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Biomedical subjects

S Nagao

Publications and source records attributed to S Nagao.

At least 145 records · Page 8Linked to original sources
PubMed1996

Interleukin-8 (IL-8) is a major neutrophil chemotaxin from human alveolar macrophages stimulated with staphylococcal enterotoxin A (SEA).

Since Staphylococcus aureus is an important human pathogen, and infection of the lungs is characterized by neutrophil infiltration we studied the role of a staphylococcal toxin, enterotoxin A (SEA) on the synthesis and secretion of IL-8 by human alveolar macrophages. As SEA concentration was increased, the IL-8 accumulation in the macrophage conditioned medium increased. The concentration of mRNA encoding IL-8 was also elevated in the macrophage in response to increases in SEA concentration. Although the monocytic cell line U937 was able to respond to SEA and secrete IL-8, treatment with PMA prior to SEA stimulation increased the IL-8 accumulation around fifty fold indicating that maturation of the undifferentiated cell to a more macrophage-like cell facilitated IL-8 accumulation. Stimulating human alveolar macrophages with high concentrations of SEA caused an increase in IL-1 accumulation. However, when the cells were incubated with SEA in the presence of IL-1 receptor antagonist, there was no decrease in IL-8 accumulation. Addition of a neutralizing anti-IL-8 monoclonal antibody to the culture medium of SEA-stimulated macrophages significantly reduced the neutrophil chemotactic activity of the medium. These studies showed that IL-8 is a major neutrophil chemotaxin from human alveolar macrophages stimulated with SEA.

Blotting, Northern↗
PubMed1996

Transvenous embolization of traumatic carotid cavernous fistula with mechanical detachable coils.

An attempt at transarterial balloon embolization of a traumatic carotid cavernous fistula was made but the carotid artery rent was too small for this approach. The patient was then treated by antegrade embolization through a superior ophthalmic vein using mechanical detachable coils. Successful obliteration of the fistula was achieved with preservation of the carotid artery. Transvenous embolization is an alternative technique to treat patients with traumatic carotid cavernous fistulas, especially when a transarterial approach has failed.

Adult↗
PubMed1996

Arginine vasopressin receptor antagonists for treatment of vasogenic brain edema: an experimental study.

Recent studies indicate that centrally released arginine vasopressin (AVP) facilitates brain water permeability in normal and pathological conditions. The effects of central administration of arginine vasopressin (AVP) receptor antagonists on vasogenic brain edema were studied in rats. V1 or V2 receptor antagonists were stereotactically injected into the lateral ventricle 10 min prior to or 1 h after cold brain injury. The injury resulted in significant increases in the mean water content of the lesion and the contralateral hemispheres by 1.15 and 0.38%, respectively. Twenty-four hours after injury, the brain water and sodium contents, the brain swelling, and plasma osmolality were measured. V1 receptor antagonist of 50 ng significantly decreased the brain water and sodium contents and the brain swelling in the adjacent cortex of the lesion without changes in serum osmolality. On the other hand, 5 ng of V1 receptor antagonist and V2 receptor antagonist had no effect on edema. The V1 receptor of AVP is thought to act predominantly on water permeability of the brain. Peptide therapy may become an additional tool for brain edema treatment.

Animals↗
PubMed1996

Clinicopathologic characteristics of polymyositis patients with numerous tissue eosinophils.

INTRODUCTION: We evaluated associated clinicopathologic features of polymyositis (PM) patients with numerous tissue eosinophils. MATERIALS AND METHODS: 680 muscle biopsies were examined in our institution and eight were identified with greater than 0.3 eosinophils per square millimeter in the inflammatory infiltrate without concomitant peripheral eosinophilia. RESULTS: All eight patients had typical PM, but neither dermatomyositis nor inclusion body myositis was identified. Clinically, a large number of PM patients with eosinophils manifested an acute- or subacute-onset of symptoms, myoglobinuria, a marked elevation of serum creatine kinase, a good response to steroid therapy, and a relatively benign course compared with 26 PM patients without eosinophils. Muscle biopsies demonstrated necrotic fibers more frequently in PM patients with eosinophils than in PM patients without eosinophils. Hypertrophic fibers, fiber splitting, basophilic fibers, and lobulated fibers were less frequently observed in PM patients with eosinophils. CONCLUSION: These results suggest that the majority of PM patients with eosinophils may be steroid-responsive and suffer an acute or subacute onset of PM.

Adult↗
PubMed1996

Cerebral vasospastic vessels: histologic changes after percutaneous transluminal angioplasty.

PURPOSE: To investigate histologic changes before and after percutaneous transluminal angioplasty (PTA) in experimental cerebral vasospasm in comparison with normal vessels. MATERIALS AND METHODS: In seven monkeys, vasospasm was induced in the subarachnoid space. After 7 days, PTA was performed. Microscopic studies were performed in vasospastic vessels. In two animals, vasospasm was induced but angioplasty was not performed. The controls were two animals without vasospasm who underwent only contralateral angioplasty. RESULTS: Angiography after vasospasm revealed marked narrowing but dilatation after PTA, without changes in distal spastic vessels. Specimens after PTA showed platelets that covered denuded endothelium, stretching, and focal dehiscence of internal elastic lamina and altered myocytes in media. Myocytes were deformed and arranged irregularly. These changes were not uniform. CONCLUSION: The prolonged effect of PTA may be caused by mechanical damage of myocytes and the nonuniformity of histologic changes in vascular walls.

Angioplasty, Balloon↗
PubMed1996

Abuse of smoking methamphetamine mixed with tobacco. V. Plasma metabolites of N-cyanomethylmethamphetamine, a pyrolysis product formed by smoking methamphetamine in tobacco, and the species difference between mouse and rat.

N-Cyanomethylmethamphetamine (CMMA), N-formylmethamphetamine (FMA) and methamphetamine (MA) were given intraperitoneally to mouse and rat in doses of 3 mg/kg. The major metabolites of CMMA, FMA and MA in plasma were determined at short intervals after administration by GC-MS to obtain the area under the concentration-time curve (AUC). Regarding the plasma concentration of FMA after CMMA administration, a definite species difference was observed between mouse and rat. In rats given CMMA, FMA was the major component, followed by MA, amphetamine (AP), CMMA and N-formylamphetamine (FAP). In mice given CMMA, MA was a major component, followed by AP, FMA, CMMA and FAP. However, it was demonstrated that MA is also non-enzymatically produced from CMMA in plasma. Following FMA administration to rats, FMA was the major component in the plasma, showing the largest AUC value of the four metabolites, FMA, FAP, MA and AP. Following FMA administration to mice, MA showed the largest AUC value, followed by FMA, FAP and AP which were present at low levels even 5 min after injection and were scarcely detectable at 60 min. These results suggest two main mechanisms involved in the metabolism of the N-cyanomethyl group, one of which is the formation of MA by elimination of cyanoformaldehyde from N-alpha-hydroxylated CMMA and the other which is the formation of FMA by elimination of hydrogen cyanide from N-alpha-hydroxylated CMMA. The formation of FMA from CMMA was the predominant pathway in rats but not in mice.

Amphetamines↗
PubMed1996

Indonesian Medicinal Plants. XIV. Characterization of 3'-O-Caffeoylsweroside, a new secoiridoid glucoside, and kelampayosides A and B, two new phenolic apioglucosides, from the bark of Anthocephalus chinensis (Rubiaceae).

A new secoiridoid glucoside named 3'-O-caffeoylsweroside (1), and two new phenolic apioglucosides, named kelampayoside A (4) and kelampayoside B (6), together with eleven known compounds (five iridoids and six alkaloids), were isolated from the bark of Anthocephalus chinensis (Rubiaceae), an Indonesian medicinal plant from Sumatra Island, Indonesia. The chemical structures of 1, 4 and 6 have been elucidated respectively as 3'-O-caffeoylsweroside (1), antiarol 1-O-beta-D-apiofuranosyl (1 --> 6)-beta-D-glucopyranoside (4), and antiarol 1-O-beta-D-5"-O-caffeoylapiofuransoyl (1 --> 6)-beta-D-glucopyranoside (6) on the bases of their chemical and physiochemical properties. Among fourteen constituents characterized, cadambine (13), one of the major indole alkaloid constituents of A. chinensis, was shown to exhibit moderate growth-inhibitory activity against the malarial parasite Plasmodium falciparum (a chloroquine-resistant K1 strain) cultured in human erythrocytes.

Animals↗
PubMed1996

Hemorrhagic pituitary adenoma manifesting as transient global amnesia.

A 68-year-old female presented with recurrent transient global amnesia due to hemorrhagic prolactin-producing pituitary adenoma. Magnetic resonance imaging clearly revealed the anatomical relationship between the hematoma, within the parasellar tumor, and the compressed medial temporal lobe of the right (non-dominant) hemisphere. Within 4 weeks after the start of bromocriptin administration, the adenoma had markedly regressed and the affected temporal lobe was decompressed. She has experienced no further episode of transient global amnesia. Magnetic resonance imaging is recommended to detect latent organic lesions responsible for transient global amnesia, although the disorder is considered to be benign and of functional origin.

Aged↗
PubMed1996

Intramedullary spinal cord and brain metastases from thyroid carcinoma detected 11 years after initial diagnosis--case report.

A 60-year-old male presented with a rare intramedullary spinal cord metastasis from thyroid carcinoma manifesting as rapidly worsening motor and sphincter disturbances. The primary tumor had been treated 11 years previously. Magnetic resonance imaging clearly revealed the hemorrhagic tumor localized in the thoracic spinal cord and an associated, asymptomatic metastasis in the cerebellum. The hypervascular tumors were totally removed. The histological diagnosis was papillary adenocarcinoma. He has been stable for 2 years postoperatively. Surgical resection of intramedullary metastasis should be considered in patients with less malignant tumors such as thyroid carcinoma, especially when accompanied by progressive compression myelopathy.

Brain Neoplasms↗
PubMed1996

[Analysis of proliferating cell nuclear antigen (PCNA) expression in brain tumors].

The expression of PCNA in brain tumor cells was measured in vitro and in situ by using an electrophoretical immunoblotting method and an immunohistochemical staining method. In synchronized C6 rat glioma cells, PCNA were almost parallel to the S phase, although the small amounts of PCNA were expressed in G1 and G2 x M phases. In astrocytic tumors from operative tissues, immunohistochemical PCNA positive rate increased significantly with increasing tumor grade. PCNA positive rate of recurrent meningiomas was also significantly higher than that in nonrecurrent meningiomas. These findings suggest that the PCNA is associated with the cell cycle, especially the S phase and immunohistochemical staining of PCNA is useful to evaluate the proliferating activity of a brain tumor. Immunoblotting method would also be helpful for the exact analysis of proliferating activity in brain tumor cells.

Animals↗
PubMed1996

[Therapeutic effectiveness of combined microsurgery and radiosurgery in a patient with a huge trigeminal neurinoma].

A case of right trigeminal neurinoma extending from the cavernous sinus to the cerebellopontine angle in a 48-year-old male is reported. The patient first noticed right facial numbness in June 1993. Six months later, he experienced headaches with occasional nausea, diplopia, ataxic gait, tinnitus and dysphagia and was referred to our department on January 21, 1994. Neurological examination on admission showed multiple cranial nerve palsy from the 4th to 11th nerve on the right, and the cerebellar sign on the right. Initial CT and MRI revealed a large mass lesion extending from the right cavernous sinus to the right cerebellopontine angle. On February 16, 1994, radical resection of the tumor, except the lesion invading the cavernous sinus, was performed via a combined retroauricular and preauricular transpetrosal transtentorial approach. The histological diagnosis was neurinoma. The patient's postoperative course was uneventful and there was good clinical improvement, although the right facial numbness and mild diplopia persisted. On April 6, 1994, radiosurgery was performed with a maximum dose of 28 Gy and a marginal dose to 14 Gy to the remaining cavernous sinus lesion. Two weeks after radiosurgery, the patient achieved a complete return to his daily routine. Two-year follow-up CT and MRI showed a small residual les on in the right cavernous sinus alone. There was no evidence of tumor growth. No new neurological deficits had developed, and the patient's the double vision had resolved. Thus, the patient has been able to maintain a satisfactory level of activities of daily living. We wound like to emphasize the clinical value of the strategy used to treat this patient which combined microsurgery with subsequent radiosurgery.

Cranial Nerve Neoplasms↗
PubMed1996

[Significance of 5'-deoxy-5-fluorouridine (5'-DFUR) administration before surgery for advanced gastric and colonic cancers--activity of pyrimidine nucleoside phosphorylase (PyNPase) and serum immunosuppressive acidic protein (IAP)].

We administered preoperatively 5'-deoxy-5-fluorouridine (5'-DFUR) for treatment of advanced gastric and colonic cancers, and measured pyrimidine nucleoside phosphorylase (PyNPase) in the excised tumor sample and serum immunosuppressive acidic protein (serum IAP), which is an index of the immunity of host-bearing cancer, while studying its direct antitumor effect and improved immunity. Patients with 24 advanced gastric cancers and 36 colonic cancers were randomly divided into a preoperatively administered group and a non-administered group. In the preoperatively administered group, 5'-DFUR (1,200 mg/day) was orally administered on preoperative days 7 approximately 14. After collecting samples (about 0.5 g) from adjacent normal tissues with tumor within 30 minutes after extirpation of tumor and freezing those less than -20 degrees C, the PyNPase level was measured as soon as possible. Moreever, serum IAP levels at pre-administration in the administered group and on admission in the non-administered group were measured. Those in the administered group were measured again on the operative day. No decreasing tendency of PyNPase was generally found in cases with gastric colonic cancers, and no significant difference in stage-II was not either. However, a decreasing tendency in tumor activity was found by pre-administration. Moreover, there was significant improvement in the serum IAP level in cases with gastric and colonic cancers by pre-operative administration of 5'-DFUR. This tendency was also found in advanced colonic cancer with Dukes-C by Dukes's classification. In conclusion, it was suggested that the pre-operative administration of 5'-DFUR for treatment of advanced gastric and colonic cancers has a favorable influence for prognosis because the tumor region was retarded by the high PyNPase activity according to the severity of tumors and elevating tendency of the immune response in host.

Administration, Oral↗
PubMed1996

[Factors promoting acceptance of death at home].

We have provided home treatment mainly for cancer patients since June 1995 and had 7 such patients until March 1996. Among them two patients died not at home but in the hospital, although the patients and their family understood that the patients were in the terminal stage of illness. It home was thought to be difficult that they accept death at their homes. From the standpoint of physical and mental conditions, social status and actual medical care, the factors to promote death at home were examined. The two cases mentioned above and their families wished to have treatment at home. The reasons why we decided to discontinue medical care at their homes were twofold: 1) the difficulty of palliating patients' symptoms and anxiety; and 2) the uneasiness of the family in caring for patients at home. Therefore sufficient palliation of symptoms and "death education" for patients and families are required to encourage death at home.

Aged↗
PubMed1995

The role of cyclic AMP in the lipopolysaccharide-induced suppression of thymidine kinase activity in macrophage.

We observed that lipopolysaccharide (LPS, 1 micrograms/ml) can suppress [3H]thymidine incorporation into acid-insoluble fraction in a mouse macrophage cell line J774 (over 70% at 6 h) without affecting the uptake of [3H]thymidine or DNA polymerase activity. Paralleling this suppression, a decrease in the thymidine kinase (TK) activity, but not of thymidine monophosphate (TMP) kinase and thymidine diphosphate (TDP) kinase, was observed. LPS dose-dependently increased intracellular cAMP levels to about 3.5-times basal at 6 h, proportionally to the decrease of the TK activity. Elevation of intracellular cAMP by several reagents also decreased TK activity. Apparently LPS treatment elevates cAMP concentration by decreasing the low Km cAMP phosphodiesterase activity (58% at 6 h). The time course of cAMP-dependent protein kinase (PK-A) activity during the first 6 h after LPS treatment correlated with that of cAMP concentration. Treatment with a PK-A inhibitor restored about 63% of LPS-induced reduction of TK activity at 6 h. At longer times, however, there was a discrepancy between the change of cAMP concentration or PK-A activity and the reduction of TK activity. Therefore, protein kinase activation caused by the accumulation of intracellular cAMP probably triggers some mechanism responsible for the reduction of the TK activity.

Cells, Cultured↗
PubMed1995

Genetic mapping of the polycystic kidney gene, pcy, on mouse chromosome 9.

The murine polycystic kidney disease gene, pcy, is an autosomal recessive trait located on chromosome 9. To determine the genetic locus of pcy, 222 intraspecific backcross mice were obtained by mating C57BL/6FG-pcy and Mus molossinus. Restriction fragment length polymorphism analysis of 70 of the 222 backcross progeny showed that pcy, dilute coat color (d), and cholecystokinin (Cck) were located in the order d--pcy--Cck from the centromere. Simple sequence repeat length polymorphism analysis of DNA of all 222 backcross mice was carried out using four markers which were located near the central regions of d and Cck. One and eight recombinations were detected between D9Mit24 and pcy and between D9Mit16 and pcy, respectively. However, no recombinant was observed among pcy, D9Mit14, and D9Mit148. These findings strongly suggest that D9Mit14 and D9Mit148 are located near the pcy gene and are good markers for chromosomal walking to this gene.

Animals↗
PubMed1995

Benign osteoblastoma of the temporal bone: MRI.

We investigated a 27-year-old woman with a retroauricular tumour. MRI revealed a signal void on T1 and T2-weighted images, and irregular enhancement with gadolinium-DTPA. The underlying dura mater also enhanced. The tumour was resected completely, and histological examination showed a benign osteoblastoma.

Adult↗