Pathology and hematology of the Caribbean spiny lobster experimentally infected with Panulirus argus virus 1 (PaV1).

We examined the histopathological and hematological response of the Caribbean spiny lobster to experimentally induced infections with Panulirus argus Virus 1 (PaV1). The fixed phagocytes in the hepatopancreas were the primary sites of PaV1 infection in spiny lobsters. Fixed phagocytes were activated in early infections. However, as the disease progressed, the fixed phagocytes became infected and eventually lysed. Infected cells were subsequently observed in the hepatopancreas, gill, heart, hindgut, glial cells around the ventral nerves, and in the cuticular epidermis and foregut. In advanced infections, spongy connective tissues were heavily infected, as were glial cells around the optic nerves. The structure of the hepatopancreas was significantly altered as the disease progressed. The hemal sinuses among the hepatopancreatic tubules filled with massive amounts of cellular aggregates, including infected circulating hemocytes and spongy connective tissues. Atrophy of the hepatopancreatic tubules occurred in the late stage of viral infection. The virus caused significant decreases in total hemocyte counts and significantly altered several constituents in the hemolymph lysates of diseased lobsters, including: glucose, phosphorus, and triglycerides.

Detection of Panulirus argus Virus 1 in Caribbean spiny lobsters.

Panulirus argus Virus 1 (PaV1) is a pathogenic virus that infects Caribbean spiny lobsters P. argus in the Florida Keys. We have developed a PCR detection assay for PaV1 for the purpose of studying the natural history of the virus and for monitoring the prevalence of infection. The detection of the virus in hemolymph and other tissues is based on the PCR amplification of a 499 bp product using specific primers designed from a cloned fragment of the PaV1 genome. The sensitivity limit for the assay was 1.2 fg of purified viral DNA. The PaV1 primers did not react with lobster DNA, oyster DNA, Ostreid Herpesvirus 1, or murine cytomegalovirus. Using this assay, we successfully followed the course of infection in lobsters inoculated with PaV1 and we detected infections in wild-caught lobsters from the Florida Keys. We have also established guidelines for interpreting infection results from the PCR assay for PaV1.

Detection of Panulirus argus Virus 1 (PaVI) in the Caribbean spiny lobster using fluorescence in situ hybridization (FISH).

Panulirus argus Virus 1 (PaV1) is the first virus known to be pathogenic to a wild lobster. It infects the Caribbean spiny lobster P. argus from the Florida Keys, and has a predilection for juveniles. The monitoring of the virus in wild populations and study of its behavior in the laboratory require the development of reliable diagnostic tools. A sensitive and specific fluorescence in situ hybridization (FISH) assay was developed for detection of PaV1. The lower detection limit using a 110 bp DNA probe in a dot-blot hygridization for PaV1 DNA was 10 pg of cloned template PaV1 DNA and 10 ng of genomic DNA extracted from the hemolymph of diseased spiny lobster. The fluorescein (FITC)-labeled probe specifically hybridized to PaVl-infected cells in the hepatopancreas, hindgut, gills, heart, foregut, and nerve tissues. FITC staining was observed around the inner periphery of the nuclear membrane, with lighter staining in a more dispersed pattern within the nucleus. The probe did not hybridize with host tissues of uninfected spiny lobsters, nor did it cross-react with 4 other virus samples tested. This assay will facilitate our understanding of the pathogenesis of the viral disease and help in monitoring efforts directed at determining the prevalence of PaV1 in juvenile nurseries for this lobster.

An arthropod defensin expressed by the hemocytes of the American dog tick, Dermacentor variabilis (Acari: Ixodidae).

Both soluble and cell-mediated components are involved in the innate immune response of arthropods. Injection of Borrelia burgdorferi, the Lyme disease agent, results in the secretion of defensin into the hemolymph of the ixodid tick, Dermacentor variabilis. The presence of the peptide is observed as early as 15 min post-challenge and remains present through 18 h post-challenge. As observed in insects and soft ticks, the transcript for defensin is detected as early as 1 h post-challenge in D. variabilis. RT-PCR resulted in an amplicon of 624 bp with a 225 bp region that translates to a 74 amino acid preprodefensin. The defensin encoding region was amplified, cloned and sequenced from the hemocytes. It appears as though defensin is stored in the granulocytes of the hemolymph and secreted into the hemolymph upon bacterial insult. The role of defensin as a contributing factor in determining vector competency is discussed.

Bisphenol A blood and saliva levels prior to and after dental sealant placement in adults.

PURPOSE: This study examined the effects of a widely used (Delton Pit & Fissure Sealant - Light Cure Opaque, DENTSPLY Professional, York, PA) pit and fissure sealant material on bisphenol A (BPA) levels in blood and saliva, among both low and high-dose groups over time. METHODS: A convenience sample of 30 adults from the Old Dominion University population were randomly and evenly divided into 2 independent variable groups: a low-dose group (1 occlusal sealant application) and high-dose group (4 occlusal sealant applications). A 2 group, time series design was used to examine the presence and concentration of BPA in serum and saliva after sealant placement. Differences comparing low-dose and high-dose groups were examined 1 hour prior (baseline), 1 hour post, 3 hours post and 24 hours after sealant placement, as measured by a direct-competitive BPA Enzyme Linked ImmunoSorbent Assay (ELISA). Hypothesized outcomes were evaluated by applying a parametric, 2 way ANOVA for repeated measures technique to data on the 30 participants ranging in age from 18 to 40 years, and were of mixed gender and ethnicity. RESULTS: BPA was detected in the saliva of all participants prior to sealant placement and ranged from 0.07 to 6.00 ng/ml at baseline. Salivary BPA concentration levels peaked over a 3 hour period following sealant placement and returned to baseline levels within 24 hours. BPA was significantly elevated at all post-sealant placement time periods for both the low-dose (1 occlusal sealant application) and high-dose (4 occlusal sealant applications) groups with peak levels of 3.98 ng/ml and 9.08 ng/ml, respectively. The blood serum did not contain BPA at any point in this investigation. CONCLUSIONS: Exposure to BPA from sources other than dental resins contributes to salivary baseline concentration levels and indicates environmental exposure and use of products containing BPA. Use of specific molecular formulations of dental sealant material determines the release of BPA, therefore, dental sealant materials should be reviewed independently when questioning the release of BPA from dental sealants. In addition, dosage amounts of the dental sealant material used in this study do not influence the serum concentration levels of BPA. Further research is needed to examine the cumulative estrogenic effects of BPA from dental sealants.