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Several UpRXR cDNA variants were found in regions that could potentially influence function. A 5 aa insertion/deletion is located in the 'T' box in the D domain. Another 33 aa insertion/deletion is found inside the ligand binding domain, between helix 1 and helix 3. Expression vectors for these UpRXR variants and UpEcR were constructed, and proteins expressed in E. coli and in vitro TNT expression systems. The expressed crab nuclear receptors were then characterized by EMSA and GST-pull down experiments. The pull-down results show UpEcR interactions with those UpRXR variants that have the 33 aa insertion, but not with those lacking the 33 aa insertion. Although weak UpRXR protein-protein binding is observed, only pairing between -33 and +33 UpRXR LBD domains results in a pull-down. EMSA results show that UpEcR/UpRXR heterocomplexes bind with a IRper1 hormone responsive element only if UpRXR contains the 33 aa insertion. UpRXR lacking both the 5 aa and 33 aa insertion however, is found to bind a DR-1 HRE as a homocomplex. These in vitro protein-protein and protein-DNA interactions are hormone (20-hydroxy-ecdysone and 9-cis-retinoid acid) independent. Temporal and spatial distribution of UpEcR and UpRXR were studied by immunohistochemical analysis: Polyclonal antibodies against E. coli expressed NB domain and common domain proteins of UpEcR and UpRXR were applied to limb sections throughout the regeneration cycle. A large group of tissues and cell populations are immuno-reactive to UpEcR and UpRXR antibodies. The immuno-reactive patterns suggest that UpEcR and UpRXR are often co-localized.

Arthropods have a non-living exoskeleton that is composed of a lipoprotein epicuticle, underlying exocuticle and deeper thick endocuticle. The deepest component, the membranous layer, is an uncalcified zone immediately above a sheet of epithelial cells called the hypodermis. Molting, or ecdysis, is achieved when the animal manufactures a new exoskeleton, separates from and then crawls out of the old exoskeleton. Under the influence of a group of invertebrate steroids named ecdysteroids, hypodermal cells secrete a hydrolytic molting fluid that begins digesting the membranous layer. As hydrolysis completes, the endocuticle separates from the hypodermis by a process termed apolysis. We report here preliminary results investigating the role of ecdysteroids in regulation of apolysis. Hemolymph ecdysteroid titers from fiddler crabs forced to molt by multiple autotomy (reflexive loss of limbs) were quantified by radioimmunoassay. Two distinct titer trends have emerged. Certain crabs follow the short cycle. A rise in hemolymph ecdysteroid levels occurs at R3 (relative growth indicator determined by dividing the limb bud length by the carapace width) of about 16, limb buds continue to grow and the group molts within 3-5 weeks after autotomy. This premolt hormone peak evidently initiates apolysis. Some animals did not progress through the molt cycle with their cohorts. Their ecdysteroid titers remained low, limb buds did not grow and hormone levels did not peak during premolt. These crabs, following a long cycle, did not molt with their cohorts. Instead, all specimens not sacrificed died without molting. It appears that this premolt peak of ecdysteroids is necessary for completion of the molt cycle. We are currently completing studies that will correlate the hormone titers from experimental crabs with the completion of apolysis.

Summarizes work on the histological, physiological and molecular aspects of limb regeneration in the fiddler crab Uca pugilator. Hard exoskeleton as constraint to growth in most crustaceans; Basal and proecysial growth as two phases of limb regeneration in fiddler crab Uca pugilator; Occurence of fibroblast growth factors (FGF)-like immuno-reactivity during wound healing in Uca pugilator.

The article focuses on the Anaesthetic management of a known or suspected malignant hyperthermia susceptible patient. Topics discussed include identify patients who are at increased risk of developing malignant hyperthermia (MH); describe the preoperative preparations required before anaesthetising a patient susceptible to MH; and develop a plan for safe anaesthesia for specific operations in patients susceptible to MH.

• Decision making surrounding multiorgan transplantation is complex and controversial. • Heart-lung-liver transplant recipients have been young, cirrhotic patients with cystic fibrosis with severe lung disease. • Despite preservation of synthetic function, portal hypertension is universal. • Prolonged waitlist times should be anticipated when considering transplant listing. Combined multivisceral transplantation has emerged as a therapeutic option for a select patient cohort; however, clinical decision-making remains complex and controversial. The aim of this study was to examine patient characteristics, operative complications, and long-term outcomes of all patients who have undergone combined heart-lung-liver transplantation (HLLTx) in Australia. In this study, we performed a retrospective analysis of all adult patients who have undergone combined HLLTx in Australia to date. Recipient clinical characteristics, waitlist, and transplant outcomes are described. Eight adult patients have received HLLTx at a single Australian transplant center. Recipients of HLLTx have typically been young (median age, 30.1 years; range, 24-37), underweight (median body mass index, 19.8 kg/m2; range, 16.2-30.4) patients with cystic fibrosis (n = 8, 100%) with severe airflow obstruction (median forced expiratory volume in the first second of expiration, 24% predicted; range, 17%-48%) accompanied by liver cirrhosis confirmed on histopathology (n = 8, 100%). Despite relative preservation of synthetic function and low model for end-stage liver disease scores (median, 8; range, 6-17), all recipients had complications of portal hypertension prior to transplantation, with many patients having suffered life-threatening variceal hemorrhage. In this cohort, HLLTx was associated with overall posttransplant survival of 87.5% at 30 days, 71.4% at 1 year, and 42.9% at 5 years. Listing for combined HLLTx was associated with prolonged waitlist times relative to bilateral sequential single-lung transplantation (median 556 vs 56 days, respectively), however waitlist mortality and/or delisting was comparable between groups. Taken together, these findings highlight the opportunities and challenges facing combined (heart-) lung and liver transplantation in patients with multiorgan failure. [ABSTRACT FROM AUTHOR]