opportunity for improving the low oral cancer examination rates in minority populations.
Rural Latino Immigrant Caregivers' Conceptions of Their Children's Oral Disease
Authors: Horton Sarah , Barker Judith C.
Published: January 2008

Objective: The aim of this study was to examine Latino immigrant caregivers' explanatory models of the causes of early childhood caries (ECC). Methods: In a rural area, we conducted 71 open‐ended qualitative interviews with 26 Mexican immigrant and 12 Salvadoran immigrant caregivers of children under 6 about the causes of ECC. Two researchers independently read each interview and classified each interviewee's response. Results: Caregivers mentioned three biomedical causes of oral disease (sweets, poor oral hygiene, and bottle‐feeding) and two lay or popular causes (lack of milk consumption and “bad” genes). Although caregivers were aware that the consumption of sweet foods causes decay, they expressed particular confusion about how bottle‐feeding causes decay. Nineteen caregivers attributed decay specifically to bottle‐feeding, yet 14 believed the cause of decay was the bottle's nipple. Seven Mexican immigrant caregivers attributed their children's decay specifically to a lack of calcium, and six immigrant caregivers to “bad teeth genes.”Conclusions: Conceptions of oral disease derived from the caregivers' own dental experiences, their conceptions of the body, and interactions with dental professionals. The fact that biomedical explanations dominate the list of causes of caries for both groups indicates that the caregivers' explanatory models of oral disease are powerfully shaped by interactions with health professionals. Immigrant caregivers' mistaking of the baby bottle's nipple as the source of decay indicates the need for more effective oral health promotion. Yet the Mexican immigrants' conceptions of a lack of calcium as a major factor in their children's decay may illustrate a strong cultural link between teeth and milk.
Dental Treatment Improves Self‐Rated Oral Health in Homeless Veterans – A Brief Communication
Authors: Gibson Gretchen , Reifenstahl Erik F. , Wehler Carolyn J. , Rich Sharron E. , Kressin Nancy R. , King Tracy B. , Jones Judith A.
Published: January 2008

Objective: The aim of this study was to assess homeless veterans' perception of their oral health and the impact that oral disease and treatment have on self‐assessed quality of life. Methods: Outcomes included measures of general and oral‐specific quality of life and functional status. Single‐item self‐report of oral health and the General Oral Health Assessment Index were assessed at baseline and after treatment. Results: One hundred and twelve veterans completed the baseline questionnaire, and 48 completed the follow‐up. Veterans who were eligible for ongoing dental care had improved General Oral Health Assessment scores, while patients who received only emergency dental care saw a decreased score (2.46 versus −2.12). General Oral Health Assessment improvement was significantly related to fewer teeth at baseline (18 versus 23), a lower baseline General Oral Health Assessment (23.6 versus 28.1), having a denture visit (22 versus 35 percent), and improvement in self‐reported oral health (25 versus 42 percent). Conclusion: There was significant improvement in homeless veterans' perceived oral health after receiving dental care.
The Urban Transformation of the Developing World
Authors: Montgomery Mark R.
Published: February 2008

Sometime in the next 20 to 30 years, developing countries in Asia and Africa are likely to cross a historic threshold, joining Latin America in having a majority of urban residents. The urban demographic transformation is described here, with an emphasis on estimates and forecasts of urban population aggregates. To provide policy-makers with useful scientific guidance in the upcoming urban era, demographic researchers will need to refine their data sets to include spatial factors as well as urban vital rates and to make improvements to forecasting methods currently in use.
Urbanization and the Wealth of Nations
Authors: Bloom David E. , Canning David , Fink Günther
Published: February 2008

The proportion of a country's population living in urban areas is highly correlated with its level of income. Urban areas offer economies of scale and richer market structures, and there is strong evidence that workers in urban areas are individually more productive, and earn more, than rural workers. However, rapid urbanization is also associated with crowding, environmental degradation, and other impediments to productivity. Overall, we find no evidence that the level of urbanization affects the rate of economic growth. Our findings weaken the rationale for either encouraging or discouraging urbanization as part of a strategy for economic growth.
Genotyping of Human Papillomaviruses by a Novel One-Step Typing Method with Multiplex PCR and Clinical Applications
Authors: Nishiwaki Morie , Yamamoto Tomohiro , Tone Somako , Murai Taichi , Ohkawara Tatsuya , Matsunami Takakuni , Koizumi Motoiki , Takagi Yoshitake , Yamaguchi Jun , Kondo Nobuo , Nishihira Jun , Horikawa Takeharu , Yoshiki Takashi
Published: January 2008

We describe here a rapid, high-throughput genotyping procedure that allows the simultaneous detection of 16 high- and low-risk genital human papillomavirus (HPV) types by multiplex PCR in a single reaction tube. Multiplex PCR is based on the amplification of HPV DNA by sets of HPV genotype-specific primers, and the genotypes of HPV are visually identified by the sizes of amplicons after they are separated by capillary electrophoresis. The procedure does not include a hybridization step with HPV-specific probes and is rapid and labor-saving. We detected all 16 HPV genotypes (types 16, 58, 52, 51, 56, 31, 18, 39, 66, 59, 6, 33, 30, 35, 45, and 11) with a high sensitivity and a high degree of reproducibility. By using this newly developed method, we conducted a pilot study to examine the correlation between the prevalence and genotype distributions of HPV and the cytological group classifications for 547 cervical samples. Compared with the group of samples considered normal (14.7%), there was a significant increase in the prevalence of HPV in women with atypical squamous cells of unknown significance (61.3%), low-grade intraepithelial lesions (75.8%), and high-grade intraepithelial lesions (HSILs) (82.2%). The prevalence and distribution of type 58 were correlated with cytological malignancies, with the highest prevalence in women with HSILs. In conclusion, the novel multiplex PCR method described appears to be highly suitable not only for the screening of cervical cancer precursor lesions but also for the characterization of genotype distributions in large-scale epidemiological studies and HPV vaccination trials.
Application of Sensitive and Specific Molecular Methods To Uncover Global Dissemination of the Major RD
Rio
Sublineage of the Latin American-Mediterranean
Mycobacterium tuberculosis
Spoligotype Family
Authors: Gibson Andrea L. , Huard Richard C. , Gey van Pittius Nicolaas C. , Lazzarini Luiz Claudio Oliveira , Driscoll Jeffrey , Kurepina Natalia , Zozio Thierry , Sola Christophe , Spindola Silvana Miranda , Kritski Afrânio L. , Fitzgerald Daniel , Kremer Kristin , Mardassi Helmi , Chitale Poonam , Brinkworth Jessica , Garcia de Viedma Dario , Gicquel Brigitte , Pape Jean W. , van Soolingen Dick , Kreiswirth Barry N. , Warren Robin M. , van Helden Paul D. , Rastogi Nalin , Suffys Philip N. , Lapa e Silva Jose , Ho John L.
Published: January 2008

The Latin American-Mediterranean (LAM) family of
Mycobacterium tuberculosis
is believed to be the cause of ∼15% of tuberculosis cases worldwide. Previously, we defined a prevalent sublineage of the LAM family in Brazil by a single characteristic genomic deletion designated RD
Rio
. Using the Brazilian strains, we pinpoint an Ag85C
103
single nucleotide polymorphism (SNP) (screened by restriction fragment length polymorphism [RFLP] analysis) that correctly identified all LAM family strains. Importantly, all RD
Rio
strains concomitantly possessed the RD174 deletion. These genetic signatures, along with a newly developed multiplex PCR for rapid differentiation between “wild-type” and RD
Rio
strains, were then used to analyze an international collection of
M. tuberculosis
strains. RD
Rio
M. tuberculosis
was identified from four continents involving 11 countries. Phylogenetic analysis of the IS
6110
-RFLP patterns from representative RD
Rio
and LAM strains from Brazil, along with all representative clusters from a South African database, confirmed their genetic relatedness and transcontinental transmission. The Ag85C
103
SNP RFLP, as compared to results obtained using a PCR method targeting a LAM-restricted IS
6110
element, correctly identified 99.8% of LAM spoligotype strains. Together, these tests were more accurate than spoligotyping at categorizing strains with indefinable spoligotypes and segregated true LAM strains from those with convergent spoligotypes. The fact that RD
Rio
strains were identified worldwide highlights the importance of this LAM family sublineage and suggests that this strain is a global threat that should be specifically targeted by public health resources. Our provision of simple and robust molecular methods will assist the evaluation of the LAM family and the RD
Rio
sublineage.
Changes in Serotypes and Antimicrobial Susceptibility of Invasive
Streptococcus pneumoniae
Strains in Cleveland: a Quarter Century of Experience
Authors: Jacobs Michael R. , Good Caryn E. , Beall Bernard , Bajaksouzian Saralee , Windau Anne R. , Whitney Cynthia G.
Published: January 2008

The serotypes and susceptibilities to penicillin, macrolides, and clindamycin of 1,655 invasive isolates of
Streptococcus pneumoniae
recovered between 1979 and 2004 were determined. A precipitous decrease of 61% in the number of isolates was found following 2000, the year of 7-valent protein-conjugated pneumococcal vaccine (PCV7) introduction (139 versus 55 per 2-year period prior to versus after 2000;
P
< 0.001). This decrease was 84% in children <5 years old (80 versus 13 per 2-year period;
P
< 0.001) and 18 to 23% in other age groups (
P
, not significant). PCV7 serotypes decreased by 76% overall (103 versus 25 per 2-year period;
P
< 0.001) and by 92% in children <5 years old (65 versus 5 per 2-year period;
P
< 0.001), with significant decreases in six of the seven PCV serotypes. Other serotypes, except for type 19A, decreased from 32 to 22 per 2-year period, while type 19A increased from 4 to 8 per 2-year period, although none of these changes reached significance. Drug resistance emerged slowly, with the first penicillin-intermediate strain isolated in 1980 and the first macrolide/lincosamide-resistant strain isolated in 1984. The first penicillin-resistant strain was isolated in 1993. Resistance increased steadily thereafter until 2003-2004, when 51.1% of isolates were penicillin nonsusceptible and 53.3% were macrolide resistant. Clindamycin resistance remained low until 2003-2004, when 26.7% of strains were resistant; this was associated with the emergence of multidrug-resistant type 19A strains. This study documents the emergence of resistance over a quarter century among invasive pneumococci in the Cleveland area, as well as the reduction in disease caused by PCV7 serotypes following the introduction of PCV7 in 2000.
Rapid Detection of Triazole Antifungal Resistance in
Aspergillus fumigatus
Authors: Garcia-Effron Guillermo , Dilger Amanda , Alcazar-Fuoli Laura , Park Steven , Mellado Emilia , Perlin David S.
Published: January 2008

Triazole resistance in
Aspergillus fumigatus
is an uncommon but rising phenomenon. Susceptibility testing is rarely performed and can take 48 h or longer, which is an impediment to effective therapy. Molecular diagnostic probing of well-defined resistance mechanisms, which serve as surrogate markers, provides an alternative approach to rapidly (within hours) and efficiently identify resistant strains. The mechanisms of triazole resistance in
A. fumigatus
are limited to amino acid substitutions in the drug target Cyp51A and include amino acid substitutions at the positions Gly 54, Gly 138, Met 220, and Leu 98, coupled with a tandem repetition in the gene promoter. We report the development of a real-time PCR assay utilizing molecular beacons to assess triazole resistance markers in
A. fumigatus
. When combined in a multiplex platform, the assay provides a comprehensive evaluation of drug resistance in
A. fumigatus
.
Recombinant VP4 of Human Rhinovirus Induces Permeability in Model Membranes
Authors: Davis Matthew P. , Bottley Graham , Beales Lucy P. , Killington Richard A. , Rowlands David J. , Tuthill Tobias J.
Published: February 2008

In common with all nonenveloped viruses, the mechanism of picornavirus membrane penetration during cell entry is poorly understood. The small, myristylated capsid protein VP4 has been implicated in this process. Here we show that recombinant VP4 of human rhinovirus 16 has the ability to associate with and induce membrane permeability in otherwise intact liposomes. This provides further evidence that VP4 plays a key role in picornavirus cell entry.
Adenovirus E1B55K Region Is Required To Enhance Cyclin E Expression for Efficient Viral DNA Replication
Authors: Zheng Xinyu , Rao Xiao-Mei , Gomez-Gutierrez Jorge G. , Hao Hongying , McMasters Kelly M. , Zhou H. Sam
Published: January 2008

Adenoviruses (Ads) with E1B55K mutations can selectively replicate in and destroy cancer cells. However, the mechanism of Ad-selective replication in tumor cells is not well characterized. We have shown previously that expression of several cell cycle-regulating genes is markedly affected by the Ad
E1b
gene in WI-38 human lung fibroblast cells (X. Rao, et al., Virology 350:418-428, 2006). In the current study, we show that the Ad E1B55K region is required to enhance cyclin E expression and that the failure to induce cyclin E overexpression due to E1B55K mutations prevents viral DNA from undergoing efficient replication in WI-38 cells, especially when the cells are arrested in the G
0
phase of the cell cycle by serum starvation. In contrast, cyclin E induction is less dependent on the function encoded in the E1B55K region in A549 and other cancer cells that are permissive for replication of E1B55K-mutated viruses, whether the cells are in the S phase or G
0
phase. The small interfering RNA that specifically inhibits cyclin E expression partially decreased viral replication. Our study provides evidence suggesting that E1B55K may be involved in cell cycle regulation that is important for efficient viral DNA replication and that cyclin E overexpression in cancer cells may be associated with the oncolytic replication of E1B55K-mutated viruses.
Envelope Determinants of Equine Infectious Anemia Virus Vaccine Protection and the Effects of Sequence Variation on Immune Recognition
Authors: Tagmyer Tara L. , Craigo Jodi K. , Cook Sheila J. , Even Deborah L. , Issel Charles J. , Montelaro Ronald C.
Published: January 2008

A highly effective attenuated equine infectious anemia virus (EIAV) vaccine (EIAVD9) capable of protecting 100% of horses from disease induced by a homologous Env challenge strain (EIAVPV) was recently tested in ponies to determine the level of protection against divergent Env challenge strains (J. K. Craigo, B. S. Zhang, S. Barnes, T. L. Tagmyer, S. J. Cook, C. J. Issel, and R. C. Montelaro, Proc. Natl. Acad. Sci. USA104:15105-15110, 2007). An inverse correlation between challenge strain Env variation and vaccine protection from disease was observed. Given the striking differences in protective immunity, we hypothesized that analysis of the humoral and cellular immune responses to the Env protein could reveal potential determinants of vaccine protection. Neutralization activity against the homologous Env or challenge strain-specific Env in immune sera from the vaccinated ponies did not correlate with protection from disease. Cellular analysis with Env peptide pools did not reveal an association with vaccine protection from disease. However, when individual vaccine-specific Env peptides were utilized, eight cytotoxic-T-lymphocyte (CTL) peptides were found to associate closely with vaccine protection. One of these peptides also yielded the only lymphoproliferative response associated with protective immunity. The identified peptides spanned both variable and conserved regions of gp90. Amino acid divergence within the principal neutralization domain and the identified peptides profoundly affected immune recognition, as illustrated by the inability to detect cross-reactive neutralizing antibodies and the observation that certain peptide-specific CTL responses were altered. In addition to identifying potential Env determinants of EIAV vaccine efficacy and demonstrating the profound effects of defined Env variation on immune recognition, these data also illustrate the sensitivity offered by individual peptides compared to peptide pools in measuring cellular immune responses in lentiviral vaccine trials.
A Dormant Internal Ribosome Entry Site Controls Translation of Feline Immunodeficiency Virus
Authors: Camerini Valentina , Decimo Didier , Balvay Laurent , Pistello Mauro , Bendinelli Mauro , Darlix Jean-Luc , Ohlmann Théophile
Published: January 2008

The characterization of internal ribosome entry sites (IRESs) in virtually all lentiviruses prompted us to investigate the mechanism used by the feline immunodeficiency virus (FIV) to produce viral proteins. Various in vitro translation assays with mono- and bicistronic constructs revealed that translation of the FIV genomic RNA occurred both by a cap-dependent mechanism and by weak internal entry of the ribosomes. This weak IRES activity was confirmed in feline cells expressing bicistronic RNAs containing the FIV 5′ untranslated region (UTR). Surprisingly, infection of feline cells with FIV, but not human immunodeficiency virus type 1, resulted in a great increase in FIV translation. Moreover, a change in the cellular physiological condition provoked by heat stress resulted in the specific stimulation of expression driven by the FIV 5′ UTR while cap-dependent initiation was severely repressed. These results reveal the presence of a “dormant” IRES that becomes activated by viral infection and cellular stress.
An Overlapping Bacterial Artificial Chromosome System That Generates Vectorless Progeny for Channel Catfish Herpesvirus
Authors: Kunec Dusan , Hanson Larry A. , van Haren Sandra , Nieuwenhuizen I. F. , Burgess Shane C.
Published: January 2008

Herpesviruses are important pathogens of humans and other animals. Herpesvirus infectious clones that can reconstitute phenotypically wild-type (wt) virus are extremely valuable tools for elucidating the roles of specific genes in virus pathophysiology as well as for making vaccines.
Ictalurid herpesvirus 1
(channel catfish herpesvirus [CCV]) is economically very important and is the best characterized of the herpesviruses that occur primarily in bony fish and amphibians. Here, we describe the cloning of the hitherto recalcitrant CCV genome as three overlapping subgenomic bacterial artificial chromosomes (BACs). These clones allowed us to regenerate vectorless wt CCVs with a phenotype that is indistinguishable from that of the wt CCV from which the BACs were derived. To test the recombinogenic systems, we next used the overlapping BACs to construct a full-length CCV BAC by replacing the CCV ORF5 with the BAC cassette and cotransfecting CCO cells. The viral progeny that we used to transform
Escherichia coli
and the resulting BAC had only one of the 18-kb terminal repeated regions. Both systems suggest that one of the terminal repeat regions is lost during the replicative stage of the CCV life cycle. We also demonstrated the feasibility of introducing a targeted mutation into the CCV BAC infectious clone by constructing a CCV ORF12 deletion mutant and showed that ORF12 encodes a nonessential protein for virus replication. This is the first report of the generation of an infectious BAC clone of a member of the fish and amphibian herpesviruses and its use to generate recombinants.
Phylogenetic Evidence against Evolutionary Stasis and Natural Abiotic Reservoirs of Influenza A Virus
Authors: Worobey Michael
Published: January 2008

Zhang et al. (G. Zhang, D. Shoham, D. Gilichinsky, S. Davydov, J. D. Castello, and S. O. Rogers, J. Virol. 80:12229-12235, 2006) have claimed to have recovered influenza A virus RNA from Siberian lake ice, postulating that ice might represent an important abiotic reservoir for the persistence and reemergence of this medically important pathogen. A rigorous phylogenetic analysis of these influenza A virus hemagglutinin gene sequences, however, indicates that they originated from a laboratory reference strain derived from the earliest human influenza A virus isolate, WS/33. Contrary to Zhang et al.'s assertions that the Siberian “ice viruses” are most closely related either to avian influenza virus or to human influenza virus strains from Asia from the 1960s (Zhang et al., J. Virol. 81:2538 [erratum], 2007), they are clearly contaminants from the WS/33 positive control used in their laboratory. There is thus no credible evidence that environmental ice acts as a biologically relevant reservoir for influenza viruses. Several additional cases with findings that seem at odds with the biology of influenza virus, including modern-looking avian influenza virus RNA sequences from an archival goose specimen collected in 1917 (T. G. Fanning, R. D. Slemons, A. H. Reid, T. A. Janczewski, J. Dean, and J. K. Taubenberger, J. Virol. 76:7860-7862, 2002), can also be explained by laboratory contamination or other experimental errors. Many putative examples of evolutionary stasis in influenza A virus appear to be due to laboratory artifacts.
Virological Outcome after Structured Interruption of Antiretroviral Therapy for Human Immunodeficiency Virus Infection Is Associated with the Functional Profile of Virus-Specific CD8+T Cells
Authors: Daucher Marybeth , Price David A. , Brenchley Jason M. , Lamoreaux Laurie , Metcalf Julia A. , Rehm Catherine , Nies-Kraske Elizabeth , Urban Elizabeth , Yoder Christian , Rock Diane , Gumkowski Julie , Betts Michael R. , Dybul Mark R. , Douek Daniel C.
Published: January 2008

A clear understanding of the antiviral effects of CD8+T cells in the context of chronic human immunodeficiency virus (HIV) infection is critical for the development of prophylactic vaccines and therapeutics designed to support T-cell-mediated immunity. However, defining the potential correlates of effective CD8+T-cell immunity has proven difficult; notably, comprehensive analyses have demonstrated that the size and shape of the CD8+T-cell response are not necessarily indicative of efficacy determined by measures of plasma viral load. Here, we conducted a detailed quantitative and qualitative analysis of CD8+T-cell responses to autologous virus in a cohort of six HIV-infected individuals with a history of structured interruption of antiretroviral therapy (ART) (SIT). The magnitude and breadth of the HIV-specific response did not, by themselves, explain the changes observed in plasma virus levels after the cessation of ART. Furthermore, mutational escape from targeted epitopes could not account for the differential virological outcomes in this cohort. However, the functionality of HIV-specific CD8+T-cell populations upon antigen encounter, determined by the simultaneous and independent measurement of five CD8+T-cell functions (degranulation and gamma interferon, macrophage inflammatory protein 1β, tumor necrosis factor alpha, and interleukin-2 levels) reflected the emergent level of plasma virus, with multiple functions being elicited in those individuals with lower levels of viremia after SIT. These data show that the quality of the HIV-specific CD8+T-cell response, rather than the quantity, is associated with the dynamics of viral replication in the absence of ART and suggest that the effects of SIT can be assessed by measuring the functional profile of HIV-specific CD8+T cells.
Systematic Mutagenesis of the Murine Gammaherpesvirus 68 M2 Protein Identifies Domains Important for Chronic Infection
Authors: Herskowitz Jeremy H. , Siegel Andrea M. , Jacoby Meagan A. , Speck Samuel H.
Published: January 2008

Murine gammaherpesvirus 68 (MHV68) infection of inbred mice represents a genetically tractable small-animal model for assessing the requirements for the establishment of latency, as well as reactivation from latency, within the lymphoid compartment. By day 16 postinfection, MHV68 latency in the spleen is found in B cells, dendritic cells, and macrophages. However, as with Epstein-Barr virus, by 3 months postinfection MHV68 latency is predominantly found in isotype-switched memory B cells. The MHV68 M2 gene product is a latency-associated antigen with no discernible homology to any known cellular or viral proteins. However, depending on experimental conditions, the M2 protein has been shown to play a critical role in both the efficient establishment of latency in splenic B cells and reactivation from latently infected splenic B cells. Inspection of the sequence of the M2 protein reveals several hallmarks of a signaling molecule, including multiple PXXP motifs and two potential tyrosine phosphorylation sites. Here, we report the generation of a panel of recombinant MHV68 viruses harboring mutations in the M2 gene that disrupt putative functional motifs. Subsequent analyses of the panel of M2 mutant viruses revealed a functionally important cluster of PXXP motifs in the C-terminal region of M2, which have previously been implicated in binding Vav proteins (P. A. Madureira, P. Matos, I. Soeiro, L. K. Dixon, J. P. Simas, and E. W. Lam, J. Biol. Chem. 280:37310-37318, 2005; L. Rodrigues, M. Pires de Miranda, M. J. Caloca, X. R. Bustelo, and J. P. Simas, J. Virol. 80:6123-6135, 2006). Further characterization of two adjacent PXXP motifs in the C terminus of the M2 protein revealed differences in the functions of these domains in M2-driven expansion of primary murine B cells in culture. Finally, we show that tyrosine residues 120 and 129 play a critical role in both the establishment of splenic latency and reactivation from latency upon explant of splenocytes into tissue culture. Taken together, these analyses will aide future studies for identifying M2 interacting partners and B-cell signaling pathways that are manipulated by the M2 protein.
Expansion and Exhaustion of T-Cell Responses during Mutational Escape from Long-Term Viral Control in Two DNA/Modified Vaccinia Virus Ankara-Vaccinated and Simian-Human Immunodeficiency Virus SHIV-89.6P-Challenged Macaques
Authors: Sadagopal Shanmugalakshmi , Amara Rama Rao , Kannanganat Sunil , Sharma Sunita , Chennareddi Lakshmi , Robinson Harriet L.
Published: January 2008

In this study, we monitored the temporal breadths, frequencies, and functions of antiviral CD4 and CD8 T cells in 2 of 22 DNA/modified vaccinia virus Ankara-vaccinated macaques that lost control of a simian-human immunodeficiency virus 89.6P challenge by 196 weeks postchallenge. Our results show that both mutation and exhaustion contributed to escape. With the reappearance of viremia, responding CD8 and CD4 T cells underwent an initial increase and then loss of breadth and frequency. Antiviral gamma interferon (IFN-γ)- and interleukin 2-coproducing cells were lost before IFN-γ-producing cells and CD4 cells before CD8 cells. At euthanasia, all CD8, but no CD4, Gag epitopes detected during long-term control contained mutations.
Human HLA-DR Transgenes Protect Mice from Fatal Virus-Induced Encephalomyelitis and Chronic Demyelination
Authors: Rodriguez Moses , Zoecklein Laurie , Kerkvliet Jason G. , Pavelko Kevin D. , Papke Louisa , Howe Charles L. , Pease Larry R. , David Chella
Published: January 2008

We evaluated the participatory role of human HLA-DR molecules in control of virus from the central nervous system and in the development of subsequent spinal cord demyelination. The experiments utilized intracranial infection with Theiler's murine encephalomyelitis virus (TMEV), a picornavirus that, in some strains of mice, results in primary demyelination. We studied DR2 and DR3 transgenic mice that were bred onto a combined class I-deficient mouse (beta-2 microglobulin deficient; β2m0) and class II-deficient mouse (Aβ0) of theH-2bbackground. Aβ0.β2m0mice infected with TMEV died within 18 days of infection. These mice showed severe encephalomyelitis due to rapid replication of virus genome. In contrast, transgenic mice with insertion of a single human class II major histocompatibility complex (MHC) gene (DR2 or DR3) survived the acute infection. DR2 and DR3 mice controlled virus infection by 45 days and did not develop spinal cord demyelination. Levels of virus RNA were reduced in HLA-DR transgenic mice compared to Aβ0.β2m0mice. Virus-neutralizing antibody responses did not explain why DR mice survived the infection and controlled virus replication. However, DR mice showed an increase in gamma interferon and interleukin-2 transcripts in the brain, which were associated with protection. The findings support the hypothesis that the expression of a single human class II MHC molecule can, by itself, influence the control of an intracerebral pathogen in a host without a competent class I MHC immune response. The mechanism of protection appears to be the result of cytokines released by CD4+T cells.
Redundancy and Plasticity of Neutralizing Antibody Responses Are Cornerstone Attributes of the Human Immune Response to the Smallpox Vaccine
Authors: Benhnia Mohammed Rafii-El-Idrissi , McCausland Megan M. , Su Hua-Poo , Singh Kavita , Hoffmann Julia , Davies D. Huw , Felgner Philip L. , Head Steven , Sette Alessandro , Garboczi David N. , Crotty Shane
Published: January 2008

The smallpox vaccine is widely considered the gold standard for human vaccines, yet the key antibody targets in humans remain unclear. We endeavored to identify a stereotypic, dominant, mature virion (MV) neutralizing antibody target in humans which could be used as a diagnostic serological marker of protective humoral immunity induced by the smallpox vaccine (vaccinia virus [VACV]). We have instead found that diversity is a defining characteristic of the human antibody response to the smallpox vaccine. We show that H3 is the most immunodominant VACV neutralizing antibody target, as determined by correlation analysis of immunoglobulin G (IgG) specificities to MV neutralizing antibody titers. It was determined that purified human anti-H3 IgG is sufficient for neutralization of VACV; however, depletion or blockade of anti-H3 antibodies revealed no significant reduction in neutralization activity, showing anti-H3 IgG is not required in vaccinated humans (or mice) for neutralization of MV. Comparable results were obtained for human (and mouse) anti-L1 IgG and even for anti-H3 and anti-L1 IgG in combination. In addition to H3 and L1, human antibody responses to D8, A27, D13, and A14 exhibited statistically significant correlations with virus neutralization. Altogether, these data indicate the smallpox vaccine succeeds in generating strong neutralizing antibody responses not by eliciting a stereotypic response to a single key antigen but instead by driving development of neutralizing antibodies to multiple viral proteins, resulting in a “safety net” of highly redundant neutralizing antibody responses, the specificities of which can vary from individual to individual. We propose that this is a fundamental attribute of the smallpox vaccine.
The VP7 Genes of Two G9 Rotaviruses Isolated in 1980 from Diarrheal Stool Samples Collected in Washington, DC, Are Unique Molecularly and Serotypically
Authors: Cao Dianjun , Santos Norma , Jones Ronald W. , Tatsumi Masatoshi , Gentsch Jon R. , Hoshino Yasutaka
Published: January 2008

In a retrospective study of archival diarrheal stool samples collected from 1974 to 1991 at Children's Hospital National Medical Center, Washington, DC, we detected three genotype G9P[8] viruses in specimens collected in 1980, which represented the earliest human G9 viruses ever isolated. The VP7 genes of two culture-adapted 1980 G9 viruses were phylogenetically related closely to the lineage 2 G9 virus VP7 gene. Unexpectedly, however, the VP7s of the 1980 G9 viruses were more closely related serotypically to lineage 3 VP7s than to lineage 2 VP7, which may be supported by amino acid sequence analyses of the VP7 proteins.
Evaluation of the Human Transmission Risk of an Atypical Bovine Spongiform Encephalopathy Prion Strain
Authors: Kong Qingzhong , Zheng Mengjie , Casalone Cristina , Qing Liuting , Huang Shenghai , Chakraborty Bikram , Wang Ping , Chen Fusong , Cali Ignazio , Corona Cristiano , Martucci Francesca , Iulini Barbara , Acutis Pierluigi , Wang Lan , Liang Jingjing , Wang Meiling , Li Xinyi , Monaco Salvatore , Zanusso Gianluigi , Zou Wen-Quan , Caramelli Maria , Gambetti Pierluigi
Published: January 2008

Bovine spongiform encephalopathy (BSE), the prion disease in cattle, was widely believed to be caused by only one strain, BSE-C. BSE-C causes the fatal prion disease named new variant Creutzfeldt-Jacob disease in humans. Two atypical BSE strains, bovine amyloidotic spongiform encephalopathy (BASE, also named BSE-L) and BSE-H, have been discovered in several countries since 2004; their transmissibility and phenotypes in humans are unknown. We investigated the infectivity and human phenotype of BASE strains by inoculating transgenic (Tg) mice expressing the human prion protein with brain homogenates from two BASE strain-infected cattle. Sixty percent of the inoculated Tg mice became infected after 20 to 22 months of incubation, a transmission rate higher than those reported for BSE-C. A quarter of BASE strain-infected Tg mice, but none of the Tg mice infected with prions causing a sporadic human prion disease, showed the presence of pathogenic prion protein isoforms in the spleen, indicating that the BASE prion is intrinsically lymphotropic. The pathological prion protein isoforms in BASE strain-infected humanized Tg mouse brains are different from those from the original cattle BASE or sporadic human prion disease. Minimal brain spongiosis and long incubation times are observed for the BASE strain-infected Tg mice. These results suggest that in humans, the BASE strain is a more virulent BSE strain and likely lymphotropic.
Single-Dose Protection againstPlasmodium bergheiby a Simian Adenovirus Vector Using a Human Cytomegalovirus Promoter Containing Intron A
Authors: Sridhar S. , Reyes-Sandoval A. , Draper S. J. , Moore A. C. , Gilbert S. C. , Gao G. P. , Wilson J. M. , Hill A. V. S.
Published: February 2008

Human adenovirus serotype 5 (AdH5) vector vaccines elicit strong immune responses to the encoded antigen and have been used in various disease models. We designed AdH5 vectors expressing antigen under the control of a human cytomegalovirus (HCMV) immediate-early promoter containing its intron A sequence. The transcriptional levels of antigen and immune responses to antigen for vectors with the HCMV promoter with the intron A sequence (LP) were greater than those for AdH5 vectors using the HCMV promoter sequence without intron A (SP). We compared an E1E3-deleted AdH5 adenoviral vector, which affords more space for insertion of foreign sequences, and showed it to be as immunogenic as an E1-deleted AdH5 vector. Neutralizing antibodies to AdH5 limit the efficacy of vaccines based on the AdH5 serotype, and simian adenoviral vectors offer an attractive option to overcome this problem. We constructed E1E3-deleted human and simian adenoviral vectors encoding the pre-erythrocytic-stage malarial antigenPlasmodium bergheicircumsporozoite protein. We compared the immunogenicity and efficacy of AdC6, a recombinant simian adenovirus serotype 6 vector, in a murine malaria model to those of AdH5 and the poxviral vectors MVA and FP9. AdC6 induced sterile protection from a single dose in 90% of mice, in contrast to AdH5 (25%) and poxviral vectors MVA and FP9 (0%). Adenoviral vectors maintained potent CD8+T-cell responses for a longer period after immunization than did poxviral vectors and mainly induced an effector memory phenotype of cells. Significantly, AdC6 was able to maintain protection in the presence of preexisting immunity to AdH5.
On the Structure of Tri- and Tetrahydroxolead(II) Complex Anions
Authors: Šoralová Stanislava , Breza Martin
Published: January 2008

Optimal geometries and corresponding electronic structures of various [Pb(OH)3]- and [Pb(OH)4]2- conformational isomers are investigated by the B3LYP and MP2 treatments. Unlike highly symmetric [Pb(OH)3]- structure (C3 symmetry), the most stable [Pb(OH)4]2- conformational isomer has only C2 symmetry. Hydrogen bonds exhibit a lower influence on the stereochemistry of lead(II) hydroxocomplexes in comparison with the steric effect of the Pb(II) lone electron pair. The picture of the Pb(II) lone electron pair cannot explain the lowered symmetry of isolated [Pb(OH)4]2- complexes with four equivalent hydrogen bonds.
BIOSYSTEMATIC STUDIES ON XANTHIUM: TAXONOMIC APPRAISAL AND ECOLOGICAL STATUS
Authors: Löve Doris , Dansereau Pierre
Published: January 2008

The following paper is an evaluation of the taxonomic and ecological status of the genus Xanthium L. A review of its systematics demonstrates that many so-called "species" described on material from Europe actually have their origin in America, except one, X. strumarium s. str., which seems to have a Mediterranean–European center of dispersal. Another conclusion drawn is that Xanthium consists of only two distinct species: X. spinosum L. and X. strumarium L. The former is a relatively stable species, the latter an enormously variable one readily subdivided into a number of minor taxonomic entities.Ecologically, in eastern North America at least, Xanthium is primarily a beach plant, which prefers open habitats and succumbs to crowding. The seeds are most often dispersed by water and wind. It enters easily into ruderal habitats, but only as long as these are open and unshaded.The generalized short-day flowering response in this genus supports our hypothesis that Xanthium has a tropical–subtropical origin, and we feel that it has its center in Central and/or South America, whence it has spread over the continents north and southward.There is no evidence for any sterility barriers separating the entities of X. strumarium, but we feel that an intense inbreeding with an occasional outbreeding is responsible for the enormous variation, often resulting in small, local, but unstable taxa.
THE RELATION OF BARK MOISTURE TO THE DEVELOPMENT OF CANKER DISEASES CAUSED BY NATIVE, FACULTATIVE PARASITES: I. CRYPTODIAPORTHE CANKER ON WILLOW
Authors: Bier John E.
Published: January 2008

A close correlation was found to exist between the development of the willow bark canker, caused by Cryptodiaporthe salicina (Curr.) Weh., and the moisture content of the bark. When this was expressed as a percentage of the amount of water required to saturate the sample under experimental conditions, relative turgidities of 80% or more inhibited canker development which, however, occurred normally at lower percentages. Studies of the epidemiology of this disease in the Vancouver area afforded evidence in support of the limiting effect of bark moisture on canker development. Thus during the dormant season of 1957–58 the monthly average temperature was significantly higher than the minimum temperature for the growth of C. salicina on potato dextrose agar and the relative turgidity did not reach the inhibiting value of 80%. Cankers continued to develop throughout this period. During the growing season while temperatures were still more favorable for fungus development no extension of cankers occurred, apparently because, during the growing period, the relative turgidity was in excess of 80%. Canker development was prevented during the winter by placing dormant twigs in water, which likewise increased the moisture content of the bark above the 80% level.