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Biomedical subjects

K Kosaka

Publications and source records attributed to K Kosaka.

At least 253 records · Page 14Linked to original sources
PubMed1989

An immunohistochemical study of beta-protein in Alzheimer-type dementia brains.

An immunohistochemical study with a polyclonal anti-beta-protein antiserum was performed in order to understand the mechanism of deposition of amyloid fibrils in senile plaques in Alzheimer-type dementia (ATD). Serial cortical sections cut from ATD brains were necessary to investigate the structural correlation between senile plaques and blood vessels. The senile plaques were stained well and a blood vessel or capillary-like structure was found in most of beta-protein-immunoreactive deposits. These findings may suggest an involvement of blood vessels in the formation of at least some of the amyloid deposits in ATD brains.

Alzheimer Disease↗
PubMed1989

Neuropathological study on the nucleus basalis of Meynert in Pick's disease.

The pathological changes in the nucleus basalis of Meynert (nbM) in 10 autopsied cases with Pick's disease were studied in comparison with 15 age-matched controls. Both the number and density of nerve cells and the degree of fibrillary gliosis were examined at the anterior, intermediate, and posterior divisions of the nbM. In only 2 of the 10 Pick cases was the number of neurons significantly reduced, with moderate fibrillary gliosis at the anterior division (case 5: reduced by 64%, case 8: reduced by 46%). This neuronal loss in the anterior nbM division may not be a retrograde degeneration secondary to the cortical lesions, since there were some cases without neuronal loss in the nbM despite the presence of much more severe cortical lesions than in these two cases. In all Pick cases except case 1, mild to moderate fibrillary gliosis was found without an apparent neuronal loss at the posterior division of the nbM. This change in the posterior nbM division may be due to secondary retrograde degeneration, since there was a parallel relationship between the degree of fibrillary gliosis in the posterior nbM division and the severity of cortical lesions in the temporal tip and the superior temporal gyrus, to which the cholinergic fibers are known to project from the posterior division of the nbM. The present study suggests that the mild degeneration of the nbM in most cases with Pick's disease may be secondary, but that there are also some cases of Pick's disease with a primary degeneration in the nbM.

Aged↗
PubMed1989

Distribution and morphology of brain stem plaques in Alzheimer's disease.

The morphology, incidence and distribution of senile plaques in the brain stem were examined in 15 cases of Alzheimer's disease, using mainly the Methenamine-Bodian method. The plaques were found in all cases and were grouped into three types according to their morphology. They were not randomly scattered in the brain stem, but had a distribution common to all cases. There were numerous plaques in the periaqueductal gray, superior colliculus, fourth-ventricle floor and superior central nucleus. The plaques were also found less abundantly in the reticular formation, substantia nigra, pontine nucleus and inferior olivary nucleus. There was a tendency for certain plaque types to be associated with specific regions. In the familial cases, the plaques tended to occur even in the regions where they were rare in other cases. The capillaries with plaque-like degeneration were observed not infrequently in the brain stem. The distribution of plaques did not always coincide with that of neurofibrillary tangles.

Aged↗
PubMed1989

Senile plaque-like structures: observation of a probably unknown type of senile plaque by periodic-acid methenamine silver (PAM) electron microscopy.

Numerous diffuse senile plaque-like structures (SPLSs) were found in the cerebral cortex from cases with dementia of the Alzheimer type by means of the methenamine-Bodian method. SPLSs varied in shape and size. They were never recognized in the original Bodian, PAS and Congo red preparations, but were positive with anti-beta-protein immunostaining and periodic-acid methenamine silver (PAM) methods, which are thought to specifically stain amyloid substance. With PAM electron microscopy, we found sparse aggregations of amorphous, often ramified, structures with fine granular silver deposits in SPLS. Routine electron microscopic examination on the same portion where SPLS were confirmed by PAM electron microscopy revealed amorphous, partially fibrous structures. These structures might be amyloid or amyloid-precursor substance. In SPLSs only a few degenerated neurites and astrocytic processes with glycogen granules were seen. We consider SPLSs to be a kind of senile plaque.

Adult↗
PubMed1989

Pancreatic-type hyperamylasemia in end-stage renal disease.

Pancreatic-type isoamylase (P-type) and salivary-type isoamylase (S-type) activities were determined by the wheat protein inhibitor method in 29 patients with end-stage renal disease and in 38 healthy volunteers. Serum levels of total amylase (322 +/- 43 units/liter) and P-type (212 +/- 39 units/liter) in ESRD were significantly higher than those of controls (total: 142 +/- 7 units/liter, P less than 0.01; P-type: 52 +/- 4 units/liter, P less than 0.01). There was no significant difference between S-type activities in ESRD (110 +/- 16 units/liter) and in controls (90 +/- 6 units/liter). The ratios of amylase clearance to creatinine clearance (Cam/Ccr) and S-type clearance to creatinine clearance (Cs-amy/Ccr) rose significantly in ESRD(Cam/Ccr: 5.7 +/- 0.6%; Cs-amy/Ccr: 4.3 +/- 0.55%) compared to controls (Cam/Ccr: 3.2 +/- 0.24%, P less than 0.01; Cs-amy/Ccr: 2.1 +/- 0.17%, P less than 0.01). The ratio of P-type clearance to creatinine clearance (Cp-amy/Ccr) revealed no significant difference between ESRD (5.5 +/- 0.54%) and controls (5.6 +/- 0.42%). The renal excretion of P-type appeared to be more impaired than that of S-type in ESRD.

Adult↗
PubMed1989

Localized lipodystrophy with panniculitis: light and electron microscopic studies.

A 41-year-old woman with localized lipodystrophy histologically showed lymphohistiocytic inflammation within adipose tissue at the periphery and loss of adipose tissue in the center of the lesion. Ultrastructurally, various degrees of lipophagocytosis by macrophages and giant cells were seen, starting with the projection of cytoplasmic processes into the fat droplet and engulfing pieces of the fat droplet which finally were digested. Laboratory investigations revealed a high serum gamma-globulin level and a positive antinuclear antibody, suggestive of a connective tissue disease or autoimmune disease.

Adipose Tissue↗
PubMed1989

Maleness as risk factor for slowly progressive IDDM.

The effect of sex on longitudinal changes in serum C-peptide immunoreactivity (CPR) response to the oral glucose tolerance test (OGTT) was examined up to 48 mo in 30 islet cell antibody-positive (ICA+), non-insulin-dependent diabetes mellitus (NIDDM) subjects (15 men, 15 women) who were matched for age, duration of diabetes, and mode of treatment. The subjects were recruited from 2858 NIDDM patients screened for ICA between 1980 and 1984. In male NIDDM subjects, CPR levels to OGTT decreased insidiously, and 8 of 15 men developed the insulin-dependent state with abolished CPR. Only 2 female NIDDM subjects progressed to the insulin-dependent state (P less than .05, women vs. men). Thus, CPR in female subjects tended to decrease less than in male subjects. There were no significant differences between the two groups in human leukocyte antigens (HLA) or titer of ICA during the follow-up period. These results suggest that maleness is a major risk factor for slowly progressive beta-cell dysfunction in adult-onset insulin-dependent diabetes mellitus (IDDM).

Adult↗
PubMed1989

[A case of complete rupture of the righ TMJ disc].

A case of complete rupture of the right TMJ disc was described. A 43 year old woman visited our hospital with the chief complaint of a mild pain in the right TMJ. Initially, a conservative treatment using the occlusal splint (condylar repositioning appliance) was carried out. This was because she had reciprocal clicking of the right TMJ which had occurred not long before and it seemed that the symptoms were due to the trouble with the disc. In spite of this treatment, for 6 months no improvement was obtained and the reciprocal clicking changed into crepitation. Moreover the double contrast arthrotomographic image indicated a perforation or a wide rupture of the disc, and deformities of the articular bone. Then a right TMJ osteoarthrosis with wide (complete) disc rupture was diagnosed, and a discectomy was performed. The symptoms were greatly reduced by this treatment. It was conceivable that the steroid which she had used for a long time to treat bronchial asthma caused a remarkable inhibition of the tissue repairing, and an internal derangement of the TMJ rapidly progressed to osteoarthrosis.

Adrenal Cortex Hormones↗
PubMed1989

[An autopsy case of panencephalopathic type of Creutzfeldt-Jakob disease: an early clinical sign documented by magnetic resonance imaging].

We reported an autopsy case of panencephalopathic type of Creutzfeldt-Jakob disease (CJD), one of whose early clinical signs, visual loss, had been documented by magnetic resonance imaging (MRI). The patient was a 59-year-old woman, who showed disturbance of visual acuity, memory and calculation at the early stage. About 2 months later she developed apallic syndrome and revealed myoclonic jerks in her eye balls, face, neck and extremities. Electroencephalography showed periodic synchronous discharge. Three months later after her first symptoms MR showed bilateral occipital atrophy, although we could find no brain atrophy on CT scan. She died of the suffocation caused by bronchopneumonia at the age of 60 years. The total duration of her illness was about 20 months. Neuropathological examination revealed a pronounced diffuse atrophy of the cerebral cortex and white matter. In addition to severe cortical neuronal loss and astrocytosis, spongiform changes were evident. The hippocampus was relatively well preserved. In the cerebral white matter both myelin sheaths and axons disappeared almost completely. The cerebellum showed the severe degeneration of granule cells. These neuropathological findings are consistent with those of panencephalopathic type of CJD. It is important to clarify the abnormalities of MR findings in relation to such early clinical signs of CJD. To the best of our knowledge such reports as ours have not been published previously.

Atrophy↗
PubMed1988

Long-term comparison of oral hypoglycemic agents in diabetic retinopathy. Gliclazide vs. other sulfonylureas.

Gliclazide has been reported to possess the properties of preventing the progression of diabetic retinopathy and of controlling blood glucose levels. This report describes a long-term comparative clinical trial of this agent to assess its efficacy against diabetic retinopathy. One hundred and fifty-nine NIDDM patients with no retinopathy or with simple retinopathy entered this trial. One hundred and nineteen patients receiving other sulfonylurea agents were randomly allocated to two groups (G: gliclazide, SU: other sulfonylureas). Forty patients continued to be treated with diet alone (D group). Finally a total of 60 patients, that is, 21 patients in the G group, 19 patients in the SU group, and 20 patients in the D group, were followed with funduscopic examinations for more than 4 years. The results are summarized as follows. (1) Distribution of background factors between the two drug therapy groups was balanced, but in the D group more male patients and relatively milder cases were involved than in the drug therapy groups. (2) Fasting blood glucose control in the three groups was not significantly different. (3) Funduscopic deterioration was observed less frequently, though not significantly, in the G group than in the other groups. (4) Progression to preproliferative retinopathy was significantly less frequent in the G group than in the SU group. Thus, gliclazide seems to have additional properties compared with other sulfonylurea drugs in preventing deterioration of diabetic retinopathy, and particularly in preventing progression to proliferative retinopathy.

Diabetes Mellitus, Type 2↗
PubMed1988

Profiles of carbohydrate-metabolizing enzymes in human hepatocellular carcinomas and preneoplastic livers.

Activities of key carbohydrate-metabolizing enzymes in biopsied human tissues of hepatocellular carcinoma and related conditions were determined by established methods. Among the enzymes analyzed, fetal-type liver enzymes (low-Km hexokinase, glucose 6-phosphate dehydrogenase, and pyruvate kinase-M2) showed increased activities, and adult-type liver enzymes [glucose 6-phosphatase, fructose 1,6-bisphosphatase, high-Km hexokinase (or glucokinase), and pyruvate kinase-L] showed decreased activities, resulting in undifferentiated enzyme patterns not only in fetal livers and hepatocellular carcinomas but also in livers of acute and chronic hepatitis and liver cirrhosis with or without tumors. Hepatocellular carcinomas showed a general tendency of having greater enzyme deviations than hepatitic and cirrhotic livers. The extent of the enzyme deviation in hepatocellular carcinomas varied considerably from one enzyme to another for each tumor tissue as compared with that in the benign liver diseases. Thus, the phenotypic heterogeneity was important for discriminating between the neoplastic and inflammatory changes in differentiation markers. The enzyme patterns of tumors and their corresponding host cirrhotic livers were unrelated, suggesting that the cirrhotic liver has a significance as preneoplastic state only in terms of having a high incidence of evolving hepatocellular carcinoma.

Carbohydrate Metabolism↗
PubMed1988

Possible coexistence of amino acid (gamma-aminobutyric acid), amine (dopamine) and peptide (substance P); neurons containing immunoreactivities for glutamic acid decarboxylase, tyrosine hydroxylase and substance P in the hamster main olfactory bulb.

The coexistence of immunoreactivities for glutamic acid decarboxylase (GAD), tyrosine hydroxylase (TH) and substance P (SP) was revealed in the hamster main olfactory bulb, using the peroxidase-antiperoxidase immunohistochemical method. Adjacent 40 micron thick Vibratome sections were incubated in different antisera and those cells which were bisected by the plane of sectioning were identified at the paired surfaces of two consecutive sections. The coexistence of the immunoreactivities for 1) TH and GAD, 2) TH and SP and 3) GAD and SP in the same cells could thus be determined by observing the immunoreactivity of the two halves of the cell incubated in two different antisera. About 70% of TH-like immunoreactive (TH-LI) neurons in the periglomerular region also contained GAD-like immunoreactivity, whereas about 45% of GAD-LI ones were also TH-like immunoreactive. Furthermore, almost all (more than 95%) of SP-LI neurons contained both GAD-like and TH-like immunoreactivities. These observations indicate that in the periglomerular region of the hamster main olfactory bulb, some neurons (about 9% of all neurons containing TH-like and/or GAD-like immunoreactivities) may contain three different categories of neuroactive substances, that is, amino acid (GABA), amine (dopamine) and peptide (SP).

Animals↗
PubMed1988

A new resuscitation fluid "stabilized hemoglobin" preparation and characteristics.

A new oxygen carrier for use as a blood substitute was prepared and characterized in vitro. Pyridoxylated hemoglobin, which was obtained by the reaction of human hemoglobin with pyridoxal-5-phosphate, was modified by alpha-carboxymethyl, omega-carboxymethoxyl polyoxyethylene (POE) of the molecular weight 3600 daltons. In order to eliminate viruses and nucleic acids possibly contaminated, the hemoglobin solution was purified by ultrafiltration with a membrane of the nominal molecular weight limit 300 Kdaltons. Furthermore POE conjugated pyridoxylated hemoglobin was treated with 20% ethanol to inactivate viruses. A concentration of hemoglobin, which is incorporated in the conjugate, of the final product was fixed at 6% to make normovolemic exchange transfusion possible. In consideration of the stability during transporting and storage, lyophilized product was selected as a final form ("Stabilized Hemoglobin"). "Stabilized hemoglobin" could be stored in a refrigerator over one year within the acceptable methemoglobin increase. (15%) Viscosity of Stabilized Hemoglobin solution was determined at 2.4 centipoise and is almost half of whole blood and therefore this will be useful not only in resuscitation but also in improvement of microcirculation.

Blood Substitutes↗
PubMed1988

Predictive value of insulin autoantibodies for further progression of beta cell dysfunction in non-insulin-dependent diabetics.

The predictive value of insulin autoantibodies (IAA) was examined prospectively in 58 non-insulin-dependent diabetics (NIDDs) with and without IAA. The longitudinal changes in serum C-peptide (CPR) responses to 100 g oral glucose tolerance tests (OGTTs) as well as IAA and islet cell antibodies (ICA) in these subjects were followed up to 84 mo (mean 38 mo). Based on the positivity for IAA and ICA during the study, the subjects were subdivided into the following four groups; (a) persistently IAA- and ICA-positive subjects (Group 1, n = 7), (b) persistently IAA-negative and ICA-positive subjects (Group 2, n = 18), (c) persistently IAA-positive and ICA-negative subjects (Group 3, n = 3), (d) persistently IAA- and ICA-negative subjects (Group 4, n = 30). In Group 1 subjects serum CPR response to OGTT decreased significantly during the follow-up study (p less than 0.01), while in the remaining three groups, the response did not show any significant change. Blood glucose level during OGTT in Group 1 increased (p less than 0.01), while the values in remaining groups had no significant change. Four out of seven in Group 1 and 3 out of 18 in Group 2 progressed slowly to insulin-dependent state (p less than 0.07 Group 1 vs. Group 2). None of the subjects in Group 3 and Group 4 progressed to insulin-dependent state (p = 0.01 Group 1 vs. Group 4). The percent binding of labeled insulin and titer of ICA did not show any significant change among their positive groups during the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Autoantibodies↗