bluuebunny/crossref_metadata_2025 huggingface dataset:
Older Rhesus Macaque Infants Are More Susceptible to Oral Infection with Simian-Human Immunodeficiency Virus 89.6P than Neonates
Authors: Chenine Agnès-Laurence , Ferrantelli Flavia , Hofmann-Lehmann Regina , Vangel Mark G. , McClure Harold M. , Ruprecht Ruth M.
Published: December 2004

Earlier primate studies revealed that oral transmission of immunodeficiency viruses can occur at all ages [R. M. Ruprecht et al., J. Infect. Dis.179(Suppl. 3):S408-S412, 1999]. Using a stock of pathogenic simian-human immunodeficiency virus, SHIV89.6P, we compared the 50% animal infectious dose needed to achieve systemic infection after oral challenge in newborn and older infant or juvenile rhesus macaques. Unexpectedly, the older monkeys required a 150-fold-lower virus challenge dose than the neonates (P= 3.3 × 10−5). In addition, at least 60,000 times more virus was needed to achieve systemic infection in neonates by the oral route than by the intravenous route (P< 1 × 10−5). Thus, route of inoculation and age are important determinants of SHIV89.6P infectivity in rhesus macaques.
Analysis of Pigtail Macaque Major Histocompatibility Complex Class I Molecules Presenting Immunodominant Simian Immunodeficiency Virus Epitopes
Authors: Smith Miranda Z. , Dale C. Jane , De Rose Robert , Stratov Ivan , Fernandez Caroline S. , Brooks Andrew G. , Weinfurter Jason , Krebs Kendall , Riek Cara , Watkins David I. , O'Connor David H. , Kent Stephen J.
Published: December 2004

Successful human immunodeficiency virus (HIV) vaccines will need to induce effective T-cell immunity. We studied immunodominant simian immunodeficiency virus (SIV) Gag-specific T-cell responses and their restricting major histocompatibility complex (MHC) class I alleles in pigtail macaques (Macaca nemestrina), an increasingly common primate model for the study of HIV infection of humans. CD8+T-cell responses to an SIV epitope, Gag164-172KP9, were present in at least 15 of 36 outbred pigtail macaques. The immunodominant KP9-specific response accounted for the majority (mean, 63%) of the SIV Gag response. Sequencing from six macaques identified 7 newMane-Aand 13 newMane-BMHC class I alleles. One new allele,Mane-A*10, was common to four macaques that responded to the KP9 epitope. We adapted reference strand-mediated conformational analysis (RSCA) to MHC class I genotypeM. nemestrina. Mane-A*10was detected in macaques presenting KP9 studied by RSCA but was absent from non-KP9-presenting macaques. Expressed on class I-deficient cells, Mane-A*10, but not other pigtail macaque MHC class I molecules, efficiently presented KP9 to responder T cells, confirming thatMane-A*10restricts the KP9 epitope. Importantly, naïve pigtail macaques infected with SIVmac251that respond to KP9 had significantly reduced plasma SIV viral levels (log100.87 copies/ml;P= 0.025) compared to those of macaques not responding to KP9. The identification of this commonM. nemestrinaMHC class I allele restricting a functionally important immunodominant SIV Gag epitope establishes a basis for studying CD8+T-cell responses against AIDS in an important, widely available nonhuman primate species.
The Epstein-Barr Virus Protein BMRF1 Activates Gastrin Transcription
Authors: Holley-Guthrie Elizabeth A. , Seaman William T. , Bhende Prasanna , Merchant Juanita L. , Kenney Shannon C.
Published: December 2004

The Epstein-Barr virus (EBV) BMRF1 gene encodes an early lytic protein that functions not only as the viral DNA polymerase processivity factor but also as a transcriptional activator. BMRF1 has been previously shown to activate transcription of an EBV early promoter, BHLF1, though a GC-rich motif which binds to SP1 and ZBP-89, although the exact mechanism for this effect is not known (D. J. Law, S. A. Tarle, and J. L. Merchant, Mamm. Genome 9:165-167, 1998). Here we demonstrate that BMRF1 activates transcription of the cellular gastrin gene in telomerase-immortalized keratinocytes. Furthermore, BMRF1 activated a reporter gene construct driven by the gastrin promoter in a variety of cell types, and this effect was mediated by two SP1/ZBP-89 binding sites in the gastrin promoter. ZBP-89 has been previously shown to negatively regulate the gastrin promoter. However, ZBP-89 can function as either a negative or positive regulator of transcription, depending upon the promoter and perhaps other, as-yet-unidentified factors. BMRF1 increased the binding of ZBP-89 to the gastrin promoter, and a ZBP-89-GAL4 fusion protein was converted into a positive transcriptional regulator by cotransfection with BMRF1. BMRF1 also enhanced the transcriptional activity of an SP1-GAL4 fusion protein. These results suggest that BMRF1 activates target promoters through its effect on both the SP1 and ZBP-89 transcription factors. Furthermore, as the EBV genome is present in up to 10% of gastric cancers, and the different forms of gastrin are growth factors for gastrointestinal epithelium, our results suggest a mechanism by which lytic EBV infection could promote the growth of gastric cells.
Efficient Functional Pseudotyping of Oncoretroviral and Lentiviral Vectors by Venezuelan Equine Encephalitis Virus Envelope Proteins
Authors: Kolokoltsov Andrey A. , Weaver Scott C. , Davey Robert A.
Published: December 2004

Murine oncoretroviruses and lentiviruses pseudotyped with envelope proteins of alphaviruses have shown great potential in providing broad-host-range, stable vectors for gene therapy. Unlike vesicular stomatitis virus G protein-pseudotyped vectors, they are not neutralized by complement and do not appear to cause significant tissue damage. Here we report the production of murine oncoretroviral and lentiviral vectors pseudotyped with the envelope proteins of Venezuelan equine encephalitis virus (VEEV). When optimized, these pseudotypes achieve titers of 106CFU/ml, which is 5- to 10-fold higher than for previous vectors pseudotyped with envelope proteins from other alphaviruses. They can also be concentrated or stored frozen without significant loss of infectivity. Consistent with the tropism of the envelope donor, they transduce a broad array of human cell types, including lung epithelial cells, neuronal cells, lymphocytes, and fibroblasts. Infection is blocked by agents that inhibit endosomal acidification and by neutralizing antibodies against VEEV. These observations indicate that the pseudotypes present native epitopes on their surface and enter through a VEEV envelope-dependent, pH-sensitive mechanism. The fact that the pseudotypes are unaffected by sera reactive to other alphaviruses indicates that they may be useful when successive gene therapies are required in the presence of an active immune response. In this case, having an array of alphavirus-based vectors with similar cell tropisms would be highly advantageous. These vectors may also be useful in diagnostic assays in which infectious VEEV is undesirable but immune reactivity to native epitopes is required.
Mutations Conferring Resistance to Human Immunodeficiency Virus Type 1 Fusion Inhibitors Are Restricted by gp41 and Rev-Responsive Element Functions
Authors: Nameki Daisuke , Kodama Eiichi , Ikeuchi Mieko , Mabuchi Naoto , Otaka Akira , Tamamura Hirokazu , Ohno Mutsuhito , Fujii Nobutaka , Matsuoka Masao
Published: December 2004

One of the human immunodeficiency virus (HIV) envelope proteins, gp41, plays a key role in HIV fusion. A gp41-derived peptide, T-20, efficiently inhibits HIV fusion and is currently approved for treatment of HIV-infected individuals. Although resistant variants have been reported, the mechanism of the resistance remains to be defined. To elucidate the mechanism in detail, we generated variants resistant to C34, a peptide derived from the gp41 carboxyl terminus heptad repeat (C-HR) in vitro. The resistant variants had a 5-amino-acid deletion in gp120 and a total of seven amino acid substitutions in gp41. Binding assays revealed that an I37K substitution in the N-terminal heptad repeat (N-HR) impaired the binding of C34, whereas an N126K substitution in the C-HR enhanced the binding to mutated N-HR, indicating that both mutations were directly involved in resistance. On the other hand, substitutions for A30 and D36 seemed to be secondary mutations, located complementary to each other in the Rev-responsive element (RRE), and were mutated simultaneously to maintain the secondary structure of the RRE that was impaired by the mutations at I37. Thus, HIV acquired resistance to C34 by mutations in N-HR, which directly interacted with C34. However, since this region also encoded the RRE, additional mutations were required to maintain viral replication. These results suggest that HIV fusion is one of the attractive targets for HIV chemotherapy.
Antibodies That Are Cross-Reactive for Human Immunodeficiency Virus Type 1 Clade A and Clade B V3 Domains Are Common in Patient Sera from Cameroon, but Their Neutralization Activity Is Usually Restricted by Epitope Masking
Authors: Krachmarov Chavdar , Pinter Abraham , Honnen William J. , Gorny Miroslaw K. , Nyambi Phillipe N. , Zolla-Pazner Susan , Kayman Samuel C.
Published: December 2004

Sera from human immunodeficiency virus type 1 (HIV-1)-infected North American patients recognized a fusion protein expressing a V3 loop from a clade B primary isolate virus (JR-CSF) but not from a clade A primary isolate virus (92UG037.8), while most sera from Cameroonian patients recognized both fusion proteins. Competition studies of consensus V3 peptides demonstrated that the majority of the cross-reactive Cameroonian sera contained cross-reactive antibodies that reacted strongly with both V3 sequences. V3-specific antibodies purified from all six cross-reactive sera examined had potent neutralizing activity for virus pseudotyped with envelope proteins (Env) from SF162, a neutralization-sensitive clade B primary isolate. For four of these samples, neutralization of SF162 pseudotypes was blocked by both the clade A and clade B V3 fusion proteins, indicating that this activity was mediated by cross-reactive antibodies. In contrast, the V3-reactive antibodies from only one of these six sera had significant neutralizing activity against viruses pseudotyped with Envs from typically resistant clade B (JR-FL) or clade A (92UG037.8) primary isolates. However, the V3-reactive antibodies from these cross-reactive Cameroonian sera did neutralize virus pseudotyped with chimeric Envs containing the 92UG037.8 or JR-FL V3 sequence in Env backbones that did not express V1/V2 domain masking of V3 epitopes. These data indicated that Cameroonian sera frequently contain cross-clade reactive V3-directed antibodies and indicated that the typical inability of such antibodies to neutralize typical, resistant primary isolate Env pseudotypes was primarily due to indirect masking effects rather than to the absence of the target epitopes.
Engineering Glycoprotein B of Bovine Herpesvirus 1 To Function as Transporter for Secreted Proteins: a New Protein Expression Approach
Authors: Keil Günther M. , Höhle Constanze , Giesow Katrin , König Patricia
Published: December 2004

Glycoprotein B (gB) of bovine herpesvirus 1 (BHV-1) is essential for BHV-1 replication and is required for membrane fusion processes leading to virus penetration into the target cell and direct spreading of BHV-1 from infected to adjacent noninfected cells. Like many of the herpesvirus gB homologs, BHV-1 gB is proteolytically processed by furin, an endoproteinase localized in the
trans
-Golgi network. Cleavage by furin is a common mechanism for the activation of a number of viral fusion (F) proteins. Among these, the F proteins of both human and bovine respiratory syncytial virus (RSV) have the so-far unique feature that cleavage of the respective F protein precursors occurs at two furin recognition sites, resulting in the release of a 27-amino-acid intervening peptide which is secreted into the extracellular space. We showed recently that the intervening peptide of bovine RSV can be replaced by bovine interleukins which are secreted into the medium of cells infected with the respective bovine RSV recombinants (P. König, K. Giesow, K. Schuldt, U. J. Buchholz, and G. M. Keil, J. Gen. Virol. 85:1815-1824, 2004). To elucidate whether the approach to transport heterologous proteins as furin-excisable polypeptides functions in principle also in glycoproteins which are cleaved by furin only once, we inserted a second furin cleavage site into BHV-1 gB and integrated a 16-amino-acid peptide sequence, the 246-amino-acid green fluorescent protein (GFP), or the 167 amino acids for mature bovine alpha interferon (boIFN-α) as an intervening polypeptide. The resulting gB variants rescued gB-negative BHV-1 mutants, the resulting BHV-1 recombinants were fully infectious, and infected cells secreted biologically active GFP and boIFN-α, respectively. In contrast to the gB2Fu and gB2FuGFP precursor molecules, which were efficiently cleaved at both furin sites, the majority of pgB2FuIFN-α was not cleaved at the site between the amino-terminal (NH
2
) subunit and boIFN-α, whereas cleavage at the newly introduced site was normal. This resulted in virus particles that also contain the NH
2
-subunit/boIFN-α fusion protein within their envelopes. Our results demonstrate that BHV-1 gB can be used as a transporter for peptides and proteins which could be important for development of novel vaccines. In addition, the general principle might be useful for other applications, e.g., in gene therapy and also in nonviral systems.
Virion Proteins of Kaposi's Sarcoma-Associated Herpesvirus
Authors: Zhu Fan Xiu , Chong Jae Min , Wu Lijun , Yuan Yan
Published: December 2004

The proteins that compose a herpesvirus virion are thought to contain the functional information required for de novo infection, as well as virion assembly and egress. To investigate functional roles of Kaposi's sarcoma-associated herpesvirus (KSHV) virion proteins in viral productive replication and de novo infection, we attempted to identify virion proteins from purified KSHV by a proteomic approach. Extracellular KSHV virions were purified from phorbol-12-tetradecanoate-13-acetate-induced BCBL-1 cells through double-gradient ultracentrifugation, and their component proteins were resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Thirty prominent protein bands were excised and subjected to high-performance liquid chromatography ion trap mass spectrometric analysis. This study led to the identification of 24 virion-associated proteins. These include five capsid proteins, eight envelope glycoproteins, six tegument proteins, and five proteins whose locations in the virions have not yet been defined. Putative tegument proteins encoded by open reading frame 21 (ORF21), ORF33, and ORF45 were characterized and found to be resistant to protease digestion when purified virions were treated with trypsin, confirming that they are located within the virion particles. The ORF64-encoded large tegument protein was found to be associated with capsid but sensitive to protease treatment, suggesting its unique structure and array in KSHV virions. In addition, cellular β-actin and class II myosin heavy chain type A were found inside KSHV virions and associated with tegument-capsid structure. Identification of KSHV virion proteins makes it possible to study the functional roles of these virion proteins in KSHV replication and pathogenicity.
The
Red Clover Necrotic Mosaic Virus
RNA2
trans
-Activator Is Also a
cis
-Acting RNA2 Replication Element
Authors: Tatsuta Masahiro , Mizumoto Hiroyuki , Kaido Masanori , Mise Kazuyuki , Okuno Tetsuro
Published: December 2004

The expression of the coat protein gene requires RNA-mediated
trans
-activation of subgenomic RNA synthesis in
Red clover necrotic mosaic virus
(RCNMV), the genome of which consists of two positive-strand RNAs, RNA1 and RNA2. The
trans
-acting RNA element required for subgenomic RNA synthesis from RNA1 has been mapped previously to the protein-coding region of RNA2, whereas RNA2 is not required for the replication of RNA1. In this study, we investigated the roles of the protein-coding region in RNA2 replication by analyzing the replication competence of RNA2 mutants containing deletions or nucleotide substitutions. Our results indicate that the same stem-loop structure (SL2) that functions as a
trans
-activator for RNA-mediated coat protein expression is critically required for the replication of RNA2 itself. Interestingly, however, disruption of the RNA-RNA interaction by nucleotide substitutions in the region of RNA1 corresponding to the SL2 loop of RNA2 does not affect RNA2 replication, indicating that the RNA-RNA interaction is not required for RNA2 replication. Further mutational analysis showed that, in addition to the stem-loop structure itself, nucleotide sequences in the stem and in the loop of SL2 are important for the replication of RNA2. These findings suggest that the structure and nucleotide sequence of SL2 in RNA2 play multiple roles in the virus life cycle.
Incorporation of Three Endocytosed Varicella-Zoster Virus Glycoproteins, gE, gH, and gB, into the Virion Envelope
Authors: Maresova Lucie , Pasieka Tracy Jo , Homan Elizabeth , Gerday Erick , Grose Charles
Published: December 2004

The cytoplasmic tails of all three major varicella-zoster virus (VZV) glycoproteins, gE, gH, and gB, harbor functional tyrosine-based endocytosis motifs that mediate internalization. The aim of the present study was to examine whether endocytosis from the plasma membrane is a cellular route by which VZV glycoproteins are delivered to the final envelopment compartment. In this study, we demonstrated that internalization of the glycoproteins occurred in the first 24 h postinfection but was reduced later in infection. Using surface biotinylation of VZV-infected cells followed by a glutathione cleavage assay, we showed that endocytosis was independent of antibody binding to gE, gH, and gB. Subsequently, with this assay, we demonstrated that biotinylated gE, gH, and gB retrieved from the cell surface were incorporated into nascent virus particles isolated after density gradient sedimentation. To confirm and extend this finding, we repeated the above sedimentation step and specifically detected envelopes decorated with Streptavidin-conjugated gold beads on a majority of complete virions through examination by transmission electron microscopy. In addition, a gE-gI complex and a gE-gH complex were found on the virions. Therefore, the above studies established that VZV subsumed a postendocytosis trafficking pathway as one mechanism by which to deliver viral glycoproteins to the site of virion assembly in the cytoplasm. Furthermore, since a recombinant VZV genome lacking only endocytosis-competent gE cannot replicate, these results supported the conclusion that the endocytosis-envelopment pathway is an essential component of the VZV life cycle.
Understanding work related musculoskeletal pain: does repetitive work cause stress symptoms?
Authors: Bonde J P , Mikkelsen S , Andersen J H , Fallentin N , Bælum J , Svendsen S W , Thomsen J F , Frost P , Kærgaard A
Published: December 2004

Background:Pain in the neck and upper extremity is reported with high frequency in repetitive work. Mechanical overload of soft tissues seems a plausible mechanism, but psychological factors have received considerable attention during the past decade. If psychological factors are important for development of regional pain in repetitive work, stress symptoms would likely be on the causal path.

Aims:To examine whether objective measures of repetitive monotonous work are related to occurrence and development of stress symptoms.

Methods:In 1994–95, 2033 unskilled workers with continuous repetitive work and 813 workers with varied work were enrolled. Measures of repetitiveness and force requirements were quantified using video observations to obtain individual exposure estimates. Stress symptoms were recorded at baseline and after approximately one, two, and three years by the Setterlind Stress Profile Inventory.

Results:Repetitive work, task cycle time, and quantified measures of repetitive upper extremity movements including force requirements were not related to occurrence of stress symptoms at baseline or development of stress symptoms during three years of follow up.

Conclusions:The findings do not indicate that repetitive work is associated with stress symptoms, but small effects cannot be ruled out. Thus the results question the importance of mental stress mechanisms in the causation of regional pain related to repetitive work. However, the findings should be interpreted with caution because the stress inventory has not been validated against a gold standard.
Gender dependent accumulation of dioxins in smokers
Authors: Fierens S , Eppe G , De Pauw E , Bernard A
Published: December 2004

Aims:To evaluate the contribution of tobacco smoking to dioxin accumulation.

Methods:Dioxin (17 PCDD/F) concentrations in fasting blood from 251 subjects (161 never smokers, 54 past smokers, and 36 current smokers) were quantified.

Results:Whereas serum dioxin concentrations of male smokers were on average 40% higher than those of non-smokers, in women, smoking was associated with significantly lower serum dioxin levels. A synergistic potentiation of dioxin metabolism by tobacco smoke in women is postulated to explain these paradoxical findings.

Conclusions:Current smoking is associated with gender dependent effects on dioxin body burden and is a potential source of confounding in human studies using blood dioxins as indicators of exposure.
Work related physical activity and risk of a hospital discharge diagnosis of atrial fibrillation or flutter: the Danish Diet, Cancer, and Health Study
Authors: Frost L , Frost P , Vestergaard P
Published: December 2004

Background and Aims:Excessive sporting activities have been associated with risk of atrial fibrillation. To study if work related physical activity also confers risk of atrial fibrillation or flutter, the association between work related physical strain and the risk of a hospital discharge diagnosis (inpatient as well as outpatient) of atrial fibrillation or flutter was examined.

Methods:A population based prospective cohort study was conducted from December 1993 to December 2001 among 19 593 men and 18 807 women with a mean age at baseline of 56 years (range 50–65 years) in the Danish Diet, Cancer, and Health Study. The physical strain during working hours was categorised as sedentary, light, or heavy, and analysed using proportional hazard models. Subjects were followed up in the Danish National Registry of Patients and in the Danish Civil Registration System.

Results:During follow up (mean 5.7 years) a hospital discharge diagnosis of atrial fibrillation or flutter occurred in 305 men and 113 women. When using the risk of atrial fibrillation or flutter associated with sedentary work at a sitting position as a reference, no excess risk (unadjusted as well as adjusted) was found of atrial fibrillation or flutter associated with sedentary work in a standing position, light workload, or heavy workload in men or women.

Conclusion:No evidence was found of an association between physical activities during working hours and risk of a hospital discharge diagnosis of atrial fibrillation or flutter for men and women in the age group of 50–65 years.
Mortality in New Zealand workers exposed to phenoxy herbicides and dioxins
Authors: ’t Mannetje A , McLean D , Cheng S , Boffetta P , Colin D , Pearce N
Published: December 2004

Aims:To evaluate mortality in New Zealand phenoxy herbicide producers and sprayers exposed to dioxins.

Methods:Phenoxy herbicide producers (n = 1025) and sprayers (n = 703) were followed up from 1 January 1969 and 1 January 1973 respectively to 31 December 2000. A total of 813 producers and 699 sprayers were classified as exposed to dioxin and phenoxy herbicides. Standardised mortality ratios (SMR) were calculated using national mortality rates.

Results:At the end of follow up, 164 producers and 91 sprayers had died. Cancer mortality was reduced for sprayers (SMR = 0.82, 95% CI 0.57 to 1.14) and increased in exposed production workers (SMR = 1.24, 95% CI 0.90 to 1.67), especially for synthesis workers (SMR = 1.69), formulation and lab workers (SMR = 1.64), and maintenance/waste treatment/cleaning workers (SMR = 1.46). Lymphohaematopoietic cancer mortality was increased in exposed production workers (SMR = 1.65, 95% CI 0.53 to 3.85), especially for multiple myeloma (SMR = 5.51, 95% CI 1.14 to 16.1). Among sprayers, colon cancer (SMR = 1.94, 95% CI 0.84 to 3.83) showed increased mortality.

Conclusions:Results showed 24% non-significant excess cancer mortality in phenoxy herbicide producers, with a significant excess for multiple myeloma. Associations were stronger for those exposed to multiple agents including dioxin during production. Overall cancer mortality was not increased for producers and sprayers mainly handling final technical products, although they were likely to have been exposed to TCDD levels far higher than those currently in the general New Zealand population.
Biomonitoring of a worker population exposed to platinum dust in a catalyst production plant
Authors: Petrucci F , Violante N , Senofonte O , Cristaudo A , Di Gregorio M , Forte G , Alimonti A
Published: December 2004

Aims:To evaluate the occupational exposure to platinum in an industrial plant engaged in the production, recovery, and recycling of catalytic converters for the automotive traction and chemical industries.

Methods:Pt was determined in airborne particulate matter, and blood, urine, and hair of 106 exposed workers, 21 controls from the plant’s administrative offices, and 25 unexposed subjects.

Results:The highest air Pt level was found in the department of the plant in which supports are coated with acid metal solutions, where values of 2.39 and 4.83 μg/m3respectively were found in environmental airborne particulate matter and in air collected using personal sampler devices. The percentage of soluble Pt was also highest in this area, varying from 24% to 44% of the total. The biological data confirmed this trend, with mean concentrations in this site being higher than in other working areas: 1.86 μg/l (urine), 0.38 μg/l (blood), and 2.26 μg/kg (hair). The workers employed in the administrative sector, who were not directly exposed to Pt, had levels of contaminant lower than those of other workers, albeit 2–20 times higher than those of external controls. High correlations were obtained between Pt levels detected in airborne samples using personal devices and those found in urine and hair, but not in blood.

Conclusions:The background level of Pt in all areas of the factory implies widespread exposure for the workers. The most reliable biomarker was urine. Hair cannot be considered a good index of time related exposure, at least until more reliable methods of washing can be found that are able to remove exogenous Pt completely.
Factors influencing gene introgression into the allotetraploidCoffea arabicaL. from its diploid relatives
Authors: Herrera Juan C , Combes Marie C , Cortina Hernando , Lashermes Philippe
Published: December 2004

Factors controlling gene introgression into cultivated arabica coffee (Coffea arabica L.) were investigated. Interspecific triploid hybrid plants between the tetraploid species C. arabica (2n = 44) and a diploid species (2n = 22), either Coffea canephora or Coffea eugenioides, were backcrossed to C. arabica (male parent). Flow cytometric analysis of the nuclear DNA content revealed that most of the BC1individuals derived from triploid hybrids involving C. eugenioides were tetraploid or nearly tetraploid. Among the gametes produced by the interspecific triploid hybrids, those possessing approximately 22 chromosomes appeared strongly favored. The amount of introgression in BC1individuals (21 and 43 for the BC1progenies involving C. canephora and C. eugenioides, respectively) was estimated using species-specific microsatellite markers. A large number of introgressed markers was observed in all BC1individuals. Nevertheless, while the frequency of introgressed markers seemed as expected, assuming random chromosome segregation and diploid gamete formation, in the BC1derived from triploid hybrids involving C. canephora, this frequency appeared significantly lower in the BC1derived from triploid hybrids involving C. eugenioides. Furthermore, the comparison of reciprocal progenies between C. arabica and triploid interspecific hybrids (C. arabica × C. canephora) used as male or female parent revealed a very strong effect of the backcross direction.Key words: irregular meiosis, coffee, reciprocal crosses, molecular marker, triploid hybrids.
Development of SSR markers for the phylogenetic analysis of almond trees from China and the Mediterranean region
Authors: Xu Yong , Ma Rong-Cai , Xie Hua , Liu Jian-Ting , Cao Ming-Qing
Published: December 2004

Expressed sequence tag (EST) derived simple sequence repeats (SSRs, microsatellites) were screened and identified from 3863 almond and 10 185 peach EST sequences, and the spectra of SSRs in the non-redundant EST sequences were investigated after sequence assembly. One hundred seventy-eight (12.07%) almond SSRs and 497 (9.97%) peach SSRs were detected. The EST-SSR occurs every 4.97 kb in almond ESTs and 6.57 kb in peach, and SSRs with di- and trinucleotide repeat motifs are the most abundant in both almond and peach ESTs. Twenty one EST-SSRs were thereafter, developed and used together with 7 genomic SSRs, to study the genetic relationship among 36 almond (P. communis Fritsch.) cultivars from China and the Mediterranean area, as well as 8 accessions of other related species from the genus Prunus. Both EST-derived and genomic SSR markers showed high cross-species transferability in the genus. Out of the 112 polymorphic alleles detected in the 36 cultivated almonds, 28 are specific to Chinese cultivars and 25 to the others. The 44 accessions were clustered into 4 groups in the phylogenetic tree and the 36 almond cultivars formed two distinct subgroups, one containing only Chinese cultivars and one of unknown origin and the other only those originating from the Mediterranean area, indicating that Chinese almond cultivars have a distinct evolutionary history from the Mediterranean almond. Our preliminary results indicated that common almond was more closely related to peach (P. persica (L.) Batsch.) than to the four wild species of almond, (P. mongolica Maxim., P. ledebouriana Schleche, P. tangutica Batal., and P. triloba Lindl.). The implications of these SSR markers for evolutionary analysis and molecular mapping of Prunus species are discussed.Key words: expressed sequence tags (ESTs), microsatellites (SSRs), almond, P. communis Fritsch.
Creation of a BAC resource to study the structure and evolution of the banana (Musa balbisiana) genome
Authors: Šafář Jan , Noa-Carrazana Juan Carlos , Vrána Jan , Bartoš Jan , Alkhimova Olena , Sabau Xavier , Šimková Hana , Lheureux Fabrice , Caruana Marie-Line , Doležel Jaroslav , Piffanelli Pietro
Published: December 2004

The first bacterial artificial chromosome (BAC) library of the banana species Musa balbisiana 'Pisang Klutuk Wulung' (PKW BAC library) was constructed and characterized. One improved and one novel protocol for nuclei isolation were employed to overcome problems caused by high levels of polyphenols and polysaccharides present in leaf tissues. The use of flow cytometry to purify cell nuclei eliminated contamination with secondary metabolites and plastid DNA. Furthermore, the usefulness of the inducible pCC1BAC vector to obtain a higher amount of BAC DNA was demonstrated. The PKW BAC library represents nine haploid genome equivalents of M. balbisiana and its mean insert size is 135 kb. It consists of two sublibraries, of which the first one (SN sublibrary with 24 960 clones) was prepared according to an improved standard nuclei isolation protocol, whereas the second (FN sublibrary with 11 904 clones) was obtained from flow-sorted nuclei. Screening with 12 RFLP probes, which were genetically anchored to 8 genetic linkage groups of the banana species Musa acuminata, revealed an average of 11 BAC clones per probe, thus confirming the genome coverage estimated based on the insert size, as well as a high level of conservation between the two species of Musa. Localization of selected BAC clones to mitotic chromosomes using FISH indicated that the BAC library represented a useful resource for cytogenetic mapping. As the first step in map-based cloning of a genetic factor that is involved in the activation of integrated pararetroviral sequences of Banana streak virus (BSV), the BSV expressed locus (BEL) was physically delimited. The PKW BAC library represents a publicly available tool, and is currently used to reveal the integration and activation mechanisms of BSV sequences and to study banana genome structure and evolution.Key words: bacterial artificial chromosome library, banana, BAC-FISH, flow cytometry, Musa balbisiana, Banana streak virus, BSV.
High level of genetic diversity among spelt germplasm revealed by microsatellite markers
Authors: Bertin P , Grégoire D , Massart S , de Froidmont D
Published: December 2004

The genetic diversity of spelt (Triticum aestivum (L.) Thell. subsp. spelta (L.) Thell.) cultivated presently is very narrow. Although the germplasm collections of spelt are extensive, the related genetic knowledge is often lacking and makes their use for genetic improvement difficult. The genetic diversity and structure of the spelt gene pool held in gene banks was determined using 19 simple sequence repeat (SSR) markers applied to 170 spelt accessions collected from 27 countries and 4 continents. The genetic distances (1 – proportion of shared alleles) were calculated and an unweighted pair-group method with arithmetic averaging (UPGMA)-based dendrogram was generated. The genetic diversity was high: 259 alleles were found and the mean interaccession genetic distance was 0.782 ± 0.141. The dendrogram demonstrated the much higher genetic diversity of spelt held in germplasm collections than in the currently used genotypes. Accessions with the same geographical origin often tended to cluster together. Those from the Middle East were isolated first. All but one of the Spanish accessions were found in a unique subcluster. Most accessions from eastern Europe clustered together, while those from northwestern Europe were divided into two subclusters. The accessions from Africa and North America were not separated from the European ones. This analysis demonstrates the extent of genetic diversity of spelts held in germplasm collections and should help to widen the genetic basis of cultivated spelt in future breeding programs.Key words: spelt, SSR, microsatellites, genetic diversity, germplasm.
Transmission of maize chromosome 9 rearrangements in oat–maize radiation hybrids
Authors: Vales M Isabel , Riera-Lizarazu Oscar , Rines Howard W , Phillips Ronald L
Published: December 2004

Oat–maize radiation hybrids are oat (Avena sativa L.) plants carrying radiation-induced subchromosome fragments of a given maize (Zea mays L.) chromosome. Since first-generation radiation hybrids contain various maize chromosome rearrangements in a hemizygous condition, variation might be expected in the transmission of these rearrangements to subsequent generations. The transmission and integrity of maize chromosome 9 rearrangements were evaluated in progenies of 30 oat–maize radiation hybrids by using a series of DNA-based markers and by genomic in situ hybridization. Maize chromosome 9 rearrangements were reisolated by self-fertilization in 24 of the 30 radiation hybrid lineages. Normal and deleted versions of maize chromosome 9 were transmitted at similar frequencies of 9.1% and 7.6%, respectively, while intergenomic translocations were transmitted at a significantly higher frequency of 47.6%. Most lines (93%) that inherited a rearrangement had it in the hemizygous condition. Lines with a rearrangement in the homozygous state (7%) were only identified in lineages with intergenomic translocations. Homozygous lines are more desirable from the perspective of stock maintenance, since they may stably transmit a given rearrangement to a subsequent generation. However, their isolation is not strictly required, since hemizygous lines can also be used for genome mapping studies.Key words: Avena sativa, Zea mays, addition lines, chromosome rearrangements.
Molecular characterization of a gene encodingN-myristoyl transferase (NMT) fromTriticum aestivum(bread wheat)
Authors: Dumonceaux Tim , Rajala Raju V.S , Sharma Rajendra , Selvaraj Gopalan , Datla Raju
Published: December 2004

Myristoyl-CoA:protein N-myristoyl transferase (NMT; EC 2.3.1.97) acylates the Gly residue abutting the N-terminal Met with a myristic acid following the removal of the Met residue in certain eukaryotic proteins, and in some cases myristoylation is essential to cell growth and survival. We report the cloning of a full-length cDNA encoding NMT from Triticum aestivum (TaNMT). The cDNA included a predicted open reading frame of 1317 nucleotides, which encoded a predicted protein of 438 amino acids containing all of the residues that are important for NMT activity. The TaNMT amino acid and nucleotide sequences were compared with NMTs from 14 other species encompassing a wide array of taxonomic groups. Among the experimentally validated NMTs, TaNMT was most similar to that of Arabidopsis thaliana. Southern blot analysis of wheat genomic DNA showed that TaNMT is encoded by a single copy gene, with one copy per haploid genome. We expressed TaNMT in Escherichia coli cells and determined that the recombinant protein possessed NMT activity, catalyzing the N-myristoylation of peptides from known or putatively myristoylated proteins from plants and animals without a strong preference for the plant peptides. TaNMT is the second experimentally validated plant NMT sequence and the first from a monocotyledonous species.Key words: N-myristoyl transferase, myristoylation, protein modification, wheat, plant development.
Increased spontaneous DNA damage in Cu/Zn superoxide dismutase (SOD1) deficientDrosophila
Authors: Woodruff R C , Phillips J P , Hilliker A J
Published: December 2004

The superoxide dismutases (SODs) protect oxygen-using cells against reactive oxygen species, the potentially toxic by-products of respiration, oxidative metabolism, and radiation. We have previously shown that genetic disruption of CuZn SOD (SOD1) in Drosophila imparts a recessive phenotype of reduced lifespan, infertility, and hypersensitivity to oxidative stress. We now show that the absence of SOD1 increases spontaneous genomic damage. The increase in spontaneous mutation rate occurs in SOD1-null mutants in somatic cells as well as in the germ line. Further, we show that specific DNA repair-defective mutations, which are easily tolerated in SOD1+flies, lead to high mortality when introduced into the SOD1-null homozygous mutant background.Key words: Drosophila melanogaster, superoxide dismutase, mutations, germ and somatic cells, lethal and somatic mutations, reactive oxygen.
A COMPARATIVE STUDY OF PERFORMANCE OF THE DESIGN STRATEGIC GROUPS AND DESIGN STRATEGIES
Authors: CHANG WEN-CHIH , HSU YEN
Published: December 2004

The results generated from a questionnaire survey conducted in the period of 2002 to 2003 have shown that Taiwanese home appliance firms' product design strategy can be classified into passive response, aggressive response, and R&D focus groups according to characteristics classified by factor analysis and cluster analysis. Differences in issues related to the design strategy adopted by each group are highlighted from case studies. Performance in new product development differs among strategic groups. Overall, the aggressive response group performs the best, followed by the R&D focus group, and finally the passive response group. Some relationships between the design strategy related issues adopted by each strategic group and performance have been found after comparisons between them.
THE RELATIONSHIP OF PERCEIVED ORGANIZATIONAL INNOVATIVENESS (PORGI) ON IS&T EMPLOYEE CONTINUANCE: A LISREL MODEL
Authors: SOCKEL HY , MAK BRENDA
Published: December 2004

This paper explores how employees' perception of an organization's innovativeness impacts their desire to continue an association with the organization. The study uses Structural Equation Modeling — LISREL to explore the relationship between latent constructs of the employees' Perceived Job Satisfaction, and Perceived Organizational Innovativeness (PORGI) with their desire for (employment) Continuance with the organization. PORGI is measured through perceived innovation management, organizational career culture, personnel and innovation management policies. The latent construct of "Employee Continuance" is measured through loyalty and a desire to stay. The latent construct of Job Satisfaction is measured by the perceived job satisfaction of the employees.

A survey was conducted among Information Systems and Technology (IS&T) employees and the data was analyzed using LISREL confirmatory factor analysis. The results indicate that Perceived Organizational Innovativeness and Job Satisfaction have significant impact on employee retention. Employees that perceived the organization as being innovative demonstrated higher levels of loyalty and had a higher desire to stay connected with their organization. The study concludes that it behooves organizations to support innovative technologies, if only to improve employee retention. Additional organizational implications and technological adoption strategies to strengthen employee retention are discussed.
Dehydroepiandrosterone inhibits the amplification of glucocorticoid action in adipose tissue
Authors: Apostolova Galina , Schweizer Roberto A. S. , Balazs Zoltan , Kostadinova Radina M. , Odermatt Alex
Published: December 2004

Dehydroepiandrosterone (DHEA) exerts beneficial effects on blood glucose levels and insulin sensitivity in obese rodents and humans, resembling the effects of peroxisome proliferator-activated receptor-γ (PPARγ) ligands and opposing those of glucocorticoids; however, the underlying mechanisms remain unclear. Glucocorticoids are reactivated locally by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), which is currently considered as a promising target for the treatment of obesity and diabetes. Using differentiated 3T3-L1 adipocytes, we show that DHEA causes downregulation of 11β-HSD1 and dose-dependent reduction of its oxoreductase activity. The effects of DHEA were comparable with those of the PPARγ agonist rosiglitazone but not additive. Furthermore, DHEA reduced the expression of hexose-6-phosphate dehydrogenase, which stimulates the oxoreductase activity of 11β-HSD1. These findings were confirmed in white adipose tissue and in liver from DHEA-treated C57BL/6J mice. Analysis of the transcription factors involved in the DHEA-dependent regulation of 11β-HSD1 expression revealed a switch in CCAAT/enhancer-binding protein (C/EBP) expression. C/EBPα, a potent activator of 11β-HSD1 gene transcription, was downregulated in 3T3-L1 adipocytes and in liver and adipose tissue of DHEA-treated mice, whereas C/EBPβ and C/EBPδ, attenuating the effect of C/EBPα, were unchanged or elevated. Our results further suggest a protective effect of DHEA on adipose tissue by upregulating PPARα and downregulating leptin, thereby contributing to the reduced expression of 11β-HSD1. In summary, we provide evidence that some of the anti-diabetic effects of DHEA may be caused through inhibition of the local amplification of glucocorticoids by 11β-HSD1 in adipose tissue.
Absence of p21
Waf1/Cip1/Sdi1
Modulates Macrophage Differentiation and Inflammatory Response and Protects Against Atherosclerosis
Authors: Merched Aksam J. , Chan Lawrence
Published: December 2004

Background—

The tumor suppressor p53 protects against atherosclerosis progression in several different mouse models. A major target of p53 is p21, the cyclin-dependent kinase inhibitor that regulates entry into the cell cycle of different types of cells, including stem cells. p21 is also involved in the maturation and differentiation of monocytes into macrophages.

Methods and Results—

We studied the effect of p21
Waf1
inactivation on atherosclerosis development in apolipoprotein E-deficient mice (
apoE

−
/
−

). Contrary to previous data suggesting a protective role for p21, we found that absence of p21, either globally or in bone marrow-derived cells, protects against atherosclerosis. Atherosclerotic lesions of
p21

−
/
−

/apoE

−
/
−

mice exhibit a more stable phenotype, with increased apoptosis and reduced inflammatory vascular cell adhesion molecule-1 immunostaining but no difference in cellular proliferation compared with lesions of
p21

+/+

/apoE

−
/
−

mice. Because bone marrow-derived cells mediate many of the effects of p21, we examined the expression profile of 23 genes in macrophages using real-time polymerase chain reaction. Compared with their
p21

+/+

counterparts, peritoneal macrophages of
p21

−
/
−

mice express lower levels of proinflammatory markers, including macrophage inflammatory proteins 1 and 2 and interleukin-1α, and higher levels of putative protective genes, such as scavenger receptor type B-I and LDL receptor-related protein. Furthermore, we found that, in comparison with
p21

+/+

macrophages,
p21

−
/
−

macrophages displayed increased phagocytic activity toward fluorescent latex microspheres as well as apoptotic cells, thus uncovering a novel mechanism of the antiinflammatory activity of
p21

−
/
−

macrophages.

Conclusions—

Loss of p21 protects against atherosclerosis in
apoE

−
/
−

mice. The data underscore the important role of p21 in macrophage function and inflammation and provide insight into the mechanism of the proatherogenic effect of p21.
CDC/AHA Workshop on Markers of Inflammation and Cardiovascular Disease
Authors: Fortmann Stephen P. , Ford Earl , Criqui Michael H. , Folsom Aaron R. , Harris Tamara B. , Hong Yuling , Pearson Thomas A. , Siscovick David , Vinicor Frank , Wilson Peter F.
Published: December 2004

This article summarizes epidemiological studies of inflammation markers, particularly C-reactive protein, and cardiovascular disease as of early 2002. Gaps in the research and the public health practice implications are also discussed. Although considerable work has been published since this review was completed, the perspectives and issues presented are still useful in evaluating the use of inflammation markers for risk stratisfication and prevention.