bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gut and liver handling of asymmetric and symmetric dimethylarginine in the rat under basal conditions and during endotoxemia
Authors: Nijveldt Robert J. , Siroen Michiel P. C. , Teerlink Tom , Van Lambalgen Antonie A. , Rauwerda Jan A. , Van Leeuwen Paul A. M. 
Published: October 2004

Abstract: Introduction/Aim: Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide (NO) synthase enzymes, whereas symmetric dimethylarginine (SDMA) competes with arginine transport. Although both dimethylarginines may be important regulators of the arginine‐NO pathway, their metabolism is largely unknown. In previous studies, evidence was found for the liver in the metabolism of dimethylarginines. We aimed to investigate dimethylarginine handling of the gut and the liver in detail under basal conditions and during endotoxemia.Methods: Twenty‐one male Wistar rats were used for this study. Endotoxemia was induced by lipopolysaccharide (LPS) infusion (8 mg/kg). Blood flow was measured using radiolabeled microspheres according to the reference sample method. Concentration of dimethylarginines were measured by high‐performance liquid chromatography. The combination of arteriovenous concentration difference and organ blood flow allowed calculation of net organ fluxes and fractional extraction (FE) rates.Results: Arterial plasma concentration of ADMA was lower in LPS rats, in contrast to a higher SDMA concentration. For the gut, net release of ADMA was found, which was higher in LPS rats. In contrast, for the gut, net uptake of SDMA was found, which was lower in LPS rats. For the liver, a high net uptake of ADMA was found in both groups, while FE was significantly increased in LPS rats. Hepatic handling of SDMA was negligible.Conclusion: The liver plays an important role in eliminating ADMA from the circulation and endotoxemia stimulates this capacity. In contrast to the liver, the gut releases ADMA. Endotoxemia results in a reduced systemic ADMA concentration.
Implication of inflammation‐related cytokines in the natural history of liver cirrhosis
Authors: Girón‐González José A. , Martínez‐Sierra Carmen , Rodriguez‐Ramos Claudio , Macías Manuel A. , Rendón Paloma , Díaz Fernando , Fernández‐Gutiérrez Clotilde , Martín‐Herrera Leopoldo 
Published: October 2004

Abstract: Background/Aims: Increased serum concentrations of pro‐inflammatory cytokines have been detected in patients with liver cirrhosis. However, their role in the natural history of cirrhosis and portal hypertension, in the absence of infection, and the prognostic significance of inflammation‐related cytokines have not been reported. Our objective was the analysis of the prognostic value of inflammation‐related cytokines in cirrhotic patients.Patients and methods: Serum concentrations of tumor necrosis factor (TNF‐α) and its soluble receptors I and II and interleukin 6 (IL‐6), as well as mean blood pressure, plasma renin activity, aldosterone, vasopressin and norepinephrine concentrations were determined in 72 cirrhotic patients (Child–Pugh score: A 50%, B 33.3%, C 16.7%), without any evidence of infection, and in 25 healthy controls. Patients were followed up for a median of 35.9 (range 6–60) months.Results: Increased concentrations of soluble TNF receptors were detected in cirrhotic patients when compared with healthy controls. TNF receptors and IL‐6 concentrations were both significantly more elevated in advanced phases of cirrhosis (Child–Pugh score C vs B and vs A). Sixteen patients died as a related consequence of liver cirrhosis. Multivariant analysis demonstrated that Child–Pugh score, mean blood pressure and serum levels of TNF receptor I were associated with mortality.Conclusions: In addition to the classic factors implicated in mortality (Child–Pugh score and hemodynamic parameters), alterations in inflammation‐related components are of prognostic significance in cirrhotic patients.
The role of midkine and pleiotrophin in liver regeneration
Authors: Ochiai Keiko , Muramatsu Hisako , Yamamoto Satoshi , Ando Hisami , Muramatsu Takashi 
Published: October 2004

Abstract: Background/Purpose: We studied roles of two closely related heparin‐binding growth factors, midkine (MK) and plieotrophin (PTN) in the processes of liver regeneration after partial hepatectomy.Methods: Liver regeneration was comparatively analyzed using mice deficient in the MK gene (Mdk), mice deficient in the pleiotrophin gene (Ptn) and wild‐type mice.Results: Migration of neutrophils and macrophages to the liver 1–5 days after partial hepatectomy was suppressed in Mdk (−/−) mice. Liver damage as assessed by serum aspartate aminotransferase was also less severe in the deficient mice. On the other hand, cell growth in the liver was generally suppressed in the deficient mice 3–14 days after partial hepatectomy. The weight of the liver 7 and 14 days after partial hepatectomy was significantly less in Mdk (−/−) mice than wild‐type mice. Very similar results were obtained using Ptn (−/−) mice except that a significant difference in the repaired liver weight was not observed between Ptn (−/−) mice and wild‐type mice.Conclusions: MK and PTN are involved both in the inflammatory and reparative processes after partial hepatectomy, and as a whole are beneficial for liver regeneration.
Kinetic analysis of daily hemofiltration
Authors: Yamashita Akihiro C , Kawanishi Hideki 
Published: October 2004

AbstractBackground:  Daily hemofiltration (D‐HF) is a new treatment modality that shows unique solute removal characteristics and possibly provides a high quality of life for patients with end‐stage renal disease. We evaluated solute removal characteristics of D‐HF for five patients by kinetic modeling analysis.Methods:  Five patients treated with normal 3 × 4 hr/week hemodialysis (HD) were switched to D‐HF (6 × 2 hr/week). Ultrafiltration rates (QF) or small‐solute clearances ranged from 63 to 106 mL/min. All the necessary kinetic parameters were determined from patients' physical data and HD portion of the clinical measurements. The two‐compartment kinetic model predicted the concentration changes after switching from normal HD to D‐HF.Results:  Concentrations of small solutes such as urea nitrogen (UN) increased, whereas that of β2‐microglobulin (β2‐MG) decreased after switching from normal HD to D‐HF in all five patients. Predicted solute concentrations and clinical measurements for UN and β2‐MG were in good agreement with mean error less than 10%. The model predicted that QF = 155 mL/min may be necessary for time‐averaged concentration (TAC) of UN to be unchanged. The model also predicted that the 7 times/week D‐HF should not increase the pretreatment concentration of UN, expecting even much lower β2‐MG concentration after switching from normal HD to D‐HF.Conclusion:  D‐HF is superior to normal HD for removing larger solutes but may increase the TAC of small solutes. Seven‐day (7 times/week) D‐HF may improve the solute removal capacity of small solutes.
Associations with home hemodialysis modality failure and mortality
Authors: Young Bessie A , Hynes Janey , McComb Timothy , Blagg Christopher R 
Published: October 2004

AbstractBackground: Limited data exist on risk factors for home hemodialysis (HH) failure and mortality. We sought to determine whether age, helper status, or ethnicity was associated with home dialysis failure or mortality.Methods: We conducted a retrospective cohort study of all prevalent and incident patients from a regional dialysis unit who initiated HH training from December 2000 to September 2002. Baseline demographics, program entry and exit dates, and mortality were ascertained. Characteristics of those more likely to remain in the program were assessed using logistic regression; survival was determined using Cox proportional hazards models.Results: Of the 1117 patients enrolled for dialysis, 116 patients were trained in the HH program (6.8%). Of those, 45.7% remained in the program, 10.3% received a transplant, 10.3% returned to in‐center dialysis, 1.7% were lost to follow‐up, and 31.7% expired. Compared to patients who returned to center or received a transplant, patients who remained on HH were more likely to be older, to have been on dialysis longer, and to have diabetes as their primary renal disease. Ethnicity, sex, or type of helper did not affect home program status. Among those who remained in the HH program, those with hypertension or other renal diseases had better survival than those with diabetes, as did those who had related helpers compared to those with unrelated helpers.Conclusions: Older and younger ages, but not ethnicity, helper status, or sex, were associated with home dialysis failure. Diabetes remained an independent risk factor for increased mortality. HH remains a viable option for many patients.
Six years of experience with nightly home hemodialysis access
Authors: Pipkin Mary , Craft Viola , Spencer Maureen , Lockridge Robert S 
Published: October 2004

AbstractBackground:  Lynchburg Nephrology Dialysis Incorporated started its nightly home hemodialysis (NHHD) program in September 1997.Purpose:  The purpose of this study was to evaluate episodes of exit‐site infections, catheter sepsis, and safety and longevity of accesses for patients doing NHHD.Method:  If internal jugular (IJ) catheter was chosen, the patient was started on 2 mg coumadin per day when catheter was placed. If catheter malfunctioned, it was blocked with a thrombolytic agent and coumadin was adjusted to meet a goal international normalized ratio (INR) of 1.5 to 2.25. If the problem persisted, the catheter was exchanged. For catheters, a threaded lock cannula (BD InterLink device, BD) was used to prevent air emboli and infections and a locking device was used to prevent disconnects. If arteriovenous (AV) fistula was used, four buttonholes were established using 16‐gauge needles. If AV graft was used, patients were taught the rope ladder cannulation technique using 16‐gauge needles.Results:  As of September 1, 2003, 45 patients have completed training and have performed 27,063 treatments at home. Total catheter time at home was 930 months. Total AV fistula and AV graft times at home were 190 and 20 months, respectively. Upon completion of training, 34 patients were using tunneled IJ catheters, 10 were using AV fistulas, and 1 was using an AV graft. The IJ catheter exit‐site and sepsis infection rates were 0.35 and 0.52 episodes per 1000 patient‐days, respectively. Mean catheter life was 8.5 months with the longest being 66.7 months and the shortest being 0.2 months. The AV fistula and graft exit‐site and sepsis infection rates were 0.16 and 0 episodes per 1000 patient‐days, respectively. Catheter complications included one episode of disconnect due to patient's failure to use the locking device, one episode of central stenosis, and one episode of intracranial hemorrhage, due to prolonged INR, with resolution of symptoms.Conclusion:  Data support the fact that tunneled IJ catheters, AV fistulas, and AV grafts are effective and safe permanent accesses for patients on NHHD.
The International Quotidian Hemodialysis Registry: Rationale and methods
Authors: Nesrallah Gihad E , Suri Rita S , Garg Amit X , Moist Louise M , Awaraji Christian , Lindsay Robert M ,   the Frequent Dialysis Regimens Workgroup
Published: October 2004

AbstractThe HEMO study has provided evidence that a higher dialysis dose per session does not improve survival in conventional three times a week hemodialysis (HD). Attention has therefore shifted to HD schedules that vary in frequency and/or duration of dialysis. Although observational data favoring the use of frequent dialysis are steadily accumulating, compelling evidence supporting its superiority is still lacking. Several advances have recently been made with a view to put this form of therapy on much more solid footing. Upcoming research initiatives including clinical trials of frequent HD and the quotidian HD registry will provide a wealth of analytic and descriptive data that will help define the role for frequent HD regimens as a therapy for end‐stage renal disease.
Peptide‐coated vascular grafts: An in vivo study in sheep
Authors: Li Cheng , Hill Arthur , Imran Mir , Tio Fermin 
Published: October 2004

AbstractThe data on function and patency of prosthetic vascular grafts in various clinical settings are limited. The purpose of this in vivo study was to compare the function and patency of P15‐coated expanded polytetrafluoroethylene (ePTFE) vascular grafts to uncoated ePTFE grafts in sheep. The P15 cell‐binding peptide was covalently immobilized onto the surface of ePTFE grafts by a novel atmospheric plasma coating method. We evaluated the amount of neointimal tissue ingrowth present at the arterial and venous sides of the anastomoses and the degree of endothelial cell resurfacing of the luminal surface of the graft. Four P15‐coated grafts and two control grafts were implanted as arteriovenous grafts between the femoral artery and vein and the carotid artery and jugular vein in two sheep (n = 6). One animal was euthanized after 14 days and the other after 28 days. The study showed the intimal ingrowth was significantly less. The average intimal thickness of P15‐coated grafts (658 µm) was approximately two and a half times less than that of uncoated samples (1657 µm). The newly formed endothelial cell lining was thicker and its coverage was more uniform for P15‐coated grafts compared to the uncoated controls.
Blood compatibility and filtration characteristics of a newly developed polyester polymer alloy membrane
Authors: Yamashita Akihiro C , Tomisawa Narumi , Takezawa Azusa , Sakurai Kenji , Sakai Tadasu 
Published: October 2004

AbstractBackground:  Many synthetic polymeric membranes have been widely used for blood purification therapies for removing larger solutes and for better blood compatibility.Methods:  Five different filters with polyester polymer alloy (PEPA) membrane (Nikkiso) that included polyvinylpyrrolidone (PVP), that is, standard‐pore‐size FLX (PEPA with PVP(–)), standard‐pore‐size FDX (PEPA with PVP(+)), new FDX (PEPA with PVP(++)), larger‐pore‐size FDY (PEPA with PVP(+)), and new FDY (PEPA with PVP(++)), were evaluated in terms of in vivo blood compatibility and aqueous in vitro sieving coefficient (s.c.) for albumin.Results:  FDY showed excellent small changes in C3a concentration during the treatment right after switching from polysulfone membrane, leaving no significant changes in other blood‐compatible indices. New FDY, in contrast, showed less biocompatible characteristics in terms of C3a, which may be caused by increased use of PVP. FLX (no PVP) showed the highest s.c. for albumin. With a hydrophilic agent (PVP), the s.c. was greatly reduced in FDX. By enlarging the pore diameter in FDY, the s.c. increased in accordance with the enlargement. Generally speaking, polysulfone filters with PVP(+++) reach the peak s.c. value approximately 10 min after starting the experiment. The s.c. of the PEPA membrane with no or small amount of PVP, which showed excellent blood compatibility, never showed peaks, whereas the peak s.c. values were found in new PEPA with increased amount of PVP that showed higher C3a changes.Conclusions:  The separation characteristics of aqueous albumin may be related to its blood compatibility.
Cuffed‐catheter‐related Lemierre syndrome
Authors: Hennigan Allison , Collinge Neil , Halker Raj , Agraharkar Mahendra 
Published: October 2004

AbstractSepsis is a common problem in patients who have cuffed catheters for hemodialysis. Line sepsis, however, has not often been associated with septic thrombophlebitis as seen in Lemierre syndrome. Thrombophlebitis of a central vein associated with catheter placement is extremely rare and when encountered is known to affect the femoral or the subclavian vein. Thrombophlebitis of the internal jugular vein after hemodialysis catheter placement has not been reported. We present the case of a woman with line sepsis who developed Lemierre syndrome, a serious complication of which the medical community should be aware. Lemierre syndrome requires a high index of suspicion for diagnosis and can have a fatal outcome if not treated with appropriate antibiotics.
A report on four new cases of nephrogenic fibrosing dermopathy in chronic hemodialysis patients
Authors: Sreenarasimhaiah Vijay P , Brown Wendy W , Cortese Cherize , Sirintrapun Joe , Janney Christine , Philipneri Marie , Gellens Mary , Flynn Lauren , Joseph Amy , Bastani Bahar 
Published: October 2004

AbstractNephrogenic fibrosing dermopathy (NFD) is a rare clinical entity affecting patients with renal failure, often on chronic dialysis or after transplantation. The patient profile at risk for this debilitating condition is undefined. Lack of awareness of the condition has hampered epidemiologic work in identifying the etiology. We present four chronic hemodialysis (HD) patients who developed this disease. The patients' ages ranged from 26 to 75 years, and they had received HD from between 20 months and 10 years before the diagnosis of NFD. Two patients had a history of renal transplantation. All patients had progressive thickening and woody induration of the skin associated with contractures, leading to difficult ambulation, and permanent disability within weeks of the diagnosis. In one case, the diaphragm, psoas muscle, and pericardium were involved. The latter is likely the first report of pericardial involvement of NFD. In all four patients, the skin findings were restricted to the extremities, sparing the trunk and face. Skin biopsy findings included thickened dermis with particularly thickened collagen bundles, fibroblast proliferation, minimal mucin deposition, and nearly absent inflammation. The pathologic findings were distinct from scleromyxedema and scleroderma. We found no laboratory evidence of autoimmune disease or thyroid dysfunction to account for alternate etiologies. CD34‐positive cells were documented in the skin biopsies as well as in the diaphragm, psoas muscle, and pericardial tissue of the concerned case. NFD is a novel fibrosing disorder of progressively debilitating nature which needs further clinical characterization and recognition to guide investigation of its pathogenesis.
Partial transformation of gabbro to coesite‐bearing eclogite from Yangkou, the Sulu terrane, eastern China
Authors: ZHANG R. Y. , LIOU J. G. 
Published: October 2004

An ultra‐high‐pressure (UHP) metamorphic slab at Yangkou Beach near Qingdao in the Sulu region of China consists of blocks of eclogite facies metagabbro, metagranitoid, ultramafic rock and mylonitic orthogneisses enclosed in granitic gneiss. A gradational sequence from incipiently metamorphosed gabbro to completely recrystallized coesite eclogite formed at ultra‐high‐pressures was identified in a single 30 m block; metagabbro is preserved in the core whereas coesite eclogite occurs along the block margins. The metagabbro contains an igneous assemblage of Pl+Aug+Opx+Qtz+Bt+Ilm/Ti‐Mag; it shows relict magmatic textures and reaction coronas. Fine‐grained garnet developed along boundaries between plagioclase and other phases; primary plagioclase broke down to Ab+Ky+Ms+Zo±Grt±Amp. Augite is rimmed by sodic augite or omphacite, whereas orthopyroxene is rimmed by a corona of Cum±Act and Omp+Qtz layers or only Omp+Qtz. In transitional rocks, augite and orthopyroxene are totally replaced by omphacite, and the lower‐pressure assemblage Ab+Ky+Phn+Zo+Grt coexists with domains of Omp (Jd70–73)+Ky±Phn in pseudomorphs after plagioclase. Both massive and weakly deformed coesite‐bearing eclogites contain Omp+Ky+Grt+Phn+Coe/Qtz+Rt, and preserve a faint gabbroic texture. Coesite inclusions in garnet and omphacite exhibit limited conversion to palisade quartz; some intergranular coesite and quartz pseudomorphs after coesite also occur. Assemblages of the coronal stage, transitional and UHP peak occurred at about 540±50 °C at c. 13 kbar, 600–800 °C at ≥15–25 kbar and 800–850 °C at >30 kbar, respectively.Garnet from the coronal‐ through the transitional‐ to the eclogite‐stage rocks show a decrease in almandine and an increase in grossular±pyrope components; garnet in low‐grade rocks contains higher MnO and lower pyrope components. The growth textures of garnet within pseudomorphs after plagioclase or along grain boundaries between plagioclase and other phases are complex; the application of garnet zoning to estimate P–T  should be carried out with caution. Some garnet enclosing quartz aggregates as inclusions shows radial growth boundaries; these quartz aggregates, as well as other primary and low‐P phases, persisted metastably at UHP conditions due to sluggish reactions resulting from the lack of fluid during prograde and retrograde P–T  evolution.
Thermobarometry of phengite‐bearing eclogites in the Dabie Mountains of central China
Authors: CARSWELL D. A. , O'BRIEN P. J. , WILSON R. N. , ZHAI M. 
Published: October 2004

Pressure–temperature conditions for formation of the peak metamorphic mineral assemblages in phengite‐bearing eclogites from Dabieshan have been assessed through a consideration of Fe2+–Mg2+ partitioning between garnet–omphacite and garnet–phengite pairs and of the reaction equilibrium celadonite+pyrope+grossular=muscovite+diopside, which incorporates an evaluation of the extent of the strongly pressure‐dependent inverse Tschermak's molecule substitution in the phengites. For the latter equilibrium, the calibration and recommended activity–composition models indicated by Waters & Martin (1993) have been employed and importantly yield results consistent with petrographic evidence for the stability at peak conditions of coesite in certain samples and quartz in others.Confirmation that in some phengite‐eclogite samples peak silicate mineral assemblages have equilibrated at confining pressures sufficient for the stability of coesite (and in some cases even diamond) rather negates previous suggestions that coesite may have been stabilized in only very localized, possibly just intracrystalline, domains. Inherent difficulties in the evaluation of peak metamorphic temperatures from Fe2+–Mg2+ partitioning between mineral phases, due to uncertainties over Fe3+/Fe2+ ratios in the minerals (especially omphacites), and to re‐equilibration during extensive retrograde overprinting in some samples, are also assessed and discussed.Our results indicate the existence in south‐central Dabieshan of phengite eclogites with markedly different equilibration conditions within two structurally distinct tectonometamorphic terranes. Thus our data do not support earlier contentions that south‐central Dabieshan comprises a structurally coherent continental‐crust terrane with a regional P–T  gradient signalling previous deepest‐level subduction in the north. Instead, we recognize the Central Dabie ultra‐high‐pressure (coesite eclogite‐bearing) terrane to be structurally overlain by a Southern Dabie high‐pressure (quartz eclogite‐bearing) terrane at a major southerly dipping shear zone along which late orogenic extensional collapse appears to have eliminated at least 20 km of crustal section.