Lege Artis Medicinae

[The role of steroid hormones in the protection against oxidative stress]

BÉKÉSI Gábor, FEHÉR János

FEBRUARY 20, 2001

Lege Artis Medicinae - 2001;11(02)

[The incidence of vascular diseases increases in postmenopausal women. This negative trend seems to be controllable favourably by hormone replacement therapy (HRT). Based on the free radical mediated mechanism of atherogenesis the authors try to find the reasons for these observations on the basis of their and others’ data. They consider the increase of activity and amount of neutrophil enzyme myeloperoxydase by certain steroid particulars one of the most important elements of the vasoprotective effect of HRT. This increase diminishes the production of superoxide anion by the inhibition of the NADPH-oxidase enzyme. The observation proved firstly by the authors, that the plasma levels of myeloperoxydase - and so the ability for the inhibition of superoxide anion production by neutrophils - decreases in elderly people, might explain the higher incidence of some free radical mediated illnesses in the elderly. The authors also give a short review of antioxidant effects of steroids in general.]

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[The importance of vitrectomy in the management of diabetic retinopathy in proliferative stage]

BERECZKI Árpád

[Vitrectomy is a closed microsurgical technique, by which intraocular tissue, blood and foreign bodies can be removed through a small incision in the pars plana with an automated suction-cutting device (vitrectom), while maintaining normal or slightly elevated intraocular pressure. This technique requires many accessory instruments (microscope, endoillumination, intraocular instruments, endolaser). The main application of vitrectomy is the treatment of severe complications in diabetes mellitus: diabetic retinopathy in the proliferative stage. Vitrectomy is indicated in diabetic retinopathy for the removal of intraocular bleeding and for the treatment of complications of diabetic proliferative vitreoretinopathy (recurring bleeding, tractional and rhegmatogenous retinal detachment). In the case of intraocular bleeding, early vitrectomy is better than delayed, providing good visus (V: 0,5) in 25% of all patients (based on literature data). In retinal detachment cases of tractional origin, surgery provides satisfactory visus for self-care in 2/3rd of all patients.]

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[„There should be someone to hold the hand of the dying!” Deep interviews on the difficulties of caring for the dying]

BOGNÁR Tamás, KOLOSAI Nedda, HEGEDÛS Katalin, PILLING János

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[Gastrointestinal stromal tumor]

GONDA Gábor

[Gastrointestinal stromal tumors were subject of much controversy in the last decades. This type of tumors was delineated from the leiomyoma - leiomyosarcoma group. GISTs show variable histological picture, moreover, they are capable of dual (neurogen and myogen) differentiation as it is proved by immunohistochemical and ultrastructural studies. These tumors have relatively good prognosis, only 10-30% of them is malignant, although it is difficult to predict their behaviour in a given case. The most reliable signs of malignancy - cytological pleoimorphism, high mitotic activity, proliferation index above 10 %, and aneuploid DNA content - are generally accepted. The treatment of choice is excision, but not enucleation. Radical surgery is not necessary, since lymph node metastasis is exceptionally rare. Further investigations revealed electronmicroscopical and immunohistochemical (CD 34, CD 117) similarities of tumor cells and interstitial cells of Cajal (ICC) located in the wall of the bowel. The results of these investigations led to the theory that cells of GIST and ICCs are of the same stem cell origin. Molecular genetic studies are also of great help in the differential diagnosis and in predicting the prognosis of GISTs. Mutations in the c-kit gene can not be detected in leiomyomas, so they are thougt to be specific for GISTs. Mutation of exon 11. of chromosome 4. is observed only in malignant GISTs.]

Lege Artis Medicinae

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GRÉTSY Zsombor

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Lege Artis Medicinae

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[After menopause, coronary disease and infarction become increasingly common in women owing to estrogen deficiency. Therefore, hormon replacement therapy (HRT) had been widely used to prevent these problems and manage postmenopausal symptoms. In 2002, a large, randomised, placebo-controlled study reported that HRT was accompanied by serious side effects and was not suitable for cardiovascular prevention. However, subsequent re-alanyses of the data of this study and new studies in the past 10 years suggest that in women younger than 60 years and if started within 10 years after the menopause, HRT has a number of advantages and very few disadvantages. It substantially improves quality of life, while the absolute risk of side effects is small, and HRT is suitable for the primary prevention of coronary diseases. I summarise the cardiovascular aspects of menopausal hormone therapy, in order to help the necessary paradigm shift in this matter.]