The activity of antioxidant enzymes and the content of uncoupling protein-1 in the brown adipose tissue of hypothyroid rats: comparison with effects of iopanoic acid

The activity of antioxidant enzymes, copper-zinc superoxide dismutase (CuZnSOD), manganese superoxide dismutase (MnSOD) and catalase (CAT), as well as that of the mitochondrial FAD-dependent alpha-glycerophosphate dehydrogenase (alpha-GPD) in the rat interscapular brown adipose tissue (IBAT) were studied after the treatment with methimazole (MMI) for three weeks or with iopanoic acid (IOP) for five days. Besides, the mitochondrial concentration of uncoupling protein-1 (UCP-1) and the activity of catecholamine degrading enzyme monoamine oxidase (MAO) in the IBAT as well as the activity of the catecholamine synthesizing enzyme, dopamine beta-hydroxylase (DBH) in rat serum were examined. Judging by the significantly enhanced level of serum DBH, which is an index of sympathetic activity, and that of IBAT MAO, the increase in MnSOD and CAT activities in the IBAT of hypothyroid (MMI-treated) rats seems to be due to elevated activity of sympathetic nervous system (SNS). However, CuZnSOD activity is not affected by SNS. On the contrary, IOP, which is a potent inhibitor of T4 deiodination into T3 producing "local" hypothyroidism, did not change either SNS activity or activities of IBAT antioxidant enzyme. However, both treatments significantly decreased IBAT UCP-1 content and alpha-GPD activity suggesting that the optimal T3 concentration in the IBAT is necessary for maintaining basal levels of these key mitochondrial parameters.     

Ontogenetic profile of ecto-ATPase activity in rat hippocampal and caudate nucleus synaptic plasma membrane fractions

An ontogenetic study of ecto-ATPase activity and the content of enzyme proteins was assessed in the caudate nucleus and hippocampal synaptic plasma membranes isolated from rats at various ages (15, 30, 90, 180 and 365 days). The ontogenetic profile revealed that the enzyme activities in both brain areas were the highest on day 30 and 365, while the ecto-ATPase protein abundance was the highest on day 15 after birth. Possible explanation for obtained ontogenetic profile and the discrepancy between activity and abundance may reside in the fact that ecto-ATPase during development could exert additional roles other than those related to metabolism of ATP. It is likely that ecto-ATPase, regulating the concentration of ATP and adenosine in synaptic cleft, has important role in the processes of brain development and aging.     

Effects of estradiol benzoate and progesterone on superoxide dismutase activity in the thymus of rats

The activity of mitochondrial superoxide dismutase (MnSOD) and cytosol superoxide dismutase (CuZnSOD) was measured in corresponding subcellular fractions prepared from the thymi of intact and chronically gonadectomized (GX) rats of both sexes, as well as of GX male and female rats injected subcutaneously with a single dose of 5 microg estradiol benzoate (EB) and/or 2 mg progesterone (P). Animals were sacrificed 2 h or 24 h following hormone treatment. In the females, the activity of MnSOD in the thymus was stable during the estrous cycle and did not change after ovariectomy. Treatment of GX females with estradiol benzoate resulted 2 h later in a significant elevation of MnSOD activity, whereas 24 h later the activity returned back to control values. On the other hand, treatment of GX females with progesterone had no effect on the MnSOD activity. However, combined hormone treatment, in which EB injection preceded progesterone injection by one hour, enhanced the effect on MnSOD activity similar to that of estradiol benzoate alone. The activity of CuZnSOD in cycling rats was increased in proestrus, whereas removal of the ovaries kept the values at low diestrus and estrus levels. Contrary to MnSOD, CuZnSOD activity did not change after EB treatment of GX females, while progesterone increased the enzyme activity at 2 h and 24 h after hormone treatment. However, combined EB+P treatment proved to be ineffective. In the males, neither MnSOD nor CuZnSOD activity was affected by the removal of testes or by progesterone treatment of GX animals. Only EB injection to GX rats significantly increased CuZnSOD activity 24 h later.     

Benign epithelial gastric polyps--frequency,location, and age and sex distribution

Prospective investigation has been undertaken with the aim to study the frequency, location and age and sex distribution of various histological types of benign gastric epithelial polyps. Histological type--adenomatous, hyperplastic and fundic gland polyps--was diagnosed on the basis of at least three histological samples taken from the polyp. Biopsy samples were also taken from the antrum and the body of the stomach so that gastritis could be graded and classified, and the presence of H. pylori could be determined by histology. All 6,700 patients, who had undergone upper gastrointestinal endoscopy in a one-year period, participated in this study. Among them 42 benign gastric epithelial polyp were found in 31 patients: adenomatous gastric polyps in 7 patients, hyperplastic gastric polyp in 21 and fundic gland polyp in 3 patients. All patients with hyperplastic polyps had chronic active superficial gastritis, whereas most of the patients with adenomatous polyps had a chronic atrophic gastritis with high prevalence of intestinal metaplasia. Among 21 patients with hyperplastic gastric polyps, 16 (76%) patients were positive for H. pylori infection in contrast to only 2 patients (29%) with adenomatous gastric polyps and 1 patient (33%) with fundic gland polyp. Presented data indicates that hyperplastic gastric polyps are the most common and they are associated with the presence of chronic active superficial gastritis and concomitant H. pylori infection. Adenomatous polyps are rarer and they tend to be associated with chronic atrophic gastritis and intestinal metaplasia. Fundic gland polyp is the rarest type of gastric polyps.     

Amniotic membrane transplantation for ocular surface reconstruction in neurotrophic corneal ulcera

The purpose of this study is to analyze clinical experience about the effects of human amniotic membrane transplantation in eyes with neurotrophic ulcers. In 11 eyes the application of amniotic membrane was performed since January 1999 because of neurotrophic ulcers. The follow up period was longer than 12 months: 19.7+/-6.0 months. The average healing period after the surgery was 1.6+/-0.6 weeks. All corneas were fluorescein negative even 12 months after operation. Visual acuity after the transplantation was similar to the one before the surgery in 8 eyes. In 3 eyes the visual acuity after the surgery was better than before. Amniotic membrane transplantation can be considered an effective alternative for treating persistent epithelial defects such as neurotrophic ulcers. It has some advantages over corneal transplantation: a relatively simple procedure, no allograft rejection and it could be particularly beneficial in countries where cornea shortage is apparent.     

Epidemiology of malignant pleural mesotheliomas in Croatia in the period from 1989 to 1998

Malignant pleural mesotheliomas are rare tumors. Their occurrence is often associated with the exposure to asbestos. Asbestos is widely used in various industries as well as for many types of products in everyday use. In Croatia in the period from 1989 to 1998, the rate of incidence was 0.4-1.1/100,000. The highest rate of incidence was in the Districts of Istria (2.9) and Split-Dalmatia (2.5). It is more frequent among males than among females with a ratio of 3.2:1. It rarely occurs before the age of 40 and most of the patients suffering from the disease are more than 65 years old. About 12% of mesotheliomas metastasize into regional lymph nodes and 17% of them into distant organs. The disease unavoidably leads to death and, according to the data obtained in Croatia in the period from 1989 to 1998 the mortality and incidence are very close.     

Pleomorphic vulvar leiomyoma with local invasive behavior

A case of pleomorphic leiomyoma in Bartholin gland's area in a 26-year-old woman is reported. After diagnostic treatment, primary excision was done. A large, solid tumor 10 x 7.5 cm was extirpated. The tumor showed locally invasive behavior, which suggested a malignant tumor of Bartholin gland, because of it's localization and outlook. Pathohistological examination and immunohistochemical reactions proved that it was a mesenchymal tumor of smooth muscle origin with marked polymorphism, without mitosis, with a myxoid stroma and with biological aggressivity, and the possibility of local recurrence. Thus, a second more radical surgical procedure, was performed. In the excised tissue, no residual tumor was found and all lymph nodes were negative.     

Symptomatic epilepsy associated with intracranial calcifications in children with acute lymphoblastic leukemia (ALL)

Acute and long-term sequels of central nervous system (CNS) prophylaxis with irradiation and intrathecal chemotherapy in children suffering from acute lymphoblastic leukemia (ALL) include vasculopathies, leucoencephalopathies, intracranial calcifications, intellectual and neurological impairment. We report two children at the age 5 and 8 years who manifested partial motor or complex seizures and intracranial calcifications 2-4 years after the diagnosis of ALL had been established. The occurrence of these disorders was much earlier than reported in the literature. Both children received prophylactic CNS treatment with irradiation and intrathecal methotrexate (MTX). Their brain CT scans and EEG had been normal before the first epileptic seizure was registered. Children are now seizure free on carbamazepine, and a boy with complex partial and myoclonic seizures is also on valproate and vigabatrine. Symptomatic epilepsy associated with intracranial calcifications and persisting EEG changes might occur as side effects of ALL treatment.