bluuebunny/crossref_metadata_2025 huggingface dataset:
Thalamic Atrophy in Childhood Absence Epilepsy
Authors: Chan Chow Huat (Patrick) , Briellmann Regula S. , Pell Gaby S. , Scheffer Ingrid E. , Abbott David F. , Jackson Graeme D.
Published: February 2006

Summary:  Purpose: Patients with childhood absence epilepsy (CAE) have normal clinical magnetic resonance imaging (MRI) studies. The presence of abnormalities in corticothalamic networks has been suggested to be the functional basis of absence seizure generation. We assessed whether structural grey and white matter volume changes of these areas occurred in patients with absence seizures by using optimized voxel‐based morphometry (VBM).

Methods: We recruited 13 patients with a clinical and EEG diagnosis of CAE (mean age at examination, 17 ± 8 years) and compared them with a consecutive series of 109 controls (mean age, 29 ± 9 years). The 3 tesla MRI examination included a 3D T1‐weighted sequence, which was analyzed with an optimized VBM protocol using the SPM2 package. The threshold was set at p < 0.05, corrected for multiple comparisons.

Results: Compared with controls, CAE patients showed areas of grey matter decrease in both thalami and in the subcallosal gyrus. White matter decrease was found in the extranuclear subcortical area and in the white matter of the basal forebrain. Grey and white matter increase was restricted to small clusters of cortical and subcortical areas.

Conclusions: Evidence exists of subcortical grey and white matter volume reduction in CAE patients. Bilateral thalamic atrophy may be either a result of damage from seizures (as in hippocampal sclerosis) or a reflection of a primary underlying pathology as the cause of absence seizures.
Defining Intractability: Comparisons among Published Definitions
Authors: Berg Anne T. , Kelly Molly M.
Published: February 2006

Summary:  Purpose: Intractable epilepsy is the focus of much research; however, this concept is defined in no single way. Individual studies use different definitions, creating difficulties for comparisons of results across studies. A head‐to‐head comparison of definitions could highlight these differences and motivate the development of consensus guidelines.

Methods: Within a single prospective study of 613 children in Connecticut with newly diagnosed epilepsy (1993–1997), six different published definitions or indicators for intractability were applied and compared. All definitions were assessed at various times within the first 5 years after diagnosis, with the exact timing reflecting how they were used in their initial reports. Observed and chance‐adjusted agreement (kappa) were computed. The associations of each definition with remission status 7–10 years after diagnosis were quantified with a relative risk.

Results: Depending on the specific definition, the epilepsy of 9–24% of children was considered intractable. Observed agreements among the definitions ranged from a low of 0.83 to a high of 0.96. Kappas ranged from low of 0.45 to 0.79. More similar definitions had higher levels of agreement. All definitions were strongly associated with remission status as of last follow‐up.

Conclusions: Agreement among the different definitions is strong but imperfect. All definitions were significantly associated with longer‐term outcome. No single preferred definition of intractable epilepsy exists. Some discussion within the field of epilepsy and a consensus process should be considered as a future step for enhancing comparability of research efforts and clinical guidelines. Consideration should be given to whether a single definition will suit all purposes or whether different types of definitions are needed for different purposes.
Contralateral Smile and Laughter, but No Mirth, Induced by Electrical Stimulation of the Cingulate Cortex
Authors: Sperli Francesca , Spinelli Laurent , Pollo Claudio , Seeck Margitta
Published: February 2006

Summary:  The cerebral representation of laughter is dissociated. The emotional aspects seem to be processed in the temporal lobe; whereas the motor features apparently rely on the frontal cortex. In a few prior studies of patients in whom laughter was elicited by electrical stimulation (ES), it always was associated with mirth. We report a patient in whom ES in the right cingulate gyrus elicited smile and laughter, but no mirth. At low voltages, smiling was seen first contralaterally and became bilateral with increasing currents. Our observation supports the concept of the motor representation of laughter in the mesial frontal cortex.
Fetal Alcohol Spectrum Disorders in Children Residing in Russian Orphanages: A Phenotypic Survey
Authors: Miller Laurie C. , Chan Wilma , Litvinova Aina , Rubin Arkady , Comfort Kathleen , Tirella Linda , Cermak Sharon , Morse Barbara , Kovalev Igor ,   the Boston‐Murmansk Orphanage Research Team
Published: February 2006

Background: Alcohol use in Russia is among the highest in the world. Over 600,000 children reside in institutional care in Russia, most of them in baby homes and orphanages. The actual prevalence of fetal alcohol spectrum disorders (FASD) among these children is unknown. Therefore, we performed a systematic survey of phenotypic features associated with prenatal alcohol exposure among institutionalized Russian children and related these findings to their growth, development, medical, and social histories.

Methods: Phenotypic screening was conducted of all 234 baby home residents in the Murmansk region of Russia (mean age 21+12.6 months). Phenotypic expression scores were devised based on facial dysmorphology and other readily observable physical findings. Growth measurements from birth, time of placement in the baby home, and at present were analyzed. In addition, the charts of 64% of the children were randomly selected for retrospective review. Information collected included maternal, medical, developmental, and social histories.

Results: Thirteen percent of children had facial phenotype scores highly compatible with prenatal alcohol exposure and 45% had intermediate facial phenotype scores. These scores correlated with maternal gravidity and age. At least 40% of mothers in whom history was available ingested alcohol during pregnancy; some also used illicit drugs and tobacco. Z scores for growth measurements corresponded to phenotypic score, as did the degree of developmental delay. Children with no or mild delay had significantly lower phenotypic scores than those with moderate or severe delay (p=0.04); more than 70% of children with high phenotypic scores were moderately or severely delayed.

Conclusions: More than half of residents of the baby homes in Murmansk, Russia, have intermediate (45%) or high (13%) phenotypic expression scores suggesting prenatal exposure to alcohol. Despite good physical care, stable daily routine, availability of well‐trained specialists, and access to medical care, these vulnerable children show significant growth and developmental delays compared with their institutionalized peers.
A Reexamination of the Corporate Demand for Reinsurance
Authors: Cole Cassandra R. , McCullough Kathleen A.
Published: February 2006

Abstract

This study examines the effect of the state of the international reinsurance market on the demand for reinsurance by U.S. insurers using data from the years 1993 through 2000. Both the overall demand for reinsurance and the utilization of foreign reinsurance by U.S. insurers are explored. In addition to supporting the findings of prior literature related to the traditional motives for the corporate demand for insurance, evidence indicates that the state of the U.S. reinsurance industry impacts the amount of reinsurance demanded by U.S. insurers. The study also investigates reasons why U.S. insurers utilize a reinsurance program composed of both U.S. and foreign reinsurers. The results indicate that the decision to utilize some percentage of foreign reinsurance is driven primarily by the financial and operational characteristics of the ceding company such as firm size, group affiliation, and organizational form. However, no support is found for the hypothesis that possible differences between the foreign and U.S. reinsurance markets impact the decision to utilize foreign reinsurance.
Thirty‐One Years of Clinical Experience with “Nuclear‐Powered” Pacemakers
Authors: PARSONNET VICTOR , DRILLER JACK , COOK DEBRA , RIZVI SYED A.
Published: February 2006

From 1973 through 1987, 164 radioisotope powered (“nuclear”) pacemakers were implanted in 139 patients at the Newark Beth Israel Medical Center. Patient survival was much as might be expected from an age group as selected for this program. At 31 years (January 2005), 12 of the 139 patients (9%) were still alive.

The experience reported here encompassed a span of 16 years of implantation with a follow‐up of slightly more than 31 years. The problems encountered along the way were not remarkably different from those encountered in general clinical experience with pacemakers, except that the number of reoperations was fewer. In fact, most patients died with the initial implant in place. Deaths most commonly were due to cardiac causes (54%). The frequency of malignancies was similar to that of the age‐matched population; primary tumor sites were randomly distributed.

These results show that nuclear pacemakers were safe and reliable. Their longevity and the resulting decrease in reoperations offset their greater initial cost.
Uncommon Cause of Syncope in Patient with Bundle Branch Block and Negative Electrophysiological Study
Authors: FRAGAKIS NIKOLAOS , PAPANASTASIOU SOULTANA , SIDOPOULOS EMMANOUIL , KATSARIS GEORGE
Published: February 2006

We report a case study of a patient with bifascicular block, episodes of syncope, and negative electrophysiological study (EPS) who diagnosed to have sinus arrest with the help of an implantable loop recorder. This case emphasizes that atrioventricular (AV) block is not the only mechanism of syncope in patients with bundle branch block (BBB) and negative EPS.
Brain Sex—Testosterone Role in Personality Evolution; Females and Males are Different?
Authors: Yassin Aksam A.
Published: February 2006

The genders are different because their brains are different. The brain is differently constructed in men and in women; it processes information in a different way, which results in different perceptions, priorities and behaviour. Men and women are equal only in their common membership to the same species, humankind.

The influence of testosterone on the prenatal brain is producing differences in personalities and social behaviours of this humankind.

The extraordinary journey from the sexual differentiation from the prenatal brain to the gender differences inherent in kindergarten play styles, classroom abilities and adult attitudes towards love, sex and marriage and social life in general have been analysed within the last 20 years.
Testosterone Restores Diabetes-Induced Erectile Dysfunction and Sildenafil Responsiveness in Two Distinct Animal Models of Chemical Diabetes
Authors: Zhang Xin-Hua , Filippi Sandra , Morelli Annamaria , Vignozzi Linda , Luconi Michaela , Donati Silvia , Forti Gianni , Maggi Mario
Published: February 2006

Introduction

Hypogonadism is often associated with diabetes and both conditions represent major risk factors for erectile dysfunction (ED).

Aim

To investigate the role of hypogonadism on phosphodiesterase type 5 (PDE5) expression and sildenafil responsiveness in diabetes.

Methods

Two different models of experimental diabetes were used: (i) alloxan-induced diabetic rabbit; and (ii) streptozotocin (STZ)-induced diabetic rat. In both experimental models, animals were separated into three groups: control, diabetic, diabetic supplemented with testosterone (T) enanthate. Rabbits were used for “in vitro” experiments. Conversely, each rats group was further subdivided: no further treatment or acute sildenafil dosing (25 mg/kg, 1 hour before “in vivo” electrical stimulation [ES]).

Main Outcome Measure

Erectile capacity was evaluated either by “in vitro” contractility study (alloxan-induced diabetic rabbit) and “in vivo” evaluation of erectile response elicited by ES of cavernous nerve (STZ-induced diabetic rats). Also endothelial nitric oxide synthase, neural nitric oxide synthase (nNOS), and PDE5 protein (Western blot) and mRNA (quantitative real-time reverse transcriptase polymerase chain reaction [RT-PCR]) expression were measured in rat penile samples of each group.

Results

In both models, hypogonadism was observed, characterized by reduced T and atrophy of androgen-dependent accessory glands. T substitution completely reverted hypogonadism and diabetes-induced penile hyposensitivity to “in vitro” (acetylcholine, rabbit) or “in vivo” (ES, rat) relaxant stimuli, along with nNOS expression, which was reduced (P < 0.05) in STZ rats. In diabetic animals, T substitution reinstated sildenafil-induced enhancement of both “in vitro” nitric oxide donor (NCX 4040) relaxant effect (rabbit) and “in vivo” ES-induced erection (rat). PDE5 was reduced in diabetic STZ rats (P < 0.05) and normalized by T. In STZ rats, sodium nitroprusside (SNP) intracavernous injection induced a more sustained erection than in control rats, which was no further enhanced by sildenafil. T substitution normalized both hyper-responsiveness to SNP and sildenafil efficacy.

Results

In two models of diabetes T deficiency underlies biochemical alterations leading to ED. Normalizing T in diabetes restores nNOS and PDE5, and reinstates sensitivity to relaxant stimuli and responsiveness to sildenafil.
The Types of Information Contained in Company Reliability Reports from the Better Business Bureau
Authors: GARRETT DENNIS E.
Published: February 2006

Consumer requests for company reliability reports from the Better Business Bureau (BBB) have increased dramatically in recent years. However, no prior research has analyzed on a national level the types of information contained in these reports. This study reveals that the BBB had reliability reports for 69.1% of auto dealers, 58.9% of movers, and 43.8% of roofers. No significant difference was found between the numbers of complaints filed against BBB member and nonmember companies. However, significant differences were found in the manner in which member and nonmember companies responded to these complaints. Discussion focuses on the potential usefulness of these reports for consumers, and recommendations are offered for improvements.
Substance, Attribute, and Mode in Spinoza
Authors: Lin Martin
Published: February 2006

Some of Spinoza's most well‐known doctrines concern what kinds of beings there are and how they are related to each other. For example, he claims that: (1) there is only one substance; (2) this substance has infinitely many attributes; (3) this substance is God or nature; (4) each of these attributes express the divine essence; and (5) all else is a mode of the one substance. These claims have so astonished many of his readers that some of them have surely concluded that they must not know what Spinoza means by “substance,”“attribute,” and “mode.” In this article I shall try to explain how Spinoza understands the basic ontological categories denoted by these expressions.
Galois Module Structure of pTh‐Power Classes of Cyclic Extensions of Degree pn
Authors: Mináč Ján , Schultz Andrew , Swallow John
Published: February 2006

In the mid‐1960s Borevic and Faddeev initiated the study of the Galois module structure of groups of pth‐power classes of cyclic extensions K/F of pth‐power degree. They determined the structure of these modules in the case when F is a local field. In this paper we determine these Galois modules for all base fields F. 2000 Mathematics Subject Classification 12F10 (primary), 16D70 (secondary)
Alveolar type I cells protect rat lung epithelium from oxidative injury
Authors: Chen Jiwang , Chen Zhongming , Chintagari Narendranath Reddy , Bhaskaran Manoj , Jin Nili , Narasaraju Telugu , Liu Lin
Published: February 2006

The lung alveolar surface is covered by two morphologically and functionally distinct cells: alveolar epithelial cell types I and II (AEC I and II). The functions of AEC II, including surfactant release, cell differentiation and ion transport, have been extensively studied. However, relatively little is known regarding the physiological functions of AEC I. Global gene expression profiling of freshly isolated AEC I and II revealed that many genes were differentially expressed in AEC I. These genes have a diversity of functions, including cell defence. Nine out of 10 selected genes were verified by quantitative real‐time PCR. Two genes, apolipoprotein E (Apo E) and transferrin, were further characterized and functionally studied. Immunohistochemistry indicated that both proteins were specifically localized in AEC I. Up‐regulation of Apo E and transferrin was observed in hyperoxic lungs. Functionally, Apo E and transferrin play a protective role against oxidative stress in an animal model. Our studies suggest that AEC I is not just a simple barrier for gas exchange, but a functional cell that protects alveolar epithelium from injury.
Protein restriction during fetal and neonatal development in the rat alters reproductive function and accelerates reproductive ageing in female progeny
Authors: Guzmán C. , Cabrera R. , Cárdenas M. , Larrea F. , Nathanielsz P. W. , Zambrano E.
Published: February 2006

Recent studies demonstrate long‐term programming of function of specific organ systems resulting from suboptimal environments during fetal life and development up to weaning. Nutrient restriction during pregnancy and lactation impairs overall fetal growth and development. We determined the effects of maternal protein restriction (MPR; 50% normal protein intake) during fetal development and/or lactation in rats on the function and ageing of the reproductive system of female progeny. Rats were fed either a control 20% casein diet (C) or a restricted diet (R) of 10% casein during pregnancy. After delivery mothers received either C or R diet until weaning to provide four groups, CC, RR, CR and RC. We report data on female offspring only. After weaning pups were fed the C diet. MPR increased maternal progesterone, corticosterone, oestradiol and testosterone concentrations at 19 days gestation. Reproductive and somatic phenotype was altered as pup birth weight was decreased, and ano‐genital distance was increased by MPR. Pup corticosterone was decreased at 2 days postnatal (PN) life. Vaginal opening and timing of the first oestrus were delayed in RR and CR and these differences were not related to body weight. At 21 days PN oestradiol in RR and CR and progesterone in RR were reduced; at 70 days PN luteinizing hormone (LH) in all restricted groups was reduced in dioestrus while follicle stimulating hormone (FSH) was unchanged. Cycle length increased between 140 days and 1 year in RR and CR but remained unchanged in CC, providing evidence of premature ageing of reproductive function. Fertility rates declined over the same period in the three experimental groups but not CC. MPR in one of the two experimental periods, either pregnancy or lactation, resulted in decreased pup survival compared with CC and RR. These data show that MPR results in delayed sexual maturation and premature ageing of reproductive function.
Electrostatic Self-Assembly of Binary Nanoparticle Crystals with a Diamond-Like Lattice
Authors: Kalsin Alexander M. , Fialkowski Marcin , Paszewski Maciej , Smoukov Stoyan K. , Bishop Kyle J. M. , Grzybowski Bartosz A.
Published: February 2006

Self-assembly of charged, equally sized metal nanoparticles of two types (gold and silver) leads to the formation of large, sphalerite (diamond-like) crystals, in which each nanoparticle has four oppositely charged neighbors. Formation of these non–close-packed structures is a consequence of electrostatic effects specific to the nanoscale, where the thickness of the screening layer is commensurate with the dimensions of the assembling objects. Because of electrostatic stabilization of larger crystallizing particles by smaller ones, better-quality crystals can be obtained from more polydisperse nanoparticle solutions.
Age-Dependent Poliovirus Replication in the Mouse Central Nervous System Is Determined by Internal Ribosome Entry Site-Mediated Translation
Authors: Kauder Steven , Kan Sherry , Racaniello Vincent R.
Published: February 2006

Mouse cells are not permissive for the replication of human rhinovirus type 2 (HRV2). To determine the role of the HRV2 internal ribosome entry site (IRES) in determining species specificity, a recombinant poliovirus (P1/HRV2) was constructed by substituting the poliovirus IRES with the IRES from HRV2. This recombinant virus replicated in all human and murine cell lines examined, demonstrating that the HRV2 IRES does not limit viral replication in transformed murine cells. P1/HRV2 replicated in the brain and spinal cord in neonatal but not adult mice transgenic for the poliovirus receptor, CD155. Passage of P1/HRV2 in mice led to selection of a virus that caused paralysis in neonatal mice. To determine the relationship between HRV2 IRES-mediated translation and replication of P1/HRV2 in mice, recombinant human adenoviruses were used to express bicistronic mRNAs in murine organs. The results demonstrate that the HRV2 IRES mediates translation in organs of neonatal but not adult mice. These findings show that HRV2 IRES-mediated translation is a determinant of virus replication in the murine brain and spinal cord and suggest that the IRES determines the species specificity of HRV2 infection.
The α-TIF (VP16) Homologue (ETIF) of Equine Herpesvirus 1 Is Essential for Secondary Envelopment and Virus Egress
Authors: von Einem Jens , Schumacher Daniel , O'Callaghan Dennis J. , Osterrieder Nikolaus
Published: February 2006

The equine herpesvirus 1 (EHV-1) α-
trans
-inducing factor homologue (ETIF; VP16-E) is a 60-kDa virion component encoded by
gene 12
(ORF12) that transactivates the immediate-early gene promoter. Here we report on the function of EHV-1 ETIF in the context of viral infection. An ETIF-null mutant from EHV-1 strain RacL11 (vL11ΔETIF) was constructed and analyzed. After transfection of vL11ΔETIF DNA into RK13 cells, no infectious virus could be reconstituted, and only single infected cells or small foci containing up to eight infected cells were detected. In contrast, after transfection of vL11ΔETIF DNA into a complementing cell line, infectious virus could be recovered, indicating the requirement of ETIF for productive virus infection. The growth defect of vL11ΔETIF could largely be restored by propagation on the complementing cell line, and growth on the complementing cell line resulted in incorporation of ETIF in mature and secreted virions. Low- and high-multiplicity infections of RK13 cells with phenotypically complemented vL11ΔETIF virus resulted in titers of virus progeny similar to those used for infection, suggesting that input ETIF from infection was recycled. Ultrastructural studies of vL11ΔETIF-infected cells demonstrated a marked defect in secondary envelopment at cytoplasmic membranes, resulting in very few enveloped virions in transport vesicles or extracellular space. Taken together, our results demonstrate that ETIF has an essential function in the replication cycle of EHV-1, and its main role appears to be in secondary envelopment.
Antigenic Evolution of Vaccine-Derived Polioviruses: Changes in Individual Epitopes and Relative Stability of the Overall Immunological Properties
Authors: Yakovenko Maria L. , Cherkasova Elena A. , Rezapkin Gennady V. , Ivanova Olga E. , Ivanov Alexander P. , Eremeeva Tatyana P. , Baykova Olga Y. , Chumakov Konstantin M. , Agol Vadim I.
Published: February 2006

The Sabin oral poliovirus vaccine (OPV) readily undergoes changes in antigenic sites upon replication in humans. Here, a set of antigenically altered descendants of the three OPV serotypes (76 isolates) was characterized to determine the driving forces behind these changes and their biological implications. The amino acid residues of OPV derivatives that lie within or close to the known antigenic sites exhibited a marked tendency to be replaced by residues characteristic of homotypic wild polioviruses, and these changes may occur very early in OPV evolution. The specific amino acid alterations nicely correlated with serotype-specific changes in the reactivity of certain individual antigenic sites, as revealed by the recently devised monoclonal antibody-based enzyme-linked immunosorbent assay. In comparison to the original vaccine, small changes, if any, in the neutralizing capacity of human or rabbit sera were observed in highly diverged vaccine polioviruses of three serotypes, in spite of strong alterations of certain epitopes. We propose that the common antigenic alterations in evolving OPV strains largely reflect attempts to eliminate fitness-decreasing mutations acquired either during the original selection of the vaccine or already present in the parental strains. Variability of individual epitopes does not appear to be primarily caused by, or lead to, a significant immune evasion, enhancing only slightly, if at all, the capacity of OPV derivatives to overcome immunity in human populations. This study reveals some important patterns of poliovirus evolution and has obvious implications for the rational design of live viral vaccines.
Naïve T-Cell Dynamics in Human Immunodeficiency Virus Type 1 Infection: Effects of Highly Active Antiretroviral Therapy Provide Insights into the Mechanisms of Naïve T-Cell Depletion
Authors: Di Mascio Michele , Sereti Irini , Matthews Lynn T. , Natarajan Ven , Adelsberger Joseph , Lempicki Richard , Yoder Christian , Jones Elizabeth , Chow Catherine , Metcalf Julia A. , Sidorov Igor A. , Dimitrov Dimiter S. , Polis Michael A. , Kovacs Joseph A.
Published: February 2006

Both naïve CD4+and naïve CD8+T cells are depleted in individuals with human immunodeficiency virus type 1 (HIV-1) infection by unknown mechanisms. Analysis of their dynamics prior to and after highly active antiretroviral therapy (HAART) could reveal possible mechanisms of depletion. Twenty patients were evaluated with immunophenotyping, intracellular Ki67 staining, T-cell receptor excision circle (TREC) quantitation in sorted CD4 and CD8 cells, and thymic computed tomography scans prior to and ∼6 and ∼18 months after initiation of HAART. Naïve T-cell proliferation decreased significantly during the first 6 months of therapy (P< 0.01) followed by a slower decline. Thymic indices did not change significantly over time. At baseline, naïve CD4+T-cell numbers were lower than naive CD8+T-cell numbers; after HAART, a greater increase in naïve CD4+T cells than naïve CD8+T cells was observed. A greater relative change (n-fold) in the number of TREC+T cells/μl than in naïve T-cell counts was observed at 6 months for both CD4+(median relative change [n-fold] of 2.2 and 1.7, respectively;P< 0.01) and CD8+T cell pools (1.4 and 1.2;P< 0.01). A more pronounced decrease in the proliferation than the disappearance rate of naïve T cells after HAART was observed in a second group of six HIV-1-infected patients studied by in vivo pulse labeling with bromodeoxyuridine. These observations are consistent with a mathematical model where the HIV-1-induced increase in proliferation of naïve T cells is mostly explained by a faster recruitment into memory cells.
Modeling the Early Events of Severe Acute Respiratory Syndrome Coronavirus Infection In Vitro
Authors: Yen Yu-Ting , Liao Fang , Hsiao Cheng-Hsiang , Kao Chuan-Liang , Chen Yee-Chun , Wu-Hsieh Betty A.
Published: February 2006

The clinical picture of severe acute respiratory syndrome (SARS) is characterized by pulmonary inflammation and respiratory failure, resembling that of acute respiratory distress syndrome. However, the events that lead to the recruitment of leukocytes are poorly understood. To study the cellular response in the acute phase of SARS coronavirus (SARS-CoV)-host cell interaction, we investigated the induction of chemokines, adhesion molecules, and DC-SIGN (dendritic cell-specific ICAM-3-grabbing nonintegrin) by SARS-CoV. Immunohistochemistry revealed neutrophil, macrophage, and CD8 T-cell infiltration in the lung autopsy of a SARS patient who died during the acute phase of illness. Additionally, pneumocytes and macrophages in the patient's lung expressed P-selectin and DC-SIGN. In in vitro study, we showed that the A549 and THP-1 cell lines were susceptible to SARS-CoV. A549 cells produced CCL2/monocyte chemoattractant protein 1 (MCP-1) and CXCL8/interleukin-8 (IL-8) after interaction with SARS-CoV and expressed P-selectin and VCAM-1. Moreover, SARS-CoV induced THP-1 cells to express CCL2/MCP-1, CXCL8/IL-8, CCL3/MIP-1α, CXCL10/IP-10, CCL4/MIP-1β, and CCL5/RANTES, which attracted neutrophils, monocytes, and activated T cells in a chemotaxis assay. We also demonstrated that DC-SIGN was inducible in THP-1 as well as A549 cells after SARS-CoV infection. Our in vitro experiments modeling infection in humans together with the study of a lung biopsy of a patient who died during the early phase of infection demonstrated that SARS-CoV, through a dynamic interaction with lung epithelial cells and monocytic cells, creates an environment conducive for immune cell migration and accumulation that eventually leads to lung injury.
Feline Lentivirus Evolution in Cross-Species Infection Reveals Extensive G-to-A Mutation and Selection on Key Residues in the Viral Polymerase
Authors: Poss Mary , Ross Howard A. , Painter Sally L. , Holley David C. , Terwee Julie A. , VandeWoude Sue , Rodrigo Allen
Published: February 2006

Factors that restrict a virus from establishing productive infection in a new host species are important to understand because cross-species transmission events are often associated with emergent viral diseases. To determine the evolutionary pressures on viruses in new host species, we evaluated the molecular evolution of a feline immunodeficiency virus derived from a wild cougar,
Puma concolor
, during infection of domestic cats. Analyses were based on the coding portion of genome sequences recovered at intervals over 37 weeks of infection of six cats inoculated by either intravenous or oral-nasal routes. All cats inoculated intravenously, but only one inoculated orally-nasally, became persistently viremic. There were notable accumulations of lethal errors and predominance of G-to-A alterations throughout the genome, which were marked in the viral polymerase gene,
pol
. Viral structural (
env
and
gag
) and accessory (
vif
and
orfA
) genes evolved neutrally or were under purifying selection. However, sites under positive selection were identified in reverse transcriptase that involved residues in the nucleotide binding pocket or those contacting the RNA-DNA duplex. The findings of extensive G-to-A alterations in this cross-species infection are consistent with the recently described editing of host cytidine deaminase on lentivirus genomes. Additionally, we demonstrate that the primary site of hypermutation is the viral
pol
gene and the dominant selective force acting on this feline immunodeficiency virus as it replicates in a new host species is on key residues of the virus polymerase.
Development of a cAdVax-Based Bivalent Ebola Virus Vaccine That Induces Immune Responses against both the Sudan and Zaire Species of Ebola Virus
Authors: Wang Danher , Raja Nicholas U. , Trubey Charles M. , Juompan Laure Y. , Luo Min , Woraratanadharm Jan , Deitz Stephen B. , Yu Hong , Swain Benjamin M. , Moore Kevin M. , Pratt William D. , Hart Mary Kate , Dong John Y.
Published: February 2006

Ebola virus (EBOV) causes a severe hemorrhagic fever for which there are currently no vaccines or effective treatments. While lethal human outbreaks have so far been restricted to sub-Saharan Africa, the potential exploitation of EBOV as a biological weapon cannot be ignored. Two species of EBOV,
Sudan ebolavirus
(SEBOV) and
Zaire ebolavirus
(ZEBOV), have been responsible for all of the deadly human outbreaks resulting from this virus. Therefore, it is important to develop a vaccine that can prevent infection by both lethal species. Here, we describe the bivalent cAdVaxE(GPs/z) vaccine, which includes the SEBOV glycoprotein (GP) and ZEBOV GP genes together in a single complex adenovirus-based vaccine (cAdVax) vector. Vaccination of mice with the bivalent cAdVaxE(GPs/z) vaccine led to efficient induction of EBOV-specific antibody and cell-mediated immune responses to both species of EBOV. In addition, the cAdVax technology demonstrated induction of a 100% protective immune response in mice, as all vaccinated C57BL/6 and BALB/c mice survived challenge with a lethal dose of ZEBOV (30,000 times the 50% lethal dose). This study demonstrates the potential efficacy of a bivalent EBOV vaccine based on a cAdVax vaccine vector design.
Improved Gene Delivery to Intestinal Mucosa by Adenoviral Vectors Bearing Subgroup B and D Fibers
Authors: Lecollinet S. , Gavard F. , Havenga M. J. E. , Spiller O. B. , Lemckert A. , Goudsmit J. , Eloit M. , Richardson J.
Published: February 2006

A major obstacle to successful oral vaccination is the lack of antigen delivery systems that are both safe and highly efficient. Conventional replication-incompetent adenoviral vectors, derived from human adenoviruses of subgroup C, are poorly efficient in delivering genetic material to differentiated intestinal epithelia. To date, 51 human adenovirus serotypes have been identified and shown to recognize different cellular receptors with different tissue distributions. This natural diversity was exploited in the present study to identify suitable adenoviral vectors for efficient gene delivery to the human intestinal epithelium. In particular, we compared the capacities of a library of adenovirus type 5-based vectors pseudotyped with fibers of several human serotypes for transduction, binding, and translocation toward the basolateral pole in human and murine tissue culture models of differentiated intestinal epithelia. In addition, antibody-based inhibition was used to gain insight into the molecular interactions needed for efficient attachment. We found that vectors differing merely in their fiber proteins displayed vastly different capacities for gene transfer to differentiated human intestinal epithelium. Notably, vectors bearing fibers derived from subgroup B and subgroup D serotypes transduced the apical pole of human epithelium with considerably greater efficiency than a subgroup C vector. Such efficiency was correlated with the capacity to use CD46 or sialic acid-containing glycoconjugates as opposed to CAR as attachment receptors. These results suggest that substantial gains could be made in gene transfer to digestive epithelium by exploiting the tropism of existing serotypes of human adenoviruses.
Th-1-Type Cytotoxic CD8+T-Lymphocyte Responses to Simian Immunodeficiency Virus (SIV) Are a Consistent Feature of Natural SIV Infection in Sooty Mangabeys
Authors: Wang Zichun , Metcalf Benjamin , Ribeiro Ruy M. , McClure Harold , Kaur Amitinder
Published: February 2006

Sooty mangabeys are a natural host of simian immunodeficiency virus (SIV) that remain asymptomatic and do not exhibit increased immune activation or increased T-lymphocyte turnover despite sustained high levels of SIV viremia. In this study we asked whether an altered immune response to SIV contributes to the lack of immunopathology in sooty mangabeys as opposed to species with pathogenic lentivirus infection. SIV-specific cellular immune responses were investigated in a cohort of 25 sooty mangabeys with natural SIV infection. Gamma interferon (IFN-γ) enzyme-linked immunospot (ELISPOT) assay responses targeting a median of four SIV proteins were detected in all 25 mangabeys and were comparable in magnitude to those of 13 rhesus macaques infected with SIVmac251 for more than 6 months. As with rhesus macaques, Th2 ELISPOT responses to SIV were absent or >10-fold lower than the IFN-γ ELISPOT response to the same SIV protein. The SIV-specific ELISPOT response was predominantly mediated by CD8+T lymphocytes; the frequency of circulating SIV-specific CD8+T lymphocytes ranged between 0.11% and 3.26% in 13 mangabeys. Functionally, the SIV-specific CD8+T lymphocytes were cytotoxic; secreted IFN-γ, tumor necrosis factor alpha, and macrophage inflammatory protein 1β; and had an activated effector phenotype. Although there was a trend toward higher frequencies of SIV-specific CD8+T lymphocytes in mangabeys with lower viral loads, a significant inverse correlation between SIV viremia and SIV-specific cellular immunity was not detected. The consistent detection of Th1-type SIV-specific cellular immune responses in naturally infected sooty mangabeys suggests that immune attenuation is neither a feature of nor a requirement for maintenance of nonpathogenic SIV infection in its natural host.
Innate Immune Responses to Herpes Simplex Virus Type 2 Influence Skin Homing Molecule Expression by Memory CD4+Lymphocytes
Authors: Koelle David M. , Huang Jay , Hensel Michael T. , McClurkan Christopher L.
Published: February 2006

Herpes simplex virus (HSV) infections of humans are characterized by intermittent, lytic replication in epithelia. Circulating HSV-specific CD4 T cells express lower levels of preformed cutaneous lymphocyte-associated antigen (CLA), a skin-homing receptor, than do circulating HSV-specific CD8 T cells but, paradoxically, move into infected skin earlier than CD8 cells. Memory CD4 T cells develop strong and selective expression of CLA and E-selectin ligand while responding to HSV antigen in vitro. We now show that interleukin-12, type I interferon, and transforming growth factor beta are each involved in CLA expression by memory HSV type 2 (HSV-2)-specific CD4 T cells in peripheral blood mononuclear cells (PBMC). A reduction of the number of monocytes and dendritic cells from PBMC reduces CLA expression by HSV-2-responsive CD4 lymphoblasts, while their reintroduction restores this phenotype, identifying these cells as possible sources of CLA-promoting cytokines. Plasmacytoid dendritic cells are particularly potent inducers of CLA on HSV-reactive CD4 T cells. These observations are consistent with cooperation between innate and acquired immunity to promote a pattern of homing receptor expression that is physiologically appropriate for trafficking to infected tissues.
Rescue of Infectious Rift Valley Fever Virus Entirely from cDNA, Analysis of Virus Lacking the NSs Gene, and Expression of a Foreign Gene
Authors: Ikegami Tetsuro , Won Sungyong , Peters C. J. , Makino Shinji
Published: February 2006

Rift Valley fever virus (RVFV) (genus
Phlebovirus
, family
Bunyaviridae
) has a tripartite negative-strand genome, causes a mosquito-borne disease that is endemic in sub-Saharan African countries and that also causes large epidemics among humans and livestock. Furthermore, it is a bioterrorist threat and poses a risk for introduction to other areas. In spite of its danger, neither veterinary nor human vaccines are available. We established a T7 RNA polymerase-driven reverse genetics system to rescue infectious clones of RVFV MP-12 strain entirely from cDNA, the first for any phlebovirus. Expression of viral structural proteins from the protein expression plasmids was not required for virus rescue, whereas NSs protein expression abolished virus rescue. Mutants of MP-12 partially or completely lacking the NSs open reading frame were viable. These NSs deletion mutants replicated efficiently in Vero and 293 cells, but not in MRC-5 cells. In the latter cell line, accumulation of beta interferon mRNA occurred after infection by these NSs deletion mutants, but not after infection by MP-12. The NSs deletion mutants formed larger plaques than MP-12 did in Vero E6 cells and failed to shut off host protein synthesis in Vero cells. An MP-12 mutant carrying a luciferase gene in place of the NSs gene replicated as efficiently as MP-12 did, produced enzymatically active luciferase during replication, and stably retained the luciferase gene after 10 virus passages, representing the first demonstration of foreign gene expression in any bunyavirus. This reverse genetics system can be used to study the molecular virology of RVFV, assess current vaccine candidates, produce new vaccines, and incorporate marker genes into animal vaccines.
Exploring the DNA Binding Interactions of the Kaposi's Sarcoma-Associated Herpesvirus Lytic Switch Protein by Selective Amplification of Bound Sequences In Vitro
Authors: Ziegelbauer Joseph , Grundhoff Adam , Ganem Don
Published: February 2006

The lytic switch protein RTA of Kaposi's sarcoma-associated herpesvirus (KSHV) can be targeted to DNA by either direct sequence-specific recognition or via protein-protein interactions with host transcription factors. We have searched for sequences capable of direct RTA binding by screening synthetic oligonucleotide pools and KSHV genomic libraries for RTA-interacting elements, using repeated cycles of in vitro binding followed by amplification of the bound sequences. Multiple low-affinity sequences were recovered from the random pools, with generation of only a weak consensus sequence. The genomic library, by contrast, yielded many biologically relevant fragments, most of which could be shown to interact with RTA in vitro and some of which likely play important regulatory roles in vivo. Surprisingly, the most highly selected fragment came from the promoter of a late gene (gB) and contained at least two direct RTA binding sites, as well as one RBP-Jκ binding site. This raises the possibility that some late KSHV genes may also be subject to direct RTA regulation, though indirect models are not excluded.
Simian Immunodeficiency Virus Engrafted with Human Immunodeficiency Virus Type 1 (HIV-1)-Specific Epitopes: Replication, Neutralization, and Survey of HIV-1-Positive Plasma
Authors: Yuste Eloisa , Sanford Hannah B. , Carmody Jill , Bixby Jacqueline , Little Susan , Zwick Michael B. , Greenough Tom , Burton Dennis R. , Richman Douglas D. , Desrosiers Ronald C. , Johnson Welkin E.
Published: February 2006

To date, only a small number of anti-human immunodeficiency virus type 1 (HIV-1) monoclonal antibodies (MAbs) with relatively broad neutralizing activity have been isolated from infected individuals. Adequate techniques for defining how frequently antibodies of these specificities arise in HIV-infected people have been lacking, although it is generally assumed that such antibodies are rare. In order to create an epitope-specific neutralization assay, we introduced well-characterized HIV-1 epitopes into the heterologous context of simian immunodeficiency virus (SIV). Specifically, epitope recognition sequences for the 2F5, 4E10, and 447-52D anti-HIV-1 neutralizing monoclonal antibodies were introduced into the corresponding regions of SIVmac239 by site-directed mutagenesis. Variants with 2F5 or 4E10 recognition sequences in gp41 retained replication competence and were used for neutralization assays. The parental SIVmac239 and the neutralization-sensitive SIVmac316 were not neutralized by the 2F5 and 4E10 MAbs, nor were they neutralized significantly by any of the 96 HIV-1-positive human plasma samples that were tested. The SIV239-2F5 and SIV239-4E10 variants were specifically neutralized by the 2F5 and 4E10 MAbs, respectively, at concentrations within the range of what has been reported previously for HIV-1 primary isolates (J. M. Binley et al., J. Virol.78:13232-13252, 2004). The SIV239-2F5 and SIV239-4E10 epitope-engrafted variants were used as biological screens for the presence of neutralizing activity of these specificities. None of the 92 HIV-1-positive human plasma samples that were tested exhibited significant neutralization of SIV239-2F5. One plasma sample exhibited >90% neutralization of SIV239-4E10, but this activity was not competed by a 4E10 target peptide and was not present in concentrated immunoglobulin G (IgG) or IgA fractions. We thus confirm by direct analysis that neutralizing activities of the 2F5 and 4E10 specificities are either rare among HIV-1-positive individuals or, if present, represent only a very small fraction of the total neutralizing activity in any given plasma sample. We further conclude that the structures of gp41 from SIVmac239 and HIV-1 are sufficiently similar such that epitopes engrafted into SIVmac239 can be readily recognized by the cognate anti-HIV-1 monoclonal antibodies.
Interaction of the Adenovirus Type 5 E4 Orf3 Protein with Promyelocytic Leukemia Protein Isoform II Is Required for ND10 Disruption
Authors: Hoppe Anne , Beech Stephanie J. , Dimmock John , Leppard Keith N.
Published: February 2006

Nuclear domain 10 (ND10s), or promyelocytic leukemia protein (PML) nuclear bodies, are spherical nuclear structures that require PML proteins for their formation. Many viruses target these structures during infection. The E4 Orf3 protein of adenovirus 5 (Ad5) rearranges ND10s, causing PML to colocalize with Orf3 in nuclear tracks or fibers. There are six different PML isoforms (I to VI) present at ND10s, all sharing a common N terminus but with structural differences at their C termini. In this study, PML II was the only one of these six isoforms that was found to interact directly and specifically with Ad5 E4 Orf3 in vitro and in vivo; these results define a new Orf3 activity. Three of a series of 18 mutant Orf3 proteins were unable to interact with PML II; these were also unable to cause ND10 rearrangement. Moreover, in PML-null cells that contained neoformed ND10s comprising a single PML isoform, only ND10s formed of PML II were rearranged by Orf3. These data show that the interaction between Orf3 and PML II is necessary for ND10 rearrangement to occur. Finally, Orf3 was shown to self-associate in vitro. This activity was absent in mutant Orf3 proteins that were unable to form tracks and to bind PML II. Thus, Orf3 oligomerization may mediate the formation of nuclear tracks in vivo and may also be important for PML II binding.
Inhibition of Interferon Signaling by the Kaposi's Sarcoma-Associated Herpesvirus Full-Length Viral Interferon Regulatory Factor 2 Protein
Authors: Fuld Suzanne , Cunningham Charles , Klucher Kevin , Davison Andrew J. , Blackbourn David J.
Published: February 2006

Interferon (IFN) signal transduction involves interferon regulatory factors (IRF). Kaposi's sarcoma-associated herpesvirus (KSHV) encodes four IRF homologues: viral IRF 1 (vIRF-1) to vIRF-4. Previous functional studies revealed that the first exon of vIRF-2 inhibited alpha/beta interferon (IFN-α/β) signaling. We now show that full-length vIRF-2 protein, translated from two spliced exons, inhibited both IFN-α- and IFN-λ-driven transactivation of a reporter promoter containing the interferon stimulated response element (ISRE). Transactivation of the ISRE promoter by IRF-1 was negatively regulated by vIRF-2 protein as well. Transactivation of a full-length IFN-β reporter promoter by either IRF-3 or IRF-1, but not IRF-7, was also inhibited by vIRF-2 protein. Thus, vIRF-2 protein is an interferon induction antagonist that acts pleiotropically, presumably facilitating KSHV infection and dissemination in vivo.