bluuebunny/crossref_metadata_2025 huggingface dataset:
High Glucose Solution and Spent Dialysate Stimulate the Synthesis of Transforming Growth Factor-β1 of Human Peritoneal Mesothelial Cells: Effect of Cytokine Costimulation
Authors: Kang Duk-Hee , Hong Young-Sook , Lim Hyun Joung , Choi Jin-Hee , Han Dae-Suk , Yoon Kyun-Il
Published: February 2020

Objective

To investigate the effect of high glucose and spent peritoneal dialysate on the transforming growth factor-β1 (TGFβ1) synthesis of cultured human peritoneal mesothelial cells (HPMCs) and to examine the effect of costimulation with high glucose or spent dialysate, and cytokines, interleukin-1β (IL-1β), and tumor necrosis factor-α (TNFα) on TGFβ1 synthesis of HPMCs.

Design

HPMCs were exposed to different concentrations of glucose (30, 60, and 90 mmol/L) or spent peritoneal dialysate for 48 hours in the absence or presence of IL-1β (1 ng/mL) and TNFα (1 ng/mL). TGFβ1 mRNA expression was assessed by Northern blot analysis and TGFβ1 protein release by Western blot analysis and enzymelinked immunosorbent assay (ELISA).

Results

Exposure of HPMCs to high glucose conditions (30, 60, and 90 mmol/L of D-glucose) induced 2.3-, 3.6-, and 4.0-fold increases in TGFβ1 mRNA expression of HPMC with enhanced TGFβ1 protein synthesis and secretion into the media, whereas there were no significant changes in TGFβ1 synthesis with equimolar concentrations of D-mannitol. Incubation with spent dialysate also significantly increased TGFβ1 mRNA expression and protein secretion compared to control media ( p < 0.05). Stimulation with IL-1β (1 ng/mL) or TNFα (1 ng/mL) resulted in a significant increase in TGFβ1 mRNA expression after 48 hours: 2.7 and 2.1 times the control level, respectively. However, TNFα-induced increase in TGFβ1 mRNA expression was not translated into TGFβ1 protein secretion, while IL-1β stimulation induced a significant increase in TGFβ1 protein secretion as well as TGFβ1 mRNA expression. Combined stimulation by high glucose or spent dialysate, together with IL-1β or TNFα, showed a greater increase in TGFβ1 mRNA expression and protein secretion compared to stimulation by high glucose or spent dialysate alone.

Conclusion

Our results clearly show that high glucose solution and spent dialysate themselves might be sufficient to stimulate the production of TGFβ1 by peritoneal mesothelial cells. In peritoneal dialysis patients, this state of chronic induction of TGFβ1 is further exacerbated in the presence of peritonitis because of the stimulatory effect of proinflammatory cytokines, resulting in augmented TGFβ1 synthesis, thus promoting peritoneal fibrosis.
Calcium Use Increases Risk of Calciphylaxis: A Case-Control Study
Authors: Zacharias James M. , Fontaine Bunny , Fine Adrian
Published: February 2020

Objective

To investigate the risk factors for the development of calciphylaxis in renal failure, a poorly understood and often fatal condition characterized by calcium deposition in tissues.

Design

Retrospective case-control study.

Setting

University hospital peritoneal dialysis center.

Patients

Eight continuous ambulatory peritoneal dialysis (CAPD) patients with calciphylaxis were identified in a 3-year period. We matched up to five controls for dialysis modality and length of time on dialysis with each case.

Statistics

Multivariate conditional logistic regression analysis for matched case-controls.

Main Outcome Measures

Laboratory data and demographics were collected as well as cumulative calcium and vitamin D ingestion over the year prior to disease onset.

Results

All the patients were female, versus only 38% (14/37) of controls ( p < 0.0001). While not statistically significant, a majority of the patients were diabetic [62.5% (5/8) vs 32% (12/37)]. Peak and average levels of serum calcium, phosphate, calcium x phosphate product, parathyroid hormone (PTH), albumin, iron, total iron-binding capacity (TIBC), and ferritin were not significantly different in cases compared with controls. The use of calcitriol alone or with calcium carbonate was not found to be a significant risk factor for the development of calciphylaxis. In a multivariate analysis, iron intake seemed to be protective, contrary to previous reports, while the use of calcium carbonate was associated with a strong trend to increased risk of calciphylaxis development (odds ratio = 1.029/g and 1.011/g calcium ingested per month, at 1 and 2 – 3 months prior to calciphylaxis development; p = 0.0556 and 0.0565, respectively).

Conclusion

These data, although limited by the small numbers of index cases, suggest that calcium ingestion is a risk factor for calciphylaxis. The increased use of calcium salts as a phosphate binder in recent years might explain the apparent increased incidence of calciphylaxis in our and other centers. The preponderance of female diabetics among cases reported elsewhere was confirmed in our study.
A Comparative Analysis on the Incidence of Peritonitis and Exit-Site Infection in Capd and Automated Peritoneal Dialysis
Authors: Rodríguez–Carmona Ana , Fontán Miguel Pérez , Falcón Teresa García , Rivera Constantino Fernández , Valdés Francisco
Published: February 2020

Objective

To compare the incidence of peritonitis and exit-site infection in an ample group of patients undergoing continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis in a single center during a 10-year period.

Design

Nonrandomized, prospective study.

Setting

Public, tertiary care hospital providing peritoneal dialysis care to a population of (approximately) 750 000 people.

Patients

We studied 213 patients on CAPD and 115 on automated peritoneal dialysis (APD) starting therapy between January 1989 and August 1998, with a minimum follow-up of 3 months.

Main Outcome Measures

Using a multivariate approach, we compared the incidence, clinical course, and outcome of peritonitis and exit-site infections in both groups, controlling for other risk factors for the complications studied.

Results

The incidence of peritonitis was higher in CAPD than in APD (adjusted difference 0.20 episodes/ patient/year, 95% confidence interval 0.08 – 0.32). There was a trend for CAPD patients to present earlier with peritonitis than APD patients, yet the incidence of and survival to the first exit-site infection were similar in both groups. The etiologic spectrum of infections displayed minor differences between groups. Automated PD patients were more frequently hospitalized for peritonitis, but otherwise, the complications and outcome of peritonitis and exit-site infections did not differ significantly between patients on CAPD and those on APD.

Conclusions

Automated PD is associated with a lower incidence of peritonitis than is CAPD, while exit-site infection is similarly incident under both modes of therapy. The etiologic spectrum, complications, and outcome of peritonitis and exit-site infection do not differ markedly between CAPD and APD. Prevention of peritonitis should be included among the generic advantages of APD over CAPD.
Peritoneal Loss of Growth Hormone in Children on Automated Peritoneal Dialysis
Authors: Haffner Dieter , Hofstetter Christina , Mehls Otto , Schaefer Franz
Published: February 2020

Objective

To provide quantitative data regarding the daily dialytic loss of growth hormone (GH) in children on peritoneal dialysis (PD).

Design

Prospective study involving 24-hour dialysate collections on 3 consecutive days in patients with and without recombinant human GH (rhGH) treatment.

Setting

Single-center outpatient PD program.

Patients

Twenty-six children undergoing automated PD (APD): 6 with and 20 without daily rhGH.

Main Outcome Measures

Daily peritoneal losses of GH, α1-, β2-microglobulin, transferrin, and albumin.

Results

The mean (±SEM) daily dialytic GH loss was 2.18 ± 0.62 μg/1.73 m2 per day in rhGH-treated patients and 0.42 ± 0.28 μg/1.73 m2 per day in untreated patients, ( p < 0.05). The intraindividual coefficient of variation of daily GH loss was 65%. The peritoneal loss of GH was positively correlated with that of β2-microglobulin ( r = 0.77, p < 0.001) and α1-microglobulin ( r = 0.51, p < 0.01). The variability in β2-microglobulin and α1-microglobulin elimination, together with the use of rhGH, explained 66% of the total variability of daily GH excretion. In patients without rhGH therapy, the daily peritoneal GH loss was approximately 0.05% of the estimated daily endogenous production rate based on previous estimates in children with end-stage renal failure. In patients on rhGH therapy, less than 0.1% of the injected rhGH dose was eliminated by dialysis.

Conclusion

Peritoneal losses of GH in children on APD account only for a minute fraction of endogenous metabolic clearance, and do not explain the variability of the rhGH treatment response. The assessment of dialytic GH elimination may be used to estimate time-integrated mean plasma GH concentrations, and to monitor rhGH treatment compliance.
Measurement of Fluid Shift in Capd Patients Using Segmental Bioelectrical Impedance Analysis
Authors: Song Joon Ho , Lee Seoung Woo , Kim Gyeong A. , Kim Moon-Jae
Published: February 2020

Objective

To determine, using segmental bioelectrical impedance analysis (BIA), the characteristics of fluid shift of each body segment in continuous ambulatory peritoneal dialysis (CAPD) patients during and after peritoneal dialysis (PD) solution exchange.

Design

Observational study with repeated measurements of bioelectrical impedance, which is inversely related to tissue fluid content.

Patients

Thirteen clinically stable CAPD patients.

Methods

Bioelectrical impedance was measured at frequencies of 5, 50, 250, and 500 kHz in each body segment four times: (1) before and (2) after drainage of dialysate, and (3) at 1 hour and (4) at 2 hours after exchange of new 1.5% dextrose PD solution.

Results

Impedance of both arms was significantly increased at 1 hour post exchange at all frequencies. In the trunk, impedance at all frequencies increased significantly after drainage, decreased significantly at 1 hour post exchange, and then increased again for the next hour without significance. Impedance of both legs showed a decreasing tendency at all frequencies during and after exchange. Net calculated water volume changes between the time before drainage and 2 hours post exchange were –0.5 L in the trunk, –0.25 L in both arms, +0.47 L in both legs, –0.28 L in total. The change in body weight between the time before drainage and 2 hours post exchange was –0.21 kg, on average, and significantly correlated with total net calculated water volume change ( p = 0.009).

Conclusions

Each body segment of the CAPD patient has its own characteristic pattern of fluid shift in response to PD solution exchange or dwell. Segmental BIA may be a useful tool for understanding the physiological changes in fluid shift in CAPD patients.
Gastric Emptying and Electrogastrography in Patients on Capd
Authors: Fernström Anders , Hylander Britta , Grybäck Per , Jacobsson Hans , Hellström Per M.
Published: February 2020

Objective

To evaluate if impaired gastric emptying of digestible solids can explain the disturbed eating behavior in continuous ambulatory peritoneal dialysis (CAPD) patients, and if predialytic and dialytic (CAPD and hemodialysis) patients with impaired gastric emptying have a higher prevalence of electrogastrographic (EGG) abnormalities.

Design

Cross-sectional study. After ingestion of a 99mTc-labeled test meal, anterior and posterior 1-minute scintigraphic acquisitions were collected every 5 minutes during the first 50 minutes and thereafter every 10 minutes until 2 hours had elapsed. Simultaneously, cutaneous EGG recorded gastric myoelectric activity.

Setting

The Division of Nephrology and the Department of Nuclear Medicine at the same academic teaching hospital.

Participants

Thirty outpatients participated in both the gastric emptying and the EGG studies. Dialysis patients should have been on dialysis for more than 3 months. For comparison, 160 healthy control subjects participated in the gastric emptying study.

Main Outcome Measures

The following parameters were used to describe gastric emptying: lag phase 90%, half-emptying time ( T50), gastric retention at 90 and 120 minutes (Ret 90/120) and gastric emptying rate (GER, %/min). Electrogastrographic measurements were expressed as percentages of normal slow waves [2.4 – 3.6 cycles/min (cpm)], bradygastria (1.5 – 2.4 cpm), and tachygastria (3.6 – 10 cpm).

Results

T50 was prolonged, Ret 90 and Ret 120 were higher, and GER was slower in male CAPD patients compared to male controls. No significant differences were found in postprandial EGG.

Conclusion

Gastric emptying is impaired in male non-diabetic CAPD patients. However, abnormalities in postprandial EGG cannot explain this finding.
Peritoneal Transport of Glucose in Rat
Authors: Park Min Sun , Lee Eun Young , Suh Gyo Il , Waniewski Jacek , Werynski Andrzej , Lee Hi Bahl
Published: February 2020

Objective

To evaluate the convective transport characteristics of glucose and the effect of high glucose and insulin during experimental peritoneal dialysis in rat.

Methods

Male Sprague–Dawley rats weighing 300 – 400 g were used in this study. Mannitol (5%) was used as osmotic agent. Glucose was added to dialysis solution to yield a concentration of 100 mg/dL (group 1) or 300 mg/dL (group 2). Mannitol solution (5%) containing the same concentration of electrolytes and lactate but without glucose was used as control (group 3). In group 2, blood sugar was maintained at approximately 300 mg/dL by continuous intravenous infusion of 25% glucose solution and 0.9% NaCl solution. A 2-hour dwell study was performed with 30 mL of test solutions. Intraperitoneal volume was calculated by volume marker (18.5 kBq of 131I-human radioiodinated serum albumin, RISA) dilution with corrections made for the elimination of RISA from the peritoneal cavity (KE) and sample volume. The diffusive mass transport coefficient (KBD) and sieving coefficient (SBRF) were calculated by using the Babb–Randerson–Farrell model. S was also calculated directly by using isocratic methods (SI). The peritoneal fluid absorption rate (KE) was taken into account for the calculation of SI.

Results

Intraperitoneal volume was significantly higher in group 2 compared with groups 1 and 3. Peritoneal fluid absorption rate, KE, was similar in all three groups. SBRF and SI for glucose were significantly lower in group 2 compared with groups 1 and 3. SBRF for glucose in group 2 was below zero and SI near zero. KBD for glucose was significantly higher in group 2 than in groups 1 and 3. Plasma and dialysate concentrations of insulin increased during the initial hour and then decreased to the baseline value in groups 1 and 3, while in group 2 it continuously increased.

Conclusion

Significantly lower sieving coefficients for glucose in the high glucose and high insulin group suggest that transport mechanisms other than simple passive transport are involved in peritoneal glucose transport, and that high glucose per se and/or high insulin may be important factors that determine glucose transport characteristics.
Small and Middle Molecular Weight Solute Clearance in Nocturnal Intermittent Peritoneal Dialysis
Authors: Brophy Donald F. , Sowinski Kevin M. , Kraus Michael A. , Moe Sharon M. , Klaunig James E. , Mueller Bruce A.
Published: February 2020

Objectives

To determine the dialysate-to-plasma (D/P) concentration ratios and peritoneal dialytic clearance (ClD) of substances with a wide range of molecular weights in subjects receiving a simulated nocturnal intermittent peritoneal dialysis (NIPD) session.

Design

Open-label single-dose study.

Subjects

Six end-stage renal disease patients undergoing peritoneal dialysis (PD).

Setting

Clinical research center of a university-affiliated hospital.

Interventions

Subjects received intravenous gentamicin and vancomycin on the first day of the study. Subjects received no PD until their return on the following day, when subjects underwent a simulated NIPD session utilizing four 2- to 2.5-L peritoneal dialysate dwells of 2 hours. Blood and dialysate samples were collected immediately before the session and after each dialysate dwell for determination of urea, creatinine, gentamicin, vancomycin, and β2-microglobulin (β2M) concentrations. Each solute's D/P concentration ratio and peritoneal ClD were calculated.

Measurements and Main Results

The (mean ±SD) 2-hour D/P concentration ratios were 0.78 ± 0.05 (urea), 0.49 ± 0.11 (creatinine), 0.38 ± 0.08 (gentamicin), 0.11 ± 0.06 (vancomycin), and 0.07 ± 0.03 (β2M). Peritoneal ClD values (mL/min of dialysis) were 19.0 ± 2.8 (urea), 12.1 ± 3.5 (creatinine), 8.4 ± 2.8 (gentamicin), 2.7 ± 1.5 (vancomycin), and 1.7 ± 0.8 (β2M). The D/P concentration ratios and peritoneal ClD values for urea, creatinine, and gentamicin were significantly different from vancomycin and β2M (repeated measures ANOVA, p < 0.05). β2-Micro-globulin peritoneal ClD was strongly related to gentamicin peritoneal ClD ( r = 0.96, p < 0.05).

Conclusion

Small molecular weight solutes have significantly greater D/P and peritoneal ClD than middle molecular weight solutes in NIPD. In NIPD, daily peritoneal ClD of β2M is lower than that reported in continuous ambulatory PD. NIPD also results in lower drug ClD than that reported in continuous ambulatory PD studies.
The Self-Locating Catheter: Clinical Evaluation and Comparison with the Tenckhoff Catheter
Authors: Cavagna Romano , Tessarin Cristina , Tarroni Giovanni , Casol Daniela , De Silvestro Linda , Fabbian Fabio
Published: February 2020

Background

Peritoneal catheter displacement appears to be related to various causes including omental attachment, bowel contractions, peritoneal adhesions, and the catheter floating in the dialysis fluid. In order to prevent this complication, which can impair peritoneal dialysis efficacy, Di Paolo et al. designed a “self-locating catheter” (SLC) that is similar to the Tenckhoff catheter (TC) and includes a small tungsten cylinder (weight 12 g) at the distal end (Di Paolo N, et al. The self positioning catheter. Proceedings of the VII Italian Congress on Peritoneal Dialysis. Milan: Wichtig Editore, 1993:539–42). The weight of the tip prevents the catheter from floating and migrating by gravitation toward the Douglas cavity.

Objective

Starting in 1996, we implanted SLC in 15 continuous ambulatory peritoneal dialysis patients. The aim of our study was to compare the ratio of migration and other catheter-related complications between patients with SLC (196 patient-months) and 13 patients with conventional straight TC (295 patient-months).

Results

Peritonitis ratio, catheter complication rate, dialysate inflow and outflow, and weekly creatinine clearance were similar in the two groups of patients. The incidence of catheter displacement was significantly higher ( p = 0.0349) in the TC group than in the SLC group (4 vs 0).

Conclusion

In our experience, the SLC seems to be useful in preventing catheter migration by continuous gravitation of its extremity toward the pelvic cavity.
Alterations in Water and Solute Transport with Time on Peritoneal Dialysis
Authors: Heimbürger Olof , Wang Tao , Lindholm Bengt
Published: February 2020

Peritoneal ultrafiltration capacity and small -solute transport characteristics seem to be relatively stable in most patients treated with PD for up to 3 years. However, in patients treated with PD for 4 years or more, there is a tendency towards increasing diffusive transport for small solutes as well as a tendency towards decreasing net UF, whereas the peritoneal protein clearances seem to be reduced or stable.

Loss of UFC is a well-known complication during long-term PD treatment, and the risk for loss of UFC may be as high as 50% after 6 years on PD. Several different mechanisms of UFC loss have been reported. In particular, the most common mechanism for loss of UFC is increased diffusive transport resulting in rapid glucose absorption and thus rapid loss of the osmotic driving force. Also reported as causes of UFC loss have been: reduced efficiency of the osmotic agent (perhaps owing to decreased transcellular water transport); loss of peritoneal surface area with slow solute transport owing to fibrosis and the formation of adhesions (during the late stage of sclerosing peritonitis); and increased peritoneal fluid absorption. In individual patients, a combination of several mechanisms may be involved in the apparent UFC failure.
Intraperitoneal Addition of Hyaluronan Improves Peritoneal Dialysis Efficiency
Authors: Wang Tao , Cheng Hui-Hong , Heimbürger Olof , Chen Chi , Waniewski Jacek , Bergström Jonas , Lindholm Bengt
Published: February 2020

Background

It has been shown that hyaluronan (HA) can decrease peritoneal fluid absorption. It is not known, however, how various molecular weights and various concentrations of hyaluronan affect peritoneal fluid absorption rate.

Methods

A study of 4-hour dwells, with frequent dialysate and blood sampling, was performed in male SpragueCawley rats (6 7 rats in each group) with 1311 albumin as an intraperitoneal volume marker. Each rat was infused intraperitoneally with 25 mL of 1.5% glucose solution alone or 1.5% glucose solution containing hyaluronan at various molecular weights (MW -85 kC, 280 kC, 500 kC, and 4 MC) or containing hyaluronan of MW 500 kC at various concentrations (0.01%,0.05%,0.1%,0.5%). Two additional groups were infused with 40 mL of 1.36% glucose dialysate alone or 1.36% glucose dialysate with 0.01 % hyaluronan (MW 500 kC) to test the effect of hyaluronan when high dialysate fill volume was used.

Results

Addition of 0.01% hyaluronan significantly decreased peritoneal fluid absorption rate (KE) (by 22%, p < 0.01). The decrease was more marked with hyaluronan at high MW or high concentration, or with high dialysate fill volume. The net ultrafiltration tended to be higher in all hyaluronan groups compared to their control groups except in the 4 MC group; this difference was mainly due to a lower KE in all the hyaluronan groups. The direct lymphatic flow was significantly decreased in the 0.5% HA group. The transcapillary ultrafiltration rate (au) was significantly lower in the 4 MC group as compared to the control group. No difference in au was found between the other groups as compared to their control groups.

Conclusions

(1) Intraperitoneal addition of hyaluronan may increase net peritoneal fluid removal, mainly because hyaluronan decreases peritoneal fluid absorption rate. The decrease was more marked when high dialysate fill volume was used, indicating that intraperitoneal addition of hyaluronan can prevent the decreased net ultrafiltration caused by an increase in dialysate fill volume. (2) The decrease in peritoneal fluid absorption rate may be both MW-dependent and concentration-dependent: that is, a higher MW as well as a higher concentration of hyaluronan result in a more marked decrease in peritoneal fluid absorption rate. (3) Low concentrations of high MW hyaluronan may also decrease au. However, au did not decrease when high concentrations of hyaluronan were used despite a significant decrease in peritoneal fluid absorption rate.
Hypertension in Continuous Ambulatory Peritoneal Dialysis Patients: What do we know and What can we do about It?
Authors: Cheigh Jhoong S. , Kim Hyang
Published: February 2020

Despite many advantages of CAPD in maintaining hemodynamic stability, approximately 50% -60% of CAPD patients have hypertension and require antihypertensive treatment. ACE inhibitors and betablockers are the preferred first-line antihypertensive drugs in these patients, but some patients may require additionallong-acting calcium antagonists to enhance antihypertensive effects. Despite antihypertensive treatment, many patients often fail to maintain BP within optimal ranges, and this fact may contribute to the high incidences of cardiovascular morbidity an d mortality. Vigilance is clearly desirable by the patient and the physician to maintain BP within target ranges most of the time. Because dialysis patients also have many other cardiovascular risk factors, the strategy to decrease cardiovascular mortality should be a combined effort targeting all potential risk factors at the same time.
Effects of Recombinant Human Erythropoietin on Functional and Injury Endothelial Markers in Peritoneal Dialysis Patients
Authors: Aguilera Abelardo , Selgas Rafael , Ruiz-Caravaca M. Luisa , Bajo M. Auxiliadora , Cuesta M. Vicenta , Plaza M. Angeles , Hernanz Angel
Published: February 2020

Clinical effects of recombinant human erythropoietin (rHuEPO) such as thrombosis, convulsions, hyperviscosity, hypertension, and angiogenic effect in culture cells have been described. We studied the rHuEPO effect on endothelial damage markers and endothelial function markers: tissue-type plasminogen activator (t-PA), nitrate (NO3), thrombomodulin (TM), and von Willebrand factor (vWF). Twenty-six peritoneal dialysis patients treated with rHuEPO and 19 controls were included.

The study design for rHuEPO patients consisted of four periods: long-term treatment (rHuEPO-1); 2 months of withdrawal (rHuEPO-2); and 4 months on 5000 IU/week rHuEPO subcutaneously, with markers being measured after 2 months (rHuEPO-3) and after 4 months (rHuEPO-4).

After 2 months of rHuEPO withdrawal, a decrease in hemoglobin level appeared (11 ± 1.8 g/dL to 9.2 ± 1.5 g/dL, p < 0.01). After rHuEPO reintroduction, this value reached 10.6 ± 1.5 g/dL at two months, and 11.1 ± 1.4 g/dL at four months. A significant increase in t-PA ratio was observed from two months without rHuEPO to two months on rHuEPO, returning to previous values after four months. Similarly, TM increased for patients with creatinine clearances (CrC) < 5 mL/min. No changes in the higher-thannormal plasma vWF levels were found during the various periods. A statistically significant lower value was found in controls compared with rHuEPO-4 patients. A statistically significant increase in NO3 levels was observed in the pre-venous occlusion (VO) test immediately after the re-introduction of rHuEPO. This increment returned to prior values four months after rHuEPO was reintroduced.

Our results show that rHuEPO treatment causes an increase in some endothelial damage markers (TM, t-PA) and modifies endothelial function markers (t-PA ratio, NO3). These changes might favor thrombosis and atherosclerosis.
The Effect of Continuous Ambulatory Peritoneal Dialysis on Change in Serum Leptin
Authors: Kim Dae Joong , Oh Dong Jin , Kim Bum , Lim Young Hee , Kang Woo-Heon , Lee Bang Hoon , Lee Sung Ku , Huh Wooseong , Kim Sang Eun , Lee Moon-Kyu , Kang Soon Ah , Oh Ha-Young
Published: February 2020

Objective

Elevated serum leptin can contribute to anorexia and poor nutrition in patients with chronic renal failure, because leptin is elevated in chronic renal failure patients with or without dialysis, especially in chronic ambulatory peritoneal dialysis (CAPO) patients. The aim of this study was to find whether leptin can be removed by peritoneal dialysis (PO) and to analyze factors that can affect serum leptin after start of CAPO by observing the change in serum leptin shortly after start of CAPO and its correlation with body mass index (BMI), with serum insulin, and with residual renal function.

Design

Twenty patients who started CAPO during the observation period were studied. Serum leptin was measured by radioimmunoassay before start of CAPO, 3 5 days after start of CAPO, and 1 month and 3 months after start of CAPO. Simultaneously, body weight, serum insulin, and residual renal function were measured. To compensate for the circardian rhythm of leptin, removal of leptin was assessed by measuring dialysate leptin divided by average serum leptin before and after a peritoneal equilibration test (PET).

Results

Leptin was eliminated by PO with a dialysateto-serum ratio of 0.16 ± 0.07, which was comparable to removal of β2-microglobulin (0.14 ± 0.06). The mean serum leptin concentrations did not decrease after 3 5 days of CAPO (8.4 ± 13.1 ng/mL → 11.9 ± 18.0 ng/mL) despite its removal by PO, and levels increased markedly to 189% of basal serum leptin 1 month after start of PO and to 260% of basal serum leptin 3 months after start of PO. Correlation coefficients (Spearman's p) between change of serum leptin and change of BMI, of serum insulin, of glomerular filtration rate (average of urine creatinine clearance and urine urea clearance) were 0.267 (p > 0.05, n = 20),0.441 (p > 0.05, n = 16),0.706 (p > 0.05, n = 8) respectively.

Conclusion

Leptin is removed by peritoneal dialysis. Serum leptin did not decrease in 5 days after the start of PO despite its removal by PO, but increased markedly thereafter, within 3 months after start of PO. We could not find a significant correlation between the change in leptin and the change in BMI. Factors other than fat-mass gain can stimulate leptin increase shortly after start of PO.
Mathematical Models for Peritoneal Transport Characteristics
Authors: Waniewski Jacek
Published: February 2020

Four mathematical models and for the description of peritoneal transport of fluid solutes are reviewed. The membrane model is usually applied for (1) separation of transport components, (2) formulation of the relationship between flow components and their driving forces, and (3) estimation of transport parameters. The three-pore model provides correct relationships between various transport parameters and demonstrates that the peritoneal membrane should be considered heteroporous. The extended threepore model discriminates between heteroporous capillary wall and tissue layer, which are assumed to be arranged in series; the model improves and modifies the results of the three-pore model. The distributed model includes all parameters involved in peritoneal transport and takes into account the real structure of the tissue with capillaries distributed at various distances from the surface of the tissue.

How the distributed model may be applied for the evaluation of the possible impact of perfusion rate on peritoneal transport, as recently discussed for clinical and experimental studies, is demonstrated. The distributed model should provide theoretical bases for the application of other models as approximate and simplified descriptions of peritoneal transport. However, an unsolved problem is the theoretical description of bi-directional fluid transport, which includes ultrafiltration to the peritoneal cavity owing to the osmotic pressure of dialysis fluid and absorption out of the peritoneal cavity owing to hydrostatic pressure.
A Simple and Fast Method to Estimate Peritoneal Membrane Transport Characteristics Using Dialysate Sodium Concentration
Authors: Wang Tao , Waniewski Jacek , Heimbürger Olof , Bergstrβm Jonas , Werynski Andrzej , Lindholm Bengt
Published: February 2020

Background

The peritoneal equilibration test (PET) is widely used to classify a patient's peritoneal transport characteristics. However, PET is laborious and the prediction of fluid removal based on PET is generally poor. It is believed that osmosis by glucose occurs partially through transcellular water channels, resulting in sieving of sodium and decrease of dialysate sodium concentration when using hypertonic glucose dialysate.

Objective

In this study, we investigated the possibility of using dialysate sodium concentration to classify the patient's peritoneal transport characteristics.

Methods

A 6-hour dwell study with frequent dialysate and plasma sampling was performed in 46 patients using 2 L of 3.86% glucose dialysate with 1311-albumin as an intraperitoneal volume (IPV) marker. The peritoneal transport of sodium, creatinine, glucose, and fluid was evaluated.

Results

The dialysate sodium concentration at 240 min (ONa240) significantly correlated with O/P creatinine (r = 0.76, p < 0.001) and O/O0 glucose (r = -0.83, p < 0.001) at 240 min of the dwell (better than dialysate sodium concentration at any other time of the dwell). ONa240 also significantly correlated with IPV at 240 min of the dwell (r = -0.61, p < 0.001) (better than O/P creatinine and O/O0 glucose). There were significant correlations between ONa240 and the sodium-sieving coefficient (r= 0.71, p < 0.001) and the diffusive mass transfer coefficient for sodium (r = 0.50, p < 0.001). When using ONa240 to divide the patients into four groups, as in the PET method, no significant difference was found between the two methods.

Conclusion

Using 3.86% glucose solution, ONa240 can be used instead of O/P creatinine to classify patients into different transport groups. ONa240 provides a better prediction of peritoneal fluid transport and reflects both the diffusive and convective transport properties of the membrane. As only one dialysate sample (and no blood sample) is needed, ONa240 may offer important clinical advantages compared with PET.
The Role of Protein Kinase C Activation in the Pathogenesis of Diabetic Vascular Complications
Authors: Park Joong Yeol , Ha Sung-Woo , King George L.
Published: February 2020

Many vascular diseases in diabetes are known to be associated with the activation of the diacylglycerol (OAG)protein kinase C (PKC) pathway. The major source of OAG that is elevated in diabetes is de novo synthesis from glycolytic intermediates. Among the various PKC isoforms, the β-isoform has been shown to be persistently activated in diabetic animals. Multiple lines of evidence have shown that many vascular alterations in diabetes such as a decrease in the activity of Na+-K+ -adenosine triphosphatase (Na+-K+-ATPase), and increases in extracellular matrix, cytokines, permeability, contractility, and cell proliferation -are caused by activation of PKC. Inhibition of PKC by two different kinds of PKC inhibitors, LY333531, a selective PKC-β-isoform inhibitor, and d-α-tocopherol, were able to prevent or reverse the various vascular dysfunctions in diabetic rats. These results have also provided in vivo evidence that OAG-PKC activation could be responsible for the hyperglycemia-induced vascular dysfunctions in diabetes. Clinical studies are now being performed to clarify the pathogenic roles of the OAG-PKC pathway in developing vascular complications in diabetic patients.
Taste Buds and Neuronal Markers in Patients with Chronic Renal Failure
Authors: Astbäck Johnny , FernstrÖm Anders , Hylander Britta , Arvidson Kristina , Johansson Olle
Published: February 2020

Objective

To study the number of taste buds and, with the use of specific markers for peripheral nervous tissue, to study the neuronal pattern in taste buds from 36 patients with chronic renal failure (CRF), 19 renal transplant recipients, and 40 healthy subjects. Of the patients with CRF, 17 patients had not started dialysis, 12 patients were on peritoneal dialysis, and 7 patients were on hemodialysis.

Design

From all subjects, two or three fungiform papillae were collected from the anterior part of the tongue. Cryostat sections were cut and inspected under light microscopy to determine the presence of taste buds. The sections were subsequently incubated with primary rabbit antibodies against protein gene product 9.5, substance P, and nerve growth factor receptor.

Results

Using these antibodies, no differences between the groups were observed. However, patients with CRF had fewer taste buds than control subjects.

Conclusion

No immunohistochemical differences were observed between patients with CRF and healthy controls. However, patients with CRF had significantly fewer fungiform taste buds, suggesting an important factor contributing to the well-known impairment of taste acuity in this patient group.
Renal Osteodystrophy in Pre-Dialysis Patients: Ethnic Difference?
Authors: Shin Sug Kyun , Kim Do Hun , Kim Heung Su , Shin Kyu Tae , Ma Kyung Ae , Kim Sung Jung , Kwak Youn Sik , Ha Seung Kyu , Sherrard Donald J.
Published: February 2020

The purpose of the present study is to investigate whether an ethnic difference exists in the incidence of renal osteodystrophy between Asian and Western countries in end-stage renal disease (ESRD) patients. We evaluated bone histology in 58 pre-dialysis patients (28 male, 30 female; mean age: 47.7 years). All patients had bone biopsies with quantitative histomorphometry and sero-logical parameters such as intact PTH, osteocalcin, total alkaline phosphatase, and basal and deferoxamine-stimulated serum aluminum levels.

We observed that 91.4% of all evaluated patients showed renal osteodystrophy before the start of dialytic therapy. Mild osteitis fibrosa were observed in 21 patients (36.2%), severe osteitis fibrosa in 5 patients (8.6%), mixed lesions in 7 patients (12.1 %), osteomalacia in 6 patients (10.3%), aplastic bone disease in 14 patients (24.1%), and normal bone in 5 patients (8.6%). Among the bone histomorphometric parameters, fibrosis area rate (%) showed the best correlation with intact PTH, and osteocalcin and osteoid area rate (%) with total alkaline phosphatase. Aluminum-related bone disease was not observed. Among patients with aplastic bone disease, only 14.3% showed aluminum deposition of any significance (5% < stainable bone surface aluminum < 25%). In the diabetic patients, aplastic bone disease was most common, but no case was related to aluminum intoxication.

In conclusion, the distribution of renal osteodystrophy in our study was different from that of Western countries in pre-dialysis patients. Our patients tended to have more mild-form osteitis fibrosa and normal findings, and less severe-form osteitis fibrosa and aplastic bone disease. Aluminum-related bone disease was not observed.
β2-Microglobulin and Renal Bone Disease
Authors: Wada Takehiko , Miyata Toshio , Sakai Hideto , Kurokawa Kiyoshi
Published: February 2020

Dialysis-related amyloidosis (DRA) is characterized by amyloid deposition mainly in bone and joint structures, presenting as carpal tunnel syndrome, destructive arthropathy, and subchondral bone erosions and cysts. β2-microglobulin has been demonstrated to be a major constituent of amyloid fibrils. DRA occurs not only in patients undergoing long-term hemodialysis, but also in patients undergoing continuous ambulatory peritoneal dialysis. The incidence of this complication increases with the duration of dialytic therapy and the age of the patient. While a definitive diagnosis of DRA can be made only by histological findings, various imaging techniques often support diagnosis. The molecular pathogenesis of this complication remains unknown. Recent studies have, however, suggested a pathogenic role of a new modification of β2-microglobulin in amyloid fibrils -that is, the advanced glycation end-products (AGEs) formed with carbonyl compounds derived from autoxidation of both carbohydrates and lipids (“carbonyl stress”). Therapy for DRA is limited to symptomatic approaches and surgical removal of amyloid deposits. High-flux biocompatible dialysis membranes could be used to delay DRA development.
Long Term Experience with Growth Hormone Treatment in Children with Chronic Renal Failure
Authors: Schaefer Franz , Haffner Dieter , Wühl Elke , Mehls Otto
Published: February 2020

After a decade of experience with recombinant human growth hormone (rhGH) in children with chronic renal failure (CRF), the long-term efficacy and safety of the drug is now established. In prepubertal children, partial catch-up growth is achieved during the first three treatment years, followed by sustained percentile-parallel growth. Discontinuation of rhGH treatment results in catch-down growth in 75% of patients. Treatment efficacy is inversely correlated with age and baseline height velocity, and positively influenced by genetic target height and residual renal function. Skeletal maturation is not accelerated, suggesting a true increase in final height potential. Side effects are limited to a stimulation of insulin secretion, which is not associated with changes in glucose tolerance, and occasional cases of benign intracranial hypertension.

In summary, the advent of rhGH has opened a new era in the management of growth failure in CRF. Available evidence suggests that treatment should start in early childhood and early in the course of renal failure, and should be continued at least until renal transplantation. It remains to be seen whether the beneficial effect of rhGH on height observed during the prepubertal period will result in an eventual increase in adult height.
Pediatric Peritoneal Dialysis in Korea: Practical Solutions to the Problems of Peritoneal Dialysis for Children
Authors: Kim Pyung-Kil , Kim Ji-Hong
Published: February 2020

Purpose

To find and solve the common problems of peritoneal dialysis (PD) by analyzing the clinical data of pediatric PD performed in Korea.

Methods

We looked at 264 cases of continuous ambulatory peritoneal dialysis (CAPD) and acute PD that were performed in 18 institutions of pediatric nephrology in Korea from November 1987 to October 1997.

Results

CAPD was performed in 114 cases. The mean age of the patients was 10.5 ± 6.6 years, and the male-to female ratio was 1.4:1. The original causes of end-stage renal disease (ESRD) were proven in 92 cases (81%). The most common renal diseases were focal segmental glomerulosclerosis (17%), reflux nephropathy (11%), and chronic glomerulonephritis (11 %). Mean duration of CAPD was 20 months ± 16.9 months. Peritonitis was the most common complication, and the peritonitis incidence was 0.96 episode per patient-year. Other complications were exit-site infection in 10 cases, obstruction in 7 cases, and leakage of dialysate in 6 cases. The most common etiologic organism of peritonitis was Staphylococcus aureus and the next most common was coagulase-negative staphylococcus. Acute PD was performed in 150 cases. The most common underlying causes were congenital heart disease, hemolytic uremic syndrome, sepsis, and dehydration. The mean duration was 10.3 ± 11.3 days. The most common complication was peritonitis (78.3%). The most common etiologic organisms of peritonitis were Staphylococcus aureus, coag-neg staphylococcus, Acinetobacter, and Pseudomonas.

Conclusion

Reflux nephropathy should be emphasized in early diagnosis and treatment to prevent ESRD. Incidence of congenital anomaly (7%) as a original cause of ESRD was relatively low in Korea. Growth status was not significantly improved after CAPD. In acute PD, the incidence of peritonitis rapidly increased at 2 weeks after the start of dialysis.
Taking Peritoneal Dialysis beyond the Year 2000
Authors: Gokal Ram
Published: February 2020

Over the past 25 years, peritoneal dialysis (PD) has steadily improved so that now its outcomes, in the form of patient survival, are equivalent to, and at times better than, those for hemodialysis. We now have a better understanding of the pathophysiology of peritoneal membrane function and damage and the importance of appropriate prescription to meet agreed-upon targets of solute and fluid removal. In the next millennium, greater emphasis will be put on prescription setting and subsequent monitoring. This will entail an increase in automated PD, especially for lifestyle reasons as well as for patients with a hyperpermeable peritoneal membrane.

To improve outcomes, dialysis should be started earlier than is currently the case. It is easy to do this with PD, where an incremental approach is made easier by the introduction of icodextrin for long-dwell PD. In the future, solutions will be tailored to be more biocompatible and to provide improved nutrition and better cardiovascular outcomes.

Finally, economic considerations favor PD, which is cheaper than in-centre hemodialysis. Thus, for many, PD has become a first-choice therapy, and with further improvements this trend will continue.
The compressive behavior of a composite cylindrical pyramidal lattice structure manufactured with a new production methodology
Authors: Mohammadi Masoud , Sadeghi Ali
Published: February 2020

In this paper, a new manufacturing method of pyramidal lattice cells has been suggested to produce lattice composite cylinders. Moreover, the effect of fiber volume fraction, vacuum molding, and fiber pre-tension has been investigated on the load-carrying capacity of the cylindrical pyramidal lattice structure of a carbon fiber composite. The carbon fiber composite cylindrical pyramidal lattice structure has been manufactured with laying fibers along the grooves of a silicone mold. Then, it has been subjected to the axial compressive test. Furthermore, to make pre-tension in fibers, a metal mold has been designed. Fiber pre-tension ensures the alignment of the fibers is straight between two nodal points. Additionally, the structure has been analyzed by the finite element buckling procedure. Experimental tests on the structures show that using a metal mold compare to the silicone molding method increases load-carrying capacity up to 48% without significantly varying the weight. Therefore, this method can be used for manufacturing pyramidal lattice structures in the hand layup process.
Persistent Chlamydia trachomatis, Neisseria gonorrhoeae or Trichomonas vaginalis positivity after treatment among human immunodeficiency virus-infected pregnant women, South Africa
Authors: Medina-Marino Andrew , Mudau Maanda , Kojima Noah , Peters Remco PH , Feucht Ute D , Vos Lindsey De , Olivier Dawie , Muzny Christina A , McIntyre James A , Klausner Jeffrey D
Published: February 2020

The objective of this study is to assess the predictors and frequency of persistent sexually transmitted infection (STI) positivity in human immunodeficiency virus (HIV)-infected pregnant women treated for Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) or Trichomonas vaginalis (TV) infection. We enrolled HIV-infected pregnant women attending their first antenatal care visit and tested them for urogenital CT, NG and TV infection using Xpert® CT/NG and TV assays (Cepheid, Sunnyvale, CA). Those testing positive were treated. Participants either notified partners to seek treatment or were given extra medication to deliver to partners for treatment. Repeat testing was conducted approximately 21 days post-treatment or treatment initiation. Among 427 participants, 172 (40.3%) tested positive for any STI. Of the 136 (79.1%) that returned for repeat testing, 36 (26.5%) tested positive for the same organism: CT = 27 (26.5%), NG = 1 (6.3%), TV = 11 (16.7%). Persistent CT positivity was independently associated with having more than one sex partner in the preceding 12 months (adjusted-prevalence ratio [aPR] = 3.03, 95% CI: 1.44–6.37) and being newly diagnosed with HIV infection during the first antenatal care visit compared to those currently on antiretroviral therapy (aPR = 3.97, 95% CI: 1.09–14.43). Persistent TV positivity was associated with not knowing if a partner sought treatment following STI disclosure (aPR = 12.6, 95% CI: 2.16–73.5) and prior diagnosis of HIV but not currently on antiretroviral therapy. (aPR = 4.14; 95% CI: 1.25–13.79). We identified a high proportion of HIV-infected pregnant women with persistent CT or TV positivity after treatment. To decrease the risk of re-infection, enhanced strategies for partner treatment programmes are needed to improve the effectiveness of STI screening and treatment in pregnancy. The relationship between not being on antiretroviral therapy and persistent STI positivity needs further study.