Bioimpedance spectroscopy (BIS) has been suggested for the assessment of fluid shifts between intracellular (ICV) and extracellular volume (ECV) during dialysis. The electrical tissue parameters are estimated by fitting a Cole-Cole model to the impedance data. Those parameters are used for the calculation of ICV and ECV with a fluid distribution model (FDM). We investigated whether postural changes cause artifacts in the volume data measured with a commercial BIS system. This is of importance at the beginning of dialysis, when the patient lies down for treatment. Volume estimations were performed during tilt table experiments with 11 healthy volunteers. Impedance spectra (5 to 500 kHz) were recorded for the total body as well as for body segments (leg and arm) during three phases: (1) 30 minutes resting in a supine position after standing; (2) 30 minutes 70 degrees head up tilt; and (3) a 30-minute resting period in a supine position. ECV and ICV were estimated with a commercially utilized FDM which is based on Hanai's mixture theory. A monoexponential function was fitted to the data for extracting the time constants and the extrapolated steady state values of the volume changes. The ECV and ICV data changed significantly during all three periods, that is, a steady state could not be reached within 30 minutes. During phase 1 the ECV decreased by 1.8 +/- 0.7%, in the tilt phase it increased by 3.8 +/- 1.1%, and in phase 3 it decreased again by 2.9 +/- 1%. The ICV increased by 3.6 +/- 2.4% during phase 1 and decreased by 6.8 +/- 5.1% during tilting; in phase 3 it increased by 4.6 +/- 1.7%. The time constants were 36.4 +/- 12.7 minutes (ECV) and 10.8 +/- 5.4 minutes (ICV) during phase 3. Segmental measurements revealed that the legs contribute significantly to the measured volume changes. The absolute volume changes in ICV and ECV differed significantly in all phases, and the same was found for the time constants during phases 1 and 3. From this discrepancy it is concluded that the measured volume changes are artifacts that are caused by extracellular fluid redistribution. Furthermore, it appears unlikely that the measured fluid shifts actually occur between ECV and ICV in the absence of osmotic changes in the body fluids. The validity of the method for a reliable assessment of volume changes during dialysis appears questionable, as dialysis-induced volume changes lie in the same range as the orthostatically-induced spurious volume changes.
Abstract-The aim of this study was to evaluate the effect of orthostasis on the time course of plasma adrenomedullin concentration. On 5 different days, normotensive subjects were randomized to undergo for 30 minutes either 12°, 30°, 53°, or 70°passive head-up tilt or to remain supine. Venous blood was collected from each subject in the supine position before tilting, at 3 and 27 minutes during tilting, and at 2 and 50 minutes after orthostasis. Plasma adrenomedullin increased significantly with tilt of Ն30°in a stimulus-dependent manner. Approximately half of the increase seen at 27 minutes occurred during the first 2 minutes of upright positioning; the maximum effect with 70°tilt was ϩ70%. Elevations in norepinephrine, epinephrine, aldosterone, plasma renin activity, vasopressin, heart rate, and mean arterial pressure were also significant. Hematocrit, blood density, plasma density, and plasma volume loss rose (PϽ0.05) at 53°a nd 70°tilt. Our results indicate that adrenomedullin may play an important role in stabilization of hemodynamics during passive orthostasis. In conclusion, plasma adrenomedullin rapidly increases with orthostatic challenge in a stimulus-dependent manner and also swiftly returns to baseline levels after the subject resumes the supine position. Key Words: tilt, head-up Ⅲ adrenomedullin Ⅲ barorereflex Ⅲ volume, plasma Ⅲ catecholamines T he 52-amino acid peptide adrenomedullin (ADM) is a potent vasorelaxant 1 and natriuretic 2 peptide. The strong relationship between plasma ADM and vascular tone functions in water homeostasis by increasing the glomerular filtration rate and natriuresis while lessening renal vascular resistance. 2,3 Additionally, ADM might function as an endothelium-derived relaxation factor and an autocrine or paracrine factor for vascular smooth muscle. 4 Until now, no data were available on changes in plasma ADM levels induced by orthostasis, which redistributes blood from central-to lower-body vascular beds and unloads cardiopulmonary receptors 5 ; this causes constriction of resistance and capacitance vessels, 6 in part through the action of vasopressin, angiotensin, and endothelin-1. 7,8 The present investigation was designed to test the hypothesis that plasma ADM is influenced by head-up tilting (HUT) in normotensive, euhydrated humans; to study the time course of ADM during and after HUT; and to quantify effects in relation to the intensity of orthostatic challenge. As ancillary information, hemodynamic and other endocrine as well as blood volume indicators were determined. The present study shows that ADM responds quickly and in a dose-dependent manner to HUT, and its concentration rapidly declines afterward.
Purpose: Stromal alterations are observed following preoperative systemic therapy in breast cancer. The aim of the present study was to analyze the qualitative and quantitative changes of representative tumor stroma proteins in the context of neoadjuvant therapy and the response of patients undergoing preoperative systemic therapy. Experimental Design: Fifty women receiving preoperative systemic therapy were evaluated for clinical and pathologic parameters. Clinical response was defined according to International Union against Cancer (UICC) criteria, whereas pathologic responses to preoperative systemic therapy were defined according to the Chevallier and Sataloff classifications. The expression of tenascin-C, syndecan-1, collagen IV, and smooth muscle actin proteins was investigated using morphometric analysis of immunohistochemical reactions. Quantitative reverse transcription-PCR was done to evaluate the mRNA expression level of syndecan-1 and tenascin-C. The data were compared with 20 breast cancer samples of patients not treated with preoperative systemic therapy. Results: According to UICC criteria, the expression levels of collagen IV were up-regulated in all preoperative systemic therapy^treated patients (P = 0.002). Collagen IV was up-regulated in the preoperative systemic therapy group in both Chevallier and Sataloff classifications compared with the control cases (P = 0.025 and P = 001, respectively). There were no significant differences in the expression of smooth muscle actin between the treated and nontreated groups. The syndecan-1 proteoglycan level was significantly down-regulated in the preoperative systemic therapy group (Chevallier classes P = 0.015, Sataloff classes P = 0.015). Tenascin-C was up-regulated in women with progressive disease (P = 0.005). Conclusion: We have observed that the stromal component of breast carcinomas following preoperative systemic therapy differs from the nontreated tumors, which can be evaluated with the analysis of the above mentioned proteins.
Egészségügyi Informatikai Fejlesztő és Továbbképző Intézet, BudapestBevezetés: A heveny szívizominfraktust elszenvedett betegek halálozására vonatkozó hazai adatok hiányosak. Célki-tűzés: A szerzők a Magyar Infarctus Regiszterben szereplő 8582 infarktusos beteg (4981 ST-elevációval járó myocardialis infarctus) adatainak elemzésével a kórházi, a 30 napos és az egyéves halálozás vizsgálatát tűzték ki célul. Budapest öt kerületében rögzítették a prehospitális haláleseteket. Módszer: A halálozás kockázati tényezőinek vizsgálatára logisztikus regressziós analízist végeztek, majd ellenőrizték a modell illeszkedését. Eredmények: A kórházi, a 30 napos, illetve az egyéves halálozás az ST-elevációval járó infarktusos betegcsoportban 3,7%, 9,5%, illetve 16,5%, a nem ST-elevációs betegcsoportban 4%, 9,8% és 21,7% volt. A nem ST-elevációval járó infarktus miatt kezelt betegek egyéves halálozása szignifi kánsan magasabb volt. A halálozás kockázati tényezőit vizsgálva az életkor, a Killip-stá-dium, a kórelőzményben szereplő myocardialis infarctus, stroke, valamint a diabetes bizonyult prognosztikus jelentőségűnek. A percutan coronariaintervenció mindkét típusú infarktusban nagyon jelentősen javította a betegek rövid és hosszú távú életkilátásait. Következtetések: A prehospitális halálozás igen jelentős volt, a 30 napon belül bekövet-kező események 72,5%-a kórházon kívül történt. Orv. Hetil., 2013, 154, 1297 Short and long term prognosis of patients with myocardial infarction Hungarian Myocardial Infarction RegistryIntroduction: Mortality data of patients with acute myocardial infarction are incomplete in Hungary. Aim: The aim of the authors was to analyse the data of 8582 myocardial infarction patients (4981 with ST-elevation myocardial infarction) registered in the Hungarian Myocardial Infarction Register in order to defi ne the hospital, 30-day, and 1-year mortality. To evaluate the prehospital mortality of myocardial infarction, all myocardial infarction and sudden death were registered in fi ve districts of Budapest. Method: Multivariate logistic regression was performed to defi ne risk factors of mortality and the model were assessed using c statistics. Results: The hospital, 30-day and 1-year mortality of patients with ST elevation myocardial infarction were 3.7%, 9.5% and 16.5%, respectively. In patients without ST elevation myocardial infarction these fi gures were 4%, 9.8% and 21.7%, respectively. The 1-year mortality of patients without ST elevation was higher than those of with ST elevation and the difference was statistically signifi cant. Age, Killip class, diabetes mellitus, history of stroke and myocardial infarction were independent predictors of death. Coronary intervention improved the prognosis of patients with myocardial infarction signifi cantly. Conclusions: The rate of pre-hospital mortality was considerably high; 72.5% of 30 day mortality occurred before admission to hospital. Orv. Hetil., 2013, 154, 1297-1302
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