Gordana Basta-Jovanovic

Renal biopsy registry from a single centre in Serbia: 20 years of experience

BACKGROUND There is not enough epidemiologic data of biopsy proven renal diseases. This is the first report of clinicopathologic correlations over a period of 20 years from central Balkan country-Serbia. METHODS A retrospective review of reports of 2 362 native renal biopsies performed on patients at the leading nephrology unit in Serbia from 1987 to 2006 was undertaken. Patients were divided in two groups according to age: younger (<60 years old) and older (>or=60 years old). RESULTS The annual incidence of renal biopsies increased from 3.9 p.m.p./year in 1987 to 12.5 p.m.p/year in 2006. The most common clinical syndrome as an indication for renal biopsy was nephrotic syndrome (NS) (53.6%). Membranous nephropathy was the most frequent cause of NS (21.6%). Primary glomerulonephritis (PGN) accounted for about two thirds of all performed biopsies. Non-IgA mesangioproliferative GN was the most frequent primary GN accounting for almost 25% of all PGN in our whole population, while the prevalence of IgA nephropathy was only 12%. Lupus nephritis was the most frequent secondary glomerulonephritis (75.6%). CONCLUSIONS This report represents epidemiological overview on biopsy proven renal disease coming from one specific Balkan country, which was under economic sanctions for almost half the studied period. We are hoping that this register will be the basis for developing not only a national register but also a register that will encompass all Balkan countries.

Gray level co-occurrence matrix texture analysis of germinal center light zone lymphocyte nuclei: physiology viewpoint with focus on apoptosis.

In our study we investigated the relationship between conventional morphometric indicators of nuclear size and shape (area and circularity) and the parameters of gray level co-occurrence matrix texture analysis (entropy, homogeneity, and angular second moment) in cells committed to apoptosis. A total of 432 lymphocyte nuclei images from the spleen germinal center light zones (cells in early stages of apoptosis) were obtained from eight healthy male guinea pigs previously immunized with sheep red blood cells (antigen). For each nucleus, area, circularity, entropy, homogeneity, and angular second moment were determined. All measured parameters of gray level co-occurrence matrix (GLCM) were significantly correlated with morphometric indicators of nuclear size and shape. The strongest correlation was observed between GLCM homogeneity and nuclear area (p < 0.0001, r(s) = 0.61). Angular second moment values were also highly significantly correlated with nuclear area (r(s)= 0.39, p < 0.0001). These results indicate that the GLCM method may be a powerful tool in evaluation of ultrastructural nuclear changes during early stages of the apoptotic process.

Complexity reduction of chromatin architecture in macula densa cells during mouse postnatal development.

To determine whether complexity of chromatin structure in kidney macula densa cells (MDC) decreases during postnatal development in mice.

Effects of Rapamycin on Active Heymann Nephritis

Background/Aim: The effects of rapamycin (RAPA) were examined in active Heymann nephritis (HN), an experimental model of human membranous nephropathy (MN). Current opinion on the therapy of MN is controversial, and medications used for its treatment have not yielded the expected results. Methods: In a two-part study, we examined the effects of RAPA (1.5 mg/kg/day) during the induction phase of HN and on the evolving disease. In both parts, control groups of immunized rats not treated with RAPA and control groups of unimmunized rats were observed and sacrificed concurrently with the treated groups. Results: During the induction phase no significant changes in proteinuria were observed in the group treated with RAPA, in comparison to those in the untreated group (p < 0.001). During the evolving disease RAPA significantly lowered proteinuria (p < 0.001). The characteristic pathohistologic changes and IgG depositions along the glomerular basement membrane were considerably diminished, and infiltration of CD8+ cells completely prevented. Conclusion: RAPA demonstrated beneficial effects on disease progression, given either in the induction phase or during evolving HN. It would be desirable to investigate the effect of RAPA on patients with MN.

Renal involvement in primary Sjogren syndrome of childhood: case report and literature review

Renal tubular acidosis (RTA) is common in adults with primary Sjogren syndrome (pSS) but to date this condition has only been identified in 12 pediatric cases of pSS. Here we present the case of a 13-year-old, otherwise asymptomatic girl in whom the search for the etiology of incidentally found nephrocalcinosis led to diagnosis of distal RTA and nephrogenic diabetes insipidus secondary to SS-associated tubulointerstitial nephritis. Immunosupressive treatment and alkali/electrolyte supplementation resulted in stable renal function over the 6-year follow-up. A review of the literature focuses on two aspects of pSS: (1) the difficulties in diagnosing pSS in childhood and (2) clinical–pathological features, treatment and outcome of renal tubulointerstitial disease in childhood pSS. SS should be considered in older children, particularly females with otherwise unexplained RTA. A careful search for other renal dysfunctions is necessary, and renal biopsy may be of value in assessing the extent of renal damage and the need for immunomodulatory therapy.

Age-related reduction of structural complexity in spleen hematopoietic tissue architecture in mice.

The effects of aging on structural complexity in hematopoietic tissue are unknown. In this work, in a mouse experimental model, we report the age-related reduction of spleen hematopoietic tissue (SHT) complexity. Spleen tissue was obtained from the total of 64 male Swiss albino mice divided into 8 age groups: newborns (0 days old), 10 days, 20 days, 30 days, 120 days, 210 days, 300 and 390 days old. SHT was stained using conventional hematoxylin/eosin, and DNA-binding toluidine blue dyes. Fractal dimension as an indicator of cellular complexity, and lacunarity as indicator of tissue heterogeneity were determined based on the binarized SHT micrographs. Results indicate that fractal dimension of mice spleen hematopoietic tissue decreases with age, while lacunarity increases. These changes/trends have been detected in SHT stained both with toluidine blue and conventional hematoxylin/eosin. Fractal dimension was negatively correlated with lacunarity. The detected reduction in complexity suggests that age-related structural changes are present in mouse SHT both in general tissue architecture and progenitor cell DNA.

Cyclosporine versus azathioprine therapy in high-risk idiopathic membranous nephropathy patients: A 3-year prospective study.

There is no consensus regarding the modality of therapy for idiopathic membranous nephropathy (IMN), especially for patients who did not react to treatment with cytotoxic drugs. This study followed prospectively for 3-year IMN patients who did not react to Ponticelli protocol comparing effects of 2-year course of cyclosporine (CsA) with azathioprine (Aza) treatment both with small doses of prednisolone. Twenty-three patients were randomly assigned to receive either cyclosporine at 3mg/kg per day (10 patients) or azathioprine at 1.5 to 2mg/kg (13 patients). Both groups were comparable regarding age, sex and renal function, except for proteinuria, which was significantly greater in CsA group (P=0.003). Similar rate of remission of nephrotic syndrome (NS) have been noted at the end of treatment (80% CsA versus 93% Aza). During last year, follow-up relapses of NS were more frequent in Aza group (5 versus 1). A fall in proteinuria was recorded in both groups during treatment, but it rose significantly in Aza group (1.5g/day versus 3.1g/day, P=0.04) and remained unchanged in CsA group (3.9g/day versus 4.1g/day) after treatment cessation. Renal function deteriorated in Aza group (sCr 120.5 versus 269.8μmol/L; P<0.01) and was stable in CsA group. In conclusion, CsA and steroids may be a very important option in the management of high-risk IMN patients. Long-term treatment is necessary for achievement of full therapeutic effect. Treatment with Aza did not have long-term benefits particularly regarding renal function preservation.

Acute Pretreatment with Chloroquine Attenuates Renal I/R Injury in Rats

Background Acute kidney injury (AKI) still remains an unresolved problem in pharmacotherapy and renal inflammation is a major factor in its development. Chloroquine, a well-known antimalarial drug, posses pleitropic effects as well: antiinflammatory, anticoagulant and vascular actions. The effects of chloroquine on renal function may involve significant increase in urine flow rate, glomerular filtration rate and sodium excretion, as well as stimulation of nitric oxide synthase. However, its role in experimental models of renal I/R injury is unknown. We aimed to analyze the acute effects of a single-dose intravenous chloroquine administered at three different times in the experimental model of I/R injury in rat. Methods Rats were subjected to bilateral renal ischemia (45 min) followed by reperfusion with saline lasting 4 hours. Chloroquine was administered in doses of 0.3 mg/kg i.v. and 3 mg/kg i.v. 30 min before ischemia, 30 min before reperfusion and 5 min before reperfusion. Selected a hemodynamic, biochemical and morphological parameters were followed in the Sham-operated animals and rats subjected to I/R injury and pretreated with saline or chloroquine. Results Chloroquine (0.3 and 3 mg/kg, i.v.) protected the I/R injured kidney in an U-shaped manner. Both doses were protective regarding biochemical and histological markers of the I/R injury (serum urea, creatinine and fractional excretion of sodium, as well as total histological score, tubular necrosis score and KIM-1 staining score) (P<0.05 vs. corresponding controls, i.e. rats subjected to I/R injury and treated with saline only). The protective effects of the lower dose of chloroquine were more profound. Time-related differences between pretreatments were not observed (P>0.05, all). Conclusion Our study shows for the first time that a single dose of chloroquine (0.3 mg/kg i.v.) could afford significant protection of the injured rat kidney.

Time‐dependent reduction of structural complexity of the buccal epithelial cell nuclei after treatment with silver nanoparticles

Recent studies have suggested that silver nanoparticles (AgNPs) may affect cell DNA structure in in vitro conditions. In this paper, we present the results indicating that AgNPs change nuclear complexity properties in isolated human epithelial buccal cells in a time‐dependent manner. Epithelial buccal cells were plated in special tissue culture chamber / slides and were kept at 37°C in an RPMI 1640 cell culture medium supplemented with L‐glutamine. The cells were treated with colloidal silver nanoparticles suspended in RPMI 1640 medium at the concentration 15 mg L−1. Digital micrographs of the cell nuclei in a sample of 30 cells were created at five different time steps: before the treatment (controls), immediately after the treatment, as well as 15 , 30 and 60 min after the treatment with AgNPs. For each nuclear structure, values of fractal dimension, lacunarity, circularity, as well as parameters of grey level co‐occurrence matrix (GLCM) texture, were determined. The results indicate time‐dependent reduction of structural complexity in the cell nuclei after the contact with AgNPs. These findings further suggest that AgNPs, at concentrations present in todays over‐the‐counter drug products, might have significant effects on the cell genetic material.

Survivin gene promoter -31 G/C polymorphism is associated with Wilms tumor susceptibility in Serbian children.

Survivin, an apoptotic inhibitor, is overexpressed in various types of cancer. Mechanisms of survivin upregulation are still poorly understood, but single nucleotide polymorphisms in the survivin gene promoter have been shown to modulate survivin expression and consequently the risk for some types of cancer. The aim of the present study was to investigate whether survivin promoter −31 G/C and −241 C/T polymorphisms could represent susceptibility factors for Wilms tumor (WT) development in Serbian population. Genotype and allele frequencies for the 2 polymorphisms in survivin promoter have been analyzed by polymerase chain reaction/restriction fragment length polymorphism in 59 WT patients and 82 controls. The frequencies of alleles and genotypes were significantly different between patients and controls for the −31 G/C polymorphism. Individuals with CC and CG genotypes had significantly decreased risk of WT compared with GG individuals (odds ratio 0.26, 95% confidence interval, 0.07-0.96; odds ratio 0.30, 95% confidence interval, 0.15-0.60). There was also a statistically significant difference in genotype frequencies between intermediate and high-risk prognostic groups (P=0.015). The −241 C/T polymorphism did not show association with WT susceptibility. Our findings suggest that the G allele at −31 survivin gene promoter position is associated with a significantly higher cancer risk in Serbian children, with a gene dosage effect.