bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of the REE in Geological Reference Materials DTS‐1 (Dunite) and PCC‐1 (Peridotite) by Ultrasonic and Microconcentric Desolvating Nebulisation ICP‐MS
Authors: Jain Jinesh C. , Field M. Paul , Neal Clive R. , Ely James C. , Sherrell Robert M.
Published: May 2007

Inductively coupled plasma‐mass spectrometry is well suited for the precise, accurate and rapid determination of rare earth elements in most geological samples. However, determination of rare earth elements in certain mantle‐derived materials, without applying preconcentration techniques, remains problematical due to low natural concentrations (generally < 1 ng g−1). Consequently, USGS reference materials DTS‐1 (a dunite) and PCC‐1 (a partially serpentinized harzburgite) have only suggested rather than recommended values for the rare earth elements in reference material compilations. We compared results obtained using two ICP‐MS instruments: a U‐5000AT ultrasonic nebuliser coupled to a PQ2+ quadrupole ICP‐MS and an ELEMENT sector field ICP‐MS equipped with a MCN‐6000 microconcentric desolvating nebuliser, with the suggested literature values for these two reference materials. Precision and accuracy of analytical methods employed by both instruments were demonstrated by excellent relative standard deviations (< 2%) and inter‐laboratory agreement (< 5%) for numerous analyses of BHVO‐1 and BIR‐1, which are well established with rare earth elements contents at the μg g−1 level. Repeat analyses of DTS‐1 and PCC‐1 at each laboratory indicate that each method is generally precise to better than 5% at sub‐g g−1 levels. Furthermore, values from both instruments generally agree to within 10%. Our DTS‐1 and PCC‐1 values agree reasonably well with selected data reported in the literature (except for Ce and Sm in DTS‐1) but exhibit poorer agreement with reported compilation values. With the demonstrated level of precision and accuracy, we contend that these new values for DTS‐1 and PCC‐1, generated by two different instruments, are the best estimates of the true whole‐rock composition of these samples reported to date.
Stevns Klint Fish Clay (FC‐1): Preparation of, and Preliminary Results for, a Candidate Reference Material
Authors: Gwozdz Rajmund , Hansen Hans J. , Rasmussen Kaare L.
Published: May 2007

The collapse of a section of the cliff at Stevns Klint, Denmark in 1986 provided a unique opportunity to collect about 50 kg of Fish Clay representing the Cretaceous‐Tertiary (K‐T) boundary layer. In this paper, details of the preparation of this sample are presented, together with preliminary analytical results to support the development of this sample as a reference material, particularly for the determination of iridium and the other platinum‐group elements in clays and sediments associated with K‐T boundary studies and in other environmental samples collected to study the effects of automobile exhaust catalysts.
A Revised Analytical Method for HCO3‐ and CO32‐Determinations in Geothermal Waters: An Assessment of IAGC and IAEA Interlaboratory Comparisons
Authors: Verma Mahendra P.
Published: May 2007

A statistical evaluation of the results of HCO3‐ determinations in geothermal waters during the interlaboratory comparison programmes of the International Association of Geochemistry and Cosmochemistry (IAGC) and International Atomic Energy Agency (IAEA) indicated that the analytical uncertainty increases with decreasing concentration of HCO3‐ and was ˜ 25% for 50 μg ml‐1 and ˜ 60% for 25 μg ml‐1 of HCO3‐. The analytical method (Method 1) used by chemists and hydrologists works well for waters containing carbonic alkalinity, whereas Method 2 used by geochemists is conceptually incorrect. A stepwise comparison between the theoretical and experimental titration results for a given concentration Na2CO3 (0.0988 mol l‐1) solution was performed to understand the limitations of the titration method for geothermal water analysis. Backward titration from the carbonic acid equivalence point (H2CO3EP) to the original pH after CO2 removal, as had been practised earlier in the geothermal industry, in order to estimate the contribution of silicic and boric alkalinities to the total alkalinity, is incorrect because the amount of standard base (NaOH) added is equivalent to silicic and boric alkalinities plus some OH‐ alkalinity. In a Na2CO3 solution, the added NaOH is equivalent to OH‐ alkalinity only. Backward titration is only needed from the forward titration end point to the H2CO3EP in order to correct the total alkalinity for the excess of standard acid (HCl) added during the forward titration. In the case of a Na2CO3 solution, the H2CO3EP, after removal of CO2 during the forward titration, is at pH = 7, not at pH = 4.5 (3.8) as has been considered in literature. Similarly, the liberation of CO2 during titration occurs well before the point expected theoretically and it is less for shorter titration time. The revised procedure for the determination of carbonic species concentration is presented and illustrated for a water sample from Alchichica Lake, Puebla, Mexico.
Boron Isotopic Composition and Concentration of Ten Geological Reference Materials
Authors: Rosner Martin , Meixner Anette
Published: May 2007

We present boron isotope and concentration data from magmatic (komatiitic to rhyolitic) and sedimentary geological silicate and artificial glass reference materials that cover a wide spectrum of boron isotope compositions and boron concentrations. Boron isotope compositions were determined by TIMS (Cs2BO2+ ‐graphite and BO2‐ method) and boron concentrations by ICP‐AES. Boron concentrations ranged from 7 to 159μ g‐1 and agree within 14% with published values. Based on replicate analyses of individually prepared sample aliquots an overall external reproducibility of better than 10% was determined. The obtained δ11B values ranged from ‐12.6 to +13.6% and were reproducible within 1.1 % (2 RSD; excluding NTIMS) on the basis of individually prepared sample aliquots. The δ11B values of JA‐1 (+5.3%), JB‐3 (+5.9%) and JR‐2 (+2.9%) overlap the published data within analytical uncertainty. For the first time δ11B values for the TB (‐12.6%) and the MPI‐DING glasses GOR‐128‐G (+13.6%), GOR‐132‐G (+7.1 %) and StHs6/80‐G (‐4.5%) are reported. The δ11B values obtained by the Cs2BO2+ ‐graphite and the BO2‐ method as well as the majority of δ11B values obtained using different sample preparation methods agree within analytical uncertainty. Therefore, we conclude that none of these analytical methods introduce any systematic error on the obtained δ11B values.
Does l‐carnitine have any effect on cold preservation injury of non‐fatty liver in the University of Wisconsin solution?
Authors: Coskun Abdurrahman , Gunal Omer , Sahin Ibrahim , Aslaner Arif , Yildirim Umran , Yavuz Ozlem
Published: May 2007

Aim:  To evaluate the protective effect of l‐carnitine on liver tissue preserved in University of Wisconsin (UW) solution.

Methods:  Twenty Wistar Albino rats were divided into two groups, a control (UW) group and a UW plus l‐carnitine group. Retrieved liver grafts were preserved in UW and UW plus l‐carnitine solutions at +4°C. Preservation solution samples were assessed at 2, 24, 36, and 48 h to measure alanine aminotransferase and acid phosphatase activity. Tissue injury was scored on paraffin sections.

Results:  No micro or macrovacuolar fat droplets were observed in the tissue slices. l‐Carnitine effectively decreased enzyme release when added to UW solution (P < 0.05).

Conclusion:  In addition to fatty liver, l‐carnitine might be a metabolic adjunct in preservation solutions for non‐fatty liver within UW solution.
Evaluation of the effects of combination therapy with branched‐chain amino acid and zinc supplements on nitrogen metabolism in liver cirrhosis
Authors: Hayashi Miho , Ikezawa Kenji , Ono Akiko , Okabayashi Sachiyo , Hayashi Yoshito , Shimizu Satoshi , Mizuno Tatsuyoshi , Maeda Kosaku , Akasaka Tomofumi , Naito Masafumi , Michida Tomoki , Ueshima Dan , Nada Takayuki , Kawaguchi Kiyotaka , Nakamura Tekefumi , Katayama Kazuhiro
Published: May 2007

Aim:  Disorders of protein metabolism in liver cirrhosis can affect prognosis or cause complications. Treatment with branched‐chain amino acid (BCAA) and zinc supplements has been shown to be effective against abnormal nitrogen metabolism in liver cirrhosis. There are, however, few studies on the effects of combining these supplements. In this study, the effect of combining BCAA and zinc treatment in cirrhosis was investigated.

Methods:  Forty patients with liver cirrhosis who had blood albumin levels of 3.5 g/dL or less and blood zinc levels of 70 μg/dL or less were randomized to receive either BCAA alone or a combination of BCAA and zinc supplements. Blood albumin, the Fischer ratio, and ammonia levels were compared over 5–6 months of treatment.

Results:  In the combination group, the post/pre treatment change ratio in blood ammonia levels decreased significantly (0.87 ± 0.26 vs. 1.22 ± 0.38, P = 0.0033), and the change ratio in the Fischer ratio increased significantly (1.22 ± 0.29 vs. 1.08 ± 0.16, P = 0.0165) in comparison with the BCAA monotherapy group. The change ratio in blood albumin levels showed no significant difference between the groups (1.01 ± 0.07 vs. 1.03 ± 0.08, P = 0.4646).

Conclusions:  More improvement in disorders of nitrogen metabolism in liver cirrhosis occurred after administration of BCAA with zinc than after BCAA alone over 5–6 months of treatment. Further investigation is necessary to determine mechanisms of the action and longer‐term clinical efficacy.
Genetic background of Japanese patients with adult‐onset storage diseases in the liver
Authors: Hayashi Hisao , Wakusawa Shinya , Yano Motoyoshi , Okada Toshihide
Published: May 2007

In contrast to primary lysosomal diseases in young subjects, adult‐onset liver storage disorders may be explained by non‐lysosomal genetic defects. The aim of the present review is to summarize the genetic backgrounds of Japanese patients with hemochromatosis of unknown etiology, Wilson disease of primary copper toxicosis, and the black liver of Dubin–Johnson syndrome. Three patients with middle‐age onset hemochromatosis were homozygous for mutations of HJV and two patients were homozygous for mutations of TFR2. Minor genes other than HJV and TFR2 might be involved in Japanese patients. Five of the six patients with Wilson disease were compound heterozygous, while the remaining patient was heterozygous for the mutation in ATP7B responsible for copper toxicosis. Involvement of MURR1 was not proved in the heterozygote of ATP7B. Because of ferroxidase deficiency,most patients had secondary lysosomes shared by cuprothioneins and iron complex. Six patients with Dubin–Johnson syndrome were homozygous or compound heterozygous for mutant MRP2. Despite complex metabolic disorders, the syndrome had a single genetic background. Thus, most patients with adult‐onset lysosomal proliferation in the liver had genetic defects in non‐lysosomal organelles, named the secondary lysosomal diseases. The proliferating lysosomes in these conditions seemed to be heterogeneous in their matrices.
Modeling and Control Considerations for Powered Lower-Limb Orthoses: A Design Study for Assisted STS
Authors: Eby Wesley R. , Kubica Eric
Published: May 2007

Lower-limb orthotic devices may be used to aid or restore mobility to the impaired user. Powered orthoses, in particular, hold great potential in improving the quality of life for individuals with locomotor difficulties because active control of an orthosis can aid limb movement in common tasks that may even be impossible if unaided. However, these devices have primarily remained the products of research labs with the number of effective commercial applications for the laity being nearly nonexistent. This paper provides an overview of the current status of powered orthoses and goes on to discuss key issues in modeling and control of powered orthoses so that designers can have a unified framework in developing user-oriented devices. Key concepts are demonstrated for a powered knee-orthosis intended for assisting the sit-to-stand task, and both pneumatic muscle and dc motor actuators are considered in this conceptual design study. In the final analysis, we conclude that the ability to provide sit-to-stand assistance is profoundly dependent on the type of control signal employed to control the actuator from the user–orthosis interface.
Enhanced Ex Vivo Stimulation ofMycobacterium tuberculosis-Specific T Cells in Human Immunodeficiency Virus-Infected Persons via Antigen Delivery by theBordetella pertussisAdenylate Cyclase Vector
Authors: Connell Tom G. , Shey Muki S. , Seldon Ronnett , Rangaka Molebogeng X. , van Cutsem Gilles , Simsova Marcela , Marcekova Zuzana , Sebo Peter , Curtis Nigel , Diwakar Lavanya , Meintjes Graeme A. , Leclerc Claude , Wilkinson Robert J. , Wilkinson Katalin A.
Published: May 2007

The genetically detoxifiedBordetella pertussisadenylate cyclase is a promising delivery system for immunodominant tuberculosis antigens in gamma interferon release assays. This system has not been evaluated in human immunodeficiency virus (HIV)-infected persons in high tuberculosis prevalence areas. A whole-blood gamma interferon release assay withMycobacterium tuberculosisantigens (early-secreted antigenic target 6, culture filtrate protein 10, alpha-crystallin 2, and TB10.3) delivered by adenylate cyclase in addition to native tuberculosis antigens (without adenylate cyclase delivery) was evaluated in 119 adults in Khayelitsha Township, Cape Town, South Africa. Results were compared to tuberculin skin test results of 41 HIV-positive and 42 HIV-negative asymptomatic persons, in addition to 36 HIV-positive persons with recently diagnosed smear- or culture-positive pulmonary tuberculosis. Delivery of tuberculosis antigens by adenylate cyclase decreased by 10-fold the amount of antigen required to restimulate T cells. Furthermore, the responses of HIV-positive persons with a low response to native tuberculosis antigens were enhanced when these antigens were delivered by adenylate cyclase. When gamma interferon responses to the tuberculosis antigens (with or without delivery by adenylate cyclase) were combined, a significantly higher number of patients were scored positive than by tuberculin skin testing. Ex vivo responses to tuberculosis antigens delivered by adenylate cyclase are maintained in the context of HIV infection. Our findings suggest that the majority of those in this population are infected with tuberculosis, which is of significant public health importance.
Evaluation of Serological Tests To Identify
Trypanosoma cruzi
Infection in Humans and Determine Cross-Reactivity with
Trypanosoma rangeli
and
Leishmania
spp
Authors: Caballero Zuleima C. , Sousa Octavio E. , Marques Waldelania P. , Saez-Alquezar Amadeo , Umezawa Eufrosina S.
Published: May 2007

Five commercially available enzyme-linked immunosorbent assays (ELISAs), one in-house ELISA, and two hemagglutination assays were evaluated to determine their diagnostic accuracy for Chagas' disease in two studies. In study 1, ELISA kits showed 100% sensitivity, but specificities ranged from 82.84% to 100% when leishmaniasis cases were included and from 95.57% to 100% when leishmaniasis cases were excluded. Kits using recombinant antigens or synthetic peptides are more specific than those using crude extracts from
Trypanosoma cruzi
epimastigote forms. Kits evaluated in Panama, in study 2, showed 75% to 100% sensitivity and 97.12% to 100% specificity. These data were obtained by using a Western blot assay with
T. cruzi
trypomastigote excreted-secreted antigens as a reference test to confirm
T. cruzi
infection.
Dengue Virus Detection Using Whole Blood for Reverse Transcriptase PCR and Virus Isolation
Authors: Klungthong Chonticha , Gibbons Robert V. , Thaisomboonsuk Butsaya , Nisalak Ananda , Kalayanarooj Siripen , Thirawuth Vipa , Nutkumhang Naowayubol , Mammen Mammen P. , Jarman Richard G.
Published: May 2007

Dengue is one of the most important diseases in the tropical and subtropical regions of the world, with an estimated 2.5 billion people being at risk. Detection of dengue virus infections has great importance for the clinical management of patients, surveillance, and clinical trial assessments. Traditionally, blood samples are collected in serum separator tubes, processed for serum, and then taken to the laboratory for analysis. The use of whole blood has the potential advantages of requiring less blood, providing quicker results, and perhaps providing better sensitivity during the acute phase of the disease. We compared the results obtained by reverse transcriptase PCR (RT-PCR) with blood drawn into tubes containing EDTA and those obtained by RT-PCR with blood samples in serum separator tubes from 108 individuals clinically suspected of being infected with dengue virus. We determined that the extraction of RNA from whole blood followed by RT-PCR resulted in a higher detection rate than the use of serum or plasma. Using a selection of these samples, we also found that our ability to detect virus by direct C6/36 cell culture and mosquito inoculation was enhanced by using whole blood but not to the same extent as that seen by the use of RT-PCR.
RTX Toxin Actin Cross-Linking Activity in Clinical and Environmental Isolates of
Vibrio cholerae
Authors: Cordero Christina L. , Sozhamannan Shanmuga , Satchell Karla J. Fullner
Published: May 2007

Vibrio cholerae
strains from diverse O-antigen groups were evaluated for RTX toxin actin cross-linking activity. This study demonstrates that the actin cross-linking domain sequence is present within
rtxA
in the majority of clinical and environmental isolates tested, and the RTX toxin produced by these strains catalyzes the covalent cross-linking of cellular actin.
Comparison of Two Versions of the IDI-MRSA Assay Using Charcoal Swabs for Prospective Nasal and Nonnasal Surveillance Samples
Authors: Zhang Sean X. , Drews Steven J. , Tomassi Joanne , Katz Kevin C.
Published: May 2007

An updated IDI-MRSA assay version was released to address the assay's low positive predictive value (PPV). A prospective analysis of two assay versions indicated no significant improvement in the PPV. Colonization by methicillin-resistant
Staphylococcus aureus
in 24% of patients would not have been detected if only nasal samples had been tested, as approved, by this molecular method.
Cystitis Caused by
Aeromonas caviae
Authors: Al-Benwan Khalifa , Abbott Sharon , Janda J. Michael , Huys Geert , Albert M. John
Published: May 2007

Aeromonas
sp. organisms rarely cause urinary tract infection. We report for the first time a case of urinary tract infection caused by
A. caviae
in an adult patient with a history of increased frequency of urination, dysuria, hematuria, and weight loss.
Clinical Validation of the Molecular BD GeneOhm StaphSR Assay for Direct Detection of
Staphylococcus aureus
and Methicillin-Resistant
Staphylococcus aureus
in Positive Blood Cultures
Authors: Stamper Paul D. , Cai Mian , Howard Tracy , Speser Sharon , Carroll Karen C.
Published: May 2007

The rapid detection of
Staphylococcus aureus
bacteremia and a swift determination of methicillin susceptibility has serious clinical implications affecting patient mortality. This study evaluated the StaphSR assay (BD GeneOhm, San Diego, CA), a real-time PCR assay, for the identification and differentiation of methicillin-susceptible
S. aureus
(MSSA) and methicillin-resistant
S. aureus
(MRSA) from 300 positive blood cultures. The BD GeneOhm StaphSR assay was performed and interpreted according to the manufacturer's recommendations. Positive blood cultures (containing predominantly gram-positive cocci in clusters) were subcultured on 5% sheep blood agar plates. After 18 to 24 h of incubation, isolates morphologically consistent with
S. aureus
were presumptively identified by latex agglutination (Staphaurex Plus; Remel, Lenexa, KS). Susceptibility testing was initially performed with the Phoenix automated microbiology system (BD Diagnostics, Sparks, MD). Additional susceptibility testing of samples with discrepant results was done using BBL oxacillin screen agar (BD Diagnostics, Sparks, MD), oxacillin and cefoxitin Etests (AB Biodisk, Solna, Sweden) on Mueller-Hinton agar, an immunoassay for penicillin binding protein 2′ (Denka Seiken Co., Tokyo, Japan), and
mecA
PCR. The sensitivity, specificity, and positive and negative predictive values of the BD GeneOhm StaphSR assay for MSSA detection were 98.9, 96.7, 93.6, and 99.5%, respectively. For the detection of MRSA, the BD GeneOhm StaphSR assay was 100% sensitive and 98.4% specific; positive and negative predictive values for MRSA detection were 92.6 and 100%, respectively. Inhibition was seen with only one sample, and the issue was resolved upon retesting. The BD GeneOhm StaphSR assay appears to be a valuable diagnostic tool for quickly differentiating bacteremia caused by MSSA and MRSA from that caused by other gram-positive cocci.
Phylogenetic Analysis and Structural Predictions of Human Adenovirus Penton Proteins as a Basis for Tissue-Specific Adenovirus Vector Design
Authors: Madisch Ijad , Hofmayer Soeren , Moritz Christian , Grintzalis Alexander , Hainmueller Jens , Pring-Akerblom Patricia , Heim Albert
Published: May 2007

The penton base is a major capsid protein of human adenoviruses (HAdV) which forms the vertices of the capsid and interacts with hexon and fiber protein. Two hypervariable loops of the penton are exposed on the capsid surface. Sequences of these and 300 adjacent amino acid residues of all 51 HAdV and closely related simian adenoviruses were studied. Adjacent sequences and predicted overall secondary structure were conserved. Phylogenetic analysis revealed clustering corresponding to the HAdV species and recombination events in the origin of HAdV prototypes. All HAdV except serotypes 40 and 41 of species F exhibited an integrin binding RGD motif in the second loop. The lengths of the loops (HVR1 and RGD loops) varied significantly between HAdV species with the longest RGD loop observed in species C and the longest HVR1 in species B. Long loops may permit the insertion of motifs that modify tissue tropism. Genetic analysis of HAdV prime strain p17′H30, a neutralization variant of HAdV-D17, indicated the significance of nonhexon neutralization epitopes for HAdV immune escape. Fourteen highly conserved motifs of the penton base were analyzed by site-directed mutagenesis of HAdV-D8 and tested for sustained induction of early cytopathic effects. Thus, three new motifs essential for penton base function were identified additionally to the RGD site, which interacts with a secondary cellular receptor responsible for internalization. Therefore, our penton primary structure data and secondary structure modeling in combination with the recently published fiber knob sequences may permit the rational design of tissue-specific adenoviral vectors.
A Recombinant Human Monoclonal Antibody to Human Metapneumovirus Fusion Protein That Neutralizes Virus In Vitro and Is Effective Therapeutically In Vivo
Authors: Williams John V. , Chen Zhifeng , Cseke Gabriella , Wright David W. , Keefer Christopher J. , Tollefson Sharon J. , Hessell Ann , Podsiad Amy , Shepherd Bryan E. , Sanna Pietro Paolo , Burton Dennis R. , Crowe James E. , Williamson R. Anthony
Published: May 2007

Human metapneumovirus (hMPV) is a recently discovered paramyxovirus that is a major cause of lower-respiratory-tract disease. hMPV is associated with more severe disease in infants and persons with underlying medical conditions. Animal studies have shown that the hMPV fusion (F) protein alone is capable of inducing protective immunity. Here, we report the use of phage display technology to generate a fully human monoclonal antibody fragment (Fab) with biological activity against hMPV. Phage antibody libraries prepared from human donor tissues were selected against recombinant hMPV F protein with multiple rounds of panning. Recombinant Fabs then were expressed in bacteria, and supernatants were screened by enzyme-linked immunosorbent assay and immunofluorescent assays. A number of Fabs that bound to hMPV F were isolated, and several of these exhibited neutralizing activity in vitro. Fab DS7 neutralized the parent strain of hMPV with a 60% plaque reduction activity of 1.1 μg/ml and bound to hMPV F with an affinity of 9.8 ×10−10M, as measured by surface plasmon resonance. To test the in vivo activity of Fab DS7, groups of cotton rats were infected with hMPV and given Fab intranasally 3 days after infection. Nasal turbinates and lungs were harvested on day 4 postinfection and virus titers determined. Animals treated with Fab DS7 exhibited a >1,500-fold reduction in viral titer in the lungs, with a modest 4-fold reduction in the nasal tissues. There was a dose-response relationship between the dose of DS7 and virus titer. Human Fab DS7 may have prophylactic or therapeutic potential against severe hMPV infection.
A Functional Heat Shock Protein 90 Chaperone Is Essential for Efficient Flock House Virus RNA Polymerase Synthesis in
Drosophila
Cells
Authors: Castorena Kathryn M. , Weeks Spencer A. , Stapleford Kenneth A. , Cadwallader Amy M. , Miller David J.
Published: May 2007

The molecular chaperone heat shock protein 90 (Hsp90) is involved in multiple cellular processes including protein maturation, complex assembly and disassembly, and intracellular transport. We have recently shown that a disruption of Hsp90 activity in cultured
Drosophila melanogaster
cells suppresses Flock House virus (FHV) replication and the accumulation of protein A, the FHV RNA-dependent RNA polymerase. In the present study, we investigated whether the defect in FHV RNA polymerase accumulation induced by Hsp90 suppression was secondary to an effect on protein A synthesis, degradation, or intracellular membrane association. Treatment with the Hsp90-specific inhibitor geldanamycin selectively reduced FHV RNA polymerase synthesis by 80% in
Drosophila
S2 cells stably transfected with an inducible protein A expression plasmid. The suppressive effect of geldanamycin on protein A synthesis was not attenuated by proteasome inhibition, nor was it sensitive to changes in either the mRNA untranslated regions or protein A intracellular membrane localization. Furthermore, geldanamycin did not promote premature protein A degradation, nor did it alter the extremely rapid kinetics of protein A membrane association. These results identify a novel role for Hsp90 in facilitating viral RNA polymerase synthesis in
Drosophila
cells and suggest that FHV subverts normal cellular pathways to assemble functional replication complexes.
Chicken Heat Shock Protein 90 Is a Component of the Putative Cellular Receptor Complex of Infectious Bursal Disease Virus
Authors: Lin Ta-Wei , Lo Chi-Wen , Lai Su-Yuan , Fan Ruey-Jane , Lo Chao-Jung , Chou Yu-mei , Thiruvengadam Rekha , Wang Andrew H.-J. , Wang Min-Ying
Published: May 2007

Infectious bursal disease virus (IBDV) causes a highly contagious disease in young chicks and leads to significant economic losses in the poultry industry. The capsid protein VP2 of IBDV plays an important role in virus binding and cell recognition. VP2 forms a subviral particle (SVP) with immunogenicity similar to that of the IBDV capsid. In the present study, we first showed that SVP could inhibit IBDV infection to an IBDV-susceptible cell line, DF-1 cells, in a dose-dependent manner. Second, the localizations of the SVP on the surface of DF-1 cells were confirmed by fluorescence microscopy, and the specific binding of the SVP to DF-1 cells occurred in a dose-dependent manner. Furthermore, the attachment of SVP to DF-1 cells was inhibited by an SVP-induced neutralizing monoclonal antibody against IBDV but not by denatured-VP2-induced polyclonal antibodies. Third, the cellular factors in DF-1 cells involved in the attachment of SVP were purified by affinity chromatography using SVP bound on the immobilized Ni
2+
ions. A dominant factor was identified as being chicken heat shock protein 90 (Hsp90) (cHsp90) by mass spectrometry. Results of biotinylation experiments and indirect fluorescence assays indicated that cHsp90 is located on the surface of DF-1 cells. Virus overlay protein binding assays and far-Western assays also concluded that cHsp90 interacts with IBDV and SVP, respectively. Finally, both Hsp90 and anti-Hsp90 can inhibit the infection of DF-1 cells by IBDV. Taken together, for the first time, our results suggest that cHsp90 is part of the putative cellular receptor complex essential for IBDV entry into DF-1 cells.
Major Neutralizing Sites on Vaccinia Virus Glycoprotein B5 Are Exposed Differently on Variola Virus Ortholog B6
Authors: Aldaz-Carroll Lydia , Xiao Yuhong , Whitbeck J. Charles , de Leon Manuel Ponce , Lou Huan , Kim Mikyung , Yu Jessica , Reinherz Ellis L. , Isaacs Stuart N. , Eisenberg Roselyn J. , Cohen Gary H.
Published: May 2007

Immunization against smallpox (variola virus) with Dryvax, a live vaccinia virus (VV), was effective, but now safety is a major concern. To overcome this issue, subunit vaccines composed of VV envelope proteins from both forms of infectious virions, including the extracellular enveloped virion (EV) protein B5, are being developed. However, since B5 has 23 amino acid differences compared with its B6 variola virus homologue, B6 might be a better choice for such a strategy. Therefore, we compared the properties of both proteins using a panel of monoclonal antibodies (MAbs) to B5 that we had previously characterized and grouped according to structural and functional properties. The B6 gene was obtained from the Centers for Disease Control and Prevention, and the ectodomain was cloned and expressed in baculovirus as previously done with B5, allowing us to compare the antigenic properties of the proteins. Polyclonal antibodies to B5 or B6 cross-reacted with the heterologous protein, and 16 of 26 anti-B5 MAbs cross-reacted with B6. Importantly, 10 anti-B5 MAbs did not cross-react with B6. Of these, three have important anti-VV biologic properties, including their ability to neutralize EV infectivity and block comet formation. Here, we found that one of these three MAbs protected mice from a lethal VV challenge by passive immunization. Thus, epitopes that are present on B5 but not on B6 would generate an antibody response that would not recognize B6. Assuming that B6 contains similar variola virus-specific epitopes, our data suggest that a subunit vaccine using the variola virus homologues might exhibit improved protective efficacy against smallpox.
Epstein-Barr Virus Induces MCP-1 Secretion by Human Monocytes via TLR2
Authors: Gaudreault Eric , Fiola Stéphanie , Olivier Martin , Gosselin Jean
Published: May 2007

Epstein-Barr virus (EBV) is a gammaherpesvirus infecting the majority of the human adult population in the world. TLR2, a member of the Toll-like receptor (TLR) family, has been implicated in the immune responses to different viruses including members of the herpesvirus family, such as human cytomegalovirus, herpes simplex virus type 1, and varicella-zoster virus. In this report, we demonstrate that infectious and UV-inactivated EBV virions lead to the activation of NF-κB through TLR2 using HEK293 cells cotransfected with TLR2-expressing vector along with NF-κB-Luc reporter plasmid. NF-κB activation in HEK293-TLR2 cells (HEK293 cells transfected with TLR2) by EBV was not enhanced by the presence of CD14. The effect of EBV was abrogated by pretreating HEK293-TLR2 cells with blocking anti-TLR2 antibodies or by preincubating viral particles with neutralizing anti-EBV antibodies 72A1. In addition, EBV infection of primary human monocytes induced the release of MCP-1 (monocyte chemotactic protein 1), and the use of small interfering RNA targeting TLR2 significantly reduced such a chemokine response to EBV. Taken together, these results indicate that TLR2 may be an important pattern recognition receptor in the immune response directed against EBV infection.
Coupled Translation of the Second Open Reading Frame of M2 mRNA Is Sequence Dependent and Differs Significantly within the Subfamily
Pneumovirinae
Authors: Gould Phillip Spencer , Easton Andrew John
Published: May 2007

Coupled translation, first described in the M2 gene of pneumovirus respiratory syncytial virus (RSV), is an alternative mechanism of translational initiation in which the ribosomes which translate the first (M2-1) open reading frame (ORF) move a short distance upstream after termination and reinitiate translation from a second (M2-2) overlapping ORF. Here, we show that the same mechanism occurs in two closely related viruses, avian pneumovirus (APV) and pneumonia virus of mice (PVM), although with markedly different efficiencies. To identify the reasons for the variation in efficiency of coupled expression between RSV and APV, we used chimeric M2-1 genes containing different lengths of the M2-1 ORF from each virus. An essential component allowing coupled expression in the chimeras was a segment from the RSV M2-1 coding region containing a high degree of secondary structure. Additional sequences at the 5′ end of the RSV M2-1 ORF also promoted coupled translation when the region with high levels of secondary structure was present. These data indicate that at least two distant parts of the mRNA transcript, together with a suitable overlapping region, are involved in the coupling process. Replacement of the last 102 nucleotides of the RSV M2-1 ORF with the equivalent APV sequence showed identical levels of coupled translation. Thus, the overlapping region can direct the ribosome back onto the start codon of the second ORF while the upstream coding sequence of the M2-1 ORF determines the levels of coupled expression.
Memory CD4
+
T-Lymphocyte Loss and Dysfunction during Primary Simian Immunodeficiency Virus Infection
Authors: Sun Yue , Permar Sallie R. , Buzby Adam P. , Letvin Norman L.
Published: May 2007

It has long been appreciated that CD4
+
T lymphocytes are dysfunctional in human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV)-infected individuals, and it has recently been shown that HIV/SIV infections are associated with a dramatic early destruction of memory CD4
+
T lymphocytes. However, the relative contributions of CD4
+
T-lymphocyte dysfunction and loss to immune dysregulation during primary HIV/SIV infection have not been fully elucidated. In the current study, we evaluated CD4
+
T lymphocytes and their functional repertoire during primary SIVmac251 infection in rhesus monkeys. We show that the extent of loss of memory CD4
+
T lymphocytes and staphylococcal enterotoxin B-stimulated cytokine production by total CD4
+
T lymphocytes during primary SIVmac251 infection is tightly linked in a cohort of six rhesus monkeys to set point plasma viral RNA levels, with greater loss and dysfunction being associated with higher steady-state viral replication. Moreover, in exploring the mechanism underlying this phenomenon, we demonstrate that the loss of functional CD4
+
T lymphocytes during primary SIVmac251 infection is associated with both a selective depletion of memory CD4
+
T cells and a loss of the functional capacity of the memory CD4
+
T lymphocytes that escape viral destruction.
Expression of Extremely Low Levels of Thymidine Kinase from an Acyclovir-Resistant Herpes Simplex Virus Mutant Supports Reactivation from Latently Infected Mouse Trigeminal Ganglia
Authors: Besecker Michael I. , Furness Caroline L. , Coen Donald M. , Griffiths Anthony
Published: May 2007

A single-cytosine-deletion in the herpes simplex virus gene encoding thymidine kinase (TK) was previously found in an acyclovir-resistant clinical isolate. A laboratory strain engineered to carry this mutation did not generate sufficient TK activity for detection by plaque autoradiography, which detected 0.25% wild-type activity. However, a drug sensitivity assay suggested that extremely low levels of TK are generated by this virus. The virus was estimated to express 0.09% of wild-type TK activity via a ribosomal frameshift 24 nucleotides upstream of the mutation. Remarkably, this appeared to be sufficient active TK to support a low level of reactivation from latently infected mouse trigeminal ganglia.
Pretreatment Sequence Diversity Differences in the Full-Length Hepatitis C Virus Open Reading Frame Correlate with Early Response to Therapy
Authors: Donlin Maureen J. , Cannon Nathan A. , Yao Ermei , Li Jia , Wahed Abdus , Taylor Milton W. , Belle Steven H. , Di Bisceglie Adrian M. , Aurora Rajeev , Tavis John E.
Published: May 2007

Pegylated alpha interferon and ribavirin therapy for hepatitis C virus (HCV) genotype 1 infection fails for half of Caucasian American patients (CA) and more often for African Americans (AA). The reasons for these low response rates are unknown. HCV is highly genetically variable, but it is unknown how this variability affects response to therapy. To assess effects of viral diversity on response to therapy, the complete pretreatment genotype 1 HCV open reading frame was sequenced using samples from 94 participants in the Virahep-C study. Sequences from patients with >3.5 log declines in viral RNA levels by day 28 (marked responders) were more variable than those from patients with declines of <1.4 log (poor responders) in NS3 and NS5A for genotype 1a and in core and NS3 for genotype 1b. These correlations remained when all T-cell epitopes were excluded, indicating that these differences were not due to differential immune selection. When the sequences were compared by race of the patients, higher diversity in CA patients was found in E2 and NS2 but only for genotype 1b. Core, NS3, and NS5A can block the action of alpha interferon in vitro; hence, these genetic patterns are consistent with multiple amino acid variations independently impairing the function of HCV proteins that counteract interferon responses in humans, resulting in HCV strains with variable sensitivity to therapy. No evidence was found for novel HCV strains in the AA population, implying that AA patients may be infected with a higher proportion of the same resistant strains that are found in CA patients.
A Herpes Simplex Virus gD-YFP Fusion Glycoprotein Is Transported Separately from Viral Capsids in Neuronal Axons
Authors: Snyder Aleksandra , Bruun Birgitte , Browne Helena M. , Johnson David C.
Published: May 2007

Two models describing how alphaherpesviruses exit neurons differ with respect to whether nucleocapsids and envelope glycoproteins travel toward axon termini separately or as assembled enveloped virions. Recently, a pseudorabies virus glycoprotein D (gD)-green fluorescent protein fusion was found to colocalize with viral capsids, supporting anterograde transport of enveloped virions. Previous antibody staining experiments demonstrated that herpes simplex virus (HSV) glycoproteins and capsids are separately transported in axons. Here, we generated an HSV expressing a gD-yellow fluorescent protein (YFP) fusion and found that gD-YFP and capsids were transported separately in neuronal axons. Anti-gD antibodies colocalized with gD-YFP, indicating that gD-YFP behaves like wild-type HSV gD.
Varus instability of the hallux interphalangeal joint in a taekwondo athlete
Authors: Gong Hyun Sik , Kim Yeun Ho , Park Moon Seok
Published: May 2007

The hallux interphalangeal joint is stable in the transverse plane and there have been only a few reports of varus instability of this joint. A case is described of varus subluxation of the hallux interphalangeal joint in a taekwondo athlete and the surgical outcome after reconstruction of the collateral ligament. Taekwondo athletes, who require fast powerful kicks, should be warned about this type of forefoot injury.
The role of physical examinations in studies of musculoskeletal disorders of the elbow
Authors: Kryger Ann Isabel , Lassen Christina Funch , Andersen Johan Hviid
Published: May 2007

Objectives:

To present data on pain and physical findings from the elbow region, and to discuss the role of diagnostic criteria in epidemiological studies of epicondylitis.

Methods:

From a cohort of computer workers a subgroup of 1369 participants, who reported at least moderate pain in the neck and upper extremities, were invited to a standardised physical examination. Two independent physical examinations were performedone blinded and one not blinded to the medical history. Information concerning musculoskeletal symptoms was obtained by a baseline questionnaire and a similar questionnaire completed on the day of examination.

Results:

349 participants met the authors criteria for being an arm case and 249 were elbow cases. Among the 1369 participants the prevalence of at least mild palpation tenderness and indirect tenderness at the lateral epicondyle was 5.8. The occurrence of physical findings increased markedly by level of pain score. Only about one half with physical findings fulfilled the authors pain criteria for having lateral epicondylitis. A large part with physical findings reported no pain at all in the elbow in any of the two questionnaires, 28 and 22, respectively. Inter-examiner reliability between blinded and not blinded examination was found to be low kappa value 0.340.40.

Conclusion:

Very few with at least moderate pain in the elbow region met common specific criteria for lateral epicondylitis. The occurrence of physical findings increased markedly by level of pain score and the associations were strongest with pain intensity scores given just before the examination. Physical signs were commonly found in subjects with no pain complaints. No further impact was achieved if the physical examination was not blinded to the medical history. Furthermore, the authors propose that pain, clinical signs and disability are studied as separate outcomes, and that the diagnoses of lateral epicondylitis should be used only for cases with classical signs of inflammation reflected by severe pain, which for example conveys some disability.
Field protection effectiveness of chemical protective suits and gloves evaluated by biomonitoring
Authors: Chang F K , Chen M L , Cheng S F , Shih T S , Mao I F
Published: May 2007

Objectives:

To determine the effectiveness of protective suits and gloves by biomonitoring.

Methods:

Fifteen male spray painters at a ship coating factory were studied for two weeks. Workers wore no protective clothing during the first week and wore protective suits and gloves during the second week. Sampling was conducted on four consecutive working days each week. Ethyl benzene and xylene in the air were collected by using 3M 3500 organic vapour monitors. Urine was collected before and after each work shift.

Results:

Urinary mandelic acid MA and methyl hippuric acid MHA levels were divided by the personal exposure concentrations of ethyl benzene and xylene, respectively. Mean SE corrected MA and MHA concentrations in the first week were 1.07 0.18 and 2.66 0.68 mg/g creatinine/mg/m3, and concentrations in the second week were 0.50 0.12 and 1.76 0.35 mg/g creatinine/mg/m3in the second week, respectively. Both MA and MHA concentrations in the second week when spray painters wore protective suits and gloves were lower than in the first week, respectively p<0.001, p0.011. Mean decrease in MA and MHA biomarkers were 69 and 49, respectively.

Conclusion:

This study successfully evaluated the effectiveness of chemical protective suits and gloves by using biomarkers as urinary MA and MHA. This method is feasible for determining the performance of workers wearing personal protective equipment. Moreover, the experimental results suggest that dermal exposure may be the major contributor to total body burden of solvents in spray painters without protective suits and gloves.
Mineral dust exposure in young Indian adults: an effect on lung growth?
Authors: Green D A , McAlpine G , Semple S , Cowie H , Seaton A
Published: May 2007

Background/objective:

Long-term occupational exposure to mineral dusts including quartz is known to cause pneumoconiosis but little is known about the effects of such exposure during the period of lung development in childhood. The objective of this study was to investigate the effects on young people of exposure to mineral dusts.

Methods:

We carried out a cross-sectional study of a group of 81 Indian stone crushers (average age 21) and a control group of 72 nearby slum dwellers (average age 21) in order to assess dust exposures, respiratory symptoms and lung function.

Results:

Stone crushers’ corrected 8-hour time weighted average concentrations of total inhalable dust, respirable dust and respirable crystalline silica were 143 mg/m3, 39.7 mg/m3and 2.29 mg/m3respectively, which are 14, 10 and 23 times the UK workplace exposure limits, respectively. Both groups also had high exposures to outdoor and general domestic particulate matter. Compared to controls, stone crushers had significantly more symptoms, lower levels of forced vital capacity (FVC) and forced expiratory time (FET) and higher levels of forced expiratory volume in one second (FEV1)/FVC ratio and mid-expiratory flow rate (MEF). There were no differences in FEV1levels. Symptoms and lung function were not associated with time lived on site or time spent in job. A selection of chest radiographs showed no silicosis by International Labour Office (ILO) criteria.

Conclusion:

Individuals exposed to mixed mineral dust in childhood and early adult life had excess symptoms and reduced vital capacity without airflow obstruction compared with control subjects. We interpret this as evidence of stunting of lung growth caused by exposure to respirable dust.
SILICON CARBIDE JUNCTION FIELD EFFECT TRANSISTORS
Authors: STEPHANI DIETRICH , FRIEDRICHS PETER
Published: May 2007

The chapter will give an overview about the theory of JFETs with special attention to the wide band gap issues related to SiC. After a comprehensive discussion of relevant structures and topologies experimental results are presented and discussed. Especially vertical structures are in the focus of this chapter. Characteristic I-V data will be shown as well as application specific solutions regarding the temperature behavior or the ruggedness of the devices. The status of the JFETs technology will be judged and compared to alternative solutions like MOSFEts or lateral JFETs. Finally, an outlook will be given regarding targeted applications for SiC VJFETs and the resulting requirements as targets for future improvements.
Nanostructured ZnO: Building Blocks for Nanoscale Devices
Authors: FAN Z. , LU J. G.
Published: May 2007

ZnO is attracting intensive attention for its versatile applications in transparent electronics, UV emitter, piezoelectric devices, chemical sensor and spin electronics. As one of the direct wide band gap semiconductors, it has advantages over GaN due to its larger exciton binding energy, better lattice match on heteroepitaxial growth and availability of single crystal substrate. Large effort has been invested in the growth of nanostructured ZnO to explore its potentials for nanoscale device applications. ZnO nanobelts, nanowires, nanorings, and nanohelixes demonstrate the diversity of ZnO nanostructures family. This review presents recent research on ZnO nanostructures. Issues of synthesis methods, optical, electrical, gas sensing and magnetic properties are summarized. These progresses constitute the basis for developing future applications in nanoscale electronics, optoelectronics, chemical sensor and spintronics.
CARBON NANOTUBE FIELD-EFFECT TRANSISTORS
Authors: GUO JING , KOSWATTA SIYURANGA O. , NEOPHYTOU NEOPHYTOS , LUNDSTROM MARK
Published: May 2007

This paper discusses the device physics of carbon nanotube field-effect transistors (CNTFETs). After reviewing the status of device technology, we use results of our numerical simulations to discuss the physics of CNTFETs emphasizing the similarities and differences with traditional FETs. The discussion shows that our understanding of CNTFET device physics has matured to the point where experiments can be explained and device designs optimized. The paper concludes with some thoughts on challenges and opportunities for CNTFET electronics.