PubMed Health⌕ Search

Biomedical subjects

Minoru Ono

Publications and source records attributed to Minoru Ono.

At least 19 recordsLinked to original sources

The beneficial effect of coronary-artery-bypass surgery on survival in patients with diabetic retinopathy.

OBJECTIVE: The presence of retinopathy is a predictor of mortality following coronary revascularization in diabetics. We studied whether revascularization by coronary-artery-bypass surgery (CABG), as compared with percutaneous coronary intervention (PCI), influences the prognosis in diabetics with retinopathy. METHODS: Between April 1996 and March 2004, 1489 patients underwent revascularization as an initial procedure. Among these a total of 319 diabetics underwent retinal examination prior to the initial revascularization. These patients were classified according to whether they had retinopathy and whether they had undergone CABG, either initially or after PCI. Mortality rates were estimated from the time of initial revascularization procedure. RESULTS: The average follow-up from the time of initial revascularization was 48.2+/-28.6 months. In 153 diabetics with retinopathy, 59 eventually underwent CABG. During the entire follow-up period, there were 2 (3.4%) deaths in diabetics with retinopathy who underwent CABG and 14 (14.9%) deaths in those who did not have CABG. Mortality curves differed significantly between the two groups (P = 0.007). After adjustment for risk factors, the relative risk of death was 0.13 afforded by CABG (95% CI, 0.03-0.62; P = 0.011). In 166 diabetics without retinopathy, mortality curves were similar between the patients who underwent CABG and those who did not have CABG (P = 0.94). CONCLUSIONS: CABG conferred a survival advantage in diabetics with retinopathy. In contrast, no survival advantage was evident in diabetics without retinopathy undergoing CABG. Retinal status should be taken into consideration when considering revascularization strategy for diabetics who have coronary artery disease.

Aged↗

Cryopreservation does not alter the allogenicity and development of vasculopathy in post-transplant rat aortas.

BACKGROUND: Cryopreservation is a valuable technique for storing heart valve and vascular allografts. However, the biological ramifications of cryopreservation are still unclear; therefore, using animal experiments we assessed how 'cryopreservation' influences graft allogenicity and cell viability. METHODS: Thoracic aortas of Lewis rats were prepared as fresh (F) or cryopreserved (CP) grafts, and implanted into the infrarenal aorta of Lewis or Brown Norway rats (BNs). The grafts and spleens were harvested at post-operative day 7 and 28 (POD7, POD28) for analyses. RESULTS: First, the systemic immune response to transplantation was estimated by mixed lymphocyte reaction analyses using spleen cells from naïve or recipient BNs. The alloreactivity of the recipients increased to 1.5 times that of the naïve BNs at POD7 and POD28, when stimulated by mitomycin C-treated Lewis spleen cells. Second, local immune response was estimated by TNFalpha, IFNgamma, and iNOS mRNA expression in the grafts by quantitative PCR, which revealed 20- to 40-fold increases at POD28 after allotransplantation. Third, endothelial cell viability was estimated by endothelial NOS mRNA expression level: it was similar and highest in F and CP grafts before transplantation then significantly decreased after both syngeneic and allogeneic transplantation. Finally, intimal hyperplasia, expressed by I/M ratio, developed over time after allotransplantation, reaching 2.5 times the thickness of F grafts before transplantation. The results of these experiments revealed no difference between F and CP grafts before and after transplantation. CONCLUSION: Cryopreservation did not modify the allogenicity of vascular allografts and had minimal adverse impacts on graft cell viability.

Animals↗

Impact of diabetic retinopathy on cardiac outcome after coronary artery bypass graft surgery: prospective observational study.

BACKGROUND: Diabetic retinopathy is a manifestation of more severe diabetes. We sought to assess the impact of diabetic retinopathy on cardiac outcome of coronary artery bypass graft surgery (CABG). METHODS: We prospectively assessed the status of the retina of 74 consecutive diabetics who were referred for first-time CABG, and compared cardiac outcome of CABG in diabetics with retinopathy with that in those without retinopathy. Cardiac events included recurrent angina or congestive heart failure that needed admission to hospital, myocardial infarction, repeat revascularization, and cardiac death. RESULTS: Twenty-six diabetics had retinopathy and 48 diabetics did not have retinopathy. Diabetics with retinopathy were likely to have higher hemoglobin A1c level (p = 0.048), and receive insulin treatment (p = 0.0065). In the 12 months of follow-up, 13 cardiac events occurred in diabetics with retinopathy and 7 in those without retinopathy (p = 0.0021). Among diabetics with retinopathy, heart failure or death due to heart failure accounted for 54% (7 of 13) of these cardiac events. Kaplan-Meier analysis showed significant difference in cardiac event-free survival between the two groups (p < 0.001). After adjustment for differences in patients' characteristics, diabetic retinopathy remained a predictor of cardiac event (adjusted relative risk = 4.2, 95% confidence interval, 1.5% to 11.9%; p = 0.0067). CONCLUSIONS: After CABG, diabetics with retinopathy have a substantially increased risk of cardiac events, especially of congestive heart failure.

Angina Pectoris↗

Erythropoietin protects the central nervous system during prolonged hypothermic circulatory arrest: an experimental study in a canine model.

OBJECTIVE: Current data suggest that erythropoietin protects the brain and the spinal cord from ischemic and traumatic injury. In this study, we determined whether erythropoietin protects the central nervous system during prolonged hypothermic circulatory arrest in an experimental canine model. METHODS: Ten adult beagle dogs were randomly and intravenously injected with either 5000 U/kg recombinant human erythropoietin or normal saline. Each dog was then subjected to a cardiopulmonary bypass and 120 minutes of deep hypothermic circulatory arrest (18 degrees C). The level of tau proteins in the cerebrospinal fluid, a modified marker of neurologic deficit in dogs, and the histopathologic characteristics of the brains and spinal cords were then examined. RESULTS: The level of tau proteins was significantly lower in the erythropoietin-treated group than in the untreated group at 6 hours (20 +/- 12 vs 144 +/- 54 pg/mL; P = .036) and 12 hours (64 +/- 35 vs 478 +/- 103 pg/mL; P = .01) after the operation. The total Neurologic Deficit Score was 59 +/- 31 (0, normal; 500, brain death) in the erythropoietin-treated group, compared with 376 +/- 30 in the untreated group (P = .0117). Histopathologic examination revealed that ischemic neuronal changes and apoptosis in the hippocampus CA1 were significantly lower in the erythropoietin-treated group (P < .01 and P = .028, respectively). CONCLUSIONS: This study showed that erythropoietin protected the central nervous system during prolonged hypothermic circulatory arrest, partly by preventing both necrosis (ischemic neuronal changes) and apoptosis.

Animals↗

Intermittent pressure augmentation during retrograde cerebral perfusion under moderate hypothermia provides adequate neuroprotection: an experimental study.

OBJECTIVE: For cerebral protection during aortic surgery, we introduced a novel retrograde cerebral perfusion method with intermittent pressure augmentation. We then assessed whether this novel method provides benefits similar to those provided by antegrade selective cerebral perfusion. METHODS: Eighteen dogs were randomly divided into 3 groups: the RCP-INT group, intermittent-retrograde cerebral perfusion at 15 mm Hg with intermittent pressure augmentation to 45 mm Hg (n = 6); the ASCP group, antegrade selective cerebral perfusion at a flow rate of 10 mL x kg(-1) x min(-1) (n = 6); and the sham group, no circulatory arrest (n = 6). Cooling (26 degrees C) with cardiopulmonary bypass and 60 minutes of circulatory arrest were performed in the RCP-INT and ASCP groups. The levels of tau protein in the cerebrospinal fluid and the diameters of the retinal vessels were measured. The neurologic deficit scores and the histopathologic damage scores of the brains were determined. RESULTS: The total postoperative tau protein levels (calculated as the area under the curve) did not differ significantly between the RCP-INT and ASCP groups (203 +/- 87 pg x mL(-1) x h vs 154 +/- 69 pg x mL(-1) x h, P = .95). The retinal vessels were effectively dilated at an augmented pressure of 45 mm Hg in the RCP-INT group. The total neurologic deficit score (0 = normal, 500 = brain death) and histopathologic damage score (0 = normal, 40 = worst) were not significantly different between the RCP-INT and ASCP groups (neurologic deficit score: 75 +/- 21 vs 70 +/- 21, P = .98; histopathologic damage score: 13.5 +/- 1.5 vs 14.2 +/- 1.3, P = .84). CONCLUSIONS: Intermittent augmented pressure dilated the cerebral vessels, allowing adequate blood supply without injuring the brain. This retrograde cerebral perfusion method provides adequate neuroprotection during moderate hypothermia.

Animals↗

Retrograde cerebral perfusion with intermittent pressure augmentation provides adequate neuroprotection: diffusion- and perfusion-weighted magnetic resonance imaging study in an experimental canine model.

OBJECTIVE: Diffusion- and perfusion-weighted magnetic resonance imaging can identify ischemic brain injury in the hyperacute stage. For neuroprotection during thoracic aortic surgery, we developed a novel retrograde cerebral perfusion with intermittent pressure augmentation. The purpose of this study was to assess the efficiency of this novel method for neuroprotection in real time by using diffusion- and perfusion-weighted magnetic resonance imaging. METHODS: Sixteen beagle dogs were randomly divided into 4 groups: the antegrade selective cerebral perfusion group (n = 4; antegrade selective cerebral perfusion at a flow rate of 10 mL x kg(-1) x min(-1)); the intermittent retrograde cerebral perfusion group (n = 4; retrograde cerebral perfusion at a baseline pressure of 15 mm Hg with intermittent pressure augmentation to 45 mm Hg every 30 seconds); the conventional retrograde cerebral perfusion group (n = 4; conventional retrograde cerebral perfusion at a fixed pressure of 25 mm Hg); and the circulatory arrest group (n = 4; only circulatory arrest). Diffusion- and perfusion-weighted magnetic resonance images were acquired during each session of cerebral perfusion. Regions of interest were defined, and the apparent diffusion coefficient and relative regional cerebral blood volume were calculated in these regions of interest. Finally, the brain was evaluated for its histopathologic damage score. RESULTS: The best apparent diffusion coefficient values were observed in the intermittent retrograde cerebral perfusion group in all the regions of interest, although the relative regional cerebral blood volume values were mostly lower than those in the antegrade selective cerebral perfusion group. The total Histopathologic Damage Score (0, normal; 32, worst) in the intermittent retrograde cerebral perfusion group (8.0 +/- 0.6) was significantly lower than that in the conventional retrograde cerebral perfusion (17.5 +/- 1.7; P < .01) and circulatory arrest (25 +/- 1.0; P < 0.01) groups and was equivalent to that in the antegrade selective cerebral perfusion group (7.8 +/- 0.8; P = .9). CONCLUSION: Intermittent retrograde cerebral perfusion provides adequate neuroprotection by allowing high apparent diffusion coefficient values to be maintained.

Animals↗

Double mapping with subareolar blue dye and peritumoral green dye injections decreases the false-negative rate of dye-only sentinel node biopsy for early breast cancer: 2-site injection is more accurate than 1-site injection.

BACKGROUND: The optimum sentinel node biopsy (SNB) mapping method for breast cancer remains to be determined. No matter which mapping agents are used, 2-site injection may be superior to 1-site injection in limiting the false-negative rate. METHODS: We examined whether a double-mapping method with subareolar injection of blue dye and peritumoral injection of green dye would decrease the false-negative rate of dye-only SNB in 145 patients with early breast cancer. RESULTS: The identification rate for blue-dyed and/or green-dyed (including mixed color-dyed) lymph nodes was 96.6% (140/145). Sensitivity and specificity were 95.1% (39/41) and 100% (99 of 99), respectively. Accuracy was 98.6% (138/140) with a false-negative rate of 4.9% (2/41). There were 4 patients in whom nodes of each color were found, but nodes of only 1 color were shown to be positive. The primary tumors of these 4 patients and of the 2 patients with false-negative results were located in the upper-outer quadrant of the breast. When only blue-dyed or green-dyed nodes (including mixed color-dyed nodes) were counted, the false-negative rates were 10.3% (4/39) for the subareolar mapping technique and 10.0% (4/40) for the peritumoral mapping technique. CONCLUSIONS: The double-mapping method based on subareolar and peritumoral injections decreases the false-negative rate of dye-only SNB for early breast cancer. Variations in lymphatic channels may exist in the lateral half of the breast and thus may influence identification of positive sentinel nodes. This finding should be taken into account in cases of multicentric breast cancer.

Adult↗

A surgical case of symptomatic coronary artery-pulmonary artery fistula.

We describe a 55-year-old female patient with multiple plexiform coronary artery-pulmonary artery fistulas, who presented with ischemic episodes accompanying an inversion of T wave on an electrocardiogram even though it was a small shunt size. The surgical procedure involved closure of the openings of the fistulas from inside the pulmonary trunk using cardiopulmonary bypass with additional ligations. Postoperative coronary angiogram revealed complete interruption of the coronary artery-pulmonary trunk fistulas resulting in complete resolution of the patient's chest symptoms.

Angina Pectoris↗

Isoechoic axillary lymph node metastases of mucinous carcinoma of the breast: a case report.

We report a case of isoechoic axillary lymph node metastasis of mucinous carcinoma (so-called pure mucinous carcinoma) of the breast. A 47-year-old premenopausal woman was referred to our hospital with a 2 years history of mass and distortion of her left breast and with recent worsening of her symptoms. Ultrasonography demonstrated a well-circumscribed mass, about 5 cm in diameter, which was isoechoic compared to the surrounding fat tissue. Distal enhancement was also recognized. A left axillary ultrasonographic scan demonstrated four nodules, which were indistinct because of their isoechogenicity compared to the surrounding tissue. Based on a preoperative diagnosis of mucinous carcinoma of the left breast with left axillary lymph nodes metastases, left mastectomy and left axillary nodal dissection were performed. Mucinous carcinoma with axillary lymph node metastases was diagnosed histologically. The lymph node metastases showed histological findings identical to those of the primary tumor, which was considered to be the reason for their isoechogenicity. Although lymph node metastasis of mucinous carcinoma of the breast is rare, ultrasonographers should perform careful scanning when the primary breast mass is suspicious for mucinous carcinoma, because lymph node metastases of mucinous carcinoma can be more indistinct and difficult to detect than those of other types of breast cancer.

Adenocarcinoma, Mucinous↗

Human umbilical cord blood cells improve cardiac function after myocardial infarction.

Human umbilical cord blood (UCB) contains an abundance of immature stem/progenitor cells and has been clinically used as an alternative to bone marrow transplantation. In addition, cord blood can be obtained non-invasively, in contrast to invasive bone marrow aspiration. We investigated the potential of human UCB CD34(+) cells to improve cardiac function following myocardial infarction. Myocardial infarction was induced in Wistar rats by ligation of the left coronary artery. Either 2x10(5) human UCB CD34(+) cells or equivalent cell-free medium was injected into the injured myocardium of the rats following induction of myocardial infarction. CD34(+) cell transplantation significantly improved ventricular function as compared to the control group. Immunofluorescence staining for human CD34, CD45, and PECAM-1 revealed surviving cells in the myocardium. Our findings suggest that transplanted human cells survived and improved cardiac function following myocardial infarction. These results may show the usefulness of UCB CD34(+) cells for myocardial infarction.

Animals↗

Management of infected grafts and aneurysms of the aorta.

Seventeen patients treated for infected grafts (11/17) or aneurysms (6/17) of the aorta between 1998 and 2003 were reviewed to evaluate our experience with aortic infection. The causative organisms were identified in 12 patients (71%), with 5 (29%) having methicillin-resistant Staphylococcus aureus. A periaortic abscess occurred in eight patients, and all of them were associated with infected grafts. Surgical treatment included cryopreserved allograft replacement in eight patients, prosthetic graft replacement in four patients, and drainage with or without omental wrapping in five patients. One patient was still hospitalized at the end of the study period. Five patients with infected grafts died after the operation during the initial hospitalization. No early mortality occurred in the aneurysm group. The early mortality rate was 31% for all patients, 50% for the graft group, and 63% for patients with a periaortie abscess. Another patient with an infected aneurysm died of arrhythmia after discharge from the initial hospitalization, Ten patients are still alive without evidence of reinfection. The early mortality rate for patients with infected aortic grafts is higher than that for those with infected aneurysms, especially when a periaortic abscess accompanies them. However, the late outcome is favorable, with no reinfection or late treatment-related deaths.

Abscess↗

A novel protocol of retrograde cerebral perfusion with intermittent pressure augmentation for brain protection.

OBJECTIVES: We examined a novel protocol of retrograde cerebral perfusion with intermittent pressure augmentation to improve the clinical usefulness of this procedure, in a canine model, because a high retrograde cerebral perfusion pressure may be required to open cerebral vessels. METHODS: Eighteen dogs (25.2 +/- 4.1 kg) were randomly divided into the following 3 groups: circulatory arrest group (circulatory arrest alone), conventional-retrograde cerebral perfusion group (conventional retrograde cerebral perfusion at 25 mm Hg), and intermittent-retrograde cerebral perfusion group (retrograde cerebral perfusion at 15 mm Hg with intermittent pressure augmentation to 45 mm Hg). The animals were cooled down to 26 degrees C under cardiopulmonary bypass and underwent 60 minutes of circulatory arrest with or without retrograde cerebral perfusion in accordance with the protocol described. They were weaned from cardiopulmonary bypass after rewarming and observed for 12 hours after the procedures. The retinal vessels were observed as a means of noninvasive direct visualization of the cerebral vascular system. The level of Tau proteins in the cerebrospinal fluid was measured as a marker of neuronal damage. RESULTS: While the retinal vessels were fully distended with blood (100%) at a retrograde cerebral perfusion pressure of 45 mm Hg in the intermittent-retrograde cerebral perfusion group, full distension of the retinal vessels was not observed in the conventional-retrograde cerebral perfusion group (67%). The level of Tau proteins, measured 12 hours after the operation, was lower in the intermittent-retrograde cerebral perfusion group (247 +/- 70 pg/mL) than in the circulatory arrest group (1313 +/- 463 pg/mL; P < .05) or the conventional-retrograde cerebral perfusion group (1449 +/- 693 pg/mL; P < .05). Histopathologic examination revealed that the most effective brain protection was obtained in the intermittent-retrograde cerebral perfusion group (P < .05). CONCLUSIONS: Intermittent-retrograde cerebral perfusion effectively opens up cerebral vessels to allow adequate blood supply to the brain, thereby minimizing brain damage. This novel method may protect the cerebral system effectively from ischemia during circulatory arrest.

Animals↗

Is the guideline the cause of structural failure in current polyester vascular prostheses? An experimental study.

To evaluate the impact of the guideline on the structural failure of current polyester vascular prostheses, we studied seven unsealed polyester vascular prostheses. An accelerated time test was used for assessing degradation of polymeric medical materials at pH 7.4 in phosphate buffer at a temperature of 95 degrees C. Probe burst strength was determined on the guideline and on standard parts of the prostheses during the accelerated time test. Weight-average molecular weights of the guideline and of the standard parts in all knitted grafts during the accelerated time test were measured. The guideline was significantly weaker than the standard parts in most prostheses. The guideline had significantly lower values of weight-average molecular weights than the standard parts in most knitted grafts. This study showed that guideline degeneration was one factor responsible for the structural failure of some current polyester vascular prostheses.

Blood Vessel Prosthesis↗

[A case of recurrent breast cancer successfully treated with capecitabine monotherapy].

A 51-year-old woman underwent pectoralis-preserving mastectomy for right breast cancer (squamous cell cancer, f, T1c, ly0, v0, N2 (18/33), p53 (3+), HER2 (2+), ER (-), PgR (-), T1cN2M0 (Stage IIIA) in March 2001, and received systemic chemotherapy using doxorubicin combined with cyclophosphamide, followed by paclitaxel. After chemotherapy, radiotherapy was added to the chest wall, supraclavicular and parasternal regions. In March 2002 (disease-free interval of one year), liver metastasis was revealed. Systemic therapy using docetaxel, and hepatic artery infusion therapy with epirubicin following docetaxel, failed. Since June 2003, capecitabine monotherapy (2,400 mg/day) was initiated for the liver and lymph node metastases in the mediastinum and retroperitoneum. After 3 cycles, all metastases responded and a marked response has been maintained for 15 months. This therapy is being continued (18 cycles), and no serious side effects have been encountered. Capecitabine monotherapy is safe and very useful for recurrent breast cancer.

Antimetabolites, Antineoplastic↗

Breast cancer in Japanese men: does sex affect prognosis?

BACKGROUND: Breast cancer has received much less investigative attention in Asian men than in Caucasian men. We examined whether the prognosis of Japanese men with breast cancer differs from that of Japanese women with the disease. METHODS: The clinicopathological features of 14 Japanese men with breast cancer were reviewed and age- and stage-matched case-control analysis of these men and 140 female patients was performed. RESULTS: Disease-free survival (p=0.94) and overall survival (p=0.62) did not differ significantly between the sexes. Five-year disease-free survival was 77% for the men and 75% for the women, and the 5-year overall survival was 92% for the men and 86% for the women. The disease recurred in 2 men but none died of breast cancer, although 3 died of other causes during the median follow-up period of 7 years. There were no significant differences in p53 mutation (p=0.20) or erbB-2 oncoprotein overexpression (p=0.33) between the men and women studied. CONCLUSION: Survival rates of Japanese male and female breast cancer patients are similar when age and stage of the disease are taken into consideration. However, comorbid disease mortality is likely the major contributor to clinical outcome in Japanese male breast cancer.

Aged↗

KB-R9032, newly developed Na(+)/H(+) exchange inhibitor, attenuates reperfusion-induced arrhythmias in isolated perfused rat heart.

PURPOSE: This study was conducted to elucidate the effects of KB-R9032, a newly developed Na(+)-H(+) exchange inhibitor, on reperfusion-induced ventricular arrhythmia in the isolated perfused rat heart. METHODS: Male Wistar rat hearts ( n = 48; 12 for each group) were perfused with modified Krebs-Ringer's solution equilibrated with 5% carbon dioxide in oxygen by means of the Langendorff technique. An occluder was placed around the left anterior descending coronary artery (LAD). Heart rate, coronary flow, and ECG were monitored. Drug-free perfusate was used for 10 min before switching to a perfusate containing various concentrations of KB-R9032. The added concentrations of KB-R9032 varied in the range of 0 (control) to 1 x 10(-5) mol x l(-1). Each heart was subjected to regional ischemia (occlusion of LAD for 11 min) and to 3 min of reperfusion (release of the ligation). RESULTS: In the control group, reperfusion-induced ventricular fibrillation (VF) occurred in 91.7%, and the duration was 158.2 +/- 14.4 s (mean +/- SEM); however, 1 x 10(-7), 1 x 10(-6), and 1 x 10(-5) mol x l(-1) KB-R9032 reduced the incidence of VF to 75.0%, 42.9%, and 6.7%, respectively ( P < 0.05 at 1 x 10(-5) mol x l(-1) of KB-R9032) and reduced the duration of VF to 64.8 +/- 22.1, 16.8 +/- 10.1, and 1.2 +/- 1.2 s, respectively ( P < 0.05 at 1 x 10(-6) and 1 x 10(-5) mol x l(-1) of KB-R9032). CONCLUSION: It was shown in this study that the Na(+)/H(+) exchange inhibitor KB-R9032 suppresses reperfusion arrhythmias in the ischemia-reperfusion model of isolated rat heart.

Animals↗