bluuebunny/crossref_metadata_2025 huggingface dataset:
Visualising Interaction Effects
Authors: Woodward Phil , Whitlock Mark
Published: February 2004

In drug discovery, statisticians often work with biologists and chemists to uncover relationships between the various chemical properties and the biological effects of compounds. The aim is to “design” drugs that have exactly the desired pharmaceutical effects. Phil Woodward and Mark Whitlock of Pfizer Global R&D show how a graph can uncover deeply hidden relationships and guide chemists in their efforts to find the next blockbuster drug.
Talk and Travel
Authors: Lievesley Denise
Published: February 2004

Denise Lievesley explains how she came to be in her present post as Director of the Institute for Statistics at UNESCO and describes some aspects of the job which she finds particularly challenging.
Agricultural Data Quality
Authors: Neil Stuart
Published: February 2004

Since the late 19th century, the Agricultural Census has been an important source of data on land use and numbers of livestock and farm workers. It works well as a general source of large area results, but in late 2003, in response to customer demand to make data available at smaller geographical scales, the Welsh Assembly released a spreadsheet of results at the small area level from the 2002 Agricultural Census. In this case study, Stuart Neil discusses the issues of data quality that arose in compiling these data.
Managing by Fact
Authors: Caulcutt Roland
Published: February 2004

Some organisations claim to have a “management-by-fact” culture, meaning that managerial decisions are based on data, rather than assumptions or opinions. Roland Caulcutt explains how an organisation can work towards this goal by using a simple graphical technique.
Differences in Retrospective Perceptions of Parenting of Male and Female Inmates and Non‐Inmates*
Authors: Chipman Stacey , Olsen Susanne Frost , Klein Shirley , Hart Craig H. , Robinson Clyde C.
Published: February 2004

One hundred twenty‐eight inmates and 337 non‐inmates completed parenting questionnaires that assessed retrospective perceptions of their fathers' and mothers' authoritative, authoritarian, and permissive parenting styles, as well as the stylistic dimensions found within the three styles. Inmates reported higher incidence than non‐inmates of both authoritarian and permissive parenting styles and dimensions, and lower incidence of the authoritative parenting style and dimensions. Significant interactions between inmate status and parent gender and child gender were also found. Recommendations for family life educators in prison settings are outlined.
Parenting Self‐Efficacy Among Mothers of School‐Age Children: Conceptualization, Measurement, and Correlates*
Authors: Coleman Priscilla K. , Karraker Katherine Hildebrandt
Published: February 2004

Relationships among parenting self‐efficacy, general self‐efficacy, child and maternal characteristics, and parenting satisfaction in 145 mothers of school‐aged children were examined. Higher parenting self‐efficacy was observed in mothers of less emotional and more sociable children, and among mothers who were better educated, had higher family incomes, and reported more previous experience with children. Higher parenting self‐efficacy and several mother and child variables predicted greater satisfaction with parenting. Influences of mothers' experience with children other than their own and maternal education on parenting satisfaction were mediated by parenting self‐efficacy. Suggestions concerning the conceptualization and measurement of parenting self‐efficacy are provided.
Interparental Conflict and Parenting Behaviors: A Meta‐Analytic Review
Authors: Krishnakumar Ambika , Buehler Cheryl
Published: February 2004

The purpose of this study is to examine the association between interparental conflict and parenting using meta‐analytic review techniques. One‐hundred and thirty‐eight effect sizes from 39 studies are analyzed. The overall average weighted effect size is −.62, indicating a moderate association and support for the spillover hypothesis. The parenting behaviors most impacted by interparental conflict are harsh discipline and parental acceptance. Several moderating effects for subject and method characteristics are significant.
Parent‐Child Social Play in a Children's Museum*
Authors: Shine Stephanie , Acosta Teresa Y.
Published: February 2004

Two studies examined pretend play in families visiting a children's museum. In Study One, families were observed visiting an exhibit inviting visitors to try on roles. Parent‐child play was found to be brief, sporadic, and non‐contingent. In Study Two, families were invited to visit four exhibits and parents were interviewed. Parents were found to prompt, support, and observe more than engage in pretend play. Implications for family educators and museum designers are discussed.
First Comes Work, Then Comes Marriage: Future Orientation Among African American Young Adolescents*
Authors: McCabe Kristen , Barnett Douglas
Published: February 2004

In this study we gathered quantitative and qualitative information on the thoughts and feelings of 72 low income, African American sixth‐graders about their future careers, romantic relationships, and family relationships. Interviews were scored along several dimensions of future orientation: detail, optimism, pessimism, realism, and control beliefs. Children also rated the probability that various future life events would occur. Repeated Measures ANOVAs revealed that sixth‐graders were more detailed, optimistic, and realistic about their future careers than their romantic and family relationships and felt that they had more control over careers than relationships. No gender differences were found across the domains of future orientation. Descriptive information about at‐risk adolescents' future orientations is presented. Results are discussed in terms of implications for intervention with at‐risk youth.
Raising Awareness About Marital Expectations: Are Unrealistic Beliefs Changed by Integrative Teaching?*
Authors: Sharp Elizabeth A. , Ganong Lawrence H.
Published: February 2004

This study explores the effects of integrative teaching on college students' unrealistic and romantic beliefs about marriage. The hypothesis that students in the integrative teaching group would significantly lower unrealistic beliefs was partially supported, with students in the integrative teaching group significantly lowering their romantic beliefs. Unrealistic relationship beliefs decreased for both comparison and integrative teaching groups. Women in both groups ascribe to fewer unrealistic relationship and romantic beliefs. Implications of these findings are discussed.
Why Family Professionals Can No Longer Ignore Violence Toward Animals*
Authors: Flynn Clifton P.
Published: February 2004

The issue of violence to animals has been virtually ignored by family scholars and other family professionals. After looking at why animal abuse has not received attention, it is argued that those who study and work with families need to attend to animal abuse for seven reasons: (a) animal abuse is a serious antisocial behavior by children and adolescents; (b) it is a relatively common childhood occurrence; (c) it has potential negative developmental consequences; (d) violence toward animals is related to interpersonal violence; (e) it is connected to and may be a marker of family violence; (f) the well‐being of companion animals is being neglected; and (g) it will help achieve a less violent society. The implications for research, policy, counseling and human services, and family life education are discussed.
Parenting Expectations and Concerns of Fathers and Mothers of Newborn Infants*
Authors: Litton Fox Greer , Bruce Carol , Combs‐Orme Terri
Published: February 2004

Mothers and their partners were interviewed in the Labor and Delivery units of two hospitals in Tennessee. An association was found between level of mother's concern about caring for her child and a mismatch between partners' expectations for father's helpful involvement in certain aspects of parenting. The perinatal period while parents are in health care settings provides opportune time for family life education approaches that explore couples' expectations for paternal involvement and their parenting concerns.
Adolescent Sexuality and Parent‐Adolescent Processes: Promoting Healthy Teen Choices*
Authors: Meschke Laurie L. , Bartholomae Suzanne , Zentall Shannon R.
Published: February 2004

Trends in adolescent sexual health, the relation between parenting and adolescent sexual outcomes, and adolescent sexuality interventions with a parent component are reviewed. American adolescents have higher rates of unprotected sex and STI contraction than adults and nine times the teen pregnancy rate of their European counterparts. Parenting efforts are related to adolescent sexual behavior. The review of 19 relevant programs supports the incorporation of theory and the ecological model in program design and evaluation.
Mothers' Experiences of an Adult Child's HIV/AIDS Diagnosis: Maternal Responses to and Resolutions of Accountability for AIDS*
Authors: Thompson Elizabeth A.
Published: February 2004

Based on 13 in‐depth interviews, this paper addresses mothers' initial reactions to an adult child's HIV diagnosis. Mothers described responses that included intense personal and emotional reactions. Additionally, mothers acknowledged the importance of resolving initial blame paradigms for the diagnosis, which included facing and resolving feelings of personal responsibility for the adult child's illness. Addressing feelings of blame and initial emotional reactions helped mothers to play active roles in the social support of their children.
An Examination of the Trajectory of the Adult Child's Caregiving for an Elderly Parent
Authors: Cicirelli Victor G.
Published: February 2004

Study objective was to delineate stages in filial role development from recognition of responsibility to provision of help. Fifty‐three adult child‐elderly parent pairs reported on parent health status and child filial behaviors. Child concern was unrelated to parent health status; urging parent to modify health was moderately related to health status; child's action to provide help was related only to parent's functional adequacy (p < .05). Pair members' reports agreed most strongly regarding functional adequacy.
Strategies for Racial Identity Development: Narratives of Black and White Women in Interracial Partner Relationships*
Authors: Hill Miriam R. , Thomas Volker
Published: February 2004

This exploratory qualitative study used individual interviews and a focus group to investigate how women in Black‐White interracial heterosexual partner relationships retrospectively described their racial identity development over the course of the relationships. Racial identity development, social constructionist, and feminist theories guided the grounded theory methodology. Participants described a process of restorying constraining narratives of racial identity into empowering racial identities through three types of strategies: blocking strategies, transforming strategies, and generating strategies.
Avoidance and Attacking Conflict‐Resolution Strategies Among Married Couples: Relations to Depressive Symptoms and Marital Satisfaction*
Authors: Marchand Jennifer F. , Hock Ellen
Published: February 2004

This study examined the relation of depressive symptoms and marital satisfaction to conflict‐resolution strategies (avoidance and attacking) in a sample of 40 married couples. Using hierarchical regression analyses, models were tested wherein avoidance and attacking scores were regressed on husbands' and wives' depressive symptoms and marital satisfaction scores. Depressive symptoms and marital satisfaction were powerful predictors of conflict‐resolution strategies; however, different predictors were noted for avoidance and attacking conflict‐resolution strategies. Gender differences were also revealed.
Lodge Programs Serving Family Functions for People with Psychiatric Disabilities*
Authors: Onaga Esther E. , McKinney Kathleen G. , Pfaff Judy
Published: February 2004

People affiliated with lodges, a community program for people with psychiatric disabilities, were interviewed through small group face‐to‐face and telephone interviews about their perceptions of promising practices. Responses from the interviews appeared to fit the theme of the lodge serving many of the functions of a family. Relevant excerpts from the interviews were used to supplement this broad theme and implications for practice are discussed in terms of competency‐based outcomes.
The Care Continues: Responsibility for Elderly Relatives Before and After Admission to a Long Term Care Facility*
Authors: Keefe Janice , Fancey Pamela
Published: February 2004

Interviews with 214 family members are analyzed to investigate how caregiving changes from the community to the long term care (ltc) facility and to understand family member's responsibility toward elderly relatives in ltc facilities. Family responsibilities can be categorized as ‘indirect' including an overseer of care or ‘direct' including performing specific tasks. Findings suggest that emotional support needs to be incorporated into measures of caregiving. Research implications include the need for increased education for family on health care issues and a greater recognition of their resourcefulness for staff.
Adolescent Childbearing, Poverty, and Siblings: Taking New Direction From the New Literature*
Authors: East Patricia L. , Jacobson Leanne J.
Published: February 2004

This article critically appraises the sibling‐comparison method by pointing to the following limitations: (1) it assumes within‐family homogeneity; (2) it neglects naturally occurring heterogeneity across siblings; (3) it overlooks the unique effects of a teen's childbearing for her family and siblings; (4) it underappreciates the selectivity of sisters of teenage mothers who delay childbearing; and, (5) it ignores differences in outcomes by sisters' birth order and age spacing. Directions for future research stemming from this new literature are discussed.
Connecting Research and Policymaking: Implications for Theory and Practice from the Family Impact Seminars*
Authors: Bogenschneider Karen , Olson Jonathan R. , Linney Kirsten D. , Mills Jessica
Published: February 2004

This paper addresses a conundrum that merits scholarly attention—why social scientists' ability to generate high quality research has outpaced their ability to disseminate research into the policymaking process. The paper describes Family Impact Seminars, a series of seminars, briefing reports, and follow‐up activities that provide up‐to‐date, solution‐oriented information to state policymakers. In support of the proposed “three‐communities” theory, the utilization of research in policymaking appears to depend upon several pragmatic practices and procedures, ten which are detailed in the paper.
An Odd Couple with Promise: Researchers and Practitioners in Evaluation Settings*
Authors: Myers‐Walls Judith A.
Published: February 2004

Evaluation of programs for families continues to grow in importance. The best evaluation studies involve collaborations between evaluation researchers and practitioners, but the two groups represent different cultures. Cultural differences are seen in temporal orientation, cognitive resources, values and definitions of excellence, patterns of communication, daily life styles, and use of tools. The author provides eight suggested steps to improve collaboration through the determination of shared goals, clarification of boundaries, and improved communication.
Genetic “Mysteries” and International Adoption: The Cultural Impact of Biomedical Technologies on the Adoptive Family Experience*
Authors: Lebner Ashley
Published: February 2004

This paper argues that the increasing medicalization and geneticization of North American society may be influencing how and why adoptive families think—and worry—about their children's birthparents, their children's ‘health risks’, and about their own role as parents in genetic terms. It further discusses why these processes may be causing adoptive parents unnecessary anxieties. It suggests that family professionals and social workers should be aware of the effects of these socio‐cultural processes and of the real limitations of genetic techniques to predict, diagnose, and cure disease in order to better respond to prospective adoptive parents' need for support and information.
Adoptive Identity: How Contexts Within and Beyond the Family Shape Developmental Pathways*
Authors: Grotevant Harold D. , Dunbar Nora , Kohler Julie K. , Esau Amy M. Lash
Published: February 2004

The focus of this paper is adoptive identity, the sense of who one is as an adopted person. The paper first considers how identity has been shaped by recent social changes, and then explores the meaning of adoptive identity and its developmental course. Three contexts of development are examined: intrapsychic, the family environment, and contexts beyond the family, including relationships with friends, connection to community, and culture. Implications for professionals who work with adopted persons and for needed research are also discussed.
Adjustment Among Adopted Children: The Role of Maternal Self‐Reflectiveness*
Authors: Priel Beatriz , Melamed‐Hass Sigal , Besser Avi , Kantor Bela
Published: February 2004

The maternal self‐reflective function was assumed to affect maternal perceptions of adopted children's adjustment. In a sample of Israeli mothers of school‐aged, non‐referred children, self‐reflectiveness scores were found to discriminate between adoptive (N= 50) and non‐adoptive (N= 80) participants, and affect the rate of perceived externalizing behaviors. Specific protective and risk factors that characterize adoptive motherhood are discussed, indicating their implications for therapeutic intervention.
Birthmother Perceptions of the Psychologically Present Adopted Child: Adoption Openness and Boundary Ambiguity*
Authors: Fravel Deborah Lewis , McRoy Ruth G. , Grotevant Harold D.
Published: February 2004

Secondary analysis of interviews with 163 birthmothers revealed that the adopted child remains psychologically present. Tenindicatorsof psychological presence were identified. Indicators related toroleswere more salient the more open the adoption, andsupernatural referentswere more salient when a birthmother once had mediated communication but now has none.Degreeof psychological presence was highest in fully‐disclosed adoptions and lower in ongoing‐mediated, confidential, and time‐limited‐mediated adoptions, respectively.Valencewas generally positive, but more so in fully‐disclosed adoptions.
Openness and Contact in Foster Care Adoptions: An Eight‐Year Follow‐Up*
Authors: Frasch Karie M. , Brooks Devon , Barth Richard P.
Published: February 2004

This study examines openness and contact in 231 foster care adoptions from the California Long‐Range Adoption Study (CLAS), an eight‐year prospective longitudinal study. Data were collected using three waves of mailed questionnaires completed by the adoptive parent. Findings indicate that while the practice of openness continues to evolve for most families, there is remarkable stability in levels of contact and communication with the child's biological family, especially in the last four years of the study.
Building Effective Post‐Adoption Services: What is the Empirical Foundation?*
Authors: Barth Richard P. , Miller Julie M.
Published: February 2004

While adoptions in general are highly successful, families do experience disappointment and disruption, outcomes that may be reduced by provision of post‐adoption services. Studies show that adoptive parents request a variety of services, yet few demonstration projects have been done to evaluate their effectiveness. In this paper, we recognize the predominance of attachment theory in post‐adoptive services and identify alternative approaches that may have a better fit with the needs and preferences identified by families. We also identify service adaptations for adoptive families that may amplify the power of existing service programs.
Deterrents to Intercountry Adoption in Britain
Authors: Hayes Peter
Published: February 2004

Some local authority social workers in Britain have used their responsibility to make parental assessments to deter parents from adopting abroad. Prospective parents of foreign children may respond to these deterrents by making unauthorized adoptions. Central government officials have condemned both unauthorized adoptions and the obstructive policies towards intercountry adoption found in some local authorities. Prospects for reform depend partly on changing attitudes, and partly on expanding the role of independent intercountry adoption agencies.
Budding of PPxY-Containing Rhabdoviruses Is Not Dependent on Host Proteins TGS101 and VPS4A
Authors: Irie Takashi , Licata Jillian M. , McGettigan James P. , Schnell Matthias J. , Harty Ronald N.
Published: February 2004

Viral matrix proteins of several enveloped RNA viruses play important roles in virus assembly and budding and are by themselves able to bud from the cell surface in the form of lipid-enveloped, virus-like particles (VLPs). Three motifs (PT/SAP, PPxY, and YxxL) have been identified as late budding domains (L-domains) responsible for efficient budding. L-domains can functionally interact with cellular proteins involved in vacuolar sorting (VPS4A and TSG101) and endocytic pathways (Nedd4), suggesting involvement of these pathways in virus budding. Ebola virus VP40 has overlapping PTAP and PPEY motifs, which can functionally interact with TSG101 and Nedd4, respectively. As for vesicular stomatitis virus (VSV), a PPPY motif within M protein can interact with Nedd4. In addition, M protein has a PSAP sequence downstream of the PPPY motif, but the function of PSAP in budding is not clear. In this study, we compared L-domain functions between Ebola virus and VSV by constructing a chimeric M protein (M40), in which the PPPY motif of VSV M is replaced by the L domains of VP40. The budding efficiency of M40 was 10-fold higher than that of wild-type (wt) M protein. Overexpression of a dominant negative mutant of VPS4A or depletion of cellular TSG101 reduced the budding of only M40-containing VLPs but not that of wt M VLPs or live VSV. These findings suggest that the PSAP motif of M protein is not critical for budding and that there are fundamental differences between PTAP-containing viruses (Ebola virus and human immunodeficiency virus type 1) and PPPY-containing viruses (VSV and rabies virus) regarding their dependence on specific host factors for efficient budding.
Neutralizing Antibodies and CD8
+
T Lymphocytes both Contribute to Immunity to Adenovirus Serotype 5 Vaccine Vectors
Authors: Sumida Shawn M. , Truitt Diana M. , Kishko Michael G. , Arthur Janelle C. , Jackson Shawn S. , Gorgone Darci A. , Lifton Michelle A. , Koudstaal Wouter , Pau Maria G. , Kostense Stefan , Havenga Menzo J. E. , Goudsmit Jaap , Letvin Norman L. , Barouch Dan H.
Published: February 2004

The high prevalence of preexisting immunity to adenovirus serotype 5 (Ad5) in human populations will likely limit the immunogenicity and clinical utility of recombinant Ad5 vector-based vaccines for human immunodeficiency virus type 1 and other pathogens. Ad5-specific neutralizing antibodies (NAbs) are thought to contribute substantially to anti-Ad5 immunity, but the potential importance of Ad5-specific T lymphocytes in this setting has not been fully characterized. Here we assess the relative contributions of Ad5-specific humoral and cellular immune responses in blunting the immunogenicity of a rAd5-Env vaccine in mice. Adoptive transfer of Ad5-specific NAbs resulted in a dramatic abrogation of Env-specific immune responses following immunization with rAd5-Env. Interestingly, adoptive transfer of Ad5-specific CD8
+
T lymphocytes also resulted in a significant and durable suppression of rAd5-Env immunogenicity. These data demonstrate that NAbs and CD8
+
T lymphocytes both contribute to immunity to Ad5. Novel adenovirus vectors that are currently being developed to circumvent the problem of preexisting anti-Ad5 immunity should therefore be designed to evade both humoral and cellular Ad5-specific immune responses.
Binding to Decay-Accelerating Factor Is Not Required for Infection of Human Leukocyte Cell Lines by Enterovirus 70
Authors: Haddad Alain , Nokhbeh M. Reza , Alexander David A. , Dawe Sandra J. , Grisé Christine , Gulzar Naveed , Dimock Kenneth
Published: February 2004

Enterovirus 70 (EV70) is one of several human enteroviruses that exhibit a propensity for infecting the central nervous system (CNS). The mechanisms by which neurotropic enteroviruses gain access to and invade the CNS are poorly understood. One possibility is that circulating leukocytes become infected and carry neurotropic enteroviruses to the CNS. We examined the ability of EV70 to infect cell lines derived from lymphoid, myeloid, and monocytic lineages. Most leukocyte cell lines tested bound radiolabeled EV70 and were permissive for EV70 replication, suggesting that EV70, in contrast to other enteroviruses, has an in vitro tropism that includes lymphoid, monocytic, and myeloid cell lines. For some of the cell lines, virus binding and infection correlated with surface expression of decay-accelerating factor (DAF), an attachment protein for EV70 on HeLa cells. However, EV70 also adsorbed to and infected cell lines that expressed little or no DAF. In contrast to what was observed for HeLa cells, neither DAF-specific monoclonal antibodies nor phosphatidylinositol-specific phospholipase C treatment inhibited EV70 binding to permissive leukocyte cell lines, and antibody blockade of DAF had little or no effect on EV70 replication. We also found that neither the human coxsackievirus-adenovirus receptor nor intercellular cell adhesion molecule 1, which mediate the entry of coxsackie B viruses and coxsackievirus A21, respectively, functions as a receptor for EV70. EV70 binding to all cell lines was sensitive to sialidase treatment and to inhibition of O glycosylation by benzylN-acetyl-α-d-galactosaminide. Taken together, these results suggest that a sialylated molecule(s) other than DAF serves as a receptor for EV70 on permissive human leukocyte cell lines.
Requirements for CEACAMs and Cholesterol during Murine Coronavirus Cell Entry
Authors: Thorp Edward B. , Gallagher Thomas M.
Published: February 2004

Previous reports have documented that cholesterol supplementations increase cytopathic effects in tissue culture and also intensify in vivo pathogenicities during infection by the enveloped coronavirus murine hepatitis virus (MHV). To move toward a mechanistic understanding of these phenomena, we used growth media enriched with methyl-β-cyclodextrin or cholesterol to reduce or elevate cellular membrane sterols, respectively. Cholesterol depletions reduced plaque development 2- to 20-fold, depending on the infecting MHV strain, while supplementations increased susceptibility 2- to 10-fold. These various cholesterol levels had no effect on the binding of viral spike (S) proteins to cellular carcinoembryonic antigen-related cell adhesion molecule (CEACAM) receptors, rather they correlated directly with S-protein-mediated membrane fusion activities. We considered whether cholesterol was indirectly involved in membrane fusion by condensing CEACAMs into “lipid raft” membrane microdomains, thereby creating opportunities for simultaneous binding of multiple S proteins that subsequently cooperate in the receptor-triggered membrane fusion process. However, the vast majority of CEACAMs were solubilized by cold Triton X-100 (TX-100), indicating their absence from lipid rafts. Furthermore, engineered CEACAMs appended to glycosylphosphatidylinositol anchors partitioned with TX-100-resistant lipid rafts, but cells bearing these raft-associated CEACAMs were not hypersensitive to MHV infection. These findings argued against the importance of cholesterol-dependent CEACAM localizations into membrane microdomains for MHV entry, instead suggesting that cholesterol had a more direct role. Indeed, we found that cholesterol was required even for those rare S-mediated fusions taking place in the absence of CEACAMs. We conclude that cholesterol is an essential membrane fusion cofactor that can act with or without CEACAMs to promote MHV entry.
Interaction and Replication Activation of Genotype I and II Hepatitis Delta Antigens
Authors: Hsu Sheng-Chieh , Wu Jaw-Ching , Sheen I-Jane , Syu Wan-Jr
Published: February 2004

The nucleotide sequences of hepatitis D viruses (HDV) vary 5 to 14% among isolates of the same genotype and 23 to 34% among different genotypes. The only viral-genome-encoded antigen, hepatitis delta antigen (HDAg), has two forms that differ in size. The small HDAg (HDAg-S)
trans
-activates viral replication, while the large form (HDAg-L) is essential for viral assembly. Previously, it has been shown that the packaging efficiency of HDAg-L is higher for genotype I than for genotype II. In this study, the question of whether other functional properties of the HDAgs are affected by genotype differences is addressed. By coexpression of the two antigens in HuH-7 cells followed by specific antibody precipitation, it was found that HDAgs of different origins interacted without genotypic discrimination. Moreover, in the presence of hepatitis B virus surface antigen, HDAg-S was incorporated into virion-like particles through interaction with HDAg-L without genotype restriction. As to the differences in replication activation of genotype I HDV RNA, all HDAg-S clones tested had some
trans
-activation activity, and this activity varied greatly among isolates. As to the support of HDV genotype II replication, only clones of HDAg-S from genotype II showed
trans
-activation activity, and this activity also varied among isolates. In conclusion, genotype has no effect on HDAg interaction and genotype per se only partly predicts how much the HDAg-S of an HDV isolate affects the replication of a second HDV isolate.
Presence of an Encephalomyocarditis Virus Internal Ribosome Entry Site Sequence in Avian Infectious Bronchitis Virus Defective RNAs Abolishes Rescue by Helper Virus
Authors: Dove Brian , Cavanagh David , Britton Paul
Published: February 2004

Avian infectious bronchitis virus (IBV) defective RNAs (D-RNAs) have been used for the expression of heterologous genes in a helper-virus-dependent expression system. The heterologous genes were expressed under the control of an IBV transcription-associated sequence (TAS) derived from gene 5 of IBV Beaudette. However, coronavirus D-RNA expression vectors display an inherent instability following serial passage with helper virus, resulting in the eventual loss of the heterologous genes. The use of the picornavirus encephalomyocarditis virus (EMCV) internal ribosome entry site (IRES) sequence to initiate gene translation was investigated as an alternative method to the coronavirus-mediated TAS-controlled heterologous gene expression system. IBV D-RNAs containing the chloramphenicol acetyltransferase (CAT) reporter gene, under EMCV IRES control, were assessed for IRES-mediated CAT protein translation. CAT protein was detected from T7-derived IBV D-RNA transcripts in a cell-free protein synthesis system and in situ in avian chick kidney (CK) cells following T7-derived D-RNA synthesis from a recombinant fowlpox virus expressing the bacteriophage T7 DNA-dependent RNA polymerase. However, CAT protein was not detected in CK cells from IRES-containing IBV D-RNAs, in which the IRES-CAT construct was inserted at two different positions within the D-RNA, in the presence of helper IBV. Northern blot analysis demonstrated that the IRES-containing D-RNAs were not rescued on serial passage with helper virus, indicating that the EMCV IRES sequence had a detrimental effect on IBV D-RNA rescue.
In Vivo Evolution of X4 Human Immunodeficiency Virus Type 1 Variants in the Natural Course of Infection Coincides with Decreasing Sensitivity to CXCR4 Antagonists
Authors: Stalmeijer Evelien H. B. , van Rij Ronald P. , Boeser-Nunnink Brigitte , Visser Janny A. , Naarding Marloes A. , Schols Dominique , Schuitemaker Hanneke
Published: February 2004

CXCR4-using (X4) human immunodeficiency virus type 1 (HIV-1) variants evolve from CCR5-restricted (R5) HIV-1 variants. Early after their first appearance in vivo, X4 HIV-1 variants additionally use CCR5. The ability to use CCR5 in addition to CXCR4 is generally lost late in infection. Here we studied whether this evolution of the coreceptor repertoire is also reflected in a changing sensitivity of X4 variants to CXCR4 antagonists such as peptide T22 and the synthetic compound AMD3100. We observed differences in the concentrations of CXCR4 antagonists needed to suppress replication of X4 HIV variants from different patients. In general, late X4 HIV variants were less sensitive to AMD3100 than were early R5X4 HIV variants. The differences between early R5X4 HIV variants and late X4 variants were less pronounced for T22-mediated inhibition. These results suggest an ongoing evolution of X4 virus variants toward more efficient usage of the cellular entry complex.
Effect of Interaction between Hepatitis C Virus NS5A and NS5B on Hepatitis C Virus RNA Replication with the Hepatitis C Virus Replicon
Authors: Shimakami Tetsuro , Hijikata Makoto , Luo Hong , Ma Yuan Yuan , Kaneko Shuichi , Shimotohno Kunitada , Murakami Seishi
Published: February 2004

Hepatitis C virus (HCV) NS5A has been reported to be important for the establishment of replication by adaptive mutations or localization, although its role in viral replication remains unclear. It was previously reported that NS5A interacts with NS5B via two regions of NS5A in the isolate JK-1 and modulates the activity of NS5B RdRp (Y. Shirota et al., J. Biol. Chem.,
277:
11149-11155, 2002), but the biological significance of this interaction has not been determined. In this study, we addressed the effect of this interaction on HCV RNA replication with an HCV replicon system derived from the isolate M1LE (H. Kishine et al., Biochem. Biophys. Res. Commun.,
293:
993-999, 2002). We constructed three internal deletion mutants, M1LE/5Adel-1 and M1LE/5Adel-2, each encoding NS5A which cannot bind NS5B, and M1LE/5Adel-3, encoding NS5A that can bind NS5B. After transfection into Huh-7 cells, M1LE/5Adel-3 was replication competent, but both M1LE/5Adel-1 and M1LE/5Adel-2 were not. Next we prepared 20 alanine-substituted clustered mutants within both NS5B-binding regions and examined the effect of these mutants on HCV RNA replication. Only 5 of the 20 mutants were replication competent. Subsequently, we introduced a point mutation, S225P, a deletion of S229, or S232I into NS5A and prepared cured Huh-7 cells that were cured of RNA replication by alpha interferon. Finally, with these point mutations and cured cells, we established a highly improved replicon system. In this system, only the same five mutants were replication competent. These results strongly suggest that the interaction between NS5A and NS5B is critical for HCV RNA replication in the HCV replicon system.
Cul7/p185/p193 Binding to Simian Virus 40 Large T Antigen Has a Role in Cellular Transformation
Authors: Ali Syed Hamid , Kasper Jocelyn S. , Arai Takehiro , DeCaprio James A.
Published: February 2004

Simian virus 40 large T antigen (TAg) is a viral oncoprotein that can promote cellular transformation. TAg's transforming activity results in part by binding and inactivating key tumor suppressors, including p53 and the retinoblastoma protein (pRb). We have identified a TAg-associated 185-kDa protein that has significant homology to the cullin family of E3 ubiquitin ligases. TAg binds to an SCF-like complex that contains p185/Cul7, Rbx1, and the F box protein Fbw6. This SCF-like complex binds to an N-terminal region of TAg. Several p185/Cul7-binding-deficient mutants of TAg were generated that retained binding to pRb and p53 and were capable of overcoming Rb-mediated repression of E2F transcription. Despite binding to pRb and p53, these p185/Cul7-binding-defective mutants of TAg were unable to transform primary mouse embryo fibroblasts. Cells expressing p185/Cul7-binding-defective mutants of TAg were unable to grow to high density or grow in an anchorage-independent manner as determined by growth in soft agar. Considering the significance of other TAg-interacting proteins in regulation of the cell cycle, p185/Cul7 may also regulate an important growth control pathway.
Interaction between a Geminivirus Replication Protein and the Plant Sumoylation System
Authors: Castillo A. G. , Kong L. J. , Hanley-Bowdoin L. , Bejarano E. R.
Published: February 2004

Geminiviruses are small DNA viruses that replicate in nuclei of infected plant cells after accumulation of host replication machinery.
Tomato golden mosaic virus
(TGMV) and
Tomato yellow leaf curl Sardinia virus
(TYLCSV) encode a protein, RepAC1 (or Rep), that is essential for viral replication. Rep/RepAC1 is an oligomeric protein that binds to double-stranded DNA, catalyzes cleavage and ligation of single-stranded DNA, and is sufficient for host induction. It also interacts with several host proteins, including the cell cycle regulator, retinoblastoma, and essential components of the cell DNA replication machinery, like proliferating nuclear cell antigen (PCNA) and RFC-1. To identify other cellular proteins that interact with Rep/RepAC1 protein, a
Nicotiana benthamiana
cDNA library was screened with a yeast two-hybrid assay. The host cell sumoylation enzyme, NbSCE1 (
N. benthamiana
SUMO-conjugating enzyme, homolog to
Saccharomyces cerevisiae
UBC9), was found to interact specifically with RepAC1. Mapping studies localized the interaction to the N-terminal half of RepAC1. Effects on geminivirus replication were observed in transgenic plants with altered levels of SUMO, the substrate for UBC9.
Induction of Potent Humoral and Cell-Mediated Immune Responses by Attenuated Vaccinia Virus Vectors with Deleted Serpin Genes
Authors: Legrand Fatema A. , Verardi Paulo H. , Jones Leslie A. , Chan Kenneth S. , Peng Yue , Yilma Tilahun D.
Published: February 2004

Vaccinia virus (VV) has been effectively utilized as a live vaccine against smallpox as well as a vector for vaccine development and immunotherapy. Increasingly there is a need for a new generation of highly attenuated and efficacious VV vaccines, especially in light of the AIDS pandemic and the threat of global bioterrorism. We therefore developed recombinant VV (rVV) vaccines that are significantly attenuated and yet elicit potent humoral and cell-mediated immune responses. B13R (SPI-2) and B22R (SPI-1) are two VV immunomodulating genes with sequence homology to serine protease inhibitors (serpins) that possess antiapoptotic and anti-inflammatory properties. We constructed and characterized rVVs that have the B13R or B22R gene insertionally inactivated (vΔB13R and vΔB22R) and coexpress the vesicular stomatitis virus glycoprotein (v50ΔB13R and v50ΔB22R). Virulence studies with immunocompromised BALB/cBy nude mice indicated that B13R or B22R gene deletion decreases viral replication and significantly extends time of survival. Viral pathogenesis studies in immunocompetent CB6F1mice further demonstrated that B13R or B22R gene inactivation diminishes VV virulence, as measured by decreased levels of weight loss and limited viral spread. Finally, rVVs with B13R and B22R deleted elicited potent humoral, T-helper, and cytotoxic T-cell immune responses, revealing that the observed attenuation did not reduce immunogenicity. Therefore, inactivation of immunomodulating genes such as B13R or B22R represents a general method for enhancing the safety of rVV vaccines while maintaining a high level of immunogenicity. Such rVVs could serve as effective vectors for vaccine development and immunotherapy.
Frequent Simian Foamy Virus Infection in Persons Occupationally Exposed to Nonhuman Primates
Authors: Switzer William M. , Bhullar Vinod , Shanmugam Vedapuri , Cong Mian-er , Parekh Bharat , Lerche Nicholas W. , Yee JoAnn L. , Ely John J. , Boneva Roumiana , Chapman Louisa E. , Folks Thomas M. , Heneine Walid
Published: February 2004

The recognition that AIDS originated as a zoonosis heightens public health concerns associated with human infection by simian retroviruses endemic in nonhuman primates (NHPs). These retroviruses include simian immunodeficiency virus (SIV), simian T-cell lymphotropic virus (STLV), simian type D retrovirus (SRV), and simian foamy virus (SFV). Although occasional infection with SIV, SRV, or SFV in persons occupationally exposed to NHPs has been reported, the characteristics and significance of these zoonotic infections are not fully defined. Surveillance for simian retroviruses at three research centers and two zoos identified no SIV, SRV, or STLV infection in 187 participants. However, 10 of 187 persons (5.3%) tested positive for SFV antibodies by Western blot (WB) analysis. Eight of the 10 were males, and 3 of the 10 worked at zoos. SFV integrase gene (
int
) and
gag
sequences were PCR amplified from the peripheral blood lymphocytes available from 9 of the 10 persons. Phylogenetic analysis showed SFV infection originating from chimpanzees (
n
= 8) and baboons (
n
= 1). SFV seropositivity for periods of 8 to 26 years (median, 22 years) was documented for six workers for whom archived serum samples were available, demonstrating long-standing SFV infection. All 10 persons reported general good health, and secondary transmission of SFV was not observed in three wives available for WB and PCR testing. Additional phylogenetic analysis of
int
and
gag
sequences provided the first direct evidence identifying the source chimpanzees of the SFV infection in two workers. This study documents more frequent infection with SFV than with other simian retroviruses in persons working with NHPs and provides important information on the natural history and species origin of these infections. Our data highlight the importance of studies to better define the public health implications of zoonotic SFV infections.
Genetic and Phenotypic Analyses of Human Immunodeficiency Virus Type 1 Escape from a Small-Molecule CCR5 Inhibitor
Authors: Kuhmann Shawn E. , Pugach Pavel , Kunstman Kevin J. , Taylor Joann , Stanfield Robyn L. , Snyder Amy , Strizki Julie M. , Riley Janice , Baroudy Bahige M. , Wilson Ian A. , Korber Bette T. , Wolinsky Steven M. , Moore John P.
Published: February 2004

We have described previously the generation of an escape variant of human immunodeficiency virus type 1 (HIV-1), under the selection pressure of AD101, a small molecule inhibitor that binds the CCR5 coreceptor (A. Trkola, S. E. Kuhmann, J. M. Strizki, E. Maxwell, T. Ketas, T. Morgan, P. Pugach, S. X. L. Wojcik, J. Tagat, A. Palani, S. Shapiro, J. W. Clader, S. McCombie, G. R. Reyes, B. M. Baroudy, and J. P. Moore, Proc. Natl. Acad. Sci. USA 99:395-400, 2002). The escape mutant, CC101.19, continued to use CCR5 for entry, but it was at least 20,000-fold more resistant to AD101 than the parental virus, CC1/85. We have now cloned theenvgenes from the the parental and escape mutant isolates and made chimeric infectious molecular clones that fully recapitulate the phenotypes of the corresponding isolates. Sequence analysis of the evolution of the escape mutants suggested that the most relevant changes were likely to be in the V3 loop of the gp120 glycoprotein. We therefore made a series of mutant viruses and found that full AD101 resistance was conferred by four amino acid changes in V3. Each change individually caused partial resistance when they were introduced into the V3 loop of a CC1/85 clone, but their impact was dependent on the gp120 context in which they were made. We assume that these amino acid changes alter how the HIV-1 Env complex interacts with CCR5. Perhaps unexpectedly, given the complete dependence of the escape mutant on CCR5 for entry, monomeric gp120 proteins expressed from clones of the fully resistant isolate failed to bind to CCR5 on the surface of L1.2-CCR5 cells under conditions where gp120 proteins from the parental virus and a partially AD101-resistant virus bound strongly. Hence, the full impact of the V3 substitutions may only be apparent at the level of the native Env complex.
Structural and Functional Properties of an Unusual Internal Fusion Peptide in a Nonenveloped Virus Membrane Fusion Protein
Authors: Shmulevitz Maya , Epand Raquel F. , Epand Richard M. , Duncan Roy
Published: February 2004

The avian and Nelson Bay reoviruses are two of only a limited number of nonenveloped viruses capable of inducing cell-cell membrane fusion. These viruses encode the smallest known membrane fusion proteins (p10). We now show that a region of moderate hydrophobicity we call the hydrophobic patch (HP), present in the small N-terminal ectodomain of p10, shares the following characteristics with the fusion peptides of enveloped virus fusion proteins: (i) an abundance of glycine and alanine residues, (ii) a potential amphipathic secondary structure, (iii) membrane-seeking characteristics that correspond to the degree of hydrophobicity, and (iv) the ability to induce lipid mixing in a liposome fusion assay. The p10 HP is therefore predicted to provide a function in the mechanism of membrane fusion similar to those of the fusion peptides of enveloped virus fusion peptides, namely, association with and destabilization of opposing lipid bilayers. Mutational and biophysical analysis suggested that the internal fusion peptide of p10 lacks alpha-helical content and exists as a disulfide-stabilized loop structure. Similar kinked structures have been reported in the fusion peptides of several enveloped virus fusion proteins. The preservation of a predicted loop structure in the fusion peptide of this unusual nonenveloped virus membrane fusion protein supports an imperative role for a kinked fusion peptide motif in biological membrane fusion.
Retinoid-Dependent Restriction of Human Immunodeficiency Virus Type 1 Replication in Monocytes/Macrophages
Authors: Hanley Timothy M. , Kiefer Heather L. B. , Schnitzler Aletta C. , Marcello Jennifer E. , Viglianti Gregory A.
Published: February 2004

Vitamin A deficiency has been correlated with increased severity of human immunodeficiency virus type 1 (HIV-1)-associated disease. Moreover, vitamin A supplementation can reduce AIDS-associated morbidity and mortality. Our group and others have shown that retinoids, the bioactive metabolites of vitamin A, repress HIV-1 replication in monocytic cell lines and primary macrophages by blocking long-terminal-repeat (LTR)-directed transcription. Based on these studies, we hypothesize that retinoids are natural repressors of HIV-1 in vivo. We show here that all-trans-retinoic acid (RA)-mediated repression of HIV-1 activation requires pretreatment for at least 12 h and is blocked by the protein synthesis inhibitors cycloheximide and puromycin. Studies of the kinetics of RA-mediated repression in U1 cells and primary monocyte-derived macrophages (MDMs) reveal that the repressive effects of RA on HIV-1 expression are long-lasting but reversible. We demonstrate that HIV-1 expression is activated when U1 cells or MDMs are cultured in retinoid-free synthetic medium and show that physiological concentrations of RA repress this activation. In addition, the synthetic pan-retinoic acid receptor antagonist BMS-204 493 activates HIV-1 replication in U1 cells in a dose-dependent manner, suggesting that RA-induced transactivation of cellular gene expression is required for HIV-1 repression. Together, these data support the hypothesis that retinoids present in tissue culture media in vitro and serum in vivo maintain HIV-1 in a transcriptionally repressed state in monocytes/macrophages.