Biomedical subjects

M Sakuma

Publications and source records attributed to M Sakuma.

At least 55 records · Page 3Linked to original sources

PubMed1998

Surgical experiences with peripheral arterial aneurysms due to vasculo-Behçet's disease.

BACKGROUND: Vascular involvement of Behçet's disease is currently considered as an important sign of the clinical evolution of patients with Behçet's disease. In addition, Behçet's disease is important in that it causes peripheral arterial aneurysms. METHODS: In this report, 4 patients with vasculo-Behçet's peripheral arterial aneurysms are presented. These aneurysms were distributed in the carotid artery (n=1), popliteal artery (n=1) and femoral arteries (n=3). Operative procedures included patch closure of a perforated wall for the carotid aneurysm, arterial reconstruction with the autogenous saphenous vein for the femoral and popliteal aneurysms. RESULTS: All four patients tolerated the operation well, however, two of four patients required re-operation due to anastomotic insufficiency later. CONCLUSIONS: Aneurysms associated with Behçet's disease have a sudden onset in many cases and often result in rupture. Appropriate operative procedures, including an adequate choice of anastomotic sites and reinforcement of the suture, may reduce the incidence of complications in patients with arterial aneurysms due to Behçet's disease.

Adolescent↗

PubMed1997

Molecular evolution of myelin proteolipid protein.

We show that the major membrane protein of central nervous system myelin, proteolipid protein, evolved much more rapidly than it does now more than 300 million years ago. We reason that myelin proteolipid protein evolved rapidly just after its appearance in vertebrates and that its evolutionary rate then gradually decreased. Comparison of the rates between the synonymous and nonsynonymous nucleotide substitutions for the cDNA suggests the possibility that positive selection operated on myelin proteolipid protein at least when it appeared in vertebrates.

Amino Acid Sequence↗

PubMed1997

Schizophrenia as a chronic active brain process: a study of progressive brain structural change subsequent to the onset of schizophrenia.

Brain structural deviation is known to be present in chronic patients with schizophrenia when compared with normal age-matched individuals. While the assumption is that these differences are based on a neurodevelopmental disturbance, whether they are static or continue to change throughout the disease process remains unknown. The following report describes a prospective follow-up study of first episode cases of schizophrenic illness. Analyses of MRI evaluations on an approximate annual basis for a minimum of four years are presented on 50 patients and 20 controls. Computer-assisted image analysis measuring the volume of several brain regions, using the program ANALYZE (Mayo Clinic), was performed on all scans. Patients were compared with controls for the rate of change over time in size of structures. No differences were found for the volumes of the caudate nucleus, temporal lobes, or hippocampus; and no changes in the degree of cerebral laterality were detected. However, there was a significant difference in the rate of change in the overall volumes of left and right hemispheres (P < 0.0004 and 0.001, respectively), right cerebellum (P < 0.02) and area of the isthmus of the corpus callosum (P < 0.05). The left cerebral ventricle had significantly greater enlargement over time when measured on coronal slice sequences (P < 0.02), but was not detected by axial views. These findings suggest that a subtle active brain process may be continuing through the first few years of a schizophrenic illness causing greater than the normal adult cortical deterioration. Further studies using other methods of image analysis and over a longer period of time are needed to determine the course and nature of this biologic process.

Adult↗

PubMed1997

Language processing and memory in ill and well siblings from multiplex families affected with schizophrenia.

The present study was designed to extend the investigation of genetic factors for schizophrenia to cognitive and linguistic signs of central nervous system dysfunction. Of 51 siblings studied from 19 schizophrenia multiplex families, 37 had a DSM-III-R diagnosis of schizophrenia or related schzophrenia spectrum disorder and 14 were well. Controls were 17 unrelated healthy individuals within the same social class and age range. Subjects were tested on measures of memory, attention, reading and expressive language ability. Schizophrenic and spectrum disorder siblings were significantly more impaired in tests of auditory discrimination and memory than their well siblings or controls and displayed significantly reduced syntactic complexity to their speech. While well siblings did not differ from controls on most measures, some aspects of language complexity were reduced. A familial effect was observed for tests of reading ability, attention, some syntactic measures, and short-term memory, although these were not the measures that distinguished patients from controls in this cohort, the scores were not correlated among the ill sibling pairs, and poorer scores did not segregate with schizophrenia within these families. Thus, while some measures of language, memory and attention are deviant in patients with schizophrenia, they may not be heritable and directly related to the genetics of the disorder. Instead, they may be a manifestation of, rather than a vulnerability to, the illness.

Adult↗

PubMed1997

Induction of interleukin-2 unresponsiveness and down-regulation of the JAK-STAT system upon activation through the T cell receptor.

Full activation of T cells with antigen (Ag) and antigen-presenting cells initiates effector functions and proliferation. When T cells are re-stimulated through the T cell receptor (TCR) after a primary stimulation with Ag, growth arrest and cell death are induced. Activation of a T cell clone by cross-linking of TCR induces interleukin (IL)-2 unresponsiveness and ultimately cell death. While the proliferative signal delivered by IL-2 induces c-myc, bcl-2 and cyclin D3 expression, the expression of bcl-2 and cyclin D3 is completely suppressed upon TCR stimulation. Furthermore, TCR stimulation induces a decrease in the protein levels of JAK3 and STAT5, suggesting that IL-2 unresponsiveness and growth arrest of T cells result from down-regulation of JAK3 and STAT5.

Animals↗

PubMed1997

Extensive replacement of the aorta from the ascending aorta to the supraceliac abdominal aorta during a one-stage operation.

A successful replacement of the aorta from the ascending aorta to the supraceliac abdominal aorta in one operation is herein reported. The patient was 66-year-old woman who had DeBakey type I chronic aortic dissection with a pre-disseminated intravascular coagulation (DIC) condition. The image diagnosis revealed a markedly enlarged false lumen with a narrow true lumen in the ascending aorta extending to the diaphragm level while below the diaphragm level, the aortic dilatation was mild. The operation was performed through both a thoracoabdominal incision and a median sternotomy to expose the whole thoracic aorta, and the aorta was replaced from the ascending aorta to the supraceliac abdominal aorta. Selective cerebral perfusion was used for cerebral protection and this was a useful adjunct since no time limitations were thus required during repair of the aortic arch. Although the patient developed several complications postoperatively, she eventually recovered and was discharged from the hospital without any neurological disorders.

Aged↗

PubMed1997

Avulsion fracture of the metacarpophalangeal joint of the finger.

Six patients with avulsion fractures of the metacarpophalangeal joints of the fingers are reported. Operation was performed in all cases. Judging from the operative findings, the radiological assessment of fragment shape is helpful in treatment. Surgery is recommended when the fragment is triangular or rectangular in shape because the fracture involves the articular surface. Conservative treatment is effective if the fragment is round because the articular surface of the joint is not involved in this type of fracture. The avulsed fragment often overlaps the metacarpal head and a collateral ligament injury is likely to be misdiagnosed. It is important to suspect this injury and assess the shape of the whole fragment for a good functional result.

Adolescent↗

PubMed1997

Duplicated thumb bifurcation at the metacarpophalangeal joint level: factors affecting surgical outcome.

In order that the factors causing poor surgical outcome might be clarified, 175 duplicated thumbs bifurcating at the metacarpophalangeal joint level were analyzed. Cases were further divided into types A-D, based upon the details of the bifurcation form; that is, based on the connection of the radial digit to the ulnar components by either cartilage, joint, or fibrous tissue. The incidence of each type was 16% for type A (wide cartilaginous connection between phalanges), 68% for type B (2 separate phalanges), 6% for type C (cartilaginous connection to metacarpal), and 10% for type D (fibrous connection to joint capsule). Triphalangeal types and the relative size of the excised digit were determined by the preoperative radiograph. One hundred six cases were available for evaluation with a minimum of 3 years' follow-up. Good results were obtained in 50% of types A and C and in 80% of types B and D. Three phalanges in the preserve digits were observed in 10 cases and surgery on all but 1 resulted in a fair outcome. In cases where the size of the excised digit was more than 75% of the preserved digit, the results were fair or pool in 93%. The presence of subdivisions of types A and C, of 3 phalanges in the preserved digit, and of a relatively bigger excised digit were factors causing poor results, despite intensive reconstructive surgery.

Child, Preschool↗

PubMed1997

Reproducibility of home blood pressure measurements over a 1-year period.

We compared the reproducibility over time of blood pressure measured at the health examinations (screening blood pressure) and blood pressure measured at home (home blood pressure). Both screening and home blood pressure were measured in subjects of a rural community. Subjects measured their own blood pressure at home once in the morning using a semiautomatic oscillometric blood pressure measuring device at least three times (on at least 3 days) in each of two 4-week periods separated by one year. Similarly, two screening blood pressure measurements were obtained from the subjects at each of two health examinations also taken 1 year apart. A total of 136 untreated subjects without cardiovascular complications (40 men and 96 women, 56 +/- 11.7 years, mean +/- SD) were analyzed in the study. The correlations between the first and second blood pressure measurements of the subjects were significantly higher for the home blood pressure measurements (systolic: r = 0.844 and diastolic: r = 0.830) than for the screening blood pressure measurements (systolic: r = 0.692 and diastolic: r = 0.570). The mean differences between the first and second home blood pressure (0.8 +/- 7.7 mm Hg for systolic BP and 0.9 +/- 5.5 mm Hg for diastolic BP) were significantly smaller than those for the screening blood pressure (-3.9 +/- 13.8 for systolic BP and -3.1 +/- 10.2 for diastolic BP) (P < .001 for both comparisons), suggesting that the reproducibility of home blood pressure over time is superior to that of screening blood pressure. Such reliable blood pressure measurements obtained at home have a clinical significance for the diagnosis and treatment of hypertension and as a tool for evaluating the efficacy of antihypertensive drugs. Home blood pressure measurements also may be more useful than screening blood pressure measurements in predicting future cardiovascular events.

Adult↗

PubMed1997

A comparative study of 2',3'-cyclic-nucleotide 3'-phosphodiesterase in vertebrates: cDNA cloning and amino acid sequences for chicken and bullfrog enzymes.

In mammalian brain, two 2',3'-cyclic-nucleotide 3'-phosphodiesterase (EC 3.1.4.37) isoforms, CNP1 and CNP2, are translated, respectively, from the two mRNAs, which have been transcribed and processed by alternative use of the two transcription start points and by differential splicing. In the present study, the cDNAs encoding chicken CNP2 and bullfrog CNP1, respectively, were isolated, and the amino acid sequences of chicken CNP2 and bullfrog CNP1 were deduced. Western blot analysis showed that chicken brain contains a major CNP2-type protein together with a minor unidentified isoform, and bullfrog brain contains only a CNP1-type protein. All available amino acid sequences of vertebrate 2',3'-cyclic-nucleotide 3'-phosphodiesterases were aligned and compared. Three conserved motif sequences were noted: (a) an ATP-binding site near the amino terminus, (b) an isoprenylation site at the carboxyl terminus, and (c) a probable catalytic site resembling the active site of beta-ketoacyl synthase (EC 2.3.1.41). The second and the third motifs are conserved also in goldfish RICH (regeneration-induced 2',3'-cyclic-nucleotide 3'-phosphodiesterase homologue), which has been shown recently to have 2',3'-cyclic-nucleotide 3'-phosphodiesterase activity. The third motif (probably catalytic site) was assigned for the first time in the present report.

2',3'-Cyclic Nucleotide 3'-Phosphodiesterase↗

PubMed1997

Anomalous cerebral asymmetry and language processing in schizophrenia.

Reversal or reduction of normal structural cerebral asymmetries may be related to the pathogenesis of schizophrenia, but this relationship remains controversial. We review the literature and describe a further study designed to detect whether anomalous asymmetries are present early in the illness (at the first episode), whether they predict deficits in language processing, and whether they may be related to a genetic predisposition for schizophrenia. Asymmetries of brain widths and segments of the sylvian fissure were assessed in a magnetic resonance imaging study of 87 patients with a first episode of schizophrenia and 52 normal controls. These asymmetries were correlated with specific measures of language processing, memory, and hand skill. An independent group of 14 pairs of siblings with schizophrenia were also evaluated for evidence of heritability to cerebral asymmetries. Width asymmetries were reduced in patients compared with controls in the posterior (p = 0.02) and occipital (p = 0.05) regions. Brain horizontal length, on the other hand, was significantly more asymmetrical in patients (left > right; p = 0.04). For sylvian fissure measurements, asymmetries in controls (left > right) were greatest for the horizontal component; this asymmetry tended to detect differences in patients by comparison with controls (p < 0.06). In a range of tests of language and memory, few significant correlations between performance and cerebral asymmetries were detected either in patients or controls, although patients consistently scored poorer than controls in the majority of tests. In 14 pairs of psychotic siblings, within-pair correlations for the horizontal sylvian fissure asymmetry were significantly greater than between-pair correlations. These findings are consistent with the early presence (possibly genetic) of anomalous cerebral asymmetry. However, the functional correlates of reduced asymmetry remain obscure.

Adult↗

PubMed1997

Prediction of mortality by ambulatory blood pressure monitoring versus screening blood pressure measurements: a pilot study in Ohasama.

OBJECTIVE: To compare the prediction of mortality by ambulatory blood pressure monitoring and screening blood pressure measurements in a general population. DESIGN: A prospective cohort study. PATIENTS AND METHODS: We obtained blood pressure data for 1542 subjects (565 men and 977 women) aged > or = 40 years who were followed up for up to 8.1 years (mean 5.1 years). Subjects were subdivided into five groups according to their ambulatory and screening blood pressure levels. The prognostic significance of blood pressure for mortality was examined by the Cox proportional hazards regression model. RESULTS: The association between blood pressure level and mortality was more distinctive for the ambulatory blood pressure than it was for the screening blood pressure. The risk of cardiovascular mortality increased significantly for the highest quintiles of 24 h ambulatory blood pressure, whereas there was no significant association between the screening blood pressure and the cardiovascular mortality. When both 24 h and screening blood pressure values were included in the Cox model, only the systolic ambulatory blood pressure was related significantly to the increased risk of cardiovascular mortality. CONCLUSIONS: The ambulatory blood pressure had a stronger predictive power for mortality than did the screening blood pressure. This appears to have been the first study of the prognostic significance of ambulatory blood pressure monitoring versus screening blood pressure measurements in a general population.

Adult↗

PubMed1997

Inflammatory abdominal aortic aneurysms and atherosclerotic abdominal aortic aneurysms--comparisons of clinical features and long-term results.

A total of 274 patients with abdominal aortic aneurysms due to atherosclerosis (AAA) and 16 patients with inflammatory abdominal aortic aneurysms (IAAA) were reviewed to compare and contrast the clinical characteristics of the 2 groups. The AAA group comprised 243 men and 31 women with a mean age of 69.2 +/- 0.4 (range 51-86) years. The IAAA group comprised 15 men and 1 woman with a mean age of 67.4 +/- 2.0 (range 53-81) years. Most patients with IAAA (12/16; 75.0%) had pain at presentation, whereas only 37 out of 274 patients (13.5%) with AAA had pain (p < 0.001). Fifty out of 274 patients (18.2%) with AAA were asymptomatic, the most common principal complaint being a pulsatile tumor, which was found in 150 out of 274 patients (54.7%; p < 0.005 vs IAAA). Regarding laboratory findings of inflammation, preoperative erythrocyte sedimentation rate values were elevated in 15 out of 16 (93.8%) patients, and C-reactive protein values were elevated in 13 out of 16 (81.3%) patients with IAAA. The incidence of perioperative complications was similar in the 2 groups. The 30-day postoperative mortality among AAA patients was 6.2% (17/274 cases), including 12 cases of non-ruptured and 5 cases of ruptured AAA; in contrast, no early deaths occurred among patients with IAAA. The cumulative 5-year survival rate was 80.2% for IAAA patients and 74.6% for AAA patients (NS). The results of our review suggest that careful diagnosis and intra- and postoperative management could lead to patients with IAAA having a similar survival rate to those with AAA.

Aged↗

PubMed1997

Predictive value of home blood pressure measurement in relation to stroke morbidity: a population-based pilot study in Ohasama, Japan.

We investigated the utility of home blood pressure measurements for determining the risk of stroke. We also analyzed the relationship between home blood pressure and the incidence of stroke. Home blood pressure and screening blood pressure measurements were obtained from 1,789 residents (aged 40 yr or older) of a rural Japanese community. Blood pressure was measured at home with a semiautomatic device. A mean (+/-SD) of 23.0 +/- 7.5 measurements were made for each subject. Subjects without a history of stroke and who were not receiving medication for hypertension (n = 1,256) were prospectively followed up for 4.4 +/- 2.1 yr. Subjects were subdivided into quintiles according to their baseline blood pressure. The association between the baseline blood pressure and the incidence of the first-ever stroke was examined with the Cox proportional hazards regression model, adjusted for age and sex. The lowest risk of stroke morbidity occurred in the subjects in the third quintile for home systolic blood pressure (117-123 mmHg) and in those in the second quintile for home diastolic blood pressure (66-70 mmHg). The subjects in the fifth quintiles for home systolic (> or = 133 mmHg) and diastolic blood pressure (> or = 81 mmHg) had a significantly increased risk of stroke morbidity. The subjects in the first and the second quintiles for home systolic blood pressure and those in the first quintile for home diastolic blood pressure tended to have an increased risk as compared with subjects in the lowest risk groups, although this increase was not statistically significant, indicating two possibilities: a trend toward a J-shaped relationship or no-decrease in risk of the first-ever stroke in subjects with home blood pressure level less than 123/70 mmHg. This relationship was not observed for screening blood pressure. We conclude that home blood pressure measurements can provide additional prognostic information to that obtained from blood pressure measurement in a medical environment.

Adult↗

PubMed1997

The protein tyrosine kinases of the sea urchin Anthocidaris crassispina.

In order to know the function of protein tyrosine kinases (PTKs) in the development of sea urchin embryos, we performed reverse transcription-polymerase chain reaction (RT-PCR) to obtain partial cDNA fragments for PTK genes using primers to highly conserved regions of the PTK family. A total of seven PTK sequences were identified, two of which represented receptor PTK (RTK1 and RTK2), and five of which were non-receptor PTKs (NRTK1-5). RTK1 was highly similar to FGF receptor and Ret kinase, while RTK2 showed features of the insulin receptor family. NRTK1 and 2 belonged to the Src family and could be involved in egg activation at fertilization. NRTK3 showed the features of the Btk family kinases, while NRTK4 seemed to be a member of the Syk/ZAP70 family. NRTK5 is the Csk-type kinase of the sea urchin, which is known to negatively regulate the Src family kinases. RTK1 was not detected in unfertilized eggs and was activated after blastula stage. All the other PTK genes were expressed both maternally in unfertilized eggs and zygotically after fertilization, though each gene showed distinct temporal patterns.

Amino Acid Sequence↗

PubMed1997

A case of Klippel-Trenaunay syndrome associated with Huntington's disease.

We report here on a patient with Klippel-Trenaunay syndrome who was later diagnosed with Huntington's disease. Consistent with the later diagnosis, a (CAG)n repeat longer than the normal range was observed on chromosome 4p. The presence of these two diseases in the same individual may represent coincidence or a true correlation which must be confirmed by other evidence. To our knowledge, this is the first published report of the concurrent presence of these diseases in the same individual.

Humans↗

PubMed1997

Middle ear inflation as a treatment for secretory otitis media in children.

Clinical evaluations of middle ear inflation for secretory otitis media (SOM) were performed with special emphasis on the influence of seasonal and aging factors. One hundred and forty-nine children between the ages of 3 and 9 years (227 ears) were all diagnosed as SOM by pneumatic-otoscopic findings, and type B tympanogram (TG) at 3 weeks or more after the onset of acute SOM or the initial observation of SOM. Middle ears were inflated by Politzer's method or by our modified method once or twice each week for 2 months. After inflation, TG displayed two different time sequences: one group changed to the A or C type immediately after inflating the ear one or more times, but usually returned gradually to the B type (TG-improved group): and the other group remained without any changes (TG-unchanged group) for the duration of this study. The healing rate in the TG-improved group was significantly higher than in the TG-unchanged group at the 2-month endpoint. The cure rate of SOM was significantly higher in spring than in autumn in the TG-unchanged group but not in the TG-improved group. There were almost no differences between the healing rates in the 3-5 and 6-9 year-old children. When a TG-unchanged ear is found in autumn during the 2-month inflation treatment, more careful and forcible treatments should be introduced later, especially to children between the ages of 3 and 9 years.

Child↗

PubMed1997

Proposal of reference values for home blood pressure measurement: prognostic criteria based on a prospective observation of the general population in Ohasama, Japan.

The purpose of this study was to propose reference values, from a viewpoint of prognostic significance, for blood pressure (BP) measured at home with a semiautomated device (home BP measurement) to differentiate normotension and hypertension. We obtained home BP measurements for 1,913 population-based subjects aged 40 years and over in a rural Japanese community and followed up their survival for a mean duration of 5.0 years. There were 141 deaths during the follow-up period. The association between baseline BP values and the overall mortality was examined by Cox proportional hazards regression model, adjusted for age, gender, and the use of antihypertensive medication. The results indicated that the predictive power of home BP level for subsequent mortality was stronger than that of casual screening BP. There was a linear association between home systolic BP and mortality. The association between home diastolic BP and mortality was nonlinear and well approximated with the secondary degree equation of diastolic BP values. Based on this relation, we propose that the reference value for hypertension is 137/84 mm Hg, and normotension is below 137 mm Hg for home systolic BP and between 66 and 83 mm Hg for home diastolic BP. Home diastolic BP below 66 mm Hg should be considered as low diastolic blood pressure. In this population, home systolic BP of 137 mm Hg and home diastolic BP of 84 mm Hg corresponded to the 80th and 87th percentiles, respectively. Then, 29% of the subjects were classified as having hypertension, 52% as normotension, and 19% as low diastolic blood pressure. All previous studies proposing reference values for home BP measurement, derived from cross-sectional observations, were based on the statistical distribution of home BP values. The reference value must, however, be the one that best predicts the risk for morbidity and mortality from hypertension-related complications. This is the first report proposing reference values for home BP measurement based on prognostic criteria.

Adult↗