PubMed Health⌕ Search

Biomedical subjects

R Hashimoto

Publications and source records attributed to R Hashimoto.

At least 37 records · Page 2Linked to original sources
PubMed1996

Diagonistic dyspraxia. Clinical characteristics, responsible lesion and possible underlying mechanism.

We present three patients who showed, in addition to signs of callosal interruption, a variety of abnormal motor behaviour of the left hand dissociated from conscious volition, in the absence of pathological grasping phenomena. The abnormal movements of the left hand consisted of (i) antagonistic movements to the right; (ii) non-antagonistic, irrelevant movements to the right; (iii) symmetric movements to the right in which the left hand sometimes preceded the right, and (iv) occasional inability to move at will during a bimanual task. From these observations and a review of previous publications, we propose that, in most right-handed subjects; diagonistic dyspraxia could be defined as abnormal motor behaviour of the left hand activated by voluntary movements of the right hand. Motor phenomena similar to diagonistic dyspraxia but attributable to impulsive groping movements induced by medial frontal lobe pathology should be excluded from diagonistic dyspraxia. Comparison of MRIs of the three patients with those of five patients who developed no diagonistic dyspraxia following an infarction of the corpus callosum, with or without medial hemispheric involvement, revealed that damage to the ventral part of the posterior end of the body of the corpus callosum was crucial for the development of diagonistic dyspraxia. Since the commissural fibres between the superior parietal lobules pass through the caudal part of the body of the corpus callosum, and also since there is accumulating evidence that the human superior parietal lobule is concerned with selection of movement based on the integration of visual and/or somatosensory information, we infer that diagonistic dyspraxia is produced by a disconnection of the right superior parietal lobule from the left which is dominant for volitional control of movement in most right-handed subjects.

Apraxias↗
PubMed1996

Gigantic aneurysm in the thoraco-abdominal aorta of an infant.

We report the case of a boy with a gigantic aneurysm in the thoraco-abdominal region which was detected by a chest X-ray taken prior to surgical correction of ptosis of the eyelids at 11 months of age. At 18 months, he successfully underwent aneurysm exclusion and bypass grafting. A biopsy from the thoracic aorta revealed medial degeneration with conspicuous smooth muscle cell involvement. Laboratory examination showed altered elastase activity in the granulocytes and whole blood. The present case may represent a unique form of aneurysm in infancy.

Aortic Aneurysm, Abdominal↗
PubMed1996

Thoracoabdominal aortic aneurysm in an infant treated by thromboexclusion with thoracoabdominal aortic bypass. A case report.

A case of a huge thoracoabdominal aortic aneurysm in an eighteen-month-old boy is reported. Surgical treatment was successfully performed by thromboexclusion of the aneurysm with thoracoabdominal aortic bypass using a low-porosity woven Dacron graft 10 mm in diameter and of sufficient surplus length. During the early postoperative period, he developed moderate hydronephrosis, owing to compression of the left ureter by the graft, but no further deterioration was seen. Follow-up angiographies performed four and six years after surgery revealed straightening of the graft and slight stretching of the aorta at the distal anastomosis, but no stenosis was found. Now, seven and a half years after surgery, he has no pressure gradient between upper and lower extremities.

Angiography, Digital Subtraction↗
PubMed1996

Melanoxazal, new melanin biosynthesis inhibitor discovered by using the larval haemolymph of the silkworm, Bombyx mori. Production, isolation, structural elucidation, and biological properties.

A new melanin biosynthesis inhibitor, melanoxazal, was isolated from the fermentation broth of Trichoderma sp. ATF-451 by successive purification procedures of carbon adsorption, ethyl acetate extraction and silica gel column chromatography. The inhibitor possesses a novel oxazole-containing structure with molecular formula, C8H9NO3. The structure was determined by means of NMR analyses to be (E)-4-(2'-formyl-3'-hydroxybuten-1'-yl) oxazole, which is related to melanoxadin. Melanoxazal inhibited melanin formation in the larval haemolymph of the silkworm, Bombyx mori; IC50 value = 30.1 micrograms/ml. Melanoxazal also showed a strong inhibitory activity against mushroom tyrosinase with IC50 value = 4.2 micrograms/ml.

Animals↗
PubMed1996

[Preserved implicit reading and the recovery of explicit reading in a pure alexic].

We described a 55-year-old, right-handed, university-educated Japanese man who showed pure alexia after an infarction in the territory of the left posterior cerebral artery. Damage to the corpus callosum was limited to the most caudal part of the splenium. In the early days of his illness, he demonstrated the inability to read aloud on either Kana (Japanese syllabograms) or Kanji (Japanese morphograms). In contrast, he could semantically categorize Kanji-words such as animals or non-animals. Subsequently, he gradually regained the ability of reading aloud Kanji as well as Kana. At that time, we further investigated the relation between his reading ability and the attributes of 881 Kanji characters including hieroglyphicity, concreteness, and familiarity. We found that he could more readily read Kanjis with higher hieroglyphicity, concreteness, and familiarity. The reading times for Kanji-words were significantly shorter than those of corresponding Kana-words. Moreover, he showed some difficulty to read Kana-words and Kana combinations without meaning when asked to perform repetitive opposing movements with his thumb and little finger inhibiting kinesthetic reading. The effect was not observed when he read Kanji-words. These results lead us to suggest the following: (1) the two components of reading, reading aloud and comprehension abilities, are dissociable in a pure alexic, especially in Kanji reading; and (2) recovery mechanisms underlying Kanji and Kana reading were different in our case. Namely, restitution of the direct connection through the residual splenium fibers between the visual word form processing area in the right hemisphere and the left angular gyrus was attributed to Kanji reading, and utilization of kinesthetic reading played an important role in Kana reading.

Dyslexia, Acquired↗
PubMed1996

Hyperinsulinaemia as a predictor of hypertension: an 11-year follow-up study in Japan.

OBJECTIVE: To examine the hypothesis that hyperinsulinaemia is associated with the development of borderline hypertension or hypertension. DESIGN: Blood pressure status in non-obese normotensives (< 140/90 mmHg, n = 135) people were re-examined after 11 years after the baseline examination. Participants were selected from a 1981 population-based health examination and had a high blood glucose level or more than a trace of glucose in their urine. Out of 319 people recruited for further examination of glucose tolerance status, 135 normotensive participants with body mass index < 26 kg/m2 and without diabetes according to World Health Organization criteria were re-examined at the follow-up survey. RESULTS: Sixty-two (46%) out of 135 normotensive participants were hypertensive (defined as blood pressure > or = 140/90 mmHg) or receiving antihypertensive medication (n = 8) at the follow-up survey. Significant associations between the development of hypertension and baseline parameters were observed for systolic and diastolic blood pressure, serum triglycerides, high-density lipoprotein (HDL)-cholesterol, fasting and 60 min post-load insulin levels, and the sum of insulin concentrations from fasting to 180 min after glucose challenge after adjustments for age and sex. Odds ratios (95% confidence intervals) for the future development of hypertension between the highest and the lowest tertiles of insulin levels were 4.06 (1.40-11.76) for fasting insulin, 4.25 (1.45-12.45) for 60 min post-glucose load insulin, and 3.88 (1.34-11.20) for the sum of insulin concentrations, after adjustment for age, sex, systolic blood pressure, body mass index and alcohol consumption. Further adjustments for serum triglycerides and serum creatinine did not affect the insulin-hypertension relationship. CONCLUSION: The present study suggests that hyperinsulinemia is significantly related to the development of hypertension in non-obese and non-diabetic Japanese people.

Adult↗
PubMed1996

[A case of rapidly grown pulmonary blastoma].

A 78-year-old woman who had been in a local hospital with a complaint of cough and chest pain was referred to our hospital because a mass 12 cm in size was found in her right lung by a chest X-ray and CT. Within 3 weeks, the tumor rapidly developed to 19 cm in size. Malignant schwannoma of the lung was suspected by a percutaneus lung biopsy and the right upper and middle lobectomy was performed. Histological analysis of the tumor showed a biphasic structure with epithelial and mesenchymal component which was diagnosed pulmonary blastoma. Pulmonary blastoma is very rare, but it may be of benefit for the thoracic surgeon to establish methods of diagnosis and treatment of this disease.

Aged↗
PubMed1996

[Truncal valvoplasty for post-operative truncal valve regurgitation of truncus arteriosus: a case report].

The surgical treatment for truncal valve regurgitation is still controversial in patients with truncus arteriosus. A two-year-old girl with complaints of low weight gain and tachypnea was referred for treatment of truncal valve regurgitation. She had undergone an emergency pulmonary artery banding for severe congestive heart failure due to truncus arteriosus-type I at six months of age. This anomaly had been corrected by Barbero-Marcial method at seven months of age. But the truncal valve regurgitation started appearing at sixteen months of age with the progression of the stenosis of the pulmonary artery orifice and the right ventricular outflow tract regurgitation. Echo cardiography and cineangiography revealed the truncal valve to be bicuspid, and the regurgitation severe, especially through the prolapsed left sided cusp. The truncal valve was repaired by commissural suspension method, and the right ventricular outflow tract reconstructed with patch angioplasty of the pulmonary artery orifice and Carpentier-Edwards pericardial Bioprosthesis (19 mm). The post-operative course was uneventful. One year after, truncal valve regurgitation is small by color Doppler study. We conclude that valvoplasty is to be considered as the first choice of treatment for truncal valve regurgitation.

Child, Preschool↗
PubMed1995

N-terminal deletion mutants of insulin-like growth factor-II (IGF-II) show Thr7 and Leu8 important for binding to insulin and IGF-I receptors and Leu8 critical for all IGF-II functions.

To define the role of the N-terminal region of insulin-like growth factor-II (IGF-II) in its binding to insulin and IGF receptors, deletion mutants des-(1-5)-, des-(1-7)-, and des-(1-8)-recombinant (r) IGF-II, and the Gly8 for Leu substitution mutant of rIGF-II were prepared by site-directed mutagenesis, expressed in Escherichia coli, and purified. The binding affinity and mitogenic activity of these rIGF-II mutants as well as commercially available des-(1-6)-rIGF-II were analyzed. While the relative affinity of des-(1-5)- and des-(1-6)-rIGF-II for purified human insulin and IGF-I receptors remained at > or = 50% levels of that of rIGF-II, the affinity of des-(1-7)-rIGF-II decreased to approximately 10% and approximately 3%, respectively, of that of rIGF-II. When the octapeptide including Leu8 was removed prior to the Cys9-Cys47 intrachain bond, the relative affinity of this deletion mutant, des-(1-8)-rIGF-II, for these receptors dramatically decreased to < 1% of that of rIGF-II. Substituting Gly8 for Leu in rIGF-II decreased the affinity of this mutant for the IGF-I and insulin receptors to about the same extent. These results suggest that the side chains of Thr7 and Leu8 may play an important role in retaining all of the IGF-II functions. Decreases in the relative affinity for binding of the mutants to these receptors paralleled the decreases in their mitogenic potency for cultured Balb/c 3T3 cells. Although the relative affinity of des-(1-8)- or [Gly8]rIGF-II for rat IGF-II/CIM6-P (cation-independent mannose 6-phosphate) receptors was also < 1% of that of rIGF-II, the relative affinities of des-(1-5)-, des-(1-6)-, and des-(1-7)-rIGF-II for these receptors was significantly greater than that of rIGF-II. These results clearly demonstrate that Thr7 and Leu8 are important for binding to insulin and IGF-I receptors and Leu8 is critical for expression of all IGF-II functions.

3T3 Cells↗
PubMed1995

Purified horseshoe crab factor G. Reconstitution and characterization of the (1-->3)-beta-D-glucan-sensitive serine protease cascade.

Horseshoe crab hemocyte lysate responds to (1-->3)-beta-D-glucans, initiating an enzymatic cascade, which culuminates in clot formation. We have purified to homogeneity the serine protease zymogen factor G, which is directly activated by (1-->3)-beta-D-glucans and which initiates the hemolymph clotting cascade. Factor G is a heterodimeric protein composed of two noncovalently associated subunits alpha (72 kDa) and beta (37 kDa). In the presence of (1-->3)-beta-D-glucans such as curdlan and paramylon, factor G is autocatalytically activated to an active serine protease named factor G. This activation is accompanied by limited proteolysis of both subunits: the 72-kDa subunit alpha is cleaved to 55-kDa and 17-kDa fragments, and the 37-kDa subunit beta is shortened to 34 kDa. Longer incubations with (1-->3)-beta-D-glucans result in cleavage of the 55-kDa fragment to 46 kDa and the 34-kDa fragment to 32 kDa, with concomitant loss of amidase activity. Reconstitution experiments using purified proteins participating in the hemolymph clotting cascade demonstrate that factor G is capable of activating proclotting enzyme directly, resulting in the conversion of coagulogen to coagulin gel. Thus, purified factor G is shown to be the primary initiator of the (1-->3)-beta-D-glucan-sensitive coagulation pathway in the horseshoe crab hemocyte lysate.

Amino Acid Sequence↗
PubMed1995

Utilization behavior after right thalamic infarction.

We report a patient who showed exaggerated responses to external cues (utilization behavior), motor impersistence, and a right-hand-predominant instinctive grasp reaction after right thalamic infarction. High-resolution computed tomography with stereotaxic lesion localization revealed almost complete destruction of the ventroanterior nucleus and intralaminar nuclei of the right thalamus; the dorsomedial nucleus was only partially involved. Single photon emission computed tomography revealed hypoperfusion in the right thalamus and over the entire right cerebral cortex with some prominence in the frontal area. From these observations, we believe that the utilization behavior in our case was caused by the disturbance in maintaining cortical tone of the right hemisphere as well as by the dysfunction of the right frontal lobe, both secondary to the damage to the right ventroanterior nucleus and intralaminar nuclei.

Aged↗
PubMed1995

Relationship between associations of NOR and chromosomal anomalies in the abnormal embryos of nonobese diabetic and STZ-diabetic mouse.

Associations of nucleolar organizing regions (NORs) in the postimplantation stage embryos of nonobese diabetic (NOD) mice, and diabetic ICR mice induced by streptozotocin (ST), were studied to investigate the possible cause of the numerical anomalies of the chromosomes in their abnormal embryos. The incidence of NOR associations in abnormal embryos from diabetic NOD (NOD-DM) and STZ-diabetic mice was 11.7 and 7.7%, respectively. This incidence was significantly higher than that (1.2%, p < 0.05) of normal embryos from ICR mice which were used as control. From the results analyzed cytogenetically it was suggested that the higher incidence of chromosomal numerical anomalies in the embryos from NOD-DM and STZ-diabetic mice were caused by the chromosomal nondisjunction induced by associations of NORs. Furthermore, it was suggested that NOD-DM embryos have a tendency to increase the associations of NOR in a diabetic condition together with other factors such as autoimmune disease, however a diabetic condition alone induced chromosomal anomalies. Regarding relationships between the incidence of associations of NOR and the types of malformed embryos, it was also clear that all of the abnormal embryos from NOD-DM and STZ-diabetic mice had a high incidence of associations of NOR, and that the incidence was not related to the types of congenital anomalies. Furthermore, in the mal-developed tissue of embryos from STZ-diabetic mice, many chromosomal anomalies were found (26.6%), and the incidence was similar to that of whole embryos (22.6%).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Serum N-acetyl-beta-D-glucosaminidase activity in predicting the development of hypertension.

We conducted a prospective study in residents of a small farming community in southwestern Japan to determine whether elevated serum N-acetyl-beta-D-glucosaminidase (NAG) activity would predict future hypertension. The 505 normotensive subjects (blood pressure, < 140/90 mm Hg; mean age, 52 +/- 12 years) were reexamined after 7 years; 111 (22%) had become hypertensive (defined as blood pressure > or = 140/90 mm Hg and/or taking antihypertensive medication at follow-up). After adjustment for age and sex, the development of hypertension was significantly related to body mass index (P < .002), the sum of skinfolds (P < .001), baseline blood pressure (P < .0001), serum cholesterol (P < .01), serum uric acid level (P < .0001), and serum NAG activity (P < .005). Elevated NAG activity showed an independent relationship to future hypertension (P < .005) after adjustments for age, sex, baseline blood pressure (systolic, diastolic, or mean), uric acid level, and the sum of skinfolds. Therefore, elevated serum NAG activity was an effective indicator of future hypertension, and it might therefore be related to functional and/or structural changes in the cardiovascular system.

Acetylglucosaminidase↗
PubMed1995

Isolation and characterization of the IS3-like element from Thermus aquaticus.

We have cloned and characterized a genetic element (1187 bp) that is responsible for the induction of thermotolerance as well as ompC expression in E. coli. This element (ISLtaq1) was isolated from Thermus aquaticus. DNA and protein data bases were searched with this element (ISLtaq1), which suggested it to be very similar to IS150 belonging to the IS3 family. ORF1, found on ISLtaq1, which encodes 100 amino acids (aa), had a DNA-binding motif: a helix-turn-helix and a leucine zipper. In fact, when the ORF1 protein was overproduced in E. coli, thermotolerance as well as ompC expression was induced.

Adaptation, Biological↗