bluuebunny/crossref_metadata_2025 huggingface dataset:
Activation of Innate Immunity in Healthy
Macaca mulatta
Macaques by a Single Subcutaneous Dose of GMP CpG 7909: Safety Data and Interferon-Inducible Protein-10 Kinetics for Humans and Macaques
Authors: Stewart V. Ann , McGrath Shannon , Krieg Arthur M. , Larson Noelle S. , Angov Evelina , Smith Christopher L. , Brewer Thomas G. , Heppner D. Gray
Published: December 2007

Following a demonstration that mouse-optimized cytosine-guanosine dinucleotide (CpG) oligodeoxynucleotides stimulated innate immune protection against intracellular pathogens, we tested the ability of CpG 7909, a primate-optimized Toll-like receptor 9 (TLR9) agonist, to stimulate rhesus macaques to produce interferon-inducible protein-10 (IP-10), a biomarker of immune activation. This study was performed prior to a similar trial with humans in order to facilitate the development of CpG 7909 as an immunomodulator for biodefense. A single subcutaneous dose of clinical-grade CpG 7909 was given to four groups of healthy adult rhesus macaques (0-mg dose [
n
= 5], 0.75-mg dose [
n
= 9], 1.5-mg dose [
n
= 9], and 3.0-mg dose [
n
= 9]). Directed physical examination findings, clinical laboratory values, and serum IP-10 concentrations were collected at scheduled intervals for 28 days. All three dose levels of CpG 7909 were safe and not associated with significant clinical or laboratory abnormality. The time to peak serum IP-10 concentration was 1.0 days at the 0.75-mg dose and 0.5 days at the 1.5- and 3.0-mg doses. A dose-dependent response was observed for the magnitude and duration of IP-10 concentrations, which remained significantly above baseline for 3 days for the 3.0-mg and 1.5-mg dose groups but above baseline for only 2 days for the 0.75-mg dose group. There were no nonresponders to CpG 7909. These rhesus macaque safety and IP-10 response data closely parallel a subsequent phase 1 human study of subcutaneously administered CpG 7909. A single dose of clinical-grade CpG 7909 induced a rapid, sustained IP-10 response, a biomarker for activation of the innate immune system. Given the similar susceptibilities of humans and rhesus macaques to infectious diseases, the rhesus macaque appears to be a suitable model to evaluate the potential of CpG 7909-mediated innate immune activation to protect humans against pathogens.
Use of Commercial Enzyme Immunoassays To Detect Antibodies to the Herpes Simplex Virus Type 2 Glycoprotein G in a Low-Risk Population in Hanoi, Vietnam
Authors: Ngo Thoai D. , Laeyendecker Oliver , La Hanh , Hogrefe Wayne , Morrow Rhoda Ashley , Quinn Thomas C.
Published: December 2007

Sera from 1,238 Vietnamese women in Hanoi were tested for herpes simplex virus type 2 (HSV-2). HSV-2 prevalence was 2.0%. The Kalon and Biokit assays showed significantly higher concordance to Western blotting data than did the Focus assay (
P
< 0.01). Screening by Focus and then retesting with Kalon/Biokit of positive samples can reduce falsely positive results significantly (
P
< 0.01).
Cervical Human Papillomavirus (HPV) Infection and HPV Type 16 Antibodies in South African Women
Authors: Marais Dianne J. , Constant Debbie , Allan Bruce , Carrara Henri , Hoffman Margaret , Shapiro Samuel , Morroni Chelsea , Williamson Anna-Lise
Published: December 2007

There is a high incidence of cervical cancer in South African women. No large studies to assess human papillomavirus virus (HPV) infection or HPV type 16 (HPV-16) exposure have occurred in the region, a requirement for policy making with regards to HPV screening and the introduction of vaccines. Control women (n= 1,003) enrolled in a case control study of hormonal contraceptives and cervical cancer were tested for 27 cervical HPV types by reverse line blot analysis. The seroprevalence of HPV-16 immunoglobulin G (IgG) and IgA antibodies was assessed by a virus-like particle-based enzyme-linked immunoassay of 908 and 904 control women, respectively, and of 474 women with cervical cancer. The cervical HPV prevalence was 26.1%. The HPV-16 IgG seroprevalence was 44.4% and the HPV-16 IgA seroprevalence was 28.7% in control women, and these levels were significantly higher (61.8% and 52.7%, respectively) for women with cervical cancer (odds ratio [OR], 2.1 and 2.8, respectively). The cervical HPV prevalence showed an association with cervical disease, and the HPV-16 IgG prevalence decreased while the HPV-16 IgA prevalence increased with increasing age (P< 0.05). The prevalence of oncogenic HPV types (including HPV-16) decreased with age, whereas nononcogenic HPV types showed limited association with age. Multivariate analysis revealed cervical HPV infection to be associated with herpes simplex virus type 2 infection (OR, 1.7) and increasing years of education (OR, 1.9). HPV-16 IgG antibodies were inversely associated with current smoking status (OR, 0.6), and the presence of HPV-16 IgA antibodies was inversely associated with the use of alcohol (OR, 2.1) and inversely associated with the use of oral contraceptives (OR, 0.6). High levels of exposure to HPV, and particularly HPV-16, were evident in this population. The apparent increase of serum HPV-16 IgA with increasing age requires further investigation.
Treatment with Tigecycline of Recurrent Urosepsis Caused by Extended-Spectrum-β-Lactamase-Producing
Escherichia coli
Authors: Krueger Wolfgang A. , Kempf Volkhard A. J. , Peiffer Manou , Nagele Udo , Unertl Klaus E. , Schroeder Torsten H.
Published: December 2007

A 25-year-old female was admitted to our intensive care unit with septic shock and multiorgan failure caused by extended-spectrum β-lactamase-producing
Escherichia coli
originating from the right renal pelvis. A 16-day course of treatment with meropenem reversed the septic condition, but the infection recurred thereafter. The patient recovered fully after therapy was changed to tigecycline.
Pathotypical Characterization and Molecular Epidemiology of Newcastle Disease Virus Isolates from Different Hosts in China from 1996 to 2005
Authors: Qin Zhuo-Ming , Tan Lei-Tao , Xu Huai-Ying , Ma Bao-Chen , Wang You-Ling , Yuan Xiao-Yuan , Liu Wen-Jun
Published: December 2007

Thirty Newcastle disease virus (NDV) strains isolated from outbreaks in China during 1996 to 2005 were characterized pathotypically and genotypically. All strains except one were velogenic. An analysis of the variable region (nucleotides 47 to 420) of the F gene indicated that 6 isolates belonged to genotype II, 3 to genotype III, 1 (isolated from a pigeon) to genotype VI, and 20 to genotype VII. Isolates belonging to genotype VII were further divided into five subtypes, VIIa, VIIb, VIIc, VIId, and VIIe, and subtype VIId was made up of VIId1 to VIId5. These results showed that genotype VII isolates might have been the most prevalent in China during the past two decades. Genotype VII isolates shared high homology, but the homology was less than that between genotype VII viruses and the vaccine virus LaSota. Among these NDV isolates, 25 isolates had the velogenic motif
112
R/K-R-Q-K/R-R-F
117
that is consistent with results of the biological tests. However, four of five LaSota-type isolates that contained the lentogenic motif
112
G-R-Q-G-R-L
117
were velogenic, except SY/03, in the view of the biological test. The majority of genotype VII isolates had lost one or two N-glycosylation sites. Finally, a cross-protection experiment in which specific-pathogen-free chickens vaccinated with LaSota were challenged by six NDV isolates showed that more than three isolates were antigenic variants that could be responsible for recent outbreaks of Newcastle disease.
Discrimination of Herpes Simplex Virus Type 2 Strains by Nucleotide Sequence Variations
Authors: Kaneko Hisatoshi , Kawana Takashi , Ishioka Ken , Fukushima Eiko , Suzutani Tatsuo
Published: December 2007

We determined the polymorphous 400-bp regions in UL53, US1, and US4 for the discrimination of herpes simplex virus type 2 (HSV-2) strains. Thirty-six HSV-2 clinical strains could be differentiated into 35 groups using these three regions and into 36 groups by additional analysis of three noncoding regions previously reported as polymorphous.
Differences in Potential for Selection of Clindamycin-Resistant Mutants Between Inducible
erm
(A) and
erm
(C)
Staphylococcus aureus
Genes
Authors: Daurel Claire , Huet Corinne , Dhalluin Anne , Bes Michèle , Etienne Jerome , Leclercq Roland
Published: December 2007

In staphylococci, inducible macrolide-lincosamide-streptogramin B (MLS
B
) resistance is conferred by the
erm
(C) or
erm
(A) gene. This phenotype is characterized by the erythromycin-clindamycin “D-zone” test. Although clindamycin appears active in vitro, exposure of MLS
B
-inducible
Staphylococcus aureus
to this antibiotic may result in the selection of clindamycin-resistant mutants, either in vitro or in vivo. We have compared the frequencies of mutation to clindamycin resistance for 28 isolates of
S. aureus
inducibly resistant to erythromycin and bearing the
erm
(C) (
n
= 18) or
erm
(A) (
n
= 10) gene. Seven isolates susceptible to erythromycin or bearing the
msr
(A) gene (efflux) were used as controls. The frequencies of mutation to clindamycin resistance for the
erm
(A) isolates (mean ± standard deviation, 3.4 × 10
−8
± 2.4 × 10
−8
) were only slightly higher than those for the controls (1.1 × 10
−8
± 6.4 × 10
−9
). By contrast,
erm
(C) isolates displayed a mean frequency of mutation to clindamycin resistance (4.7 × 10
−7
± 5.5 × 10
−7
) 14-fold higher than that of the
S. aureus
isolates with
erm
(A). The difference was also observed, although to a lower extent, when
erm
(C) and
erm
(A) were cloned into
S. aureus
RN4220. We conclude that
erm
(C) and
erm
(A) have different genetic potentials for selection of clindamycin-resistant mutants. By the disk diffusion method,
erm
(C) and
erm
(A) isolates could be distinguished on the basis of high- and low-level resistance to oleandomycin, respectively.
Heterogeneity of Hemolysin Expression during Neonatal
Streptococcus agalactiae
Sepsis
Authors: Sigge Anja , Schmid Manuel , Mauerer Stefanie , Spellerberg Barbara
Published: December 2007

The β-hemolysin of
Streptococcus agalactiae
is a major virulence factor; consequently, nonhemolytic strains rarely cause infections. We report on a case of neonatal sepsis caused by a strain displaying heterogeneous hemolysin expression. It was detected by the simultaneous isolation of hemolytic and nonhemolytic colonies from cultures of the infant's blood.
Candida bracarensis
Detected among Isolates of
Candida glabrata
by Peptide Nucleic Acid Fluorescence In Situ Hybridization: Susceptibility Data and Documentation of Presumed Infection
Authors: Bishop Justin A. , Chase Nancy , Magill Shelley S. , Kurtzman Cletus P. , Fiandaca Mark J. , Merz William G.
Published: December 2007

Molecular taxonomic studies have revealed new
Candida
species among phenotypically delineated species, the best example being
Candida dubliniensis
. This study was designed to determine the occurrence of two new molecularly defined species,
Candida bracarensis
and
Candida nivariensis
, which are closely related to and identified as
Candida glabrata
by phenotypic assays. A total of 137 recent clinical isolates of
C. glabrata
identified by phenotypic characteristics was tested with
C. bracarensis
and
C. nivariensis
species-specific peptide nucleic acid fluorescence in situ hybridization probes. Three of 137 (2.2%) isolates were positive with the
C. bracarensis
probe, whereas the control strain, but none of the clinical isolates, was positive with the
C. nivariensis
probe. D1/D2 sequencing confirmed the identification of the three isolates as representing
C. bracarensis
. Clinically, one
C. bracarensis
isolate was recovered from a presumed infection, a polymicrobial pelvic abscess in a patient with perforated diverticulitis. The other two isolates were recovered from two adult oncology patients who were only colonized.
C. bracarensis
was white on CHROMagar Candida, had variable API-20C patterns that overlapped with
C. nivariensis
and some
C. glabrata
isolates, and had variable results with a rapid trehalose assay. Interestingly, an isolate from one of the colonized oncology patients was resistant to fluconazole, itraconazole, voriconazole, and posaconazole in vitro. In summary,
C. bracarensis
was detected among clinical isolates of
C. glabrata
, while
C. nivariensis
was not. One
C. bracarensis
isolate causing a presumed deep infection was recovered, and another isolate was azole resistant. Whether clinical laboratories should identify
C. bracarensis
will require more data.
Multiple Displacement Amplification Enables Large-Scale Clonal Analysis following Retroviral Gene Therapy
Authors: Bleier S. , Maier P. , Allgayer H. , Wenz F. , Zeller W. J. , Fruehauf S. , Laufs S.
Published: December 2007

Analysis of the fate of retrovirally transduced cells after transplantation is often hampered by the scarcity of available DNA. We evaluated a promising method for whole-genome amplification, called multiple displacement amplification (MDA), with respect to even and accurate representation of retrovirally transduced genomic DNA. We proved that MDA is a suitable method to subsequently quantify engraftment efficiencies by quantitative real-time PCR by analyzing retrovirally transduced DNA in a background of untransduced DNA and retroviral integrations found in primary material from a retroviral transplantation model. The portion of these retroviral integrations in the amplified samples was 1.02-fold (range 0.2, to 2.1-fold) the portion determined in the original genomic DNA. Integration site analysis by ligation-mediated PCR (LM-PCR) is essential for the detection of retroviral integrations. The combination of MDA and LM-PCR showed an increase in the sensitivity of integration site analysis, as a specific integration site could be detected in a background of untransduced DNA, while the transduced DNA made up only 0.001%. These results show for the first time that MDA enables large-scale sensitive detection and reliable quantification of retrovirally transduced human genomic DNA and therefore facilitates follow-up analysis in gene therapy studies even from the smallest amounts of starting material.
Structure of the Receptor-Binding Protein of Bacteriophage Det7: a Podoviral Tail Spike in a Myovirus
Authors: Walter Monika , Fiedler Christian , Grassl Renate , Biebl Manfred , Rachel Reinhard , Hermo-Parrado X. Lois , Llamas-Saiz Antonio L. , Seckler Robert , Miller Stefan , van Raaij Mark J.
Published: December 2007

A new
Salmonella enterica
phage, Det7, was isolated from sewage and shown by electron microscopy to belong to the
Myoviridae
morphogroup of bacteriophages. Det7 contains a 75-kDa protein with 50% overall sequence identity to the tail spike endorhamnosidase of podovirus P22. Adsorption of myoviruses to their bacterial hosts is normally mediated by long and short tail fibers attached to a contractile tail, whereas podoviruses do not contain fibers but attach to host cells through stubby tail spikes attached to a very short, noncontractile tail. The amino-terminal 150 residues of the Det7 protein lack homology to the P22 tail spike and are probably responsible for binding to the base plate of the myoviral tail. Det7 tail spike lacking this putative particle-binding domain was purified from
Escherichia coli
, and well-diffracting crystals of the protein were obtained. The structure, determined by molecular replacement and refined at a 1.6-Å resolution, is very similar to that of bacteriophage P22 tail spike. Fluorescence titrations with an octasaccharide suggest Det7 tail spike to bind its receptor lipopolysaccharide somewhat less tightly than the P22 tail spike. The Det7 tail spike is even more resistant to thermal unfolding than the already exceptionally stable homologue from P22. Folding and assembly of both trimeric proteins are equally temperature sensitive and equally slow. Despite the close structural, biochemical, and sequence similarities between both proteins, the Det7 tail spike lacks both carboxy-terminal cysteines previously proposed to form a transient disulfide during P22 tail spike assembly. Our data suggest receptor-binding module exchange between podoviruses and myoviruses in the course of bacteriophage evolution.
A Repetitive Region of Gammaherpesvirus Genomic DNA Is a Ligand for Induction of Type I Interferon
Authors: Sanchez David Jesse , Miranda Daniel , Arumugaswami Vaithilingaraja , Hwang Seungmin , Singer Adam E. , Senaati Ashkon , Shahangian Arash , Song Moon Jung , Sun Ren , Cheng Genhong
Published: December 2007

Innate immune responses against viral infection, especially the induction of type I interferon, are critical for limiting the replication of the virus. Although it has been shown that DNA can induce type I interferon, to date no natural DNA ligand of a virus that induces type I interferon has been described. Here we screened the genome of murine gammaherpesvirus 68 with mutations at various genomic locations to map the region of DNA that induces type I interferon. A repetitive region termed the 100-base-pair repeat region is a ligand that is both necessary and sufficient for the viral genomic DNA to induce type I interferon. A region colinear with this ligand in the genome of Kaposi's sarcoma-associated herpesvirus also induces type I interferon. We have thus defined a repetitive region of the genomes of gammaherpesviruses as the first natural DNA virus ligand that induces type I interferon.
Antiretroviral Activity of Ancestral TRIM5α
Authors: Goldschmidt Valérie , Ciuffi Angela , Ortiz Millan , Brawand David , Muñoz Miguel , Kaessmann Henrik , Telenti Amalio
Published: December 2007

The antiretroviral protein TRIM5α is known to have evolved different restriction capacities against various retroviruses, driven by positive Darwinian selection. However, how these different specificities have evolved in the primate lineages is not fully understood. Here we used ancestral protein resurrection to estimate the evolution of antiviral restriction specificities of TRIM5α on the primate lineage leading to humans. We used TRIM5α coding sequences from 24 primates for the reconstruction of ancestral
TRIM5α
sequences using maximum-likelihood and Bayesian approaches. Ancestral sequences were transduced into HeLa and CRFK cells. Stable cell lines were generated and used to test restriction of a panel of extant retroviruses (human immunodeficiency virus type 1 [HIV-1] and HIV-2, simian immunodeficiency virus [SIV] variants SIV
mac
and SIV
agm
, and murine leukemia virus [MLV] variants N-MLV and B-MLV). The resurrected TRIM5α variant from the common ancestor of Old World primates (Old World monkeys and apes, ∼25 million years before present) was effective against present day HIV-1. In contrast to the HIV-1 restriction pattern, we show that the restriction efficacy against other retroviruses, such as a murine oncoretrovirus (N-MLV), is higher for more recent resurrected hominoid variants. Ancestral TRIM5α variants have generally limited efficacy against HIV-2, SIV
agm
, and SIV
mac
. Our study sheds new light on the evolution of the intrinsic antiviral defense machinery and illustrates the utility of functional evolutionary reconstruction for characterizing recently emerged protein differences.
Global Transcriptional Responses of
Pseudomonas aeruginosa
to Phage PRR1 Infection
Authors: Ravantti Janne J. , Ruokoranta Tanja M. , Alapuranen A. Marika , Bamford Dennis H.
Published: December 2007

The infectious cycles of viruses are known to cause dramatic changes to host cell function. The development of microarray technology has provided means to monitor host cell responses to viral infection at the level of global changes in mRNA levels. We have applied this methodology to investigate gene expression changes caused by a small, icosahedral, single-stranded-RNA phage, PRR1 (a member of the
Leviviridae
family), on its host,
Pseudomonas aeruginosa
, at different times during its growth cycle. Viral infection in this system resulted in changes in expression levels of <4% of
P. aeruginosa
genes. Interestingly, the number of genes affected by viral infection was significantly lower than the number of genes affected by changes in growth conditions during the experiment. Compared with a similar study that focused on the complex, double-stranded-DNA bacterial virus PRD1, it was evident that there were no universal responses to viral infection. However, in both cases, translation was affected in infected cells.
The Essential Human Cytomegalovirus Gene UL52 Is Required for Cleavage-Packaging of the Viral Genome
Authors: Borst Eva Maria , Wagner Karen , Binz Anne , Sodeik Beate , Messerle Martin
Published: December 2007

Replication of human cytomegalovirus (HCMV) produces large DNA concatemers of head-to-tail-linked viral genomes that upon packaging into capsids are cut into unit-length genomes. The mechanisms underlying cleavage-packaging and the subsequent steps prior to nuclear egress of DNA-filled capsids are incompletely understood. The hitherto uncharacterized product of the essential HCMV UL52 gene was proposed to participate in these processes. To investigate the function of pUL52, we constructed a ΔUL52 mutant as well as a complementing cell line. We found that replication of viral DNA was not impaired in noncomplementing cells infected with the ΔUL52 virus, but viral concatemers remained uncleaved. Since the subnuclear localization of the known cleavage-packaging proteins pUL56, pUL89, and pUL104 was unchanged in ΔUL52-infected fibroblasts, pUL52 does not seem to act via these proteins. Electron microscopy studies revealed only B capsids in the nuclei of ΔUL52-infected cells, indicating that the mutant virus has a defect in encapsidation of viral DNA. Generation of recombinant HCMV genomes encoding epitope-tagged pUL52 versions showed that only the N-terminally tagged pUL52 supported viral growth, suggesting that the C terminus is crucial for its function. pUL52 was expressed as a 75-kDa protein with true late kinetics. It localized preferentially to the nuclei of infected cells and was found to enclose the replication compartments. Taken together, our results demonstrate an essential role for pUL52 in cleavage-packaging of HCMV DNA. Given its unique subnuclear localization, the function of pUL52 might be distinct from that of other cleavage-packaging proteins.
Cellular Determinants of Hepatitis C Virus Assembly, Maturation, Degradation, and Secretion
Authors: Gastaminza Pablo , Cheng Guofeng , Wieland Stefan , Zhong Jin , Liao Wei , Chisari Francis V.
Published: December 2007

Intracellular infectious hepatitis C virus (HCV) particles display a distinctly higher buoyant density than do secreted virus particles, suggesting that the characteristic low density of extracellular HCV particles is acquired during viral egress. We took advantage of this difference to examine the determinants of assembly, maturation, degradation, and egress of infectious HCV particles. The results demonstrate that HCV assembly and maturation occur in the endoplasmic reticulum (ER) and post-ER compartments, respectively, and that both depend on microsomal transfer protein and apolipoprotein B, in a manner that parallels the formation of very-low-density lipoproteins (VLDL). In addition, they illustrate that only low-density particles are efficiently secreted and that immature particles are actively degraded, in a proteasome-independent manner, in a post-ER compartment of the cell. These results suggest that by coopting the VLDL assembly, maturation, degradation, and secretory machinery of the cell, HCV acquires its hepatocyte tropism and, by mimicry, its tendency to persist.
H5-Type Influenza Virus Hemagglutinin Is Functionally Recognized by the Natural Killer-Activating Receptor NKp44
Authors: Ho Joanna W. , Hershkovitz Oren , Peiris Malik , Zilka Alon , Bar-Ilan Ahuva , Nal Beatrice , Chu Kid , Kudelko Mateusz , Kam Yiu Wing , Achdout Hagit , Mandelboim Michal , Altmeyer Ralf , Mandelboim Ofer , Bruzzone Roberto , Porgador Angel
Published: December 2007

Antiviral immune defenses involve natural killer (NK) cells. We previously showed that the NK-activating receptor NKp44 is involved in the functional recognition of H1-type influenza virus strains by NK cells. In the present study, we investigated the interaction of NKp44 and the hemagglutinin of a primary influenza virus H5N1 isolate. Here we show that recombinant NKp44 recognizes H5-expressing cells and specifically interacts with soluble H5 hemagglutinin. H5-pseudotyped lentiviral particles bind to NK cells expressing NKp44. Following interaction with target cells expressing H5, pseudotyped lentiviral particles, or membrane-associated H5, NK cells show NKp44-mediated induced activity. These findings indicate that NKp44-H5 interactions induce functional NK activation.
Hepatitis C Virus Genotype 1a Growth and Induction of Autophagy
Authors: Ait-Goughoulte Malika , Kanda Tatsuo , Meyer Keith , Ryerse Jan S. , Ray Ratna B. , Ray Ranjit
Published: December 2007

We have previously reported that immortalized human hepatocytes (IHH) support the generation of infectious hepatitis C virus (HCV) genotype 1a (clone H77). In the present study, we have investigated the growth of HCV genotype 1a (clone H77) through serial passages and accompanying changes in IHH in response to infection. Eleven serial passages of HCV genotype 1a (clone H77) in IHH were completed. Virus replication was ascertained from the presence of HCV-specific sequences, the detection of core antigen, the virus genome copy number, and the virus titer in IHH culture fluid. Electron microscopy suggested that HCV infection induces autophagic vacuole formation in IHH. Fluorescence microscopy displayed localization of autophagic markers, microtubule-associated protein-1 light chain-3 and Apg5, on the vacuoles of HCV-infected hepatocytes. Taken together, our results suggested that HCV genotype 1a (clone H77) can be serially passaged in IHH and that HCV infection induces an autophagic response in hepatocytes.
Variable Transcriptional Activity of Endogenous Retroviruses in Human Breast Cancer
Authors: Frank Oliver , Verbeke Caroline , Schwarz Norbert , Mayer Jens , Fabarius Alice , Hehlmann Rüdiger , Leib-Mösch Christine , Seifarth Wolfgang
Published: December 2007

Human endogenous retroviruses (HERVs) account for up to 9% of the human genome and include more than 800 elements related to betaretroviruses. While mouse mammary tumor virus (MMTV) is the accepted etiological agent of mammary tumors in mice, the role of retroviral elements in human breast cancer remains elusive. Here, we performed a comprehensive microarray-based analysis of overall retroviral transcriptional activities in 46 mammary gland tissue specimens representing pairs of nonmalignant and tumor samples from 23 patients. An analysis of nonmalignant tissue samples revealed a distinct, mammary gland-specific HERV expression profile that consists of 18 constitutively active HERV taxa. For corresponding tumor samples, a general trend toward lower levels of HERV transcription was observed, suggesting common regulatory mechanisms. In various subsets of patients, however, increased transcript levels of single class I HERV families (HERV-T, HERV-E, and HERV-F) and several class II families, including HML-6, were detected. An analysis of transcribed HML-6 sequences revealed either the activation of some or the increased activity of several proviral loci. No evidence for MMTV or human MMTV-like virus transcripts was found, indicating that transcriptionally active, MMTV analogous, exogenous viruses were not present in the breast cancer samples analyzed.
Chronic CD4+T-Cell Activation and Depletion in Human Immunodeficiency Virus Type 1 Infection: Type I Interferon-Mediated Disruption of T-Cell Dynamics
Authors: Sedaghat Ahmad R. , German Jennifer , Teslovich Tanya M. , Cofrancesco Joseph , Jie Chunfa C. , Talbot C. Conover , Siliciano Robert F.
Published: December 2007

The mechanism of CD4+T-cell depletion during chronic human immunodeficiency virus type 1 (HIV-1) infection remains unknown. Many studies suggest a significant role for chronic CD4+T-cell activation. We assumed that the pathogenic process of excessive CD4+T-cell activation would be reflected in the transcriptional profiles of activated CD4+T cells. Here we demonstrate that the transcriptional programs of in vivo-activated CD4+T cells from untreated HIV-positive (HIV+) individuals are clearly different from those of activated CD4+T cells from HIV-negative (HIV−) individuals. We observed a dramatic up-regulation of cell cycle-associated and interferon-stimulated transcripts in activated CD4+T cells of untreated HIV+individuals. Furthermore, we find an enrichment of proliferative and type I interferon-responsive transcription factor binding sites in the promoters of genes that are differentially expressed in activated CD4+T cells of untreated HIV+individuals compared to those of HIV−individuals. We confirm these findings by examination of in vivo-activated CD4+T cells. Taken together, these results suggest that activated CD4+T cells from untreated HIV+individuals are in a hyperproliferative state that is modulated by type I interferons. From these results, we propose a new model for CD4+T-cell depletion during chronic HIV-1 infection.
Coronavirus Escape from Heptad Repeat 2 (HR2)-Derived Peptide Entry Inhibition as a Result of Mutations in the HR1 Domain of the Spike Fusion Protein
Authors: Bosch Berend Jan , Rossen John W. A. , Bartelink Willem , Zuurveen Stephanie J. , de Haan Cornelis A. M. , Duquerroy Stephane , Boucher Charles A. B. , Rottier Peter J. M.
Published: December 2007

Peptides based on heptad repeat (HR) domains of class I viral fusion proteins are considered promising antiviral drugs targeting virus cell entry. We have analyzed the evolution of the mouse hepatitis coronavirus during multiple passaging in the presence of an HR2-based fusion inhibitor. Drug-resistant variants emerged as a result of multiple substitutions in the spike fusion protein, notably within a 19-residue segment of the HR1 region. Strikingly, one mutation, an A1006V substitution, which consistently appeared first in four independently passaged viruses, was the main determinant of the resistance phenotype, suggesting that only limited options exist for escape from the inhibitory effect of the HR2 peptide.
Genome Organization and Reverse Genetic Analysis of a Type I Feline Coronavirus
Authors: Tekes Gergely , Hofmann-Lehmann Regina , Stallkamp Iris , Thiel Volker , Thiel Heinz-Jürgen
Published: December 2007

In this study we report the complete sequence and genome organization of the serotype I feline coronavirus (FCoV) strain Black. Furthermore, a reverse genetic system was established for this FCoV strain by cloning a full-length cDNA copy into vaccinia virus. This clone served as basis for the generation of recombinant FCoV (recFCoV) that was shown to bear the same features in vitro as the parental FCoV. Using this system, accessory 3abc genes in the FCoV genome were replaced by green fluorescent protein (recFCoV-GFP) andRenillaluciferase genes (recFCoV-RL). In addition, we showed that feline CD14+blood monocytes and dendritic cells can be easily detected after infection with recFCoV-GFP. Thus, our established reverse genetic system provides a suitable tool to study the molecular biology of serotype I FCoV.
An electron microscopic study of meiosis and the spindle pole body cycle in the smut fungus Sphacelotheca polygoni-serrulati
Authors: Bauer Robert , Berbee Mary L. , Oberwinkler Franz
Published: December 2007

An electron microscopic study was made of meiosis and the meiotic spindle pole body (SPB) cycle in germinating teliospores of the smut fungus Sphacelotheca polygoni-serrulati. SPB development in prophase I and duplication in interphase I were studied in detail. During prophase, the globular elements of the biglobular SPB enlarged, became oblate in form, developed internal layering, and became associated with astral microtubules. The middle piece decreased in size and finally disappeared. Prior to metaphase I, the two oblate elements moved apart along the intact surface of the nuclear envelope, and the nuclear membrane bulged into the space between the two SPBs. Metaphase I – early telophase I and metaphase II – early telophase II SPBs were intranuclear, oblate spheroidal in shape, and traversed by an electron-dense disc. In interphase I, an electron-dense bar appeared in association with the nuclear side of the original SPB. The bar initially overlapped one edge of the electron-dense disc and later appeared at the side of the disc. The bar became one of the metaphase II SPBs. Similarities and differences between meiosis and SPBs in Sphacelotheca polygoni-serrulati, Ustilago maydis, Ustilago esculenta, Tilletia foetida, and other heterobasidiomycetes are discussed. Key words: heterobasidiomycetes, Ustilaginales, Sphacelotheca, meiosis, spindle pole body, ultrastructure.
A multivariate morphometric study and revision of Aster subg. Doellingeria sect. Triplopappus (Compositae: Astereae): the Aster umbellatus complex
Authors: Semple John C. , Chmielewski Jerry G. , Leeder Colleen
Published: December 2007

A multivariate morphometric study of Aster subg. Doellingeria sect. Triplopappus (Compositae: Astereae) was undertaken to assess the numbers and ranks of taxa that usefully could be recognized. The results of cluster, discriminant, and principal components analyses on a matrix of 362 plants by 11 characters indicated that four species level groups can be recognized: Aster inflrmus, A. reticulatus, A. sericocarpoides, and A. umbellatus. Within A. umbellatus, analyses of a 12-character data matrix on an additional 140 plants and analysis of a second matrix consisting of the data on the 198 plants of the species included in the species-level study supported recognition of two varieties: pubens and umbellatus. The qualitative and quantitative differences between the two varieties were smaller than those among the four species. Using a key to the taxa produced from all results, the distributions of the four species and two varieties were determined from a large sample of herbarium specimens and a nomenclatural synonymy was developed. Some lectotypes and a neotype are designated. All taxa in the section are diploid 2n = 18; chromosome numbers for 42 individuals of A. umbellatus are reported for the first time. Key words: Aster, Doellingeria, Triplopappus, multivariate morphometric study, Aster umbellatus, key.
Isoetes prototypus, a new diploid species from eastern Canada
Authors: Britton D. M. , Goltz J. P.
Published: December 2007

A new species of Isoetes, I. prototypus from eastern Canada, is described. The morphology of the megaspores shows some similarity to those of acadiensis and I. hieroglyphica, but the microspores have a spinulose network on their surface. The plants have straight and rigid leaves that resemble some forms of I. macrospora. The species is diploid (2n = 22) and is found deep (± 2 m) in cool lakes in New Brunswick and Nova Scotia. Key words: Isoetes, new species, diploid, Canada, SEM.
Apple tree canopy development and photosynthesis as affected by rootstock
Authors: Schechter Ido , Elfving D. C. , Proctor J. T. A.
Published: December 2007

Trees of apple (Malus domestica Borkh.) with 'Starkspur Supreme Delicious' as the scion grafted on nine different rootstocks (Ottawa 3, M.7 EMLA, M.9 EMLA, M.26 EMLA, M.27 EMLA, M.9, MAC-9, MAC-24, OAR 1) were studied in their 8th and 9th years. Canopy seasonal development and its light interception followed by fisheye (hemispherical) photography showed that rootstock affected the amount of structural wood, the rate of canopy development, and final leaf area. However, rootstock did not affect the sigmoidal pattern of canopy development. Light interception was linearly correlated with tree dimensions and yield. Leaf net photosynthesis (Pn) of trees on dwarfing rootstocks tended to be lower than Pn rates of trees on more vigorous rootstocks. Rootstock did not affect the scion Pn response to different illumination levels. Shoot leaves, spur leaves on spurs without fruit (S − F), and spur leaves on spurs with fruit (S + F) from trees on M.26 EMLA and OAR 1 showed no differences in Pn rates. However, for both rootstocks, shoot leaves had the highest Pn rate, S + F the lowest, and S − F leaves had intermediate values. Key words: light interception, fisheye photography, leaf type.
Lodgepole pine seed germination. III. Patterns of protein and nucleic acid synthesis in the megagametophyte and embryo
Authors: Gifford David J. , Dale Phyllis L. , Wenzel Kevin A.
Published: December 2007

A study of lodgepole pine (Pinus contorta Dougl.) seeds following imbibition at 28 °C has shown that in the megagametophyte, RNA and DNA levels remained constant until 5 days after imbibition when a decrease occurred. In the embryo, increases in RNA and DNA occurred 2 and 5 days after imbibition, respectively. Incorporation of [3H]uridine into total RNA was maximum by 2 days after imbibition in both the megagametophyte and the embryo. Incorporation of [3H]leucine into buffer-soluble protein showed a similar trend for both organs except that maximum incorporation occurred by 3 days after imbibition. An electrophoretic analysis of buffer-soluble proteins synthesized following the incorporation of [35S]methionine showed similar patterns for both the megagametophyte and the embryo. In both organs, the synthesis of three subsets of proteins was recognized. One subset was synthesized in the mature seed. Synthesis continued through germination but was terminated prior to radicle emergence. Synthesis of a second subset coincided with radicle emergence and continued during early seedling growth. A third subset was synthesized constitutively throughout germination and early seedling growth. Keywords: nucleic acid synthesis, protein synthesis, seed germination, lodgepole pine.
The role of fosetyl-Al in the potential integrated control of Fulvia fulva
Authors: Tirilly Yves
Published: December 2007

Fulvia fulva, the agent of leaf mould, is known to be a major parasite of tomato leaves in greenhouses. Its development is characterized by a biotrophic phase followed by a necrotrophic phase. Hansfordia pulvinata is a hyperparasite of this pathogen, but its destructive action is restricted by its inability to colonize F. fulva during the biotrophic phase, before lesion formation. An integrated system to optimize the mycoparasitic activity of H. pulvinata was studied. The hyperparasite was tolerant to fosetyl-Al in situ. At a minimal concentration of 500 mg/L, the fungicide inhibited F. fulva spore germination after spraying on tomato leaves but did not have any effect during the necrotrophic phase. Thus, fosetyl-Al, which prevented reinfection, and the destructive hyperparasite H. pulvinata had complementary effects. Key words: Hansfordia pulvinata, fosetyl-Al, Fulvia fulva, integrated control, leaf mould, tomato.
Étude des variations de radiosensibilité des semences d'orge (Hordeum vulgare) en fonction de la teneur en eau
Authors: Arabi M. I. , Barrault G. , Sarrafi A. , Albertini L.
Published: December 2007

The study of the sorption curve representing the development of water content versus relative humidity, in barley seeds (cv. Thibaut), shows that water is present in three different states: constitutive water at less than 8.1%, absorption water between 8.1 and 10.9%, and free water at more than 10.9%. Along with these water states, radiosensitivity is respectively high, low, and high. The seeds detached from the rachis have less radioresistance than the attached ones. However this difference in behaviour is reduced when the water content is high (presence of free water). We also observed that growth was stimulated by weak doses of irradiation (20 Gy), whatever the water content. Key words: barley, Hordeum vulgare, radiosensitivity, water content, seeds, rachis.
Modeling nonexponential growth of a short-cycling plant, Tagetes erecta (Asteraceae)
Authors: Russin W. A. , Clayton M. K. , Durbin R. D.
Published: December 2007

A method for establishing a plastochron index was developed as part of an analysis of the growth pattern of Tagetes erecta 'Moonshot' plants. Both log-linear and log-quadratic equations were fitted to balanced sets of leaf-length data. Although the log-linear model fit the data, the log-quadratic model consistently provided a better fit. Slope values and length of plastochron from both models were compared versus leaf and plant number. An analysis of variance showed that overall, the leaves grew at different rates and were initiated at different intervals. However, leaves 2–4 on each plant fulfilled the criteria for establishment of a leaf plastochron index and can be considered developmentally equivalent. The method presented herein is not only statistically appropriate but also most accurately represents growth of T. erecta. This method also should be useful where development of a plastochron index for rapidly growing plants is desired, and it may be applicable to plant growth studies in general. Key words: marigold, plastochron index, log-quadratic model.
Phosphate-solubilizing activity of ectomycorrhizal fungi in vitro
Authors: Lapeyrie F. , Ranger J. , Vairelles D.
Published: December 2007

An easy to use method is presented here to compare and study the mineral phosphate-solubilizing activity of ectomycorrhizal fungi. This technique can discriminate between strains with differing phosphate-solubilizing activities. Synthetic mineral phosphates, crystalline or amorphous, were differentially solubilized by 10 ectomycorrhizal fungi. Natural crystalline phosphates studied do not seem to be solubilized by fungi under similar experimental conditions. Paxillus involutus 1 appears to be able to solubilize calcium phosphates using either ammonium or nitrate nitrogen, but the other isolates were able to effectively solubilize phosphate only in the presence of ammonium. This has implications regarding the possible mechanism used to solubilize phosphate by these isolates. Recrystallization can be seen in the culture medium if calcium ions are present. The type of crystals depends on the phosphate source and on the fungal strain. This technique is suitable for screening a large number of ectomycorrhizal strains. The significance of phosphate-solubilizing activity to plant growth stimulation needs to be determined by field trials. Key words: ectomycorrhizal fungus, phosphate, solubilization.
Endophytic fungi from the mycorrhizae of alpine ericoid plants
Authors: Stoyke Godo , Currah R. S.
Published: December 2007

Strains of a slow-growing, sterile, darkly pigmented fungus were obtained from alpine mycorrhizae of the Alberta Rocky Mountains. Sporulating isolates of this fungus from the roots of Cassiope mertensiana and Arctostaphylos uva-ursi (Ericaceae) as well as from Luetkea pectinata (Rosaceae) were identified as Phialocephala fortinii. Axenic cultures of Menziesia ferruginea (Ericaceae) seedlings were grown with P. fortinii for characterization of the fungus–root association. Typically, dark, simple septate hyphae form extensive wefts on the root surface and produce intracortical sclerotia of compact, darkly pigmented and irregularly lobed, thick-walled hyphae. Intracellular coils are not produced. This association differs from the ericoid mycorrhizal type and represents a fungus–root association that is common in alpine plants. In addition, several isolates of Oidiodendron griseum, a species previously reported from mycorrhizae of ericaceous plants, were found to form intracellular coils within the cortical root cells of Loiseleuria procumbens (Ericaceae). Key words: alpine mycorrhizae, Ericaceae, Phialocephala fortinii, Oidiodendron griseum.
Modelling the phytotoxicity of aluminum, cadmium, copper, manganese, nickel, and zinc using the Weibull frequency distribution
Authors: Taylor Gregory J. , Stadt Kenneth J. , Dale Mark R. T.
Published: December 2007

The toxic effects of aluminum, cadmium, copper, manganese, nickel, and zinc stress on root growth of Triticum aestivum were modelled using a modified version of the Weibull frequency distribution. The modified Weibull function is a continuous, nonlinear mathematical function that provides direct estimates of several important biological parameters, including maximum growth, minimum growth, growth response, toxicity threshold, and maximum unit toxicity. The function was fit to experimental data using standard nonlinear regression techniques. Despite variation among metals in the characteristics of observed dose responses, the Weibull function provided a close fit for each of the metals tested (0.96 ≤ R2 ≤ 0.99). Estimates of maximum unit toxicities indicated that cadmium was most toxic to T. aestivum (152% growth reduction (GR)/(μmol∙L)), followed by copper (19.0% GR/(μmol∙L)), nickel (3.9% GR/(μmol∙L)), aluminum (1.3% GR/(μmol∙L)), zinc (0.5% GR/(μmol∙L)), and manganese (0.2% GR/((μmol∙L)). Estimated toxicity thresholds also indicated that cadmium was most toxic. Cadmium showed the lowest threshold for metal injury (0.02 μM), followed by copper (3.4 μM), nickel (11 μM), aluminum (18 μM), manganese (37 μM), and zinc (45 μM). The shift in the relative position of Mn and Zn suggests that unit toxicity and the toxicity threshold may be independent measures of the response of plants to metal stress. These experiments clearly demonstrate the utility of the Weibull function in modelling the response of plants to metal stress. Furthermore, the ability of the function to model primary growth data directly provides a suitable technique for investigation of potential interactions between phytotoxic metals. Key words: dose response, modelling, metal stress, toxicity threshold, unit toxicity.
Effects of Hebeloma arenosa and phosphorus fertility on growth of red pine (Pinus resinosa) seedlings
Authors: MacFall Janet , Slack Steven A. , Iyer Jaya
Published: December 2007

Red pine seedlings (Pinus resinosa Ait.) were grown in a pasteurized Sparta loamy fine sand (8–12 ppm P) amended with five levels (0, 17, 34, 68, or 136 mg/kg P) of added superphosphate. Trees for each fertility treatment were grown in containers for 19 weeks with and without addition of Hebeloma arenosa inoculum to soil. In P-unamended soil, all inoculated trees formed abundant mycorrhizae and had 12 times the root and 8 times the shoot dry weights of nonmycorrhizal trees. Degree of fungal colonization and growth enhancement decreased with increased P additions to soil. In soil with the highest level of added P, mycorrhizal colonization and growth promotion effects were not observed. Seedling tissue concentrations of P and K were increased with fungal colonization. Iron was preferentially accumulated in the roots of mycorrhizal trees, with reduced translocation to shoots. In P-unamended soil, nonmycorrhizal plants had greater concentrations of Cu, B, Na, and Co compared with either mycorrhizal seedlings or plants grown in P-amended soil. Key words: ectomycorrhizae, roots, plant nutrition.
Life history and population dynamics of Hordeum jubatum along a soil salinity gradient
Authors: Badger Kemuel S. , Ungar Irwin A.
Published: December 2007

This study examined the importance of the timing of germination and of seedling survival in determining the distribution of Hordeum jubatum along a soil salinity gradient. Survival and reproduction of mature plants were also observed over a 3-year period. Field observations indicated that seedling survival did not limit the distribution of H. jubatum except under unusually dry conditions. Seedlings were long-lived and persisted at salinities unfavorable for growth and reproduction. The two germination cohorts of H. jubatum are important in maintaining populations in the unpredictable environment of inland salt marshes. Salinity stress increased over the study period because of abnormally dry conditions and resulted in a shift in the distribution of H. jubatum along a topographic gradient. There was greater seed production per inflorescence with an increase in soil salinity. At different points along the salinity gradient, H. jubatum behaved as an annual, a short-lived perennial, and a long-lived perennial. Key words: Hordeum jubatum, survival, population dynamics, salt marsh, halophyte, seed production.