bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of religious observance on infants’ sleep position in the Jewish population
Authors: Sivan Y , Reisner S , Amitai Y , Wasser J , Nehama H , Tauman R
Published: September 2004

Objectives:  To describe the effect of the level of religiousness on infants’ sleep position in the Jewish population.

Methods:  A longitudinal telephone survey of randomly selected 608 2‐month‐old Jewish infants repeated at 4 and 6 months. Results were analyzed versus the four levels of Jewish religion observance.

Results:  A significant correlation was found between the level of religious practice and sleep position (P ≤ 0.002). 56.8% (50/88) of ultra‐orthodox parents put their babies to sleep in the non‐prone position, compared with 79% (411/520) in the other three groups (P < 0.001). Non‐prone sleeping decreased when infants grew. Higher parity correlated with the level of religiousness and with prone sleeping in religious families (OR = 1.15, 95% CI 1.00−1.33, P < 0.001).

Conclusions:  Jews and especially the ultra‐orthodox families comply significantly less with recommendations to avoid prone sleeping. Specific measures may be required in this population that rely more on personal experience and belief than on health care provider advice.
Use of intranasal midazolam to treat acute seizures in paediatric community settings
Authors: Harbord MG , Kyrkou NE , Kyrkou MR , Kay D , Coulthard KP
Published: September 2004

Objectives:  To evaluate the acceptability of intranasal midazolam (INM) in acute seizure management in the community.

Methods:  Parents and staff in residential and educational settings were trained in first aid and seizure management and the administration of INM. Feedback was obtained from those who had given INM over the 30‐month period September 2000−March 2003.

Results:  Intranasal midazolam was administered to 22 children for a total of 54 seizures (range 1−6 seizures each). The dose was 0.2−0.3 mg/kg rounded down to 1 or 2 of the 5 mg in 1‐mL plastic ampoules, with the anticonvulsant instilled into the child's nose directly from the plastic ampoule. Seizures were effectively stopped on 48 occasions, i.e. 89%, while no respiratory arrests occurred. Thirty carers had given INM to a convulsing child and 27 (90%) reported no difficulty in administering it. Fifteen people had also previously administered rectal diazepam and INM was considered easier to administer than rectal diazepam by 13 while a preference to use INM rather than rectal diazepam was indicated by 14.

Conclusion:  This study has shown that INM is an acceptable treatment option as a first aid response for acute seizures. We believe that INM should be considered as the preferred alternative in the community setting, as it is easier to administer and is more dignified for the patient than rectal diazepam.
Transverse myelitis after measles and rubella vaccination
Authors: Lim S , Park SM , Choi HS , Kim DK , Kim HB , Yang BG , Lee JK
Published: September 2004

Abstract:  The incidence of severe neurological complications associated with measles or rubella vaccination is low. A 9‐year‐old girl developed urinary retention and lower limb paralysis 16 days after measles and rubella vaccination. Her illness was diagnosed as transverse myelitis. Clinical, laboratory and magnetic resonance image findings were consistent with her diagnosis. She was treated with steroids and discharged with only mild lower limb weakness.
Follow the Thing: Papaya
Authors: Cook Ian
Published: September 2004

In a recent round table about Antipode's radical geographies, contributors argued that the journal needed more papers which stimulated debate, were accessible to academics and non‐academics alike, didn’t “preach to the cognoscenti”, were written to fit into radical teaching agendas, and were diverse and eclectic in style (Waterstone 2002:663; Hague 2002). This paper has been written to fit this bill. It outlines the findings of multi‐locale ethnographic research into the globalization of food, focusing on a supply chain stretching from UK supermarket shelves to a Jamaican farm, and concluding in a North London flat. It addresses perspectives and critiques from the growing literature on the geographies of commodities, but presents these academic arguments “between the lines” of a series of overlapping vignettes about people who were (un)knowingly connected to each other through the international trade in fresh papaya, and an entangled range of economic, political, social, cultural, agricultural and other processes also shaping these connections in the early 1990s. The research on which it is based was initially energized by David Harvey's (1990:422) call for radical geographers to “get behind the veil, the fetishism of the market”, to make powerful, important, disturbing connections between Western consumers and the distant strangers whose contributions to their lives were invisible, unnoticed, and largely unappreciated. Harvey argued that radical geographers should attempt to de‐fetishise commodities, re‐connect consumers and producers, tell fuller stories of social reproduction, and thereby provoke moral and ethical questions for participants in this exploitation who might think they’re decent people. This paper has been written to provoke such questions, to provide materials to think through and with, for geography's ongoing debates about the politics of consumption.
Revenge and Injustice in the Neoliberal City: Uncovering Masculinist Agendas
Authors: Hubbard Phil
Published: September 2004

The literature on the Western city as a site of “actually existing neoliberalism” has done much to expose the injustices wrought by new modes of urban governance. In particular, this literature has highlighted the increasing exclusion of minority groups from the spaces of the central city. To date, however, there has been little sustained exploration of the gendered dimensions of this process. In this paper I offer such a gendered reading, suggesting that neoliberal policy serves to recentre masculinity in the cityscape at the same time that it encourages capital accumulation. I demonstrate this by noting some of the forms of revenge currently being exacted on prostitute women in Western cities, reading such actions as symptomatic of urban policies that serve both capital and the phallus. In conclusion, I suggest that the conceptual framework of neoliberalism is useful for making sense of contemporary urban restructuring, but only if we recognise that the resulting city can be mapped along axes other than those fixated on capital and class.
The Nature of Things: Dead Labor, Nonhuman Actors, and the Persistence of Marxism
Authors: Kirsch Scott , Mitchell Don
Published: September 2004

This article is about the question of social agency in the animation of things, and about how this problematic has been conceptualized in Marxist and Actor‐Network Theory (ANT) approaches to human–nature–technology relations. Notwithstanding many obvious differences, we note that each tradition was founded on a radical shift to a relational ontology, a world of relations and processes and not things‐in‐themselves, and that each has developed, partly as a consequence of this move, analytically useful ways of investigating and talking about the work that things do, or appear to do, in the world. By relating the ANT category of non‐human actors to the Marxist concept of dead labor, and by revisiting Marx's own dialectics of technology as embodied in his figure of the “living machine” in Capital, we explore the different implications of these approaches for our understandings of the nature, materiality, and the efficacy of social agents. We argue that ANT's reconfiguration of agency as a collective social and technical process—a process wherein the “nonhuman” can have very real social effects—can be deepened and given some political efficacy only if we take seriously the ontological problems of causality, accountability, and the directedness of social relations (and things) which ANT, and its wider, still evolving ethos among the social sciences and cultural studies, would have us forestall.
Entry in a Dynamic Model with Equilibrium Price Dispersion with an Application to the Market for Long‐Distance Telephone Services
Authors: Nayyar Ashish
Published: September 2004

Models of entry based on the traditional models of oligopoly do not allow for price dispersions on homogenous products. Yet, such price dispersions do exist for homogenous products, and a firm does not lose its entire market share when it fails to charge the lowest price. Existing models of equilibrium price dispersion are not designed to analyze entry in a dynamic framework. A dynamic model is developed that allows an analysis of the effects of entry into a previously monopolized market. Despite asymmetric initial shares, the market shares of equally efficient firms tend to equalize over time. An application is the market for long‐distance telephone services following the divestiture of the bell operating companies from AT&T.
The impact of tax‐financed pensions on poverty reduction in Latin America: Evidence from Argentina, Brazil, Chile, Costa Rica and Uruguay
Authors: Bertranou Fabio M. , Van Ginneken Wouter , Solorio Carmen
Published: September 2004

In many Latin American countries, tax‐financed pensions (TFPs) have expanded, mainly resulting from growing informalization of employment and stagnating or declining pension insurance coverage. In the five countries examined in this article, TFPs have generally been effective in reducing poverty and indigence. In Brazil rural social assistance pensions cut the incidence of destitution among poor older people by 95 per cent. In Chile TFPs considerably improved their poverty reduction effectiveness between 1990 and 2000. Tax‐financed pensions have therefore been seen as an instrument to supplement contributory pension coverage and boost overall social security coverage. A key challenge is to increase pension insurance coverage through existing statutory pension insurance or special contributory schemes targeted on workers in the informal economy. Otherwise, TFPs could become financially and socially unsustainable in the future. There are also various ways to improve the financing, administration and eligibility criteria of TFPs, particularly because it is necessary to define consistent structure and benefit policies between these and contributory schemes.
Healthcare funding problems in Algeria
Authors: Tlilane Nouara Kaïd
Published: September 2004

During the 1990s, a period of economic crisis, the health sector was involved in Algeria's broader transition to a market economy and the start of the process of privatization, with the result that the general level of health was affected by the structural adjustment policy pursued. Financing healthcare is an extremely serious problem. Seen as the primary source of difficulties in the national health system, it has become a major concern for both the authorities and the general public. Because of the difficulties, the healthcare needs of the population cannot be met, even though state, social security and household spending are constantly on the increase. This article attempts to analyse the funding mechanisms and the level of healthcare expenditure in Algeria.
Sunshine is good medicine. The health benefits of ultraviolet‐B induced vitamin D production
Authors: Grant W B , Strange R C , Garland C F
Published: September 2004

Most public health statements regarding exposure to solar ultraviolet radiation (UVR) recommend avoiding it, especially at midday, and using sunscreen. Excess UVR is a primary risk factor for skin cancers, premature photoageing and the development of cataracts. In addition, some people are especially sensitive to UVR, sometimes due to concomitant illness or drug therapy.

However, if applied uncritically, these guidelines may actually cause more harm than good. Humans derive most of their serum 25‐hydroxycholecalciferol (25(OH)D3) from solar UVB radiation (280–315 nm). Serum 25(OH)D3 metabolite levels are often inadequate for optimal health in many populations, especially those with darker skin pigmentation, those living at high latitudes, those living largely indoors and in urban areas, and during winter in all but the sunniest climates. In the absence of adequate solar UVB exposure or artificial UVB, vitamin D can be obtained from dietary sources or supplements.

There is compelling evidence that low vitamin D levels lead to increased risk of developing rickets, osteoporosis and osteomaloma, 16 cancers (including cancers of breast, ovary, prostate and non‐Hodgkin's lymphoma), and other chronic diseases such as psoriasis, diabetes mellitus, hypertension, heart disease, myopathy, multiple sclerosis, schizophrenia, hyperparathyroidism and susceptibility to tuberculosis.

The health benefits of UVB seem to outweigh the adverse effects. The risks can be minimized by avoiding sunburn, excess UVR exposure and by attention to dietary factors, such as antioxidants and limiting energy and fat consumption. It is anticipated that increasing attention will be paid to the benefits of UVB radiation and vitamin D and that health guidelines will be revised in the near future.
The treatment of leg telangiectasia
Authors: Neumann H A M , Kockaert M A
Published: September 2004

Leg telangiectasia is more difficult to treat than facial telangiectasia. Investigations may be needed to elucidate the origin of the telangiectasia. In cases of venous insufficiency, investigation of venous haemodynamics is desirable. Treatment is primarily by sclerotherapy, including foam sclerotherapy. Light and laser treatments are also effective, especially for telangiectasia up to 1 mm in diameter. New developments incorporate longer pulse durations, such as frequency‐doubled neodynium YAG and diode lasers as well as intense pulsed light. After all treatment methods, compression for 48 h using pads, bandages or hosiery is recommended. As with all cosmetic procedures, patients need to be tutored comprehensively about anticipated results and possible complications or side‐effects.
Patient satisfaction with laser hair removal
Authors: Preston P W , Lanigan S W
Published: September 2004

Background  Laser hair removal (LHR) is a widely used treatment for unwanted hair.

Aim  To determine patient satisfaction with LHR.

Methods  The clinic offered LHR by long pulse ruby, alexandrite and Nd:YAG. Patients attending the LHR clinic completed a patient satisfaction questionnaire. Satisfaction with LHR treatment was recorded on a linear analogue scale (LAS 0 = laser very much worse than alternative method; 10 = laser very much better than the alternative method).

Results  In terms of hair removal, 71% of patients were satisfied with their treatment. Laser treatment compared favourably with electrolysis and waxing. LHR scored 8.6 when compared with electrolysis and 7.7 when compared with waxing. During LHR treatments, 61% of patients used fewer ancillary methods than before. Most patients would recommend LHR to other persons with unwanted hair.

Conclusions  Most patients were satisfied with LHR.
The Haunted Physics Lab
Authors: Zepf Thomas H.
Published: September 2004

During the Halloween season at Creighton University, our students and the public are treated to a haunted physics laboratory. Visitors to the lab learn physics while having fun as they are confronted with a maze of exhibits that demonstrate optical, electrical, and mechanical phenomena in the context of Halloween.
Tossing on a Rotating Space Station
Authors: Paetkau Mark
Published: September 2004

The following analysis was inspired by a question posed by a listener of a radio science show.1 The listener asked the question: “If an astronaut in a space station that was rotating to simulate gravity threw a ball up, where would the ball go?” The physicist answered, “The ball would travel straight across the space station (assuming an open structure). “The main point is that to an outside observer the ball would not “fall” back down as on Earth. As I pondered this it occurred to me that while the answer is correct, it is a special case with a more general solution. Below is an analysis of the motions a thrown object can undergo on a rotating space station. The first part of the discussion is aimed at lower-level undergraduates who have a basic understanding of vectors and circular motion, and the motion is described from the point of view of an external reference frame. Further analysis of the motion by an observer on the space station is appropriate for upper-level students.
Assessing-To-Learn: Formative Assessment in Physics Instruction
Authors: Dufresne Robert J. , Gerace William J.
Published: September 2004

Assessment designed to enhance teaching and learning is called “formative assessment.” During formative assessment, teachers and students seek information about the state of student learning and then use the acquired information to adapt teaching and learning to meet student needs. “Classroom formative assessment” (CFA) requires that teachers explicitly engage in formative assessment during classroom learning activities. At a basic level, CFA occurs naturally and is a common part of most instructional settings. Nevertheless, the systematic practice of CFA is rare in secondary and post-secondary science education. Here we provide suggestions for those interested in formative assessment for use in teaching introductory physics. A simple model of classroom formative assessment is presented. Included are examples of formative assessment activities and suggestions for implementation.
Question Their Answers
Authors: Royce Brenda
Published: September 2004

Brenda Royce has been teaching high school chemistry and physics for nine years, and is currently science department chair at University High School in Fresno, CA, a college prep charter school on the CSU Fresno campus. She also enjoys coaching Science Olympiad, and working with science and math student teachers as a workshop leader and mentor teacher through the Science and Math Education Center at CSUF. Prior to teaching, she worked in analytical and environmental chemistry for several years. Brenda shares with us her strategy of answering students' questions by “questioning their answers.”
Human Cytomegalovirus TRS1 Protein Is Required for Efficient Assembly of DNA-Containing Capsids
Authors: Adamo Joan E. , Schröer Jörg , Shenk Thomas
Published: September 2004

The human cytomegalovirus tegument protein, pTRS1, appears to function at several discrete stages of the virus replication cycle. We previously demonstrated that pTRS1 acts during the late phase of infection to facilitate the production of infectious virions. We now have more precisely identified the late pTRS1 function by further study of a mutant virus lacking the TRS1 region, AD
sub
TRS1. We observed a significant reduction in the production of capsids, especially DNA-containing C-capsids, in mutant virus-infected cells. AD
sub
TRS1 exhibited normal cleavage of DNA concatemers, so the defect in C-capsid production must occur after DNA cleavage and before DNA is stably inserted into a capsid. Further, the normal virus-induced morphological reorganization of the nucleus did not occur after infection with the pTRS1-deficient mutant.
Vaccinia Virus Mutants with Alanine Substitutions in the Conserved G5R Gene Fail To Initiate Morphogenesis at the Nonpermissive Temperature
Authors: da Fonseca Flavio G. , Weisberg Andrea S. , Caeiro Maria F. , Moss Bernard
Published: September 2004

The initial characterization of the product of the vaccinia virus G5R gene, which is conserved in all poxviruses sequenced to date, is described. The G5 protein was detected in the core fraction of purified virions, and transcription and translation of the G5R open reading frame occurred early in infection, independently of DNA replication. Attempts to delete the G5R gene and isolate a replication-competent virus were unsuccessful, suggesting that G5R encodes an essential function. We engineered vaccinia virus mutants with clusters of charged amino acids changed to alanines and determined that several were unable to replicate at 40°C but grew well at 37°C. At the nonpermissive temperature, viral gene expression and DNA replication and processing were unperturbed. However, tyrosine phosphorylation and proteolytic cleavage of the A17 membrane protein and proteolytic cleavage of core proteins were inhibited at 40°C, suggesting an assembly defect. The cytoplasm of cells that had been infected at the nonpermissive temperature contained large granular areas devoid of cellular organelles or virus structures except for occasional short crescent-shaped membranes and electron-dense lacy structures. The temperature-sensitive phenotype of the G5R mutants closely resembled the phenotypes of vaccinia virus mutants carrying conditionally lethal F10R protein kinase and H5R mutations. F10, although required for phosphorylation of A17 and viral membrane formation, was synthesized by the G5R mutants under nonpermissive conditions. An intriguing possibility is that G5 participates in the formation of viral membranes, a poorly understood event in poxvirus assembly.
Human Immunodeficiency Virus Type 1 Gag-Specific Mucosal Immunity after Oral Immunization with Papillomavirus Pseudoviruses Encoding Gag
Authors: Zhang Hongtao , Fayad Raja , Wang Xilin , Quinn Daniel , Qiao Liang
Published: September 2004

Mucosal surfaces are the primary portals for human immunodeficiency virus (HIV) transmission. Because systemic immunization, in general, does not induce effective mucosal immune responses, a mucosal HIV vaccine is urgently needed. For this study, we developed papillomavirus pseudoviruses that express HIV-1 Gag. The pseudoviruses are synthetic, nonreplicating viruses, yet they can produce antigens for a long time in the immune system. Here we show that oral immunization of mice by the use of papillomavirus pseudoviruses encoding Gag generated mucosal and systemic Gag-specific cytotoxic T lymphocytes that effectively lysed Gag-expressing target cells. Furthermore, the pseudoviruses generated Gag-specific gamma interferon-producing T cells and serum immunoglobulin G (IgG) and mucosal IgA. In contrast, oral immunization with plasmid DNA encoding HIV-1 Gag did not induce specific immune responses. Importantly, oral immunization with the pseudoviruses induced Gag-specific memory cytotoxic T lymphocytes and protected mice against a rectal mucosal challenge with a recombinant vaccinia virus expressing HIV-1 Gag. Thus, papillomavirus pseudoviruses encoding Gag are a promising mucosal vaccine against AIDS.
Amsacta mooreiEntomopoxvirus Expresses an Active Superoxide Dismutase
Authors: Becker M. N. , Greenleaf W. B. , Ostrov D. A. , Moyer R. W.
Published: September 2004

The entomopoxvirus fromAmsacta mooreiserves as the prototype of the group B entomopoxviruses. One of the interesting genes found inAmsacta mooreientomopoxvirus (AmEPV) is a superoxide dismutase (sod) (open reading frame AMV255). Superoxide dismutases (SODs) catalyze the conversion of superoxide radicals to hydrogen peroxide and oxygen. Many vertebrate poxviruses contain asodgene, but to date, none have been demonstrated to be active. There are three families of SODs, characterized by their metal ion-binding partners, Fe, Mn, or Cu and Zn. Poxvirus enzymes belong to the Cu-Zn SOD family. Unlike inactive vertebrate poxvirus SODs, AMVSOD contains all the amino acids necessary for function. We expressed and purified a 6X-His-tagged version of the AMVSOD inEscherichia coli. The recombinant AMVSOD demonstrates superoxide dismutase activity both in an in situ gel assay and by stopped flow spectrophotometry. Thekcat/Kmfor AMVSOD is 4 × 107M−1s−1. In infected cells, the AMVSOD protein behaves as a dimer and is catalytically active; however, disruption of the gene in AMEPV has little or no effect on growth of the virus in cell culture. An analysis of mRNA expression indicates that AMVsodis expressed late during infection ofLymantria dispar(Ld652) cells and produces a discrete nonpolydisperse transcript. Characterization of protein expression with a monoclonal antibody generated against AMVSOD confirms that the AMVSOD protein can be classified as a late, postreplicative gene. Therefore, AMVSOD is the first example of an active poxvirus SOD.
In Vivo Function of a Gammaherpesvirus Virion Glycoprotein: Influence on B-Cell Infection and Mononucleosis
Authors: Stewart James P. , Silvia Ondine J. , Atkin Isobel M. D. , Hughes David J. , Ebrahimi Bahram , Adler Heiko
Published: September 2004

The human gammaherpesviruses Epstein-Barr virus and Kaposi Sarcoma-associated herpesvirus both contain a glycoprotein (gp350/220 and K8.1, respectively) that mediates binding to target cells and has been studied in great detail in vitro. However, there is no direct information on the role that these glycoproteins play in pathogenesis in vivo. Infection of mice by murid herpesvirus 4 strain 68 (MHV-68) is an established animal model for gammaherpesvirus pathogenesis and expresses an analogous glycoprotein, gp150. To elucidate the in vivo function of gp150, a recombinant MHV-68 deficient in gp150 production was generated (vgp150Δ). The productive viral replication in vitro and in vivo was largely unaffected by mutation of gp150, aside from a partial defect in the release of extracellular virus. Likewise, B-cell latency was established. However, the transient mononucleosis and spike in latently infected cells associated with the spread of MHV-68 to the spleen was significantly reduced in vgp150Δ-infected mice. A soluble, recombinant gp150 was found to bind specifically to B cells but not to epithelial cells in culture. In addition, gp150-deficient MHV-68 derived from mouse lungs bound less well to spleen cells than wild-type virus. Thus, gp150 is highly similar in function in vitro to the Epstein-Barr virus gp350/220. These results suggest a role for these analogous proteins in mononucleosis and have implications for their use as vaccine antigens.
SF2/ASF Binds the Human Papillomavirus Type 16 Late RNA Control Element and Is Regulated during Differentiation of Virus-Infected Epithelial Cells
Authors: McPhillips Maria G. , Veerapraditsin Thanaporn , Cumming Sarah A. , Karali Dimitra , Milligan Steven G. , Boner Winifred , Morgan Iain M. , Graham Sheila V.
Published: September 2004

Pre-mRNA splicing occurs in the spliceosome, which is composed of small ribonucleoprotein particles (snRNPs) and many non-snRNP components. SR proteins, so called because of their C-terminal arginine- and serine-rich domains (RS domains), are essential members of this class. Recruitment of snRNPs to 5′ and 3′ splice sites is mediated and promoted by SR proteins. SR proteins also bridge splicing factors across exons to help to define these units and have a central role in alternative and enhancer-dependent splicing. Here, we show that the SR protein SF2/ASF is part of a complex that forms upon the 79-nucleotide negative regulatory element (NRE) that is thought to be pivotal in posttranscriptional regulation of late gene expression in human papillomavirus type 16 (HPV-16). However, the NRE does not contain any active splice sites, is located in the viral late 3′ untranslated region, and regulates RNA-processing events other than splicing. The level of expression and extent of phosphorylation of SF2/ASF are upregulated with epithelial differentiation, as is subcellular distribution, specifically in HPV-16-infected epithelial cells, and expression levels are controlled, at least in part, by the virus transcription regulator E2.
Profile of Resistance of Human Immunodeficiency Virus to Mannose-Specific Plant Lectins
Authors: Balzarini Jan , Van Laethem Kristel , Hatse Sigrid , Vermeire Kurt , De Clercq Erik , Peumans Willy , Van Damme Els , Vandamme Anne-Mieke , Böhlmstedt Anders , Schols Dominique
Published: September 2004

The mannose-specific plant lectins from the
Amaryllidaceae
family (e.g.,
Hippeastrum
sp. hybrid and
Galanthus nivalis
) inhibit human immunodeficiency virus (HIV) infection of human lymphocytic cells in the higher nanogram per milliliter range and suppress syncytium formation between persistently HIV type 1 (HIV-1)-infected cells and uninfected CD4
+
T cells. These lectins inhibit virus entry. When exposed to escalating concentrations of
G. nivalis
and
Hippeastrum
sp. hybrid agglutinin, a variety of HIV-1(III
B
) strains were isolated after 20 to 40 subcultivations which showed a decreased sensitivity to the plant lectins. Several amino acid changes in the envelope glycoprotein gp120, but not in gp41, of the mutant virus isolates were observed. The vast majority of the amino acid changes occurred at the N glycosylation sites and at the S or T residues that are part of the N glycosylation motif. The degree of resistance to the plant lectins was invariably correlated with an increasing number of mutated glycosylation sites in gp120. The nature of these mutations was entirely different from that of mutations that are known to appear in HIV-1 gp120 under the pressure of other viral entry inhibitors such as dextran sulfate, bicyclams (i.e., AMD3100), and chicoric acid, which also explains the lack of cross-resistance of plant lectin-resistant viruses to any other HIV inhibitor including T-20 and the blue-green algae (cyanobacteria)-derived mannose-specific cyanovirin. The plant lectins represent a well-defined class of anti-HIV (microbicidal) drugs with a novel HIV drug resistance profile different from those of other existing anti-HIV drugs.
Characterization of a Baculovirus Lacking the Alkaline Nuclease Gene
Authors: Okano Kazuhiro , Vanarsdall Adam L. , Rohrmann George F.
Published: September 2004

The
Autographa californica
multiple nucleocapsid nucleopolyhedrovirus (Ac
M
NPV) alkaline nuclease (AN) associates with the baculovirus single-stranded DNA binding protein LEF-3 and possesses both a 5′→3′ exonuclease and an endonuclease activity. These activities are thought to be involved in DNA recombination and replication. To investigate the role of AN in Ac
M
NPV replication, the λ Red system was used to replace the
an
open reading frame with a chloramphenicol acetyltransferase gene (
cat
) and a bacmid containing the Ac
M
NPV genome in
Escherichia coli
. The Ac
M
NPV
an
knockout bacmid (vAcAN-KO/GUS) was unable to propagate in Sf9 cells, although an
an
-rescued bacmid (vAcAN-KO/GUS-Res) propagated normally. In addition, the mutant did not appear to produce budded virions. These data indicated that
an
is an essential baculovirus gene. Slot blot and DpnI assays of DNA replication in Sf9 cells transfected with vAcAN-KO/GUS, vAcAN-KO/GUS-Res, and a wild-type bacmid showed that the vAcAN-KO/GUS bacmid was able to replicate to levels similar to those seen with the vAcAN-KO/GUS-Res and wild-type bacmids at early stages posttransfection. However, at later time points DNA did not accumulate to the levels seen with the repaired or wild-type bacmids. Northern analysis of Sf9 cells transfected with bacmid vAcAN-KO/GUS showed that transcription of late and very late genes was lower at later times posttransfection relative to the results seen with wild-type and vAcAN-KO/GUS-Res bacmids. These data suggest that the
an
gene might be involved in the maturation of viral DNA or packaging of the DNA into virions.
Autoregulation of DNA Binding and Protein Stability of Kaposi's Sarcoma-Associated Herpesvirus ORF50 Protein
Authors: Chang Pey-Jium , Miller George
Published: September 2004

A transcriptional activator encoded in open reading frame 50 (ORF50) of Kaposi's sarcoma-associated herpesvirus (KSHV) initiates the viral lytic cycle. ORF50 protein activates downstream KSHV target genes by at least two mechanisms: direct recognition of response elements in promoter DNA and interaction with cellular proteins bound to promoter DNA. We have identified a multifunctional regulatory region, present in amino acids (aa) 520 to 535 of ORF50 protein, that controls DNA binding and protein stability. Deletion of aa 521 to 534 or mutation of a basic motif (KKRK) in this regulatory region dramatically enhances DNA binding by ORF50 protein, as shown by electrophoretic mobility shift, DNA affinity chromatography, and chromatin immunoprecipitation assays. Deletion of the regulatory region and mutations in the KKRK motif also lead to abundant expression of an electrophoretic mobility variant, ORF50B, which appears to be a form of ORF50 protein that is decreased in posttranslational modification. Enhanced DNA binding and enhanced expression of ORF50B are independent phenomena. The regulatory region likely inhibits DNA binding through interactions with the DNA binding domain in aa 1 to 390 and destabilizes ORF50B through interactions with a domain located in aa 590 to 650. Mutants in the KKRK motif that are enhanced in DNA binding are nonetheless impaired in activating direct targets, such as polyadenylated nuclear RNA, and indirect targets, such as ORF50 itself. The identification of an autoregulatory region emphasizes that the many functions of ORF50 protein must be subject to exquisite control to achieve optimal KSHV lytic-cycle gene expression.
Nuclear Export of the Nonenveloped Parvovirus Virion Is Directed by an Unordered Protein Signal Exposed on the Capsid Surface
Authors: Maroto Beatriz , Valle Noelia , Saffrich Rainer , Almendral José M.
Published: September 2004

It is uncertain whether nonenveloped karyophilic virus particles may actively traffic from the nucleus outward. The unordered amino-terminal domain of the VP2 major structural protein (2Nt) of the icosahedral parvovirus minute virus of mice (MVM) is internal in empty capsids, but it is exposed outside of the shell through the fivefold axis of symmetry in virions with an encapsidated single-stranded DNA genome, as well as in empty capsids subjected to a heat-induced structural transition. In productive infections of transformed and normal fibroblasts, mature MVM virions were found to efficiently exit from the nucleus prior to cell lysis, in contrast to the extended nuclear accumulation of empty capsids. Newly formed mutant viruses lacking the three phosphorylated serine residues of 2Nt were hampered in their exit from the human transformed NB324K nucleus, in correspondence with the capacity of 2Nt to drive microinjected phosphorylated heated capsids out of the nucleus. However, in normal mouse A9 fibroblasts, in which the MVM capsid was phosphorylated at similar sites but with a much lower rate, the nuclear exit of virions and microinjected capsids harboring exposed 2Nt required the infection process and was highly sensitive to inhibition of the exportin CRM1 in the absence of a demonstrable interaction. Thus, the MVM virion exits the nucleus by accessing nonconventional export pathways relying on cell physiology that can be intensified by infection but in which the exposure of 2Nt remains essential for transport. The flexible 2Nt nuclear transport signal may illustrate a common structural solution used by nonenveloped spherical viruses to propagate in undamaged host tissues.
Forced Selection of a Human Immunodeficiency Virus Type 1 Variant That Uses a Non-Self tRNA Primer for Reverse Transcription: Involvement of Viral RNA Sequences and the Reverse Transcriptase Enzyme
Authors: Abbink Truus E. M. , Beerens Nancy , Berkhout Ben
Published: September 2004

Human immunodeficiency virus type 1 uses the tRNA
3
Lys
molecule as a selective primer for reverse transcription. This primer specificity is imposed by sequence complementarity between the tRNA primer and two motifs in the viral RNA genome: the primer-binding site (PBS) and the primer activation signal (PAS). In addition, there may be specific interactions between the tRNA primer and viral proteins, such as the reverse transcriptase (RT) enzyme. We constructed viruses with mutations in the PAS and PBS that were designed to employ the nonself primer tRNA
Pro
or tRNA
1,2
Lys
. These mutants exhibited a severe replication defect, indicating that additional adaptation of the mutant virus is required to accommodate the new tRNA primer. Multiple independent virus evolution experiments were performed to select for fast-replicating variants. Reversion to the wild-type PBS-lys3 sequence was the most frequent escape route. However, we identified one culture in which the virus gained replication capacity without reversion of the PBS. This revertant virus eventually optimized the PAS motif for interaction with the nonself primer. Interestingly, earlier evolution samples revealed a single amino acid change of an otherwise well-conserved residue in the RNase H domain of the RT enzyme, implicating this domain in selective primer usage. We demonstrate that both the PAS and RT mutations improve the replication capacity of the tRNA
1,2
Lys
-using virus.
Structure and Mechanistic Analysis of the Anti-Human Immunodeficiency Virus Type 1 Antibody 2F5 in Complex with Its gp41 Epitope
Authors: Ofek Gilad , Tang Min , Sambor Anna , Katinger Hermann , Mascola John R. , Wyatt Richard , Kwong Peter D.
Published: September 2004

The membrane-proximal region of the ectodomain of the gp41 envelope glycoprotein of human immunodeficiency virus type 1 (HIV-1) is the target of three of the five broadly neutralizing anti-HIV-1 antibodies thus far isolated. We have determined crystal structures of the antigen-binding fragment for one of these antibodies, 2F5, in complex with 7-mer, 11-mer, and 17-mer peptides of the gp41 membrane-proximal region, at 2.0-, 2.1-, and 2.2-Å resolutions, respectively. The structures reveal an extended gp41 conformation, which stretches over 30 Å in length. Contacts are made with five complementarity-determining regions of the antibody as well as with nonpolymorphic regions. Only one exclusive charged face of the gp41 epitope is bound by 2F5, while the nonbound face, which is hydrophobic, may be hidden due to occlusion by other portions of the ectodomain. The structures reveal that the 2F5 antibody is uniquely built to bind to an epitope that is proximal to a membrane surface and in a manner mostly unaffected by large-scale steric hindrance. Biochemical studies with proteoliposomes confirm the importance of lipid membrane and hydrophobic context in the binding of 2F5 as well as in the binding of 4E10, another broadly neutralizing antibody that recognizes the membrane-proximal region of gp41. Based on these structural and biochemical results, immunization strategies for eliciting 2F5- and 4E10-like broadly neutralizing anti-HIV-1 antibodies are proposed.
The Human Papillomavirus Type 8 E2 Protein Suppresses β4-Integrin Expression in Primary Human Keratinocytes
Authors: Oldak Monika , Smola Hans , Aumailley Monique , Rivero Francisco , Pfister Herbert , Smola-Hess Sigrun
Published: September 2004

Human papillomaviruses (HPVs) infect keratinocytes of skin and mucosa. Homeostasis of these constantly renewing, stratified epithelia is maintained by balanced keratinocyte proliferation and terminal differentiation. Instructions from the extracellular matrix engaging integrins strongly regulate these keratinocyte functions. The papillomavirus life cycle parallels the differentiation program of stratified epithelia, and viral progeny is produced only in terminally differentiating keratinocytes. Whereas papillomavirus oncoproteins can inhibit keratinocyte differentiation, the viral transcription factor E2 seems to counterbalance the impact of oncoproteins. In this study we show that high expression of HPV type 8 (HPV8) E2 in cultured primary keratinocytes leads to strong down-regulation of β4-integrin expression levels, partial reduction of β1-integrin, and detachment of transfected keratinocytes from underlying structures. Unlike HPV18 E2-expressing keratinocytes, HPV8 E2 transfectants did not primarily undergo apoptosis. HPV8 E2 partially suppressed β4-integrin promoter activity by binding to a specific E2 binding site leading to displacement of at least one cellular DNA binding factor. To our knowledge, we show for the first time that specific E2 binding contributes to regulation of a cellular promoter. In vivo, decreased β4-integrin expression is associated with detachment of keratinocytes from the underlying basement membrane and their egress from the basal to suprabasal layers. In papillomavirus disease, β4-integrin down-regulation in keratinocytes with higher E2 expression may push virally infected cells into the transit-amplifying compartment and ensure their commitment to the differentiation process required for virus replication.
The Signal Peptide of the Junín Arenavirus Envelope Glycoprotein Is Myristoylated and Forms an Essential Subunit of the Mature G1-G2 Complex
Authors: York Joanne , Romanowski Victor , Lu Min , Nunberg Jack H.
Published: September 2004

Arenaviruses comprise a diverse family of rodent-borne viruses that are responsible for recurring and emerging outbreaks of viral hemorrhagic fevers worldwide. The Junín virus, a member of the New World arenaviruses, is endemic to the pampas grasslands of Argentina and is the etiologic agent of Argentine hemorrhagic fever. In this study, we have analyzed the assembly and function of the Junín virus envelope glycoproteins. The mature envelope glycoprotein complex is proteolytically processed from the GP-C precursor polypeptide and consists of three noncovalently associated subunits, G1, G2, and a stable 58-amino-acid signal peptide. This tripartite organization is found both on virions of the attenuated Candid 1 strain and in cells expressing the pathogenic MC2 strain GP-C gene. Replacement of the Junín virus GP-C signal peptide with that of human CD4 has little effect on glycoprotein assembly while abolishing the ability of the G1-G2 complex to mediate pH-dependent cell-cell fusion. In addition, we demonstrate that the Junín virus GP-C signal peptide subunit is myristoylated at its N-terminal glycine. Alanine substitution for the modified glycine residue in the GP-C signal peptide does not affect formation of the tripartite envelope glycoprotein complex but markedly reduces its membrane fusion activity. In contrast to the classical view that signal peptides act primarily in targeting nascent polypeptides to the endoplasmic reticulum, we suggest that the signal peptide of the arenavirus GP-C may serve additional functions in envelope glycoprotein structure and trafficking.
Identification of Basal Promoter and Enhancer Elements in an Untranslated Region of the TT Virus Genome
Authors: Suzuki Tetsuro , Suzuki Ryosuke , Li Jin , Hijikata Minako , Matsuda Mami , Li Tiang-Cheng , Matsuura Yoshiharu , Mishiro Shunji , Miyamura Tatsuo
Published: September 2004

The regulation of TT virus (TTV) gene expression was characterized. Transient-transfection assays using reporter constructs revealed that a 113-nucleotide (nt) sequence within the untranslated region, proximal to the transcription initiation site and containing a TATA box motif, has a basal promoter activity. This sequence is well conserved among different TTV genotypes. Upstream stimulating factor bound to a consensus binding motif within this region and positively regulates TTV transcription. Furthermore, a 488-nt region upstream of the basal promoter exhibited enhancer activity, presumably in a cell type-specific manner. This study illustrates some of the mechanisms involved in the transcriptional regulation of TTV.
Activation by Inflammatory Stimuli Increases Neutrophil Binding of Human Immunodeficiency Virus Type 1 and Subsequent Infection of Lymphocytes
Authors: Gabali Ali M. , Anzinger Joshua J. , Spear Gregory T. , Thomas Larry L.
Published: September 2004

Resting neutrophils bind human immunodeficiency virus type 1 (HIV-1) and efficiently transfer infection to lymphocytes. The present study shows that a brief activation by inflammatory stimuli increases the neutrophil binding levels of both R5 and X4 isolates of HIV-1 at least twofold. The binding occurs independently of CD4, gp120, and incubation temperature and is observed with HIV-1 propagated either in lymphocytes or in HEK293 cells. Significantly, HIV-1 bound to the activated neutrophils accelerates the infection of activated lymphocytes compared to free HIV-1 or to HIV-1 bound to resting neutrophils. It is proposed that these events may contribute to the increased risk of HIV-1 transmission at sites of mucosal infection.
Depot differences in steroid receptor expression in adipose tissue: possible role of the local steroid milieu
Authors: Rodriguez-Cuenca S. , Monjo M. , Proenza A. M. , Roca P.
Published: September 2004

Sex hormones play an important role in adipose tissue metabolism by activating specific receptors that alter several steps of the lipolytic and lipogenic signal cascade in depot- and sex-dependent manners. However, studies focusing on steroid receptor status in adipose tissue are scarce. In the present study, we analyzed steroid content [testosterone (T), 17β-estradiol (17β-E2), and progesterone (P4)] and steroid receptor mRNA levels in different rat adipose tissue depots. As expected, T levels were higher in males than in females ( P = 0.031), whereas the reverse trend was observed for P4 ( P < 0.001). It is noteworthy that 17β-E2 adipose tissue levels were higher in inguinal than in the rest of adipose tissues for both sexes, where no sex differences in 17β-E2 tissue levels were noted ( P = 0.010 for retroperitoneal, P = 0.005 for gonadal, P = 0.018 for mesenteric). Regarding steroid receptor levels, androgen (AR) and estrogen receptor (ER)α and ERβ densities were more clearly dependent on adipose depot location than on sex, with visceral depots showing overall higher mRNA densities than their subcutaneous counterparts. Besides, expression of ERα predominated over ERβ expression, and progesterone receptor (PR-B form and PR-A+B form) mRNAs were identically expressed regardless of anatomic depot and sex. In vitro studies in 3T3-L1 cells showed that 17β-E2 increased ERα ( P = 0.001) and AR expression ( P = 0.001), indicating that estrogen can alter estrogenic and androgenic signaling in adipose tissue. The results highlighted in this study demonstrate important depot-dependent differences in the sensitivity of adipose tissues to sex hormones between visceral and subcutaneous depots that could be related to metabolic situations observed in response to sex hormones.
Relationship Between Cardiovascular Risk as Predicted by Established Risk Scores Versus Plaque Progression as Measured by Serial Intravascular Ultrasound in Left Main Coronary Arteries
Authors: von Birgelen Clemens , Hartmann Marc , Mintz Gary S. , van Houwelingen K. Gert , Deppermann Nadine , Schmermund Axel , Böse Dirk , Eggebrecht Holger , Neumann Till , Gössl Mario , Wieneke Heinrich , Erbel Raimund
Published: September 2004

Background—

Intravascular ultrasound (IVUS) is increasingly used as an end point in studies aimed at reducing progression or inducing regression of coronary artery disease. However, data linking serial changes by IVUS with clinical outcomes are scarce.

Methods and Results—

In the absence of a validated risk score for secondary prevention, we compared 3 established risk scores for primary prevention—PROCAM, SCORE, and Framingham—with plaque progression and lumen reduction as assessed with serial IVUS (follow-up, 18±9 months) in atherosclerotic left main coronary arteries of 56 patients with established atherosclerosis. For all 3 algorithms, patients at highest estimated risk of events showed greater plaque progression than patients at lowest risk (
P
<0.05 to <0.01). There were positive linear relationships between the risk of clinical events and plaque progression (
r
=0.41 to 0.60;
P
<0.002 to <0.0001). This translated into a greater decrease in lumen dimensions with increasing risk (
P
<0.05, PROCAM and SCORE). Risk prediction using the PROCAM algorithm showed the strongest relation with serial IVUS. During follow-up, 18 patients suffered from adverse cardiovascular events; these patients had an annual plaque progression that was significantly greater than other patients (25.2±19.4% versus 5.9±15.6%,
P
<0.001).

Conclusions—

There was a positive linear relationship between the estimated risk of clinical events derived from all 3 established risk-score algorithms and the extent of plaque progression measured by serial IVUS. This translated into stenosis progression (reduction in lumen dimensions) with increasing clinical risk.