bluuebunny/crossref_metadata_2025_split huggingface dataset:
Advanced Materials and Manufacturing Technology Developments for Extreme Environment Gas Turbine Applications
Authors: Kulkarni Anand , James Allister , Kamel Ahmed 
Published: April 2021

Abstract
Electrical power generation is becoming increasingly reliant on gas turbines with multiple fuel capability, with research advances focusing on increased efficiency/power output and reduced emissions. Increasing gas turbine efficiency primarily requires higher operating temperatures and reduced coolant flow in the turbine flow path, which makes it challenging to increase component performance, as these will encounter high stresses and large temperature gradients. Current nickel-based alloys, which operate at operate at extreme environments, are exposed to stress caused by temperature or static/dynamic loading like creep and fatigue, oxidation and corrosion, wear, and damage due to vibrations. Higher turbine inlet temperatures are currently managed with internal/film cooling and thermal/environmental barrier coatings for hot section parts. Comprehensive solutions are needed to translate to achieve ultrahigh efficiencies, lower parts cost, reduced scrape rate, and life cycle savings. The paper discusses material developments coupled with innovative manufacturing approaches to be married with advanced design strategies to realize the needed improvements for hot gas path components. The case studies for combustion and turbine components will be presented to demonstrate the structure property relationships and improved component performance at lower cost.
Survival Trends and Syndromic Esophageal Atresia
Authors: Tan Tanny Sharman P. , Beck Cara , King Sebastian K. , Hawley Alisa , Brooks Jo-Anne , McLeod Elizabeth , Hutson John M. , Teague Warwick J. 
Published: April 2021

BACKGROUND AND OBJECTIVES:
Presence of a syndrome (or association) is predictive of poor survival in esophageal atresia (EA). However, most reports rely on historical patient outcomes, limiting their usefulness when estimating risk for neonates born today. We hypothesized improved syndromic EA survival due to advances in neonatal care.

METHODS:
A retrospective single-center review of survival in 626 consecutive patients with EA from 1980 to 2017 was performed. Data were collected for recognized risk factors: preterm delivery; birth weight &lt;1500 g; major cardiac disease; vertebral defects, anal atresia, cardiac defects, tracheoesophageal fistula, renal anomalies, and limb abnormalities (VACTERL); and non-VACTERL syndromes. Cox proportional hazards regression models were used to evaluate temporal trends in survival with respect to year of birth and syndromic EA.

RESULTS:
Overall, 87% of 626 patients with EA survived, ranging from 82% in the 1980s to 91% in the 2010s. After adjusting for confounders, syndromic EA survival did not improve during the study, with no association found between year of birth and survival (hazard ratio [HR] 0.98, 95% confidence interval [CI]: 0.95–1.01). Aside from lethal non-VACTERL syndromes, patients with nonlethal non-VACTERL syndromes (HR 6.85, 95% CI: 3.50–13.41) and VACTERL syndrome (HR 3.02, 95% CI: 1.66–5.49) had a higher risk of death than those with nonsyndromic EA.

CONCLUSIONS:
Survival of patients with syndromic EA has not improved, and patients with non-VACTERL syndromes have the highest risk of death. Importantly, this is independent of syndrome lethality, birth weight, and cardiac disease. This contemporary survival assessment will enable more accurate perinatal counseling of parents of patients with syndromic EA.
Novel C5-Dependent Mechanism of Neutrophil Stimulation by Bioincompatible Dialyzer Membranes
Authors: ROSENKRANZ ALEXANDER R. , KÖRMÖCZI GÜNTHER F. , THALHAMMER FLORIAN , MENZEL ERNST J. , HÖRL WALTER H. , MAYER GERT , ZLABINGER GERHARD J. 
Published: April 2021

Abstract.
The objective of the study was to evaluate the contribution of reactive oxygen intermediate formation for receptor modulation on neutrophils by the cellulosic dialyzer membrane cuprophan (CU). In patients dialyzed with CU, CD11b and CD66b upregulation on neutrophils (by 104.3 ± 37.9% and 85.7 ± 31.1%, respectively), and a downregulation of L-selectin (by 44.9 ± 26.9%) was seen, whereas expression of CD11 a remained unaltered. Hemodialysis with polysulfone did not bring about major changes in surface receptor expression. In vitro incubation of isolated neutrophils in the presence of serum with hollow fibers of CU or polysulfone showed similar results: Only CU resulted in upregulation of CD11b and CD66b expression (by 65.5 ± 18.7% and 60.1 ± 24%) and a decrease in CD62L expression (by 60.6 ± 18.2%). In contrast to receptor alterations, generation of reactive oxygen intermediate by CU occurred in the absence of serum. Inhibition experiments with soluble complement receptor 1, which produced only partial inhibition of receptor up-/down-regulation, indicated the existence of also other than alternate complement-dependent mechanisms for neutrophil activation. By using C5-depleted serum instead of normal human serum, up-/down-regulation of CD11b, CD62L, and CD66b by CU was dramatically reduced, whereas C3-depleted serum did not produce that effect. C5-deficient serum repleted with purified C5, as well as purified C5 alone, was able to induce receptor modulation by CU comparable to normal human serum. L-Methionine, a specific inhibitor for the oxidative activation of C5, blocked the modulatory effect of CU in assays with purified C5 as well as with serum. As a result, in addition to the alternative pathway of complement, a C5-dependent mechanism probably activated by neutrophil-derived reactive oxygen intermediate leads to receptor modulation and subsequent generation of the well known side effects of bioincompatible dialyzer membranes.
Expression of 25-Hydroxyvitamin D3-1α-Hydroxylase in the Human Kidney
Authors: ZEHNDER DANIEL , BLAND ROSEMARY , WALKER ELIZABETH A. , BRADWELL ARTHUR R. , HOWIE ALEXANDER J. , HEWISON MARTIN , STEWART PAUL M. 
Published: April 2021

Abstract.
The secosteroid hormone 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) plays a vital role in calcium metabolism, tissue differentiation, and normal bone growth. Biosynthesis of 1,25(OH)2D3 is catalyzed by the mitochondrial cytochrome P450 enzyme 25-hydroxyvitamin D3 1α-hydroxylase (1α-hydroxylase). Although activity of this enzyme has been described in several tissues, the kidneys are recognized to be the principal site of 1,25(OH)2D3 production. To date, enzyme activity studies using vitamin D-deficient animals have suggested that 1α-hydroxylase is expressed exclusively in proximal convoluted tubules. With the recent cloning of 1α-hydroxylase, specific cRNA probes and in-house polyclonal antiserum have been used to determine the distribution of 1α-hydroxylase along the human nephron. Immunohistochemistry and in situ hybridization studies indicated strong expression of 1α-hydroxylase protein and mRNA in the distal convoluted tubule, the cortical and medullary part of the collecting ducts, and the papillary epithelia. Lower expression was observed along the thick ascending limb of the loop of Henle and Bowman's capsule. Weaker and more variable expression of 1α-hydroxylase protein and mRNA was seen in proximal convoluted tubules, and no expression was observed in glomeruli or vascular structures. These data show for the first time the distribution of 1α-hydroxylase expression in normal human kidney. In contrast to earlier enzyme activity studies conducted in vitamin D-deficient animals, our data indicate that the distal nephron is the predominant site of 1α-hydroxylase expression under conditions of vitamin D sufficiency.
Mechanism of Increased Parathyroid Hormone mRNA in Experimental Uremia
Authors: YALCINDAG CEVDET , SILVER JUSTIN , NAVEH-MANY TALLY 
Published: April 2021

Abstract.
Patients with chronic renal failure develop secondary hyperparathyroidism with increased synthesis and secretion of parathyroid hormone (PTH) resulting in severe skeletal complications. In rats with secondary hyperparathyroidism due to 5/6 nephrectomy, there are increased PTH mRNA levels, and this mechanism was studied. Parathyroid glands were micro-dissected from control and 5/6 nephrectomy rats and analyzed for PTH mRNA and control genes, and the nuclei were used for nuclear run-on experiments. The cytosolic proteins of the parathyroids were used to study PTH mRNA protein binding by ultraviolet cross-linking and the degradation of the PTH transcript in vitro. Nuclear run-ons showed that the increase in PTH mRNA levels was posttranscriptional. Protein binding to the PTH mRNA 3′-UTR determines PTH mRNA stability and levels. Parathyroid proteins from uremic rats bound PTH mRNA similar to control rats by ultraviolet cross-linking. To determine the effect of uremia on PTH mRNA stability, an in vitro RNA degradation assay was performed with parathyroid proteins from uremic rats. When parathyroid proteins from control rats were incubated with PTH mRNA, there was transcript degradation already at 30 min, reaching 50% at 60 min and 90% at 180 min. With uremic parathyroid proteins, the PTH mRNA was not degraded at all at 120 min and was moderately decreased at 180 min. This decrease in degradation by uremic parathyroid proteins suggests a decrease in parathyroid cytosolic endonuclease activity in uremia resulting in a more stable PTH transcript. The increased PTH mRNA levels would translate into increased PTH synthesis and serum PTH levels, which would lead to metabolic bone disease in many patients with chronic renal failure.
Renal Function in Mice
Authors: CERVENKA LUDEK , MITCHELL KENNETH D. , NAVAR L. GABRIEL 
Published: April 2021

Abstract.
The present study was performed to validate a simple means for assessing renal function in anesthetized mice and to characterize the renal hemodynamic responses to acute volume expansion and how these responses are altered by concurrent angiotensin II (AngII) infusions. Inulin and para-aminohippurate clearances were used to assess GFR and renal plasma flow (RPF) in three groups of male C57B1/6 mice anesthetized with inactin (100 mg/kg, intraperitoneally) and ketamine (10 mg/kg). To avoid the hypotension associated with repeated blood sampling, a single blood sample was taken after three timed urine collections. Renal function and mean arterial pressure (MAP) were measured under euvolemic conditions (2.5 μl/min, intravenously, n = 7) during isotonic saline volume expansion (12.5 μl/min, intravenously, n = 5) and during volume expansion with concurrent AngII infusion (5 ng/min · g, n = 5). MAP in the control group was 77 ± 2 mmHg; volume expansion alone did not change MAP significantly (83 ± 2 mmHg), but led to significantly greater values in both GFR and RPF (1.35 ± 0.14 versus 1.01 ± 0.1 ml/min · g and 11.26 ± 1.39 versus 6.29 ± 0.5 ml/min · g, respectively). Infusion of AngII during volume expansion led to significant elevations of MAP (100 ± 3 mmHg, P < 0.05) and prevented the increases in GFR and RPF elicited by volume expansion (0.77 ± 0.08 and 5.35 ± 0.48 ml/min · g, respectively). Volume expansion also elicited marked increases in absolute and fractional sodium excretion (6.1 ± 1.0 versus 0.62 ± 0.2 μEq/min · g and 3.1 ± 0.7 versus 0.4 ± 0.1%, respectively). AngII infusion attenuated the absolute and fractional sodium excretion responses to volume expansion (3.4 ± 1.2 μEq/min · g and 2.5 ± 0.5%, respectively). The present findings demonstrate that anesthetized mice exhibit marked renal hemodynamic and excretory responses to isotonic saline volume expansion. Concomitant AngII infusion attenuates these responses in spite of greater increases in arterial pressure.
Prevalence and Clinical Outcome Associated with Preexisting Malnutrition in Acute Renal Failure
Authors: FIACCADORI ENRICO , LOMBARDI MARIA , LEONARDI SABINA , ROTELLI CARLO FEDERICO , TORTORELLA GIOVANNI , BORGHETTI ALBERICO 
Published: April 2021

Abstract.
Malnutrition is a frequent finding in hospitalized patients and is associated with an increased risk of subsequent in-hospital morbidity and mortality. Both prevalence and prognostic relevance of preexisting malnutrition in patients referred to nephrology wards for acute renal failure (ARF) are still unknown. This study tests the hypothesis that malnutrition is frequent in such clinical setting, and is associated with excess in-hospital morbidity and mortality. A prospective cohort of 309 patients admitted to a renal intermediate care unit during a 42-mo period with ARF diagnosis was studied. Patients with malnutrition were identified at admission by the Subjective Global Assessment of nutritional status method (SGA); nutritional status was also evaluated by anthropometric, biochemical, and immunologic parameters. Outcome measures included in-hospital mortality and morbidity, and use of health care resources. In-hospital mortality was 39% (120 of 309); renal replacement therapies (hemodialysis or continuous hemofiltration) were performed in 67% of patients (206 of 309); APACHE II score was 23.1 ± 8.2 (range, 10 to 52). Severe malnutrition by SGA was found in 42% of patients with ARF; anthropometric, biochemical, and immunologic nutritional indexes were significantly reduced in this group compared with patients with normal nutritional status. Severely malnourished patients, as compared to patients with normal nutritional status, had significantly increased morbidity for sepsis (odds ratio [OR] 2.88; 95% confidence interval [CI], 1.53 to 5.42, P < 0.001), septic shock (OR 4.05; 95% CI, 1.46 to 11.28, P < 0.01), hemorrhage (OR 2.98; 95% CI, 1.45 to 6.13, P < 0.01), intestinal occlusion (OR 5.57; 95% CI, 1.57 to 19.74, P < 0.01), cardiac dysrhythmia (OR 2.29; 95% CI, 1.36 to 3.85, P < 0.01), cardiogenic shock (OR 4.39; 95% CI, 1.83 to 10.55, P <.001), and acute respiratory failure with mechanical ventilation need (OR 3.35; 95% CI, 3.35 to 8.74, P < 0.0.5). Hospital length of stay was significantly increased (P < 0.01), and the presence of severe malnutrition was associated with a significant increase of in-hospital mortality (OR 7.21; 95% CI, 4.08 to 12.73, P < 0.001). Preexisting malnutrition was a statistically significant, independent predictor of in-hospital mortality at multivariable logistic regression analysis both with comorbidities (OR 2.02; 95% CI, 1.50 to 2.71, P < 0.001), and with comorbidities and complications (OR 2.12; 95% CI, 1.61 to 2.89, P < 0.001). Malnutrition is highly prevalent among ARF patients and increases the likelihood of in-hospital death, complications, and use of health care resources.
Clinical Practice Guidelines in End-Stage Renal Disease
Authors: KLIGER ALAN S. , HALEY WILLIAM E. 
Published: April 2021

Abstract.
Clinical practice guidelines (CPGs) for end-stage renal failure (ESRD) were recently published, and represent a comprehensive review of available literature and the considered judgment of experts in ESRD. To prioritize and implement these guidelines, the evidence underlying each guideline should be ranked and the attributes of each should be defined. Strategies to improve practice patterns should be tested. Focused information for each high priority guideline should be disseminated, including a synopsis and assessment of the underlying evidence, the evidence model used to develop that guideline, and suggested strategies for CPG implementation. Clinical performance measures should be developed and used to measure current practice, and the success of changing practice patterns on clinical outcomes. Individual practitioners and dialysis facilities should be encouraged to utilize continuous quality improvement techniques to put the guidelines into effect. Local implementation should proceed at the same time as a national project to convert high priority CPGs into clinical performance measures proceeds. Patients and patient care organizations should participate in this process, and professional organizations must make a strong commitment to educate clinicians in the methodology of CPG and performance measure development and the techniques of continuous quality improvement. Health care regulators should understand that CPGs are not standards, but are statements that assist practitioners and patients in making decisions.
Stereologic Methods and Their Application in Kidney Research
Authors: NYENGAARD JENS R. 
Published: April 2021

Abstract.
Stereologic methods are used to obtain quantitative information about three-dimensional structures based on observations from section planes or—to a limited degree—projections. Stereologic methods, which are used in biologic research and especially in the research of normal and pathologic kidneys, will be discussed in this review. Special emphasis will be placed on modern stereologic methods, free of assumptions of the structure, size, and shape, etc., so-called UFAPP (unbiased for all practical purposes) stereologic methods. The basic foundation of all stereology, sampling, will be reviewed in relation to most of the methods discussed. Estimation of error variances and some of the basic problems in stereology will be reviewed briefly. Finally, a few comments will be made about the future directions for stereology in kidney research.
Donor G Protein β3 Subunit 825TT Genotype Is Associated with Reduced Kidney Allograft Survival
Authors: BEIGE JOACHIM , ENGELI STEFAN , RINGEL JENS , OFFERMANN GERD , DISTLER ARMIN , SHARMA ARYA M. 
Published: April 2021

Abstract.
Recent studies have identified a novel polymorphism (C825T) of the gene encoding the β3 subunit of heterotrimeric G proteins (Gβ3), associated with enhanced activation of G proteins, which appears to be more common in hypertensive patients. In the present study, the relationship between this genetic variant and kidney allograft survival was examined over the first 3 yr after transplantation, in 320 consecutive Caucasian patients recruited from the Berlin-Steglitz transplantation center between 1988 and 1993. Clinical parameters, transplantation data, and details of graft survival were retrieved from clinical records. After multivariate adjustment for covariates (Cox hazard regression), the Gβ3 825TT donor-genotype was associated with a significantly decreased graft survival representing a relative risk of graft loss of 2.2 (95% confidence interval, 1.1 to 4.8) compared to TC and CC grafts within the observation period. This association between donor TT genotype and graft survival remained stable even after stepwise exclusion of covariates from the multivariate model. In contrast, there was no significant relationship between recipient genotype and allograft function. These findings indicate that individuals receiving renal allografts from donors homozygous for the Gβ3-825T allele may have an increased risk of developing allograft failure. Additional studies on the role of this genetic marker as well as the role of pertussis toxin-sensitive G proteins in the development of chronic rejection appear warranted.
Renal Expression of Aquaporins in Liver Cirrhosis Induced by Chronic Common Bile Duct Ligation in Rats
Authors: FERNÁNDEZ-LLAMA PATRICIA , TURNER RACHEL , DIBONA GERALD , KNEPPER MARK A. 
Published: April 2021

Abstract.
Semiquantitative immunoblotting was used to investigate the expression levels of the four major renal aquaporins, the Na-K-2Cl cotransporter of the thick ascending limb, the type 3 Na-H exchanger, and the Na-K-ATPase in kidneys from rats with cirrhosis secondary to common bile duct ligation (CBDL). These rats had significant water retention and hyponatremia. In contrast to models of cirrhosis induced by carbon tetrachloride, aquaporin-2 expression in CBDL-induced cirrhosis was decreased. Thus, these results show that in the setting of extracellular fluid volume expansion, excessive water retention with hyponatremia can occur in the absence of increases in aquaporin-2 abundance. In addition, the expression levels of the two basolateral collecting duct aquaporins (aquaporin-3 and -4) were decreased in CBDL rats relative to sham-operated control rats. Similarly, the Na-K-2Cl cotransporter of the thick ascending limb and the type 3 Na-H exchanger showed decreases in expression. In contrast, the expression levels of aquaporin-1 and the α1 subunit of the Na-K-ATPase were not decreased. Thus, dysregulation of multiple water channels and ion transporters may play a role in water balance abnormalities associated with CBDL-induced cirrhosis in rats.
Apoptosis of Tubular Epithelial Cells in Donor Kidney Biopsies Predicts Early Renal Allograft Function
Authors: OBERBAUER RAINER , ROHRMOSER MANUELA , REGELE HEINZ , MÜHLBACHER FERDINAND , MAYER GERT 
Published: April 2021

Abstract.
Acute renal failure (ARF) is a serious complication in the early postoperative period after kidney transplantation. In an effort to identify subjects at risk, several donor-, recipient-, and procedure-related factors have been studied. Because no morphologic parameter predictive of delayed graft function has been identified to date, this study was conducted to determine whether the number of apoptotic cells in donor biopsies obtained before engraftment is predictive of the development of posttransplant ARF. Donor biopsies of patients with “biopsyproven” acute tubular damage but no signs of rejection (n = 23) showed significantly higher counts of apoptotic tubular epithelial cells when compared to patients with immediate transplant function (n = 44) or early rejection (n = 22). In all groups, a significantly higher percentage of apoptotic cells was found in the distal compared to the proximal tubule. The expression of bcl-2 and proliferating cell nuclear antigen was not different among the groups. Late allograft function was not affected by early ARF as serum creatinine values were similar in all three groups after 6 mo. These data suggest that the number of apoptotic renal tubular epithelial cells in donor biopsies before engraftment is predictive of the early postoperative course in patients undergoing kidney transplantation.
Cytotoxicity of Antiviral Nucleotides Adefovir and Cidofovir Is Induced by the Expression of Human Renal Organic Anion Transporter 1
Authors: HO EDMUND S. , LIN DEBORAH C. , MENDEL DIRK B. , CIHLAR TOMAS 
Published: April 2021

Abstract.
The transport of organic anions in proximal convoluted tubules plays an essential role in the active secretion of a variety of small molecules by the kidney. In addition to other anionic substrates, the human renal organic anion transporter 1 (hOAT1) is capable of transporting the nucleotide analogs adefovir and cidofovir. To investigate the involvement of hOAT1 in the mechanism of nephrotoxicity associated with these two clinically important antiviral agents, Chinese hamster ovary (CHO) cells were stably transfected with hOAT1 cDNA. The resulting CHOhOAT cells showed probenecid-sensitive and pH-dependent uptake of p-aminohippurate (K
m = 15.4 μM, V
max = 20.6 pmol/106 cells · min), a prototypical organic anion substrate. In addition, the stably expressed hOAT1 mediated efficient transport of adefovir (K
m = 23.8 μM, V
max = 46.0 pmol/106 cells · min) and cidofovir (K
m = 58.0 μM, V
max = 103 pmol/106 cells · min) such that the levels of intracellular metabolites of both nucleotides were >100-fold higher in CHOhOAT cells than in parental CHO. Consequently, adefovir and cidofovir were approximately 500-fold and 400-fold more cytotoxic, respectively, in CHOhOAT cells compared to CHO. The cytotoxicity of both drugs in CHOhOAT cells was markedly reduced in the presence of hOAT1 inhibitors. The cyclic prodrug of cidofovir, which exhibits reduced in vivo nephrotoxicity, was a poor substrate for hOAT1 and showed only marginally increased cytotoxicity in CHOhOAT cells. In conclusion, these studies demonstrate that hOAT1 plays a critical role in the organ-specific toxicity of adefovir and cidofovir, and indicates that CHOhOAT cells may represent a useful in vitro model to investigate the potential nephrotoxicity of clinically relevant organic anion agents.