Eva Šimáková

Influence of high cholesterol diet and pravastatin sodium on the initiation of liver regeneration in rats after partial hepatectomy.

OBJECTIVES Liver regeneration is influenced by cholesterol and 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA-reductase). HMG-CoA-reductase is a key enzyme for cholesterol synthesis. Recent studies have shown that inhibitors of HMG-CoA-reductase improve liver functions after 67% partial hepatectomy (PH). METHODS Male Wistar rats (W) and Prague hereditary hypercholesterolemic rats (PHHC) were used. Aqua pro injectione (AI) or pravastatin (prava; 1 mg/kg) was administered orally once daily. Group 1: W, standard diet (SD) + AI; group 2: W, SD + prava; group 3: W, cholesterol-enriched diet (chol) + AI; group 4: PHHC, chol + AI; group 5: PHHC, chol + prava. After 27 d, PH was performed in all groups. RESULTS Groups fed chol before PH had significantly higher liver triacylglycerol content (group 3: 25.8 +/- 2.6 mg/g of liver weight; group 4: 16.0 +/- 1.0 of liver weight; group 5: 22.0 +/- 1.0 of liver weight) than did the groups fed SD (group 1: 6.1 +/- 0.5; group 2: 5.9 +/- 0.7). Liver DNA synthesis after PH was significantly lower in chol-fed groups (group 3: 561 +/- 78; group 4: 472 +/- 92) than in SD-fed groups (group 1: 1645 +/- 574; group 2: 2935 +/- 1298), except the chol-fed PHHC given prava (group 5: 3230 +/- 527). CONCLUSIONS In prava-treated rats, the induction of HMG-CoA activity overcame the inhibitory capability of pravastatin. The induction of HMG-CoA-reductase activity had a stimulatory effect on the initiation of liver regeneration.

Bi-weekly epirubicin, etoposide and low-dose dexamethasone for hormone-refractory prostate cancer

Background: Recent studies have demonstrated the efficacy and favorable toxicity profile of chemotherapy regimens given at lower doses and frequent intervals. The aim of our study was to evaluate the efficacy and toxicity of a bi‐weekly chemohormonal regimen consisting of epirubicin, etoposide, and low‐dose dexamethasone (EED) in patients with hormone‐refractory prostate cancer (HRPC).

Mechanical treatment and autoclaving of middle ear ossicles from cholesteatomatous ears

Aim of the study: The authors present a prospective histomorphological study of middle ear ossicles, harvested from cholesteatomous ears, to evaluate for presence of residual cholesteatoma after mechanical treatment and short-time autoclaving.Materials and methodsSixty ossicles were used as specimens in this study. The ossicles were grouped as follows: Group A — ossicles stripped and burred using a fine diamond burr under microscopic control. Group B — ossicles autoclaved for 4 min at 134°C after mechanical burring under microscopic control.ResultsIn group A, 30 ossicles were histologicaly examined after mechanical treatment. The residual disease was found in one badly eroded ossicle. In group B, 30 ossicles were histologicaly examined after mechanical treatment and autoclaving. That treatment eliminated cholesteatoma in all cases. The difference of results in these two treatment methods was not statistically significant.ConclusionAuthors recommend using mechanical cleaning in cases of mildly eroded ossicles. In cases of badly eroded ossicles authors recommend to either apply a combination of mechanical and autoclaving treatment. The study proved that 4 minutes of autoclaving at 134°C after mechanical cleaning provides safe bone autografts.

Growth Curves, Measurement and Three-Dimensional Reconstruction in the Histopathology of Temporal Bones

The paper consists of three parts, in which the opportunities for measurement in histopathology of the temporal bone are shown. Measurement of size and distance (1D measurement) is used for determining the growth curves during the fetal period. Measurement of area (2D measurement) shows a difference in volume of mesenchymal tissue in the middle ear cavity between the groups with and without kidney pathology during the prenatal period. A computer 3D reconstruction of malformations of the middle and inner ears can be applied in understanding the pathology of the hearing organ. The first part concerns the application of measurements of size and distance to a set of 121 temporal bones from 71 fetuses. For evaluation, the following parameters were collected from the histological samples: the height and width of the stapes, the height of the vestibule, the length of the macula sacculi, the length of the macula utriculi, and the height and width of the cochlea. Regression analysis was applied to the data set to determine the relationship of the growth curves of particular structures. The data for growth curves from 36 aborted, presumably normal fetuses, are used. So the growth curves show the normal development of these structures. The Mitscherlich model was found to be the most satisfying for the growth curve in the fetal period. The amount of mesenchymal tissue in the middle ear (2D measurement) was determined after computer digitalization (Lucia) of the samples’ area of the middle ear cavity. Statistical tests confirmed a larger amount of this tissue in the group of samples obtained from fetuses with pathological kidney findings (agenesis of kidneys, Potter’s sequence), in comparison with a group of spontaneously aborted fetuses without kidney damage.The 3D computer reconstruction of the temporal bone, the third topic, was created using our own Medicus software written for the project. In a sample of bone without pathology, reconstruction enabled assessment of basic anatomical structures and two temporal bones show malformation of the stapes (VATER syndrome) and the cochlea (trisomy 21).

Histological Changes of the Middle Ear Ossicles Harvested during Cholesteatoma Surgery

BACKGROUND In the cholesteatoma surgery ossicles can be replaced to reconstruct middle ear function. It is important that these ossicles are free of squamous epithelium, to prevent residual disease. This study focuses on the histological findings of the malleus and incus harvested during cholesteatoma surgery. MATERIALS AND METHODS Eighty middle ears ossicles were examined in vivo and histologically to consider the relationship of cholesteatoma to ossicles, grade of bone destruction and invasion of cholesteatoma to deeper layers of bone. RESULTS Serious ossicular destruction was observed more frequently in incus compared to malleus (p=0.0065). Difference of ossicles destruction between children and adults was not significant (p=0.3032). Deep invasion of cholesteatoma into the vascular spaces or inner core of the bone was not observed. CONCLUSIONS Autograft ossicles from cholesteatomatous ears should not necessarily be rejected for reconstruction of the ossicular chain. Regarding the histological finding, the authors suggest mechanical cleaning of the ossicle surface to eliminate residual disease.

The influence of repeated blood withdrawals before surgery on clinical outcome.

The aim of this study was to find the influence of blood withdrawals and diet iron on elective surgery. Male Wistar rats (n=24) were divided: 1. group (SLD) ate standard laboratory diet (SLD), 2. group (FE) an iron enriched diet (FE) with one blood withdrawal after 9 weeks. 3. group (SLD-w) SLD and 4. group (FE-w) ate the FE diet; with 9 withdrawals once a week. The rats were sacrificed 18 hour after partial hepatectomy (PH) in the 10th week. Liver DNA synthesis (3H-thymidin - kBq/mg DNA) was performed. Serum hepcidin (pg/ml), iron concentration, respiratory burst of polymorfonucleares (RB, spontaneous; stimulated, %), count of blood cells were determined. FE-w had a higher (2.36±0.36) liver DNA synthesis after PH vs. SLD (1.21±0.49). Higher hemoglobin in erythrocytes (pg) was in FE-w and SLD-w vs. FE and SLD. PMN count in SLD-w, FE-w increased vs. SLD, FE. Hepcidin after PH decreased in SLD (78.0), FE (68.0), FE-w (97.0), but increased in SLD-w (217). Serum iron increased in SLD-w. RB after PH increased in FE-w (4.5; 47.6) vs. SLD (1.15; 29.1), FE (3.20;17.8), SLD-w (3.30;13.7). CONCLUSIONS The iron diet with stimulation of haematopoesis by withdrawals improves an organisms condition expressed as better response to elective surgery and better PMN functions.