Modulating TRADD to restore cellular homeostasis and inhibit apoptosis.

Cell death in human diseases is often a consequence of disrupted cellular homeostasis. If cell death is prevented without restoring cellular homeostasis, it may lead to a persistent dysfunctional and pathological state. Although mechanisms of cell death have been thoroughly investigated, it remains unclear how homeostasis can be restored after inhibition of cell death.

ABIN-1 heterozygosity sensitizes to innate immune response in both RIPK1-dependent and RIPK1-independent manner.

ABIN-1 (encoded by the gene Tnip1) is a ubiquitin-binding protein that can interact with ubiquitin-editing enzyme A20 (encoded by the gene TNFAIP3) to restrain the activation of necroptosis and NF-κB activation. Genetic variants in the genes Tnip1 and TNFAIP3 are both strongly associated with susceptibility to autoimmune chronic inflammatory diseases such as psoriasis vulgaris and systemic lupus erythematosus (SLE) in humans. Here we investigated the mechanism by which ABIN-1 regulated innate immune responses.

Regulation of a distinct activated RIPK1 intermediate bridging complex I and complex II in TNFα-mediated apoptosis.

Stimulation of cells with TNFα can promote distinct cell death pathways, including RIPK1-independent apoptosis, necroptosis, and RIPK1-dependent apoptosis (RDA)-the latter of which we still know little about. Here we show that RDA involves the rapid formation of a distinct detergent-insoluble, highly ubiquitinated, and activated RIPK1 pool, termed "iuRIPK1." iuRIPK1 forms after RIPK1 activation in TNF-receptor-associated complex I, and before cytosolic complex II formation and caspase activation.

ABIN-1 regulates RIPK1 activation by linking Met1 ubiquitylation with Lys63 deubiquitylation in TNF-RSC.

Ubiquitylation of the TNFR1 signalling complex (TNF-RSC) controls the activation of RIPK1, a kinase critically involved in mediating multiple TNFα-activated deleterious events. However, the molecular mechanism that coordinates different types of ubiquitylation modification to regulate the activation of RIPK1 kinase remains unclear. Here, we show that ABIN-1/NAF-1, a ubiquitin-binding protein, is recruited rapidly into TNF-RSC in a manner dependent on the Met1-ubiquitylating complex LUBAC to regulate the recruitment of A20 to control Lys63 deubiquitylation of RIPK1.

Autophagy proteins play cytoprotective and cytocidal roles in leucine starvation-induced cell death in Saccharomyces cerevisiae.

Autophagy is essential for prolonging yeast survival during nutrient deprivation; however, this report shows that some autophagy proteins may also be accelerating population death in those conditions. While leucine starvation caused YCA1-mediated apoptosis characterized by increased annexin V staining, nitrogen deprivation triggered necrotic death characterized by increased propidium iodide uptake. Although a Δatg8 strain died faster than its parental strain during nitrogen starvation, this mutant died slower than its parent during leucine starvation.

Identification of autophagy genes participating in zinc-induced necrotic cell death in Saccharomyces cerevisiae.

Eukaryotes use a common set of genes to perform two mechanistically similar autophagic processes. Bulk autophagy harvests proteins nonselectively and reuses their constitutents when nutrients are scarce. In contrast, different forms of selective autophagy target protein aggregates or damaged organelles that threaten to interfere with growth.

Direct interactions of intraflagellar transport complex B proteins IFT88, IFT52, and IFT46.

Intraflagellar transport (IFT) particles of Chlamydomonas reinhardtii contain two distinct protein complexes, A and B, composed of at least 6 and 15 protein subunits, respectively. As isolated from C. reinhardtii flagella, IFT complex B can be further reduced to a approximately 500-kDa core that contains IFT88, 2x IFT81, 2x IFT74/72, IFT52, IFT46, IFT27, IFT25, and IFT22.

New 3-hydroxyflavanone (dihydroflavonol) phytoalexins from the papilionate legume Shuteria vestita.

Diffusates from the fungus-inoculated leaflets of Shuteria vestita have yielded four novel 3-hydroxyflavanone (dihydroflavonol) phytoalexins. From spectroscopic and chemical evidence, three of these phytoalexins have been identified as (2R,3R,2''R)--3,5,4'-trihydroxy-2'-isopropenyldihydrofurano (4'',5''; 6,7) flavanone (shuterol,1), (2R,3R)--3,5,7,4'-tetrahydroxy-6-(3,3-dimethylally) flavanone (shuterin, 2), and (2R,3R,2''R)--3,5,2',4'-tetrahydroxy-2''-isopropenyldihydrofurano (4'',5''; 6,7)flavanone (shuterone A, 3). The fourth compound (shuterone B, 4) is considered to be the 2S,3R stereoisomer of shuterone A.

Alcohol and hypertension: implications from research for clinical practice.

Despite the fact that recent epidemiological and laboratory studies appear to confirm that alcohol has an effect upon blood pressure, its impact has largely been ignored in clinical practice. This study was undertaken in an effort to answer four basic questions Is there an association between blood pressure and ethanol ingestion and if so is it causal or related to common genetic and/or environmental factors?; If an association exists, what is its likely physiological mechanism?; What additional studies are needed in order to further elucidate the relationship between alcohol and blood pressure?; What clinical recommendations, if any, are justified with our present state of knowledge?

Analysis of soybean sapogenins by high-performance liquid chromatography.

A method for the analysis of soybean sapogenins is described. The method is based on the extraction of soybean saponins from a defatted sample. The triterpene glycosides are then hydrolysed with subsequent analysis of the liberated sapogenins by high-performance liquid chromatography using gradient elution and mass detection.

Plasma epinephrine concentration in healthy men: correlation with systolic pressure and rate-pressure product.

Relations among plasma epinephrine, norepinephrine and renin activity and systolic pressure, diastolic pressure, heart rate and the product of heart rate and systolic pressure (rate-pressure product) were evaluated in 31 healthy men whose arterial pressure spanned the range from normal to mildly elevated. Measurements were made during 60 minutes with the patient in the supine position and during 10 minutes of quiet standing. In the supine position, highly significant regressions were found between systolic pressure or rate-pressure product and plasma epinephrine, but not between these variables and norepinephrine or renin activity.

Effect of guanabenz on blood pressure responses to posture and exercise.

A single dose of guanabenz was examined for effects upon blood pressure, heart rate, plasma catecholamines, and plasma renin activity in a randomized, double-blind, crossover design. Eight patients were studied when supine, standing, and during submaximal exercise. Guanabenz reduced blood pressure in subjects who were supine or standing.

Addition of acebutolol to diuretics in hypertension.

The effect of acebutolol as an antihypertensive beta receptor-blocking drug was evaluated in 15 patients that remained hypertensive while on diuretics. Observations were made in a small randomized double-blind trial in which the drug was compared to placebo and subsequently during a single-blind phase when the drug was given to those who had not responded to placebo. The dose range for acebutolol was 200 to 600 mg twice daily.

Plasma catecholamines in hypertension and pheochromocytoma determined using ion-pair reversed-phase chromatography with amperometric detection: investigation of the separation mechanism and clinical methodology.

The retention behavior of catecholamines (CAs) in ion-pair reversed-phase chromatography is examined. From the effects of pH, ionic strength and a secondary ion-pairing reagent (citric acid), under our chromatographic conditions, the retention behavior can be explained by assuming a mixed ion-exchange mechanism with octyl sulfate and citrate, on the column and in the mobile phase, respectively. The developed separation method was applied to the analysis of CAs in plasma samples purified by alumina adsorption and detected amperometrically.

Quantitative determination of 3-methoxy-4-hydroxyphenylethyleneglycol and its sulfate conjugate in human lumbar cerebrospinal fluid using liquid chromatography with amperometric detection.

A sensitive and direct reversed-phase liquid chromatographic method with amperometric detection was developed for the determination of 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG). The concentrations of the free and sulfate conjugate of MHPG were measured in human lumbar cerebrospinal fluid. All samples were preconcentrated by extraction with ethyl acetate.

Structural functions of the sweet pharmacophore.

The relative sweetness, onset times, and durations of response of D-glucose, D-xylose, D-quinovose, D-galactose, L-arabinose, and D-fucose were determined at four temperatures. The results can be interpreted by simple concepts of intramolecular hydrogen bonding which indicate that the so-called gamma-function of the tripartite AH,B, gamma sweet pharmacophore plays little or no part in sugar sweetness. Probably the Lemieux effect (intramolecular hydrogen bonding between the hydroxymethyl substituent and the 4-hydroxy group) is of overriding importance in determining sugar sweetness, and the separate features of intensity and time of response indicate distinct functions of chemoreception.

Analysis of urinary metanephrines by reversed-phase high-performance liquid chromatography and electrochemical detection.

A sensitive and specific direct analysis of urinary normetanephrine (NMN) and metanephrine (MN) was achieved utilizing reversed-phase high performance liquid chromatography and electrochemical detection. Individual specimens from "control" subjects and those with pheochromocytoma were hydrolyzed and the metanephrines separated from other urinary constituents by elution with ammonia from a Dowex CG-50 resin. Chromatographic peaks were identified by retention behavior, co-chromatography with reference compounds, ratio of responses at various oxidation potentials and stopped-flow UV spectra of the collected fractions.

Metabolism of D, L-3H-norepinephrine in essential hypertension.

Defective control of the cardiovascular system by the sympathetic nerves continues to be incriminated as the potential primary physiologic defect in essential hypertension (EH). The need to measure sympathetic tone has progressed from physiologic mensuration by assessment of reflex and pharmacological responses to the recent assay of norepinephrine (NE) and its congeners in both urine and plasma. The way in which the body handles D,L-B-3H-NE represents yet another technique by which to evaluate sympathetic function.

Urinary tritium excretion following intravenous 3H-norepinephrine administration in hypertensive rats.

Spontaneously hypertensive rats (SHR), salt-resistant (SRR), salt-sensitive (SSR), and Sprague-Dawley DOC-salt nephrectomized rats were tested by evaluation of tritiated norepinephrine uptake and blood pressure with diets containing various amounts of sodium. Only Sprague-Dawley rats who had been both nephrectomized and given DOC on a high salt diet (8%) illustrated the elevated tritium excretion similar to that observed in human subjects with essential hypertension.