Lege Artis Medicinae

[The prerequisite of T cell recognition: antigen processing and presentation]

RAJNAVÖLGYI Éva1

MAY 26, 1993

Lege Artis Medicinae - 1993;3(05)

[Multiple regulatory mechnanisms are activated wit hin the immune system to maintain the homeostasis of the organism. A key element of these processes is the specific recognition of antigens mediated by T and B lymphocytes. This is the basis of clonal selection and antigen specific activation of the immune system (LAM 1991. 1(18):1308–1314.) which results in the most efficient elimination of the antigen. T cells play a predominant role in the discrimination of self and non-self structures. Antigen specific activation of T cells results in the expression of cell surface molecules and in the production of different lymphokines of high biological activity, which define the possibilities for cell to cell interactions and influence the function of different cell types affecting the outcome of the immune response. The appropriate activity of functionally distinct T cells enables the most efficient mobilization of effector mechanisms leading to the elimination of the antigen without destroying self components. In order to exert their regulatory and effector functions they require a well regulated collaboration with antigen presenting cells. This review summarizes our present knowledge on the intracellular degradation and transportation pathways occuring on in antigen presenting cells determining the antigen specific functions of T cells. It is well established that these events influence the efficacy or protection against pathogens and have a basic influence on the normal or pathological outcome of autoimmunity.]

AFFILIATIONS

  1. Eötvös Lóránd Tudományegyetem Természettudományi Kar Immunológiai Tanszék, Göd

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Lege Artis Medicinae

[Thoughts on radical hysterectomy]

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[Radical hysterectomy and pelvic lymphade nectomy have been used for the treatment of carcinoma of the uterine cervix in most Western countries for decades. These surgical procedures, however, have rarely been advocated in Hungary. Advantages and disadvantages of radical hysterectomy with pelvic and paraaortic lymph node dissection are discussed. Emphasis is placed on patient selection. It is the author's view that radical surgery does have a place in the management of cervical cancer. The patient should be informed about the possible treatment modalities available such as radical surgery, radical radiation therapy or a combination of surgery and irradiation, and she should be involved in the decision making process. Radical hysterectomy with pelvic lympha denectomy is a major operation with potentially significant intraoperative and postoperative complications. A dequate surgical skill and sufficient experience are required and this procedure should be regularly practiced. For these reasons, it is probably best performed in cancer centres.]

Lege Artis Medicinae

[The Social Security Health Insurance Fund's Mental Hygiene Board of Trustees]

[The Board of Trustees of the Social Insurance Health Insurance Fund for Mental Hygiene invites applications for the implementation of mental health promotion and mental hygiene programmes from the fund allocated by Parliament from the 1993 social insurance budget, pursuant to Act LXXXIV of 1992. ]

Lege Artis Medicinae

[The role of computed tomography in tumor staging of bronchogenic carcinoma]

HEILER Zoltán, PÁLFFY Gyula, KOSTIC Szilárd, MONOSTORI Zsuzsanna, REPA Imre

[Operability of lung cancer is based on the size and local extension of the tumor as well as the presence of lymph node and distant metastases. Agreement and disagreement between CT and surgical tumor staging was investigated for 197 cancer patients after surgery. Sensitivity and specificity of CT prediction ranged 57–93% and 71–100% ac cording to tumor stadium. CT diagnosis has been relatively unreliable in describing tumor propagation along the pulmonary veins (less frequently arteries) towards the atrium and in recognizing a discrete tumor invasion of the mediastinum. Local thickening of the parietal pericardium, and small pericardial effusion have been considered as indirect signs of pericardial tumor infiltration. MR examination have been found to be a supplemental technique for assessing tumor spread to the great vessels of the mediastinum. The authors believe on the results that new techniques, such as MR angiography and indirect CT signs will help in making a more accurate preoperative diagnosis of lung cancer.]

Lege Artis Medicinae

[Report on gastroenterological endoscopic activity in Hungary in 1992]

NAGY György, JUHÁSZ László

[At the request and on behalf of the Endoscopic Section of the Hungarian Gastroenterological Society, we have compiled the main data of the Hungarian endoscopic activity in 1992. We received responses to our questionnaire from 117 endoscopic laboratories and one private endoscopic practice. The responses received were summarised in a table.]

Lege Artis Medicinae

[Heparin-Aspirin Reperfusion Trial]

MATOS Lajos

[Treatment efficacy was first assessed 7-24 hours after the start of rt-PA infusion: at this time, the coronary artery leading to the infarct was patency in 82% of patients also receiving heparin therapy, compared to 52% of patients receiving aspirin supplementation (p<0.0001). Vessels that were patency-free at the first test remained open in 80% of those also treated with heparin after one week, the same was 95% in those treated with aspirin (non-significant). Bleeding was observed in 18 patients in the heparin group and 15 in the aspirin group. Ischaemic events were observed in eight cases in the former group and in two cases in the latter group - these were not statistically significantly different. The mortality rate was 1.9% in the heparin group and 4.0% in the aspirin group. ]

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Clinical Neuroscience

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