Search PubMed⌕ Search

Biomedical subjects

K Dohi

Publications and source records attributed to K Dohi.

At least 235 records · Page 13Linked to original sources
PubMed1997

Near-infrared spectroscopic method for assessing the tissue oxygenation state of living lung.

To quantify changes in tissue oxygenation of pathologic lungs, we applied a novel method using near-infrared spectroscopy (NIRs). In in vitro experiments, we assayed the effect of photon scattering on the absorption spectra of an in vitro system simulating structures of lung, which consists of test tube containing air in hematocrit tubes and red blood cell suspension with various predetermined hemoglobin concentrations. It was determined that photon scattering of the tissue containing air did not affect the absorption in the NIR region. In in vivo experiments, we tested the applicability of the NIRs technique in rat lungs under the following conditions: (1) hypoxic loading; (2) administration of an inhibitor (NaCN) of the mitochondrial respiratory chain; (3) hemorrhagic shock. We found that: (1) Changes in hemoglobin oxygenation state in the lung measured by NIRs depended on inspired oxygen concentrations; (2) NaCN-induced reduction of cytochrome oxidase a,a3 in the lung was observed; and (3) Total hemoglobin levels in the lung decreased after bleeding. Changes in the hemoglobin oxygenation state and cytochrome oxidase redox state in the lung were determined using the least-square-curve fitting for NIR absorption spectra. Our NIRs technique was capable of assessing the hemoglobin oxygenation and cytochrome oxidase redox state in the lung.

Animals↗
PubMed1997

Absence of myocardial 123I-BMIPP uptake in the presence of a normal coronary angiogram and normokinetics on a left ventriculogram.

We present the case of a 44-year-old man with abnormal myocardial fatty acid metabolism who exhibited no myocardial uptake of 123I-beta-methyl- iodophenyl pentadecanoic acid (123I-BMIPP). This patient presented to our hospital with an ECG abnormality detected during a medical check-up. He felt no chest discomfort, but a 12-lead ECG at rest showed flat T-waves in leads I, V5, and V6 with no marked ischemic changes during exercise. A left ventriculogram and coronary angiograms were normal. Thallium-201 single photon emission computed tomography imaging revealed a normal myocardial uptake, but 123I-BMIPP imaging showed no such uptake. However, 18F-labelled fluorodeoxyglucose positron emission tomography imaging after an overnight fast showed a marked increase in myocardial uptake. It appears that myocardial uptake of 123I-BMIPP was totally lacking and that energy production by the myocardium during fasting depended on the metabolism of glucose rather than of fatty acids.

Adult↗
PubMed1997

A case of dilated cardiomyopathy with abnormal atrioventricular conduction 5 years before the appearance of left ventricular systolic dysfunction.

The first manifestation of dilated cardiomyopathy is usually dyspnea as a result of left heart failure. In this report we describe an unusual patient with third-degree atrioventricular (AV) block unaccompanied by left ventricular dysfunction. Severe left ventricular dysfunction occurred 5 years after the implantation of a permanent pacemaker. We conclude that AV block should not be overlooked as an initial clinical manifestation of dilated cardiomyopathy.

Adult↗
PubMed1997

Heart rate variability and ventricular arrhythmia in clinically stable patients with hypertrophic cardiomyopathy.

To investigate whether autonomic nervous dysfunction exists and to determine the relationship between autonomic nervous activity and ventricular arrhythmias in clinically stable patients with hypertrophic cardiomyopathy (HCM), we studied heart rate variability (HRV) in 21 patients with HCM and 10 age-matched healthy control subjects. Patients were divided into 2 groups: HCM I (14 patients without nonsustained ventricular tachycardia, defined as 3 or more consecutive ventricular premature beats) and HCM II (7 patients with nonsustained ventricular tachycardia). HRV was measured on 24-h ECG monitorings using both nonspectral and spectral methods (fast Fourier transform, FFT). We assessed autonomic nervous activity based on high-frequency (HF; 0.15-0.40 Hz, an index of parasympathetic nervous activity) and the low- to high-frequency power ratio (L/H ratio; an index of sympathetic nervous activity) during daytime and night-time separately. There were no significant differences in any index of HRV between the HCM I and control groups. HF in the HCM II group was significantly lower than that of both the HCM I and control groups during the day and at night, whereas the L/H ratio at night-time was significantly higher in the HCM II group than in the HCM I and control groups. These data demonstrate that, in clinically stable HCM patients without nonsustained ventricular tachycardia, autonomic nervous activity was not different to that of healthy control subjects, whereas in HCM patients with nonsustained ventricular tachycardia, parasympathetic nervous activity was reduced throughout the 24-h period, and sympathetic nervous activity at night was increased compared with healthy control subjects. Thus, HCM patients with nonsustained ventricular tachycardia have to be treated even if they do not exhibit significant clinical manifestation.

Adult↗
PubMed1997

Reversible glomerular hypertrophy in adult patients with primary focal segmental glomerulosclerosis.

The present study was performed to assess the pathogenetic role of glomerular hypertrophy in patients with primary focal segmental glomerulosclerosis (FSGS). We studied 14 patients with FSGS by morphometry. In seven patients, minimal change nephrotic syndrome (MCNS) was diagnosed on the first renal biopsy, but FSGS was diagnosed on the second biopsy (MCNS-FSGS group). Seven other patients with FSGS on the first biopsy underwent second biopsies while in remission (FSGS-R group). Biopsy results were compared with biopsies from 10 patients with MCNS and seven control subjects. Nonsclerotic glomeruli were examined. The mean glomerular tuft area, whole glomerular area, and number of mesangial cells were significantly increased in both biopsies from the MCNS-FSGS group and in the first biopsies obtained during the nephrotic stage of the FSGS-R group, compared with control subjects and patients with MCNS. Biopsies from FSGS patients in remission showed that the mean glomerular tuft area and number of mesangial cells were significantly decreased. The fractional extracellular matrix area (extracellular matrix area/glomerular tuft area) and mesangial cell density (mesangial cell number/glomerular tuft area) in FSGS during both nephrotic and remission stages were the same as those in control subjects and patients with MCNS. The present study suggests that glomerular hypertrophy precedes the development of glomerulosclerosis in FSGS and is reversible when patients are in remission. These features support the pathogenetic importance of glomerular hypertrophy in patients with primary FSGS.

Adult↗
PubMed1997

[Successful treatment for pulmonary hypertension with angiotensin 1 converting enzyme inhibitor in a patient with mixed connective tissue disease].

This report described a 44 years-old female mixed connective tissue disease (MCTD) patient presenting pulmonary hypertension, successfully treated with angiotensin I converting enzyme (ACE) inhibitor. The patient was diagnosed as having MCTD because of Raynaud's phenomenon, swollen hand, and elevated level of anti-U 1 RNP antibodies. She was admitted to our hospital one year after the diagnosis of MCTD, because she experienced dyspnea and pretibial edema. A diagnosis of pulmonary hypertension was made by echocardiography and catheterization study. Pulmonary artery pressure and pulmonary artery resistance declined and returned gradually to normal during a period of three months with prednisolone and enalapril (10 mg/day) therapy. Pulmonary hypertension is one of fetal complications with MCTD, and 5 year mortality rate is reported less than 50%. However, a successful therapy for the pulmonary hypertension with MCTD has not been established yet. We considered that ACE inhibitor might be useful to control the pulmonary hypertension with MCTD and could improve the prognosis of MCTD.

Adult↗
PubMed1997

[Relationship between carotid atherosclerosis and plasma endothelin-1 concentration in senile patients with hypertension].

The relationship between carotid atherosclerosis and plasma endothelin-1 (ET-1) concentration was studied in senile patients with essential hypertension. A total of 212 patients (83 M, 129 F; mean age, 63 years) with essential hypertension (WHO stage I-II), and 109 age-matched control subjects (mean age, 61 years) were enrolled in the study. The maximum thicknesses of the intima-media complex (IMTmax) in the right common carotid artery (CCA) and the right internal carotid artery (ICA) was measured by B-mode ultrasonography, and ET-1 was measured by enzyme immunoassay. ET-1 levels were significantly higher in the hypertensive patients than in the control subjects. In middle-aged patients (35-64 years old), IMTmax values of the ICA in patients with high ET-1 concentrations (ET-1 > or = 1.71 pg/ml) were significantly higher than in patients with normal ET-1 concentrations (ET-1 < 1.71 pg/ml). However, the IMTmax of the CCA did not show a similar correlation. In senile patients (65-83 years old), both the CCA and ICA IMTmax values were significantly higher in patients with high ET-1 concentrations than in those with normal ET-1 concentrations. These results indicate that high ET-1 levels in middle-aged patients with essential hypertension may play a role in the progression of ICA atherosclerosis. High ET-1 levels in senile patients with essential hypertension may cause progression of atherosclerosis in both the ICA and CCA.

Adult↗
PubMed1997

[Effects of atherogenic risk factors on asymptomatic brain infarct].

This study was done to clarify the relationship between asymptomatic brain infarcts and risk factors for atherogenis. A total of 312 patients (151 men and 161 women) who had no neurologic deficits were enrolled. Their ages ranged from 41 to 83 years (mean age 63 years). The patients were divided into two groups: 158 patients without asymptomatic brain infarct and 154 patients with at least one asymptomatic brain infarct of at least 5 mm as diagnosed by magnetic resonance imaging. The patients with asymptomatic brain infarct were more likely than those without asymptomatic brain infarct to be 65 years old or older, and to have essential hypertension, diabetes mellitus, or atrial fibrillation. Among patients with hypertension the frequency of left ventricular hypertrophy or hypertensive ocular findings (Scheie's class H2) was significantly higher in those with asymptomatic brain infarct than in those without asymptomatic brain infarct. These results indicate that aging, essential hypertension (especially with left ventricular hypertrophy or hypertensive ocular findings), diabetes mellitus, and atrial fibrillation are associated with asymptomatic brain infarct.

Adult↗
PubMed1997

[The relationship between brain atrophy and asymptomatic cerebral lesions].

In order to clarify the relationship between brain atrophy and asymptomatic cerebral lesions, total of 235 subjects (130 males and 105 females), who had neither neurologic deficits nor organic lesions on cerebral computed tomography, were studied. The subjects' ages ranged from 40 to 86 years (mean 66). They were divided into two groups: 90 controls without hypertension or diabetes mallitus (Group C), and 145 patients with essential hypertension (Group H). Brain atrophy was diagnosed using the caudate head index (CHI). Asymptomatic cerebral lesions on magnetic resonance imaging were defined as asymptomatic lacunae and white matter lesions. Caudate head index was higher in Group H than it was in Group C, and CHI in both groups was significantly correlated with the number of asymptomatic lacunae and the severity of white matter lesions on magnetic resonance imaging. These results indicate that brain atrophy may progress along with asymptomatic cerebral lesions.

Adult↗
PubMed1997

A case report of midgut nonrotation treated by laparoscopic Ladd procedure.

We performed laparoscopic survey and treatment on a 17-year-old girl who was diagnosed as having complete midgut nonrotation. The Ladd procedure was successfully performed laparoscopically. The patient was discharged 6 days after the operation. Laparoscopic operation is a useful tool for the correct diagnosis and treatment of intestinal malrotation disease in the adult patient.

Adolescent↗
PubMed1997

Laparoscopic transhiatal esophagectomy for advanced thoracic esophageal cancer.

We performed transhiatal subtotal esophagectomy under laparoscopic guidance to reduce the invasiveness of subtotal esophagectomy while preserving dissectional accuracy. In six cases of advanced thoracic esophageal cancer with distant metastasis, we used a special type of handpiece of ultrasonic surgical aspirator (CUSA) for laparoscopic surgery to dissect the esophagus from surrounding tissues and to isolate vessels entering it while viewing with the video monitor. Hemostasis of isolated vessels was effected by clips or electrocoagulation. There was no massive bleeding from the mediastinum during the operation, nor was there postoperative bleeding or infection. All patients regained normal swallowing ability and were discharged. Transhiatal esophagectomy under laparoscopic guidance is considered a safe, less invasive operative treatment for patients who are suffering from advanced thoracic esophageal cancer.

Aged↗
PubMed1997

[Effects of physical training on autonomic nerve activity in patients with acute myocardial infarction].

The effects of early physical training on heart rate variability and autonomic nerve activity in acute myocardial infarction were studied in 20 patients (men, mean age 57 +/- 11 years) successfully treated by direct coronary angioplasty. Patients were randomly divided into the physical training group (training group: 10 patients) and conventional rehabilitation group (non-training group: 10 patients). Exercise tolerance (VO2 peak and anaerobic threshold: AT), heart rate variability indices, serum levels of catecholamines, and 24-hour urinary excretion of catecholamines were measured on the 14th and 28th days. The conventional cardiac rehabilitation program was followed by each group, and the training group patients were also instructed to follow a training program using the bicycle ergometer (80% AT, 10 min, 2 times a day) for 2 weeks from the 15th day. Autonomic nerve activity was assessed by non-spectral (24-hour averaged normal RR intervals: mean NN, standard deviation of normal RR intervals over 24 hours: SDNN and standard deviation of the mean RR intervals for each 5 min periods over 24 hours: SDANN) and spectral [high frequency power (HF) 0.15-0.40 Hz; represents parasympathetic activity, and the low/high frequency power (L/H ratio); represents sympathetic activity] indices of heart rate variability. There were no cardiac events during physical training. Comparison of the 14th and 28th day in the training group showed that the VO2 peak and VO2 AT significantly increased, SDNN and SDANN significantly increased, HF (82.5 +/- 56.2 to 131.1 +/- 99.8 msec2) increased and the L/H ratio (3.9 +/- 2.2 to 2.6 +/- 1.3) decreased significantly during the night-time, and serum noradrenalin concentration (0.47 +/- 0.11 to 0.35 +/- 0.13 ng/ml) and urinary noradrenalin excretion (195.6 +/- 130.7 to 139.6 +/- 73.3 micrograms/day) significantly decreased. In contrast, the non-training group showed no significant changes. These results suggest early physical training may be safe and improves the autonomic nerve balance and exercise tolerance in patients with acute myocardial infarction.

Aged↗
PubMed1997

[The effect of coronary intervention on renal function in patients with chronic renal failure].

To investigate the effect of coronary intervention on renal function in patients with chronic renal failure (CRF) we investigated 19 patients with CRF [serum creatinine (Scr) > 1.5 mg/dl] who underwent coronary intervention for the treatment of acute myocardial infarction or unstable angina recruited from 516 consecutive patients admitted to the coronary care unit of Nara Medical University Hospital from January, 1992 to July, 1995. Serum creatinine levels were measured at 3 points: on admission, at peak level, and at discharge. Nineteen patients were divided into two groups on the basis of increases in Scr (delta Scr): a worsened group (group A) (delta Scr > or = 1mg/dl after coronary intervention; 6 patients) and an unchanged group (group B) (delta Scr < 1 mg/dl ; 13 patients). In group A, except for one patient, the renal function recovered to the level before coronary intervention after adequate hydration or hemodialysis. The volume of contrast medium in group A (420 +/- 134 ml) was significantly higher than group B (253 +/- 97 ml) (p < 0.01). There was significant positive correlation (r = 0.42, p < 0.05) between delta Scr and the volume of contrast medium. In conclusion, coronary intervention for patients with CRF can be performed safely under treatment with adequate hydration and hemodialysis, even at higher serum creatinine levels of up to 4.0 mg/ml.

Aged↗
PubMed1997

[A case of necrotizing crescentic glomerulonephritis in which myeloperoxidase antineutrophil cytoplasmic antibodies (ANCA) reflect the disease activity and recognize various neutrophil cytoplasmic constituents].

This report describes a 50-year-old female with necrotizing crescentic glomerulonephritis (NCGN), associated with antineutrophil cytoplasmic antibodies (ANCA) recognizing various neutrophil cytoplasmic constituents. The patient was admitted to our hospital because of proteinuria. She had been well until seven months before admission, when she experienced fever and arthralgia. Tests for ANCA showed a p-ANCA pattern in indirect immunofluorescence, and high positivity for ANCA against myeloperoxidase (MPO) and lactoferrin in ELISAs. The renal biopsy on admission revealed crescentic glomerulonephritis with segmental necrosis. Therefore, we made the diagnosis of NCGN secondary to ANCA-associated renal disease. The second renal biopsy obtained after a period of 70 days with prednisolone and cyclophosphamide therapy displayed marked improvement indicating the disappearance of cellular crescents and necrosis lesions. Moreover, the levels of MPO-ANCA were correlated with the disease activity. We considered this patient to be a rare case of NCGN with ANCA recognizing various antigens. MPO-ANCA in this case might have been directly associated with the pathogenesis of NCGN.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1997

[Fulminant hepatic failure and liver transplantation].

Fulminant hepatic failure (FHF) is defined as the onset of grade II hepatic encephalopathy within 8 weeks after the onset of jaundice in patients whose prothrombin time is less than 40%. There are an estimated 3,700 cases of FHF in Japan. There are no specific therapies for FHF, however, liver transplantation is recommended for situations in which spontaneous recovery appears unlikely. The 1-year graft survival after liver transplantation for FHF is 65 to 80%. At present, orthotopic liver transplantation has become an accepted procedure for FHF. The advantages of auxiliary transplantation in FHF are the temporary requirement for immunosuppression drugs until the host liver recovers and the relative ease of surgery. Two types of auxiliary liver support are possible: heterotopic (APL) and orthotopic (APOLT). APLT is technically easier but suffers from competition between the graft and native liver for portal blood supply, problems of venous congestion and potential lack of space. However, APOLT has a more secure portal blood supply than APLT. Several technical problems with auxiliary transplantation need further evaluation.

Hepatic Encephalopathy↗