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Biomedical subjects

S Waga

Publications and source records attributed to S Waga.

At least 127 records · Page 7Linked to original sources
PubMed1989

[Percutaneous transluminal angioplasty of bilateral vertebral arteries: case report].

A 58-year-old female suffered frequent attacks of unconsciousness due to vertebrobasilar insufficiency. She had a slight left hemiparesis, dysarthria, gait disturbance, and decreased vibration sense. Angiography revealed remarkable stenoses of the bilateral vertebral artery origin with inadequate collateral flow from the anterior circulation. Percutaneous transluminal angioplasty (PTA) was performed on the more severely narrowed left vertebral artery through transfemoral approach. This was followed by PTA on the right one through transbrachial approach after an interval of 3 weeks. The procedure cleared off the signs and symptoms; neuroradiological studies including angiography and Xe-CT scan confirmed the improvement. PTA has been performed on stenotic lesions at the origin of the vertebral artery and the common carotid artery with more safety than on stenotic lesions of the other cerebral arteries, because of the smooth luminal non-ulcerated lesions of the former. In spite of the possibility of restenosis after PTA, in selected cases, PTA leads to good results, less complications and shorter stay in hospital. These factors are of major benefit to the patients. In the future, PTA may be an alternative method for treating arterial stenotic lesions in the field of neurosurgery.

Angioplasty, Balloon↗
PubMed1989

[Two types of relaxation responses mediated by cyclic GMP in cerebral arteries].

It has been reported that endothelium-derived relaxing factor (EDRF) possesses chemical and pharmacological properties that are indistinguishable from those of nitric oxide (NO). Moreover, NO is the active chemical species responsible for endothelium-independent vasodilation produced by nitrogen oxide-containing substances including glyceryl trinitrate (GTN). Both EDRF and GTN activate soluble guanylate cyclase and consequently increase cyclic GMP level in various artery preparations. However, there have been few reports regarding cyclic GMP accumulation induced by EDRF or GTN in canine cerebral arteries. Therefore, it was investigated whether EDRF and GTN cause vasodilation through the common pathway mediated by cyclic GMP in the canine basilar artery. The relaxation responses induced by EDRF or GTN were studied in the canine basilar artery by an isometric tension-recording method. EDRF was induced by calcium ionophore A 23187. A 23187 did not relax the vascular tissue in the absence of the endothelial cells. On the other hand, GTN did induce relaxation in either the presence or absence of endothelial cells. FeSO4 at 3 X 10(-5) M reversed A23187-induced relaxation, but not GTN-induced relaxation (N = 10). Since Fe2+ is able to catalyse the formation of O2- in oxygenated phosphate buffer, these findings suggest that Fe2+ antagonizes EDRF by inactivating it via the generation of O2-. By the addition of 10(-5) M methylene blue, both A 23187- and GTN-induced relaxations were reversed (N = 8). Moreover, pretreatment with 10(-5) M methylene blue augmented contractile responses to 3 X 10(-6) M prostaglandin F2 alpha (N = 5).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Primary structure of non-histone protein HMG1 revealed by the nucleotide sequence.

The isolation and sequencing of a cDNA clone coding for the entire sequence of pig thymus non-histone protein HMG1 are described. The sequence analysis reveals a complete 2192-nucleotide sequence with a 5'-terminal untranslated region of 11 nucleotides, 642 nucleotides of an open reading frame that encoded 214 amino acids, and a 3'-terminal untranslated region of 1539 nucleotides. The HMG1 protein, deduced from the nucleotide sequence, has a molecular weight of 24,785 and a C-terminal of a continuous run of 30 acidic amino acids, encoded by a simple repeating sequence of (GAN)30. The predicted amino acid sequence is homologous to HMG1, HMG2, and HMG-T sequences from several sources, suggesting that the protein conformation is under evolutionary constraints. Northern blot analysis reveals that another hybridizable RNA species of smaller size is present. Southern blot analyses suggest that pig genome contains several HMG1 gene equivalents.

Amino Acid Sequence↗
PubMed1988

Nonhistone protein HMG1 removes the transcriptional block caused by left-handed Z-form segment in a supercoiled DNA.

The effect of HMG1 on the transcriptional block caused by left-handed Z-form in a highly negatively supercoiled DNA was examined using a supercoiled plasmid containing a (CG)10 sequence downstream of promoters. The transcription by E. coli RNA polymerase was blocked at the boundary of alternating CG sequence in the Z-form. In the presence of HMG1, RNA polymerase could transcribe through the CG sequence resulting in the chain elongation of transcripts. The addition of HMG1 allowed the stalled RNA polymerase at the CG block to resume transcription. These suggest that HMG1 may remove the Z-block by flipping it back into the B-form.

Animals↗
PubMed1988

Transfrontal intradural microsurgical decompression for traumatic optic nerve injury.

Microsurgical decompression of the optic nerve was performed in 22 patients with traumatic optic nerve injury through a transfrontal intradural approach. When significant improvement is defined as an improvement of the visual acuity of 0.1 or more, 11 patients (50%) showed significant improvement and 7 patients (32%) showed non-significant improvement. Four patients who had been blind preoperatively, did not show any improvement. In cases with a preoperative visual acuity of 0.01 or more, significant improvement was obtained in 80% of the patients, and when the preoperative visual acuity was not nill but less than 0.01, 38% of patients showed significant improvement. We conclude that a transfrontal intradural microsurgical decompression is indicated, when the preoperative visual acuity is 0.01 or more and the time lag is less than 14 days after the injury.

Adolescent↗
PubMed1988

Papilledema and spinal cord tumors.

Two cases of cervical schwannoma associated with papilledema and dementia are described and the pertinent literature is reviewed. It is very important to conduct complete spinal surveys when patients suffer dementia and papilledema and the cerebrospinal fluid protein is elevated.

Aged↗
PubMed1988

Transvenous balloon occlusion of the cavernous sinus: an alternative therapeutic choice for recurrent traumatic carotid-cavernous fistulas.

We report a case of traumatic carotid-cavernous fistula (CCF) that recurred some 9 years after carotid trapping. The recurrent CCF was accompanied by a huge aneurysmal dilatation of the cavernous sinus. Transarterial balloon occlusion of the proximal internal carotid artery failed to occlude the fistula completely because of collateral flow to the fistula. the fistula was completely occluded by a transvenous approach via the jugular vein and inferior petrosal sinus using detachable balloons. The transjugular-inferior petrosal approach to the cavernous sinus can be an alternative for the treatment of traumatic CCF when the transarterial approach has failed to occlude the cavernous sinus.

Adult↗
PubMed1988

Decompression of the vertebral artery for bow-hunter's stroke. Case report.

A case of cerebellar infarction induced by repeated neck rotation ("bow-hunter's stroke") is reported. The most likely mechanism is that repeated rotational neck movement brings about thickening of the atlanto-occipital membrane, fixing the vertebral artery in the vascular groove of the atlas. The vertebral artery is thus pinched at the time of neck rotation, leading to thrombus formation. Embolization results in cerebellar infarction. Surgical decompression of the vertebral artery at the level of the atlas in this case relieved the symptoms, and postoperative angiography demonstrated good flow within the vertebral artery even when the neck was rotated. It was not necessary to restrict the patient's neck movement postoperatively.

Adult↗
PubMed1987

Identification and isolation of soluble histones from bovine milk and serum.

An immunoassay for soluble histones as trace components of biological fluids was developed on the basis of the dual capacity of histones to bind solid-phase DNA and monoclonal anti-histone antibody. Application of this histone-capture assay to bovine milk resulted in a positive signal, and DNA-cellulose chromatography was used to isolate histone-like material in microgram quantities. Western-blot analysis using a panel of anti-histone antibodies demonstrated the presence of histones H2A, H2B and H4 in apparently intact form. DNAase digestion experiments indicated that at least a portion of milk histone was complexed to DNA. Bovine serum was analysed in the same manner on serial DNA-cellulose columns, and H4 and partially degraded H2A were detected by Western-blot analysis. The finding of soluble histones in bovine milk and serum may account for unexpected results when these biological fluids are used as blocking reagents in Western blots and other immunoassays and may have ramifications in the origin and significance of anti-histone antibodies in human disease.

Animals↗
PubMed1987

Successful removal of air gun bullets from the third ventricle.

A patient with air gun bullets in the 3rd ventricle associated with delayed ventricular hemorrhage is presented. Through an anterior transcallosal approach, the surgeon successfully removed the bullets without any significant permanent sequelae.

Cerebral Hemorrhage↗
PubMed1987

Antihistone antibodies in systemic lupus erythematosus.

Antihistone antibodies are prevalent in systemic lupus erythematosus (SLE) and are the predominant autoantibody in patients treated with various drugs. Total histones consist of 5 classes and various histone-histone and DNA-histone complexes. Antibody binding to these various potential antigens has been measured by solid phase and Western blot immunoassays. Relatively unique profiles tend to characterize disease groups, but SLE sera were heterogeneous, displaying reactivity with only 1 to all 5 histones. Antihistone antibodies from human sera as well as murine monoclonal antibodies showed the capacity to react with more than 1 histone class. However, the fine specificities of antihistone antibodies were often assay dependent. Explanations for these discrepancies include degraded and impure histone preparations, irreversible denaturation and the role of soluble histones in biological fluids.

Antibodies, Antinuclear↗
PubMed1986

Hypertensive putaminal hemorrhage: analysis of 182 patients.

The results of treatment for 182 patients with hypertensive putaminal hemorrhage are described. The patients are graded according to the level of consciousness on admission; grade 1, fully conscious; grade 2, somnolent; grade 3, stuporous; grade 4, semicomatose; and grade 5, deeply comatose. Removal of hemorrhage was performed in 44 patients (24%), and conservative treatment was given in 138 patients (76%). One-month mortality in the surgical group was 27%; it was 22% in the conservative group. At 6 months after surgical treatment, the percentages of patients who returned to full-time work or independent life without disability or with minimal disability (good recovery) were 40% in grade 1, 30% in grade 2, 22% in grade 3, 11% in grade 4, and 0% in grade 5; after conservative treatment, percentages with good recovery were 77% in grade 1, 56% in grade 2, 29% in grade 3, 7% in grade 4, and 0% in grade 5. This study shows that surgical treatment does not give better results in the management of hypertensive putaminal hemorrhage.

Activities of Daily Living↗
PubMed1986

Surgical treatment of arteriovenous malformations in the lateral ventricle.

Ten patients with arteriovenous malformation (AVM) predominantly involving the lateral ventricle were operated upon. All the AVM's were not large, less than 2 cm in diameter. Four AVM's were located in the head of the caudate nucleus; 3 were resected through frontal transcortical (transventricular) approach and 1 was excised through anterior transcallosal approach. Two of the former and the latter gave excellent results. Two AVM's located in the temporal horn and trigon in the dominant hemisphere were excised by middle temporal gyrus approach with excellent results. Four AVM's on the dorsal aspect of the thalamus were removed through posterior transcallosal approach with excellent results in 2 and good ones in 1. The brain incision should be as small as possible to enter the lateral ventricle. Position of the patients is also very important. Exposure to excise the AVM's predominantly located in the lateral ventricle is briefly discussed.

Adolescent↗
PubMed1986

Caudate hemorrhage.

Thirteen patients with caudate hemorrhage are described. All the hemorrhages were in the head of the caudate nucleus, and all the hemorrhages but one ruptured in the anterior horn of the lateral ventricle. In 9 patients, the hemorrhage was related to hypertension and the patients were older. In the other 4 patients, the hemorrhage resulted from rupture of an arteriovenous malformation (AVM) and the patients were under 40 years old. Clinical manifestations were nearly the same in both groups, suggestive of subarachnoid hemorrhage and including hemiparesis in most patients. In patients with hypertension, good recovery was obtained by conservative treatment and in those with ruptured AVMs, resection of AVMs through an anterior transcallosal approach may be safe and recommended.

Adult↗