Urobiome: In Sickness and in Health.

The human microbiome has been proven to contribute to the human condition, both in health and in disease. The metagenomic approach based on next-generation sequencing has challenged the dogma of urine sterility. The human urobiome consists of bacteria and eukaryotic viruses as well as bacteriophages, which potentially represent the key factor. There have been several significant findings with respect to the urobiome in the context of urological disorders. Still, the research on the urobiome in chronic kidney disease and kidney transplantation remains underrepresented, as does research on the role of the virome in the urinary microbiota. In this review, we present recent findings on the urobiome with a particular emphasis on chronic kidney disease and post-kidney transplantation status. Challenges and opportunities arising from the research on the human urobiome will also be discussed.

Biocompatibility of synthetic ultraviolet radiation cross-linked polymers - Subcutaneous implantation study.

Photo-cross-linked polymers have attracted a lot of attention in the biomedical field. The main benefits of these materials are related to the fact that they are most of the time viscous liquids or pastes that adapt a custom and fixed shape on demand of the user. Present study deals specifically with the biological response upon subcutaneous implantation of four different materials in rabbits. In the study 20 rabbits were divided into four groups (each five rabbits): Groups 1-3 were implanted with tested new obtained by us macromonomers (P1838-DMA; P1838-UR; PDEGA-UR - respectively), while group 4 (control) was implanted with the mesh (PLA) routinely used for surgical treatment of a hernia. The new compounds were polarized earlier using ultraviolet radiation to obtain cross-linked networks. The polymers in the form of discs were then implanted subcutaneously in dorsal region of rabbits. After 28 days polymers were explanted and examined. Microscopic observation evaluated: thickness of the connective tissue capsule around the discs, cells of inflammatory response, disc surface erosion, spectroscopic analysis. The examined materials cause no chronic inflammation, abscesses or tissue necrosis, and the biological response is similar to observed in control group. Therefore, new synthetic materials could be considered as biocompatible and safe. Materials undergo slow degradation of ester bonds and surface erosion and degradation products could be eliminated probably by phagocytosis. On the basis on the afore mentioned knowledge, we formulated hypothesis, that the new polymers are well tolerated by the adjacent tissues. The aim of the following study was to examine reaction of the tissue on new types of prepolymerized material implanted subcutaneously. The obtained results suggest, that the new UV cross-linked polymers do not affect negatively on the connective tissue that is in the contact with the implants. Furthermore, the used materials are in the liquid form, thus they could be easily performed in in minimally invasive laparoscopic treatment of abdominal hernias. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1889-1897, 2019.

Clinical and Biochemical Characteristics of Brain-Dead Donors as Predictors of Early- and Long-Term Renal Function After Transplant.

OBJECTIVES: Organs from brain-dead donors are the main source of allografts for transplant. Comparisons between living-donor and brain-dead donor kidneys show that the latter are more likely to demonstrate delayed graft function and lower long-term survival. This study aimed to assess the effects of various clinical and biochemical factors of donors on early- and long-term renal function after transplant. MATERIALS AND METHODS: We analyzed data from kidney recipients treated between 2006 and 2008 who received organs from brain-dead donors. Data from 54 donors and 89 recipients were analyzed. RESULTS: No relation was observed between donor sodium concentration and the presence of delayed graft function. Donor height was positively correlated with creatinine clearance in recipients in the 1 to 3 months after renal transplant. Donor diastolic blood pressure was negatively correlated with estimated glomerular filtration rate throughout the observation period. Donor age was negatively correlated with the allograft recipient's estimated glomerular filtration rate throughout 4 years of observation. Donor estimated glomerular filtration rate was positively correlated with that of the recipient throughout 3 years of observation. CONCLUSIONS: The results of this study indicate that various factors associated with allograft donors may influence graft function.

Birth defects in juvenile Wistar rats after exposure to immunosuppressive drugs during pregnancy.

INTRODUCTION: Immunosuppressive drugs and their active metabolites can cross the placental barrier and enter fetal circulation. The adverse effects on the fetus include chromosomal aberrations, structural malformations, organ-specific toxicity and intrauterine growth retardation. The aim of our study was to investigate the impact of "safe" and "contraindicated" immunosuppressive drugs on birth defects in juvenile Wistar rats after exposure of pregnant female rats to these drugs. MATERIAL AND METHODS: The study was conducted on 32 female Wistar rats, subjected to immunosuppressive regimens most commonly used in therapy of human kidney transplant recipients. The animals received drugs by oral gavage 2 weeks before pregnancy and during 3 weeks of pregnancy. RESULTS: Treatment with mycophenolate mofetil and everolimus turned out to be toxic. We have noticed a significantly reduced number of live births in all pregnant rats exposed to these drugs in combination with calcineurin inhibitors and prednisone. Malformations and histological changes of fetal organs were confirmed after mycophenolate mofetil exposure during pregnancy. CONCLUSIONS: Mycophenolate mofetil turned out to be more toxic when used with tacrolimus than with cyclosporin (delivery of live offspring was possible only in the latter group). Everolimus in combination with cyclosporin effectively suppressed the fetal maturation in utero, but did not contribute to the development of malformations.

Effects of an immunosuppressive treatment on the rat prostate.

The aim of this study was to determine the influence of different combinations of immunosuppressive drugs on the morphology, ultrastructure, and expression of proliferating cell nuclear antigen and cytoskeleton proteins in the rat dorsolateral prostate. The studies were conducted on 48 male Wistar rats. The animals were divided into eight groups: a control group and seven experimental groups. For 6 months, the animals in the experimental groups were administered a combination of drugs including rapamycin (Rapa), cyclosporin A, tacrolimus (Tac), mycophenolate mofetil, and prednisone (Pred), according to the standard three-drug regimens for immunosuppressive therapy used in clinical practice. An evaluation of the morphology and ultrastructure was conducted, and a quantitative evaluation of the expression of proliferating cell nuclear antigen and desmin- and cytokeratin-positive cells with weak, moderate, and strong expression was performed. The combination of Rapa, Tac, and Pred caused the smallest morphological and ultrastructural changes in the rat prostate cells. In the case of rats whose treatment was switched to Rapa monotherapy, a decreased percentage of proliferating cells of both the glandular epithelium and the stroma was found. Decreases in body weight and changes in the expression of cytokeratin and desmin were observed in all the experimental rats. The combination of Rapa, Tac, and Pred would seem to be the most beneficial for patients who do not suffer from prostate diseases. Our results justify the use of inhibitors of the mammalian target of Rapa in the treatment of patients with prostate cancer. The changes in the expression of cytoskeleton proteins may be the result of direct adverse effects of the immunosuppressive drugs, which are studied in this article, on the structure and organization of intermediate filament proteins.

The influence of exposure to immunosuppressive treatment during pregnancy on renal function and rate of apoptosis in native kidneys of female Wistar rats.

Pregnancy puts a significant additional strain on kidneys. The aim of our study was to investigate the impact of immunosuppressive drugs on changes in native kidneys in female Wistar rats after exposure during pregnancy. The study was conducted on 32 dams, subjected to immunosuppressive regimens commonly used in the therapy of human kidney transplant recipients (cyclosporine A, mycophenolate mofetil and prednisone; tacrolimus, mycophenolate mofetil and prednisone; cyclosporine A, everolimus and prednisone). The animals received drugs for 2 weeks before pregnancy and during 3 weeks of pregnancy. In all treated dams lower body weight (but not kidney mass) and alterations in serum sodium and chloride ions were found; serum creatinine concentration was increased in dams treated with cyclosporine A, everolimus and prednisone. All treatment groups of dams showed increased apoptosis in the distal tubules. In histological examination the changed intensity of acidophilic or basophilic cytoplasm of epithelial cells was found in kidneys of rats treated with calcineurin inhibitors, mycophenolate mofetil and prednisone. All immunosuppressive regimens caused abnormalities affecting nephron tubules. Regimens containing calcineurin inhibitors and mycophenolate mofetil caused higher rate of apoptosis and more pronounced histopathological changes. Regimen based on everolimus despite the lower rate of apoptosis in the proximal tubules and lower accumulation of kidney injury markers revealed higher serum creatinine concentration. Thus, interpretation which combination of drugs is better or worse for long-lasting functioning of kidneys in pregnant females requires further studies.

Effect of Immunosuppressive Therapy on Proteinogram in Rats.

BACKGROUND It has been observed that the use of immunosuppressive drugs in patients after transplantation of vascularized organs may be associated with changes in the concentration of certain fractions of plasma proteins. The concentration of these proteins was correlated with an increased risk of occurrence of stage 3 chronic kidney disease (CKD). This article examines the effect of the most commonly used immunosuppressive drugs on the concentration of plasma proteins in Wistar rats. MATERIAL AND METHODS The study involved 36 rats grouped according to the immunosuppressive regimen used (tacrolimus, mycophenolate mofetil, cyclosporine A, rapamycin, and prednisone). The rats in all study groups were treated with a 3-drug protocol for 6 months. The treatment dose was adjusted based on available data in the literature. No drugs were administered to the control group. The rats were sacrificed and blood samples collected to determine the concentration of plasma proteins using electrophoresis technique. RESULTS Statistically significant differences were observed between protein concentrations within the studied groups. The differences related to the proteins with masses of 195 kDa, 170 kDa, 103 kDa, and 58 kDa. CONCLUSIONS (1) Immunosuppressive drugs caused changes in the proteinogram of plasma proteins. (2) The strongest effect on rat plasma proteins was exerted by a regimen based on rapamycin. Intermediate, weak, and weakest effects were observed in regimens based on cyclosporine A, tacrolimus, and mycophenolate mofetil, respectively.

The Role of Klotho Protein in Chronic Kidney Disease: Studies in Animals and Humans.

The identification of Klotho gene was a major discovery as the gene encodes a protein regulating multiple functions. A defect in Klotho gene expression in mice results in a phenotype of premature aging including shortened life span, growth retardation, hypogonadism, skin and muscle atrophies, vascular calcification, cognition impairment, motor neuron degeneration and others. This phenotype is associated with phosphate balance disorders and underlines the major function of Klotho in mineral metabolism. As another 2 related paralogs were discovered (beta-Klotho, which is involved in bile acid and energy metabolism, and gamma-Klotho, with a yet to be defined function), this led to the revised naming of Klotho as alpha-Klotho. Two forms of alpha-Klotho protein have been reported: a membrane-bound and a soluble one. Membrane Klotho forms a complex with fibroblast growth factor (FGF) receptors and functions as an obligate co-receptor for the FGF-23 phosphatonin in distal tubules. The soluble form of Klotho seems to function as a humoral factor and regulates glycoproteins on the cell surface including ion channels and growth factors. There is data suggesting that soluble Klotho exerts phosphaturic effects independently of FGF-23. Circulating soluble Klotho is produced either by proteolytic cleavage of the extracellular domain of the transmembrane form by two membrane-anchored proteases (ADAM10 and ADAM17) or by alternative mRNA splicing. In animal models Klotho has been shown to exert pleiotropic actions, including cytoprotection, anti-oxidation, anti-apoptosis, protection of vasculature, promotion of angiogenesis and vascularization, inhibition of fibrogenesis and preservation of stem cells. The exact diagnostic and therapeutic role of Klotho in humans is not fully known yet. The article presents the role of Klotho in physiology and different stages of chronic kidney disease (CKD).

Wegener's granulomatosis and pyoderma gangrenosum--rare causes of facial ulcerations.

BACKGROUND: Pyoderma gangrenosum (PG) is caused by immune system dysfunction, and particularly improper functioning of neutrophils. At least half of all PG patients also suffer from autoimmunological diseases, one of which is Wegener granulomatosis (WG). The purpose of this article was to compare cases of patients with WG and PG in terms of their clinical course, histopathology, and applied treatment. In both, histopathological features are not fully distinct. Data from microbiological and immunological evaluation and clinical presentation are required to establish the diagnosis. We also present the case of a patient with WG and deep facial skin lesions not responding to standard treatment. METHODS: Systematic review of the literature in PubMed using the search terms "Wegener granulomatosis AND Pyoderma gangrenosum" and case report. RESULTS: The finding of 22 reports in the literature (PubMed) suggests that it is a rare phenomenon. This study revealed a similar rate of comorbidity of WG and PG in both genders and an increased incidence of both diseases after the age of 50. Among skin lesions there was a dominance of ulceration, most often deep and painful, covering a large area with the presence of advanced necrosis and destruction of the surrounding tissue. The most common location proved to be the cervical-cephalic area. The most popular treatment included steroids with cyclophosphamide. DISCUSSION: The rarity of the coexistence of these two diseases results in a lack of effective therapy. In such cases sulfone derivatives are still effective and provide an alternative to standard immunosuppression methods. Hyperbaric therapy and plasmapheresis can also play an important complementary role.

Does Immunosuppressive Therapy Affect Markers of Kidney Damage?

BACKGROUND: Markers currently used to detect kidney damage are effective in both early (KIM-1, NGAL) and late (MCP-1, MMP, TIMP) stages of renal tubular damage, indicating the progression of chronic kidney disease. Immunosuppressive drugs may damage the transplanted organ through their direct toxic effects and by contributing to the development of chronic fibrosis and tubular atrophy. The aim of this study was to determine if immunosuppressive drugs per se affect the concentration of kidney damage markers, by using concentrations and doses of immunosuppressive within therapeutic, not toxic, levels in rat blood. MATERIAL AND METHODS: The study involved 36 rats grouped according to the immunosuppressive regimen used (tacrolimus, mycophenolate mofetil, cyclosporin A, rapamycin, and prednisone). The rats were treated with a 3-drug protocol for 6 months. No drugs were administered to the control group. The blood samples were collected to determine the concentration of kidney damage markers by using enzyme-linked immunosorbent assay (ELISA). RESULTS: 1. In the groups receiving regimens based on cyclosporin A (CyA), significantly higher concentrations of KIM-1 in plasma was observed compared to cases not treated with drugs. 2. The use of tacrolimus was associated with increased concentrations of MCP-1 in plasma and rapamycin was associated with decreased concentrations of MCP-1 in plasma. 3. Rapamycin induces an unfavorable, profibrotic imbalance between metalloproteinase-9 and its inhibitor, TIMP-1. CONCLUSIONS: Commonly used immunosuppressive drugs influence the concentration of blood markers of kidney damage. This fact should be taken into account when analyzing the association between the concentration of these markers and pathological processes occurring in the transplanted kidney.

The influence of immunosuppressants on the morphology, proliferating cell nuclear antigen (PCNA) and apoptosis in the rat ventral prostate.

AIM: Analysis of the impact of immunosuppressants on apoptosis and PCNA in the rat ventral prostate. METHOD: The studies were performed on 48 male Wistar rats. The animals were divided into a control group and 7 experimental groups. For 6 months, the rats were administered drugs such as: rapamycin (Rapa), cyclosporin A (CsA), tacrolimus (Tac), mycophenolate mofetil (MMF) and glucocorticosteroids (GS). During section of the rats, prostate ventral lobes were obtained. Morphological evaluation (HE, PAS), TUNEL assay, PCNA expression analysis and quantitative image computer analysis were performed. RESULTS: The highest percentage of apoptosis in epithelial cells was observed in groups which received two combinations of drugs: (V) CsA, MMF, GS and (VII) Tac, MMF, GS. A much lower percentage of apoptotic epithelial cells was found in the groups where the treatment schemes included rapamycin throughout the duration of the study. Interestingly, the conversion of the treatment to rapamycin caused a significant reduction of apoptosis in epithelial cells as well as in proliferation in both epithelial and stromal cells. CONCLUSIONS: On one hand, the obtained results may explain the anticancer activity of rapamycin in reducing the proliferation of epithelial cells, and on the other hand the adverse effect of rapamycin in the form of reduced regeneration of these cells. Taking into account the prostate in isolation from other organs/systems, the dosage scheme with Rapa, Tac and GS would appear to be the most favorable, due to the smallest morphological changes.

The effect of immunosuppressive therapy on renal cell apoptosis in native rat kidneys.

AIM: To analyse the impact of the most commonly used immunosuppressive drugs on the occurrence of apoptosis in the native kidneys of Wistar rats. METHOD: The study involved 36 rats. the animals being grouped according to the immunosuppressive regimen used (tacrolimus, mycophenolate mofetil, cyclosporine A, rapamycin and prednisone). The rats in all study groups were treated with a 3-drug protocol for 6 months. The medication dose was adjusted based on available literature data. No drugs were administered to the control group. The rats were then killed. Autopsies of all animals were performed and the kidneys were isolated for histopathology (HE + PAS). To assess cell apoptosis the TUNEL reaction was performed. Blood trough levels of immunosuppressive drugs as well as the parameters of peripheral blood were determined. RESULTS: 1. In rats treated with cyclosporine A distal nephron tubules were characterised by more pronounced apoptosis. 2. In tacrolimus-treated rats a lower intensity of apoptosis was found in the distal tubules. 3. In rapamycin-treated rats the apoptosis was inhibited both in the distal and proximal nephron tubules. 4. In MMF treated rats intense apoptosis was observed in the proximal nephron tubules. 5. There were no significant changes in renal histopathology (HE + PAS). CONCLUSIONS: The apoptosis in nephron tubules caused by immunosuppressive therapy is not accompanied by any histopathological changes (eg fibrosis, inflammation, tubular atrophy, vacuolation of the tubular cells) in light microscopy.

Effects of immunosuppressive treatment on protein expression in rat kidney.

The structural proteins of renal tubular epithelial cells may become a target for the toxic metabolites of immunosuppressants. These metabolites can modify the properties of the proteins, thereby affecting cell function, which is a possible explanation for the mechanism of immunosuppressive agents' toxicity. In our study, we evaluated the effect of two immunosuppressive strategies on protein expression in the kidneys of Wistar rats. Fragments of the rat kidneys were homogenized after cooling in liquid nitrogen and then dissolved in lysis buffer. The protein concentration in the samples was determined using a protein assay kit, and the proteins were separated by two-dimensional electrophoresis. The obtained gels were then stained with Coomassie Brilliant Blue, and their images were analyzed to evaluate differences in protein expression. Identification of selected proteins was then performed using mass spectrometry. We found that the immunosuppressive drugs used in popular regimens induce a series of changes in protein expression in target organs. The expression of proteins involved in drug, glucose, amino acid, and lipid metabolism was pronounced. However, to a lesser extent, we also observed changes in nuclear, structural, and transport proteins' synthesis. Very slight differences were observed between the group receiving cyclosporine, mycophenolate mofetil, and glucocorticoids (CMG) and the control group. In contrast, compared to the control group, animals receiving tacrolimus, mycophenolate mofetil, and glucocorticoids (TMG) exhibited higher expression of proteins responsible for renal drug metabolism and lower expression levels of cytoplasmic actin and the major urinary protein. In the TMG group, we observed higher expression of proteins responsible for drug metabolism and a decrease in the expression of respiratory chain enzymes (thioredoxin-2) and markers of distal renal tubular damage (heart fatty acid-binding protein) compared to expression in the CMG group. The consequences of the reported changes in protein expression require further study.

[Old age--neither sour nor bitter]. / Starosc--ani kwasna, ani gorzka.

The development of medicine involves prolongation of human life. In many cases, however, chronic diseases, quite common in the elderly, make the quality of life very poor. We put the question: why we--the doctors--are not able to cope with the problem and whether the pharmacological treatment actually helps? A common medical practice is the use of proton pump inhibitors for various, often nonspecific disorders of the gastrointestinal tract. Statistics point to the overuse of the drugs from this group, also in the elderly. Despite the belief in the safety of such proceedings, proton pump inhibitors may pose a significant threat to older patients contributing to the symptoms worsening, and significantly affecting the mechanisms of acid-base balance. Inhibition of gastric acid secretion in the stomach is not a golden receipt in the case of dyspeptic symptoms, especially in people with the elderly. In many of them achlorhydria or hipochlorhydria is diagnosed. In others, such treatment, may not bring an expected relief in symptoms, while contributing to disturbances of acid-base balance, and--indirectly--have an adverse effect on renal function. We suggest moderation in the use of proton pump inhibitors to bring patients to a real, and not quasi wellness.

Three clinical cases of nonrespiratory acidosis in kidney transplant recipients receiving anti-CMV therapy.

BACKGROUND: To preserve kidney graft function it is necessary to use ganciclovir or valganciclovir as a therapy for fresh CMV infection or prophylaxis in high-risk kidney transplant recipients. Ganciclovir-induced lactic acidosis has thus far not been reported. CASE REPORT: Three cases of nonrespiratory acidosis in kidney transplant recipients receiving ganciclovir or valganciclovir as anti-CMV therapy or prophylaxis are presented. Lactic acidosis developed in 2 patients, and the other patient had nonrespiratory acidosis of unknown origin. The possible mechanism of the development of lactic acidosis in presented cases is explored. CONCLUSIONS: The analysis of the described cases cannot eliminate the potential negative influence of anti-CMV therapy on acid-base equilibrium, especially with coexisting active viral infection.

Minimal-Change Disease Secondary to Borrelia burgdorferi Infection.

Lyme borreliosis is a chronic illness caused by tick-transmitted spirochete Borrelia burgdorferi. Borreliosis can be extremely threatening if it is not diagnosed and treated in early stages. Kidneys are not typically involved in the disease. However, in infected dogs, Lyme nephritis is present in 5-10% of cases. It is associated with rapidly progressing renal failure. Histopathological examination shows mesangial proliferative glomerulonephritis with diffuse tubular necrosis, (Dambach et al. (1997)). In available literature, there were reports of human's glomerulonephritis associated with Borrelia burgdorferi infection. These cases refer to membranous and mesangial proliferative glomerulonephritis (Kirmizis and Chatzidimitriou (2010), Zachäus (2008), and Kirmizis et al. (2004)). In this paper, we present the case of minimal-change disease (MCD) as a result of Borrelia burgdorferi infection.

Association of transcription factor 7-like 2 (TCF7L2) gene polymorphism with posttransplant diabetes mellitus in kidney transplant patients medicated with tacrolimus.

New onset posttransplant diabetes mellitus (PTDM) has a high incidence after kidney transplantation in patients medicated with tacrolimus. PTDM can adversely affect patient and graft survival. The pathophysiology of PTDM closely mimics type 2 diabetes mellitus (T2DM). One of the possible genetic factors predisposing individuals to PTDM might be a polymorphism in the transcription factor 7-like 2 gene (TCF7L2). This polymorphism has previously been associated with increased risk of T2DM in the general population. Therefore, the present study aimed to evaluate TCF7L2 polymorphisms in PTDM in kidney transplant patients medicated with tacrolimus. Non-diabetic kidney transplant patients medicated with tacrolimus (n = 234) were genotyped for the presence of TCF7L2 gene variants (rs12255372 and rs7903146) using TaqMan probes. Of the 234 patients, 66 patients had developed PTDM and 168 had not. Frequencies of the studied single nucleotide polymorphisms (SNPs) did not differ significantly between the study groups. Moreover, haplotype analyses failed to detect any associations between TCF7L2 haplotypes and PTDM. However, in late-onset PTDM (developed later that 2 weeks from transplantation), frequencies of the rs7903146 TT genotype and T minor allele were significantly increased compared to non-PTDM controls (17.9% vs. 5.9%, p = 0.017, OR: 4.13, 95% CI: 1.19-14.33 for TT genotype, 39.3% vs. 25.9%, p = 0.038 for T allele). If the application of TCF7L2 rs7903146 SNPs as a marker for PTDM is confirmed by further independent studies, replacing tacrolimus with other immunosuppressants could be warranted in patients at high risk of PTDM, as diagnosed by TCF7L2 genotyping.

Urinary hepatocyte growth factor indicates ischemia/reperfusion injury after kidney transplantation.

INTRODUCTION: Despite the development of immunosuppressive regimens in kidney transplantation, long-term graft survival rates have not increased significantly. One of the causes of long-term graft loss is ischemia-reperfusion insult. Hepatocyte growth factor (HGF) is a regenerative factor produced in response to injury. OBJECTIVES: Our aim was to assess the effect of HGF and xanthine oxidase (indicators of ischemia/reperfusion insult) on early and late kidney function. PATIENTS AND METHODS: In 17 patients, HGF levels in urine and xanthine oxidase activity in blood were examined 1, 7, 14, 30 days, 3 and 6 months after kidney transplantation. We also measured 24-hour diuresis and serum creatinine levels after transplantation. RESULTS: Urinary HGF levels were highest 1 day after transplantation. During the following week, it rapidly decreased and was maintained at similar levels in the later period. Creatinine at 1 day showed a positive correlation with urinary HGF levels at 1 day and at 3 months (R = 0.54, P <0.05 and R = 0.82, P <0.01, respectively). Creatinine at 7 days positively correlated with HGF levels at 6 months (R = 0.82, P <0.05). HGF levels at 1 day and at 6 months positively correlated with xanthine oxidase activity at 1 day (R = 0.73, P <0.001 and R = 0.77, P <0.02, respectively). A negative correlation was observed between HGF levels at 6 months and diuresis 1 and 7 days after transplantation (R = -0.99, P <0.00 001 and R = -0.77, P <0.05, respectively). CONCLUSIONS: Urinary HGF is a good marker of perioperative kidney damage and may affect long-term graft function.

Does oxidative stress affect the activity of the sodium-proton exchanger?

INTRODUCTION: Accumulation of reactive oxygen species (ROS) takes place in patients with chronic renal failure (CRF). Oxidative stress causes disorders in the activity of the sodium-proton exchanger (NHE). Studies on NHE in CRF produced results that are discrepant and difficult to interpret. The aim of this study was to demonstrate that oxidative stress had an effect on the activity of NHE. METHODS: We enrolled 87 subjects divided into 4 groups: patients with CRF treated conservatively; patients with CRF hemodialyzed without glucose--HD-g(-); patients with CRF hemodialyzed with glucose--HD-g(+); controls (C). The activity of NHE, the rate of proton efflux V(max), Michaelis constant (Km), and the concentration of thiobarbituric acid-reactive substances (TBARS, an indicator of oxidative stress) in plasma, as well as the concentration of reduced glutathione in blood were determined. RESULTS: The concentration of TBARS was significantly higher in hemodialyzed patients before and after dialysis and in patients with CRF on conservative treatment in comparison with group C. TBARS in plasma correlated negatively with VpH(i)6.4 in group C and with V(max) and VpH(i)6.4 after HD in group HD-g(-). We found that the concentration of creatinine correlated with TBARS (p < 0.0001; r = +0.51) in the conservatively treated group. CONCLUSION: We observed a marked oxidative stress and decreased NHE activity when dialysis was done without glucose, whereas patients dialyzed with glucose demonstrated a relatively low intensity of oxidative stress.