EPIDEMIOLOGICAL REGISTRY OF NEUROENDOCRINE TUMORS IN BULGARIA--A PILOT SURVEY.

The National registry of patients with neuroendocrine tumors (NET) in Bulgaria was established in 2013 as a joint initiative of the Bulgarian Surgical Society and the Institute for Rare Diseases. The register aims to explore the epidemiology of NET in Bulgaria, as well as the different diagnostic and treatment approaches for the disease throughout the country. This the first of its kind retrospective study of NET in the country is covering the period January 2012 - January 2013. A total of 127 patients with NET were identified. At the time of the survey the average age of patients with NET was 58.61 ± 15.59 years. The data show almost equal distribution between the genders with a slight predominance of women. The largest relative part of NET is those of NET located in the gastrointestinal tract (54.10 ± 4.51%), followed by those located in the pancreas (12.30 ± 2.97%) and in the lungs (10.66 ± 2.79%). In 72.44 ± 3.96% of the patients a immunohistochemical diagnosis was performed. The study confirmed the leading role of the surgery method of the NET management. In 65.83 ± 4.33% of the patients a radical removal of the tumor was conducted, while the relative part of the undertaken partial resection was 7.50 ± 2.40%. A statistically significant association between the type of surgical treatment and during the follow-up of patients was found. An update of the information in the register will allow a more precise determining of the distribution and management of NET in Bulgaria.

Effects of testosterone and 17, beta-estradiol on the polyamine metabolism in cultivated normal rat kidney epithelial cells.

Ornithine decarboxylase (ODC) and diamine oxidase (DAO) are important enzymes involved in the metabolism of polyamines (putrescine, spermidine and spermine). The influence of testosterone (T) and 17, beta-estradiol (E2) on the activity of ODC and DAO was examined in cultivated normal rat kidney (NRK) epithelial cells. The results showed an increase in enzyme activities 4 hours or 12 hours after hormonal treatment. Both T and E2 led to a significant increase (1.6-fold) in ODC protein level as compared to the controls. Cellular concentration of spermidine and spermine increased (2.2- and 2.6-fold respectively) 4 hours after T addition. A higher levels in concentrations of putrescine (1.4-fold) and spermine (1.5-fold) 12 hours after E2 treatment were observed. These results suggest that the biosynthesis and terminal oxidation of the polyamines in NRK epithelial cells are androgen- and estrogen-mediated and depend on the hormonal sensitivity of the cells.

Androgenic sensitivity of polyamine-oxidizing enzyme activities in female rat tissues.

Effects of testosterone (10 micrograms/100g body weight) on polyamine-oxidizing enzyme activities in female rat uterus, liver and kidney were demonstrated. Testosterone-treated rats exhibited 2.07 fold (p < 0.002) higher uterine polyamine oxidase (PAO) activity and 1.93 fold (p < 0.02) higher diamine oxidase (DAO) activity, as compared to the controls. In the liver, testosterone caused an elevation in PAO (1.39 fold, p < 0.05), but not in DAO activity, whereas in kidney the hormone stimulated DAO (1.30 fold, p < 0.05), but not PAO activity. The effects observed suggest a possible role for testosterone in the modulation of polyamine levels in the female organs studied and especially in uterus.

Developmental aspects of polyamine-oxidizing enzyme activities in the mouse kidney. Effects of testosterone.

In the present study developmental patterns of renal polyamine-oxidizing enzymes polyamine oxidase (PAO) and diamine oxidase (DAO) in male and female ICR mice were demonstrated. The effects of testosterone (10 micrograms/100g body weight) on renal PAO and DAO activities were also studied. The differences between sexes in both PAO and DAO activities were most clearly expressed in the immature kidney. At the age of 20 days PAO and DAO activities were 1.52 fold (p < 0.01) and 1.75 (p < 0.02) respectively higher in male mouse kidney than in female. Maturational processes reflected in significant increases in polyamine-oxidizing enzyme activities mainly in female mouse kidney, comparable with the gain in the kidney wet weight. Our data show that testosterone is able to influence renal PAO and DAO activities in addition to the well-known stimulation of polyamine biosynthesis. The hormonal effects were sex and age dependent. The influence of testosterone on renal PAO activity was mainly age dependent. The slight stimulation of renal PAO activity observed in 20- and 50-day old mice, 24 h after testosterone administration, change with a decrease in the enzyme activity at the age of 70 days. The effects of testosterone on renal DAO activity were mainly sex dependent. Testosterone caused stimulation of DAO activity with a very close magnitude (nearly twice) in female mouse kidney, independently of the age of mice. In contrast, in male mice the hormone treatment resulted in a statistically significant increase in renal DAO activity at the age of 70 days (1.3 fold, p < 0.05) only. It could be suggested that our data indicate the different contribution of renal PAO and DAO in androgen regulation of polyamine levels, depending on sex and the stage of the postnatal development.

Interaction of sex hormones and cholesterol with monolayers of dipalmitoylphosphatidylcholine in different phase state.

Interactions of estradiol, progesterone, testosterone and cholesterol with dipalmitoylphosphatidylcholine (DPPC) monolayers at the air/water interface using Wilhelmy-Tensiometer were studied by measuring the change of the monolayer surface tension gamma (mN/m). In order to estimate the role of DPPC phase state on the deltagamma effects the experiments were carried out at three temperatures: 37 degrees C, 41.5 degrees C and 47 degrees C, since at 37 degrees C and 47 degrees C the formation of ripple gel Pbeta and liquid-crystalline Lalpha DPPC phases respectively were realized. Surface tension lowering capacity of the individual components at the air/water interface decreases in the order cholesterol>estradiol>progesterone>testosterone. The surface tension decrease of previously formed DPPC monolayer after addition of cholesterol and hormones follows the order cholesterol>>estradiol>progesterone approximately = testosterone. The higher activity of cholesterol and estradiol is interpreted by the existence of hydroxyl group in the steroid A-ring and hydrocarbon chain in the cholesterol structure and the same hydroxyl group in the estradiol, with possible formation of hydrogen bond between this group and the C=O group of the DPPC. It is shown that the existence of C-H chain in the molecular structure is stronger determinant than the OH group regarding the interactions with the DPPC monolayers. The very low capacity of progesterone and testosterone to interact with the DPPC monolayer is explained by the lack of the C-H chain and OH group in their structures. It was shown that the interaction forces of the steroids studied with DPPC monolayers were dependent on the DPPC phase state, being in any conditions stronger in the Lalpha (47 degrees C) than in Pbeta (37 degrees C) phase. At 41.5 degrees C more complex behavior of the components at the monolayers was observed. The obtained results could serve the concept of regulated entry of the steroid sex hormones into the cells with the participation of the lipid membrane components.

Effects of female sex hormones on polyamine-oxidizing enzyme activities and polyamine concentrations in immature rat uterus and liver.

17 beta-estradiol (E2) and progesterone (P) treatment of immature female rats (10 micrograms/100 g body weight) respectively resulted in 1.38-fold (p < 0.02) and 1.42-fold (p < 0.02) increase in the uterine polyamine oxidase activity, and 2.45-fold (p < 0.001) and 1.43-fold (p < 0.02) increase in the uterine diamine oxidase activity, as compared to the controls. E2 caused a 5-fold (p < 0.05) and a 1.36-fold (p < 0.05) increase in putrescine and spermidine concentration respectively in rat uterus. Increases of 1.7-fold (p < 0.02) and 1.6-fold (p < 0.05) in putrescine and spermine concentration were determined in the P-treated uterus, as compared to the controls. The spermidine/spermine ratio, which is regarded as an index of growth rate, was higher in the E2-treated uterus and lower in the P-treated uterus than in the control uterus. No statistically significant hormonal effects were estimated in the immature liver. The data reported suggest the possibility of an involvement of polyamine-oxidizing enzymes in the modulation of polyamine concentrations in rat uterus by the female sex hormones.

[The catabolism of polyamines]. / Katabolizum na poliaminite.

The important role of the natural polyamines putrescine, spermidine and spermine in the normal and pathological cell growth is the main reason for the active investigation of their metabolism. The essential catabolic reactions of polyamine interconversion and terminal oxidation as well as data for the catabolic enzymes and the regulatory mechanisms of their activities are reviewed. The importance of catabolic reactions for the maintenance of the optimal polyamine concentrations during the cell growth and differentiation is also presented. The role of the essential catabolic enzymes spermidine/spermine N1-acetyltransferase, polyamine oxidase and diamine oxidase in normal and pathological cell growth is discussed.

Distribution of polyamine oxidase activity in rat tissues and subcellular fractions.

The activity of polyamine oxidase (PAO) in rat tissues, and its subcellular distribution, were assayed using a simple polarographic method. The highest PAO activity was measured in the liver and the lowest in the skeletal muscle. In liver, kidney and uterus the highest specific PAO activity was found in the light mitochondrial fraction. PAO was not found in the microsomal fraction except in the kidney.

[Estradiol binding by serum proteins in the postmenopause of women with breast cancer]. / Sviazyvanie éstradiola belkami syvorotki v postmenopauze u zhenshchin s rakom molochnoi zhelezy.

It has been established by Scatchard's plots that in breast cancer women the association constant (Ka) and the number of receptor sites (N) at binding of estradiol to serum proteins are changed considerably as compared to those in clinically healthy persons (the control group) Ka is increased and N is diminished. A higher level of free serum estradiol was measured by RIA in breast cancer patients. Serum gel filtration in column showed a decrease in globulin binding and an increase in the level of the albumin-bound labeled ligand as compared to the controls.

[The importance of the prophylactic use of antibiotics with women undergoing elective cesarean section]. / Za smisula ot profilaktichnoto prilozhenie na antibiotitsi pri zheni, ponesli elektivno tsezarevo sechenie.

Postoperative infectious morbidity was described in two groups of low risk cesarean sections (CS). The frequency of postoperative infectious complications was 6.89% of women, who received penicillin for a period of 3 to 5 days, but 5.67% of women, who did not received antibiotics prophylactically. Data were presented, which showed also the economic insignificance of antibiotic prophylaxis (AP) in women with low risk CS. On the basis of the indicated data an inference was made that AP was of no clinical efficiency in women with low risk cesarean sections. The authors recommend restraint in AP of such women, in whom postoperative infectious inflammatory complications are anyway very rare.

[Cesarean section and postoperative infectious-inflammatory complications. II. A comparative evaluation of 2 methods for antibiotic prophylaxis in cesarean section]. / Sectio caesarea i sledoperativni infektsiozno-vuzpalitelni uslozhneniia. II. Sravnitelna otsenka na dva metoda na antibiotichna profilaktika [correction of diagnostika] pri sectio caesarea.

The authors compare two methods for antibiotic prophylaxis of infectious-inflammatory complications in cesarean section: 1. Widely distributed mass prophylaxis with penicillin and gentamicin and 2. selective prophylaxis with Azlocillin, performed after determination, of the degree of the risk. 233 cesarean section were included in the study, 122 of which were treated by the first method. 59 out of 11 cesarean sections were evaluated as such with high risk and respectively treated with Azlocillin, but 52 of the women with low risk were not treated with antibiotic. The results show the advantages and economic benefits of the selective antibiotic prophylaxis in cesarean section.

Effect of estradiol on RNA synthesis and nuclear protein phosphorylation in rat liver.

Experiments were made to study the effect of 17, beta-estradiol on the RNA synthesis and nuclear protein phosphorylation in the liver of sexually mature female albino rats: sham-operated, ovariectomized and hormone-treated after the ovariectomy (20 micrograms estradioldipropionate/100 g body mass). The rate of RNA synthesis is determined in vivo by the 3H-uridine incorporation in the acid-insoluble fraction, whereas the nuclear protein phosphorylation is determined in vitro by the incorporation of gamma-32 P-ATP in isolated cell nuclei. Increased RNA synthesis is found to occur under the effect of the hormone, which corresponds to the hormone's effect on the uterine cells. The hormone stimulates the nuclear protein phosphorylation--an effect which could be associated with the gene expression.

Effect of estradiol on the phosphorylation of rat liver ribosome proteins.

The effect of estradiol on phosphorylation with gamma-32P-ATP of ribosome proteins from polyribosome fraction, isolated from female rat liver is found out. Rats (180 g) used were: sham-operated, ovariectomized and treated after ovariectomy for 11 days with 20 micrograms 17 beta-estradiol-dipropionate per 100 g body weight. The estradiol deficiency after ovariectomy decreased phosphorylation, but the estrogenization of ovariectomized rats increases it twice. In vitro the hormone (1-2 mumol/l) [corrected] also stimulated ribosome protein phosphorylation. It is supposed that the hormone may take part in the regulation of protein synthesis in the translational region of the process.

[Cesarean section and postoperative infectious-inflammatory complications. I. A new method for assessing the degree of risk of infectious-inflammatory complications]. / Sectio caesarea i sledoperativni infektsiozno-vuzpalitelni uslozhneniia. I. Nov metod za pretsenka stepenta na riska ot infektsiozno-vuzpalitelni uslozhneniia.

After analysing the present practice and describing their experience in 111 caesarean sections, the authors present a new scoring test for evaluation of the degree of the risk from infectious inflammatory complications after caesarean section and implementation of selective antibiotic prophylaxis in accordance with the evaluation. An attempt is made to classify separate factors according to their significance for development of inflammatory complications during the post partial period. The results, schematized on table 1 and figure 1 in the article, illustrate the practical benefit from the test in the prophylaxis of infectious inflammatory complications after caesarean section.

[Effect of estradiol on the synthesis of DNA in the female rat liver]. / Vliianie éstradiola na sintez DNK v pecheni samok krys.

The effect of estradiol on DNA synthesis in hepatocytes was investigated for a study of the functional importance and mechanism of action of sex steroids in the liver. After administration of 17, beta-estradiol dipropionate at a dose of 20 micrograms per 100 g of body mass to ovariectomized albino female rats for 11 days the kinetics of incorporation of 3H-thymidine triphosphate in liver cell nuclei and chromatin was determined. A stimulating effect of the hormone on the tracer incorporation in the nuclei and chromatin was established. A similar tendency was noted in immature female rats. The tracer incorporation depends on the cytosol presence in the system. The rate of incorporation has been shown to increase under the influence of the liver cytosol of intact rats. In can be assumed that estradiol is involved in the regulation of liver DNA synthesis raising matrix activity and modulating cytosol factor activity.

Effect of estradiol on the protein synthesis in the female rat liver in vitro.

The incorporation of 14C-leucine in protein, as well as in aminoacyl adenylate and aminoacyl-tRNA (AA-tRNA) from the liver of mature female rats (controls, ovariectomized and treated after the ovariectomy with daily doses of 20 micrograms 17, beta-estradiol-dipropionate/100 g body weight for 11 days), was investigated under conditions of a cell-free protein-synthesizing system containing isolated microsomes and cytosol. The ovariectomy causes reduced incorporation of the label in protein and in AA-tRNA, while hormonal treatment compensates this decrease either partially or completely. Data are presented which suggest that the hormone probably increases the supply of macroergic components and free amino acids to the hepatocytes, and that it also increases the sensitivity to cycloheximide and tetracycline. It is assumed that estradiol participates in the regulation of the protein synthesis in the hepatocytes at the level of AA-tRNA synthesis.

Binding of cytosol 3H-17, beta-estradiol to cytosol receptors in the liver of female rats.

The article is a study of the specific binding of 3H-17, beta-estradiol to cytosol receptors in the liver of female, sexually mature albino rats: sham-operated, ovariectomized and treated after the ovariectomy with 17-beta-estradiol (in doses of 20 micrograms/100 g body weight for 11 days). The binding of the labelled hormone in the liver cytosol isolated from ovariectomized rats is considerably reduced compared with the sham-operated animals. In the cytosol from the liver of the estradiol-treated rats the formation of a hormone-receptor complex is substantially increased compared with the ovariectomized animals. It is assumed that the formation of estradiol-receptor complexes in the liver depends on the concentration of the cytosol receptors, which is determined by the concentration of oestrogens in the blood.

Effect of estradiol on DNA and protein synthesis in rat liver in vivo.

The article studies the effect of 17, beta-estradiol on the binding of cytosol estradiol-receptor complex with chromatin isolated from the liver of female albino rats (sham-operated, ovariectomized and treated after the ovariectomy with 20 micron hormone/100 g body weight for 11 days) and sexually mature male albino rats. Higher binding of the complex is found for the female animals compared with the males. Parallel experiments are made to study the incorporation of 3H-thymidine and 14C-glycine in vivo, in acid-soluble and acid-insoluble liver fractions of female rats, respectively, which is used as a basis for assessing the rate of DNA and protein synthesis. Ovariectomy induces considerable reduction of the binding of the estradiol-receptor complex with chromatin, as well as of the DNA and protein synthesis. Hormonal treatment of the ovariectomized rats is followed by substantial increase in the parameters investigated above the level measured in intact animals. The observed effects of the hormone on the liver correspond to the accepted view concerning the action of steroid sex hormones on their target organs.

[Triiodothyronine binding by the liver nuclei and mitochondria]. / Sviazyvanie triiodtironina iadrami i mitokhondriiami pecheni.

The binding of I125-triiodothyronine by male thyroidectomized rat liver nuclei and mitochondria in vivo and in vitro was studied. Labeled triiodothyronine was bound by the liver nuclei and mitochondria proteins. 90% radioactivity was bound by the nuclear nonhistone proteins. The binding of I125-triiodothyronine to the nuclei and mitochondria protein receptors was inhibited by unlabeled triiodothyronine and ICl. It is suggested that aromatic amino acids serve as the binding sites of the protein receptors, and that iodine atoms in the thyroid hormone molecules participated directly in the binding process.