DEFINITION OF MIXING RATE OF INDICATOR BY INDICATOR DILUTION METHOD: EVALUATION OF RELATIONSHIP BETWEEN MIXING RATE OF INDICATOR AND CARDIAC OUTPUT DETERMINATION

It is generally agreed that complete mixing of the indicator is one of the most important factors of the indicator dilution method, however, no clear definition of the mixing state has been established. We established a formula for the mixing rate of the indicator by the indicator dilution method, using the concept of entropy in the information theory, and compared the mixing rate of indocyanine green in one mixing chamber (left ventricle) with that in the two mixing chamber system (including the aortic system). The mixing rate of the indicator (M) is shown as M(%)=100 H/Hcm -100 (lk Σn i=1 Ci log Ci +log k) (l & k: correction factors in each dye dilution curve, C: mean concentration of the indicator in the region).Left heart and aortic catheterizations by retrograde femoral and carotid artery approach were performed in five anesthetized dogs. Simultaneous dye dilution curves were recorded at the aortic root and at the bifurcation of the abdominal aorta, following the injection of indocyanine green (2.5 mg/lml of indocyamine green for each injection) by impulse into the left ventricle at the endsystole, triggered on the R wave of ECG, using the automatic injector devised by the authors. Twenty-five pairs of dye dilution curves were obtained by simultaneous recording in the aortic root and the abdominal aorta under several hemodynamic conditions, and the cardiac output, mean circulation time and the mixing rate of the indicator were determined.The mixing rate of the indicator obtained in the aortic root (mean±SE: M=78.7 ± 3.43%) was observed to be significantly greater (P<0.01) than in the abdominal aorta (mean ±SE: M=70.0±3.51%).Taking the mixing rate of the indicator into consideration, the cardiac output determination by the indicator dilution method is more sensitive to the changing hemodynamic conditions when determined in the aortic root than in the abdominal aorta

Involvement of estrogen receptor Beta in the induction of polyovular follicles in mouse ovaries exposed neonatally to diethylstilbestrol.

International audienceNatural and synthetic estrogens, Including diethylstilbestrol (DES), given during the critical period of newborn life Induce abnormalities in ovaries of mice. Induction of polyovular follicles (PFs) containing two or more oocytes in a follicle is one example. In this study, the involvement of estrogen receptor subtypes ERalpha and ERbeta in induction of PFs by neonatal treatment with DES was analyzed by using ERalpha knockout (alphaERKO) and ERbeta knockout (betaERKO) mice. Ovaries of mice injected with 3 microg DES for 5 days from the day of birth were examined histologically from 10 to 60 days of age, and the expression of genes involved in folliculogenesis was analyzed by real-time quantitative PCR. The PF Incidence (percent of PFs per 100 follicles greater than 50 microm in diameter) in the ovary of alphaERKO mice treated with DES was not different from that in the DES-treated wild-type mice. However, neonatal DES treatment did not increase the PF incidence in betaERKO mice, suggesting that PFs were induced by DES through ERbeta but not ERalpha. The expression of bone morphogenetic protein 15, growth differentiation factor 9, inhibin-alpha, Müllerian inhibiting substance, and other genes in the ovaries of DES-treated betaERKO mice was not different from that in the ovaries of DES-treated wild-type mice. These results indicate that ERbeta but not ERalpha is essential for DES to Induce PFs in mice

Arterial remodeling patterns before intervention predict diffuse in-stent restenosis An intravascular ultrasound study

AbstractObjectivesThe aim of this retrospective study was to determine the predictors of diffuse in-stent restenosis (ISR) among the lesions causing the first ISR by intravascular ultrasound (IVUS) studies.BackgroundAlthough some predictors of diffuse ISR have been reported, parameters on IVUS relating to diffuse ISR are not well characterized.MethodsWe classified 52 ISR lesions that had undergone successful stent implantation and led to restenosis into two types—focal and diffuse ISR—using quantitative coronary angiography. Restenosis was defined as ≥50% diameter stenosis, and diffuse ISR as lesion length ≥10 mm at follow-up. The remodeling index (RI) was defined as the vessel area at the target lesion divided by that of averaged reference segments.ResultsThere were no significant differences in patient, angiographic, and procedural characteristics between the focal (n = 25) and diffuse (n = 27) ISR groups. Baseline RI was significantly greater in the diffuse ISR group (1.03 ± 0.18 vs. 0.88 ± 0.24, p = 0.0159). Negative remodeling, defined as RI <0.9, was detected in 60% of the focal ISR group and in only 26% of the diffuse ISR group. By logistic regression analysis, baseline RI was the only independent predictor of diffuse ISR (p = 0.0341). Moreover, volumetric analyses revealed that lesions developing into diffuse ISR had less capacity to compensate for further plaque growth.ConclusionsAmong the first ISR lesions, baseline positive remodeling was the most powerful predictor of diffuse ISR. Measuring pre-interventional arterial remodeling patterns by IVUS may be helpful to stratify lesions at higher risk