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J Barta

Publications and source records attributed to J Barta.

13 recordsLinked to original sources
PubMed2006

Release of alpha-tocopherol from antioxidative low-density polyethylene film into fatty food simulant: influence of complexation in beta-cyclodextrin.

The release of alpha-tocopherol from two formulations (with and without complexation with beta-cyclodextrin) of low-density polyethylene (LDPE) film was examined. Specific migration studies were performed at 7.0 +/- 0.5 degrees C using plastic bags filled with 95% ethanol as a fatty food simulant. The amount of complexed and free (non-complexed) alpha-tocopherol migrating into the food simulant was followed by high-performance liquid chromatography (HPLC). It was concluded that complexation with beta-cyclodextrin had a significant effect on the release rate of the antioxidant. Using a mathematical model for the description of the migration, a decrease in diffusion coefficient (D) of one order of magnitude was calculated in the case of complexed alpha-tocopherol compared with the free form. Total migration of alpha-tocopherol from both films was observed, meaning that the partition coefficient of tocopherol was not influenced by incorporation with cyclodextrin. Thus, complexation might be the key to a long-lasting antioxidative effect of such kind of active packaging.

Antioxidants↗
PubMed2005

Propolis solution for the treatment of chronic vaginitis.

OBJECTIVE: To evaluate the efficacy of 5% propolis solution in recurrent vaginitis. METHOD: Fifty-four patients with recurrent vaginal infections having undergone at least one cycle of antibiotic treatment were instructed to apply a 5% aqueous propolis solution as a vaginal douche for seven days. Vaginal smears and specific symptoms were evaluated at baseline and 14 days after treatment. Long-term well-being was assessed by telephone interview six months after follow-up. RESULT: At the follow-up, the vaginal smears of 41 patients (75.9%) had improved. Forty-seven patients (87%) reported reliefs concerning at least one complaint. Associated improvement of smear and well-being was observed in 36 women (66.7%). After 6 months, 33 patients (61.1%) were satisfied with their condition without having undergone further treatment. CONCLUSION: Propolis may have a role as an alternative treatment for chronic vaginal infection.

Anti-Infective Agents↗
PubMed1999

Circadian blood pressure changes and cardiac abnormalities in IgA nephropathy.

The absence of diurnal blood pressure rhythm is characteristic of patients with chronic glomerulonephritis already before they develop hypertension. The prognostic importance and possible target organ-damaging effect of the absence are unknown. Simultaneously, 24-hour ambulatory blood pressure monitoring and echocardiographic investigations were done in 12 normotensive and 38 hypertensive IgA nephropathy patients. The hypertensive patients were treated with either angiotensin-converting enzyme inhibitor (ACEI) alone or in combination with a non-dihydropyridine calcium channel blocker. The absence of a night-time blood pressure reduction was frequent in both groups (5/12 vs. 20/38). In the hypertensive patients, blood pressure and left ventricular mass index were higher (124.6 +/- 23. 3/81.2 +/- 15.3 vs. 106.6 +/- 33.4/67.4 +/- 21.8 mm Hg, p < 0.001, and 124.1 +/- 46.2 vs. 89.2 +/- 45.6 g/m(2), p < 0.01). Diastolic left ventricular function was better in normotensive patients, in whom E wave/A wave ratio (E/A) and decelaration time values correlated closely with the diastolic diurnal index (E/A, r = 0.86, p < 0.01; DT, r = -0.70, p < 0.01). In the hypertensive patients, both the left ventricular wall thickness and diastolic function were significantly related to nighttime blood pressure and diurnal index values, but there was no relationship with daytime blood pressure. In conclusion, in IgA nephropathy patients there are mild cardiac abnormalities before they develop hypertension, the abnormalities bearing the closest correlation with the decrease in diurnal blood pressure rhythm. These data suggest the inefficacy of ACEI and calcium channel blockers in treating nighttime hypertension and in reestablishing diurnal rhythm. These phenomena are of great importance in the development of left ventricular hypertrophy and diastolic malfunction.

Adolescent↗
PubMed1996

[Does tonsillectomy cause any change in long-term course of IgA nephropathy?].

Tonsillectomy seems to be a logical step in IgA nephropathy owing to the frequent tonsillitis before the beginning and the acute exacerbations of the disease. The usefulness of tonsillectomy is questionable because there are only few and short-term follow-up data after it. We followed up 35 kidney biopsy proven IgA nephropathy patients (25 men and 10 women) for an average of 12.2 yrs (range 7-32) after tonsillectomy. The values of endogenous creatinine clearance, serum creatinine, hematuria and proteinuria were compared at regular intervals during a follow-up with those obtained before tonsillectomy. We considered more than 12,000 data using 2 tailed t test. We found that proteinuria started to decrease significantly already 6 months after tonsillectomy (1.40 +/- 0.27 g/day before tonsillectomy vs 0.92 +/- 0.25 g/day after it, p < 0.05) and was significantly lower under follow-up. The tendency in microhematuria was similar (70.5 +/- 35.0 million RBC/12 hours before and 14.0 +/- 6.5 million RBC/12 hours 6 months after tonsillectomy, p < 0.0001). Furthermore, tonsillectomy stopped gross hematuria appearing in the acute exacerbation of the disease in more than two-thirds of patients. Creatinine clearance did not change in the first 2 years after tonsillectomy, however, from 2.5 years after it is significant slow and continual decrease started (117.0 +/- 9.8 ml/min before and 106.2 +/- 10.8 mil/min 2.5 yrs after tonsillectomy, p < 0.05). End-stage renal failure was detected only in 4 patients out of 35 after 10 years after tonsillectomy, in our non-tonsillectomised control group in 8 patients out of 40.

Adolescent↗
PubMed1996

[Relationship between intestinal permeability and antibodies against food antigens in IgA nephropathy].

Elevated antibody titers to food antigens and increased intestinal permeability in IgA nephropathy (IgA NP) suggest that these factors may be interdependent and play a role in the pathogenesis of the disease. In 1989 IgA and IgG antibodies against eight common food antigens were examined in the sera of 35 IgA NP patients and 12 controls using the ELISA method. Intestinal permeability was determined in 29 IgA NP patients and 20 controls using the 51Cr-EDTA test. Both examinations were carried out in 17 patients. Twenty-one patients allowed the intestinal permeability examinations to be repeated five years later. Compared with controls, significantly elevated IgA antibody titers against gliadin, soy, HAV (salt extracted antigens of oat flour) and ovalbumin were found. Intestinal permeability was significantly higher in IgA NP patients both in 1989 (3.86% +/- 0.29 vs. control, 2.72% +/- 0.23; p < 0.005) and in 1994 (4.57% +/- 0.63; p < 0.02) than in controls. A strong correlation was observed between the intestinal permeability and the IgA type of antibody titers against soy (p < 0.01; r = 0.72) and HAV (p < 0.02; r = 0.57). In patients without azotemia (serum creatinine > 150 mumol/l; n = 22) the decrease in creatinine clearance was significant only in the cases of increased intestinal permeability. On the basis of these data we assume that there is a connection between intestinal permeability and the production of IgA type antibody against food antigens in least a proportion of patients with IgA NP, and as a results of the lasting increase in intestinal permeability the production and the mesangial deposition of IgA immunocomplexes also increase.

Antibodies↗
PubMed1989

Effects of oral contraceptive and estrogen administration on plasma calcitonin in pre- and postmenopausal women.

Estrogen (E) therapy and administration of oral contraceptives (OC) reportedly increase plasma calcitonin (CT) concentrations in women, effects said to mediate in part the beneficial actions of E on bone. To further examine this theory, we tested the effects of three cycles of OC therapy in 12 young women, comparing them to 10 healthy women before and after three normal menstrual cycles. We also determined the effects of 3 months of E therapy (ethinyl estradiol, 20 micrograms/day, 25 of 30 days) in 14 healthy postmenopausal women, using a crossover design (studied after 3 months with and 3 months without E). We determined CT by radioimmunoassay (antiserum G-1701) in whole plasma (iCT) and silica cartridge extracts of plasma (exCT) after overnight fasting, after calcium (Ca) infusion (2 mg Ca/kg over 5 minutes), and during a normal day at 0800, 1200, 1700, and 2000 h. In no control study was there a significant diurnal change in iCT or exCT, and neither OC nor E therapy altered this. Similarly, OC administration did not affect basal CT levels or the normal iCT and exCT responses to Ca infusion. E therapy induced expected changes in serum Ca, phosphorus, and alkaline phosphatase and urinary Ca and cAMP excretion; basal and diurnal plasma exCT levels were decreased significantly, consonant with the decrement in serum Ca. E did not alter normal iCT and exCT responses to Ca infusion. Thus, administration of either OC or E has no stimulatory effect on CT secretion, which suggests that the beneficial actions of E on bone are not mediated through CT-induced inhibition of bone resorption.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Calcitonin secretion in postmenopausal osteoporosis.

Calcitonin deficiency has been implicated in the pathogenesis of accelerated bone loss, especially in postmenopausal osteoporosis. To investigate this issue, we studied 25 patients with untreated postmenopausal osteoporosis, 14 age-matched and sex-matched healthy controls (spinal bone mineral density greater than or equal to age-specific and sex-specific mean), and 5 women who had undergone total thyroidectomy. Each subject received an intravenous infusion of 2 mg of elemental calcium per kilogram of body weight over 5 minutes, to test the C-cell secretory reserve. We measured calcitonin by radioimmunoassay in whole plasma and in silica-cartridge extracts of plasma, the latter method providing greatly improved sensitivity and specificity for monomeric calcitonin. Basal immunoreactive calcitonin concentrations, whether measured in whole plasma or in extracts, were significantly higher in the subjects with osteoporosis (P less than 0.01) than in the healthy controls. The calcitonin secretory reserve, as assessed by calcium stimulation, was normal in the osteoporotic group but virtually absent in the thyroidectomy group. We conclude that postmenopausal osteoporosis is not associated with and does not result from calcitonin deficiency. On the contrary, excessive skeletal calcium release may stimulate calcitonin secretion in patients with the disorder.

Adult↗
PubMedDate not supplied

Nitric oxide in IgA nephropathy patients with or without hypertension.

Nitric oxide (NO) is claimed to have a role in the pathogenesis of immune-mediated glomerulonephritis and in the regulation of blood pressure (BP). NO rapidly converts to NO2-/NO3- which is excreted in the urine. We determined the daily NO2-/NO3- excretion in 26 IgA nephropathy (NP) patients and 20 healthy controls, recording the BP in each. There was no difference in NO2-/NO3- excretion between IgA NP patients and controls (999.1 +/- 66.8 vs. 1,051.2 +/- 53.0 mumol/day). The urinary excretion of NO2-/NO3- in IgA NP patients whose mean diastolic BP remained above 85 mm Hg in spite of antihypertensive therapy, was significantly decreased (n = 8; 734.38 +/- 87.83 mumol/day; p < 0.05). There was a significant inverse correlation between mean diastolic BP and urinary NO2-/NO3- (p < 0.006). NO2-/NO3- excretion decreased with aging (p < 0.01) in IgA NP patients, but not in controls. The fact that there was no difference between the urinary NO2-/NO3- excretion of IgA NP patients and controls argues against the idea that NO production in immune-mediated IgA NP can be increased. The decrease of urinary NO2-/NO3- in hypertensive and in older IgA NP patients may be correlated with the impaired NO production of the endothelium.

Adult↗