Biomedical subjects

M Kagawa

Publications and source records attributed to M Kagawa.

At least 91 records · Page 5Linked to original sources

PubMed1991

The effect of continuous drainage of cerebrospinal fluid in patients with subarachnoid hemorrhage: a retrospective analysis of 108 patients.

The effects of continuous drainage of cerebrospinal fluid (CSF) on vasospasm and hydrocephalus were analyzed retrospectively in 108 patients with subarachnoid hemorrhage (SAH) who were operated on for ruptured aneurysms within 48 hours of their onset. Ninety-two of these patients underwent a procedure for CSF drainage (cisternal drainage, ventricular drainage, lumbar drainage, or a combination of these). The duration, the total volume, and the average daily volume of CSF drainage were 10.4 +/- 7.0 days (mean +/- SD). 2034 +/- 1566 ml, and 190 +/- 65.3 ml, respectively. Patients with a greater drainage volume at a lower height of drainage in the early period after SAH developed more cerebral infarctions later (P less than 0.025). The relationship between the total volume of CSF removed and shunt-dependent hydrocephalus was determined to be statistically significant (P less than 0.005). Cerebral infarction and hydrocephalus after SAH were also found to be statistically associated (P less than 0.001). Thus, continuous cerebrospinal fluid drainage should not be performed too readily in patients with SAH, because the removal of a large amount of CSF can induce cerebral vasospasm as well as hydrocephalus.

Adult↗

PubMed1991

Enhancing potential of 6 different carcinogens on multi-organ tumorigenesis after initial treatment with N-methyl-N-nitrosourea in rats.

The advantages of applying a whole-body concept to the assessment of carcinogenic potential of compounds in a two-stage model after initiation by N-methyl-N-nitrosourea (MNU) were investigated. Male, 6-week-old F344 rats were injected with MNU (20 mg/kg, i.p.) twice a week for 4 weeks and they then received 3,2'-dimethyl-4-aminobiphenyl (DMAB) (50 mg/kg, s.c., once a week), N,N'-dibutylnitrosamine (DBN) (0.05%, in drinking water), N-bis(2-hydroxypropyl)nitrosamine (DHPN) (0.1%, in drinking water), diethylstilbestrol (DES) (2.5 ppm, in diet), sodium o-phenylphenate (S.OPP) (2%, in diet) or captafol (0.15%, in diet) for 20 weeks. All six carcinogens enhanced the incidences of preneoplastic and neoplastic lesions in their respective target organs: liver, pancreas, small intestine and urinary bladder with DMAB; liver, esophagus, forestomach and urinary bladder with DBN; thyroid, lung, liver, esophagus, forestomach, small intestine and urinary bladder with DHPN; liver and forestomach with DES; and thyroid, forestomach, kidney and urinary bladder with S.OPP; liver and forestomach with captafol. The results suggested that prior treatment with MNU sensitized the tissues to the organotropic carcinogenic potential of chemicals given thereafter for as short a period as 20 weeks. Thus, this system could be utilized as a whole-body medium-term bioassay system for the screening of environmental carcinogens, bridging the gap between in vitro mutagenicity and long-term carcinogenicity tests.

Animals↗

PubMed1991

Clinicopathological study of bacterial intracranial aneurysms.

The authors report the clinicopathological findings in six cases of bacterial intracranial aneurysms. All patients received appropriate high-dose antibiotics, and four were treated surgically. One patient with multiple aneurysms of the main trunks died of disseminated intravascular coagulation. Autopsy disclosed no apparent aneurysm or inflammatory cell infiltration, but a partially interrupted internal elastic lamina and thickened intima were disclosed at the angiographical aneurysm sites. These findings suggest that 1) appropriate high-dose antibiotics are effective against inoperable bacterial aneurysms in the main trunks, 2) new aneurysms may be formed in patients with cyanotic congenital heart disease, because bacterial emboli can directly reach the cerebral circulation and reimplant on the fragile arterial walls after vasculitis. Histological examination of aneurysmal walls revealed inflammatory cell infiltration after resolution of clinical endocarditis. This suggests that both appropriate high-dose antibiotic therapy and surgery should be considered in patients with distal bacterial aneurysms.

Adolescent↗

PubMed1991

Colorimetric determination of fructosamine in hemolytic samples for the postmortem diagnosis of diabetes mellitus.

An analytical method of fructosamine (glycated serum protein) determination in hemolytic samples from cadavers was investigated for the postmortem diagnosis of diabetes mellitus. Fructosamine level is usually measured by the reduction of nitroblue tetrazolium (NBT) using a spectrophotometer. This assay was significantly disturbed by more than 1 g/l hemoglobin, which strongly reduced NBT by the catalytic action of the sulfhydryl and glycated groups. Glycated and total hemoglobin levels were then determined simultaneously to exclude the interferences. Total protein concentration was analyzed to eliminate dilutional effects by hemolysis. With these modifications, corrected fructosamine levels in samples containing not more than 10 g/l hemoglobin could be estimated. The assay of such hemolytic samples from 32 cadavers indicated higher fructosamine values in diabetic group than in non-diabetic subjects and the postmortem degradation of the levels as previously reported.

Adolescent↗

PubMed1991

[Clinicopathological studies of three cases of cerebral aneurysms associated with systemic lupus erythematosus].

We report three cases of ruptured cerebral aneurysms associated with systemic lupus erythematosus (SLE). A 52-year-old woman (case 1) with a fifteen-year history of systemic lupus erythematosus suddenly lost consciousness. She was admitted in a state of deep coma. A computed tomography (CT) scan revealed acute hydrocephalus and diffuse subarachnoid hemorrhage in the basal, interhemispheric and bilateral Sylvian cisterns. Fifteen years prior to this admission, cerebral angiograms demonstrated no cerebral aneurysm. She underwent ventricular drainage immediately. Postoperatively, her condition did not improve, and she died on the 18th day. During the autopsy, two saccular cerebral aneurysms were found: one aneurysm was at the right middle cerebral artery bifurcation, and another one was on the anterior communicating artery, which had disruption of the internal elastic lamina and medial smooth muscle, and infiltration of inflammatory cells. In the major cerebral arteries, for example the bilateral internal carotid arteries, disruption or dissection of the internal elastic lamina, intimal fibrosis and transmural infiltration of inflammatory cells were observed. The second patient, a 36-year-old woman with a six-year history of SLE, was admitted to our hospital with sudden severe headache. A CT scan showed subarachnoid hemorrhage, and cerebral angiograms disclosed saccular cerebral aneurysms on the anterior communicating artery and the left superior cerebellar artery, and a fusiform one on the left posterior cerebral artery. Surgery was not recommended because of her multiple medical problems. Her consciousness improved gradually over 2 months. She was transferred to the department of internal medicine for treatment of renal failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

[A case showing the infraoptic course of the anterior cerebral artery associated with anterior cerebral artery aneurysm].

A ruptured anterior cerebral artery aneurysm with anomalous right infraoptic course of the anterior cerebral artery (ACA) was reported. A 40-year old male was admitted because of SAH episode, and computerized tomography (CT) on the day of admission revealed hemorrhage in both Sylvian and interhemispheric fissures. Four-vessel angiography was performed on the same day. A saccular aneurysm was demonstrated in the region of the anterior communicating artery (ACoA), and anomalous artery, which originated from the intradural right carotid artery at the level of the right ophthalmic artery was found to be running medially and superiorly. It supplied the bilateral callosomarginal arteries and the unpaired pericallosal artery. The fenestration of the vertebral artery, duplication of bilateral superior cerebellar arteries, and an occipital artery arising from the right internal carotid artery at the C3 level were found. Surgery was performed on the first day of admission, and the anterior interhemispheric approach was selected. The anomalous branch of the right ICA ran beneath the right optic nerve, ascended between the optic nerves, and supplied the ACoA system. The left hypoplastic A1 segment entered the ACoA. However, the right A1 segment could not be found. The aneurysmal neck, situated between the bilateral callosomarginal arteries and the unpaired pericallosal artery, was clipped with Sugitas curved clip. The postoperative course was uneventful and a follow-up angiograph revealed successful obliteration of the aneurysm.

Adult↗

PubMed1990

A serial study on the development of the temporomandibular joint in the fetal mouse--in particular on the fibrous component in the condylar cartilage.

The development of the temporomandibular joint of 400 fetal mice at stages ranging from the 13th to the 20th day after insemination was investigated under the light, scanning (SEM) and transmission electron (TEM) microscopes. The differentiation and development of a cartilaginous tissue were observed at the supero-posterior end of the mandible at the 13 days after insemination. This tissue grew backward, upward and lateralward continuously and maintained a constant articulation with the squamosal part of the temporal bone. Seventeen days after insemination, cell layers in the condylar process and articular disc were arranged regularly. An supero- and inferno-directional cellular differentiation initiated from the subfibrous (SF) layer toward the articular spaces and cartilaginous layer was observed. The perichondrial ossification had taken place with the invasion of capillaries and the differentiation of osteoblasts in the SF layer, and was followed with a hypertrophic degeneration and endochondral ossification in the condylar process. Such a bi-directional growth of collagen and elastic fibers starting from the SF layer was also observed. Observation under SEM and TEM on the autoclaved condylar process revealed a complicated network consisted of main elastic fibers running in the sagittal direction. These fibers as well as the proteoglycan which contributes to the resilient property of the condylar cartilage and the ability to endure tensile or compressive stress from surrounding tissues during the growth and development of the mandibular condyle. The developing cartilaginous tissue was stimulated with the pressure from the masticatory muscles to initiate an active differentiation of the fibrous layer, which was invaded by the blood capillary system closely related with the subsequent endochondral ossification. These results elucidate that the development of the temporomandibular joint has closely kept relations with the functional influences from surrounding tissues, which also play an important role in regulating postnatal growth of the mandible.

Animals↗

PubMed1990

[Intramedullary hemangiopericytoma of the spinal cord; case report and review of the literature].

Hemangiopericytoma is a rare tumor deriving from capillaries and pericytes. Although it is a well established entity clinically and histologically, its occurrence in the central nervous system adhering to the meninges has been controversial. We described a case of a 39-year-old man with intramedullary hemangiopericytoma. To the best of our knowledge, no previous case of hemangiopericytoma in this location has been reported. We reviewed differential diagnosis of spinal hemangiopericytoma based on neuroradiological points, and clinical findings of the 14 primary cases reported in the literature. The nosological problem of hemangiopericytoma was also discussed.

Adult↗

PubMed1989

Changes in urine composition, bladder epithelial morphology, and DNA synthesis in male F344 rats in response to ingestion of bladder tumor promoters.

An investigation of changes in urine composition, morphology of bladder epithelium, and levels of DNA synthesis following 4 or 8 weeks oral administration of bladder tumor promoters or analogs without promotion potential was performed. The sodium salts of L-ascorbate, o-phenylphenate, and bicarbonate increased the pH value, sodium content, volume, and MgNH4PO4 crystalluria of the urine, while the parent compounds, L-ascorbic acid and o-phenylphenol, which in contrast are not tumor promoters, did not induce these changes. Sodium chloride ingestion caused natriuresis without increasing urinary pH. Diphenyl administration produced only microcalculi consisting of p-phenylphenol. Treatment with the antioxidants butylated hydroxytoluene, butylated hydroxyanisole, and ethoxyquin was also not associated with any changes in urinary pH or Na ions. However, tert-butylhydroquinone did cause an increase in pH. Administration of the strong bladder carcinogens N-butyl-N-(4-hydroxybutyl)nitrosamine and N-ethyl-N-(4-hydroxybutyl)nitrosamine did not result in alteration of urine composition, with the exception of a decrease in phosphorus concentration. However, all the bladder promoters and carcinogens, without exception, brought about an elevation of DNA synthesis in the urothelium and produced morphologic surface alterations such as formation of pleomorphic or short, uniform microvilli and ropy or leafy microridges. Thus, an ability to induce proliferation and cell surface alteration was characteristic of the complete range of bladder promoters investigated. The results suggest that considerable variation in the mechanisms underlying these changes may be involved for different individuals or groups of agents.

Animals↗

PubMed1989

Antagonistic effect of diethylmaleate on the promotion of forestomach carcinogenesis by butylated hydroxyanisole (BHA) in rats pretreated with N-methyl-N'-nitro-N-nitrosoguanidine.

The effects of diethylmaleate (DEM), previously demonstrated to inhibit butylated hydroxyanisole (BHA)-induced forestomach hyperplasia, on BHA promotion of forestomach carcinogenesis in rats pretreated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were examined. Groups of male 6-week-old F344 animals were given a single i.g. administration of 150 mg/kg body weight MNNG and starting 1 week later administered powdered diet containing 1% BHA plus 0.2% DEM, 1% BHA, 0.2% DEM or basal diet alone for 51 weeks. Further groups of rats were treated with 1% BHA plus 0.2% DEM, 1% BHA, 0.2% DEM or basal diet alone without MNNG pretreatment. Histopathological assessment of lesions at week 52 revealed enhancement of MNNG-initiated papilloma (100 versus 50%) and squamous cell carcinoma (100 versus 0%) development by BHA as compared to controls. Additional treatment with DEM, however, significantly reduced the relative incidences of carcinoma in situ (0 versus 35.7%) and squamous cell carcinoma (35.7 versus 100%), as well as BHA-induced forestomach hyperplasia with or without prior MNNG treatment. The results thus clearly demonstrate that DEM acts as a potent antagonist to BHA-promotion of rat forestomach carcinogenesis.

Animals↗

PubMed1989

Strain differences in susceptibility to 2-acetylaminofluorene and phenobarbital promotion of rat hepatocarcinogenesis in a medium-term assay system: quantitation of glutathione S-transferase P-positive foci development.

Strain differences in susceptibility to promotion by the liver carcinogens 2-acetylaminofluorene (2-AAF) and phenobarbital (PB) were examined in the medium-term bioassay system initially developed in our laboratory using male F344 rats as the test animal and glutathione S-transferase placental form (GST-P)-positive foci as the lesion end-point. Numbers and areas per cm2 of induced GST-P-positive hepatocellular foci were compared in LEW, F344, NAR, SD, WBN, SHR, Wistar and ODS rats initiated with diethylnitrosamine (DEN) and subjected to partial hepatectomy during subsequent administration of 2-AAF or PB. LEW, SD, WBN, and F344 rats were most susceptible to hepatopromotion by both compounds, with a hundred fold increase in lesion area being observed for 2-AAF in the LEW case. NAR and SHR strains demonstrated an intermediate response, while Wistar and, in particular, the related ODS rats demonstrated very low susceptibilities. The obvious strain differences could be expressed in terms of comparative indices of promoting effects of 2-AAF and PB as well as DEN itself regarding each of the 8 strains tested. The use of F344 rats for the bioassay model was validated by the relatively high sensitivity to both DEN and 2-AAF initiation as well as second-stage promotion stimulus exhibited.

2-Acetylaminofluorene↗

PubMed1989

Lack of carcinogenicity of quercetin in F344/DuCrj rats.

Quercetin was administered at dietary levels of 0(control), 1.25 and 5.0% to groups of 50 male and 50 female rats for 104 weeks, and then all animals were maintained without quercetin supplement for a further 8 weeks. At 5.0% quercetin, both sexes showed growth retardation throughout the study. There were no treatment-ascribed effects regarding clinical signs, mortality, urinalyses or hematology. Although serum glucose in 5.0% quercetin-treated males was significantly decreased and some relative organ weights in 5.0% groups showed statistically significant increases, these latter changes seemed to be related to the growth retardation. An increased incidence of non-neoplastic hyperplastic polyps in the cecum was noted in the 5.0% males. The incidences of cystic changes and fibroadenomas of the mammary gland, and foci (areas) of hepatocellular alteration in the 5.0% females, and liver bile duct proliferations in the 5.0% males were significantly decreased. No proliferative lesions of the urinary bladder related to treatment with quercetin were found in any rats. The incidences of several other nonneoplastic and neoplastic lesions which demonstrated statistically significant changes appeared to be related to the growth retardation or to be within the normal range, and therefore none was considered to be significant biologically. Thus, the investigation did not demonstrate any clear carcinogenic effect of quercetin on F344 rats at dietary levels of up to 5.0%.

Animals↗

PubMed1989

[An adult case of moyamoya disease associated with marked advance of occlusive lesion in the bilateral carotid system].

We reported an adult case with moyamoya disease in which unilateral obstructive process proceeded to the bilateral lesion during a period of 45 months. A 30-year-old female was admitted to our institute due to frequent ischemic episodes since she was 25 years old. At the time of admission, she was asymptomatic with slightly disturbed psychogenic reactions. At the time of the initial cerebral angiography when she was 25 years old, the right cerebral angiography demonstrated stenosis of the right ICA terminal portion with moyamoya vessels in the basal area and leptomeningeal anastomosis at the right parietal area. The left cerebral angiography revealed normal ICA system with a lightly narrowing Al portion, without Moyamoya vessels. The second cerebral angiography, taken 45 months after the initial angiography, demonstrated progression stenosis of the right ICA terminal portion, with decreasing moyamoya vessels at the basal area, obstruction of the left ICA terminal portion, stenosis at the Al portion with newly developed moyamoya vessels in the left basal area. We concluded at this time that this case was a definite case of moyamoya disease. The third cerebral angiography after right SDP (synangio-dural plasty), 49 months after the initial angiography, revealed, in the right angiography, newly formed anastomotic vessels perfusing the middle cerebral artery region via the extracerebral arteries and in the left cerebral angiography, and an increased obstruction of the ICA terminal portion, transdural anastomosis via the extracerebral arterial system, and a decrease of moyamoya vessels in the basal area. This rare case provided us a good picture of the pathogenic mechanism of moyamoya disease.

Adult↗

PubMed1989

[Stable xenon CT-CBF study with measurement of end-tidal xenon concentration--correction by arterial concentration of xenon].

Non-invasive methods with monitoring end-tidal stable xenon (ETXes) are described for estimating local cerebral blood flow (LCBF) and local partition coefficient (L lambda). 30% of Xes in oxygen was inhaled for 240 sec and exhaled for 160 sec during serial CT scannings after denitrogenation with pure oxygen breathing. During the examination, serial samplings of arterial blood and continuous monitoring of ETXes were performed to determine build up range (A) and build up rate constant (K) of artery. Calculated A and K using the arterial sampling (Aa and Ka, respectively) were compared with the calculated A and K using the continuous monitoring of ETXes (Ae and Ke, respectively) in 109 patients with epilepsy, head trauma, or cerebrovascular diseases. Ae and Ke had significantly positive correlation with Aa and Ka, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Inhalation↗

PubMed1988

Gas chromatographic determination for forensic purposes of petroleum fuel inhaled just before fatal burning.

The determination of petroleum fuel in the blood of burned bodies was carried out by three different gas chromatographic procedures. Seven components of gasoline (isopentane, n-pentane, 2-methylpentane, benzene, 2-methylhexane, 3-methylhexane and toluene) and five of kerosene (xylene, C9H20, mesitylene, pseudocumene and C11H24) were chosen as indicators with a coefficient of variation of 5-24%. The methods were applied to four autopsy cases with a relatively low carboxyhaemoglobin (HbCO) content. When gasoline exposure had occurred, the blood concentrations determined were almost identical whatever the components selected. Great variations in the components determined were found after kerosene exposure, and hydrocarbons greater than or equal to C14 were hardly inhaled by the victims. A higher content of fuel in the left than in the right ventricular blood observed in the autopsy cases suggests fuel inhalation just before death. The same phenomenon was also observed in the content of blood HbCO. Determinations of petroleum fuel and HbCO in both the right and left ventricular blood would be useful for the forensic diagnosis on burned bodies with a low HbCO content.

Aged↗

PubMed1988

Ischemic stroke in infancy, childhood, and adolescence.

The authors studied 34 patients with juvenile ischemic cerebrovascular disease over a 15-year period. Of the 34 patients, 23 had intracranial occlusions attributed to cerebral thrombosis or embolism and 11 had occlusions resulting from moyamoya disease. Clinicopathological features were evaluated in the 23 cases with ischemic stroke, but not those with moyamoya disease. The cause of the arterial occlusion remained undetermined in 11 patients and was found to be an embolism based on congenital heart disease in 8, on trauma in 3, and on infection in 1. Cerebral angiography was performed in 21 patients. Of these, 17 had stenoses or occlusions corresponding to their symptoms. CT scans were performed in 10 patients; the lesion in question showed no stenosis or occlusion with cerebral angiography. With regard to prognosis, patients with unknown etiology had good outcomes compared with those with congenital heart disease. With respect to "acute infantile hemiplegia", 10 patients had convulsive seizures and 4 had a history of an earlier infection. Angiography and CT scans in patients with congenital heart disease demonstrated arterial occlusive sites in the middle cerebral artery region. Three patients had abscesses after their ischemic lesions.

Adolescent↗

PubMed1988

Reciprocal relationship between development of glutathione S-transferase positive liver foci and proliferation of surrounding hepatocytes in rats.

The effects of 2-acetylaminofluorene (2-AAF), phenobarbital (PB) and butylated hydroxyanisole (BHA) on the competitive proliferation of glutathione S-transferase (GST-P) positive liver cell foci induced by diethylnitrosamine (DEN) and surrounding hepatocytes were studied. Rats were given a single i.p. injection of 200 mg/kg body wt of DEN and from 2 weeks later were given a diet containing 0.02% 2-AAF (group 1), 0.05% PB (group 2), 2.0% BHA (group 3), or no supplement (group 4) for 6 weeks. All rats were subjected to partial hepatectomy (PH) at the end of week 3. Animals from each group were killed 1, 2, 3 or 4 days or 1, 2, 3 or 5 weeks after PH. Sequential changes in cellular proliferations after PH were investigated by immunohistochemical staining for GST-P and autoradiography of [3H]thymidine. The development of GST-P positive foci was enhanced strongly by 2-AAF and slightly by PB and was inhibited by BHA. In the group treated with 2-AAF, proliferation of hepatocytes adjacent to foci was almost completely inhibited [labelling index (LI) = 0.4-1.5], but GST-P positive foci cells had a high LI (16.2-26.1) 1 week after PH. In the group treated with PB, proliferation of surrounding hepatocytes was slightly inhibited (LI one day after PH = 16.0) compared with that of control (LI = 24.2), but proliferation of cells in GST-P positive foci was not inhibited (LI one day after PH = 11.3; control value = 11.0). BHA retarded recovery of the LI (LI 4 days after PH = 8.1; control value, 4.0) and did not inhibit proliferation of surrounding hepatocytes. These results indicated an inverse relationship between the development of GST-P positive foci and proliferation of surrounding hepatocytes.

2-Acetylaminofluorene↗

PubMed1988

Enhancing effect of various hepatocarcinogens on induction of preneoplastic glutathione S-transferase placental form positive foci in rats--an approach for a new medium-term bioassay system.

A large series of assays of the hepatocarcinogenic potential of 112 different compounds were carried out using a rapid bioassay system developed in this laboratory based on the two-step concept of hepatocarcinogenesis. Rats were initially given a single dose (200 mg/kg) of diethylnitrosamine (DEN) i.p. and starting 2 weeks later were treated with test compounds for 6 weeks and then killed, all rats being subjected to two-thirds partial hepatectomy (PH) at week 3. Carcinogenic potential was scored by comparing the number and area per cm2 of induced glutathione S-transferase placental form-positive (GST-P+) foci in the liver with those of the corresponding control group given DEN alone. Positive was scored for a significant increase in the value of GST-P+ foci, negative for no change or a decrease. Results were compared to reported Salmonella/microsome and long-term carcinogenicity test findings. Of the liver carcinogens, 10 out of 11 (90.9%) mutagenic, and 11 out of 13 (84.6%) non-mutagenic compounds gave positive results (mean, 87.5%). Carcinogens other than the hepatocarcinogens gave less positive results (two out of 17, 11.8%). None of the compounds reported as non-carcinogenic demonstrated positivity suggesting that the assay system does not suffer from the disadvantage of false-positive results. The protocol system also provided information concerning the inhibitory potential of compounds such as anti-oxidants. It is concluded that the present experimental protocol which requires far fewer animals and shorter duration than a long-term carcinogenicity test has practical applications for the rapid and economical screening of environmental hepatocarcinogens and their inhibitory agents.

Animals↗