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OBJECTIVE: The purpose of the paper was to explore the relationship between herpes zoster and pyogenic liver abscesses in Taiwan. METHODS: This was a nationwide cohort study. Using the database of the Taiwan National Health Insurance Program, there were 33049 subjects aged 20-84 years who were newly diagnosed with herpes zoster from 1998 to 2010 that were selected for our study, and they were our herpes zoster group. 131707 randomly selected subjects without herpes zoster were our non-herpes zoster group. Both groups were matched by sex, age, other comorbidities, and the index year of their herpes zoster diagnosis. The incidence of pyogenic liver abscesses at the end of 2011 was then estimated. The multivariable Cox proportional hazard regression model was used to estimate the hazard ratio and 95% confidence interval for pyogenic liver abscesses associated with herpes zoster and other comorbidities. RESULTS: The overall incidence rate was 1.38-fold higher in the herpes zoster group than in the non-herpes zoster group (4.47 vs. 3.25 per 10000 person-years, 95% confidence interval 1.32, 1.44). After controlling for potential confounding factors, the adjusted hazard ratio of pyogenic liver abscesses was 1.34 in the herpes zoster group (95% confidence interval 1.05, 1.72) when compared with the non-herpes zoster group. Sex (in this case male), age, presence of biliary stones, chronic kidney diseases, chronic liver diseases, cancers, and diabetes mellitus were also significantly associated with pyogenic liver abscesses. CONCLUSIONS: Patients with herpes zoster are associated with an increased hazard of developing pyogenic liver abscesses.
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Nonuniform ac (alternating current) electric fields created by microelectrodes are investigated for their influence on the transport of the vesicular stomatitis virus (VSV) from aqueous suspensions of physiological ionic strength to surfaces on which the VSV is captured. Whereas passive diffusion did not lead to detectable levels of virus captured on a surface when using titers of VSV as high as 107 PFU/mL, nonuniform electric field-mediated transport led to the detection of 105 PFU/mL of virus in 2 min. An order-of-magnitude analysis of the time scales associated with virus transport to the microelectrodes inside media of physiological relevance indicates that electrothermal fluid flow (and the resulting viscous drag forces on the virus) rather than dielectrophoresis likely constitutes the major mechanism for virus transport far from the electrodes. The influence of dielectrophoresis was calculated to be confined to a region within a few micrometers of the electrodes and to lead to collection patterns of both virus and fluorescently labeled particles near the electrodes that were found to be in qualitative agreement with experiments. These observations and conclusions are discussed within a theoretical framework presented in the paper. The results presented in this work, when combined, suggest that ac electrokinetic phenomena can be used to expeditiously transport and capture viruses onto surfaces from solutions of high ionic strength, thus providing a potentially useful approach to addressing a bottleneck in the development of devices that allow for rapid sampling and detection of infectious biological agents.
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Microfluídica , Virus de la Estomatitis Vesicular Indiana/química , Electroquímica , Iones/química , MicroelectrodosRESUMEN
The ordering of synthetic liquid crystals near surfaces is known to be dependent on the nanoscopic structure and chemical functionality of surfaces. In this letter, we report that the orientational ordering of synthetic liquid crystals on surfaces decorated with viruses is also dependent on the structures of the viruses. Each of the four virions investigated had diameters of approximately 100 nm, but three of the viruses (influenza virus, La Crosse virus, and vesicular stomatitis virus) were enveloped in a lipid bilayer, whereas one virus (adenovirus) was not. We observed that lipid bilayer-enveloped viruses induce homeotropic (perpendicular) ordering of a nematic liquid crystal upon contact with the liquid crystal. In contrast, nonenveloped virus (adenovirus)-treated surfaces caused a near-planar orientation of the liquid crystal. We conclude that the homeotropic ordering of liquid crystals is a signature of the presence of enveloped viruses present on surfaces. These results suggest new approaches to the design of nanostructured materials that incorporate viruses as well as suggest methods that can be used to amplify the presence of nanoscopic virions into micrometer-sized domains of liquid crystal that can be optically probed.
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Adenoviridae/química , Cristales Líquidos/química , Virus ARN/química , Virus La Crosse/química , Orthomyxoviridae/química , Virus de la Estomatitis Vesicular Indiana/químicaRESUMEN
We report a study that investigates the biocompatibility of materials that form lyotropic liquid crystals (LCs) with viruses and mammalian cells that support the replication of viruses. This study is focused on aqueous solutions of tetradecyldimethyl-amineoxide (C(14)AO) and decanol (D), or disodium cromoglycate (DSCG; C(23)H(14)O(11)Na(2)), which can form optically birefringent, liquid crystalline phases. The influence of these materials on the ability of vesicular stomatitis virus (VSV) to infect human epitheloid cervical carcinoma (HeLa) cells was examined by two approaches. First, VSV was dispersed in aqueous C(14)AO+ D or DSCG, and then HeLa cells were inoculated by contacting the cells with the aqueous C(14)AO + D or DSCG containing VSV. The infectivity of VSV to the HeLa cells was subsequently determined. Second, VSV was incubated in LC phases of either C(14)AO + D or DSCG for 4 h, and the concentration (titer) of infectious virus in the LC was determined by dilution into cell culture medium and subsequent inoculation of HeLa cells. Using these approaches, we found that the LC containing C(14)AO + D caused inactivation of virus as well as cell death. In contrast, we determined that VSV retained its infectivity in the presence of aqueous DSCG, and that greater than 74-82% of the HeLa cells survived contact with aqueous DSCG (depending on concentration of DSCG). Because VSV maintained its function (and we infer structure) in LCs formed from DSCG, we further explored the influence of the virus on the ordering of the LC. Whereas the LC formed from DSCG was uniformly aligned on surfaces prepared from self-assembled monolayers (SAMs) of HS(CH(2))(11)(OCH(2)CH(2))(4)OH on obliquely deposited films of gold in the absence of VSV, the introduction of 10(7)-10(8) infectious virus particles per milliliter caused the LC to assume a non-uniform orientation and a colorful appearance that was readily distinguished from the uniformly aligned LCs. Control experiments using cell lysates with equivalent protein concentrations but no virus did not perturb the uniform alignment of the LC.
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Materiales Biocompatibles/química , Cristalización/métodos , Virus de la Estomatitis Vesicular Indiana/crecimiento & desarrollo , Virus de la Estomatitis Vesicular Indiana/ultraestructura , Cultivo de Virus/métodos , Replicación Viral/fisiología , Células HeLa , Humanos , Ensayo de Materiales , SolucionesRESUMEN
Flock house virus (FHV) is a non-enveloped, positive-sense RNA virus of insect origin that belongs to the family Nodaviridae. FHV has been shown to overcome the kingdom barrier and to replicate in plants, insects, yeast and mammalian cells. Although of insect origin, FHV has not previously been shown to replicate in mosquitoes. We have tested FHV replication in vitro in C6/36 cells (derived from neonatal Aedes albopictus) and in vivo in four different genera of mosquitoes, Aedes, Culex, Anopheles and Armigeres. FHV replicated to high titres in C6/36 cells that had been subcloned to support maximum growth of FHV. When adult mosquitoes were orally fed or injected with the virus, FHV antigen was detected in various tissues and infectious virus was recovered. Vectors developed from an infectious cDNA clone of a defective-interfering RNA, derived from FHV genomic RNA2, expressed green fluorescent protein in Drosophila cells and adult mosquitoes. This demonstrates the potential of FHV-based vectors for expression of foreign genes in mosquitoes and possibly other insects.