Donor-site local anaesthetic infusion catheter as an opioid-sparing agent in free flap reconstruction of the head and neck: a valuable adjunct to an enhanced recovery protocol.

This paper presents the results of a retrospective case-controlled cohort study to investigate the effectiveness of a donor-site local anaesthetic infusion protocol to reduce opioid requirements, length of intensive therapy unit (ITU) stay, and incidence of postoperative delirium. Adult free flap head and neck patients were identified from a prospective database (n = 86). There was a significant reduction in mean opioid requirements (p < 0.001). Postoperative delirium was observed in 12 of 35 patients before introduction of the protocol, and in 10 of 51 patients after its introduction (p = 0.139). Donor-site local anaesthetic infusion reduces opioid requirements for patients undergoing head and neck free flap reconstruction, and is a valuable adjunct to an enhanced recovery protocol.

'Out of house' virtual surgical planning for mandible reconstruction after cancer resection: is it oncologically safe?

The purpose of this study was to investigate whether the time delay between 'out of house' proprietary virtual surgical planning (OH-VSP) of the mandibular resection for oral cancer and the actual surgery results in compromised margins and oncological disadvantage for the patient. Outcomes of patients who had OH-VSP of their mandibular resection and reconstruction were compared with those of patients who had the same surgery using a conventional non-VSP approach. The groups were similar in patient demographics, tumour stage and size, nodal status, and reconstruction complexity. VSP resulted in a significant reduction in operating time (P<0.01). VSP did not affect bony (P=0.49) or soft tissue (P=0.22) margin status. In summary, VSP reduced the operating theatre time, and despite the time interval between bony resection planning and surgery, there was no compromise to the oncological safety of the operation.

Results of flap reconstruction: categorisation to reflect outcomes and process in the management of head and neck defects.

The reporting of the outcomes of flap reconstruction is often based on numerical success rates. Whilst this remains a useful variable with which to measure success, it is limited in its ability to reflect the complex processes involved. The lack of consistency in the categorisation of outcomes of flap reconstruction in the head and neck could potentially lead us to lose the opportunity to fully capture the implications of its success or failure, or both. We propose a classification that moves away from primarily reporting the results of its binary nature, and focuses more on the process of reconstruction, particularly in the head and neck.

Adenosine-mediated killing of cultured epithelial cancer cells.

Because micromolar concentrations of adenosine (Ado) have been documented recently in the interstitial fluid of carcinomas growing in animals, we examined the effects of low concentrations of Ado on the growth of cultured human carcinoma cells. Ado alone had little effect upon cell growth. In the presence of one of a number of Ado deaminase (ADA) inhibitors, Ado led to significant growth inhibition of all cell lines tested. Similar effects were found when ATP, ADP, or AMP was substituted for Ado. Surprisingly, the ADA inhibitor coformycin (CF) had a much greater potentiating effect than did 2'-deoxycoformycin (DCF), although DCF is a more potent ADA inhibitor. The growth inhibition of the Ado/CF combination was not abrogated by pyrimidines or caffeine, a nonspecific Ado receptor blocker. Toxicity was prevented by the addition of the Ado transport inhibitor dipyridamole or the Ado kinase inhibitor 5'-amino 5'-deoxyadenosine. S-Adenosylhomocysteine hydrolase is not involved because neither homocysteine thiolactone nor an S-adenosylhomocysteine hydrolase inhibitor (adenosine dialdehyde) potentiated toxicity of the Ado/CF combination. Unexpectedly, substitution of 2'-deoxyadenosine (the toxic moiety in congenital ADA deficiency) for Ado, did not lead to equivalent toxicity. The Ado/CF combination inhibited DNA synthesis and brought about morphological changes consistent with apoptosis. Together, these findings indicate that the Ado-mediated killing proceeds via an intracellular route that requires the action of Ado kinase. The enhanced cofactor activity of CF may be attributable to its being a more potent inhibitor of AMP deaminase than is DCF.

Assessment of coagulation system activation using spot urine measurements.

Coagulation system activation is most commonly assessed by measuring levels of one or more proteins in peripheral blood. Because faulty blood-drawing can cause activation of the coagulation system, artifactual elevations of such markers have been reported. We have therefore investigated the possibility of using randomly collected ('spot') urine samples as a non-invasive means of assessing the state of coagulation system activation. Using a commercially available enzyme-linked immunosorbent assay kit designed to measure plasma levels of fragment 1 + 2, we found immunoreactive fragment 2 in healthy control subjects, and significantly increased levels in diabetic and non-diabetic pregnant subjects, and patients with venous thromboembolism, prostate cancer, and diabetes. Measurements of excretion of immunoreactive fragment 2 are worth further study as an adjunct or alternative to plasma-based assays designed to detect or quantify coagulation system activation.

Cellular communication through signal transduction: the background.

Chemical signals are the language of information exchange among the cells of the body. These signals, which bind to receptors to relay information into the cell, include hormones, neurotransmitters, growth factors, and cytokines. The relay of information is referred to as signal transduction. Information that is transduced into the cell may elicit short term responses such as contraction, secretion, or a change in metabolic processes. Alternatively, the signals may direct long-term responses involving differential gene expression and cell growth. Signal-mediated information exchange is essential for cellular homeostasis and coordination of all body functions. Defects in cellular communication and signal transduction are the molecular basis of cardiovascular dysfunction and pathology. Present and future therapeutic medical and nursing interventions will be based on this emerging paradigm. This article describes how chemical signals transduce or transfer information from the outside to the inside of the cell. This information provides theoretical background for the other articles in this and the next issue of The Journal of Cardiovascular Nursing, which will discuss the role of cell signaling in specific pathologic conditions or interventions.

Reverse phase liquid chromatographic determination of sulfathiazole residues in honey.

Sulfathiazole residues were extracted from honey by homogenizing samples in acetone, filtering, and then evaporating the acetone under nitrogen at 40 degrees C. The remaining extract was transferred to a separatory funnel with 1N HCl and ethyl ether. An aliquot of the retained acid layer was screened by using the Bratton-Marshall reaction. If the test was positive, the remaining portion was analyzed directly through a mu Bondapak phenyl column monitored by a UV detector at 254 nm. The mobile phase was potassium phosphate monobasic in 10% acetonitrile adjusted to pH 3.0. Time for elution was 13 min. Average recoveries were 78% at the 0.1 ppm spiking level and 68% at the 1.0 ppm level. The minimum detectable amount was 0.06 ppm based on a spiked sample extract.

Molecular characterization of a multi-promoter gene encoding a chicken filamin protein.

We report the cloning and sequencing of cDNA encoding a chicken filamin protein. The 2,567 amino acid protein contains an NH2-terminal 267 amino acid actin-binding domain followed by a series of 24 repeating units that are each approximately 95 amino acids in length. The overall primary structure of filamin closely resembles that of human actin-binding protein (ABP). However, filamin lacks a 24-amino-acid insertion prior to repeat 16 that is contained within ABP. This region of human ABP is a site of calpain cleavage and is thought to confer flexibility on the molecule. Hence, it is possible that the properties of actin gels formed with either human ABP or filamin reflect the presence or absence of this insertion. Filamin is encoded within a multi-promoter transcription unit. A downstream filamin promoter (Fil1) resembles those of certain housekeeping genes and has a putative binding site for the transcription factor E2F. Thus, transcription from this promoter may be linked to the cell cycle. A second filamin promoter (Fil2) is located at least 8 kilobases upstream from the Fil1 promoter. This structural arrangement suggests that regulation of filamin gene expression is likely to be complex.