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Catchability is often a key source of uncertainty with any stock assessment, but especially for burrowing species, as their emergent behaviour is often poorly understood. Quantification of catchability will provide a major step towards improvements in the assessment for many species. Scampi (Metanephrops challengeri) are widely distributed around New Zealand, and as with Nephrops (Norway lobster), they occupy burrows in muddy substrate, and are exploited through trawl fisheries, but are only available to these fisheries when emerged on the seabed. Burrow emergence is known to vary over daily and longer cycles. Uncertainty over trawl catchability associated with emergence patterns has led to the development of photographic survey approaches for scampi, based on the counts of burrows. Both survey approaches require an understanding of burrow occupancy and emergence rates to estimate trawl/photo survey catchability, which is a key source of uncertainty. We used acoustic tagging to examine levels of and patterns in the emergence of Metanephrops, using hydrophone receivers moored close to the seabed. Strong emergence cycles were apparent in relation to tidal current (higher emergence with inshore water flow across the slope) and time of day (peaking just after dawn). These data have subsequently been used within a length-based stock assessment of New Zealand scampi, which uses emergence data in conjunction with burrow and animal counts from photographic surveys, for the first time, to inform priors for trawl (mean 0.094) and photographic (mean 0.46) survey catchability, and for burrow occupancy (mean 49.3%). [ABSTRACT FROM AUTHOR]

Background The kidney is an important organ for maintaining blood pressure. We have previously reported that transplanted metanephroi can reproduce some kidney functions. The aim of the present study was to determine the metabolic function of transplanted metanephroi with particular reference to maintaining blood pressure. Methods Male Wistar rats were transplanted with metanephroi (transplanted group, n = 28), following unilateral nephrectomy. For comparison, we performed unilateral nephrectomy without transplantation in 32 rats (non-transplanted group, n = 18; haeminephrectomy control group, n = 14). The remaining kidney was removed 2 weeks after the initial operation, while control rats had a sham operation. Hypotension was induced by intravenous infusion of diltiazem hydrochloride or rapid withdrawal of blood. Mean arterial blood pressure (MAP) was invasively monitored and plasma renin activity (PRA) was analysed at multiple time points. Renin expression by metanephroi was evaluated by real-time polymerase chain reaction and immunohistochemistry. Results Metanephroi in the transplanted group expressed renin messenger RNA. Metanephros transplantation significantly raised PRA and maintained MAP compared with the non-transplanted group. No significant differences between the transplanted and control groups were found with respect to PRA or MAP. PRA was positively correlated with metanephroi weight as well as MAP in the transplanted group. Conclusion The present study shows that transplantation of metanephroi produces PRA and contributes to raising MAP in a rat model of acute hypotension. [ABSTRACT FROM PUBLISHER]

Objective: To define the test characteristics of an enzyme immunoassay (EIA) for plasma-free metanephrines (metanephrine and normetanephrine) in the diagnosis of pheochromocytoma and paraganglioma. Design: Prospective observational design from a single University Hospital. Twenty-four hour urine for catecholamines and plasma for free metanephrines were collected from patients with a clinical suspicion of pheochromocytoma or paraganglioma. Patient records were reviewed for clinical data, follow-up, imaging and laboratory results to establish or exclude the diagnosis of pheochromocytoma. Patients and methods: Out of 178 consecutive patients, 10 had a paraganglioma and 12 had a pheochromocytoma: 156 were finally judged not to harbour active tumors and were therefore considered as controls. The main outcome measure was the diagnosis or exclusion of paraganglioma or pheochromocytoma and test characteristics of plasma-free metanephrines measured by EIA. Results: Urinary epinephrine had a sensitivity of 45.5% and norepinephrine a sensitivity of 75% (98.8% specificity) for the diagnosis of pheochromocytoma. Plasma-free metanephrine and normetanephrine both had a sensitivity of 66.7% and a specificity of 100%, but when combined (either positive) they demonstrated a 91.7% sensitivity with a preserved specificity of 100%. For the diagnosis of paraganglioma, urinary norepinephrine gave slightly better results than plasma-free metanephrines, but combined testing was of no additional value. Conclusions: Plasma-free metanephrines measured by EIA have better diagnostic test characteristics than urinary catecholamines in the diagnosis of pheochromocytoma. The EIA offers a simple and effective measurement of plasma-free metanephrines. [ABSTRACT FROM AUTHOR]