Protection against lethal murine coccidioidomycosis by a soluble vaccine from spherules

The formaldehyde-killed, whole-spherule vaccine, which is protective against lethal challenge of laboratory animals with Coccidioides immitis, was fractionated. It yielded a soluble, multicomponent, subcellular fraction termed the 27K vaccine. This vaccine, when it was accompanied by adjuvant, protected mice against lethal intranasal and intravenous challenge with C. immitis.     

The new age of liver transplantation

The advent of cyclosporin A for immunosuppression (IS) in liver transplantation (LTx) in the early 1980s heralded a new age for LTx, resulting in widespread application, rapidly expanding indications, relaxation of restrictions in donor selection and advances in the preservation of liver grafts and management of LTx operations. Liver transplantation, together with the transplantation of other organs (kidney, pancreas, heart, heart-lung, intestine), became possible. In Australia, around 125 LTx (22% in children) are performed each year. Indications are: primary sclerosing cholangitis; primary biliary cirrhosis; auto-immune hepatitis; chronic viral hepatitis; biliary atresia; metabolic disorders; fulminant hepatic failure (FHF); alcoholic cirrhosis; and malignancy (cancer, CA). Since 1965, 810 patients underwent LTx and 70 (9%) re-Tx. Patient survivals at 1, 5 and 9 years post-Tx are 80, 74 and 66%, respectively. Patients with primary diseases that recur in the LTx (hepatitis B and CA) do less well following LTx, with 5-year survival rates of 55 and 40%, respectively). Recent developments include: increasing the availability of donor organs by the use of living donors, 'split' cadaveric donor (CD) grafts, 'marginal' and non-heart-beating CD grafts and xenografts; expanding the indications for LTx; development of effective liver support systems for patients with FHF; the treatment of diabetics with liver failure with islet Tx (at the time of LTx); more effective immunosuppression; and methods to diminish recurrent disease in LTx. Some understanding of the unique 'tolerogenic' capabilities of the liver has come with the recognition of 'two-way microchimerism'. The satisfactory 5-9 year outcomes for patients underline the cost-effectiveness of LTx.     

Aggregation and motor neuron toxicity of an ALS-linked SOD1 mutant independent from wild-type SOD1

Analysis of transgenic mice expressing familial amyotrophic lateral sclerosis (ALS)-linked mutations in the enzyme superoxide dismutase (SOD1) have shown that motor neuron death arises from a mutant-mediated toxic property or properties. In testing the disease mechanism, both elimination and elevation of wild-type SOD1 were found to have no effect on mutant-mediated disease, which demonstrates that the use of SOD mimetics is unlikely to be an effective therapy and raises the question of whether toxicity arises from superoxide-mediated oxidative stress. Aggregates containing SOD1 were common to disease caused by different mutants, implying that coaggregation of an unidentified essential component or components or aberrant catalysis by misfolded mutants underlies a portion of mutant-mediated toxicity.     

The ability of non-invasive physiological tests to detect arterial occlusions in the lower extremity. An ROC study with particular regard to recruitment of patients for clinical trials

In the prerandomization phase of a clinical trial it is essential to be able to exclude, in a non-invasive way, patients who cannot be randomized into the trial. The ability of routine non-invasive physiological examinations to detect arterial occlusion in the lower extremities was investigated in 182 patients with hypercholesterolaemia. Ankle blood pressure measurement, pulse oscillometry, digital pulse plethysmography and treadmill and cycle exercise tests were performed as part of the prerandomization phase of the Probucol Quantitative Regression Swedish Trial (PQRST). The PQRST was designed to compare the antiatherosclerotic effect of two different lipid-lowering regimens. Before randomization the patients also underwent aorto-femoral arteriography, which was used as 'gold standard'. The results were analysed with ROC methodology. Ankle blood pressure measurement (ABP) and inclination time (IT), measured with digital pulse plethysmography, without significant mutual difference, were the variables, best able to detect occlusions. For ABP, the AZ-values were 0.85, 0.82 and 0.94 in detection of right-sided, left-sided and bilateral occlusion, respectively. The corresponding figures for IT were AZ = 0.86, 0.91 and 0.93. If a bilateral occlusion was predicted in a patient with an ABP value of < = or 0.98, a specificity of 0.90 and a sensitivity of 0.87 were obtained, using arteriography as reference method. For IT, with a critical value of 320 ms, sensitivity and specificity were 0.83 and 0.90, respectively.     

Capnography: assessing end-tidal CO2 levels

The purpose of this article is to describe the nurse's role in caring for patients with capnography. Capnography provides a continuous and non-invasive measure of arterial partial pressure of carbon dioxide (PaCO2) throughout the entire respiratory cycle. Used correctly, this technology assists the critical care nurse in providing adequate oxygenation and ventilation to the unstable patient.     

Apomorphine-induced yawning in the rat: influence of fasting and time of day

Yawning behavior is an experimental tool to study physiological responses, to elucidate the mechanisms of action of some drugs and hormones, and it is also a paradigm for some diseases and for dopamine (DA) agonists' clinical use. In this study, the effects of 24- and 48-h fasting as well as the influence of the light-dark cycle on apomorphine (APO)-induced yawning were evaluated. Initially, control and 48-h-fasted adult male rats were tested for yawning induced by APO (50, 100, 150 micrograms/kg, SC). The most effective dose tested was 100 micrograms/kg. Fasting significantly lowered yawning in all doses tested. Comparison between 24- and 48-h-fasted rats for APO (100 micrograms/kg)-induced yawning showed no significant difference between groups. Ad lib-fed groups were tested for APO (100 micrograms/kg)-induced yawning in both the light and in the dark phases of the cycle. Total number of yawnings increased significantly in the dark period. The present data show that fasting reduces and dark period increases APO-induced yawning in rats, suggesting that these conditions modulate the expression of this behavior.     

A cytoplasmic acyl-protein thioesterase that removes palmitate from G protein alpha subunits and p21(RAS)

Thioacylation is one of a handful of reversible covalent protein modifications, but the enzymes responsible for addition and removal of long chain fatty acids from protein cysteine residues in vivo have not yet been identified. The alpha subunits of some heterotrimeric G proteins cycle between thioacylated and deacylated states in a receptor-regulated fashion. We have identified, purified, and characterized an enzyme acyl-protein thioesterase that deacylates Galpha proteins and at least some other thioacyl protein substrates, including Ha-RAS. The action of this enzyme on thioacylated heterotrimeric Gs is regulated by activation of the G protein. Although native and recombinant acyl-protein thioesterases act as both acyl-protein thioesterases and lysophospholipases in vitro, we demonstrate by transfection that the enzyme can accelerate the turnover of thioacyl groups on Gsalpha in vivo.     

Replicable unconscious semantic priming

In 4 experiments, subjects classified visually presented target words as pleasant-unpleasant words or male-female first names. Prime words were similar (congruent) or dissimilar (incongruent) in meaning to targets. Brief duration of prime words (17, 33, or 50 ms), along with pre- and postmasking, prevented most subjects from perceiving their physical and semantic properties. By constraining response latencies to fall within a response window--a narrow time band that occurred earlier than subjects would ordinarily respond--these experiments consistently produced subliminal priming effects, indicated by greater error rates for incongruent than congruent priming trials. This conclusion was confirmed by analyzing magnitude of priming as a regression function of prime perceptibility using the method of A. G. Greenwald, M. R. Klinger, and E. S. Schuh (1995). The data of each experiment passed their significant-intercept criterion for demonstrating unconscious cognition.