Seroprevalence, Direct Detection and Risk Factors for Toxoplasma gondii Infection in Pigs in Serbia, and Influence of Biosecurity Measures

Consumption of Toxoplasma gondii contaminated pork is a major risk factor for human infection. We thus conducted a cross-sectional survey on the seroprevalence of T. gondii infection in a representative sample of slaughter pigs from throughout Serbia and examined the influence of farm biosecurity-related risk factors on infection. In addition, direct detection of the parasite (by mouse bioassay) or its DNA was performed in the hearts of a subset of seropositive sows. The overall seroprevalence in the sample of 825 pigs as determined by the modified agglutination test (MAT) was 16.5%. Older age and inadequate rodent control were independent infection risk factors for pigs. In a subset of 581 pigs with complete biosecurity-related data, in addition to older age, smallholders’ finishing type farms (as opposed to farrow-to-finish), multispecies farming, and origin from Western and Central and South-Eastern Serbia (vs. the Northern region), all increased the risk of infection, while the absence of disinfection boot-dips in front of each barn and Belgrade district origin (vs. the Northern region) were associated with a 62% and 75% lower risk of infection, respectively. Evidence of viable parasites was obtained in 13 (41.9%) of the 31 bioassayed sow hearts, of which by isolation of brain cysts in seven, by detection of T. gondii DNA in an additional four, and by serology in another two. Recovery of brain cysts mostly (5/7) from sows with a MAT titre of ≥1:100 indicates the risk for consumers. These results highlight the public health risk from pork consumption and point to mandatory use of professional rodent control services, abstaining from multispecies farming, keeping disinfection boot-dips clean and freshly refilled, as well as strict implementation of zoo-hygienic measures on smallholders’ farms as specific farm biosecurity measures needed for its reduction.

Quantities, environmental footprints and beliefs associated with household food waste in Bosnia and Herzegovina

The objectives of this research were to identify the quantities and global warming, acidification and eutrophication potentials associated with household food waste in Bosnia and Herzegovina. In parallel, this study investigated perceptions related to food waste and using the quality function deployment for environment model, correlated reasons for discarding food waste and beliefs associated with food waste. Based on this study, it is estimated that around 2.8 kg of food waste is disposed of by the average household every week. Global warming, acidification and eutrophication potentials associated with household food waste are, on average, 3.49 kg CO₂e/week, 2.42 g SO₂e/week and 8.70 g PO₄e/week, respectively. Also, Bosnian households discard over 80 different pieces of food packaging waste weekly, where plastic packaging is the most dominant packing type. The highest ranked reason for discarding food is linked to plate leftovers. In general, Bosnian citizens feel guilty when they waste food.

Effect of Adequacy of Dialysis and Nutrition on Morbidity and Working Rehabilitation of Patients Treated by Maintenance Hemodialysis

Numerous studies have demonstrated a correlation between adequacy of hemodialysis (HD) and patient mortality. In this study we evaluated the effect of adequacy of dialysis and nutrition on morbidity and working rehabilitation. Single center experience carried out in 1998 in an outpatient university-affiliated dialysis facility was presented. A total of 181 patients, on HD over 3 months, was included in the study; mean age 54.5 years, mean duration of HD 5.4 years. Thirthy-two patients were hospitalized in 1998. Patients with an eKt/V < 0.8 had significantly more frequent and extended hospitalizations than patients with eKt/V > 1.2. In the regression model eKt/V had a significant effect on hospital days. Serum albumin, as an index of nutrition, was also found to significantly influence hospitalizations. Patients with a BMI < 20.0 kg/m2 were found to have significantly more frequent hospitalizations, more hospital days/patient, and hospital days/hospitalized patient/year than those with a BMI > 25.0 kg/m2. BMI < 20.0 kg/m2 was associated with a significantly lower dialysis adequacy (eKt/V and URR) and more severe anemia. However, regression model failed to confirm a statistically significant association of BMI with hospital days. The best working rehabilitation (stage 1), according to the EDTA criteria, was obtained in patients with significantly (p<0.05) higher eKt/V, URR, albumin, nPNA, and body fat than in patients at stage 6 (not able to work, and not able to take care of themselves).

This study has established that dialysis adequacy and nutrition have an effect on morbidity (estimated through hospitalizations) and patient rehabilitation. (Int J Artif Organs 2000; 23: 83–9)

Prevention of Nosocomial Transmission of Hepatitis C Infection in a Hemodialysis Unit. A Prospective Study

Hepatitis C virus (HCV) infection in hemodialysis patients can be transmitted by transfusions and nosocomially. A high prevalence of HCV infection, over 50%, was demonstrated in our hemodialysis (HD) unit. In order to prevent the nosocomial spread of HCV infection in the HD unit a prospective study was begun separating anti-HCV positive patients from the negative ones. A total of 170 patients (83 anti-HCV positive) started this study in September 1994 and were followed for 4 years. A separate room and dedicated equipment were assigned to anti-HCV positive and anti-HCV negative patients. Of those 170 patients there were 15 hepatitis B virus (HBV) positive patients, 5 of whom were anti-HCV positive, who were treated in a separate room on dialysis equipment for anti-HCV positive or negative patients. Application of general precautions, as recommended by the Center for Disease Control and Prevention (CDC), was reinforced. During the first 12 weeks after implementing the precautions seven more anti-HCV positive patients were detected, and by December 1995 another two HCV infected patients were found. The follow-up included all changes in HD population treated until the end of 1998. The incidence of seroconversion to HCV was 12.9% in 1995, 7.1% in 1996, 5.0% in 1997, and 6.6% in 1998. The higher incidence of seroconversion in September to November 1994 was probably due to the nosocomial infection being in the incubation period at the time of isolation.

This prospective study in a large HD unit with a high prevalence of HCV infection demonstrates a relatively successful prevention of HCV spread. Procedure-related transmission of HCV in hemodialysis could be prevented by rigorous application of universal precautions as recommended by the CDC. As a second line of prevention, in highly burdened dialysis centers, segregation of HCV positive patients can help control nosocomial transmission.

Aroma formation by immobilized yeast cells in fermentation processes

Immobilized cell technology has shown a significant promotional effect on the fermentation of alcoholic beverages such as beer, wine and cider. However, genetic, morphological and physiological alterations occurring in immobilized yeast cells impact on aroma formation during fermentation processes. The focus of this review is exploitation of existing knowledge on the biochemistry and the biological role of flavour production in yeast for the biotechnological production of aroma compounds of industrial importance, by means of immobilized yeast. Various types of carrier materials and immobilization methods proposed for application in beer, wine, fruit wine, cider and mead production are presented. Engineering aspects with special emphasis on immobilized cell bioreactor design, operation and scale-up potential are also discussed. Ultimately, examples of products with improved quality properties within the alcoholic beverages are addressed, together with identification and description of the future perspectives and scope for cell immobilization in fermentation processes.

Late-appearing pseudocentric fission event during chronic myeloid leukemia progression

Pseudocentric fission is a rare event consisting of the splitting of one functional centromere into two new products, of which only one can give rise to a functionally competent kinetochore. We report here a pseudocentric fission event within the D5Z2 alphoid subset disrupting the centromeric region of chromosome 5 in a case of chronic myeloid leukemia (CML) after treatment with imatinib and interferon. The breakage generated unequal partitioning of alpha-satellite sequences between the two fission products. One product was inserted within the long arm of chromosome 12 at band 14.3, becoming the only functional centromere of chromosome der(5). The other fission product was rearranged to form a sandwich-like dicentric--but functionally monocentric--chromosome der(6), made up of material from chromosomes 5, 12, and 6. The intercentric distance on der(6) was shown to be largely >20 Mb. To our knowledge, this is the first pseudocentric fission event described in CML. Moreover, our results confirm the susceptibility to breakage of the centromeric region of chromosome 5.

[Aberrations of chromosome 8 in myelodysplastic syndromes: clinical and biological significance]

INTRODUCTION

Rearrangements of any single chromosome in human karyotype have been reported in patients with pMDS.

OBJECTIVE

To examine the role of aberrations of chromosome 8 in pathogenesis, clinical presentation and progression of myelodysplastic syndromes.

METHOD

Cytogenetic analysis of bone marrow cells was carried out by direct method and by means of 24- and/or 48-hour unstimulated cell culture. Chromosomes were obtained by modified method of HG-bands.

RESULTS

On presentation, 109 out of 271 successfully karyo-typed patients (40,2%) had abnormal karyotypes. Among them, 22 patients (10.9%) had aberrations of chromosome 8. Ten patients had trisomy 8 as "simple" aberration whilst additional three cases had trisomy 8 included in "complex" karyo-types (> or =3 chromosomes). Cases with constitutional trisomy 8 mosaicism (CT8M) were excluded using the chromosome analyses of PHA-stimulated blood cultures. On the contrary, monosomy (seven patients) or deletion of chromosome 8 (two patients) were exclusively found in "complex" karyo-types. During prolonged cytogenetic follow-up, trisomy 8 was not recorded in evolving karyotypes. In contrast, trisomy 8 disappeared in two cases during subsequent cytogenetic studies, i.e. 23 and 72 months from diagnosis, accompanied in one patient with complete hematological remission. No difference regarding age, sex, cytopenia, blood and marrow blast count or response to treatment was found between patients with trisomy 8 as the sole aberration compared to those with normal cytogenetics. Median survival of patients with trisomy 8 as the sole aberration was 27 months, as compared to 32 months in patients with normal cytogenetics (p = 0.468), whilst median survival of patients with aberrations of chromosome 8 included in "complex" karyotypes was only 4 months.

CONCLUSION

Aberrations of chromosome 8 are common in patients with pMDS. The presence of a clone with trisomy 8 is not always the sign of disease progression or poor prognosis in MDS patients, in contrast to clones with aberrations of chromosome 8 manifesting the loss of genetic material.

Spontaneous remission in adults with primary myelodysplastic syndromes: incidence and characteristics of patients

Reports on spontaneous remissions in patients with primary myelodysplastic syndromes (MDS) occasionally appear in the literature. We report five adult patients with spontaneous remission of MDS, achieved without cytotoxic or any other treatment. These five patients represent 1.6% of 307 MDS patients, diagnosed in our Institute since 1987. According to FAB criteria, three patients had RA, and one patient had RARS and RAEB, each. All patients were women, median age of 63 yr (range 32-68 yr). Patients were without significant complaints and peripheral cytopenia was mild. Bone marrow dyshematopoiesis was also mild, mostly affecting erythroid and megakaryocytic series. At diagnosis, three patients had cytogenetic abnormalities [+8,+12; +15 and del(16)(q22)]. Median time to complete hematological and cytogenetical remission was 51 mo, while median duration of spontaneous remission was 45 mo (range 44-60 mo). As for the follow-up, none of the patients relapsed. In conclusion, although spontaneous remissions (i.e., "regression") of MDS are uncommon, better understanding of their basis may lead to crucial advances in the study of leukemogenesis.

Ionization energies of LinX (n = 2, 3; X = Cl, Br, I) molecules

Molecules of Li(n)X (n = 2, 3; X = Cl, Br, I) were examined with a magnetic sector mass spectrometer by surface ionization using a triple rhenium filament impregnated with fullerene (C60). The ionization energies obtained for Li(2)Cl, Li(2)Br and Li(2)I molecules are 3.8 +/- 0.1, 3.9 +/- 0.1 and 4.0 +/- 0.1 eV, respectively. The first ionization energy of Li(2)Cl is documented, while there are no literature data for the ionization energies of Li(2)Br and Li(2)I. The molecules of Li(3)Cl, Li(3)Br and Li(3)I were detected experimentally for the first time with ionization energies of 4.0 +/- 0.1, 4.1 +/- 0.1 and 4.1 +/- 0.1 eV, respectively. The ionization energies of Li(n)X (n = 2, 3; X = Cl, Br, I) are in correlation with the theoretical prediction of their hyperlithiated configurations.

[Radical surgery of the malignant laryngeal tumors]

Modern therapeutical protocols for treatment of T3 and T4 malignomas of the larynx are not adjusted, because there are attempts to treat these diseases with non-operative methods (such as chemo- and radiotherapy) in order to preserve the organ. The aim of the study was to establish today's results of the surgical treatement of patients with T3 and T4 laryngeal malignoma. We studied the group of patients with laryngeal carcinoma, who had undergone total laryngectomy, during the period of eight years (1990-1997). The patients' data was submitted from medical documentation, it was filled in specially designed questionnaries and was statistically reviewed. During this eight-year-period, 1054 total laryngectomies were done. The five-years survival rate, established in the group of patients who had undergone total laryngectomiy is 308/794 (39%). In the patient group where total laryngectomy was salvage surgery after radiotherapy, the five-years survival rate is 47/172 (27%). In the patient group where total laryngectomy was salvage surgery after conservative or reconstructive surgery, the five-years survival rate is 28/84 (33%). Despite diagnostical and therapeutical achievements, prognosis for T3 and T4 malygnoma of the larynx was not significantly approved in the last few decades.

[Results of hemilaryngectomy in primary surgical treatment of laryngeal carcinoma]

Hemilaryngectomy is the resection of a true anatomic half of the larynx with preservation of the cricoid cartilage. We present a retrospective study of 438 patients with glottic carcinoma, treated with hemilaryngectomy, at the Institute of Otorhinolaryngology and Maxillofacial Surgery, Clinical Center of Serbia between 1988 and 1997. The patients with positive margins (19.4% of all) were postoperatively irradiated. Local recurrences of carcinoma were found in 17.3% of subjects, and regional recurrences in 16.4% of subjects. Those patients were treated with total laryngectomy or radical neck dissection, and with radiotherapy. 5-years survival rate in our patients was 79%. Hemilaryngectomy provided acceptable percent of local and regional recurrences, and good functional results: respiration, swallowing and voice quality. Therefore it could be the first choice surgery technique in treatment of T2 laryngeal carcinoma.

[Chromosome 17 abnormalities in patients with primary myelodysplastic syndrome: incidence and biologic significance]

Cytogenetic analysis has proven to be a mandatory part of the diagnosis of myelodysplastic syndromes (MDS) as well as a major indicator for predicting clinical course and outcome. Aside from the 5q-syndrome, no specific clinico-cytogenetic entity has been reported. To determine the incidence and clinical significance of acquired abnormalities of chromosome 17 in adult primary MDS, we reviewed the cytogenetic features of 271 patients detected at our institution during a 10-year period. Clonal cytogenetic abnormalities were identified in 109 cases. Among them, abnormalities of chromosome 17 were identified in 13 patients (11.9%). Five patients had "single" defects, while in eight patients abnormalities of chromosome 17 were associated with other chromosomal rearrangements ("complex" defects). After chromosomes 5, 7, 8 and 1, abnormalities of chromosome 17 were the most frequent chromosomal rearrangements in our patients with MDS. Following "single" defects of chromosome 17 were identified: del(17)(p12) in two cases, and i(17)(q10), del(17)(q21;q23) and del(17)(q12;q22) in one case each. Two patients with del(17p), one with RAEB-t and the other one with CMML, had an aggressive course of the disease with accelerated leukemic transformation and short survival. Patient with i(17q) had RARS subtype and died soon after diagnosis, while other two cases with interstitial deletions of the long arm of chromosome 17 had RAEB subtype and stable, no progressive course of the disease. Among "complex" karyotypes with abnormalities of chromosome 17 we identified der(17) in four, monosomy 17 in two, and del(17p) and l(17q) in one case each. Most of these patients transformed to acute leukemia and had very short survival. The results of this study suggest that abnormalities of chromosome 17 are frequent finding in MDS. Loss of genetic material in 17p, both in "single" and "complex" defects, seems to be closely related to poor prognosis of MDS patients.

Influence of the incubation atmosphere on the production of biofilm by staphylococci

Biofilm formation by Staphylococcus epidermidis, Staphylococcus hemolyticus, Staphylococcus sciuri and Staphylococcus aureus in aerobic, anaerobic and CO2 incubation atmospheres was quantified by the modified microtiter plate test. The S. epidermidis and S. aureus strains showed significantly lower biofilm production when grown in a CO2-rich environment compared to that exhibited in aerobic incubation. The amount of biofilm produced by these strains under anaerobic conditions did not differ significantly from the biofilm formation detected in the aerobic incubation. The incubation atmosphere did not affect S. sciuri biofilm formation. Biofilm production by S. hemolyticus isolates was very low regardless of the experimental conditions used.

[Use of fibrin glue in the prevention of leakage in pancreatico-jejunal anastomoses]

The aim of this study was to test the protective effects of fibrin sealing on the pancreatico-jejunostomy (PJA), the high-risk anastomosis following pancreas head resection. Experimental study was performed on the mongrel dogs, divided in two groups (20 animals each): Experimental group-with end to end "dunking" PJA, protected by temporary occlusion of the pancreatic duct with fibrin sealant/Tissucol/Immuno Ag/, while control group was without any protective procedure. The animals were followed 5 months in order to study: protective effects of such procedure on the PJA quantified with the percent of anastomotic leakage, effects of the exocrine secretion and effects the endocrine function Results: PJA leakage occurred in 13.33% in control group. No leakage was registered in experimental group. Biochemical, histological and electron microscopic study showed slight transitory elevation of amylase levels. Fibrin glue plug was dissolved and pancreatic juice output was reestablished 12th days postoperatively. Long term follow-up showed no damages of the endocrine and exocrine pancreas. Pancreatic duct occlusion with fibrin glue appeared to be an useful method in the prevention of pancreatico-jejunostomy leakage, without negative effects on the exocrine and endocrine pancreas.

Epidemiology of end-stage renal disease and current status of hemodialysis in Yugoslavia

Maintenance hemodialysis (HD) in Yugoslavia started in the sixties and followed the dialysis trends in the Western Europe. However, in the last decade the development of renal replacement therapy (RRT) slowed down. In this report the epidemiology of ESRD from 1997-1999 and the survey of the status of HD treatment in Yugoslavia in 1999 are presented. Epidemiological data are obtained by the annual center questionnaires (response rate: 92.6 -94.2%). The survey of HD status is based on a specific questionnaire and covered 2108 patients (65%). At the end of 1999 there were 56 RRT centers in Yugoslavia treating 3939 patients: 3232 (82%) patients by HD, 248 (6.3%) by peritoneal dialysis, and 459 (11.7%) living with transplanted kidney. In a three year period, incidence of ESRD ranged from 108-128 pmp, point prevalence from 435-463 pmp and mortality rate from 20.7-17.9. Numerous refugee patients were treated over the last 10 years. Main causes of ESRD were glomerulonephritis (30%); Balkan nephropathy represented 11% and diabetic nephropathy 7% of all primary renal diseases. Cardiovascular and cerebrovascular diseases were the most common causes of death of RRT patients. Most centers are overcrowded and HD machines are worn out. Mean Kt/V was 1.19+/-0.08, mean URR% 58.8+/-7.4. The shortage of drugs prevented adequate management: 83% of HD patients had hemoglobin level less than 100 g/L but only 10.3 -17.8% were treated with rHuEpo; 64.5% of patients had phosphate levels higher than 1.7 mmol/L but only 33.5% used phosphate binders; 47% of patients had hypertension despite the antihypertensive therapy. The prevalence of hepatitis B remained unchanged (about 14%) in HD population during the last three years, but the prevalence of anti-HCV positive patients decreased (31-23%). In conclusion, there is a well developed dialysis service in Yugoslavia but insufficient conditions for adequate treatment.

Refractory anemia with ring sideroblasts associated with i(17q) and mutation of the TP53 gene

A patient with a myelodysplastic syndrome ([MDS], i.e., refractory anemia with ring sideroblasts [RARS]) and a rapidly fatal clinical course is presented. A cytogenetic analysis showed an isochromosome 17q as a sole abnormality in all metaphases. An association between RARS and i(17q) has not been reported. Furthermore, a mutation of the remaining TP53 gene in exon 6 was evidenced by a single strand conformation polymorphism technique. This unique case illustrates heterogeneity of phenotypic expression of a stem cell disorder in MDS and indicates precaution in classifying hematologic syndromes especially when morphology is correlated with specific cytogenetic changes.

Prevention of nosocomial transmission of hepatitis C infection in a hemodialysis unit. A prospective study

Hepatitis C virus (HCV) infection in hemodialysis patients can be transmitted by transfusions and nosocomially. A high prevalence of HCV infection, over 50%, was demonstrated in our hemodialysis (HD) unit. In order to prevent the nosocomial spread of HCV infection in the HD unit a prospective study was begun separating anti-HCV positive patients from the negative ones. A total of 170 patients (83 anti-HCV positive) started this study in September 1994 and were followed for 4 years. A separate room and dedicated equipment were assigned to anti-HCV positive and anti-HCV negative patients. Of those 170 patients there were 15 hepatitis B virus (HBV) positive patients, 5 of whom were anti-HCV positive, who were treated in a separate room on dialysis equipment for anti-HCV positive or negative patients. Application of general precautions, as recommended by the Center for Disease Control and Prevention (CDC), was reinforced. During the first 12 weeks after implementing the precautions seven more anti-HCV positive patients were detected, and by December 1995 another two HCV infected patients were found. The follow-up included all changes in HD population treated until the end of 1998. The incidence of seroconversion to HCV was 12.9% in 1995, 7.1% in 1996, 5.0% in 1997, and 6.6% in 1998. The higher incidence of seroconversion in September to November 1994 was probably due to the nosocomial infection being in the incubation period at the time of isolation. This prospective study in a large HD unit with a high prevalence of HCV infection demonstrates a relatively successful prevention of HCV spread. Procedure-related transmission of HCV in hemodialysis could be prevented by rigorous application of universal precautions as recommended by the CDC. As a second line of prevention, in highly burdened dialysis centers, segregation of HCV positive patients can help control nosocomial transmission.

Effect of adequacy of dialysis and nutrition on morbidity and working rehabilitation of patients treated by maintenance hemodialysis

Numerous studies have demonstrated a correlation between adequacy of hemodialysis (HD) and patient mortality. In this study we evaluated the effect of adequacy of dialysis and nutrition on morbidity and working rehabilitation. Single center experience carried out in 1998 in an outpatient university-affiliated dialysis facility was presented. A total of 181 patients, on HD over 3 months, was included in the study; mean age 54.5 years, mean duration of HD 5.4 years. Thirty-two patients were hospitalized in 1998. Patients with an eKt/V < 0.8 had significantly more frequent and extended hospitalizations than patients with eKt/V > 1.2. In the regression model eKt/V had a significant effect on hospital days. Serum albumin, as an index of nutrition, was also found to significantly influence hospitalizations. Patients with a BMI < 20.0 kg/m2 were found to have significantly more frequent hospitalizations, more hospital days/patient, and hospital days/hospitalized patient/year than those with a BMI > 25.0 kg/m2. BMI < 20.0 kg/m2 was associated with a significantly lower dialysis adequacy (eKt/V and URR) and more severe anemia. However, regression model failed to confirm a statistically significant association of BMI with hospital days. The best working rehabilitation (stage 1), according to the EDTA criteria, was obtained in patients with significantly (p<0.05) higher eKt/V, URR, albumin, nPNA, and body fat than in patients at stage 6 (not able to work, and not able to take care of themselves). This study has established that dialysis adequacy and nutrition have an effect on morbidity (estimated through hospitalizations) and patient rehabilitation.

Selenium-dependent and selenium-non-dependent glutathione peroxidase in patients with Balkan endemic nephropathy

We studied the activity of erythrocyte selenium (Se)-dependent, Se-non-dependent glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) in uremic patients (UP) in clinically healthy members from families affected with Balkan nephropathy (HMF/BEN) and in healthy volunteers from endemic settlements (control group). The SOD activity was not significantly different in the groups studied and the Se-non-dependent GSH-Px activity in HMF/BEN and UP was not different from the control group. However, the activity of Se-dependent GSH-Px in UP was lower compared with the control group, whereas the mean value of the Se-dependent GSH-Px activity in HMF/BEN was not significantly different when compared with the other two investigated groups.

Inversion of chromosome 16 in accelerated phase of chronic myeloid leukaemia: report of a case and review of the literature

A patient with a Philadelphia chromosome-positive (Ph+) chronic myeloid leukemia (CML) developed a blast crisis (FAB subtype AML-M2) without a monocytic involvement. Karyotype showed the presence of inv(16)(p13;q22) in addition to Ph, in 16/20 marrow metaphases.

[The effect of alphacalcidol on calcium and phosphate metabolism in patients treated with hemodialysis]

The purpose of these studies was to assess the effect of 6 month calcidol treatment on Ca and PO4 metabolism in haemodialyzed patients. During 3 and 6 month on alpha calcidol therapy, there was significant increase of total and ionized Ca (p < 0.05; p < 0.01 respectively). After 6 months on alpha calcidol therapy there was significant decrease of alkaline phosphatase level (p < 0.05) and increase in bone density (up to 82%, p < 0.05). The study has shown that appropriate use of alpha calcidol could be effective in treatment of Ca and PO4 disbalance in haemodialyzed patients.

[The effect of frequent peritonitis on parameters of efficacy of peritoneal dialysis]

The estimation of CAPD efficacy presents a complex problem in the patients treated by this method. The most important parameters are: clinical indications, biochemical parameters, Kt/v, PCT, PET indexes, and others. Numerous factors may influence CAPD efficacy. Peritonitis, particularly the frequent episodes, significantly affects permeability and ultrafiltration capacity of the peritoneal membrane. The aim of this paper is to investigate the peritonitis incidence and its influence on some parameters of CAPD efficacy. Forty-four CAPD patients of both sexes, aged 55.7 +/- 13.5 yrs, dialysis duration 19.6 +/- 15 months, were studied. The influence of peritonitis incidence was studied using urea, creatinine, hemoglobin, hematocrit parameters and K t/v, PET indexes. Statistically significant low K t/v values were found in the patients who had four or more peritonitis episodes. Our results, as well as those in the literature, indicate that frequent peritonitis episodes significantly decrease the peritoneal membrane permeability.

[Our protocol in the treatment of peritonitis in patients on continuous ambulatory peritoneal dialysis]

Peritonitis is a very serious complication in patients treated by CAPD. The frequent and grave episodes are the main cause for CAPD withdrawal. The effective prevention and adequate therapy of peritonitis are very important for a successful CAPD treatment. The aim of this study was to present our results of peritonitis therapy in CAPD patients using the following protocol: Vancomycin 1.0 g.i.p. immediately after the admission to the unit, 250 mg Ceftriaxon (Longaceph) after a bag exchange for seven days, and the 1.0 g Vancomycin. Using this protocol we treated 97 peritonitis episodes; 74 of them (80%) were treated successfully by this antibiotics combination. The clearness of peritoneal fluid was attained 1-3 days within 56.7% of cases, and 4-6 days within the 29.7% peritonitis episodes (86.4%). A common cause of peritonitis was Staphylococcus epidermidis episodes (28.4%), Staphylococcus aureus (13.5%), and in 39.1% episodes the cultures were sterile. Uneffective antibiotic application according to this protocol was found in cases of pseudomonas and fungal peritonitis. The mentioned antibiotic therapy had no effect in a small number of peritonitides provoked by S. epidermidis (8.7%) and S. aureus (13.0%) This required the application of a third antibiotic. It could be concluded that this antibiotic combination in treatment of peritonitis in patients on CAPD was very effective.

[Lupus glomerulonephritis--clinico-morphologic correlation]

In a period of 10 years we performed renal biopsies in 13 patients with systemic lupus erythematosis, the results showed mild changes and focal glomerulonephritis in 30%, diffuse glomerulonephritis in 23% and membranous nephropathy and sclerotic glomerulonephritis in 15% of patients. In the follow-up period three patients died. Prognosis of severe lupus nephritis is better nowadays because of improved therapy. Adverse effects of the applied therapy should not be overlooked while arterial hypertension should be suppressed.

Receptor-mediated induction of human glomerular epithelial cell alkaline phosphodiesterase I by glucocorticoids

Alkaline phosphodiesterase I was demonstrated in human glomerular mesangial cells (HGEC) as an ectoenzyme. Treatment of HGEC by dexamethasone increased surface phosphodiesterase I activity in a dose- and time-dependent manner. Maximal increase of phosphodiesterase I activity, about twice, occurred after treatment with 5 microM dexamethasone for 6 days. Cycloheximide prevented and RU 38486, a glucocorticoid receptor antagonist, suppressed the dexamethasone induced increase in phosphodiesterase I activity. This study shows that HGEC have a surface phosphodiesterase I controlled by glucocorticoids through a receptor-mediated mechanism.

Blood coagulation factors changes during liver regeneration in rats

Effects of partial hepatectomy on blood coagulation factors were investigated in rats. Analysis were performed 24, 48 and 72 hours after surgery. Howell's time was significantly higher after 24 and 48 h compared to the control value. Prothrombin time was significantly prolonged after 24 h. Partial thromboplastin time did not differ significantly in any time. FII values were significantly reduced after 24 and 48 h, but FV values only after 24 h. FVII showed significant decrease after 24 h, but significant increase at 48 h. FVIII and ATIII average values were significantly lower after 24, 48 and 72 h. Plasma fibrinogen increased. Significant differences were observed 48 and 72 h after surgery. Differences in normalization time of these coagulation factors are most probably the consequence of their synthesis in various cell types, regenerated at different periods after partial hepatectomy.

Chronic biofiltration therapy

Long-term follow-up evaluation of biofiltration treatment in 7 patients is presented. These patients experienced frequent episodes of hypotension during acetate hemodialysis. A 3-year biofiltration treatment reduced by 43% episodes of symptomatic hypotension and produced a significant increase in the pretreatment pH and plasma bicarbonate levels. The beta 2-microglobulin level was significantly reduced during biofiltration therapy. The mean systolic and diastolic blood pressures slightly increased during biofiltration. Uremic polyneuropathy, as demonstrated by an increase in motor nerve conduction velocity, slightly improved. The patients reported increased comfort during biofiltration therapy.

Thyroid hormone profiles in experimental acute renal failure

Thyroid hormone profiles were determined in two groups of dogs made uremic, either by i.v. uranyl nitrate 10 mg/kg BW injection or by bilateral ureteral ligation, and in one group of sham-operated animals. Each group consisted of 6 dogs and served as its own control. From blood samples taken in 12-h intervals up to 144 h for uranyl nitrate-injected dogs and 96 h for operated dogs, serum levels of T4, T3, fT4, fT3, rT3, and cortisol were measured by radioimmunoassays. The results obtained in both groups of uremic dogs showed an initial sharp fall of T4, T3, fT4, and fT3 followed by a plateau or retarded decrease. In sham-operated dogs the fall of these hormones was slight and of short duration. Reverse T3 had a tendency to increase in all groups examined, but a significant elevation was recorded only after bilateral ureteral ligation. In this group cortisol serum levels were found the highest, being also significantly increased in the other two groups. The temporal coincidence of the most marked alterations in T3, rT3, and cortisol serum concentrations indicates a significant role of stress in thyroid dysfunction. Although serum creatinine rise and weight loss were not parallel with thyroid hormone alterations, the involvement of uremic compounds and malnutrition in this process is also quite clear. Thus, the data presented suggest simultaneous influences of uremic toxins, stress, and malnutrition on the induction of thyroid dysfunction in dogs made uremic by uranyl nitrate injection or bilateral ureteral ligation.(ABSTRACT TRUNCATED AT 250 WORDS)

[Diurnal changes in the levels of immunoreactive parathyroid hormone and calcitonin in patients with chronic renal insufficiency]

The circadian rhythms of the serum immunoreactive parathyroid hormone (iPTH) and calcitonin concentration were examined in 6 patients with chronic renal failure (CRF) not treated by haemodialysis. In 3 patients on haemodialysis the influence of haemodialysis with cuprophan and polyacrylonitrile membranes (in a.m. and p.m. periods of day) on serum concentration of these was investigated. The results demonstrate that in patients with CRF in predialysis period the circadian rhythm of serum iPTH concentration is at least partially preserved. However, the effect of dialysis on serum C-terminal iPTH concentration showed a sharp progressive fall of the concentration during haemodialysis on polyacrylonitrile membranes. The study of the circadian rhythm of serum calcitonin concentration in CRF patients with the six hours intervals between blood sampling could not reveal changes which favour the opinion of the existence of circadian rhythmicity. In patients on haemodialysis during haemodialysis with cuprophan membranes a rise of serum calcitonin concentration was observed.

Urinary protein excretion in children from families with Balkan nephropathy

We studied the urinary excretion of total protein and five other proteins in urine samples from a total of 831 children and adolescents. The characteristics of the children were: (1.) they resided in areas where Balkan nephropathy (BEN) is endemic and also had family members suffering from BEN; (2.) they resided in areas where BEN is endemic, but the families had no members suffering from the disease; (3.) they lived in nonendemic settlements; (4.) they lived in the city of Nis. Urinary excretion of total protein (TP), albumin (ALB), alpha 2-macroglobulin (alpha 2m), transferrin (TF), IgG, and beta 2-microglobulin (beta 2m) were measured. This study showed that urinary excretion of beta 2m and albumin in children from endemic settlements and from families affected with Balkan nephropathy were not different from the control rural settlements. However, children residing in the city of Nis had significantly increased urinary beta 2m and albumin excretion, over 1.5 to 2.6 times the excretion in the other three groups, although excretion of either protein remained within accepted normal ranges in all groups. The increased excretion of beta 2m and albumin in children from the city of Nis could probably be related to the different growth conditions and/or the effect of toxic environmental factors. These data could serve as a reference base for future comparative studies of urinary protein excretion in children as well as in BEN populations.

Erythrocyte delta-aminolevulinate dehydratase measurements in Balkan endemic nephropathy

Balkan endemic nephropathy (BEN) is a chronic progressive kidney disease leading to renal insufficiency. The possible etiological role of some toxic factors was considered in this study by investigating the activity of erythrocyte delta-aminolevulinate dehydratase (ALA-D), an enzyme influenced by various environmental factors. We observed that ALA-D activity was markedly decreased in patients with BEN and in 32% of their healthy family members. Glutathione concentration was found normal in all the groups studied, however, it was possible to reactivate the enzyme in vitro by addition of exogenous glutathione. Percent activation was significantly higher in the groups with decreased ALA-D activity. Blood lead levels were within normal range. The results suggest a normal synthesis of ALA-D apoenzyme, and also the presence of some factors, environmental, metabolic, or genetic, which may affect the enzyme activity through binding to the reactive groups in the active center of this enzyme or by oxidation of the reactive groups. Additional studies are necessary to further elucidate the significance of decreased ALA-D activity in BEN and their healthy relatives.

[Activity of delta-aminolevulinate dehydratase and glutathione levels in the erythrocytes of patients with endemic nephropathy and in healthymembers of their families]

In a previous paper a markedly decreased activity of delta-aminolevulinate dehydratase (ALA-D) in patients with endemic nephropathy and in 24.6% of their healthy family members, was found. In this study the possible mechanisms of the decreased enzyme activity and the level of erythrocyte glutathione in patients and in healthy members from nephropathic families, were studied. We established decreased ALA-D activity in endemic nephropathy patients and in some healthy persons from their families. The normal concentration of erythrocyte glutathione was found in all groups. However, it was possible to reactivate the ALA-D enzyme in vitro by addition of exogenous glutathione. The obtained results suggested a normal synthesis of ALA-D apoenzyme and the existence of some factors whose effect upon enzyme activity was mediated through a binding to the reactive groups in the active centre of his enzyme or by oxidation of he reactive groups. Therefore, increased concentrations of sulfhydryl compounds, mostly of reduced glutathione are necessary for an optimal ALA-D activity.

delta-Aminolevulinic acid dehydratase activity in erythrocytes of diabetic patients

Erythrocytes delta-aminolevulinate dehydratase activity was assayed in 41 diabetic patients and 33 normal controls. It was found that in diabetic patients the erythrocyte ALA-D activity was lower than in controls, and the difference of the mean values was statistically highly significant (P less than 0.001). We found a significant negative correlation (r = - 0.846, P less than 0.001) between ALA-D activity and blood glucose levels. For this reason, using normal adult human whole blood haemolysates, it was investigated the effects in vitro of glucose and insulin on normal erythrocytic ALA-D. No significant difference in ALA-D activity was found in the presence of insulin. On the other hand, there was considerable decrease in the enzyme activity in the blood samples after glucose addition.

Effect of ethionine on gamma-cystathionase, homoserine dehydratase and cysteine desulfhydrase activities

The administration of ethionine results in a rapid and marked increase in rat liver cysteine desulfhydrase activity. However, this antimetabolite of methionine does not affect the hepatic levels of homoserine dehydratase and gamma-cystathionase.

Effect of trypsin, S-adenosylmethionine and ethionine on L-serine sulfhydrase activity

Trypsin causes an activation of serine sulfhydrase in the liver extracts from intact animals, but inhibits enzyme activity in the liver of ethionine treated rats. Trypsin also decreases an elevation of serine sulfhydrase activity caused by S-adenosylmethionine.