Biomedical subjects

J Ono

Publications and source records attributed to J Ono.

At least 91 records · Page 5Linked to original sources

PubMed1997

Postoperative stability after sagittal split ramus osteotomy with condylar-positioning appliance and screw fixation: asymmetric versus symmetric cases.

OBJECTIVE: The purpose of this study was to evaluate postoperative stability in prognathic patients with mandibular asymmetry who were treated with sagittal split ramus osteotomy of the mandible. STUDY DESIGN: Ten asymmetric (group I) and 11 symmetric (group II) patients were examined. An appliance for repositioning the proximal segment was applied, and the bony segments were fixed with titanium screws. Cephalograms were obtained preoperatively, 2 to 3 days postoperatively, and 3 and 6 months after surgery. Changes in the positions of the standard points were examined on lateral cephalograms, and changes in the widths of the gonion points were examined on posteroanterior cephalograms. RESULTS: Statistical analysis revealed no significant difference between the two groups. In addition, there was no significant difference between the postoperative changes in the widths of the gonion points on the deviated and nondeviated sides in group I. CONCLUSIONS: This study suggests that application of an appliance for repositioning the proximal segment can minimize postoperative skeletal changes in patients with asymmetry.

Adolescent↗

PubMed1997

Direct evidence for the contribution of B cells to the progression of insulitis and the development of diabetes in non-obese diabetic mice.

The non-obese diabetic (NOD) mouse is an excellent animal model of autoimmune diabetes associated with insulitis. The progression of insulitis causes the destruction of pancreatic beta cells, resulting in the development of hyperglycemia. Although it has been well documented that T cells are required for the development of insulitis and diabetes in NOD mice, the importance of B cells remains unclear. To clarify the role of B cells in the pathogenesis of NOD mice, we therefore generated B cell-deficient NOD (B-NOD) mice. Surprisingly, none (of 13) of the B-NOD mice developed diabetes by 40 weeks of age, while the control littermates with B cells (B+NOD) suffered from a high proportion (43 of 49) of diabetes. The insulin reactivity of B+NOD mice was significantly impaired, while the B-NOD mice showed a good insulin response, thus suggesting the pancreatic beta cell function to be well preserved in B-NOD mice. Although B-NOD mice did develop insulitis, the extent of insulitis was significantly suppressed. These data thus provide the direct evidence that B cells are essential for the progression of insulitis and the development of diabetes in NOD mice.

Animals↗

PubMed1997

Contralateral external carotid-middle cerebral artery bypass for carotid artery resection.

Resection of the common carotid or internal carotid artery is occasionally unavoidable in cases of advanced head and neck carcinoma with carotid artery involvement. To prevent the consequent decrease in cerebral perfusion, we have developed a contralateral external carotid-middle cerebral artery bypass grafting technique. From 1990 through 1995, six patients with advanced head and neck cancer involving the carotid artery underwent total tumor resection combined with vascular reconstruction using the contralateral external carotid- middle cerebral artery bypass grafting. No bypass-related complications occurred in any patient postoperatively. Cerebral hemodynamics after surgery indicated that this bypass graft worked steadily over a long term and supplied sufficient volume of blood to the cerebral cortex on the opposite side in every case.

Adult↗

PubMed1997

Zonisamide monotherapy in newly diagnosed infantile spasms.

PURPOSE: We determined the short-term efficacy of zonisamide (ZNS) monotherapy in newly diagnosed patients with infantile spasms (IS). METHODS: Eleven hospitals participated in this open, prospective trial. ZNS 3-10 mg/kg/day was administered as the second-choice drug to 11 newly diagnosed patients with IS (cryptogenic 3, symptomatic 8) who failed to respond to high-dose vitamin B6. RESULTS: Four infants with symptomatic IS had cessation of spasms and disappearance of the hypsarrhythmia. In these responders, the spasms ceased after a few days (1-5 days) of treatment at a dose of ZNS 4-5 mg/kg/day which produced plasma ZNS concentrations ranging from 5.2 to 16.3 microg/ml (mean 9.8 microg/ml). There were two relapses (50%) 4-6 weeks after cessation of seizures, however. Relapse was predicted by effects of ZNS on EEG; the 2 infants in whom an abnormal EEG persisted had relapses, whereas the 2 whose EEG normalized remained seizure-free (follow-up 20 and 26 months). No adverse reactions were noted. CONCLUSIONS: ZNS may be effective in the initial treatment of selected patients with IS.

Adrenocorticotropic Hormone↗

PubMed1997

Is family history an independent risk factor for stroke?

OBJECTIVE: To estimate the influence of family history on the occurrence of stroke. METHODS: A case-control study was carried out from August 1992 to January 1994. The study population comprised 502 patients with a first stroke, aged between 20 and 70 years, who were treated at 48 affiliated hospitals. The same number of age and sex matched controls were selected from outpatients. Diagnoses were based on CT findings and clinical signs. There were 155 case-control pairs for subarachnoid haemorrhage, 158 for intracerebral haematoma, and 159 for cerebral infarction. Information about the patients and their families was obtained from a questionnaire which included the family histories of each subtype of stroke and other potential risk factors for stroke. The data were analysed focusing on the role of the family histories in the occurrence of stroke. RESULTS: In univariate analysis, the family histories of subarachnoid haemorrhage and intracerebral haematoma were positively associated with each of the subtypes of stroke (odds ratios 11.24 for subarachnoid haemorrhage, 2.39 for intracerebral haematoma), whereas family history of cerebral infarction was not a significant risk factor for its occurrence (odds ratio 1.41). Family history of intracerebral haematoma was correlated with a personal history of hypertension and habitual alcohol consumption. After adjustment for potential risk factors (hypertension, diabetes, hyperlipidaemia, obesity, alcohol consumption, and regular smoking), family history of subarachnoid haemorrhage still remained the most powerful risk factor for subarachnoid haemorrhage, whereas family history of intracerebral haematoma no longer showed a significant association with haematoma. CONCLUSION: Genetic factors play a major part in the pathogenesis of subarachnoid haemorrhage, and family history of subarachnoid haemorrhage is the strongest independent risk factor for the disease. On the other hand, family history of intracerebral haematoma was not an independent risk factor for haematoma, but it might be a good predictor, which indirectly influences the pathogenesis of intracerebral haematoma via certain hereditary components such as hypertension, and even lifestyle factors such as alcohol consumption. In cerebral infarction, genetic factors play a minor part in its pathogenesis.

Adult↗

PubMed1997

Band heterotopia or double cortex in a male: bridging structures suggest abnormality of the radial glial guide system.

A moderately retarded Japanese boy, with a normal male karyotype (46,XY), was diagnosed to have a subcortical band heterotopia or double cortex syndrome. The band heterotopia was relatively thick compared with that of other patients reported. On T2-weighted coronal MR sections, there were numerous radial linear structures between the cortex and the band, probably representing the trace of radial fibers. He had no family members with seizures or mental retardation. Over 50 described patients with this malformation have been female except two patients briefly mentioned by several investigators. Band heterotopia or the double cortex syndrome is inherited as a sex-linked dominant condition. Affected mothers may have affected daughters or sons with lissencephaly, suggesting a link between these disorders. This is the first detailed description of a male with band heterotopia.

Cell Movement↗

PubMed1997

Synthesis and antitumor activity of fused quinoline derivatives. IV. Novel 11-aminoindolo[3,2-b]quinolines.

Indolo[3,2-b]quinoline derivatives (1) having various amine moieties were prepared and their antitumor activities against P388 leukemia in mice were evaluated, for the purpose of gaining an insight into the role of the amine moiety in the antitumor activity and searching for an effective amine moiety. Introduction of a methylene group between the phenyl group and amino or methanesulfonamido group resulted in decrease or loss of activity.

Animals↗

PubMed1997

[Dural arteriovenous malformation presenting venous ischemia].

We report three patients with dural arteriovenous malformation (DAVM) in the posterior fossa presenting the venous ischemia and the pathophysiology and the clinical characteristics of DAVM presenting the venous ischemia are discussed. Associated with occlusive changes in the venous sinuses, DAVM in the posterior fossa develops the venous hypertension of the straight sinus and the venous ischemia of cerebral white matter and basal ganglia. The venous ischemia presents progressive symptoms consisting of dementia with or without the ensuing consciousness disturbance. Multiple parenchymal lesions and abnormally dilated and tortuous veins are the characteristic findings in MRI/CT.

Brain Ischemia↗

PubMed1997

[Quantitative evaluation of diabetic gastrointestinal paresis by measuring transit time of the stomach and the digestive canal].

Our subjects comprised eighty six diabetes mellitus (DM) patients without severe complication. To evaluate gastrointestinal motility quantitatively, we measured gastric emptying time by acetaminophen (APAP) method using serum APAP value and oro-cecal transit time (OCTT) by lactulose hydrogen breath test in the subjects and normal controls (NC). Comparing DM patients and NC, mean APAP value was lower and mean OCTT was prolonged in the former. Analysing DM patients' background, patients with peripheral neuropathy had prolonged OCTT than patients without neuropathy did. Comparing patients with higher HbA1c levels and patients with normal HbA1c levels, mean APAP value, which was closer to normal levels, was higher in the former. Analysing symptoms, some of them were apparently related to abnormal gastrointestinal motility. From these results, it was concluded that measuring both gastric emptying and OCTT was a useful method to evaluate slight abnormal motility in DM patients.

Diabetes Mellitus↗

PubMed1996

MR findings and neurologic manifestations in Lowe oculocerebrorenal syndrome.

Two patients with oculocerebrorenal syndrome are described. Both had abnormal findings on electroencephalography and developed seizure episodes. Although Patient 2 manifested abnormal electroencephalographic findings at the age of 6 years, he did not develop seizures until the age of 9 years. Phenytoin was effective for controlling seizures in both patients. On magnetic resonance examination, there were two different types of lesions. The first lesion manifested high intensity on both T2- and proton density-weighted images, suggesting gliosis or demyelination. The second lesion manifested definitely low signals on both T1- and proton density-weighted images, implying a cystic lesion. However, these lesions on magnetic resonance examination were not correlated with the severity of clinical manifestations.

Adolescent↗

PubMed1996

Clinical grading and outcome after early surgery in aneurysmal subarachnoid hemorrhage.

OBJECTIVE: We propose a modification to the currently prevailing grading systems in patients with subarachnoid hemorrhage. The changes will make them correlate more strongly with the surgical results. METHODS: The relationship between preoperative clinical grades and management outcome was retrospectively investigated in a series of 304 patients with ruptured cerebral aneurysms on the anterior circle of Willis. Preoperatively, every patient was evaluated with the Hunt and Kosnik grading system, the World Federation of Neurological Surgeons Scale, and the Glasgow Coma Scale. All the patients underwent surgical treatment on the aneurysms within 72 hours of the first onset of symptoms. Hyperdynamic therapy was performed after the surgery was evaluated with the Glasgow Outcome Scale. RESULTS: In the Hunt and Kosnik system, the outcome was significantly different between the patients with Grades II and III and those with Grades III and IV, but there was no significant difference among the adjacent grades except between patients with Glasgow Coma Scale scores of 13 and 14. The outcome of oriented patients was significantly better than that of confused patients. Neither eye opening nor presence of focal deficit was a significant prognostic factor. CONCLUSION: To grade patients with subarachnoid hemorrhage objectively, three responses should be recorded separately in the Glasgow Coma Scale score. Patients with confused verbal responses should be graded lower than those who are oriented, even when they have the same total score.

Adult↗

PubMed1996

Amelioration of hyperglycemia in streptozotocin-induced diabetic rats receiving a marginal mass of islet grafts by troglitazone, an oral antidiabetic agent.

Troglitazone, a novel oral antidiabetic agent, was evaluated to determine whether it could have hypoglycemic effects in streptozotocin (STZ)-induced diabetic rats when a marginal mass of islets was transplanted and hyperglycemia persisted after transplantation. Lewis rats (RT1(1)) were used as both donors and recipients. Five hundred fresh islets were transplanted beneath the kidney capsule of STZ-induced diabetic recipients. Troglitazone was administered orally (0.34 mmol/kg/day) for 7 days before and for 60 days after islet transplantation. Neither troglitazone treatment without islet transplantation (n = 8) nor islet transplantation alone (n = 7) could produce normoglycemia (< 11 mmol/L) in diabetic recipients by 60 days after transplantation. In marked contrast, seven of 10 rats receiving islet grafts and treated with troglitazone became normoglycemia at 26.9 +/- 16.4 days (mean +/- SD; n = 7) after transplantation. Removal of the kidney bearing the grafts promptly resulted in the normoglycemic recipients (n = 4) becoming diabetic again. Light and electron microscopically, the intact islets with well-granulated beta cells could be observed in the transplant site of the normoglycemic recipients. These findings clearly demonstrate that the hyperglycemia in STZ-induced diabetic rats receiving an insufficient number of islet grafts to reverse diabetes was ameliorated by troglitazone treatment.

Animals↗

PubMed1996

Partial deletion of the long arm of chromosome 11: ten Japanese children.

The clinical features of partial deletion 11q were correlated with the size of the deleted region. Ten Japanese children with partial deletion of 11q were investigated. They were divided into three groups. Three patients in the first group had interstitial deletions and preserved subband q24.1. Six patients in the second group demonstrated terminal deletion of 11q including subband q24.1, with typical features of 11q- syndrome (Jacobsen syndrome). The third group included only one patient, who had terminal deletion of 11q without characteristics of typical 11q- syndrome. Prominent features of patients in the first group included severe mental and motor developmental delay, seizures, cleft lip and palate, and ophthalmological findings. Patients in the second group showed mild to moderate developmental delays without deterioration. Abnormalities in neuroimages, high intensity in the cerebral white matter in T2-weighted magnetic resonance (MR) images, and recurrent infections were not observed after the age of 7 years. The subject in the third group, with the smallest amount of deleted chromosome, did not show developmental delays, suggesting that some unknown genes related to developmental delays may be located adjacent to subband q24.1. Variation in the deleted parts of 11q resulted in different clinical features in each group.

Abnormalities, Multiple↗

PubMed1996

[Anatomical aspects of posterior fossa affecting lateral suboccipital approach: evaluation by bone-window CT].

Analyzing the bone-window CT of the posterior fossa, the authors investigated three anatomical aspects of the posterior fossa affecting the lateral suboccipital approach (LSA). The high-resolution 1.5 mm-slice bone-window CT images of the posterior fossa in 40 patients with the cerebellopontine angle tumor were reviewed regarding three anatomical aspects: 1) the internal occipital crest (IOC), 2) the posterior surface of the petrous bone, and 3) the "petrous angle". The IOC was sometimes prominent and protruded profoundly into the posterior fossa. The height of IOC from the inner table of the occipital bone was 9.6 +/- 3.3mm (max : 17 mm, min : 3mm). The posterior surface of the petrous bone was convex to the posterior fossa in the most cases; the zenith of the prominence was the porus acusticus. The convexity of the posterior surface in the CT image was objectively evaluated by the "porus angle" made by two lines of A and B; the line A was the posterior half of the posterior surface of the petrous bone, and the line B was the anterior half of it. The "porus angle" in 40 cases was 28 +/- 14 degrees (max : 61 degrees, min : 0 degrees) in the left side, and 28 +/- 12 degrees (max : 56 degrees, min : 0 degrees) in the right side. The "petrous angle", made by the cranial sagittal line and (the posterior half of) the posterior surface of the petrous bone, was 61.8 +/- 5.8 degrees (max : 75 degrees, min : 47 degrees) in the left side, and 62.7 +/- 7.0 (max : 75 degrees, min : 46 degrees) in the right side. In the patient with a prominent IOC, the LSA with a unilateral suboccipital craniotomy may induce the compression of the cerebellar hemisphere by the brain retractor and the prominent IOC, and develop cerebellar contusion. Such a postoperative cerebellar complication can be avoided by a large suboccipital craniotomy with the resection of the prominent IOC extending contralaterally. The severe convexity of the posterior surface of the petrous bone, i.e. the large "porus angle", makes it difficult to get the view of the petroclival region in the LSA. The larger is the "petrous angle", the less cerebellar compression is necessary for the approach to the cerebellopontine angle by the LSA ; the large "petrous angle" is advantageous to the approach. The three anatomical aspects of the posterior fossa, i.e. the IOC, the posterior surface of the petrous bone ("porus angle"), and the "petrous angle", show a considerable variation among individuals. Since these anatomical aspects affect the difficulty and the postoperative complication of the LSA, it can not be overlooked to evaluate them preoperatively by the bone-window CT and plan the surgical approach.

Adult↗

PubMed1996

[The metabolism of glucose and lipids in patients with liver disease undergoing upper abdominal operation and the influence of the difference of intraoperative fluids].

To clarify the change of glucose and lipids metabolism in patients with liver disease undergoing upper abdominal operation, we examined the serum level of glucose, total ketone body, free fatty acid and l-lactate. At the end of the operation, 1-lactate level increased and total ketone body level elevation was suppressed as the bleeding increased. Also in patients undergoing hepatectomy, total ketone body level elevation was suppressed. From these results, we concluded that gluconeogenesis and utilization of fatty acid in the liver were augmented. These metabolic changes were not different between the group infused with lactated Ringer and the group infused with acetated Ringer.

Abdomen↗

PubMed1995

Differentiation between dysmyelination and demyelination using magnetic resonance diffusional anisotropy.

Using magnetic resonance (MR) diffusion-weighted method, we examined the optic and the trigeminal nerves of jimpy and twitcher mice, considered to be animal models of Pelizaeus-Merzbacher disease, hypomyelination disorder, and Krabbe disease, demyelination disorder, respectively. In jimpy mice, diffusional anisotropy of optic nerve did not show a significant difference compared to age-matched control mice, suggesting that diffusional anisotropy does exist in absence of multiple layers of myelin sheath. In twitcher mice, diffusional anisotropy was attenuated remarkably in the optic and trigeminal nerves. Loss of axonal straightness on longitudinal section confirmed by electron microscopy appeared to be the principal explanation for it. It is further suggested that this MR diffusion-weighted imaging method enables us to differentiate hypomyelination from demyelination in vivo.

Animals↗

PubMed1995

Interaction between valproate formulation and phenytoin concentrations.

Changes in phenytoin concentrations caused by switching valproate formulations with different absorption rates were retrospectively investigated in eleven epileptic patients receiving treatment with both drugs. Total plasma phenytoin concentrations were measured before and after a standard tablet of valproate was replaced by the same dose as a slow-release tablet. The mean plasma phenytoin level rose significantly from 14.4 to 18.7 micrograms.ml-1. Nine of eleven patients had markedly increased phenytoin levels (by 21 to 72%), and two developed toxic symptoms. The results indicate that changing valproate formulations can cause major alterations in the plasma concentration of co-administered phenytoin.

Adolescent↗

PubMed1995

The endocrine pancreas of spontaneously diabetic db/db mice: microangiopathy as revealed by transmission electron microscopy.

Abnormalities in ultrastructures of islet capillaries were detected in db/db mice, with the visual inspection and morphometry of electron micrographs. The observed changes are: (1) capillary scarcity; (2) increase in the mean and diversity of capillary size; (3) pericapillary edema and fibrosis; (4) hypertrophy of the pericyte and abundance therein of actin-like microfilaments; and (5) luminal irregularity. Changes (2), (3) and (4) are conceived to indicate hyperperfusion, capillary hypertension and secondary vascular response. In particular, such pericyte changes were found to be shared by other organs whose capillaries are susceptible to diabetic complications.

Animals↗