Domesticated cats can be infected with highly pathogenic avian influenza H5N1 virus and potentially can be vector or reservoir hosts in an influenza pandemic. We examined the immunogenicity of the ...hemagglutinin (HA) of H5N1strain VN/1203/04 in cats. ELISAs showed that a single dose of recombinant H5 HA protein can induce a robust antibody response against both whole inactivated virus and recombinant HA antigen. A marked increase in hemagglutination inhibition (HI) titers was also observed in sera from cats given a single dose of the H5 HA protein. However, cats given the commercial H5N1 vaccine required 2 doses before increased H5 HA‐specific antibody titers were observed. Despite boosting, cats receiving the commercial H5N1 vaccine had HI titers lower than those given one injection of recombinant protein. Cats vaccinated with plasmid DNA encoding HA failed to develop HA‐specific antibody responses. Finally, sera from cats that received the protein vaccine neutralized wild type H5N1 influenza virus (VN/120304). The results of this study indicate that recombinant H5 HA protein‐based vaccines may be more effective that either inactivated influenza virus or DNA vaccines in cats.
Burkholderia mallei is a highly pathogenic bacterium that causes the zoonosis glanders. Previous studies indicated that the genome of the organism contains eight genes specifying autotransporter ...proteins, which are important virulence factors of Gram-negative bacteria. In the present study, we report the characterization of one of these autotransporters, BpaB. Database searches identified the bpaB gene in ten B. mallei isolates and the predicted proteins were 99-100% identical. Comparative sequence analyses indicate that the gene product is a trimeric autotransporter of 1,090 amino acids with a predicted molecular weight of 105-kDa. Consistent with this finding, we discovered that recombinant bacteria expressing bpaB produce a protein of greater than or equal to 300-kDa on their surface that is reactive with a BpaB-specific monoclonal antibody. Analysis of sera from mice infected with B. mallei indicated that animals produce antibodies against BpaB during the course of disease, thus establishing production of the autotransporter in vivo. To gain insight on its role in virulence, we inactivated the bpaB gene of B. mallei strain ATCC 23344 and determined the median lethal dose of the mutant in a mouse model of aerosol infection. These experiments revealed that the bpaB mutation attenuates virulence 8-14 fold. Using a crystal violet-based assay, we also discovered that constitutive production of BpaB on the surface of B. mallei promotes biofilm formation. To our knowledge, this is the first report of a biofilm factor for this organism.
The present study was undertaken to evaluate the underlying mechanism(s) by which PR and a Krüppel-like family member, basic transcription element binding protein (BTEB1), mediate endometrial ...epithelial expression of pregnancy-associated genes. Human endometrial carcinoma cell lines (Hec-1-A) expressing high and low levels of BTEB1 were transiently transfected with a human PR isoform (PR-B) expression construct and a luciferase reporter gene driven by the uteroferrin gene promoter that is responsive to both BTEB1 and the PR ligand progesterone. Unliganded PR inhibited luciferase activity in low and high BTEB backgrounds, and this effect was reversed by the synthetic progestin R5020 in both lines. Transactivation by PR of uteroferrin promoter activity (approximately 4-fold) was maximal at lower R5020 concentrations (10 nM) in endometrial cells with higher BTEB1 expression, suggesting that nuclear BTEB1content influenced target gene promoter sensitivity to progesterone. BTEB1 and PR-B were found to physically interact in a progesterone-independent manner, using a coimmunoprecipitation assay that employed antibodies specific to either protein. Moreover, the formation of the BTEB1/PR complex, independent of progesterone, occurred within the context of uterine endometrial proteins and was diminished in late-pregnancy endometrium. Mammalian two-hybrid assays using the entire open reading frame of BTEB1 and/or PR-B fused to either the GAL4 DNA-binding domain or VP16 activation domain and a reporter gene (pG5CAT) under the control of GAL4-binding sites were used to evaluate the formation of functional PR-B/BTEB1 dimer in Cos-1 cells. GAL4/PR-B and VP16/PR-B induced ( approximately 3- to 4-fold) chloramphenicol acetyltransferase (CAT) activity in a progesterone-dependent manner, suggesting PR-dimer formation. By contrast, VP16/PR-B and GAL4/BTEB1 had no effect on basal CAT activity. The combination of VP16- and GAL4-PR-B fusion proteins with the BTEB1 expression construct, pCDNA3-BTEB1 enhanced ligand-bound PR-mediated CAT activity by approximately 3-fold. In transient cotransfection assays using the CAT reporter gene driven by the mouse mammary tumor virus-long terminal repeat promoter, which is responsive to ligand-bound PR but not BTEB1, BTEB1 increased PR-B-mediated CAT activity in a progesterone-dependent manner, consistent with a BTEB1/PR-dimer complex occurring independent of BTEB1 binding to DNA. Unliganded PR-B disrupted the DNA-binding activity of BTEB1 in gel retardation assays, and this effect was enhanced by the presence of PR ligand. Together, these findings support the conclusion that BTEB1 and PR-B are coregulatory proteins that mediate progesterone responsiveness of target genes by direct interactions, leading to the formation of a functional BTEB1/PR-dimer complex.
Thermoregulation in sports is an essential aspect for performance as well as thermal comfort especially in endurance sports such as cycling. During a lot of cycling activities athletes often wearing ...a backpack. Due to the limited air flow channels of conventional backpack systems there is potential to optimize the thermal comfort of cycling backpack. The present subject study rshould compare two new rear panel designs with a conventional full contact back regarding temperature and humidity related to microclimate and interlayer climate. Four male sport students performed a load profile of 30 min. cycling on a Tacx cycling trainer at a moderate intensity level of 130W. Temperature and humidity were measured with combi sensors (SHT25, Sensirion, Switzerland) and stored with a mobile data logger (MSR147WD, MSR Electronics GmbH, Switzerland). The results of the pilot study clearly illustrate the potential of the two newly developed rear panel designs to improve the convective heat transfer during cycling. Depending on the backpack design the headwind during cycling can be used to enhance the thermal comfort of athletes.
Approximately 13% skiers and 38% snowboarders wore wearing a back protector during the last season in Switzerland. This huge number suggests an ensured functionality of such back protectors. However, ...there is no specific standard regarding snow sports available. Therefore, the main goal of the study was to get an initial overview about the functionality in terms of potential protective effects of back protectors. The whole project was divided into an athlete survey and an experimental performance test (drop test). The results from the surveys clearly pointed out, that back protectors belong to the most important pieces of protection equipment in snow sports. The related customer expectations emphasize the importance in terms of injury prevention particularly regarding severe spinal column injuries. Concerning the performance test according to the standard for motorcyclists’ back protectors EN 1621-2 most of the samples did pass protection level 1. However, considering the test procedure there appears to be a mismatch between customer expectations, injury occurrence and the actual preventive potential of currently available protectors.
Burkholderia pseudomallei, the etiologic agent of melioidosis, is a saprophytic bacterium readily isolated from wet soils of countries bordering the equator. Burkholderia mallei is a host-adapted ...clone of B. pseudomallei that does not persist outside of its equine reservoir and causes the zoonosis glanders, which is endemic in Asia, Africa, the Middle East and South America. Infection by these organisms typically occurs via percutaneous inoculation or inhalation of aerosols, and the most common manifestation is severe pneumonia leading to fatal bacteremia. Glanders and melioidosis are difficult to diagnose and require prolonged antibiotic therapy with low success rates. There are no vaccines available to protect against either Burkholderia species, and there is concern regarding their use as biological warfare agents given that B. mallei has previously been utilized in this manner. Hence, experiments were performed to establish a mouse model of aerosol infection to study the organisms and develop countermeasures. Using a hand-held aerosolizer, BALB/c mice were inoculated intratracheally with strains B. pseudomallei 1026b and B. mallei ATCC23344 and growth of the agents in the lungs, as well as dissemination to the spleen, were examined. Mice infected with 102, 103 and 104 organisms were unable to control growth of B. mallei in the lungs and bacteria rapidly disseminated to the spleen. Though similar results were observed in mice inoculated with 103 and 104 B. pseudomallei cells, animals infected with 102 organisms controlled bacterial replication in the lungs, dissemination to the spleen, and the extent of bacteremia. Analysis of sera from mice surviving acute infection revealed that animals produced antibodies against antigens known to be targets of the immune response in humans. Taken together, these data show that small volume aerosol inoculation of mice results in acute disease, dose-dependent chronic infection, and immune responses that correlate with those seen in human infections.
We present a comparative visualization of the acoustic simulation results obtained by two different approaches that were combined into a single simulation algorithm. The first method solves the wave ...equation on a volume grid based on finite elements. The second method, phonon tracing, is a geometric approach that we have previously developed for interactive simulation, visualization and modeling of room acoustics. Geometric approaches of this kind are more efficient than FEM in the high and medium frequency range. For low frequencies they fail to represent diffraction, which on the other hand can be simulated properly by means of FEM. When combining both methods we need to calibrate them properly and estimate in which frequency range they provide comparable results. For this purpose we use an acoustic metric called gain and display the resulting error. Furthermore we visualize interference patterns, since these depend not only on diffraction, but also exhibit phase-dependent amplification and neutralization effects
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