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Biomedical subjects

T Yanagihara

Publications and source records attributed to T Yanagihara.

At least 217 records · Page 12Linked to original sources
PubMed1992

Asymmetric cortical degenerative syndromes: clinical and radiologic correlations.

Eight patients presented with slowly progressive focal neurologic syndromes that conformed to one of three clinically defined categories: progressive nonfluent aphasia (three patients), progressive perceptual-motor impairment (four patients), and progressive frontal lobe syndrome (one patient). Planar MRI and MRI-based surface or volume renderings demonstrated focal areas of atrophy that correlated well with clinical deficits. Single-photon emission computed tomography (SPECT) showed areas of cortical hypoperfusion that corresponded to focally atrophic regions revealed by MRI, but abnormal areas with SPECT were larger than those suggested by MRI. MRI and SPECT are useful in defining the regional structural and functional cerebral abnormalities that underlie slowly progressive focal neurologic syndromes caused by asymmetric cortical degeneration.

Aged↗
PubMed1992

[A case of benign intracranial hypertension with fluctuated symptoms and CSF pressure synchronized with menstrual cycle].

A 39-year-old woman presented with a 2-month history of repeated severe headache, nausea and diplopia. On admission she was obese with bilateral papilledma and abducens weakness. Mass lesion and sinus thrombosis were ruled out by brain CT and angiography. CSF pressure was normal initially. CSF pressure fluctuated with menstrual cycle, sometimes showing over 600 mmH2O with worsening of the symptoms. She was diagnosed as benign intracranial hypertension (BIH). Diuretics did not improve the symptoms, and visual disturbances ensued and deteriorated. A spinal subarachnoid space-peritoneal shunt was inserted to control CSF pressure, showing rapid improvement of headache and diplopia but visual disturbances remained almost unchanged. Optic nerve sheath fenestration was performed without improvement of visual deterioration. We postulated multiple factors such as obesity, menstrual abnormality, iron deficiency anemia and analgesic drugs played important roles to produce BIH in this case. Careful quantitative perimetry should be done to decide a suitable time for surgical treatment in BIH.

Adult↗
PubMed1991

Corrosion properties of soldered joints. Part II: Corrosion pattern of dental solder and dental nickel-chromium alloy.

Six nickel-chromium (Ni-Cr) alloys joined with two solders were evaluated for degree of corrosion after they were immersed in corrosive solution for 100 days. The corroded surface of the Ni-Cr alloy and the cross section of the soldered joint were observed and the solution of nickel and copper (Cu) ions in each combination was measured. No corrosion was observed in the high-resistant Ni-Cr alloys with high Cr content. Pitting corrosion was seen on low-resistant Ni-Cr alloys, which had less Cr content. In the cross section of the joint, the joint of silver solder became porous by corrosion and the corrosion advanced especially along the interface. Solution of Ni ions was detected in all of the combinations of Ni-Cr alloys and solders with exception of the combination of high-resistant Ni-Cr alloys and gold solder. On the other hand, solution of Cu ions was detected in all of the combinations with silver solder.

Chromium↗
PubMed1991

Cerebral angiotropic large cell lymphoma (neoplastic angioendotheliosis): therapeutic considerations.

Cerebral angiotropic large cell lymphoma (neoplastic angioendotheliosis) is a rare disease with a particular propensity to affect the central nervous system by vascular occlusion. Because the disease is rare and there are no specific diagnostic procedures apart from cerebral biopsy, it is difficult to diagnose in life. Accordingly, chemotherapy or radiotherapy has only rarely been attempted and their effectiveness is uncertain. We established the diagnosis in a 62-year-old patient by cerebral biopsy and observed remission following institution of combination chemotherapy. Unfortunately, neurologic deterioration recurred during maintenance chemotherapy. We identified 30 patients in the literature who initially presented with definite central nervous system manifestations and whose clinical conditions were described sufficiently enough for comparison with our case. Eleven patients had the diagnosis made in life, but only 5 received chemotherapy other than corticosteroid hormones. Our patient's survival for 16 months exceeded that in the majority of the 30 reported cases. Intense anti-lymphoma chemotherapy, and possibly radiotherapy, may be beneficial and should be studied in this otherwise rapidly fatal disease. It seems certain that early diagnosis is essential if therapeutic intervention is to be successful.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

A population-based study of migraine headaches in Olmsted County, Minnesota. Case ascertainment and classification.

Using the unique resources of the Rochester Epidemiology Project for population-based studies, we identified 629 Olmsted County, Minn., residents who fulfilled the 1988 International Headache Society criteria for newly diagnosed migraine over a 3-year period. Over 6,400 patient records from several diagnostic rubrics were screened; a substantial proportion of cases had been 'signed-out' to diagnoses other than 'migraine headache'. Medical records were reviewed by two trained nurses who abstracted supporting data for two neurologists. The neurologists determined whether each case met eligibility requirements and assigned a headache diagnosis by consensus. The diagnostic criteria offered some flexibility and were adapted to retrospective record-based research. Most records contained enough information to effectively classify the headache, although information on the frequency and duration of attacks proved to be problematic. A validation re-abstraction of a 10% sample of cases was undertaken with acceptable reproducibility of symptoms and diagnosis. Our study shows that migraine headache can be studied retrospectively through existing detailed medical records.

Headache↗
PubMed1991

Transforming growth factor-alpha, epidermal growth factor receptor, and proliferating potential in benign and malignant gliomas.

Surgical specimens from six benign and 16 malignant human gliomas were investigated immunohistochemically to correlate the degree of malignancy, the distribution of transforming growth factor-alpha (TGF-alpha) and epidermal growth factor (EGF) receptor, and the potential for cell proliferation using monoclonal antibodies to TGF-alpha, EGF receptor, and Ki-67. Fourteen (88%) of the malignant gliomas and one (17%) of the benign gliomas were found to be positive for TGF-alpha, and 14 (88%) of the malignant gliomas and two (33%) of the benign gliomas expressed EGF receptor. The proliferation index with Ki-67 was 18.8% +/- 8.1% (mean +/- standard deviation) in malignant gliomas and 1.9% +/- 1.8% in benign gliomas. In general, cells positive for EGF receptor and Ki-67 were randomly distributed throughout the tumor tissue, and cells positive for TGF-alpha tended to be clustered without obvious relationship to areas of necrosis or blood vessels. In some tumors, cells positive for TGF-alpha, EGF receptor, and Ki-67 were associated in a focal distribution. The more frequent expression of TGF-alpha and EGF receptor in the highly proliferative malignant gliomas is compatible with a role for TGF-alpha and EGF receptor in the induction or stimulation of malignant gliomas.

Astrocytoma↗
PubMed1991

[A case of recurrent cranial neuropathy presenting as recurrent Tolosa-Hunt syndrome].

A 64-year-old woman, with history of hypertension and arteriosclerosis, developed left painful ophthalmoplegia in July, 1988. Neurological examination proved abnormality of the third cranial nerve innervation, otherwise normal. No systemic illness was present. With corticosteroid therapy, the symptoms regressed and completely disappeared in 3 months. In January, 1990, right painful ophthalmoplegia appeared. Neurological examination revealed involvement of right sixth nerve and first branch of the right fifth nerve. With corticosteroid therapy, the symptoms completely regressed in several weeks. In April, 1990, she developed severe pain in the right side of the face. The facial pain disappeared rapidly with corticosteroid therapy, but reappeared following quit of steroid. She complained of severe pain of the right face, the territory of first and second branch of the right fifth nerve, but neurological examination was negative. With corticosteroid therapy, the pain disappeared remaining with mild tingling sensation on the right face, but during the tapering of corticosteroid in August, a severe peripheral type right facial palsy developed. Corticosteroid therapy resumed and the facial palsy regressed almost completely in ten days. Our case suggests that THS might be a variant of so-called recurrent cranial neuropathy.

Aged↗
PubMed1990

Progressive loss of messenger RNA and delayed neuronal death following transient cerebral ischemia in gerbils.

We examined mRNA, cytoplasmic RNA and structural damage in the hippocampus of the gerbil brain after transient ischemia by in situ hybridization, Acridine orange histochemistry and immunohistochemistry. Progressive decline of mRNA became visible in the CA1 region after reperfusion for 3 h and loss of cytoplasmic RNA and emergence of structural damage in 3 days. Reduction of mRNA in the CA3-CA4 region was transient. The findings suggested positive correlation between progressive loss of mRNA and delayed neuronal death.

Animals↗
PubMed1990

Ultrastructural investigation of the CA1 region of the hippocampus after transient cerebral ischemia in gerbils.

Ultrastructural damage leading to delayed neuronal death was investigated in the mid-CA1 region of the hippocampus from the stratum (str.) moleculare to oriens after transient bilateral forebrain ischemia in Mongolian gerbils. After ischemia for 5 min without recirculation, mild swelling of the peripheral part of the apical and basal dendrites was already apparent in the str. moleculare and str. oriens. Mitochondria in the dendrites were also swollen in the same area. During recirculation for 12 h to 3 days, swelling of the dendritic cytoplasm persisted with formation of microvacuoles, but swelling of mitochondria receded. Microvacuolation and loss of microtubules were also observed in the proximal part of the dendrites during this period, and swelling and disruption of internal cristae were observed in mitochondria after recirculation for 3 days. The dendrites became severely degenerated after recirculation for 4 days. In the pyramidal cell bodies, no abnormality was observed at the end of ischemia for 5 min, but disaggregation of polyribosomes and swelling of the endoplasmic reticulum were observed 12 h after recirculation. Proliferation of the endoplasmic reticulum in parallel arrays occurred after recirculation for 1 day and persisted. Severe degeneration of the pyramidal cell bodies was obvious after recirculation for 4 days. The findings observed in the present investigation suggested that the neuronal structure most vulnerable to ischemia was the peripheral part of the dendrites and postischemic neuronal damage occurred early in this part of the dendrites.

Animals↗
PubMed1990

Differential vulnerability of microtubule components in cerebral ischemia.

Differential vulnerability of the major components of microtubules was examined in ischemic gerbil brains by a light microscopic, immunohistochemical method using monoclonal antibodies for microtubule-associated protein (MAP) 1A and MAP2, polyclonal antibody for MAP1 and 2 as well as monoclonal antibody for alpha-tubulin. Progressive cerebral ischemia during unilateral carotid occlusion for 5, 15 and 120 min and reperfusion for 3, 12 and 48 h following bilateral carotid occlusion for 10 min were studied. Ischemic lesions in the subiculum-CA1 region were visualized by all antibodies after ischemia for 5 min but the antibody for alpha-tubulin was less sensitive. The antibody for alpha-tubulin was also less sensitive than antibodies for MAPs for detection of early postischemic lesions. Differential sensitivity was also observed in the cerebral cortex and other brain regions. Microtubules in myelinated axons were more stable than those in dendrites. The observed loss of immunohistochemical reactivities for MAPs and alpha-tubulin may have been caused by activation of calcium-dependent proteolytic enzymes such as calpains. The discrepancy between MAPs and alpha-tubulin could be due to differences in affinities or topographic distributions of these proteins within microtubules.

Animals↗
PubMed1990

Acute transverse myelopathy in multiple sclerosis.

Sixty-two consecutive patients with clinically definite multiple sclerosis (MS) were classified into 2 subgroups: group A, consisting of 16 patients who had shown acute transverse myelopathy (ATM) during the course of illness; and group B, 46 patients without ATM. The clinical features of these 2 groups were analysed prospectively for certain periods, and some significant differences were found. There was (1) later onset, (2) less frequent occurrence of brain stem, cerebellar and cerebral symptoms, (3) more frequent and severe involvement of the optic nerve, (4) a smaller proportion of patients with abnormal findings on brain MRI in group A compared with group B. The clinical features of group B were quite similar to those of previous Western series, while group A seemed to constitute a distinct clinical subgroup in patients with MS.

Adult↗
PubMed1990

Effects of recombinant human erythropoietin on cerebral and cutaneous blood flow and on blood coagulability.

Seizures, hypertensive encephalopathy, transient ischemic attacks, and thrombosis of hemodialysis accesses occurred in early clinical trials with recombinant human erythropoietin. To determine if these events may be caused by the increased hematocrit value or some direct effect of the recombinant human hormone, 10 transfusion-dependent hemodialysis patients were divided into two groups of five according to their serum ferritin concentration: group A. less than 800 microgram/liter, and group B. greater than 800 micrograms/liter. After a month of placebo administration, recombinant human erythropoietin was given (150 U/kg intravenously thrice weekly) for four months and then stopped for one month. Hematocrit values were maintained at 0.33 +/- 0.02 (mean +/- SD) by dose adjustment in group A and at 0.26 +/- 0.02 by thrice weekly phlebotomies in group B, who received a constant dose of erythropoietin. Viscosity increased from subnormal to normal in group A (P less than 0.02) and cerebral blood flow decreased from above normal to normal (P less than 0.02). In group B minor, statistically insignificant, changes in viscosity and reciprocal changes in cerebral blood flow also occurred. There was no change in either group in transcutaneous oxygen tension. Bleeding time decreased toward normal in both groups during recombinant human erythropoietin administration but the changes did not reach statistical significance. Fibrinogen levels were increased in all patients but remained unchanged. No other significant coagulation-related changes were observed. Recombinant erythropoietin in the dosage and schedule of administration described in this study did not lead directly or indirectly to changes likely to precipitate seizures or intravascular thrombosis.

Anemia↗
PubMed1990

Cerebral blood flow and neuronal damage during progressive cerebral ischemia in gerbils.

A combined autoradiographic and immunohistochemical method was used to correlate the extent of focal cerebral ischemia and morphologic ischemic damage following unilateral carotid occlusion in 16 gerbils for 5-30 minutes. Immunohistochemical lesions detectable by the reaction for microtubule-associated proteins 1 and 2 were visible in the subiculum-CA1 and CA2 regions of the hippocampus and layer III/IV of the cerebral cortex after 5 minutes of ischemia (n = 4). Local blood flow was promptly reduced but still heterogeneous after 10 minutes of ischemia (n = 4); local blood flow in immunohistochemical lesions was less than 5 ml/100 g/min except in highly vulnerable regions, where flow values of 5-15 ml/100 g/min were observed. After 15 minutes of ischemia (n = 4) local blood flow in less vulnerable regions including the thalamus and caudoputamen also declined to less than 5 ml/100 g/min, and immunohistochemical lesions became visible in those regions after 30 minutes of ischemia (n = 4). On the other hand, many brain regions tolerated local blood flow of less than 5 ml/100 g/min without ischemic damage. The present study demonstrates that selective tissue vulnerability during progressive cerebral ischemia depends on the degree of hypoperfusion and on factors inherent to neurons in various brain regions.

Animals↗
PubMed1990

[An autopsy case of amyotrophic lateral sclerosis associated with cervical syringomyelia].

An autopsied case of amyotrophic lateral sclerosis complicated by cervical syringomyelia was reported. The case was a 59-year-old man, who first noticed weakness of both lower extremities at 54-year-old. The weakness spread to both upper extremities within 2 years. Cervical myelography revealed multi-level cervical spondylosis and anterior fusion of C5-C7 was done. But the weakness and atrophy of proximal muscle, diminished deep tendon reflex on upper extremities, hyperreflexia and pathological reflexes on both legs, tongue fasciculation and respiratory muscle weakness developed successively, and the patient died of respiratory distress at 59-year-old. Autopsy revealed multiple independent four syrinxes located at the level between C2-C7. One of these syrinxes had ependymal cell lining and thought to be idiopathic syringomyelia. The other three syrinxes were considered to be the cavitation in association with cervical spondylotic myelopathy. Degeneration and decreasing of spinal anterior horn cells, atrophy of medullary pyramis and Bunina bodies were observed as features of typical amyotrophic lateral sclerosis. Cervical spondylosis as causative lesion of multiple syrinxes was discussed, and relationship between ALS and the syrinxes was not indicated clearly.

Amyotrophic Lateral Sclerosis↗
PubMed1989

Brief loss of consciousness in bilateral carotid occlusive disease.

Loss of consciousness is rare in the absence of transient or persistent insult to the diencephalon or mesencephalon. We found three patients with severe atherosclerotic stenosis or occlusion of both internal carotid arteries who experienced brief loss of consciousness. Common characteristics were the absence of clinical or electroencephalographic seizure activities, significant cardiovascular disease, or a history suggestive of vasovagal syncope. Angiographically, the patients had widely patent vertebrobasilar circulation and collaterals from vertebrobasilar to carotid circulation. Episodic loss of consciousness disappeared after carotid endarterectomy. We concluded that bilateral hemispheric ischemia caused brief loss of consciousness, but selective focal ischemia in the subcortical structures superimposed on widespread bihemispheric ischemia may have been responsible. Since loss of consciousness is rare in carotid occlusive diseases, systemic and vertebrobasilar causes must be carefully ruled out in each instance.

Aged↗