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The ubiquitin-proteasome system (UPS) is critical for cellular and organismal health. To uncover mechanisms regulating the UPS in normal and stress conditions, we systematically probed the genome of the eukaryotic model system Saccharomyces cerevisiae for modulators of the UPS master regulator Rpn4 under basal and stress conditions using the reverse genetic method ReporterSeq. The top UPS regulators were the thioredoxin reductase Trr1 and proteins of the large ribosomal subunit, both of which had no previously known role in UPS regulation. Unlike all known mechanisms for Rpn4 regulation which regulate Rpn4 levels, we found that Trr1 modulates the molecular activity of Rpn4 and does so in response to oxidative stress. Our work illuminates the genetic landscape through which cells regulate the UPS, and provides insight into how cells combat proteotoxicity.

Understanding cellular stress response pathways is challenging because of the complexity of regulatory mechanisms and response dynamics, which can vary with both time and the type of stress. We developed a reverse genetic method called ReporterSeq to comprehensively identify genes regulating a stress-induced transcription factor under multiple conditions in a time-resolved manner. ReporterSeq links RNA-encoded barcode levels to pathway-specific output under genetic perturbations, allowing pooled pathway activity measurements via DNA sequencing alone and without cell enrichment or single-cell isolation. We used ReporterSeq to identify regulators of the heat shock response (HSR), a conserved, poorly understood transcriptional program that protects cells from proteotoxicity and is misregulated in disease. Genome-wide HSR regulation in budding yeast was assessed across 15 stress conditions, uncovering novel stress-specific, time-specific, and constitutive regulators. ReporterSeq can assess the genetic regulators of any transcriptional pathway with the scale of pooled genetic screens and the precision of pathway-specific readouts.

Work and Brandman measure how the ubiquitin-proteasome system (UPS) adapts to different types of stressors. They find that the UPS can adapt almost perfectly to stress conditions, even those that stabilize misfolded proteins through aggregation rather than increasing UPS substrate load., Aging, disease, and environmental stressors are associated with failures in the ubiquitin-proteasome system (UPS), yet a quantitative understanding of how stressors affect the proteome and how the UPS responds is lacking. Here we assessed UPS performance and adaptability in yeast under stressors using quantitative measurements of misfolded substrate stability and stress-dependent UPS regulation by the transcription factor Rpn4. We found that impairing degradation rates (proteolytic stress) and generating misfolded proteins (folding stress) elicited distinct effects on the proteome and on UPS adaptation. Folding stressors stabilized proteins via aggregation rather than overburdening the proteasome, as occurred under proteolytic stress. Still, the UPS productively adapted to both stressors using separate mechanisms: proteolytic stressors caused Rpn4 stabilization while folding stressors increased RPN4 transcription. In some cases, adaptation completely prevented loss of UPS substrate degradation. Our work reveals the distinct effects of proteotoxic stressors and the versatility of cells in adapting the UPS.

Aging, disease, and environmental stressors are associated with failures in the ubiquitin-proteasome system (UPS), yet a quantitative understanding of how stressors affect the proteome and how the UPS responds is lacking. Here we assessed UPS performance and adaptability in yeast under stressors using quantitative measurements of misfolded substrate stability and stress-dependent UPS regulation by the transcription factor Rpn4. We found that impairing degradation rates (proteolytic stress) and generating misfolded proteins (folding stress) elicited distinct effects on the proteome and on UPS adaptation. Folding stressors stabilized proteins via aggregation rather than overburdening the proteasome, as occurred under proteolytic stress. Still, the UPS productively adapted to both stressors using separate mechanisms: proteolytic stressors caused Rpn4 stabilization while folding stressors increasedRPN4transcription. In some cases, adaptation completely prevented loss of UPS substrate degradation. Our work reveals the distinct effects of proteotoxic stressors and the versatility of cells in adapting the UPS.

Temporal variation in prices is an important factor that influences returns on investments and decisions made by policy makers. This study investigates the behaviour of two output prices potentially associated with growing improved poplars in Canada: hardwood pulp and ethanol. Time series techniques are used to assess the processes and volatility of hardwood pulp and ethanol price series. The findings indicate that price series for hardwood pulp and ethanol are best characterized by mean reverting processes around constant averages, indicating more predictability for poplar producers than would be the case for random walks. However, the results from the volatility analysis suggest substantial uncertainty for producers. The volatility of both markets is found be to be highly related to past volatilities, and therefore persistent. To the extent that future prices are more volatile, the importance of producers considering multiple product options for pulp plantations increases, as do complexities for policy makers to predict the impacts of policies to support biofuels.

The arteriovenous graft (AVG) is most often used in hemodialysis patients when an autogenous fistula is not feasible. The optimal location (forearm or upper arm) and configuration (loop or straight) of AVGs are not known. To evaluate relationships of AVG location and configuration with patency, we conducted a secondary analysis using data from a randomized, placebo-controlled trial of dipyridamole plus aspirin for newly placed AVG.Participants of the Dialysis Access Consortium (DAC) Graft Study with newly placed upper extremity prosthetic grafts involving the brachial artery were studied. Multivariable analyses adjusting for trial treatment group, center, gender, race, body mass index, diabetes, current treatment with chronic dialysis, and prior arteriovenous vascular access or central venous catheter were performed to compare outcomes of forearm (fAVG) and upper arm (uAVG) grafts, including loss of primary unassisted patency (LPUP) and cumulative primary graft failure (CGF). Subgroup analyses of graft configuration and outflow vein used were also conducted.A total of 508 of the 649 participants (78%) enrolled in the trial had an upper extremity brachial artery graft placed, 255 with fAVG and 253 with uAVG. Participants with fAVG were less often male (33% vs 43%; P = .03), African American (62% vs 78%; P .001), and receiving dialysis at the time of surgery (62% vs 80%; P .001). Participants with fAVG had a higher mean body mass index (33 vs 29; P .001). The LPUP (fAVG 70% vs uAVG 78%; P = .07) and CGF (33% vs 36%; P = .91) were similar between fAVG and uAVG at 1-year follow-up. In multivariable analysis, AVG location (uAVG vs fAVG) was not associated with LPUP (hazard ratio, 1.21; 95% confidence interval, 0.90-1.63; P = .20) or CGF (hazard ratio, 1.36; 95% confidence interval, 0.94-1.97; P = .10). LPUP did not differ significantly between fAVG and uAVG among subgroups based on AVG configuration (P = 1.00) or outflow vein used (P = .16).Patency was comparable between fAVG and uAVG despite the larger caliber veins often encountered in the upper arm in carefully selected patients. Our findings support the traditional view that, in order to preserve a maximal number of access sites, the forearm location should be considered first before resorting to an upper arm graft.

The document defines the terms most commonly encountered in the field of polymer blends and composites. The scope has been limited to mixtures in which the components differ in chemical composition or molar mass and in which the continuous phase is polymeric. Incidental thermodynamic descriptions are mainly limited to binary mixtures although, in principle, they could be generalized to multicomponent mixtures. The document is organized into three sections. The first defines terms basic to the description of polymer mixtures. The second defines terms commonly encountered in descriptions of phase domain behavior of polymer mixtures. The third defines terms commonly encountered in the descriptions of the morphologies of phase-separated polymer mixtures.

The document defines the terms most commonly encountered in the field of polymer blends and composites. The scope has been limited to mixtures in which the components differ in chemical composition or molar mass and in which the continuous phase is polymeric. Incidental thermodynamic descriptions are mainly limited to binary mixtures although, in principle, they could be generalized to multicomponent mixtures. The document is organized into three sections. The first defines terms basic to the description of polymer mixtures. The second defines terms commonly encountered in descriptions of phase domain behavior of polymer mixtures. The third defines terms commonly encountered in the descriptions of the morphologies of phase-separated polymer mixtures. Reproduced from: Pure Appl. Chem., Vol. 76, No. 11, pp. 1985–2007, 2004. © 2004 IUPAC 9168_Book.indb 887 4/16/10 1:35 PM 888 handbook of biochemistry and Molecular biology

Catheter-related blood stream infections pose a significant risk for patients living with vascular catheters. The cost to manage these infections is substantial. Although the etiology of these infections is multifactorial, tap water has been implicated as a significant causative factor. This retrospective review evaluates the effectiveness of a surgical dressing, the CD-1000, at protecting catheters and exit site wounds from fluid and debris when patients engage in high risk activities like showering.All patients who received the CD-1000 from a single national medical supplier from September 2006 through to March 2007 were contacted to participate in this retrospective review; 209 patients, representing 34 states and 175 unique physicians, participated in this study. Effectiveness of the dressing along with prior and current history of catheter events was queried.The CD-1000 was 95% effective at keeping the catheter and exit site dry while patients engaged in high risk activities like showering. Prior to using the CD-1000, the 209 patients reported a historical catheter infection rate of 1.83 per 1000 catheter days. While using the CD-1000 the 209 patients reported a catheter infection rate of 0.47 per 1000 catheter days.The CD-1000 catheter specific composite dressing adequately protects vascular catheters and exit sites when patients engage in high risk activities like showering. In this geographically diverse retrospective review, use of the CD-1000 was associated with a 75% reduction in catheter associated infections.

The effect of varying intracapillary oncotic pressure on the rate of transcapillary volume flux in microperfused descending vasa recta (DVR) was studied during furosemide diuresis in the Munich-Wistar rat. At the papillary base, plasma protein concentration and hydraulic pressure were 5.7 +/- 0.1 g/dl and 11.7 +/- 0.7 mmHg in nonperfused DVR, respectively, and 5.6 +/- 0.1 g/dl and 9.4 +/- 0.4 mmHg in nonperfused ascending vasa recta (AVR), respectively. These results demonstrate that the papillary microcirculation does not remove water from the interstitium during furosemide diuresis and defines Starling forces in the pericapillary interstitium. Osmolality and urea concentration were 380 +/- 11 mosmol/kgH2O and 56 +/- 5 mM in DVR plasma at the papillary base, respectively, and 386 +/- 10 mosmol/kgH2O and 62 +/- 5 mM in DVR plasma at the tip, respectively. These results demonstrate abolition of corticomedullary small solute gradients. DVR were perfused at a rate of 10 nl/min with a buffer solution containing small-solute concentrations that matched those of plasma in nonperfused DVR. The buffer solution also contained 2 x 10(6) mol wt fluorescein isothiocyanate-labeled dextran (FITC-Dx, 5 mg/ml) and either 0.1 or 5.0 g/dl albumin. Microperfused DVR were punctured a second time downstream of the perfusion site for sample collection or servo-nulling pressure measurement. The rate of transmembrane volume flux, determined from the change in FITC-Dx concentration from perfusate to collectate, was 0.99 +/- 0.29 nl.min-1.mm-1 when perfusate contained 0.1 g/dl albumin and 0.00 +/- 0.23 nl.min-1.mm-1 with 5.0 g/dl albumin (P less than 0.01). Intracapillary hydraulic pressures were 21.7 and 20.4 mmHg during microperfusion of DVR with 0.1 and 5.0 g/dl albumin, respectively. These results demonstrate that transcapillary driving forces of 20 mmHg (5 g/dl albumin) influence transcapillary water movement across the DVR endothelium. For an average capillary diameter of 12.9 microns, DVR hydraulic conductivity is calculated to be greater than 1.4 x 10(-6) cm.s-1.mmHg-1.

Pancreatic transplantation (PTx) with portal venous delivery of insulin and enteric drainage of the exocrine secretion is more physiologic than bladder-systemic (BS) drainage. With portal-enteric (PE) PTx, the diagnosis of acute rejection (AR) requires a percutaneous biopsy. The roux-en-y (RNY) venting jejunostomy in patients with PEPTx offers a novel approach to monitor rejection and prevent anastomatic leaks.From January 1996 to December 1998, we performed 17 simultaneous kidney/pancreas transplants (SKPTx). The initial 4 patients underwent BS drainage and the subsequent 13 patients underwent RNY venting jejunostomy with PE drainage. All patients were treated with quadruple therapy. There were 9 males, 14 patients were Caucasian with a mean age of 32 yr (range 30-54 yr), and a mean pre-transplantation duration of diabetes of 25 yr. Six patients underwent endoscopic donor duodenal biopsy through the jejunostomy to rule out clinically suspected AR. Gastrograffin was inserted into the jejunostomy to examine the integrity of anastamosis when indicated. In 9 out of 13 patients, the venting jejunostomy was taken down 9-12 months post-transplantation after allograft function was stable.Actual patient, kidney, and pancreas graft survival rates were 100, 100 and 94%, respectively, after a mean follow-up of 16 months. Renal allografts functioned immediately in 89% of patients. The mean length of hospital stay was 19 d. Four (23%) patients (2 with BS drainage and 2 with PE drainage) suffered an AR episode in the first month, and 4 (23%) patients had five AR from 3-36 months post-transplantation. Other complications were post-operative bleeding in 3 patients, wound infection in 2 patients and a proximal duodenal stump leak in 1 patient. In patients with clinical rejection, endoscopy through the venting jejunostomy showed inflamed, friable doudenal mucosa and doudenal biopsy findings were compatible with AR.These preliminary results suggest that RNY venting jejunostomy with PE drainage can be used safely to diagnose and monitor pancreas AR and to diagnose and prevent anastamotic leaks. This technique will be even more useful to visualize transplanted duodenal mucosa, collect pancreatic secretions (amylase) for analysis and perform endoscopic retrograde cholangiopancreatography if needed to obtain pancreatic biopsies.

Predictive maintenance has become a familiar concept in industrial fault detection regime. The ability to detect early warning signals in systems in the form of small changes in dynamic behavior is essential to anticipate failures. In general accurate system models are an essential part in residual based fault detection. However, in complex nonlinear systems, the development of accurate models can be very difficult, thus usually other approaches are often selected. As an alternative to the nonlinear analytical models, neural networks have shown significant potential in accurately representing nonlinear systems. In this paper we show how a system identified by a neural network, and a nonlinear observer can be used to detect changes in system dynamics. Different methods for observer design are discussed. The experimental section show the observer implemented on a thermo fluid system. Several faults are introduced, and the observer prediction is compared to actual data.

Recombinant human erythropoietin (rHuEpo) can be administered to continuous ambulatory peritoneal dialysis (CAPD) patients subcutaneously (SC), intravenously (IV), and intraperitoneally (IP). Subcutaneous rHuEpo is preferred in CAPD patients because of its ease of administration and favorable pharmacokinetics. The longer half-life of SC rHuEpo allows for one or two doses per week. Since SC rHuEpo can cause pain and local irritation at the injection site, the efficacy and safety of intramuscular (IM) rHuEpo were compared to SC rHuEpo in 6 random stable CAPD patients. The protocol in each subject consisted of a single weekly injection of IM rHuEpo for 3-6 months (period 1), crossover to SC rHuEpo for 3-6 months (period 2), and crossover to IM rHuEpo for 3-6 months (period 3). The rHuEpo dose was adjusted by protocol to achieve a target hematocrit of 30%-33%. Pain at the injection site was graded on a scale of 0-3. All patients preferred IM rHuEpo to SC rHuEpo because of less pain at the injection site. One patient tolerated IM rHuEpo for six months (period 1), then left the study after one month of SC rHuEpo because of ecchymoses and pain at the SC injection sites. In all patients, there was no significant difference in the dose of rHuEpo (U/kg/wk) during the three study periods.(ABSTRACT TRUNCATED AT 250 WORDS)

Hyperuricemia and gout have been associated with cyclosporine A (CyA) therapy in transplant recipients. We describe 4 patients who developed severe tophaceous gout after renal transplantation. All of the patients received CyA, prednisone, and diuretic therapy. Three had episodes of allograft rejection. No patient had the diagnosis of gout before transplantation. All developed tophi within 5 years of the first attack of gout. Management of these patients has been difficult due to renal insufficiency, drug interactions and toxicity. Clinicians should be aware that tophaceous gout can occur rapidly in CyA treated transplant recipients.

To study the association between renal renin release and the pentose pathway, we perfused nonfiltering kidneys from Sprague-Dawley rats with Krebs-Ringer bicarbonate buffer containing 5 mM glucose and 14 g/100 ml bovine serum albumin in the presence or in the absence of 0.25 mM 6-aminonicotinamide (6AN), an inhibitor of glucose-6-phosphate dehydrogenase, the rate-limiting step of the pentose pathway. Eleven kidneys perfused in the absence of 6AN had a renin secretion rate of 7.4 +/- 2.2 ng ANG I X min-1 X ml-1. In six kidneys perfused in the presence of 6AN, renin release was depressed to 0.56 +/- 0.24 ng ANG I X min-1 X ml-1. The renal renin content for four control kidneys was 56 +/- 3.3 ng ANG I X mg-1 X h-1 while in four kidneys perfused with 6AN renal renin content was lower, 35 +/- 2.9 ng ANG I X mg-1 X h-1. In the presence of 5 mM lactate, the renin release of eight nonfiltering kidneys was 0.31 +/- 0.06 ng ANG I X min-1 X ml-1. The addition of 6AN did not further depress renin secretion in the presence of lactate. 6-Aminonicotinamide also completely blocked furosemide-stimulated renin release without having any effect on glomerular filtration rate or furosemide-induced natriuresis. However, 6AN did not inhibit stimulation of renin secretion by isoproterenol. We conclude that 6-aminonicotinamide interferes with renin release by nonfiltering kidneys and also inhibits furosemide-stimulated renin release but does not affect beta-adrenergic-stimulated renin secretion. Glucose but not lactate is important for maintaining augmented rates of renin secretion in nonfiltering kidneys. 6-Aminonicotinamide significantly reduced renal renin content in the presence of glucose.(ABSTRACT TRUNCATED AT 250 WORDS)

SUMMARY The influenc of the renln-angiotensie n system on individual kidney function of two-kidney, oneclip Goldblatt hypertensive (GH wa) rats evaluates bdy determining renal functional responses during intra-venous infusio on f converting enzyme inhibitor (CEI) (SQ 20,881 0J rag/100, g-hr for) 3.5 bourn. Rats weremade hypertensiv be y placing a 0.25 mm silver clip on the right renal arter 3-y4 weeks prior to study. Normalrats and GH rats were prepare tdo allow urine collections from each kidney. Mean arteria of Gl pressurH erats fell significantly from preinfusio of 15n level3 ± 7s to 126 ± 4 mm Hg during CEI infusion. Despite thisdecrease in arterial pressure, the nondipped kidneys with reduced renal renin activit ± 5 vs 29y (13 ±4 40 ngAl/mg-hr in th clippee d kidney) exhibited dramati in gtomerulac increaser filtrations (GFR rat (fro)e m1.45 ± 0.06 to 2.56 ± 0.3 ml/mln)5 , urine (4.8 flow2 ± 0.71 to 9.11 ± 1.1 ^il/mln)9 , sodium excretion(0.10 ± 0.02 to 1.15 0.3 ± 9 MEq/mln), fractional sodium excretion (0.05 ± 0.02% % to 0.43 ±% 0.18%), andpotassium excretion (0.9 ±4 0.08 to 2.50 ± 0.55 /

Unidirectional fluxes of 42K+ and 86Rb+ were measured in isolated perfused segments of proximal straight tubules and no differences were found between the two isotopes for the same flux determination. In the three segments examined (the early and late superficial proximal straight tubule and the juxtamedullary proximal straight tubule) there was apparent net active K+ secretion as demonstrated by differences in the unidirectional fluxes of 2.6, 3.2, and 4.8 pmol.min-1.mm-1, respectively. However, in contrast to the expectations for active K+ secretion, the bath-to-lumen fluxes were unaffected by 0.1 mM ouabain added to the bathing solution, and in the early superficial and juxtamedullary segments these fluxes were directly proportional to the K+ concentration of the bathing solution over a range of concentrations. Apparent K+ permeability coefficients were calculated from lumen-to-bath fluxes to be 0.14 +/- 0.02, 0.10 +/- 0.02, and 0.52 +/- 0.07 micrometers.s-1 in the early and late superficial and juxtamedullary segments, respectively. Based on these data and on a mathematical analysis, we have concluded that active K+ secretion of the magnitude measured would have little importance in determining the K+ load delivered to the descending limb of the loop of Henle. However, the higher passive permeability of the juxtamedullary segment would allow significant net K+ secretion if the outer medullary interstitium had even a moderately elevated K+ concentration.

Acute variations in renal arterial pressure are associated with corresponding alterations in absolute and fractional sodium excretion even under conditions of highly efficient autoregulation of renal blood flow (RBF) and glomerular filtration rate (GFR). Since prostaglandins recently have been implicated in the regulation of sodium excretion, we investigated the hypothesis that the renal prostaglandin system participates in "pressure natriuresis." Anesthetized sodium-replete dogs were subjected to partial carotid artery constriction to elevate systemic arterial pressure. Under these control conditions, sodium excretion was 103 +/- 18 mueq/min (n = 17) and urinary prostaglandin E2 excretion averaged 4.6 +/- 1.5 ng/min (n = 8). Decreases in renal arterial pressure within the auto-regulatory range reduced sodium excretion (2.1%/mmHg) and prostaglandin E2 excretion (1.7%/mmHg), whereas GFR and RBF were not affected. There was a significant correlation between the changes in sodium and prostaglandin E2 excretion rates (r = 0.932, P less than 0.01). In nine dogs treated with indomethacin, sodium excretion was reduced by 70% while GFR and autoregulatory capability were unaffected. There was a marked attenuation of the effect of changes in arterial pressure on sodium excretion, with this parameter exhibiting changes averaging 0.6%/mmHg (P less than 0.001). These observations suggest that the renal prostaglandin system may exert an important influence on the pressure-natriuresis mechanism.

Previous studies in adrenalectomized (Adx) rats suggest that aldosterone may regulate ion transport in the ascending portion of Helen's loop. In order to examine directly the effect of adrenalectomy on transport, medullary thick ascending limb (Mtal) segments were isolated from Adx, Adx replaced with aldosterone (Adx + Ald, 0.5 micrograms X 100 g X body wt X d), and control Sprague-Dawley rats. Both net sodium and net chloride fluxes were significantly less in the Mtal segments from Adx rats compared with those in the control or Adx + Ald group. Physiologic levels of exogenous aldosterone increased net sodium chloride flux toward control values in the Adx + Ald group. Net potassium flux was not different among the three groups. We conclude that adrenalectomy impairs reabsorptive NaCl but not K transport in the Mtal, and that aldosterone restores this process. This reabsorptive defect may contribute to the urinary concentrating and diluting abnormality associated with adrenal insufficiency.

This review focuses on the hypothesis that potassium is recycled in the medulla by secretion into the pars recta or descending limb of long-looped nephrons and reabsorption from the ascending limb and/or medullary collecting duct. Evidence supporting the recycling hypothesis is summarized and the process is analyzed quantitatively by an examination of the mass flow of potassium reaching different sites along superficial and juxtamedullary nephrons and collecting tubules. From differences in potassium mass flow between sites, we have estimated the amount of potassium that must be secreted or absorbed by individual segments of the renal tubule. These rates of secretion and absorption are compared with the potassium transport characteristics of the respective segments, as assessed by isolated tubule perfusion in vitro and micropuncture in vivo. It is apparent that potassium secretion can occur passively in the pars recta and descending limb of long-looped nephrons as a consequence of the elevated potassium concentration in the medullary interstitium. At present, no active potassium absorptive mechanism has been demonstrated in any segment of the ascending limb. Due to the very high ionic permeability of the thin ascending segment and the lumen-positive transepithelial voltage in the thick ascending segment, however, considerable passive absorption likely occurs, although net potassium secretion has also been demonstrated in the cortical thick ascending limb. The high potassium concentration in the inner medullary interstitium and the difference in mass flow of potassium between the end of superficial nephrons in the cortex and the collecting ducts in the papilla, at least under certain circumstances, are best accounted for by net potassium reabsorption in the medullary collecting duct.

The document defines the terms most commonly encountered in the field of polymer reactions and functional polymers. The scope has been limited to terms that are specific to polymer systems. The document is organized into three sections. The first defines the terms relating to reactions of polymers. Names of individual chemical reactions are omitted from the document, even in cases where the reactions are important in the field of polymer reactions. The second section defines the terms relating to polymer reactants and reactive polymeric materials. The third section defines the terms describing functional polymeric materials.