Circulating-water garment or the combination of a circulating-water mattress and forced-air cover to maintain core temperature during major upper-abdominal surgery.

BACKGROUND: A recent heat-balance study in volunteers suggested that greater efficacy of circulating-water garments (CWGs) results largely from increased heat transfer across the posterior skin surface since heat transfer across the anterior skin surface was similar with circulating-water and forced-air. We thus tested the hypothesis that the combination of a circulating-water mattress (CWM) and forced-air warming prevents core temperature reduction during major abdominal surgery no worse than a CWG does. METHODS: Fifty adult patients aged between 18 and 85 yr old, undergoing major abdominal surgery, were randomly assigned to intraoperative warming with a combination of forced-air and a CWM or with a CWG (Allon ThermoWrap). Core temperature was measured in the distal oesophagus. Non-inferiority of the CWM to the CWG on change from baseline to median intraoperative temperature was assessed using a one-tailed Student's t-test with an equivalency buffer of -0.5°C. RESULTS: Data analysis was restricted to 16 CWG and 20 CWM patients who completed the protocol. Core temperature increased in both groups during the initial hours of surgery. We had sufficient evidence (P=0.001), to conclude that the combination of a CWM and forced-air warming was non-inferior to a CWG in preventing temperature reduction, with mean (95% CI) difference in the temperature change between the CWM and the CWG groups (CWM-CWG) of 0.46°C (-0.09°C, 1.00°C). CONCLUSIONS: The combination of a CWM and forced-air warming is significantly non-inferior in maintaining intraoperative core temperature than a CWG. TRIAL REGISTRY: This trial has been registered at clinical trials.gov, identifier: NCT 00651898.

Outcomes of transoral laser microsurgery for recurrent head and neck cancer.

OBJECTIVE: To report our outcomes with salvage CO2 laser surgery following recurrence of laryngeal and oropharyngeal cancer after radiotherapy. METHOD: This study entailed a prospective review of patients treated with transoral laser microsurgery for recurrent laryngeal and oropharyngeal cancer between 2002 and 2010 at the Queen Elizabeth II Health Science Centre in Canada. RESULTS: Sixteen patients were identified, with a mean follow up of 30.6 months. Five patients died of recurrence. Complications were common in patients with oropharyngeal cancer. The overall survival and disease-free survival rates at an average of 29.8 months follow up were 50 per cent and 68.8 per cent respectively. CONCLUSION: Salvage surgery using transoral laser microsurgery should be considered in the management of patients with recurrent laryngeal and oropharyngeal cancer. This technique offers acceptable salvage rates with less comorbidity than other treatments.

Transplantation of porous tubes following spinal cord transection improves hindlimb function in the rat.

STUDY DESIGN: Experimental. OBJECTIVE: To determine the effects of a porous tube transplant in spinal cord transected rats. SETTING: Acadia University, Wolfville, Nova Scotia, Canada. METHODS: Female rats were randomly assigned to three experimental groups: control (Con, n=8), spinal cord transected (Tx, n=5) and spinal cord transected with transplant (TxTp, n=7). The rats in the TxTp and Tx groups received a complete spinal cord transection at the T10 level and the TxTp group immediately received a porous tube transplant. RESULTS: Locomotor activity rated on the Basso, Beattie, Bresnahan scale improved significantly in the TxTp animals over the 4 weeks such that final scores were 21, 1.4 and 7.1 for the Con, Tx and TxTp groups, respectively. As expected, the muscle to body mass ratios of the hindlimb skeletal muscles of the Tx group were decreased (soleus 35%, plantaris 29% and gastrocnemius 29%) and this was also observed in the TxTp group (soleus 33%, plantaris 23% and gastrocnemius 30%). Cytochrome c oxidase (CYTOX) activity in the plantaris was decreased by Tx but maintained in the TxTp group (Con=82.2, Tx=44.8 and TxTp=72.8 U/min/g). CONCLUSION: Four weeks after the spinal cord transection, plantaris CYTOX activity and locomotor function improved with porous tube implantation. SPONSORSHIP: Natural Sciences and Engineering Research Council.

RET mutations in multiple endocrine neoplasia type 2 and Hirschsprung disease.

Mutations in the RET proto-oncogene have been found in a large proportion of families affected by the multiple endocrine neoplasia type 2 syndrome and in familial and sporadic Hirschsprung disease. This review discusses the role of the RET receptor tyrosine kinase in the etiology of these dominantly inherited disorders of neural crest development. In addition, the role of genetic screening is considered in the identification and clinical management of individuals at risk for these diseases.

The Rho-family GTP exchange factor Vav is a critical transducer of T cell receptor signals to the calcium, ERK, and NF-kappaB pathways.

Vav is a GTP/GDP exchange factor (GEF) for members of the Rho-family of GTPases that is rapidly tyrosine-phosphorylated after engagement of the T cell receptor (TCR), suggesting that it may transduce signals from the receptor. T cells from mice made Vav-deficient by gene targeting (Vav-/-) fail to proliferate in response to TCR stimulation because they fail to secrete IL-2. We now show that this is due at least in part to the failure to initiate IL-2 gene transcription. Furthermore, we analyze TCR-proximal signaling pathways in Vav-/- T cells and show that despite normal activation of the Lck and ZAP-70 tyrosine kinases, the mutant cells have specific defects in TCR-induced intracellular calcium fluxes, in the activation of extracellular signal-regulated mitogen-activated protein kinases and in the activation of the NF-kappaB transcription factor. Finally, we show that the greatly reduced TCR-induced calcium flux of Vav-deficient T cells is an important cause of their proliferative defect, because restoration of the calcium flux with a calcium ionophore reverses the phenotype.