23 research outputs found
Fluorescence spectroscopy and imaging of myocardial apoptosis
Fluorometry is used to detect intrinsic flavoprotein (FP) and nicotinamide adenine dinucleotide NADH signals in an open-chest rabbit model of myocardial ischemia-reperfusion injury. Myocyte apoptosis has been shown clinically to contribute to infarct size following reperfusion of ischemic myocardium. A noninvasive means of assessing apoptosis in this setting would aid in the treatment of subsequent ventricular remodeling. We show that in vivo fluorometry can be useful in apoptosis detection in open-chest surgeries. Specific changes in myocardial redox states have been shown to indicate the presence of apoptosis. Two main mitochondrial intrinsic fluorophores, NADH and FP signals, were measured during normoxia, ischemia, and reperfusion experimental protocol. Ischemia was induced by occlusion of the largest branch of the circumflex coronary artery and fluorescence signals are collected by applying two different fluorescence techniques: in vivo fluorometry and postmortem cryoimaging. The first technique was employed to detect FP and NADH signals in vivo and the latter technique uses freeze trapping and lowtemperature fluorescence imaging. The heart is snap frozen while still in the chest cavity to make a snapshot of the metabolic state of the tissue. After freezing, the ischemic area and its surrounding border zone were excised and the sample was embedded in a frozen buffer for cryoscanning. These two data sets, in vivo fluorometry and low temperature redox scanning, show consistent extreme oxidation of the mitochondrial redox states (higher redox ratio) suggesting the initiation of apoptosis following reperfusion. This represents the first attempt to assess myocyte apoptosis in the beating heart
Quantifying Acute Myocardial Injury Using Ratiometric Fluorometry
Early reperfusion is the best therapy for myocardial infarction (MI). Effectiveness, however, varies significantly between patients and has implications for long-term prognosis and treatment. A technique to assess the extent of myocardial salvage after reperfusion therapy would allow for high-risk patients to be identified in the early post-MI period. Mitochondrial dysfunction is associated with cell death following myocardial reperfusion and can be quantified by fluorometry. Therefore, we hypothesized that variations in the fluorescence of mitochondrial nicotinamide adenine dinucleotide (NADH) and flavoprotein (FP) can be used acutely to predict the degree of myocardial injury. Thirteen rabbits had coronary occlusion for 30 min followed by 3 h of reperfusion. To produce a spectrum of infarct sizes, six animals were infused cyclosporine A prior to ischemia. Using a specially designed fluorometric probe, NADH and FP fluorescence were measured in the ischemic area. Changes in NADH and FP fluorescence, as early as 15 min after reperfusion, correlated with postmortem assessment infarct size (r=0.695, p\u3c0.01). This correlation strengthened with time (r=0.827, p\u3c0.01 after 180 min). Clinical application of catheter-based myocardial fluorometry may provide a minimally invasive technique for assessing the early response to reperfusion therapy
Development of low-volume, high-intensity, aerobic-type interval training for elderly Japanese men: a feasibility study
BackgroundThe purposes of this study were to identify 1) the feasibility of a novel exercise protocol (elderly Japanese male version of high-intensity interval aerobic training: EJ-HIAT) and 2) its preliminary data (%V̇O2peak, rating of perceived exertion) in comparison with traditional moderate-intensity continuous aerobic training (MICT).ResultsTwenty-one sedentary elderly men, aged 60–69 years, performed two exercise protocols: EJ-HIAT, consisting of 3 sets of 2−3-min cycling at 75−85%V̇O2peak with 1−2-min active rests at 50%V̇O2peak between sets, and MICT, consisting of 40-min cycling at 65%V̇O2peak. The completion rate, defined as the rate of participants who 1) did not demand withdrawal, 2) were not interrupted by the tester, and 3) did not change the workload during either exercise protocol, of EJ-HIAT was similar to that of MICT (EJ-HIAT: 100%, MICT: 95.2%). Maximal perceived exertion ratings assessed by Borg scale were also similar between EJ-HIAT and MICT. However, objectively measured maximal intensity assessed by %V̇O2peak was higher for EJ-HIAT than for MICT (EJ-HIAT: 86.0 ± 5.6%, MICT: 67.1 ± 6.4%).ConclusionThese results suggested that EJ-HIAT has good feasibility and perceived exertion similar to MICT despite having higher objectively measured intensity than MICT. An intervention aimed as identifying the effects of EJ-HIAT on exercise tolerance should be performed in the future
Predictors of Pericardial Effusion in Patients Undergoing Pulmonary Artery Banding
Background:Although pulmonary artery banding (PAB) is a common palliative procedure for pediatric heart malformation, there are concerns of pressure overload and concomitant immune reactions in the right ventricle causing postsurgical complications such as pericardial effusion. At this time, no clear guidelines as to potential risk factors or procedural contraindications have been widely disseminated. Therefore, a study was undertaken to examine wide-ranging factors to find potential biomarkers for postsurgical pericardial effusion formation risk.Methods:A retrospective study was conducted on all cardiac surgeries performed over an eight-year period, and the main inclusion criterion was pericardial effusion development after PAB that required surgical drainage. Nine cases were then analyzed against a control group of 45 cases with respect to body measurements, concomitant surgeries, genetic screens, laboratory tests results, and cardiac function parameters.Results:Trisomy 21 was strongly associated with the development of severe pericardial effusion after PAB, and postoperative serum albumin levels in patients with trisomy 21 were associated with pericardial effusion development. Other parameters showed no significant correlation with pericardial effusion development.Conclusions:Our data indicate a strong association between trisomy 21 and pericardial effusion requiring drainage after PAB, which is in line with translational research findings. Pressure overload from PAB may play a role in the formation of severe pericardial effusion that is exacerbated by cardiac structural defects commonly associated with trisomy 21. Surgical teams should therefore use caution and plan to implement drainage in PAB cases, and postoperative serum albumin may serve as a useful biomarker for pericardial effusion formation
Congenital-idiopathic superficial femoral artery aneurysm in a 7-year-old child
Superficial femoral artery aneurysm in children is distinctly uncommon, and usually results from infection, vasculitis, connective tissue disorder, or trauma. We report a 7-year-old girl who had multiple fusiform aneurysms of the right superficial femoral artery, with no evidence of related disorders. The patient successfully underwent aneurysm resection and femoral artery reconstruction with autogenous saphenous vein. Histologic examination revealed intimal thickening with fibroplasia without severe inflammatory infiltrates or cystic medial necrosis, suggesting a congenital-idiopathic arterial aneurysm. Three years after the procedure, the saphenous vein graft is fully patent and the patient is in good condition
Development of low-volume, high-intensity, aerobic-type interval training for elderly Japanese men: a feasibility study
Development of low-volume, high-intensity, aerobic-type interval training for elderly Japanese men: a feasibility study
Abstract Background The purposes of this study were to identify 1) the feasibility of a novel exercise protocol (elderly Japanese male version of high-intensity interval aerobic training: EJ-HIAT) and 2) its preliminary data (%V̇O2peak, rating of perceived exertion) in comparison with traditional moderate-intensity continuous aerobic training (MICT). Results Twenty-one sedentary elderly men, aged 60–69 years, performed two exercise protocols: EJ-HIAT, consisting of 3 sets of 2−3-min cycling at 75−85%V̇O2peak with 1−2-min active rests at 50%V̇O2peak between sets, and MICT, consisting of 40-min cycling at 65%V̇O2peak. The completion rate, defined as the rate of participants who 1) did not demand withdrawal, 2) were not interrupted by the tester, and 3) did not change the workload during either exercise protocol, of EJ-HIAT was similar to that of MICT (EJ-HIAT: 100%, MICT: 95.2%). Maximal perceived exertion ratings assessed by Borg scale were also similar between EJ-HIAT and MICT. However, objectively measured maximal intensity assessed by %V̇O2peak was higher for EJ-HIAT than for MICT (EJ-HIAT: 86.0 ± 5.6%, MICT: 67.1 ± 6.4%). Conclusion These results suggested that EJ-HIAT has good feasibility and perceived exertion similar to MICT despite having higher objectively measured intensity than MICT. An intervention aimed as identifying the effects of EJ-HIAT on exercise tolerance should be performed in the future. Trial registration UMIN000021185 (February 26, 2016)
Colorectal carcinoma in aged patients over 75 years old : Clinicopathological study
In a review of 358 patients with colorectal carcinoma resected at the department during the past 13 years between 1978 and 1990, 41 elderly patients over 75 years old were selected (served as aged group) and compared to younger patients under 74 years old (younger group) for clinicopathological features and prognosis. Elderly patients, who represented 11.5% of all cases, were predominantly females. There was no significant difference in the localization of the tumor, depth of invasion, lymphnode metastasis and lymphatic infiltration between the two groups. No significant difference was noted in macroscopic type, but a tendency of having type 5 was observed in the elderly group. The elderly group had a significantly smaller maximum diameter of the tumor. There was a lower tendency in the positive rate of vessel invasion in the elderly group. In the stage classification and the incidence of curative resection, there were no differences between the two groups. The cumulative survical rate after resection in the elderly group was relatively lower than that in the other group