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Biomedical subjects

M Sakuma

Publications and source records attributed to M Sakuma.

At least 73 records · Page 4Linked to original sources
PubMed1997

Operative results of thoracoabdominal repair for chronic type B aortic dissection.

From January 1991 to May 1994, we have operated on 15 cases of Type B aortic dissection. In 10 of these patients, thoracoabdominal repair was performed. According to Crawford's classification, 2 patients fell into Type I, 6 patients into Type II, and 2 patients into Type III. The aneurysms were exposed through a left thoracotomy extending into the retroperitoneum with the hemidiaphragm divided circumferentially. The operations were performed under femoro-femoral partial cardiopulmonary bypass. In 6 of these cases selective perfusion of the visceral branches was used. The celiac axis was reconstructed in 10 patients, superior mesenteric artery in 9, right renal artery in 7, left renal artery in 6. Abdominal vessels were reconstructed by the "inclusion" technique described by Crawford in 2 patients, by "beveling" the distal prosthetic end in 6 and by the "interposition" technique in 4 patients. Vessels arising from the false lumen were reconstructed by the "interposition" technique. To prevent paraplegia, the evoked spinal cord potentials by direct stimulation of the cord (ESPs-dsc) were monitored perioperatively and the aneurysms were repaired sequentially in segments. In all patients except 2 with Crawford type III aneurysms, spinal cord ischemia was detected by ESPs-dsc. In 7 of these patients, 2 to 8 pairs of intercostal/lumbar arteries (I/L aa.) that arose from the "responsible" aortic segment were reconstructed. Reconstruction techniques included the "inclusion" technique in 2 patients, the "beveling" technique in 1, the "interposition" technique in 1 and the "on lay grafting" technique in 3 patients. One hospital death occurred in a patient who had chronic renal insufficiency and liver cirrhosis preoperatively. Spinal cord injury occurred in 5 patients, including 4 paraparesis and 1 delayed-onset paraplegia. In 2 of these patients, responsible I/L aa., were not reconstructed correctly despite ESPs changes, and injury might have been prevented if reconstruction of the "responsible" arteries had been performed. Thoracoabdominal repair for chronic Type B aortic dissection could be performed safely with an acceptable mortality rate. Spinal cord injury remains an unsolved problem.

Aortic Dissection↗
PubMed1997

The reliability of evoked spinal cord potentials elicited by direct stimulation of the cord as a monitor of spinal cord ischemia during temporary occlusion of the thoracic aorta.

Paraplegia is a severe and disastrous complication of operations on the thoracic aorta. For preventing this complication, we employed evoked spinal cord potentials elicited by direct stimulation of the cord (ESPs-dsc) during operations on 83 patients with various aortic lesions (37 dissecting and 46 cases of nondissecting aneurysms, 35 descending and 48 thoracoabdominal aortic aneurysms). All of the patients had some form of circulatory adjunct during aortic cross-clamping. Of the 83 patients, three had "immediate" paraparesis and five had "immediate" paraplegia, whereas three other patients had "delayed" paraplegia. During operation, four types of ESPs-dsc response pattern were observed: (1) no change (n = 57), (2) change with return (n = 15), (3) change with inconsistent return (n = 6), (4) change without return (n = 5). "Delayed" paraplegia occurred in two patients with "no change" and "change with return" response (3%), "immediate" paralysis occurred in three and "delayed" paraplegia occurred in one of those with "change with inconsistent return" response (67%), and all of those with "change with inconsistent return" response (67%), and all of those with "change without return" response developed "immediate" paraplegia (100%). We conclude that intraoperative monitoring of spinal cord function utilizing ESPs-dsc is a good indicator of spinal cord ischemia and we can improve the outcome according to its changes.

Aorta, Thoracic↗
PubMed1997

Mycotic aneurysm of the bilateral tibioperoneal trunks associated with bacterial endocarditis: a case report.

Since antibiotics have been widely used in the treatment of bacterial endocarditis, mycotic aneurysms caused by septic emboli have become extremely rare. We report the case of a 34-year-old man who had mycotic aneurysms in the tibioperoneal trunks of both legs six weeks after he had a mitral valve replacement due to Streptococcus viridans endocarditis. Color Doppler sonography was used to diagnose pseudoaneurysms in both legs. Surgical treatment included the closures of the orifices of both aneurysms in both legs and arterial reconstructions were not required. In the literature, however, the location of mycotic aneurysms in peripheral arteries related to endocarditis were usually reported to be in the upper extremities or femoral arteries. Thus, we present the extremely rare case of mycotic aneurysms because the aneurysms occurred in the infrapopliteal vessel and developed in both legs.

Adult↗
PubMed1996

Functional asymmetries in schizophrenia and their relationship to cognitive performance.

Previous accounts of cerebral dominance in schizophrenic patients have been conflicting. While many studies report decreased patterns of functional laterality in schizophrenic subjects, others report increases or no differences. Conceptual differences in the definition of laterality and its effects on behavior may be a reason for the poor concordance among studies. The present report addresses some of these problems and examines the hypothesis that schizophrenia may be associated with an alteration in normal patterns of functional laterality. In addition, the relationship between patterns of laterality and cognitive functioning was assessed. Twenty-one schizophrenic patients and 24 control subjects, all right-handed, were compared on two neuropsychological batteries, one designed to test cerebral dominance and the other, cognitive performance. Cerebral dominance was measured by two dichotic listening tests (verbal and nonverbal) and three motoric tests. Cognitive ability was assessed with a comprehensive neuropsychological battery. Schizophrenic and control subjects differed significantly in performance on laterality measures, but they did not differ in patterns of functional laterality when performance was taken into account. In addition, it was shown that the relationship between cognitive ability and laterality is complex, with some aspects of laterality appearing to be beneficial to cognitive ability.

Adult↗
PubMed1996

Circadian blood pressure variation related to morbidity and mortality from cerebrovascular and cardiovascular diseases.

The mortality rate of stroke has decreased dramatically over the past 30 years in Japan, but the prevalence of cerebral infarction has increased, mainly because of the higher incidence of nonfatal cerebral infarction in the elderly. Significant advances in the development of antihypertensive drugs over the last 30 years have contributed to the decrease in stroke mortality, but antihypertensive treatment appears to relate to an increase in the prevalence of cerebral infarction in the elderly. We investigated the risks of low BP levels determined by ambulatory BP monitoring and home BP measurements to clarify the previously reported J-shaped relationships between the incidence of ischemic cardiovascular disease and BP levels after treatment. A long-term prospective study of all causes of mortality and cerebrovascular and cardiovascular mortality has been conducted in Ohasama, Japan, since 1987. Cox proportional hazard model after adjusting for age and sex demonstrated that during a 5-year follow-up period involving 893 of the subjects aged 50 years and over in this cohort, those with the lowest quintile of ambulatory BP levels exhibited a significantly high hazard ratio of cardiovascular as well as all causes of mortality. During the same follow-up period in 1,226 subjects aged 50 years and over, those with the lowest and highest quintiles of home BP levels demonstrated a significantly high hazard ratio of cardiovascular as well as all causes of mortality (i.e., J-shaped relationship). The amplitude of the fall in nocturnal BP obtained by ambulatory BP monitoring correlated positively with the severity of silent cerebrovascular lesions in elderly women, but not in elderly men. These results suggest the significantly high risk associated with low BP levels, which can be determined only by ambulatory and home BP measurements, but not by casual BP measurements.

Age Factors↗
PubMed1996

The natural history of scaphoid non-union. Radiographical and clinical analysis in 102 cases.

A retrospective radiographic and clinical analysis of 102 symptomatic patients with 104 scaphoid nonunions of at least 1 year's duration was conducted. Osteoarthritis occurred in 22% of non-unions of less than 5 years' duration, 75% of those of 5 to 9 years' duration, and 100% of those of 10 years' duration or more. An all-over incidence of osteoarthritis in the wrist was 55%. Osteoarthritic changes occurred initially at the scaphoid-radial styloid joint which were manifested by radial styloid pointing and/or dorsal radioscaphoid osteophyte formation, later progressing to the midcarpal joint. Osteoarthritis at the scaphoid-radial styloid joint was significantly associated with dorsiflexed intercalated segment instability (DISI) deformity. An overall incidence of DISI deformity of the wrist was 56%, and the frequency of DISI pattern increased with longer duration of non-union. There was an increased incidence of avascular necrosis of the proximal fragment with time, especially after 20 years. There was no correlation between symptoms of pain and the severity of arthritis or the duration of non-union, but a good correlation between the duration of non-union and reduced grip strength or decreased wrist motion. A symptomatic non-union of the scaphoid is significantly likely to progress to osteoarthritis according to a predictable sequence, becoming worse both radiographically and clinically with time.

Adolescent↗
PubMed1996

Synthesis of some analogues of blattellastanoside A, the steroidal aggregation pheromone of the German cockroach.

Blattellastanoside A, the aggregation pheromone of the German cockroach, is a chlorinated steroid glucoside with the 5 beta-stigmastane skeleton. Its analogues were synthesized in order to clarify the structure-activity relationship. They are 1a with the 5 beta-cholestane skeleton, 1b with the 5 beta-androstane skeleton, 1c with a fluorine substituent instead of the chlorine and 1d with a beta-D-galactopyranose instead of the beta-D-glucopyranose of the original pheromone. Their bioassay shows that 1a and 1c are active, while 1b and 1d are totally devoid of pheromone activity. The aglycone of blattellastanosides A and B were active.

Animals↗
PubMed1996

Giant mixed tumor of the face.

A 35-year-old Japanese man consulted our clinic with an eight year history of a 6 cm diameter subcutaneous tumor on the left cheek. Hematoxylin and eosin staining of the resected section showed histology corresponding to a benign chondroid syringoma. Keratin was positive in most of the constituent cells, and S-100 protein was positive in the cells distant from the lumens and in myxomatous cells. A benign chondroid syringoma of this size has only been very rarely reported in the literature.

Adenoma, Pleomorphic↗
PubMed1996

Nocturnal blood pressure and silent cerebrovascular lesions in elderly Japanese.

BACKGROUND AND PURPOSE: We conducted a cross-sectional epidemiological survey using ambulatory blood pressure monitoring and brain MRI in a cohort from northern Japan to determine whether an inappropriately low nocturnal blood pressure, or an excess fall in nocturnal blood pressure, might be responsible for silent cerebrovascular lesions in the elderly. METHODS: Untreated subjects over 55 years and under 64 years of age (late middle age; 24 men and 46 women, 60% of eligible people) and over 65 years and under 75 years of age (elderly; 29 men and 52 women, 91% of eligible people) participated in the study. We evaluated the relationship between the amplitude (Daytime Average-Nighttime Average) or the rate ([Daytime Average-Nighttime Average]/Daytime Average) of the fall in nocturnal blood pressure and the incidence of silent cerebrovascular lesions on MRI (number of lacunar infarctions or extent of periventricular hyperintensity). RESULTS: The amplitude or the rate of the fall in nocturnal blood pressure in elderly women with one or two lacunar infarctions was significantly higher than that in those without such infarctions. There was a significant positive correlation between the amplitude or the rate of the fall in nocturnal blood pressure and the extent of periventricular hyperintensity in the elderly women. This relationship was observed in women, but not in men, of late middle age; this was not seen in elderly men. CONCLUSIONS: Results indicate that an inappropriately low nocturnal blood pressure, or an excessive fall in nocturnal blood pressure, is associated with ischemic silent cerebrovascular lesions, at least in elderly women. Treatment of hypertension in such women should be administered with care and with regard to nocturnal blood pressure.

Age Distribution↗
PubMed1996

Ambulatory blood pressure monitoring in evaluating the prevalence of hypertension in adults in Ohasama, a rural Japanese community.

We estimated the prevalence of hypertension and evaluated the degree of blood pressure control on the basis of ambulatory blood pressure monitoring in patients receiving antihypertensive medication. A total of 969 adults (mean age +/- SD, 59.3 +/- 12.1 years old range: 20-79 yr) among 1,575 eligible persons (65.1%) recruited from a total adult population of 2,789 people living in a rural region of northern Japan underwent measurement of initial screening blood pressure; ambulatory blood pressure was measured subsequently. A total of 285 subjects (66.5 +/- 9.2 years old) were taking antihypertensive medication (treated group), while 684 (56.3 +/- 12.0 years old) were not (untreated group). The WHO criteria were used to categorize screening blood pressure. Ambulatory blood pressure levels were classified as follows: hypertension, systolic blood pressure > or = 144 mmHg and/or diastolic blood pressure > or = 85 mmHg; and normotension, systolic blood pressure < or = 133 and diastolic blood pressure < or = 78 mmHg. Of the 285 treated subjects, 49 (17.2%) were classified as hypertensive by screening measurements, while 36 (12.6%) were classified as such by ambulatory blood pressure monitoring. Only 12 (24.5%) of the former 49 subjects were also classified as hypertensive, while 20 (40.8%) were classified as normotensive by ambulatory blood pressure monitoring. Of the 684 untreated subjects, 34 (5.0%) were hypertensive by screening measurements and 43 (6.3%) were hypertensive by ambulatory blood pressure monitoring. Only 14 (41.2%) of the former 34 subjects were classified as hypertensive by ambulatory blood pressure monitoring. Of the 34 untreated subjects classified as hypertensive by screening measurements, ambulatory blood pressure monitoring showed 12 (35.3%) to be normotensive, suggesting that they were cases of "white coat" hypertension. The study first confirmed, based on community-derived data, that there are large discrepancies between screening (casual) blood pressure measurements and ambulatory blood pressure monitoring with respect to the recognition of hypertension and normotension. The determination of blood pressure levels by ambulatory blood pressure monitoring may result in a different prognosis of hypertension from that made on the basis of screening blood pressure measurements. The prognostic value of ambulatory blood pressure has to be further investigated.

Adult↗
PubMed1996

A new method for evaluating right ventricular dimensions and volume by cineangiography.

The aim of the present study was to establish a new method to evaluate the right ventricular dimensions and volume. Biplane right ventriculography of steep left anterior oblique view (LAO) and right anterior oblique view perpendicular to LAO were performed in 32 patients. The right ventricular volume and ejection fraction calculated from the three axial dimensions of the right ventricular cavity (the septum-free wall dimension, the anterior-posterior dimension, and either the long axis dimension or the tricuspid valve-apex dimension at end-diastole and end-systole) were well correlated to those from Simpson's method. In conclusion, we developed a new method for estimating right ventricular dimensions and volume.

Adolescent↗
PubMed1996

Prevalence of hypertension and rate of blood pressure control as assessed by home blood pressure measurements in a rural Japanese community, Ohasama.

A cross-sectional community survey using home blood pressure measurements was performed in northern Japan to estimate the prevalence of definite hypertension, white coat hypertension and the success of blood pressure control in patients receiving antihypertensive drugs. A total of 1334 subjects (mean age +/- SD, 53.8 +/- 17.3 years; 8-91 years) participated in the screening and home blood pressure measurement program. They measured blood pressure at home at least 3 times (mean measurement frequency, 20.8 +/- 8.3 times). Of these 1334 subjects, 314 (65.1 +/- 8.9 years) were taking drugs (treated group) while 1020 (50.3 +/- 17.8 years) were not (untreated group). The WHO criteria were used to categorize screening blood pressure. Criteria for diagnosis of hypertension by home blood pressure measurements were as follows: definitely hypertensive (systolic blood pressure > or = 144 mmHg and/or diastolic blood pressure > or = 89 mmHg) and normotensive (104 < systolic blood pressure < or = 131 mmHg and 60 < diastolic blood pressure < or = 79 mmHg). Of the 1018 subjects identified as normotensive on screening measurements, home measurements indicated that 73 (7.2%) were hypertensive and 765 (74.7%) were normotensive or lower. Of the 112 subjects identified as hypertensive on screening measurements, home measurements showed that 42 (37.5%) were hypertensive and 30 (26.8%) were normotensive or lower. Of the 314 treated subjects, 45 (14.3%) were identified as hypertensive by screening measurements and 88 (28.0%) as hypertensive by home measurements. Only 20 (44.4%) of the former 45 subjects were also defined as definitely hypertensive by home measurements. Of the 1020 untreated subjects, 67 (6.6%) were hypertensive by screening measurements and 84 (8.2%) by home measurements. Only 22 (32.8%) of the former 67 subjects were classified as hypertensive by home measurements. Of the 67 untreated subjects identified as hypertensive by screening measurements, 20 (29.9%) were normotensive or lower by home measurements, suggesting that these subjects were "white coat" hypertensives. The study first confirmed based on the large community data that there are large discrepancies between screening (casual) blood pressure and home blood pressure measurements for recognition of hypertension and normotension. Determination of blood pressure levels by home blood pressure measurements may predict prognosis of hypertension differently from that by screening blood pressure measurements. Further prospectively study is needed to validate the prognostic value of home blood pressure measurements.

Adolescent↗
PubMed1996

Predictive power of screening blood pressure, ambulatory blood pressure and blood pressure measured at home for overall and cardiovascular mortality: a prospective observation in a cohort from Ohasama, northern Japan.

OBJECTIVE: To investigate the risks of high and low blood pressure levels determined by ambulatory blood pressure monitoring and home blood pressure measurements. METHODS: A long-term prospective study of all-cause mortality and cardiovascular mortality has been conducted in Ohasama, Japan since 1987. RESULTS: The Cox proportional hazards model after adjusting for age and sex demonstrated that, during a 5-year follow-up period involving 893 of the subjects aged 50 years or more in this cohort, those with the lowest quintile of ambulatory blood pressure levels exhibited a significantly higher hazard ratio for cardiovascular and for all-cause mortality. During the same follow-up period, of 1226 subjects aged 50 years and more, those with the lowest and highest quintiles of home blood pressure levels demonstrated a significantly higher hazard ratio with respect to cardiovascular and all-cause mortality (i.e., a J-shaped relationship). CONCLUSION: These results suggest that there is a significant risk associated with low blood pressure levels, which can be determined by ambulatory and home blood pressure measurements, but not by casual blood pressure measurements.

Journal Article↗
PubMed1996

[Dissection of the interventricular septum with aorto-left ventricular communication due to infective endocarditis--report of a rare case].

Dissection of the interventricular septum is an uncommon manifestation, which is rarely associated with infective endocarditis, aneurysm of sinus of Valsalva and thoracic trauma. We report a 34-year-old male case with aorto-left ventricular communication due to infective endocarditis. The patient had chief complaints of dyspnea on exertion and precordial discomfort. Preoperative laboratory data showed normal white blood cell counts, a slightly elevated CRP, and negative blood culture in bacterial examinations. Echocardiogram revealed progressive dissection of the interventricular septum and stenosis of the left ventricular outflow tract. Disturbance of conduction including progressive atrioventricular block and bundle branch block were found in the electrocardiogram. The dissection extended over 2 x 2 x 2.5 cm in diameter, with an entry located at the basis of the right coronary cusp and reentry communicated to the left ventricle. Operative procedures included the aortic valve replacement with prosthetic valve due to severe inflammation, in addition to resection of the dissecting cavity. Pathological examination of the resected tissue accorded with infective endocarditis in active phase, showing necrosis, small cell infiltration and microabscess. However, a bacterial colony was not found in the surgical specimen. Postoperative course was uneventful and the patient was discharged in satisfactory conditions.

Adult↗
PubMed1996

[Subtotal aortic replacement in a patient with Marfan's syndrome--replacement of the ascending aorta and entire aortic arch for acute type I aortic dissection 4 years after the thoracoabdominal replacement].

We report a patient with Marfan's syndrome who underwent replacement of the ascending aorta and the entire aortic arch for acute type I aortic dissection 4 years after the thoracoabdominal replacement. As a result, she underwent subtotal aortic replacement from the ascending aorta to the bilateral common iliac arteries in three stages. A 48-years-old female was admitted to our service because of acute heart failure and cardiogenic shock caused by acute DeBakey type I aortic dissection. She had undergone replacement of the descending thoracic aorta at the age of 44 and replacement of the remaining thoracoabdominal aorta with reimplantation of the four major abdominal branches at the age of 46 for a chronic expanding DeBakey type IIIb dissecting aneurysm. She successfully underwent replacement of the ascending aorta and the entire aortic arch with an aortic prosthesis provided with four branch grafts for reconstruction of the arch vessels. Considering the high incidence of new aortic lesion, extensive aortic replacement and careful postoperative follow-up are necessary in patients with Marfan's syndrome.

Aortic Dissection↗