Response of crayfish, Procambarus clarkii, haemocytes infected by white spot syndrome virus

White spot syndrome virus ( WSSV) is a serious pathogen of aquatic crustaceans. Little is known about its transmission in vivo and the immune reaction of its hosts. In this study, the circulating haemocytes of crayfish, Procambarus clarkii, infected by WSSV, and primary haemocyte cultures inoculated with WSSV, were collected and observed by transmission electron microscopy and light microscopy following in situ hybridization. In ultrathin sections of infected haemocytes, the enveloped virions were seen to be phagocytosed in the cytoplasm and no viral particles were observed in the nuclei. In situ hybridization with WSSV-specific probes also demonstrated that there were no specific positive signals present in the haemocytes. Conversely, strong specific positive signals showed that WSSV replicated in the nuclei of gill cells. As a control, the lymphoid organ of shrimp, Penaeus monodon, infected by WSSV was examined by in situ hybridization which showed that WSSV did not replicate within the tubules of the lymphoid organ. In contrast to previous studies, it is concluded that neither shrimp nor crayfish haemocytes support WSSV replication.White spot syndrome virus (WSSV) is a serious pathogen of aquatic crustaceans. Little is known about its transmission in vivo and the immune reaction of its hosts. In this study, the circulating haemocytes of crayfish, Procambarus clarkii, infected by WSSV, and primary haemocyte cultures inoculated with WSSV, were collected and observed by transmission electron microscopy and light microscopy following in situ hybridization. In ultra-thin sections of infected haemocytes, the enveloped virions were seen to be phagocytosed in the cytoplasm and no viral particles were observed in the nuclei. In situ hybridization with WSSV-specific probes also demonstrated that there were no specific positive signals present in the haemocytes. Conversely, strong specific positive signals showed that WSSV replicated in the nuclei of gill cells. As a control, the lymphoid organ of shrimp, Penaeus monodon, infected by WSSV was examined by in situ hybridization which showed that WSSV did not replicate within the tubules of the lymphoid organ. In contrast to previous studies, it is concluded that neither shrimp nor crayfish haemocytes support WSSV replication.

Intra-colonial response to Acroporid "White syndrome" lesions in tabular Acropora spp. (Scleractinia)

'White syndrome' is considered to be the most prevalent coral disease on the Great Barrier Reef, characterised by rapid rates of lesion progression and high levels of colony mortality. This study investigated the production and translocation of photoassimilates towards white syndrome lesions (WSLs) and artificially inflicted lesions in healthy and diseased colonies of tabular Acropora spp. to determine the intra-colonial response to white syndrome using C-14 labelling. Translocation of C-14 labelled photoassimilates was preferentially orientated away from active WSLs, with minimal C-14 activity observed in the lesion borders, whilst artificial lesions (ALs) created directly opposite WSL borders showed significantly higher C-14 activity, suggesting active translocation of photoassimilates for tissue regeneration. Transport of photoassimilates in healthy coral colonies was preferentially oriented towards ALs with a higher perimeter-area ratio, although translocation towards WSL boundaries was minimal even though the lesion perimeter was often the width of the colony (> 200 cm). We suggest that the preferential orientation of photoassimilates away from WSLs may represent a deliberate strategy by the colony to induce a 'shutdown reaction' in order to preserve intra-colonial resources within areas of the colony that are more likely to survive and recover.

Phototrophic microendoliths bloom during coral "white syndrome"

Following rapid lesion progression of white syndrome in tabular Acropora spp., the white bare skeleton gradually changes to green, a result of endolithic algae blooms (primarily Ostreobium spp.). Endolithic algal biomass and chlorophyll concentration were found to be an order of magnitude higher in the green zone compared with healthy appearing parts of each colony. Chl b to Chl a ratio increased from 1:1.6 in the healthy area to 1:2 and 1:3.5 in the white exposed skeleton and green zones, respectively. These observations together with pulse amplitude modulated (PAM) fluorometry suggest photoacclimation of the endoliths in the green zone. Histopathological microscopy revealed that the endolithic algal filaments penetrate the coral tissue. This study highlights the interaction of endolithic algae with both the skeleton and host tissue. This may have a critical role in the processes that accompany the post-disease state in reef-building corals.

Longitudinal excursion and strain in the median nerve during novel nerve gliding exercises for carpal tunnel syndrome

Nerve and tendon gliding exercises are advocated in the conservative and postoperative management of carpal tunnel syndrome (CTS). However, traditionally advocated exercises elongate the nerve bedding substantially, which may induce a potentially deleterious strain in the median nerve with the risk of symptom exacerbation in some patients and reduced benefits from nerve gliding. This study aimed to evaluate various nerve gliding exercises, including novel techniques that aim to slide the nerve through the carpal tunnel while minimizing strain (sliding techniques). With these sliding techniques, it is assumed that an increase in nerve strain due to nerve bed elongation at one joint (e.g., wrist extension) is simultaneously counterbalanced by a decrease in nerve bed length at an adjacent joint (e.g., elbow flexion). Excursion and strain in the median nerve at the wrist were measured with a digital calliper and miniature strain gauge in six human cadavers during six mobilization techniques. The sliding technique resulted in an excursion of 12.4 mm, which was 30% larger than any other technique (p 0.0002). Strain also differed between techniques (p 0.00001), with minimal peak values for the sliding technique. Nerve gliding associated with wrist movements can be considerably increased and nerve strain substantially reduced by simultaneously moving neighboring joints. These novel nerve sliding techniques are biologically plausible exercises for CTS that deserve further clinical evaluation. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:972-980, 2007

Street elevation, White Residence, Brisbane

South-west elevation, as seen from street.

What are the economic prospects of developing aquaculture in Queensland to supply the low price white fillet market? Lessons from the US channel catfish industry

The farming of channel catfish (Ictalurus punctatus) is the largest (by volume and value) and most successful (in terms of market impact) aquaculture industry in the United States of America. Farmed channel catfish is the most consumed (in terms of volume per capita) fish fillet in the U.S. market. Within Australia, it has long been suggested by researchers and industry that silver perch (Bidyanus bidyanus) and possibly other endemic teraponid species possess similar biological attributes for aquaculture as channel catfish and may have the potential to generate a similar industry. The current teraponid industry in Australia, however, shows very little resemblance to the catfish industry, either in production style or market philosophy. A well established budget framework from the literature on U.S. channel catfish farming has been adapted for cost and climate conditions of the Burdekin region, Queensland, Australia. Breakeven prices for the hypothetical teraponid farms were found to be up to 50% higher than those published for catfish farms however were much lower than those reported for silver perch production in Australia using current, endemic styles of production. The breakeven prices for the hypothetical teraponid farms were most sensitive (in order of significance) to feed prices, production rates, interest rates, fingerling prices and electricity prices. At equivalent feed costs the costs of production between the hypothetical catfish farms in the Mississippi, U.S. and the hypothetical teraponid farms in the Burdekin, Australia were remarkably similar. The cost of feeds suitable for teraponid production in Australia are currently around double that of catfish feeds in the U.S. Issues currently hindering the development of a large scale teraponid industry in Australia are discussed.

The contribution of classical (beta(1/2)-) and atypical beta-adrenoceptors to the stimulation of human white adipocyte lipolysis and right atrial appendage contraction by novel beta(3)-adrenoceptor agonists of differing selectivities

The role of beta(3)- and other putative atypical beta-adrenaceptors in human white adipocytes and right atrial appendage has been investigated using CGP 12177 and novel phenylethanolamine and aryloxypropanolamine beta(3)-adrenoceptor (beta(3)AR) agonists with varying intrinsic activities and selectivities for human cloned PAR subtypes. The ability to demonstrate beta(1/2)AR antagonist-insensitive (beta(3) or other atypical beta AR-mediated) responses to CGP 12177 was critically dependent on the albumin batch used to prepare and incubate the adipocytes. Four aryloxypropanolamine selective beta(3)AR agonists (SB-226552, SB-229432, SB-236923, SB-246982) consistently elicited beta(1/2)AR antagonist-insensitive lipolysis. However, a phenylethanolamine (SB-220646) that was a selective full beta(3)AR agonist elicited full lipolytic and inotropic responses that were sensitive to beta(1/2)AR antagonism, despite it having very low efficacies at cloned beta(1)- and beta(2)ARs. A component of the response to another phenylethanolamine selective beta(3)AR agonist (SB-215691) was insensitive to beta(1/2)AR antagonism in some experiments. Because novel aryloxypropanolamine had a beta(1/2)AR antagonist-insensitive inotropic effect, these results establish more firmly that beta(3)ARs mediate lipolysis in human white adipocytes, and suggest that putative 'beta(4)ARs' mediate inotropic responses to CGP 12177. The results also illustrate the difficulty of predicting from studies on cloned beta ARs which beta ARs will mediate responses to agonists in tissues that have a high number of beta(1)- and beta(2)ARs or a low number of beta(3)ARs.