Biomedical subjects

M Osako

Publications and source records attributed to M Osako.

At least 37 records · Page 2Linked to original sources

PubMed2000

Insulin-like growth factor-I improves recovery of cardiac performance during reperfusion in isolated rat heart by a wortmannin-sensitive mechanism.

Insulin-like growth factor-I (IGF-I) has been shown to produce a short-term positive inotropic effect (PIE) in the myocardium under nonischemic conditions. IGF-I also conferred cytoprotection against ischemia and reperfusion injury in various organs. IGF-I may, therefore, facilitate the recovery of postischemic cardiac function. Isolated and crystalloid-perfused rat heart was subjected to 25 min of normothermic ischemia followed by 30 min of reperfusion. IGF-I produced PIE in a dose-dependent manner at concentrations ranging between 1 and 100 nM under nonischemic conditions. Although 1 nM isoproterenol produced much greater PIE and myocardial energy conversion efficiency (MECE) than did 65 nM IGF-I in this condition, the same concentration of IGF-I administered during reperfusion conferred better recovery of left ventricular function and MECE compared with isoproterenol. The improved cardiac performance by IGF-I was associated with lower release of creatine kinase (CK). Wortmannin (100 nM), a specific inhibitor of phosphatidylinositol kinase (PI-3 kinase), abrogated IGF-I-induced improvement of contractile function and inhibition of CK release in the postischemic heart. We conclude that IGF-I administered during reperfusion accelerates recovery of cardiac performance and mitigates myocardial injury through a wortmannin-sensitive mechanism.

Androstadienes↗

PubMed1999

Surgical treatment for a supra sinotubular junctional saccular aneurysm associated with aortic regurgitation.

We reported a patient with a saccular ascending aortic aneurysm located just above the non-coronary sinotubular junction. The aneurysm produced severe aortic regurgitation and two episodes of cardiac tamponade. By intraoperative inspection, the border between the aneurysmal wall and non-dilated portion of the normal aortic wall was distinct, and the aortic valve leaflets and aortic annulus appeared normal. Aortic valve dysfunction appeared to be caused by dilation of the noncoronary sinotubular junction and mild distortion of the noncoronary sinus because of the aneurysmal formation. We performed patch closure of the aneurysmal ostium and repaired the dilated noncoronary sinotubular junction. Postoperative echocardiography and aortography demonstrated a good coaptation of the aortic valve leaflets with trivial aortic regurgitation. Although a rupture site, dissection or carcinomatous pericarditis which is attributable to the two episodes of cardiac tamponade could not be found, pathologic examination of the aneurysm wall revealed intramural blood leakage between the mucoid degenerated media and notably thickened adventitia. In addition, there was thinning and interruption of the elastic fibers of the media. These findings are consistent with a leaking aneurysm which cause the slow development of cardiac tamponade.

Aortic Aneurysm↗

PubMed1999

Gene expression of gastric type mucin (MUC5AC) in pancreatic tumors: its relationship with the biological behavior of the tumor.

Previously it has been found that the MUC2 gene for intestinal type secretory mucin is highly expressed in intraductal papillary mucinous tumors (IPMT), which are characterized by non-invasive growth and a favorable outcome. In contrast, MUC2 mRNA is rarely expressed in invasive ductal carcinomas (IDC), which have poor outcomes. The gastric type secretory mucin, MUC5AC, is strongly expressed in the surface mucous cells of gastric mucosa. As both MUC2 and MUC5AC mucins share the characteristics of forming highly viscous gels, it is expected that not only MUC2 mucin expression but also MUC5AC mucin expression may be associated with a favorable prognosis in patients with pancreatic tumors. MUC5AC mucin gene expression was examined in 24 cases of IPMT and 38 cases of IDC by in situ hybridization using a digoxigenin-labeled oligonucleotide. The results were compared with MUC2 mucin gene expression. Neither MUC5AC mRNA nor MUC2 mRNA was detected in normal pancreatic tissues. MUC5AC mRNA was expressed in 20 of 24 cases of IPMT (83%) and in five of 38 cases of IDC (13%). In contrast, MUC2 mRNA was expressed in 14 of 24 cases of IPMT (58%) and in none of the 38 cases of IDC (0%). The expression rates of MUC5AC mRNA and MUC2 mRNA in IPMT were significantly higher than those in IDC (P< 0.001, respectively). Intraductal papillary mucinous tumors are characterized by three histological types: (i) villous dark cell type; (ii) papillary clear cell type; and (iii) compact cell type. The villous dark cell type generally expressed both MUC5AC+ and MUC2+ genes. Alternatively, the papillary clear cell type and the compact cell type usually showed MUC5AC+ and MUC2- expression. Patients with MUC5AC mRNA expression had a significantly better survival prognosis than those with no MUC5AC mRNA expression (P< 0.005). In conclusion, MUC5AC gene expression occurs in a majority of IPMT cases, even in those with no MUC2 production. MUC5AC expression can be

Adenocarcinoma, Mucinous↗

PubMed1999

[The effectiveness of glaucomatous visual field test using a size I stimulus].

PURPOSE: Perimetry using size I and III targets was conducted on glaucoma patients. The detectability of the visual field defects using a size I target and abnormal spatial summation was investigated. SUBJECTS & METHODS: Subjects were 14 eyes of 11 glaucoma patients with mild to moderate visual field defects and 11 eyes of 11 normal persons. Program 24-2 of the Humphrey Field Analyzer was applied to each subject. Based on the mean sensitivity and standard deviation at each coordinate in normal persons, the Z-score was calculated in the visual fields of glaucoma patients (absolute scotomas were excluded). RESULTS: The mean Z-score of retinal sensitivity, was less for size III than for size I in abnormal lesions, and less for size I than for size III in normal lesions (paired t-test, p < 0.01). Pathological spatial summation was found more frequently in normal lesions than in abnormal lesions. CONCLUSIONS: In mild visual field defects, size I detects abnormalities with greater sensitivity than size III. Perimetry using the size I target can be effective as a supplementary diagnostic method to detect and follow the early glaucomatous visual field.

Glaucoma↗

PubMed1999

[Home hospice care at a clinic].

For the people who want to stay at home until their last day, the primary doctor and clinic where they were diagnosed will be the most reliable supports. We have been operating a 19 bed clinic since 1996. In these three years, we have established what we call a "combination palliative care system." A team composed of two doctors, 13 nurses, 3 care aids, a social worker, and a counselor provides home care services as well as outpatient and inpatient care. From April, 1998 to March, 1999, 59 patients died of cancer. Among them, 25 patients died at home. Their primary cancers were lung (7), colon (3), pancreatic (2), breast (2), ovarian (2), brain (1), stomach (1), hepatoma (1), neck (1) and others. First of all, sufficient consultation with patients and family makes this care successful. Through this, the patient can choose his style of care. The whole staff is involved in this care in turn, so that all of us become acquainted with each patient. Home care includes: 1) medical and nursing service available 24 hours a day, 2) activation of social resources for the support of the patient user, 3) constructive cooperation with relevant institutions, 4) relieving the patient's physical and mental suffering, 5) aroma therapy, oil massage, hair cuts and music therapy, and 6) support by volunteers. In this way, as a neighborhood clinic, the combination palliative care system is valuable.

Female↗

PubMed1998

[One stage operation for aneurysm of the diverticulum of the ductus arteriosus and coronary artery bypass grafting].

Aneurysm of the diverticulum of the ductus arteriosus in the adult is rare. One stage operation for aneurysm of the diverticulum of the ductus arteriosis and coronary artery bypass grafting (CABG) is reported. A 61-year-old man was admitted for diagnosis of thoracic aneurysm on chest X-ray and CT. Chest CT scan showed an aneurysm above the left main pulmonary artery. An aortography showed the left vertebral artery originated directly from the aortic arch and a saccular aneurysm arising from the aortic isthmus and lesser curvature of the aortic arch. Coronary arteriography showed 75% stenosis at the right coronary artery (seg. #1) and 75% stenosis at the left anterior descending artery. Operation was performed through a median sternotomy. The aneurysm of 6 to 3 cm was located between the aortic isthmus and left pulmonary artery. Ascending aorta and right atrium were used to institute cardiopulmonary bypass (CPB). CABG (LITA to #7, SVG to #4 PD) was performed. Arterial cannulation was then switched to the left femoral artery. The proximal aorta was cross-clamped between the left vertebral artery and the left subclavian artery under the partial CPB, and the distal aorta was occluded with a occulusive balloon catheter via the right femoral artery. The selective left axillar artery cannulation was performed to perfuse LITA. The aneurysm was resected and closed with a patch. His post-operative course was uneventful.

Aortic Aneurysm↗

PubMed1998

MUC-1 mucin expression in invasive areas of intraductal papillary mucinous tumors of the pancreas.

The expression of MUC-1 mucin (membrane-associated mucin) and MUC-2 mucin (secretory mucin) were immunohistochemically examined in 46 invasive ductal carcinomas (IDC) and 16 intraductal papillary mucinous tumors (IPMT) of the pancreas. Intraductal papillary mucinous tumors usually reveal expansive growth. However, of the 16 IPMT examined in the present study, three showed an invasive growth pattern, which was similar to 'mucinous carcinoma', around the non-invasive growth areas. Of 46 IDC, MUC-1 mucin detected by monoclonal antibodies, DF3 and MY.1E12, was expressed in 44 cases (96%) and in 45 cases (98%), respectively, whereas MUC-2 mucin detected by polyclonal antibody, anti-MRP, was not expressed in any of the cases (0%). In contrast, in the non-invasive growth areas of the 16 IPMT, MUC-1 mucin detected by DF3 and MY.1E12 was expressed in four cases (25%) and in six cases (38%), respectively, whereas MUC-2 mucin detected by anti-MRP was expressed in 13 cases (81%). The invasive growth areas of the three IPMT showed positive expression of MUC-1 mucins detected by DF3 and MY.1E12, although the non-invasive growth areas showed negative expression of MUC-1 mucins, except for their focal positive expression in one of the three cases. These findings indicate that the invasive growth areas of IPMT acquire a characteristic of MUC-1 mucin expression that is usually seen in IDC.

Biomarkers, Tumor↗

PubMed1998

Primary pulmonary artery sarcoma.

A 66-year-old woman with a history of mitral valve replacement with a Starr-Edwards ball valve 25 years ago was treated for refractory heart failure but died of right heart failure. At autopsy, primary pulmonary artery sarcoma was found in the right ventricular outflow tract, main pulmonary trunk, and bilateral pulmonary artery, and had invaded the aortic arch. The pathohistologic diagnosis was osteosarcoma. Echocardiography, chest computed tomography and right ventriculography performed 1 year before death did not reveal the presence of a tumor in the pulmonary artery. The history of this patient shows that primary pulmonary artery sarcoma grows rapidly, with, in this case, the patient dying within 1 year of its appearance.

Aged↗

PubMed1998

Aorto-atrial fistula associated with recurrent aortic dissection after ascending aorta replacement.

A 70-year-old woman with a bicuspid aortic valve had undergone ascending aorta replacement for acute DeBakey type I dissection. Computed tomography and aortography 2 months after the operation revealed a thrombosed false lumen in the ascending aorta proximal to the prosthetic graft. However, recurrence of dissection was found at the aortic root proximal to the graft 4 years after the initial operation. Significant aortic stenosis was also noted. Despite intensive medical treatment, she had refractory and progressive heart failure. At the second surgery, an aorto-right atrial fistula, which probably was responsible for the severe heart failure was revealed. Closure of the aorto-right atrial fistula, and aortic root replacement were performed using Piehler's method, with a composite graft. The etiology and management of this rare case are discussed.

Aged↗

PubMed1997

[Effects of ischemic preconditioning on the recovery of myocardial function after unprotected ischemia and cardioplegia in the isolated and crystalloid perfused rat hearts].

Preconditioning with repetitive brief periods of ischemic (IPC) is known to induce myocardial protection against a subsequent more prolonged period of ischemia. We investigated whether IPC can offer similar beneficial effects on myocardial function after cardioplegic preservation in isolated and crystalloid-perfused rat hearts. IPC was produced by 5 periods of 1 min ischemia followed by 5 min reperfusion before 25 min of unmodified ischemia or 40 min of cardioplegia. IPC had no significant effect on the time to contractile arrest (control: 211 +/- 27 sec, IPC: 240 +/- 32 sec) after unmodified ischemia, while the time to electrical asystole was significantly (p < 0.05) shortened by IPC (676 +/- 107 sec) compared to control (1021 +/- 197 sec). However, rapid contractile arrest concomitant with electrical asystole was induced by infusion of St. Thomas' Hospital solution in control as well as in IPC-treated hearts without a significant intergroup difference (control: 33 +/- 7 sec, IPC 39 +/- 9 sec). Although myocardial ATP was significantly reduced by IPC, IPC-treated hearts showed a significantly higher ATP level after 25 min of unprotected ischemia. Accumulation of myocardial lactate after 25 min of unprotected ischemia was significantly (p < 0.05) inhibited by IPC. However, the levels of myocardial ATP and lactate after 40 min of cardioplegia were comparable between control and IPC-treated hearts. Left ventricular developed pressure (LVDP) at 30 min reperfusion after unprotected ischemia was significantly improved by IPC, while the recovery of LVDP at 30 min reperfusion after cardioplegia was comparable between control and IPC-treated hearts. The onset of ischemic contracture, i.e., a rise of left ventricular end-diastolic pressure (LVEDP), was significantly accelerated and its magnitude was significantly greater in IPC-treated hearts during unprotected ischemia and also during cardioplegia. However, a significant decrease of LVEDP during reperfusion compared to control hearts was observed only after unprotected ischemia. The amounts of creatine kinase (CK) released during 30 min reperfusion after unprotected ischemia was significantly greater in control than in IPC-treated hearts, but there was no significant difference in CK release between control and IPC-treated hearts during reperfusion after cardioplegia. These results suggest that IPC-induced cardioprotection may be induced via inhibition of anaerobic energy metabolism through a negative chronotropic effect during unprotected ischemia, but such a beneficial effect is dissipated with cardioplegia by which rapid electrical asystole is induced. It is, therefore, concluded that IPC may not provide additional myocardial protection over conventional hyperkalemic cardioplegia.

Animals↗

PubMed1997

[The relationship between statokinetic dissociation (SKD) and spatial summation--physiologic SKD in normal persons].

We investigated the relationship between physiologic statokinetic dissociation (SKD) and spatial summation in normal persons. The subjects were 13 eyes of 13 normal persons (average age : 41.9 years) with no past history of ocular disease. The kinetic program and custom program of the Humphrey Field Analyzer were followed for each subject using the targets of III 1b and III 4c to measure SKD. Spatial summation was calculated from the results of the 24 -2 program using size I, III, and V. The SKD of all normal persons for III 1b and III 4c was 18.8 +/- 3.4 and 20.1 +/- 5.4 degrees, respectively. The spatial summation for SS (III-I) and SS (V-III) was 9.8 +/- 0.7 and 4.7 +/- 0.9 (dB), respectively. Although the SKD on lower temporal meridian using the III 4c target was larger than that of the other meridian, this relation was reversed using the III 1b target. This is because the steep slope of the retina sensitivity curve in the periphery field decreases successive lateral spatial summation. Although SKD tends to be larger with the increase in age, the relationship between SKD and spatial summation was not obvious.

Adult↗

PubMed1996

[A successful surgical case of a dissecting aortic aneurysm with right-sided aortic arch and right-sided descending aorta].

The patient was a 70-year-old female whose aortogram and chest computer tomogram revealed DeBakey type IIIb dissecting aortic aneurysm in association with right-sided aortic arch, right-sided descending aorta and aberrant left subclavian artery arising from the Kommerell's diverticulum. Because she had cachexy with hoarseness and difficulty in swallowing caused by an aneurysm she received hypotensive therapy until recovery of her general condition before elective operation. The aneurysm was 7 cm in diameter and was replaced with vascular graft. Reconstruction of the aberrant left subclavian artery and closure of the false lumen via right thoracotomy were also performed under partial bypass installed between the right common femoral vein and artery using modified PCPS. Postoperative computer tomogram and aortogram showed properly replaced vascular graft and closure of false lumen. Dissecting aortic aneurysm complicated with a right-sided arch is quite rare. Including our case, 12 cases have been reported in the world and 9 cases were in Japan. This is one of the most successful surgical case for DeBakey type IIIb dissecting aortic aneurysm in association with right-sided aortic arch, right-sided descending aorta and aberrant left subclavian artery arising from the Kommerell's diverticulum.

Aged↗

PubMed1994

[The surgical treatment of coarctation of the aorta and interruption of the aortic arch in the first three months of life--effectiveness of temporary bypass between the pulmonary artery and the descending aorta].

From February 1987 to January 1994, we operated on 24 patients with coarctation of the aorta (CoA) and 9 patients with interruption of the aortic arch (IAA). A policy of staged repair was followed, consisting of reconstruction of the aortic arch with pulmonary artery banding and ligation of the ductus arteriosus in the first stage and intracardiac repair with pulmonary artery band removal in the second stage. In recent cases an extended aortic arch anastomosis was performed using a heparin-coated "shunt tube" between the pulmonary artery and the descending aorta to maintain blood flow to the lower half of the body during aortic cross-clamping. The use of the shunt increased intraoperative urine output (p < 0.05). This technique may allow patients whose condition is poor to undergo aortoplasty more safely. One patient died. This patient had CoA and total anomalous pulmonary venous return, who underwent a one-stage repair, in violation of our policy (early mortality 3.0%). There were two interim deaths before the second stage repair. At present, 18 patients have undergone staged intracardiac repair, including VSD closure (14 cases), Jatene's procedure (1), Ratelli's procedure (1), Damus-Kaye-Stansel (DKS) procedure (1), total cavo-pulmonary connection (TCPC) + DKS procedure+annuloplasty of a common atrioventricular valve (1). There were two early deaths and one late death following intracardiac repair, all in patients with IAA plus VSD.

Anastomosis, Surgical↗

PubMed1993

Immunohistochemical study of mucin carbohydrates and core proteins in human pancreatic tumors.

BACKGROUND: Pancreatic cancer has a poor prognosis, and early diagnosis of carcinoma and discrimination between malignant and benign conditions are difficult. Many pancreatic cancer-associated antigens, such as CA 19-9, DU-PAN-2, YPan-1, and SPan-1, have been studied. However, expression of Tn, sialosyl-Tn, and T antigens in tissues of different types of pancreatic neoplasms has not been investigated systematically. Moreover, little is known about the distribution of different types of apomucins in the pancreas. METHODS: The expression of Tn, sialosyl-Tn, and T antigens and DF3 (mammary type apomucin) and intestinal MRP (intestinal type apomucin) was examined immunohistochemically in 47 pancreatic tumors: 36 invasive ductal carcinomas, 5 intraductal papillary tumors, and 6 adenomas. RESULTS: In normal pancreatic tissues, neither Tn nor sialosyl-Tn antigen was expressed. In contrast, expression of both Tn and sialosyl-Tn antigens was observed in all the invasive ductal carcinomas and intraductal papillary tumors. None of the adenomas expressed both Tn and sialosyl-Tn. DF3 antigen was expressed in all invasive ductal carcinomas but not in intraductal papillary tumors, whereas intestinal MRP was expressed in all the intraductal papillary tumors but not in the invasive ductal carcinomas. CONCLUSIONS: The results from this study suggest that the expression of the mucin core protein and mucin carbohydrate antigens is correlated with the biologic behavior of pancreatic tumors. In particular, the expression of mammary type mucin core protein and intestinal type mucin core protein showed a striking contrast between invasive ductal carcinomas with a poor prognosis and intraductal papillary tumors with a favorable prognosis.

Adenoma↗

PubMed1991

[Correlation between odor thresholds and saturated vapor pressures of odorants].

The purpose of our work is to develop an estimation method for odor thresholds on the basis of physicochemical properties of odorous compounds. In this report, we examined the correlation between odor thresholds (Cth) and the saturated vapor pressures (Pvp) of various odorants. Results. 1) There were very good correlations between Pvp and k. k represents an indicator of lipid affinity. In our earlier report, k was obtained by the analysis of the gas chromatography with a column packed with a support coated by a phospholipid. Accordingly the correlations show that Pvp may be an indicator of solubility into the lipid phase. 2) It was found that correlations between Pvp and Cth were very good in several homologous series of aliphatic compounds. However ionized substances, such as acids and amines, and sulfur compounds had no good correlations. 3) In odorants having more than 3-5 carbon atoms, odor thresholds of normal types were higher than those of iso types. 4) In the series of amines, the relationship between Cth and Pvp depended upon the length and the number of alkyl chains combined with the contained nitrogen atom. 5) In the series of alcohol and aldehyde, the decrease of Cth in the rate became smaller with the decrease of Pvp.

Air Pollutants↗

PubMed1990

[Sensory scaling of odor based on mathematical studies of rating words].

Sensory scales are very important indicators for the evaluation of environmental odors, and of the effect of deodorizers. The purpose of this study is to examine reasonable methods of sensory scaling. For this purpose, the psychological values of rating words for odor intensity, odor hedonics and similarity were measured. The interval distances between categories of each scale were estimated in the method of successive categories as well. Results of this study are as follows. 1) The 6-step odor intensity scale, issued by the Environmental Agency, may be regarded as an ordinal scale, but not as an interval scale. The 9-step hedonics scale may be regarded as an interval scale. 2) Psychological values of rating words are not affected by the size and the number of category steps in the graphic scales applied to the judgements of their values. 3) The number of category steps needs to be determined based on the distribution of the psychological values. The meanings and the order of the rating words have to be clear. 4) In the construction of a numerical scale, the category values should accord nearly as possible with the psychological values of rating words. 5) In results from the method of successive categories applied to the measured values of odor intensity and similarity, interval distances between categories are unequal, and the interval distances are wide on both edges of the scale. In these cases, the values must be converted into "category values of stimuli."

Classification↗

PubMed1990

[The mean of Downs and northwestern analysis in adults].

An angle analysis and linear analysis are popularly used in clinical orthodontics. Downs analysis and Northwestern analysis are two methods of angle analysis, and the mean values reported by Iizuka in 1963 are still used. However in Japan each generation's constitution (height, weight) tends to increase year by year. For example, the mean height and weight of adult males (23 years old) have increased by 5.0cm and 7.6kg as compared with nearly 20 years ago. Therefore the mean of 20 years ago may not be appropriate. Analytical values at normal occlusion Japanese adults by Kayukawa, Iizuka, Ishikawa, Yamauchi, Miura, Iwazawa and, most recently by Asai in 1973. We obtained these values and determined the validity of currently used values.

Adult↗

PubMed1989

[Impact of odor hedonics on sensory odor intensity--physiological intensity and sensory intensity].

In this study, it is supposed that the human recognition system for odor intensity can be classified into systems of physiological intensity and sensory intensity. The former is the intensity based on the physiological response to olfaction, the latter is the intensity dependent on psychological properties such as odor qualities and odor hedonics. The purpose of this study is to make clear the relationship between physiological intensity and sensory intensity. In this paper, therefore, the quantitative relationships between all physiological intensities of odorous compounds were evaluated in experimental subjects by means of the sensory similarity test, and the impacts of the odor hedonics on the sensory intensity were examined based on the correlations between the measured sensory intensities and the hedonics of all subjects. As a result, it was confirmed that a linear relation was established between the psychological impacting factor alpha, which was the ratio of the sensory intensity to the physiological intensity, and odor hedonics. It was also estimated that methylamine had a maximum physiological intensity and ethyl isobutyrate a minimum one based on the equivalent sensory intensity.

Cognition↗