During hemodialysis (HD), blood pressure (BP) changes are frequently observed. However, the mechanism of BP changes during HD has not been fully clarified. The cardio-ankle vascular index (CAVI) ...reflects the arterial stiffness of the arterial tree from the origin of the aorta to the ankle independent from BP during measurement. Additionally, CAVI reflects functional stiffness in addition to structural stiffness. We aimed to clarify the role of CAVI in regulating the BP system during HD. We included 10 patients undergoing 4-hour HD (total 57 HD sessions). Changes in the CAVI and various hemodynamic parameters were evaluated during each session. During HD, BP decreased and CAVI significantly increased (CAVI, median interquartile range; 9.1 8.4-9.8 0 min to 9.6 9.2-10.2 240 min,
< 0.05). Changes in CAVI from 0 min to 240 min were significantly correlated with water removal rate (WRR) (r = -0.42,
= 0.002). Changes in CAVI at each measurement point were negatively correlated with ΔBP (Δsystolic BP
, r = -0.23,
< 0.0001; Δdiastolic BP
, r = -0.12,
= 0.029). Whereas one patient exhibited a simultaneous decrease in BP and CAVI during the initial 60 min of HD. Arterial stiffness monitored with CAVI generally increased during HD. CAVI elevation is associated with decreased WWR and BP. An increase in CAVI during HD may reflect the contraction of smooth muscle cells and play an important role in BP maintenance. Hence, measuring CAVI during HD may distinguish the cause of BP changes.
Myocardial injury is a problem associated with percutaneous coronary intervention (PCI). This study aimed to clarify the role of nicorandil administration in preventing myocardial injury. This study ...included patients with stable angina who underwent PCI from November 2013 to June 2016. Of 58 consecutive patients, the first 20 patients received only saline infusion after PCI (control group); the other 38 patients received a continuous intravenous infusion of nicorandil and saline after PCI (nicorandil group). Troponin I and brain natriuretic peptide (BNP) levels were measured. Vascular parameters, such as blood pressure (BP), cardiac output, cardio-ankle vascular index (CAVI), and estimated systemic vascular resistance (eSVR), were measured. Troponin I of both groups increased 12 h after PCI. Changes in BNP levels between immediately after PCI and 12 h after PCI were significantly higher in the control than in the nicorandil group (10.8 ± 44.2 vs. − 2.6 ± 14.6 pg/ml,
p
= 0.04). In the nicorandil group, BP, eSVR, and CAVI decreased significantly at 12 h after PCI compared with those immediately after PCI (
p
< 0.0001), whereas no change was observed in the control group. In a single linear analysis, the change in BP (
r
= 0.36,
p
< 0.01) and nicorandil administration (
r
= − 0.47,
p
< 0.001) was significantly correlated with the change in CAVI, multiple regression analysis revealed that the changes in CO and eSVR were significant contributing factors for the changes in CAVI. PCI could result in myocardial injury and/or cardiac burden in patients with stable angina. Nicorandil administration after PCI may be effective in relieving the burden by decreasing arterial stiffness (CAVI).
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Purpose
To determine whether a pulse waveform analysis in the optic nerve head (ONH) circulation as determined by laser speckle flowgraphy (LSFG) can provide systemic hemodynamic values — the ...systemic vascular resistance (SVR) in particular — similar to those obtained by using a Swan–Ganz catheter, which is an invasive method.
Method
Sixteen consecutive subjects were examined. Hemodynamic monitoring was obtained from right heart catheterization with a Swan–Ganz catheter and coronary angiography without an intracoronary nitroglycerin administration. Direct blood pressure was measured with a trans-radial approach. Single regression analyses were used to determine the relationship between the blowout score and blowout time, which are the items of the pulse waveform analysis in the ONH, by using LSFG and the hemodynamic parameters.
Results
The blowout time was significantly and negatively correlated with the SVR (
r
= −0.52,
p
= 0.04), the ocular perfusion pressure with the mean arterial blood pressure of the radial artery (
r
= −0.52,
p
= 0.04) and the radial artery pulse pressure (
r
= −0.52,
p
= 0.04).The pulmonary capillary wedge pressure (
r
= −0.44,
p
= 0.09) and the mean arterial blood pressure of the radial artery (
r
= −0.44,
p
= 0.09) tended to be correlated with the blowout time, but did not reach significance. The blowout score was significantly and negatively correlated with the radial artery blood pressure (
r
= −0.51,
p
= 0.046).
Conclusion
A pulse waveform analysis in the ONH by LSFG may be one of the useful methods for understanding the SVR.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Aim: The effect of nitroglycerin on proper arterial stiffness of the arterial tree has not been fully clarified. The cardio-ankle vascular index (CAVI), which is an application of the stiffness ...parameter β theory on the arterial tree from the origin of the aorta to the ankle, was developed recently. Furthermore, the stiffness of the aorta (heart-thigh β (htBeta)) and of the femoral-tibial arteries (thigh to ankle β (taBeta)) could be monitored by applying the same theory. The effects of nitroglycerin on CAVI, htBeta, and taBeta were studied comparing the values of healthy people and those of arteriosclerotic patients.Methods: The subjects were healthy people (CAVI ＜7.5, n=25) and arteriosclerotic patients (CAVI ＞9, n=25). Nitroglycerin (0.3 mg) was administrated sublingually, and various arterial stiffness indices were measured at one-minute intervals for a period of 20 minutes using Vasera VS-1500 (Fukuda Denshi, Tokyo).Results: After the administration of nitroglycerin in healthy people, CAVI decreased significantly after 5 min. from 6.76(6.32-7.27) to 5.50(4.70-6.21), P＜0.05, and recovered after 15 min. htBeta from 5.10(4.76-5.76) to 3.96(3.35-4.79), P＜0.05, and taBeta from 14.41(10.80-16.33) to 10.72 (9.19-13.01), P＜0.05 also decreased significantly. In arteriosclerotic patients, CAVI decreased after 5 min. from 10.47(9.67-11.29) to 9.71(8.74-10.57), P＜0.05 and recovered after 15 min. htBeta did not significantly change from 12.00(11.46-13.21) to 11.81(10.14-13.83), ns, but taBeta decreased significantly from 18.55(12.93-23.42) to 12.37(9.68-16.99), P＜0.05.Conclusion: These results indicate that a nitroglycerin-induced decrease of arterial stiffness is more prominent in muscular arteries than in elastic arteries, and this effect was preserved much more prominently in arteriosclerotic patients than in healthy people.
Purpose: To evaluate whether the features of sleep-disordered breathing (SDB) are stronger independent factors for proliferative diabetic retinopathy (PDR) compared to the incidence of metabolic ...syndrome (MetS) and the number of its individual components.
Methods: We studied a cross-sectional total of 132 patients with type 2 diabetes. Thirty-nine patients had non-proliferative diabetic retinopathy (NPDR) and 93 patients had PDR. Pulse oximetry was conducted, and the patients' mean oxygen saturation (mean SpO2%) and 4% oxygen desaturation index (4% ODI times/hour) were evaluated. We compared the SDB and MetS variables between the NPDR and PDR patients. A logistic regression analysis was used to determine the independent factors for the diagnosis of PDR.
Results: The MetS diagnosis was made significantly more often in the PDR group (p = 0.04). The number of individual MetS components was significantly greater in the PDR group compared to the NPDR group (p = 0.01). The mean SpO2 of the NPDR group was not significantly different from that of the PDR group. The 4% ODI in the NPDR group was significantly lower than that in the PDR group (p = 0.01). The logistic regression analysis using the prevalence of MetS and the number of MetS components revealed that younger age and high 4%ODI value were independent factors contributing to the diagnosis of PDR.
Conclusion: Our findings confirmed that compared to MetS and the number of its individual components, SDB may be a factor contributing to the progression to PDR. However, further careful longitudinal validation studies are needed.
Purpose
To evaluate the relationship between the parameters of pulse waveform analysis in the optic nerve head using laser speckle flowgraphy (LSFG) and intima-media thickness (IMT) and severity of ...carotid arterial plaque.
Design
Prospective and cross-sectional study.
Methods
One hundred seventy-six subjects were studied. Mean IMT and plaque score obtained from high-resolution B-mode ultrasound were evaluated. If mean IMT was 1 mm or greater, abnormal carotid artery thickening was diagnosed; if the plaque score exceeded 10, severe atherosclerosis was diagnosed. Blowout time and blowout score, which are parameters of pulse waveform analysis using LSFG, were evaluated. Logistic regression analyses determined the independent factors for abnormal carotid artery thickening and severe atherosclerosis. The cutoff levels for abnormal carotid artery thickening and severe atherosclerosis were analyzed using a conventional receiver operating characteristic (ROC) curve.
Results
Logistic regression analysis showed that blowout time and body mass index contributed independently to abnormal carotid artery thickening, and blowout score contributed independently to severe atherosclerosis. The ROC curve showed that sensitivity and specificity of the blowout time and blowout score were equivalent to or greater than those of other factors. The cutoff level of the blowout time for abnormal carotid artery thickening was 46.4; the cutoff level of the blowout score for severe atherosclerosis was 71.8.
Conclusions
Measurement of blowout time and blowout score in the optic nerve head by LSFG can be useful for evaluating mean IMT and plaque score, which are parameters of carotid atherosclerosis.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
To evaluate the relationships between parameters of the pulsatile flow form in the optic nerve head shown by laser speckle flowgraphy (LSFG) and the left ventricular (LV) end-diastolic pressure and ...mass obtained by echocardiography. We cross sectional analyzed the cases of 175 subjects who had undergone polysomnography. Standard M-mode two-dimensional color Doppler imaging was performed to evaluate the E/e′ ratio (which represents the LV end-diastolic pressure) and LV mass. The pulsatile flow form analysis parameters of the blowout score and acceleration time index were evaluated. The parameters were analyzed separately for the tissue, vessels and throughout the optic nerve head (All). We performed a single regression analysis and a multiple regression analysis to determine whether pulsatile flow form are independent factors for the E/e′ ratio and LV mass. The factors contributing independently to the E/e′ ratio were blowout time-Tissue (standard regression = − 0.27,
t
-value = − 2.90,
p
< 0.0001) and body mass index (BMI) (0.16, 2.05,
p
= 0.04). The factors that were shown to independently contribute to the LV mass were urinary albumin concentration (0.30, − 2.90,
p
< 0.0001), BMI (0.28, 4.09,
p
< 0.0001), differences of gender (men = 1, women = 0: 0.23, 3.28,
p
= 0.001), acceleration time index-Vessel (− 0.23, − 2.99,
p
= 0.003) and mean arterial blood pressure (0.17, 2.61,
p
= 0.01). Our results confirmed that parameters of the pulsatile flow form of ocular microcirculation obtained by LSFG are significantly correlated with the LV end-diastolic pressure ratio and LV mass.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The modulation of a switching field by a spin-transfer torque generated by the spin-pumping effect is demonstrated in spin-valve strips. A spin current pumped into a spin valve prefers an ...antiparallel configuration of magnetization, so that the hysteresis loop of a soft magnetic layer is shifted by applying an alternating-current magnetic field with a frequency that matched the resonant condition of a hard magnetic layer. Furthermore, we confirmed that an alternating spin current generated by the spin pumping in the hard magnetic layer produces an orthogonal magnetic torque that can reduce the coercive field of the soft magnetic layer.
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•Multilayer thin films were prepared on the surface of MPs to load DPBA.•H2O2 induced DPBA release from the MPs due to oxidative reaction.•Glucose oxidase-modified MPs released DPBA ...in response to 0.1mM glucose.
Polymer-coated magnetic particles (MPs) were prepared to study the binding of fluorescence dye on the surface and its H2O2-induced release. For this goal, multilayer films were prepared by layer-by-layer deposition of shikimic acid-appended poly(allylamine hydrochloride) (SA-PAH) and poly(styrenesulfonate) (PSS) on the surface of MPs. 3-(Dansylamino)phenylboronic acid (DPBA) was loaded on the MPs through boronate ester bonding between SA-PAH and DPBA. DPBA was released from the MPs in response to H2O2 as a result of breakage of the boronate ester bond by an oxidative reaction with H2O2. DPBA release was dependent on the H2O2 concentration. For example, 65% and 93% of the DPBA was released from (SA-PAH/PSS)4SA-PAH film-coated MPs in 30min after the addition of 0.1 and 0.5mM H2O2, respectively. In addition, the multilayer film-coated MPs were further modified by using glucose oxidase (GOx) to develop glucose-induced release systems. GOx-modified MPs released DPBA in response to 0.1mM d-glucose as a result of H2O2 generation through a GOx-catalyzed oxidation reaction of d-glucose. The results suggest a potential use of the multilayer film-coated MPs in the development of H2O2- and/or glucose-sensitive drug delivery systems.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Aim: To determine whether there is a significant correlation between optic nerve head circulation determined by pulse wave analysis of laser speckle flowgraphy (LSFG), and the cardio-ankle vascular ...index (CAVI), left ventricular (LV) function, and age. Methods: Forty-nine men who visited the Vascular Function Section of Toho University Sakura Medical Center, Chiba, Japan were studied. The mean age of the subjects was 60.7±10.6 years (range 29 to 80 years). The CAVI, left ventricular ejection fraction (LVEF) as a function of the systolic LV function, early diastolic mitral annulus velocity (e'), and the ratio of transmitral early peak velocity (E) to e' (E/e' ratio) as the diastolic LV function, and the optic nerve head circulation determined by pulse wave analysis of the LSFG. This parameter was named the blowout time (BOT). Results: The BOT was significantly correlated with age, heart rate, body mass index (BMI), triglyceride, LVEF, e' velocity, E/e' ratio, and CAVI. The results of multiple regression analysis showed that age was significantly associated with CAVI (r= 0.36, p=0.002), BOT (r=−0.30, p=0.01) and e' velocity (r=−0.21, p=0.04). Conclusions: The BOT of the optic nerve head circulation determined by LSFG was significantly correlated with age but was independent of cardiac diastolic function and arterial stiffness. This suggests that the damage to different organs increases with age. Our results confirmed that BOT can be helpful in evaluating physiological aging of the microcirculation.
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