[Free oxygen radiacals and kidney diseases--part I]. / Kiseonikovi slobodni radikali i oboljenja bubrega--I deo.

ADVERSE EFFECTS OF OXYGEN: Adverse effect of oxygen on anaerobes implies oxidation of the basic cell constituents NAD(P)H, thiols, iron-sulphur proteins, pteridines and others) and inactivation of the essential components of the active site of enzymes. Oxygen can also adversely affect the aerobes, especially if long-term influence is taken into consideration, while exposition to high-pressure oxygen causes considerable damages. Direct influence of oxygen on aerobes due to slow and limited enzyme inactivation (for example glutamate decarboxylase) and small number of affected "targets" is not responsible for total adverse effects of oxygen. Even in 1954 it was supposed that oxygen free radicals are the most responsible for the adverse effects of oxygen. ATMOSPHERIC (TRIPLET) OXYGEN: Electron configuration of triplet oxygen explains its reactivity since it is a biradical. The reactions of oxygen with non-radicals are possible with participation of transition metals (except zinc), while its reactivity is much more expressed in case of reactions with other radical species. ACTIVE OXYGEN: More reactive forms of oxygen, known as singlet oxygen, can be generated by an input of energy to triplet oxygen. Singlet-oxygen is obtained mainly by photoexcitation in the presence of initiators (methylene blue, chlorophyll etc.) and as a product of reactions of ozone with certain biomolecules. REDUCED FORMS OF OXYGEN: If a single electron is added to the triplet oxygen, it must enter one of the antibonding molecular orbitals and produce the superoxide radical--(O2.-). Addition of one more electron produces peroxide ion--O2(2-), which forms hydro peroxide in presence of H+, the most common two-electron reduction product of oxygen in biological systems. The four-reduction product of oxygen in biological systems is water. SUPEROXIDE RADICAL: The in vivo production of superoxide radical is possible in many different ways mentioned in this paper. This radical species is unstable in water solutions because of dismutation reaction leading to non-enzymic generation of hydroperoxide. The most reactive radical species--hydroxyl radical is produced from hydro peroxide by Fenton or Haber-Weiss reactions in the presence of catalytic transition metals (iron or copper). HYDROXYL RADICAL: Hydroxyl radicals are the most reactive radical species. The way of their generation has been shown in detail in this paper with special emphasis given to Fenton and Haber-Weiss reactions, that is, transition metals (iron and copper) as catalizators for these reactions. The reactivity of hydroxyl radical can be recognized by monitoring the second-order rate constants for reactions of the hydroxyl radical with some organic compounds in aqueous solution presented in this paper. Although the number of compounds that can be affected and damaged by hydroxyl radicals is great, until now, attention has been paid mostly to investigation of attacks of these radical species on lipids, proteins and DNA. LIPID PEROXIDATION: Radicals react with lipids and cause oxidative destruction of unsaturated, that is, polyunsaturated fatty acids, known as lipid peroxidation. Both lipids in biological systems and lipids as food constituents are submitted to this process. Lipid peroxidation is a chain reaction and its mechanism has been shown in detail in this paper. Lipid peroxidation in cells leads to direct damage of cell membranes with indirect damages of other cell constituents, caused by reactivity of secondary products of this reaction, aldehydes. This complex reaction is responsible for damages of many tissues and progress of some diseases (atherosclerosis). OXIDATIVE STRESS: Protection of an organism from oxygen free radicals implies activity of enzymatic (catalase, SOD, glutathione peroxidase, glutathione reductase etc.) and nonenzymatic (vitamin E. vitamin C. glutathione, uric acid etc.) systems of protection. Disturbance of the balance between production of oxygen free radicals (or some other radical species) and activity of antioxidative system of protection causes the so called oxidative stress. An organism can tolerate a mild oxidative stress but a higher disturbance between the production of free radicals and the activity of the antioxidative protection results in lipid protein and DNA as well as numerous diseases.

[Anti-U1RNP antibodies and lupus nephritis]. / Anti-U1RNP antitela i lupusni nefritis.

INTRODUCTION: Systemic Lupus Erythematosus is characterized by production of numerous autoantibodies as an abnormal immune response. The most important antibodies are those aimed at constitutive elements of cell nucleus. METHODS: After antigen typing of antinuclear antibodies in 30 patients with Systemic Lupus Erythematosus we analyzed the correlation between anti-Sm antibodies and anti-U1RNP antibodies and the degree of disease activity, such as correlation of these two antibodies with some clinical manifestations of this disease. This study included patients who fulfilled all revised American Rheumatism Association criteria to diagnose systemic lupus. To determine the degree of disease activity we used Systemic Lupus Erythematosus Disease Activity Index after Bombardier. To detect antinuclear antibodies technique of indirect immunofluorescence and ELISA procedure for antigen typing of these antibodies were used. RESULTS: We registered antinuclear antibodies (ANA) in 100% of our patients, with domination of homogenous pattern of immunofluorescence (70%). Speakled pattern was registered in 16.66% and margin type in 6.66%. Using ELISA procedure of antigen typing of ANA we registered anti-U1RNP antibodies in 26.7% patients, while anti-Sm antibodies were registered in 20%. CONCLUSION: Anti-U1RNP antibodies finding is associated with mild forms of disease and rare appearance of lupus nephritis, while anti-Sm antibodies finding is characteristic for very active forms of disease and often lupus nephritis.

[Systemic necrotizing vasculitis: case report]. / Sistemski nekrotizirajuci vaskulitis: prikaz slucaja.

Systemic vasculitis presents a group of clinically pathologic syndromes with acute inflammatory process in its basis which commonly occurs on small blood vessels destroying their walls with fibrinoid necrosis. It often occurs on several organs and systems depending on the form, size and number of the diseased blood vessels. This paper is a case report on a female patient suffering from a serious systemic necrotizing vasculitis with clinically demonstrated ulceronecrotizing skin changes and purpura together with appearance of coronary ischemia; rhythmic disorders of heart rate and gastrointestinal bleeding and cardiac arrest in one moment. It contains a description of the course of the disease and a good result after application of immunosuppressive therapy with high doses of corticosteroids, cyclosporin A and plasmaphereses.

[Results of a multi-year study of persons with transplanted kidneys]. / Rezultati visegodisnjeg ispitivanja osoba s transplantisanim bubregom.

The authors review their results of five year follow up of renal transplantation. They summarised the results of treatment with three immunosuppressive regimens. There is an analysis of rejection episodes, recurrent glomerulonephritis, infections, surgical complications, a median graft as well as patient survival and other patterns of complications of renal transplantation.

[Urinary infections in patients with transplanted kidneys]. / Urinarne infekcije kod bolesnika s transplantisanim bubregom.

The aim of this study was to evaluate urinary infection frequency in kidney transplanted patients. Infection frequency was assessed in 116 patients (81 males and 35 females; mean age 36.2 years) after renal transplantation. During four year follow-up 41% patients suffered one or more episodes of infection. Bacterial infection caused by Escherichia coli were most frequent. The control group consisted of healthy medical staff and the investigations showed significantly over frequency of infection.

[Clinical and morphologic features in patients with acute nephritis syndrome]. / Klinicke i morfoloske odlike bolesnika s akutnim nefritisnim sindromom.

Acute glomerulonephritis is a distinct clinical entity, more frequently found in younger age. We report 69 patients with AcGN (25 female and 44 male) mean age 26 years (range 15-58). The disease is clinically characterized with hypertension (57%), edema (59%) and oliguria (35%). Urine analysis showed microhaematuria/proteinuria (36%) and micro/macrohaematuria alone in 89%, while azothaemia was observed in 16% pts, and decreased serum complement levels in one third of patients, more often decrease of C3 (33%) than C4 (15%). Initial infection of the upper respiratory tract was seen in 65%, pneumonia in 8%. In 25% of pts. there were no data of previous infection. Cultures of pharyngeal smear revealed. Streptococcus only in 2 pts. Elevated AST titer was found in 32% pts. Eleven kidney biopsies were made, and histological examination showed 2 normal findings, 6 mesangioproliferative GH, 2 endocapillary GN and 1 membranoproliferative GN. Follow ups have showed urinary abnormalities in 25% of pts., without developing renal failure.

[Methylprednisolone pulse therapy in the early phases of lupus nephritis]. / Dejstvo pulsne terapije metilprednozolonom kod ranih faza lupusnog nefritisa.

Renal involvement i.e. lupus nephritis (LN) in systemic lupus erythematosus (SLE) mainly determines course and outcome of the disease. Recognition of early manifestations of LN makes adequate therapy possible, with very good therapeutic results. We report 7 patients from a group of 150 SLE patients under our permanent control, 4 female and 3 male, mean age 21 years. All of them had signs of LN: proteinuria 7/7 haematuria 4/7 without azotaemia. Renal biopsy was performed in 6 pts, and histological finding was: class II 1 pt, class IV 3 pts and class V in 2 pts. In 4 pts tubulointerstitial changes were noted, while all showed immunofluorescent deposits of immunoglobulins and complement. Methylprednisolone "pulse" therapy (1000 mg, i.v., 3 days) followed by tapering of the steroid dose was given. Reduction of proteinuria and disappearance of haematuria were observed in all patients. During follow up, kidney function remained normal.