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Plasmatic [corrected] factor XIII reduces severe pleural effusion in children after open-heart surgery.

Chylous effusions frequently occur after cardiac surgery due to severe damage to the lymphatic system, thus indicating that the insertion of a chest tube may be necessary. Factor XIII (FXIII) is discussed as being essential for wound healing. The aim of this retrospective study was to evaluate whether the application of a single dose of FXIII results in a reduced amount of pleural effusion, leading to an earlier release of patients from the hospital. The cases of 40 children with severe chylous effusions after open-heart surgery were examined. Twenty patients received FXIII and were compared to 20 age- and weight-matched patients who did not receive FXIII. Major parameters included the amount of effusion before and 1 and 3 days after the application of FXIII; the duration of chest tubes; the total amount of fluid loss via drainage; and the period of hospitalization. FXIII levels in plasma showed an inverse correlation with fluid loss. After application of a single dose of FXIII, a significant reduction of pleural effusion within the first 24 hours was detected. However, no difference was observed between the two groups when comparing the total amount of pleural effusions within the first 72 hours. Finally, the duration of hospitalization did not differ between the FXIII-treated and the control group. A single application of FXIII rapidly reduces the amount of chylous effusions in the early period after open-heart surgery. This effect is detectable only for 24 hours after the treatment and does not alter the further clinical outcome. Prospective clinical trials are warranted to determine if repeated application or a higher dose of FXIII may improve the clinical outcome of chylous leakages in children after open-heart surgery.

Case-Control Studies↗

Correction factors of 3H-beta-self-absorption for quantitative autoradiography of different cell types in the brain of pre- and postnatal mice.

Interferometric and morphometric studies were performed on seven types of brain cells of deparaffinised and Feulgen-stained brain sections of pre- and postnatal mice in order to find out to what extent 3H-beta-self-absorption factors (c.f.s) of karyoplasm and perikaryal cytoplasm change as the animals' age increases. This is important when comparing grain numbers of different cell types among mice of different age in quantitative autoradiographic studies after application of tritium-labelled substances. While optical path differences (o.p.d.s) of euchromatin and cytoplasm decreased in large neurons postnatally, heterochromatic o.p.d.s remained more or less unchanged. The fraction of euchromatin (fEu) and heterochromatin (fHe) changed specifically in relation to cell type with increasing age, i.e. mostly heterochromatin increased postnatally. Within a given age, c.f.s, calculated from o.p.d.s, fEu and fHe, varied up to a maximum factor of 2.16 for karyoplasm and a factor of 1.19 for cytoplasm between different cell types. A significant decrease of c.f.s postnatally was found only for the cytoplasm of cortical and hippocampal pyramidal cells and for cerebellar Purkinje cells. The c.f.s of karyoplasm remained more or less unchanged with increasing age of the mice. The calculation of relative c.f.s makes these c.f.s applicable for every other autoradiographic study using 3H-labelled substances.

Animals↗

Influence of R-wave amplitude on exercise-induced ST depression: need for a "gain factor" correction when interpreting stress electrocardiograms.

Does 2 mm of ST depression induced by exercise have the same clinical significance in a patient with a 30-mm R wave as a patient with a 10-mm R wave in the same monitored lead? To answer this question the exercise responses of 85 patients were compared by 2 quantitative methods of assessing myocardial ischemia. A computer-derived treadmill exercise score, based largely on the characteristics of exercise-induced ST-segment depression, was compared with a thallium exercise score. Both scores correlated well over a wide range of values (r = 0.71, p less than 0.001). Then, the treadmill exercise score was corrected (by adjusting the magnitude of the ST depression to a standardized R-wave amplitude of 12 mm in V5 and 8 mm in aVF) to determine if this would improve its correlation with the thallium exercise score. The patients were separated into 2 groups by R-wave amplitude: 53 had an RV5 of 9 to 17 mm and 32 had an RV5 less than 9 or greater than 17 mm. Correction of the treadmill exercise score for R-wave amplitude did not change the slope and intercepts of the regression line for patients with an RV5 amplitude of 9 to 17 mm, but did for those with an RV5 amplitude less than 9 or greater than 17 mm. In this latter group, R-wave correction changed the regression line from one that differed significantly from that of patients with less extreme RV5 voltage to one that was indistinguishable from it. Correction of the treadmill exercise score also increased the correlation coefficient from 0.54 to 0.68 in this group.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiography↗

Monte Carlo calculations of calibration and geometry correction factors of a radionuclide calibrator.

The activity of radioactive pharmaceuticals administered to patients in nuclear medicine is usually determined using well-type high-pressure ionization chambers. For the Bqmeter chamber (Consortium BQM, Czech Republic) a Monte Carlo model was created using the MCNP4C2 code. Basic chamber characteristics for two sample containers of various geometry (a vial and an ampoule) were calculated and compared with measurements. As the pharmaceuticals are often measured in various syringes, the chamber response for samples in syringes was also studied.

Algorithms↗