Search

Churg–Strauss syndrome (CSS) is a granulomatous small-vessel vasculitis. Asthma is seen in the majority of patients with CSS, but atypical nonasthmatic forms of CSS are also being recognized. We herein describe a 67-year-old woman with a history of chronic pyelonephritis and drug allergy reactions who was admitted to our hospital because of worsening renal function preceded by fever, purpura, sinusitis, and a positive urine culture that confirmed a urinary infection. She was initially treated with pipemidic acid for 7 days, followed by clarithromycin for sinusitis. Laboratory tests on admission showed an absolute eosinophil count of 1750 cells/µL and serum creatinine concentration of 4.72 mg/dL. Urine and blood cultures showed no growth. Kidney biopsy revealed crescent formations with diffuse interstitial fibrosis and foci of eosinophil infiltration. An atypical form of CSS was diagnosed based on tissue eosinophilia, peripheral eosinophilia, and sinusitis. Intravenous methylprednisolone and cyclophosphamide pulse therapy together with hemodialysis treatment improved the patient’s clinical condition but did not resolve the kidney damage. The onset of an atypical form of CSS in our patient manifested as symptoms and signs mimicking those of chronic pyelonephritis and drug allergy reactions. The patient’s chronic kidney disease finally progressed to dialysis dependence.

Olive (Olea europaea L.) leaf extract (OLE) possesses powerful antioxidant, antihyperlipidemic, and anti-inflammatory properties. The aim was to investigated the effects of OLE on the hyperlipidemia, antioxidant defense, heme oxygenase/biliverdin reductase (HO/BVR) pathway, inflammation, and fibrosis in spontaneously hypertensive rats with focal segmental glomerulosclerosis (FSGS, a progressive form of chronic kidney disease) induced by adriamycin (2 mg/kg, i.v., twice in a 21-day period). Daily treatment of OLE (80 mg/kg, p.o.) for 6 weeks suppressed protein oxidation and lipid peroxidation (p lt .01 and p lt .001, respectively), significantly increased antioxidant enzymes activities and normalized antioxidant capacity, leading to the improvement of antioxidant defense independently of the HO/BVR pathway. Furthermore, the values of triglycerides (p lt .01), total, and low-density lipoprotein cholesterol (p lt .05, both) were improved by OLE. OLE strongly prevented glomerulosclerosis, interstitial inflammation, and fibrosis (renal injury score, FSGS: 8 +/- 0.45 vs. FSGS+OLE: 4.20 +/- 1.07; p lt .01), as evidenced by normalized fibronectin content (p lt .001), suppressed interstitial inflammatory cells infiltration and collagen deposition, without changing cytokines expressions. OLE decreased blood pressure with a tendency to reduce urine albumin loss. These data suggest that OLE may be effective in slowing down the progression of FSGS.

BackgroundProtein arginine methyltransferase-1 (PRMT1) is associated with the progression of various tumor types and the process of epithelial to mesenchymal transition (EMT). However, the expression of PRMT1 in renal cell tumors (RCT) is unknown.MethodsWe evaluated PRMT1 immunohistochemical (IHC) expression on tissue microarray (TMA) of 208 specimens of RCT, including clear cell renal cell carcinomas (ccRCC), papillary RCC type I and II (pRCC I and II), chromophobe RCC (chRCC), renal oncocytomas (RO), collecting duct carcinomas - Bellini (CDC) and multilocular cystic renal cell neoplasms of low malignant potential (MLCRN-LMP). Moreover, a subset of ccRCC, pRCC, chRCC, RO were also studied using conventional sections. PRMT1 expression in tumor tissue was compared to the IHC expression of EMT-related transcription factors (ZEB1, RUNX1, and TWIST1) and cell surface markers (ß-catenin, N- and E-cadherin). Additionally, qRT-PCR expression of PRMT1 in ccRCC, pRCC, and chRCC was evaluated and the results were compared to the mRNA PRMT1 transcript profiling data in The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) cohort.ResultsPRMT1 immunoreactivity was observed in the majority of ccRCC, RO, all MLCRN-LMP, but in a minority of chRCC (p = 0.044), and it was associated with low grade and low stage ccRCC (p = 0.014; p = 0.044, respectively). ZEB1 immunoreactivity was noted in all RO, in minority of chRCC and neither of MLCRN-LMP (p p = 0.028;p p = 0.019). PRMT1 and ZEB1 expression were associated with better cancer-specific survival in patients with ccRCC (p = 0.029;p = 0.009, respectively). In multivariate analysis, ZEB1 expression was an independent prognostic factor for cancer-specific survival (hazard ratio [HR], 0.367;p = 0.026). Significant IHC heterogeneity was observed in PRMT1, ZEB1 and TWIST1 expression (p p = 0.017;p = 0.040;p = 0.044;p = 0.009, respectively). Relative mRNA-PRMT1 expression in both cohorts was down-regulated in tumor tissue compared to non-tumor parenchyma (p = 0.009). Unlike in our samples, mRNA-PRMT1 expression in the TCGA cohort was not correlated to ccRCC tumor stage or grade. PRMT1, ZEB1, and TWIST1 expression were not associated with EMT related aberrant ß-catenin expression, a gain of N-cadherin or loss of E-cadherin expression. Only RUNX1 was associated with a gain of N-cadherin (p = 0.003).ConclusionsIHC expression of PRMT1 may be characteristic for low grade and low stage ccRCC, while the homogenous loss of PRMT1 may be significant for high grade and high stage ccRCC. Both, PRMT1 and/or ZEB1 expression, could be associated with better survival of the patients with ccRCC.

Introduction. Juxtaglomerular cell tumor (JGCT) or reninoma is a very rare cause of curable hypertension among young people. The early diagnosis is the most important based on the clinical presentation, hormonal and radiological findings observed on computed tomography (CT) and/or magnetic resonance imaging (MRI). The final confirmation of the JGCT is the lateralization of the plasma renin activity (PRA) during the selective renal venous sampling. Case report. This report presents a typical case of young women with JGCT which was manifested for the first time with severe hypertension during the pregnancy and was the reason of fetal death. After the miscarriage, the diagnosis of JGCT was made by the CT scanning and confirmed by the selective renal venous sampling. After the partial nephrectomy, the blood pressure and serum potassium normalized without the medications. Conclusion. Reninoma should be considered in the differential diagnosis as a cause of severe hypertension in pregnancy and also should be suspected in young hipertensives (especially females) with hypokalemia and secondary hyperaldosteronism after the exclusion of other causes particularly renal artery stenosis. A dynamic contrastenhanced CT, MRI and selective renal venous sampling are the most important tools in the diagnosis of JGCT.

TASK2 (K2P5. 1, KCNK5) is a two-pore domain K⁺ channel belonging to the TALK subgroup of the K2P family of proteins. TASK2 expression has been reported in a variety of cells and tissues ranging from kidney to immune cells and including specific neurons, its proposed functions spanning from involvement in the regulation of cell volume to control of excitability. The purpose of this study was to determine the tubule location ofthe TASK2 K⁺ channel protein in frog kidney applying polyclonal antibody against the carboxyl terminus of human TASK2 (KCNK5) protein. Immunohistochemical analysis revealed that TASK2 is expressed on distal tubules and proximal epithelial cells. TASK2 is strongly expressed predominantly on the luminal part ofthe proximal epithelial cells and slightly cytoplasmatic staining is expressed. Distal tubules showed diffuse cytoplasmatic staining as well as slight staining on the apical parts ofthe cells. These findings suggest that the TASK2 K⁺ channel has cell-specific roles in renal potassium ion transport.

Neural cell adhesion molecule (NCAM) and fibroblast growth factor receptor 1 (FGFR1) cross-talk have been involved in epithelial-to-mesenchymal transition (EMT) process during carcinogenesis. Since EMT also contributes to maladaptive repair and parenchymal damage during renal fibrosis, we became encouraged to explore the role of NCAM/FGFR1 signaling as initiating or driving forces of EMT program in cultured human proximal tubular epithelial cells (TECs). TECs stimulated with TGF-β1 (10ng/mL) was used as an established in vitro EMT model. TGF-β1 downstream effectors were detected in vitro, as well as in 50 biopsies of different human kidney diseases to explore their in vivo correlation. NCAM/FGFR1 signaling and its modulation by FGFR1 inhibitor PD173074 (100nM) were analyzed by light microscopy, immunolabeling, qRT-PCR and scratch assays. Morphological changes associated with EMT appeared 48h after TGF-ß1 treatment and was clearly apparent after 72 hours, followed by loss of CDH1 (encoding E-Cadherin) and transcriptional induction of SNAI1 (SNAIL), SNAI2 (SLUG), TWIST1, MMP2, MMP9, CDH2 (N-Cadherin), ITGA5 (integrin-α5), ITGB1 (integrin-β1), ACTA2 (α-SMA) and S100A4 (FSP1). Moreover, at the early stage of EMT program (24 hours upon TGF-β1 exposure), transcriptional induction of several NCAM isoforms along with FGFR1 was observed, implicating a mechanistic link between NCAM/FGFR1 signaling and induction of EMT. These assumptions were further supported by the inhibition of the EMT program after specific blocking of FGFR1 signaling by PD173074. Finally, there was evidence for an in vivo TGF-β1 pathway activation in diseased human kidneys and correlation with impaired renal excretory functions. Collectively, NCAM/FGFR1 signaling appears to be involved in the initial phase of TGF-ß1 initiated EMT which can be effectively suppressed by application of FGFR inhibitor. peerReviewed

Biopsy registries are one of the most important sources of accurate epidemiological data and the clinical presentation of renal diseases. A detailed analysis of clinicopathologic correlations over a period of 20 years (1987-2006) was performed earlier by our centre. The aim of this study was to check the current state and to register possible changes in clinicopathologic findings recorded under better socioeconomical circumstances and new management. Records of 665 renal biopsies performed at our institution were prospectively followed from 2007 to 2014. The results were compared with our previously published data. The average annual incidence of renal biopsies increased by 10% and included more elderly patients. Nephrotic syndrome (NS) remained the most common clinical indication for biopsy, while acute kidney injury participated more frequently than in the previous study (p 0.001). Membranous nephropathy (MN) was still the most common cause of NS. Primary glomerulonephritis (PGN) remained the most prevalent disease, while MN was the most prevalent PGN. In comparison with the earlier period, MN was a more common diagnosis (p = 0.002), while the prevalence of mesangioproliferative non-IgA nephropathy decreased significantly during the time (p = 0.012). LN remained the most frequent secondary glomerulonephritis. The pathohistological pattern of renal biopsy remained largely unchanged during time. However, acute kidney injury was more frequently an indication for biopsy in the current study. The significant increase of biopsied elderly patients is due to the rise in their relative numbers in our population.

Introduction. Post-transplant lymphoproliferative disorder (PTLD) is a common malignancy following organ transplantation. Risk for PTLD is associated with the use of anti-thymocyte globulin in the prevention and treatment of acute rejection following kidney transplantation. Case Outline. We report a case of fatal PTLD presented with sudden onset of fever. A 33-year-old male patient with primary diagnosis of left kidney agenesia underwent kidney transplantation six years following hemodialysis treatment initiation. Deceased donor was a 66-year-old female whose cause of death was cerebrovascular accident. Immunosuppressive regimen consisted of basiliximab, corticosteroids, tacrolimus, and mycophenolate mofetil. Six months upon transplantation the patient was hospitalized due to fever of unknown origin. All microbiological samples were negative, but abdominal ultrasound revealed round solid mass in the right native kidney. Right nephrectomy was performed showing tumor 35 x 35 x 20 mm in size within the 70 x 40 x 35 mm kidney. Pathohistological analysis confirmed very rare monomorphic B-cell PTLD - B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma. Conclusion. We consider this case of PTLD following kidney transplantation particular because of the tumor mass in native kidney after basiliximab induction and rare pathohistology. In a transplanted patient with fever, PTLD must always be considered, irrespective of immunosuppressive regimen.

The ideal agent for prevention and treatment of uterine abnormal contractility has not been found. The polyphenol resveratrol possesses a wide spectrum of pharmacologic properties, but its influence on the contractility of human myometrium is not defined. The present study evaluated the effect of resveratrol on the oxytocin-induced contractions of human term pregnant myometrium in vitro and the contribution of different K(+) channels to resveratrol action. Resveratrol induced a concentration-dependent relaxation of myometrium contractions (pD2 value and maximal responses were 4.52 and 82.25%, respectively). Glibenclamide, a selective blocker of ATP-sensitive (KATP), iberiotoxin, a selective blockers of big-calcium sensitive (BK(Ca)) and 4-aminopiridine, a non-selective blocker of voltage-sensitive (Kv) channels induced a significant shift to the right of the concentration-response curves of resveratrol. Inhibition achieved by 0.1 mM resveratrol was insensitive to all K(+) channel blockers. A K(+) channel opener, pinacidil, inhibited oxytocin-induced contractions of pregnant myometrium with comparable potency and efficacy to resveratrol (pD2 values and maximal relaxation were 4.52 and 83.67%, respectively). Based on K(+) channel opener/blocker affinities, it appears that the inhibitory response of resveratrol involves different myometrial K(+) channels. When applied in high concentrations, resveratrol has an additional K(+)-channel-independent mechanism(s) of action. Furthermore, immunohistochemistry staining and western blot analyses detected the presence and distribution of KATP, BK(Ca) and Kv channel proteins in pregnant myometrium.

Down-regulation of nitric oxide synthase (NOS) and NO deficiency in the kidneys have been implicated in the pathogenesis of chronic kidney disease (CKD). In this study we examined the effects of losartan, tempol, and combined treatment on three NOS isoforms expressions, kidney NO content and NOS correlation with renal function and structure in the early stage of adriamycin (ADR)-induced CKD in spontaneously hypertensive rats (SHR). Rats were divided into control group, and four other groups which were treated with ADR and received vehicle, losartan (L, angiotensin II type 1 receptor blocker), tempol (T, redox-cycling nitroxide) or T+L treatment (by gavage) in a six-week study. Reduction of all NOS isoforms expressions were significantly improved by losartan or tempol, and correlated with proteinuria amelioration. Combined treatment induced down-regulation of constitutive NOS isoforms, whilst inducible NOS was up-regulated and followed by increased nitrite content and a significant decline in the glomerular filtration rate. Losartan or tempol prevented ADR-induced neoexpression of vimentin in the glomeruli and tubulointerstital areas, whereas de novo vimentin expression was still observed in the atrophic tubules and in the interstitial fibroblasts and myofibroblasts in combined treatment. It can be concluded that single treatments, contrary to combined, were effective in improving NO bioavailability and slowing down the progression of CKD.

Neural cell adhesion molecule (NCAM) is important for cell migration and it could be expressed in some renal cell carcinoma (RCC). In recent decades, the incidence of RCC has been steadily rising by 2-4% each year. In this study NCAM expression and correlation with nuclear grade in different RCC were analyzed. We analyzed NCAM expression on 7 different RCC cell lines and 32 different RCC by immunohistochemistry, immunofluorescence, Western blot and FACS analysis. NCAM expression is detected in 6 cell lines and 16 RCC cases. NCAM-140 kDa isoform is expressed in different RCC and RCC cell lines. NCAM expression in non-invasive clear cell RCC is lower than in clear cell RCC with high nuclear grade. Expression of NCAM is not exclusive for specific RCC type, so NCAM can not be used as a specific diagnostic marker for RCC. NCAM expression is in correlation with nuclear grade in clear cell RCC, suggesting that NCAM expression is involved in aggressive behavior and metastatic potential in RCC.

Introduction. Autosomal recessive polycystic kidney disease is the most common heritable cystic renal disease occurring in infancy and childhood. The clinical spectrum of signs and symptoms of this disease is widely variable ranging from perinatal death to a milder progressive form, which cannot be diagnosed until adolescence. Case Outline. A female neonate born in the 35th/36th week of gestation. The findings of all standard medical examinations of the neonate done by the mother were within normal limits. A few days before delivery physicians at a regional medical centre revealed enlarged kidneys and oligohydramnios. The delivery was performed by caesarean section. The vital functions of the newborn were in critical condition so that she was referred to the University Children's Hospital in Belgrade. Soon after admission, despite all undertaken measures, the infant died. Autopsy was done at the Institute of Pathology of the Belgrade Clinical Centre. All findings were typical for autosomal recessive polycystic kidney disease. The kidneys were hugely enlarged, with cystically dilated collecting ducts that almost completely replaced the renal parenchyma. The lungs were mildly hypoplastic. The liver showed dilated portal spaces, with multiple irregularly branching bile ducts. The cause of death was respiratory distress and renal failure. Conclusion. In all cases of congenital anomalies of the kidney with lethal ending it is necessary to perform autopsy and aimed genetic investigation.

Background. The aim of the study was to investigate the antihypertensive effects of angiotensin II type-1 receptor blocker, losartan, and its potential in slowing down renal disease progression in spontaneously hypertensive rats (SHR) with adriamycin (ADR) nephropathy. Methods. Six-month-old female SHR were randomly selected in six groups. Two control groups (SH(6), SH(12)) received vehicle. Groups ADR(6), ADR+LOS(6) and ADR(12), and ADR+LOS(12) received ADR (2 mg/kg/b.w. i.v.) twice in a 3-week interval. Group ADR+LOS(6) received losartan (10 mg/kg/b.w./day by gavages) for 6 weeks and group ADR+LOS(12) for 12 weeks after second injection of ADR. Animals were killed after 6 or 12 weeks, respectively. Haemodynamic measurements were performed on anaesthetized animals, blood and urine samples were taken for biochemical analysis and the left kidney was processed for morphological studies. Results. Short-term losartan treatment, besides antihypertensive effect, improved glomerular filtration rate and ameliorated glomerulosclerosis resulting in decreased proteinuria. Prolonged treatment with losartan showed further reduction of glomerulosclerosis associated with reduced progression of tubular atrophy and interstitial fibrosis, thus preventing heavy proteinuria and chronic renal failure. Losartan reduced uraemia and increased urea clearance in advanced ADR nephropathy in SHR. Histological examination showed that losartan could prevent tubular atrophy, interstitial infiltration and fibrosis in ADR nephropathy. Conclusion. Losartan reduces the rate of progression of ADR-induced focal segmental glomerulosclerosis to end-stage renal disease in SHR.

Tumour mitotic index represents a number of dividing cells per 100 tumour cells. It is the oldest and most frequently used parameter of cell proliferation kinetics in tumours, which is, in addition to numerous immunohistochemical and other markers, still routinely practised as a golden standard. Determination is dependent on urgent tissue fixation, fixative type, manner and procedure of staining, thickness of tissue sections, statistical expression of mitotic count, tissue and microscopic field sampling as well as a counting protocol. When the identical counting techniques are applied, determination of tumour mitotic index becomes an essentially reproductive method. Proposal for routine usage is to express the number of mitotic figures in standard vision area of 2 mm2. Proceeding from minimal variability of mitotic time duration, there were showed a few original formulas which connect mitotic index, acquired by stereological methodology, with differential equation of tumour growth function. In this mathematical way, it is possible to connect structure of the tumour with tumour growth kinetics parameters, for example with potential doubling time. This approach provides growth kinetic examination of once occurring measured human solid tumours, according to their morphology. Tumour mitotic index has been actually applied in classification, biological behaviour prediction, grading, prognosis, evaluation of relapse potential, malignant transformation and metastasis, treatment decision and therapy effect follow-up. In some malignant tumours, such as breast carcinoma, it is an independent prognostic factor.

Ischemic acute kidney injury is characterized by renal vasoconstriction, filtration failure, tubular obstruction, tubular backleak and overproduction of angiotensin II and reactive oxygen species. Considering this complexity, the aim of our study was to investigate the effects of angiotensin II type-1 receptor blocker - Losartan and superoxide anion scavenger - Tempol, in a combined treatment on acute kidney injury in postischemic hypertensive rats. The experiment was performed in anesthetized, adult male spontaneously hypertensive rats. The right kidney was removed and the left renal artery was occluded for 40 minutes. Experimental groups received combined treatment (Losartan + Tempol) or saline in the femoral vein 5 minutes before, during and 175 minutes after clamp removal. Hemodynamics and biochemical parameters were measured and kidney specimens were collected 24h after reperfusion. Histological examination was performed by optical microscopy. Combined treatment improves renal haemodynamics parameters which were exacerbated due to acute kidney injury. Acute kidney injury significantly decreased creatinine and urea clearance and increased lipid peroxidation in the plasma. Treatment with Losartan and Tempol induced a significant increase of creatinine and urea clearance. Lipid peroxidation in the plasma decreased and glutathione peroxidase enzyme activity in the erythrocytes increased after Losartan + Tempol treatment. This combined treatment reduced cortico-medullary necrosis and tubular dilatation in the kidney. Our results indicate that synergism of Losartan and Tempol treatment could have beneficial effects on blood pressure and kidney function, during postischemic acute kidney injury development in experimental hypertension. Glavne karakteristike ishemične akutne bubrežne slabosti su: renalna vazokonstrikcija, pad glomerulske filtracije, tubularna opstrukcija, vraćanje glomerulskog filtrata u intersticijum tubula i prekomerna produkcija angiotenzina II i reaktivnih vrsta kiseonika. Uzimajući u obzir kompleksnost ovog poremećaja, cilj ove studije je bio da istraži efekte kombinovanog tretmana blokatora angiotenzin II receptora tip 1 - Losartana i sakupljača superoksidnog anjona - Tempola u modelu ishemične bubrežne slabosti kod hipertenzivnih pacova. Eksperiment je urađen na odraslim anesteziranim mužjacima hipertenzivnih pacova. Desni bubreg je uklonjen, dok je na levoj renalnoj arteriji urađena okluzija u trajanju od 40 minuta. Eksperimentalne grupe su primile kombinovani tretman (Losartan+Tempol) ili fiziološki rastvor u femoralnu venu, 5 minuta pre i 175 minuta nakon uklanjanja kleme sa renalne arterije. Hemodinamski i biohemijski parametri su izmereni, a uzorci bubrega uzimani su 24 časa nakon reperfuzije. Histološka ispitivanja su rađena pomoću svetlosnog mikroskopa. Kombinovani tretman poboljšava renalnu hemodinamiku, poremećenu usled ishemične akutne bubrežne slabosti. U ovom modelu bubrežne slabosti dolazi do pada klirensa kreatinina i uree, i povećanja lipidne peroksidacije u plazmi.Tretman Losartanom i Tempolom dovodi do značajnog povećanja klirensa kreatinina i uree. Lipidna peroksidacija je smanjena, a aktivnost glutation peroksidaze u eritrocitima je povećana nakon kombinovanog tretmana sa Losartanom i Tempolom. Takođe, ovakav kombinovan tretman smanjuje kortiko-medularnu nekrozu i tubularnu dilataciju u bubregu. Naši rezultati ukazuju na to da sinergizam Losartana i Tempola može imati povoljan efekat na krvni pritisak i bubrežnu funkciju tokom razvoja postishemične akutne bubrežne slabosti u eksperimentalnoj hipertenziji.

Introduction. The causes of acute tubulointerstitial nephritis can be grouped into four broad categories: medications, infections, immunologic diseases, or idiopathic processes. Here we report a 17-year-old female who developed acute kidney injury (AKI) due to granulomatous interstitial nephritis (GIN) associated with influenza A: H1N1 infection. Case Outline. The illness presented after two weeks of respiratory tract infection, skin rash and hypermenorrhea. On admission the patient was febrile, with bilateral pedal edema, macular skin rash, and auscultatory finding that suggested pneumonia. Laboratory investigations showed normocytic anemia, azotemia, hematuria and proteinuria. Renal ultrasound was normal. Antinuclear antibodies, antineutrophil cytoplasmic antibodies, lupus anticoagulant, antiphospholipid antibodies were negative with normal complement. Urine cultures including analysis for Mycobacterium tuberculosis were negative. The diagnosis of influenza A: H1N1 infection was made by positive serology. A kidney biopsy showed interstitial nephritis with peritubular granulomas. Glomeruli were normal. Staining for immunoglobulins A, M, G, and E was negative. The girl was treated with oseltamivir phosphate (Tamiflu; Genentech, Inc., South San Francisco, CA, USA) for five days, as well as with tapered prednisone after a starting dose of 2 mg/kg. The treatment resulted in a complete remission during two years of follow-up. Conclusion. We present a severe but reversible case of GIN and AKI associated with influenza A: H1N1 infection. Although a causal effect cannot be confirmed, this case suggests that influenza A: H1N1 should be considered in the differential diagnosis of GIN manifested with AKI in children. [Projekat Ministarstva nauke Republike Srbije, br. 175079]

Background. At early stages of kidney development, the neural cell adhesion molecule (NCAM) is highly expressed on cells of the metanephrogenic mesenchyme. During maturation of the fetal kidney, NCAM gradually disappears. So far, it has been widely accepted that NCAM in the adult kidney is only expressed by nerves, and not by other cell types. Methods. NCAM expression was analysed in human adult healthy and diseased kidneys by immunohistochemistry and western blot analysis. NCAMþ renal interstitial cells were further characterized by double immunofluorescent staining using antibodies against neurofilaments, a smooth muscle actin, vimentin, a5b1 integrin, CD68, CD11c, HLA-DR and the potential progenitor cell markers CD34, CD117, CD133, CD24, nestin and cadherin-11. Results. In adult human kidneys, NCAM expression is restricted to rare interstitial cells with dendritic morphology, which are neurofilament-negative and predominantly localized on the corticomedullary junction. They are also negative for fibroblast cell markers, but co-express the haematopoietic stem cell markers CD34 and CD133. The number of NCAMþ interstitial cells increased in the initial phases of interstitial fibrosis. Western blot analysis of renal tissues with incipient interstitial fibrosis tissues showed the expression of the 140 kDa NCAM isoform. Conclusions. These data indicate that a rare subpopulation of NCAMþ interstitial cells could represent renal progenitors, and that NCAMþ interstitial cells can participate in the initial phase of interstitial fibrosis.

Many studies demonstrated that angiotensin 2 type 1 receptor (AT1R) blockade accelerates renal recovery in post-ischaemic kidney but there are many controversies related to its net effect on kidney structure and function. During the past years, our research group was trying to define the pathophysiological significance of the renin-angiotensin system on post-ischemic acute renal failure (ARF) development in normotensive Wistar as well as hypertensive rats (SHR). This review mostly summarizes our experience in that field. Our previous studies in normotensive rats revealed that AT1R blockade, except slightly renal vascular resistance improvement, had no other obvious beneficial effects, and therefore implies angiotensin 2 (Ang-2) overexpression as non-dominant on kidney reperfusion injuries development. Similarly it was observed in Wistar rats with induced mild (L-NAME, 3 mg/kg b.w.) nitric oxide (NO) deficiency. Expectably, in strong induced (L-NAME, 10 mg/kg b.w.) NO deficiency associated with ARF, massive tubular injuries indicate harmful effects of AT1R blockade, implying strongly disturbed glomerular filtration and suggesting special precaution related to AT1R blockers usage. Opposite to previous, by our opinion, AT1R antagonism promises new advance in treatment of essentially hypertensive subjects who develop ARF. Increased glomerular filtration, diminished oxidative stress, and most importantly improved tubular structure in postishemic SHR treated with AT1R blocker losartan, implicate Ang-2 over production as potently agent in the kidney ischemic injury, partly trough generation of reactive oxygen species. These data contribute understanding the pathogenesis of this devastating illness in hypertensive surroundings.

We reviewed the clinical, histological and serological parameters of microscopic polyangiitis (MPA) associated with antineutrophil cytoplasmic antibodies (ANCA) specific to myeloperoxidase (MPO). Six girls and one boy aged 12.0+/-2.6 years (7-15 years) met the following inclusion criteria: (1) clinical manifestations of systemic small vessel involvement; (2) histological demonstration of pauci-immune necrotizing glomerulonephritis; and (3) serological findings of increased concentration of MPO-ANCA by ELISA test. The main clinical manifestations were: influenza-like symptoms (100%), hematuria/proteinuria (100%), purpura (100%), pulmonary-renal syndrome (57%), acute renal failure (ARF) (29%), ischemic cerebral insults (29%), and necrotizing vasculitis of the skin (29%). All patients underwent renal biopsy examined by immunohistochemistry with expression of alpha-smooth muscle actin (alpha SMA) in glomerular and interstitial spaces. Patients were followed from 6 months to 5.5 years (35.4+/- 23.2 months). None of the patients died. Two of seven children who had ARF progressed to end stage renal disease; one developed chronic renal failure, and four normalized renal function. ARF and central nervous system involvement at presentation were parameters of poor renal outcome. A high score of fibro-cellular glomerular crescents was associated with worse prognosis. Early treatment enables a favorable prognosis of MPO-ANCA-associated MPA in children.

The absence of basal cell layer of prostatic acini containing high-molecular cytokeratin, which is immunohistochemically detected by monoclonal antibody 34?E12, is an essential diagnostic characteristic of prostatic cancer. The absence of im munohistochemical reaction in 3 or more pseudo glandular structures of prostatic tissue indicates malignant process. The percentage of immunohistochemically completely negative glandular structures was determined by semiquantitative measurement in tissue specimens obtained by TRUS biopsy of the prostate, and it was correlated with serum PSA concentration and Gleason score. The increase of percentage of glandular prostatic formations completely negative to high-molecular cytokeratin detected by 34?E12 led to simultaneous rise of mean value of Gleason prostatic cancer score (p

Rare neural cell adhesion molecule (NCAM) positive cells have been previously described within the normal human adult kidney interstitium, speculating that they could increase in the interstitium with incipient interstitial renal fibrosis (IRF). In the present study, among 93 biopsy samples of various kidney diseases, NCAM+ interstitial cells were detected in 62.4% cases. An increased number of NCAM+ cells was significantly observed only in incipient IRF compared to normal renal tissues and advanced IRF stages (p

The α-defensins human neutrophil peptides (HNPs)-1, -2, and -3 have been described as cytotoxic peptides with restricted expression in neutrophils and in some lymphocytes. In this study we report that HNPs-1, -2, and -3 are also expressed in renal cell carcinomas (RCCs). Several RCC lines were found to express mRNA as well as the specific peptides of HNP-1, -2, and -3 demonstrated by reverse transcriptase-polymerase chain reaction, mass spectrometric, and flow cytometric analyses. At physiological concentrations HNPs-1, -2, and -3 stimulated cell proliferation of selected RCC lines in vitro but at high concentrations were cytotoxic for all RCC lines tested. As in RCC lines, α-defensins were also detected in vivo in malignant epithelial cells of 31 RCC tissues in addition to their expected presence in neutrophils. In most RCC cases randomly, patchy immunostaining of α-defensins on epithelial cells surrounding neutrophils was seen, but in six tumors of higher grade malignancy all tumor cells were diffusely stained. Cellular necrosis observed in RCC tissues in association with extensive patches of HNP-1, -2, and -3, seemed to be related to high concentrations of α-defensins. The in vitro and in vivo findings suggest that α-defensins are frequent peptide constituents of malignant epithelial cells in RCC with a possible direct influence on tumor proliferation.

Several reports have documented various forms of glomerular diseases in adults with myelodysplastic syndromes (MDS), but similar reports in children are lacking. We describe two children with MDS-associated with steroid-responsive nephrotic syndrome (NS). Patient 1, who had MDS with myelofibrosis, presented also hepatosplenomegaly, pancytopenia, chronic hepatitis, moderate proteinuria, hypocomplementemia and elevated ANA titer. During initial prednisone treatment proteinuria markedly diminished and partial but transient haematological improvement occurred. Relapse subsequently occurred that was manifested by overt NS and pancytopenia. High doses of prednisolone led to remission of the renal disease but haematological remission did not occur. Persisting pancytopenia and repeated infections terminated in sepsis, two years after the onset of MDS. Patient 2, who had refractory anemia with clonal monosomy 19, manifested bowel disease, hepatospleno- megaly, anaemia and non-organic specific autoantibodies. Prednisone led to both clinical and haematological remission. Haematologic disease relapsed 12 months later, when nephrotic-range proteinuria, haematuria and mild azotaemia were also found. Corticosteroid treatment led to long-lasting renal and haematologic remission, maintained by a small dosage of prednisone. In both patients renal biopsy findings were consistent with those seen in idiopathic NS. A Medline search disclosed 16 cases of glomerulopathy in the course of MDS in adult patients. Clinical features included NS, usually accompanied by renal insufficiency with either acute, chronic, or rapidly progressive glomerulonephritis. On biopsy, membranous nephropathy, crescentic or mesangial proliferative glomerulonephritis and AL amyloidosis, were found. We conclude: (1) that glomerular disease may be present and should be searched for in patients with MDS; (2) that MDS can be added to the list of rare conditions associated with corticosteroid-responsive NS in children.

Acute kidney injury (AKI) is associated with significant morbidity and mortality in hypertensive surroundings. We investigated superoxide radical molecules influence on systemic haemodynamic and kidney function in spontaneously hypertensive rats (SHR) with induced postischemic AKI. Experiment was performed in anesthetized adult male SHR. The right kidney was removed, and left renal artery was subjected to ischemia by clamping for 40 minutes. The treated group received synthetic superoxide dismutase mimetic TEMPOL in the femoral vein 5 minutes before, during, and 175 minutes after the period of reperfusion, while the control AKI group received the vehicle via the same route. All parameters were measured 24 h after renal reperfusion. TEMPOL treatment significantly decreased mean arterial pressure and total peripheral resistanceP<0.05compared to AKI control. It also increased cardiac output and catalase activityP<0.05. Lipid peroxidation and renal vascular resistance were decreased in TEMPOLP<0.05. Plasma creatinine and kidney morphological parameters were unchanged among TEMPOL treated and control groups. Our study shows that superoxide radicals participate in haemodynamic control, but acute superoxide scavenging is ineffective in glomerular and tubular improvement, probably due to hypertension-induced strong endothelial dysfunction which neutralizes beneficial effects ofO2−scavenging.

Several reports have documented various forms of glomerular diseases in adults with myelodysplastic syndromes (MDS), but similar reports in children are lacking. We describe two children with MDS-associated steroid-responsive nephrotic syndrome (NS). Patient 1, who had MDS with myelofibrosis, presented with hepatosplenomegaly, pancytopenia, chronic hepatitis, moderate proteinuria, hypocomplementemia and elevated ANA titer. During initial prednisone treatment proteinuria markedly diminished and partial but transient hematological improvement occurred. Relapse subsequently occurred that manifested by overt NS and pancytopenia. High doses of prednisolone led to remission of the renal disease, but hematological remission did not occur. Persisting pancytopenia and repeated infections terminated in sepsis, 2 years after the onset of the MDS. Patient 2, who had refractory anemia with clonal monosomy 19, presented with bowel disease, hepatosplenomegaly, anemia and non-organ-specific autoantibodies. Prednisone led to both clinical and hematological remission. The hematologic disease relapsed 12 months later, when nephrotic-range proteinuria, hematuria and mild azotemia were also found. Corticosteroid treatment led to long-lasting renal and hematologic remission, maintained by a small dosage of prednisone. In both patients, renal biopsy findings were consistent with those seen in idiopathic NS. A Medline search disclosed 16 cases of glomerulopathy in the course of MDS in adult patients. Clinical features included NS, usually accompanied by renal insufficiency with acute, chronic, or rapidly progressive glomerulonephritis. On biopsy, membranous nephropathy, crescentic or mesangial proliferative glomerulonephritis, and AL amyloidosis were found. We conclude: (1) that glomerular disease may be present and should be searched for in patients with MDS and (2) that MDS can be added to the list of rare conditions associated with corticosteroid-responsive NS in children.

Introduction. Primary kidney sarcoma, especially synovial sarcoma (SS), is a very rare neoplasm. Pre-operative signs and symptoms are very similar to renal cell carcinoma, therefore, the proper diagnosis is very difficult and usually made after nephrectomy. This is a case report of primary renal SS. Case Outline. A 38-year-old man presented with a history of fever and hematuria, and right flank pain 3 weeks ago. Abdominal computerized tomography revealed a heterogeneous well-marginated soft tissue mass arising in the lower part of the right kidney. Right nephrectomy was performed. A cystic tumor of 120x85 mm in size with soft solid growth, and with the extensive areas of hemorrhage and necrosis was seen on gross examination. Histopathology revealed a neoplasm composed of solid monomorphic sheets of spindle cells. Immunohistochemistry showed tumor cells strongly positive for BCL2, CD99, CD56 and vimentin, and focally positive for epithelial membrane antigen (EMA). The histological diagnosis of primary renal SS was based on morphology and immunohistochemistry. FISH analysis and RT-PCR was carried out on formalin-fixed paraffin-embedded tissue sections. The molecular analysis demonstrated translocation of SYT gene on chromosome 18 and SSX2 gene on chromosome X. The findings were consistent with diagnosis of SS. Conclusion. Our case shows that histopathological diagnosis of primary kidney SS, although difficult, is possible to be made on the basis of morphological and immunohistochemical analysis. However, this diagnosis should be corroborated by molecular techniques confirming SYT-SSX translocation on chromosome 18 and chromosome X. Here we present visceral monophasic SS with aggressive clinical course and poor outcome. [Projekat Ministarstva nauke Republike Srbije, br. OI 175047]

Ischemic acute renal failure (ARF) is a highly complex disorder involving renal vasoconstriction, filtration failure, tubular obstruction, tubular backleak and generation of reactive oxygen species. Due to this complexity, the aim of our study was to explore effects of Angiotensin II type 1 receptor (AT1R) blockade on kidney structure and function, as well as oxidative stress in spontaneously hypertensive rats (SHR) after renal ischemia reperfusion injury. Experiments were performed on anaesthetized adult male SHR in the model of ARF with 40 minutes clamping the left renal artery. The right kidney was removed and 40 minutes renal ischemia was performed. Experimental groups received AT1R antagonist (Losartan) or vehicle (saline) in the femoral vein 5 minutes before, during and 175 minutes after the period of ischemia. Biochemical parameters were measured and kidney specimens were collected 24 h after reperfusion. ARF significantly decreased creatinine and urea clearance, increased LDL and lipid peroxidation in plasma. Treatment with losartan induced a significant increase of creatinine and urea clearance, as well as HDL. Lipid peroxidation in plasma was decreased and catalase enzyme activity in erythrocytes was increased after losartan treatment. Losartan reduced cortico-medullary necrosis and tubular dilatation in the kidney. High expression of pro-apoptotic Bax protein in the injured kidney was downregulated after losartan treatment. Our results reveal that angiotensin II (via AT1R) mediates the most postischemic injuries in hypertensive kidney through oxidative stress enhancement. Therefore, blockade of AT1R may have beneficial effects in hypertensive patients who have developed ARF.

A high prevalence of chronic kidney disease among children with focal segmental glomerulosclerosis (FSGS) leads to a permanent quest for good predictors of kidney dysfunction. Thus, we carried out a retrospective cohort study in order to examine known clinical and morphological predictors of adverse outcome, as well as to investigate glomerular nestin expression as a potential new early predictor of kidney dysfunction in children with FSGS. Relationships between nestin expression and clinical and morphological findings were also investigated. Among 649 renal biopsy samples, obtained from two children’s hospitals, FSGS was diagnosed in 60 children. Thirty-eight patients, who met the criteria for this study, were followed up for 9.0 ± 5.2 years. Using Kaplan–Meier and Cox’s regression analysis, potential clinical and morphological predictors were applied in two models of prediction: after disease onset and after the biopsy. The present study revealed the following significant predictors of kidney dysfunction: patients’ ages at disease onset, as well as age at biopsy, resistance to corticosteroid treatment, serum creatinine level, urine protein/creatinine ratio, vascular involvement, tubular atrophy, interstitial fibrosis, and decreased glomerular nestin expression. The most important finding of our study is that nestin can be used as a potential new early morphological predictor of kidney dysfunction in childhood onset of FSGS, since nestin has been obviously decreased in both sclerotic and normal glomeruli seen by light microscopy.

Pax-2 transcriptional factor is expressed during kidney development and could re-express in renal tumors. The aim of this study was to examine Pax-2 expression in different types of renal cell carcinoma (RCC) in order to see whether it is good immunohistochemical marker. Method: We analyzed 48 different renal tumours stained with Pax-2 antibody. Pax-2 positive reaction was noticed in nucleus or cytoplasm. Expression of this antigen in tumours tissue was correlated with tumour stage and nuclear grade. Pax-2 expression between different histological RCC types was analyzed by X2 test and Fishers test for two in depended samples. Results: Pax-2 is expressed by a high percentage of renal tumors regardless of histologic type. Significant difference of Pax-2 expression between oncocytomas and chromofobe RCC was found. Conclusion: Nuclear expression of Pax-2 is useful diagnostic kidney tumour marker. Pax-2 showed stronger expression in lower malignancy kidney tumours and in oncocytomas, than in high grade RCC like in those with sarcomatoid differentiation.

Balkan endemic nephropathy (BEN) is interesting renal disease, because of its unique clinical, epidemiological and morphological characteristics: intensive interstitial fibrosis and tubular atrophy without any inflammation. In the present paper we evaluate the incidence of BEN from the morphological point of view for the last decade. Therefore we analyzed material obtained from autopsies, kidney biopsies and nephrectomy due to upper urothelial cancer (UUC) from the patients which were divided into two groups: those with permanent residence in BEN areas and those from nonendemic areas. At the Institute of Pathology, University of Belgrade for the last 15 years we had only 1 autopsy due to BEN out of 6,825. More than 30 years ago there were over 50 autopsy cases of BEN at the same institute. For the last decade we had only 2 kidney biopsies suspected for BEN out of 2,182, but morphologically not confirmed as BEN. However, previously we had over 40 kidney biopsies diagnosed as early or late stage of BEN. At the Clinical Center of Serbia 180 nephrectomies were performed due to UUC. The incidence of UUC for the last five years in BEN regions has significantly decreased, whereas at the same time in non-BEN regions it has remained on the same level. There was no morphological difference of the renal tissue adjacent to tumor between patients from BEN and non-BEN regions. According to our study based on routine pathological work, we could clearly conclude that BEN today is more clinical and epidemiological than a morphological entity.

Background: This study was conducted to retrospec- tively investigate the indications for renal biopsy in native kidneys and to analyze pathological findings in the last 10 years in a single tertiary pediatric hospital in Serbia. Methods: All patients who underwent renal biopsy at our hospital between 2001 and 2010 were included in the present study. Renal biopsy was performed un- der fluoroscopy with a biopsy gun. All renal biopsies were studied under light and immunofluorescent mi- croscopy, while electron microscopy was rarely per- formed. Results: The study group included 150 patients (56% female) who underwent 158 percutaneous native kid- ney biopsies. Median age was 11.5 years (range 0.2-20 years). The most frequent indications for renal biop- sy were nephrotic syndrome (32.9%), asymptomatic hematuria (23.4%), urinary abnormalities in systemic diseases (15.8%) and proteinuria (11.4%). Primary glo- merulonephritis (GN) was the most common finding (57.4%), followed by secondary GN (15.5%) and tubu- lointerstitial diseases (4.5%). According to histopatho- logical diagnosis, the most common causes of primary GN were focal segmental glomerulosclerosis (20.9%), mesangioproliferative GN (14.6%), IgA nephropathy (8.9%) and minimal change disease (13%). Lupus ne- phritis (6%) and Henoch-Schonlein nephritis (4%) were the most common secondary glomerular diseases. Conclusions: The epidemiology of glomerular disea- se in our single-center report is similar to that in data from adjacent Croatia and Greece. Focal segmental glomerulosclerosis was the dominant histopathologi- cal finding, followed by mesangioproliferative GN and IgA nephropathy.

Balkan endemic nephropathy (BEN) is interesting renal disease, because of its unique clinical, epidemiological and morphological characteristics: intensive interstitial fibrosis and tubular atrophy without any inflammation. In the present paper we evaluate the incidence of BEN from the morphological point of view for the last decade. Therefore we analyzed material obtained from autopsies, kidney biopsies and nephrectomy due to upper urothelial cancer (UUC) from the patients which were divided into two groups: those with permanent residence in BEN areas and those from non-endemic areas. At the Institute of Pathology, University of Belgrade for the last 15 years we had only 1 autopsy due to BEN out of 6,825. More than 30 years ago there were over 50 autopsy cases of BEN at the same institute. For the last decade we had only 2 kidney biopsies suspected for BEN out of 2,182, but morphologically not confirmed as BEN. However, previously we had over 40 kidney biopsies diagnosed as early or late stage of BEN. At the Clinical Center of Serbia 180 nephrectomies were performed due to UUC. The incidence of UUC for the last five years in BEN regions has significantly decreased, whereas at the same time in non-BEN regions it has remained on the same level. There was no morphological difference of the renal tissue adjacent to tumor between patients from BEN and non-BEN regions. According to our study based on routine pathological work, we could clearly conclude that BEN today is more clinical and epidemiological than a morphological entity.

Because adrenergic contractions can contribute to the development of life-threatening spasm of coronary artery bypass graft, this study was performed to investigate the effect of adenosine 3-phosphate (ATP)-sensitive K+ channel (KATP) opener P1075 on contractions of isolated human saphenous vein (HSV) and human internal mammary artery (HIMA). Phasic contractions were evoked by electric field stimulation (20 Hz) and noradrenaline. The sustained contractions were evoked by phenylephrine. The presence of pore-forming Kir6.1 and Kir6.2 subunits of the KATP channels in the HIMA and only Kir6.2 in the HSV was confirmed immunomorphologically. P1075 inhibited in the HSV only, the electrical field stimulation contractions more strongly than noradrenaline contractions. In addition, the phenylephrine contractions of HSV were more sensitive to P1075 in comparison to those of HIMA. Glibenclamide, a KATP channel blocker antagonized the vasodilatation produced by P1075 in both grafts differently, because its effect was more prominent on the P1075-induced inhibition of contractions of HSV than of HIMA. We conclude that P1075 has a vasorelaxant effect and inhibited adrenergic contractions of the tested grafts. This effect is graft and vasoconstrictor selective and seems to be mediated by Kir6.1- and/or Kir6.2-containing KATP channels. Thus, P1075 can be considered as a potential drug in the prevention of graft spasm.

In order to discover an agent that can prevent spasm of the human radial artery, the aim of our study was to evaluate the effect of the K(+) channel opener, pinacidil, on contractions in the radial artery. Contractions of the radial artery were evoked by exogenously applied noradrenaline or by electrical field stimulation (EFS, 20Hz, neurogenic). Pinacidil induced concentration-dependent inhibition of both EFS- and noradrenaline-evoked contractions of the radial artery. Glibenclamide, a selective blocker of ATP-sensitive K(+) channels (Kir6.x containing subunit) antagonized in the same manner the pinacidil-induced inhibition of neurogenic contractions and contractions evoked by exogenous noradrenaline. The inhibition of pinacidil relaxation by tetraethylammonium (TEA), a blocker of Ca-sensitive K(+) (K(Ca)) channels, was more pronounced in EFS-contracted preparations. A blocker of voltage-sensitive K(+) (K(V)) channels, 4-aminopyridine (4-AP), inhibited pinacidil relaxation only in EFS-contracted preparations. In order to test the presence of different K(+) channels, immunohistochemistry of K(+) channels expression in the radial artery was performed. The vascular wall of the human radial artery showed variable positivity with the following applied antibodies: Kv1.2, Kv1.3, Kir6.1, and K(Ca)1.1. The antibodies against Kv1.6, Kv2.1, and Kir6.2 channel subunits were completely negative. These results suggest that the inhibitory effect of pinacidil on contractions of the human radial artery might be postsynaptic and associated with opening of smooth muscle Kir6.1-containing K(ATP) channels. TEA- and 4-AP-sensitive K(+) channels may also contribute to pinacidil effect in the human radial artery.

The aim of this study was to evaluate KCNQ1 K+ channel expression in the frog kidney of Rana esculenta. KCNQ1 K+ channel, also known as KvLQT1, is the pore forming α-subunit of the IKs K+ channel, a delayed rectifier voltage-gated K+ channel, which has an important role in water and salt transport in the kidney and gastrointestinal tract. The expression of KCNQ1 K+ channel along tubular epithelium differs from species to species. In the present study the expression of KCNQ1 K+ channel in the frog kidney has been demonstrated by immunohistochemistry. The presence of KCNQ1 K+ channel was demonstrated in the epithelial cells of distal convoluted tubule and collecting duct. However, the pattern of expression of KCNQ1 K+ channel differs between distal convoluted tubules and collecting duct. All epithelial cells of distal convoluted tubules revealed basolateral expression of KCNQ1 K+ channel. On the contrary, only the single cells of collecting duct, probably intercalated cells, showed diffuse cell surface staining with antibodies against KCNQ1 K+ channel. These findings suggest that KCNQ1 K+ channel has cell-specific roles in renal potassium ion transport.

Immunophenotyping of infiltrating glomerular and interstitial mononuclear leukocytes performed in renal tissues of 15 patients with focal segmental glomerulosclerosis (FSGS) was compared to 15 normal kidneys in order to investigate a possible role for cell-mediated immunity (CMI) in FSGS. In addition, distribution of HLA class II (-DQ, -DR, -DP and -DY) antigens and of the intercellular adhesion molecule 1 (ICAM-1) as well as the expression of well-defined renal antigens along the human nephron was analyzed. In comparison to normal kidneys, a reduction in HLA class II antigens of ICAM-1 and of renal antigens defined by the monoclonal antibodies TN8-TN10 was observed in sclerotic glomeruli. Furthermore, an increased number of T lymphocytes was found in glomeruli of FSGS with slight predominance of the CD8+ subset. Interstitial inflammation was present in all FSGS cases except 1 with T lymphocytes and monocytes/macrophages constituting the predominant infiltrating cell types. In contrast to the glomerular T cells, the number of interstitial CD4+ cells was greater than the number of CD8+ cells in almost all cases. As a sign of activation, most interstitial inflammatory cells carried HLA class II antigens and some of them also expressed ICAM-1. Proximal tubular epithelial cells often presented an abnormal expression of HLA-DQ and HLA-DP antigens associated with aberrant expression of ICAM-1 and TN8. The number of interstitial mononuclear leukocytes was correlated to serum creatinine levels at the time of renal biopsy. The present results provide further support for the involvement of CMI in the pathogenesis of FSGS.

Aims Primary bladder non-Hodgkin lymphoma (PBNHL) is very rare, especially as extranodal B-small lymphocytic lymphoma (B-SLL). Also, late isolated renal manifestation of PBNHL is extremely unusual. We report a very rare type of extranodal B-SLL of bladder wall with extremely unusual late isolated renal involvement, clinically manifested by nephrotic syndrome and incipient renal failure. A case report A 56-year-old woman was presented with a solitary tumor of bladder wall, with history of dysuria and night sweating. A transvaginal needle biopsy of the tumor was performed, and diagnosis of primary extranodal B-SLL was made in the absence of bone marrow, lymph node, or blood involvement. She was treated with chemotherapy until the achievement of complete remission. Nine years later, she developed nephrotic syndrome. The renal biopsy revealed parenchymal lymphoma’s involvement associated with glomerular lesion. Immunohistochemical analysis confirmed the same imunophenotype of lymphoma cells like in bladder wall nine years ago. Restaging procedure showed no evidence of disease elsewhere. Conclusion To our knowledge, it is the first case of association of very rare primary bladder B-SLL with late isolated renal involvement.

Background. Acute renal failure (ARF) is a devastating illness, especially when it occurs in various conditions with impaired nitric oxide (NO) synthesis, such as arterial hypertension, heart failure and some renal diseases. We have directed our investigations to effects of both angiotensin II (AII) and endothelin (ET) receptor blockade associated with mild or strong NO deficiency on haemodynamic, biochemical and morphological parameters in experimental post-ischaemic ARF. Methods. In this study, we used bosentan (dual, ETA/ETB-receptor antagonist), losartan (non-peptide, competitive antagonist of type I AII receptor), and NG-nitro-L-arginine methyl ester (L-NAME), inhibitor of NO synthesis. Experiments were performed in anaesthetized, adult male Wistar rats. The right kidney was removed and the renal ischaemia was performed by clamping the left renal artery for 45 min. Experimental groups received receptor antagonists (bosentan or losartan) or vehicle (saline) in the femoral vein 20 min before, during and 20 min after the period of ischaemia. L-NAME was given as i.v. bolus before each antagonist infusion. All parameters were measured 24 h after reperfusion. Results. Our results showed that strong NO blockade overcame effects of both ET and AII receptor blockade in experimental post-ischaemic ARF. In addition, the AII receptor blockade had a harmful effect on this condition, probably due to disturbed autoregulatory renal function. On the other hand, ET and AII receptor blockade in mild NO blockade associated with reperfusion injury, improves the most haemodynamic, biochemical and morphological parameters. Conclusions. We concluded that experimental post-ischaemic ARF is neither AII nor ET mediated in case of strong NO blockade, but, in more realistic conditions of mild NO deficiency, these peptides represent significant players whose receptor blockade expressed relevant therapeutic potential.

Resveratrol, a stilbene polyphenol found in grapes and red wine, produces vasorelaxation in both endothelium-dependent and endothelium-independent manners. The mechanisms by which resveratrol causes vasodilatation are uncertain. The aim of this study was to investigate the mechanism(s) of endothelium-independent resveratrol-induced vasorelaxation in human internal mammary artery (HIMA) obtained from male patients undergoing coronary artery bypass surgery and to clarify the contribution of different K+ channel subtypes in resveratrol action in this blood vessel. HIMA rings without endothelium were precontracted with phenylephrine. Resveratrol induced a concentration-dependent relaxation of the HIMA. A highly selective blocker of ATP-sensitive K+ channels, glibenclamide, as well as nonselective blockers of Ca2+-sensitive K+ channels, tetraethylammonium and charybdotoxin, did not block resveratrol-induced relaxation of HIMA rings. 4-Aminopyridine (4-AP), non selective blocker of voltage-gated K+ (KV) channels, and margatoxin that inhibits KV1.2, KV1.3, and KV1.6 channels abolished relaxation of HIMA rings induced by resveratrol. In conclusion, we have shown that resveratrol potently relaxed HIMA rings with denuded endothelium. It seems that 4-AP- and margatoxin-sensitive K+ channels located in smooth muscle of HIMA mediated this relaxation. Keywords:: resveratrol, vasorelaxation, human internal mammary artery, K+ channel

Background The relative roles of endothelin (ET)-1 and angiotensin (ANG) II in post-ischaemic acute renal failure (ARF) have not been fully established so far. With the aim of contributing to this goal, we assessed in this study the effect of ANG II and ET-1 blockade on the course of post-ischaemic-ARF. Methods Anaesthetized Wistar rats received i.v. either bosentan (a dual ET receptor antagonist; 10 mg/kg body weight) or losartan [ANG II type 1 (AT(1)) receptor antagonist; 5 or 10 mg/kg body weight] or both, 20 min before, during and 20 min after ischaemia. Rats in the control group received the vehicle via the same route. Survival and renal function were monitored up to 8 days after the ischaemic challenge, while haemodynamic parameters were measured 24 h after ARF. Results Our results demonstrate that bosentan treatment has a more beneficial effect on experimental ARF than losartan. The survival rate was remarkably higher in bosentan-treated rats than in both rat groups treated with losartan. In the ARF group treated with bosentan, renal blood flow (RBF) was increased by 129% in comparison with the untreated ARF group, whereas in the losartan-treated ARF groups, RBF was only approximately 35 or 38% higher than in control ARF rats. The glomerular filtration rate was markedly higher in bosentan-treated rats than in all other ARF groups on the first and second day after ischaemia. Tubular cell injury was less severe in bosentan-treated rats than in the control ARF rats, but in losartan-treated groups it was similar to that in the ARF group. Concurrent blockade of both ET and AT(1) receptors did not improve ARF because this treatment induced a marked decrease in blood pressure. Conclusions These results suggest that ET-1 blockade is more efficient in improving the early course of post-ischaemic renal injury than ANG II inhibition, and that blockade of ET-1 might be effective in prophylaxis of ischaemic ARF.

The alpha-defensins human neutrophil peptides (HNPs)-1, -2, and -3 have been described as cytotoxic peptides with restricted expression in neutrophils and in some lymphocytes. In this study we report that HNPs-1, -2, and -3 are also expressed in renal cell carcinomas (RCCs). Several RCC lines were found to express mRNA as well as the specific peptides of HNP-1, -2, and -3 demonstrated by reverse transcriptase-polymerase chain reaction, mass spectrometric, and flow cytometric analyses. At physiological concentrations HNPs-1, -2, and -3 stimulated cell proliferation of selected RCC lines in vitro but at high concentrations were cytotoxic for all RCC lines tested. As in RCC lines, alpha-defensins were also detected in vivo in malignant epithelial cells of 31 RCC tissues in addition to their expected presence in neutrophils. In most RCC cases randomly, patchy immunostaining of alpha-defensins on epithelial cells surrounding neutrophils was seen, but in six tumors of higher grade malignancy all tumor cells were diffusely stained. Cellular necrosis observed in RCC tissues in association with extensive patches of HNP-1, -2, and -3, seemed to be related to high concentrations of alpha-defensins. The in vitro and in vivo findings suggest that alpha-defensins are frequent peptide constituents of malignant epithelial cells in RCC with a possible direct influence on tumor proliferation.

The main goal of this study was to examine the efficacy of endothelin (ET) receptor blockade in the course of experimental postischaemic acute renal failure (ARF). Experiments were performed on male adult Wistar rats. The right kidney was removed before renal ischaemia (by clamping the left renal artery for 45 minutes). The experimental groups received either bosentan (ETA/ETB-receptor antagonist; 10mg/kg/b.m) or vehicle (saline) in the femoral vein 20 minutes before, during and 20 minutes after ischaemia. All parameters were measured 24 hours after reperfusion. The obtained results clearly demonstrate that bosentan yields beneficial effect on ARF. Bosentan improves both renal haemodynamic and functional parameters after ARF, while lesions of tubular epithelial cells, the principal targets of injury in ARF are less serious in bosentan-treated rats than in the control ARF rats. This strongly suggests that endothelins have an important role in the development of ischaemia/'reperfusion injury and contributes to the promotion of bosentan in future clinical practice. Uticaji blokade receptora endotelinskih peptida na tok postishemične eksperimentalne akutne bubrežne insuficijencije (ABI), predstavljali su glavni cilj naših istraživanja. Eksperimenti su izvođeni na odraslim pacovima Wistar soja. Urađena je netrektomija desnog bubrega, a leva bubrežna arterija je klemovana u trajanju od 45 minuta. Eksperimentalne grupe su prekofemoralne vene primale Hi bpsentan (antagonist ETA/ETB-receptora) Hi fiziološki rastvor, kontinuirano, 20 minuta pre, tokom i 20 minuta posle perioda ishemije. Svi parametri su mereni 24 časa nakon perioda ishemije. Dobijeni rezultati jasno pokazuju da bozentan iskazuje povoljne uticaje na tok ABI. Bozentan poboljšava bubrežne hemodinamske i funkcionalne parametre, a lezije epitelnih ćelija tubula (glavnih mesta oštećenja u ABI), su manje izražene kod pacova tretiranih bosentanom, negp kod kontrolnih životinja sa ABI. Sve to navodi na zaključak da endotelini imaju uticaja u razvoju ishemično/reperfuzionih oštećenja u ABI i da bosentan poseduje potencijal za primenu u kliničkoj praksi.