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T Kitamoto

Publications and source records attributed to T Kitamoto.

At least 163 records · Page 9Linked to original sources
PubMed1988

Immunohistochemical confirmation of Creutzfeldt-Jakob disease with a long clinical course with amyloid plaque core antibodies.

Amyloid plaques have been found in the brains of some patients with Creutzfeldt-Jakob disease (CJD) and all patients with Gerstmann-Sträussler syndrome (GSS). We examined paraffin sections from 45 patients with CJD or GSS and from 51 patients with other neurologic diseases, using an antiserum against GSS amyloid plaque cores. The GSS amyloid plaque core antiserum revealed not only birefringent amyloid plaques but also small plaques that cannot be detected by the staining with Congo red dye. Positive immunolabeling was demonstrated in 59% of 34 Japanese patients with CJD, in 100% of 11 patients with GSS, and in none with other neurologic diseases. All cases of CJD of short duration (less than 11 months) were evaluated as being negative, and 95% of 21 long survivors (over 12 months) were positive. This immunohistochemical approach revealed that amyloid plaque is a hallmark of CJD with a long clinical course.

Amyloid↗
PubMed1987

Choroidal epithelial cyst of the cerebral hemisphere. An immunohistochemical study.

A case of choroidal epithelial cyst in the left cerebral hemisphere of a 4-month-old infant is described. The cyst wall was composed of a single epithelial layer with a basement membrane and fibrous connective tissue. An immunohistochemical study revealed the presence of prealbumin in the cytoplasm of these cuboidal epithelial cells. This fact strongly suggested that the cuboidal epithelium lining the cyst wall originated from choroidal epithelial cells. The diagnostic usefulness of the immunohistochemical study in choroidal epithelial cysts is discussed.

Choroid Plexus↗
PubMed1987

Formic acid pretreatment enhances immunostaining of cerebral and systemic amyloids.

The purpose of this study was to design a method by which immunoperoxidase staining can be applied to formalin-fixed, paraffin-embedded tissue sections to demonstrate amyloid deposits in cerebral and systemic amyloidotic tissues. We used anti-prion protein, anti-beta-protein, anti-amyloid A, and anti-prealbumin antisera. The tissue sections were first treated with 100% formic acid for 5, 20, or 60 minutes and the unlabeled immunoperoxidase method (biotin-streptavidin system reagents) was used. This formic acid pretreatment enhanced immunoreactivity of the amyloid deposits which reacted positively with specific antiserum. The specificity of the immunostainings was well preserved. This method can also be used to demonstrate interspecies cross-reactivity, by using anti-human amyloid A and anti-scrapie hamster prion protein antisera, which stained negatively or faintly with amyloid deposits of heterogenous species. The technique is expected to reveal the buried epitopes of amyloid deposits in tissue sections.

Alzheimer Disease↗
PubMed1986

Congophilia in cerebral amyloidosis is modified by inactivation procedures on slow transmissible pathogens.

Cerebral tissues with amyloid deposits were treated by various chemicals which inactivated the agent of subacute spongiform encephalopathy (SSE). We discovered Congophilia in the amyloid plaques in cases of Creutzfeldt-Jakob disease (CJD) and Gerstmann-Sträussler syndrome (GSS) correlated to the chemical inactivation profiles of SSE. After incubation with trichloroacetate, guanidine-SCN, guanidine-HCl, formic acid, phenol and autoclaving, amyloid plaques in unfixed frozen sections of human brains with CJD or GSS, lost the affinity of Congo red and green birefringence under polarized light. In formalin-fixed, paraffin-embedded tissue sections, amyloid plaques of CJD and GSS lost the affinity of Congo red after most of these treatments. On the other hand, senile plaques in the aged, patients with Alzheimer's disease and with senile dementia of the Alzheimer type did not lose the affinity of Congo red after most of these treatments. Therefore, the amyloid deposits in the amyloid plaques differ from those in senile plaques. The methods we used facilitate differentiation of amyloid and senile plaques in formalin-fixed, paraffin-embedded tissues.

Alzheimer Disease↗
PubMed1986

Nonfamilial prealbumin-type amyloid polyneuropathy.

A 53-year-old man with nonfamilial prealbumin-type amyloid polyneuropathy had severe motor, sensory, and autonomic polyneuropathy, beginning at age 48 years. These clinical features closely resembled familial amyloid polyneuropathy (FAP), but abnormal serum prealbumin levels, specific to FAP (Japanese type), were not detected by radioimmunoassay; DNA sequence for prealbumin was normal. Thus, the diagnosis of FAP was excluded. A possible diagnosis of systemic senile amyloidosis was also considered.

Amyloidosis↗
PubMed1986

Amyloid plaques in Creutzfeldt-Jakob disease stain with prion protein antibodies.

Amyloid plaques are found in the brains of some patients with Creutzfeldt-Jakob disease (CJD) and all patients with a related transmissible disorder, Gerstmann-Sträussler syndrome (GSS). In scrapie, a prion disease of animals, amyloid plaques have been shown to be composed of prion proteins (PrP), which form filaments of relatively uniform diameter. We report here that antisera raised against hamster scrapie PrP specifically stain amyloid plaques in the brains of both humans and rodents with CJD as well as a human subject with GSS. Earlier studies showed that these antibodies react with both rodent and human CJD PrP. The immunostained congophilic amyloid plaques in rodent brains measured 10 to 30 micron in diameter and exhibited a Maltese cross appearance. Limited proteolysis enhanced immunostaining of amyloid plaques in human brain sections from patients with CJD or GSS. Presumably proteolysis increases the exposure of those epitopes shared by human and rodent PrP. The differences in immunoreactivity between rodent and human amyloid plaques are consistent with other findings showing that cellular genes, not infectious purified prions, encode PrP.

Amyloid↗
PubMed1986

Scrapie-associated fibrils (SAF) purification method yields amyloid proteins from systemic and cerebral amyloidosis.

We identified fibrils from non-transmissible systemic and cerebral amyloidosis using the purification method of scrapie-associated fibrils (SAF). The fibrils possessed the same nature of congophilia, filamentous structures and molecular weights as amyloid fibrils, and were resistant to Proteinase K digestion. This SAF method makes for a rapid extraction from amyloid-laden tissues. The method, therefore, may purify nontransmissible amyloids alone or together with SAF proteins.

Amyloid↗
PubMed1986

Histochemical classification of systemic amyloid fibril proteins. Alkaline guanidine method.

The alkaline guanidine method facilitates differentiation between different types of amyloid fibril proteins in formaldehyde-fixed, paraffin-embedded tissue sections. Systemic AA-type amyloids lost Congophilia (affinity of Congo red) after incubation with alkaline guanidine for one minute. Systemic AL-type amyloids lost or markedly decreased Congophilia after two hours of treatment with alkaline guanidine. Systemic prealbumin-type amyloids were resistant to incubation for two hours. On the other hand, some cerebral amyloid plaques from patients with Creutzfeldt-Jakob disease and Gerstmann-Sträussler syndrome markedly decreased Congophilia, while in other amyloid plaques, Congophilia was not decreased even with two hours of treatment. The senile plaques from those patients with Alzheimer's disease did not diminish Congophilia after alkaline guanidine treatment. Thus, while this method does not differentiate types of cerebral amyloid protein, it does clearly differentiate types of systemic amyloid fibril proteins.

Adolescent↗
PubMed1986

Novel histochemical approaches to the prealbumin-related senile and familial forms of systemic amyloidosis.

The immunoperoxidase method, the autoclave method, and a newly developed alkaline-guanidine method were used to distinguish senile (SSA) and familial types (FAP) of prealbumin-related amyloidosis in formalin-fixed, paraffin-embedded tissue sections. Because all the amyloid deposits of SSA and FAP reacted positively with the antiprealbumin antiserum, a classification of the amyloid fibril proteins of FAP and SSA by immunohistochemistry, using polyclonal anti-prealbumin antisera, was not feasible. Both the senile and familial forms of amyloidosis showed unchanged Congophilia after prolonged autoclaving. In the alkaline-guanidine method, FAP amyloids were resistant to incubation for 2 hours. On the other hand, amyloid deposits of SSA lost the Congophilia and green birefringence with 2 hours' alkaline-guanidine treatment. Therefore, the autoclave method combined with the alkaline-guanidine method will considerably facilitate differentiation of SSA and FAP, without specific antisera.

Aged↗
PubMed1985

The quaternary structure and activity of newly purified fatty acid synthetase from the Harderian gland of guinea-pig.

Fatty acid synthetase was isolated from the Harderian gland of guinea-pig. The fatty acids synthesized by the purified enzyme were analyzed by mass fragmentography. The purified enzyme had an inherent capacity to utilize methylmalonyl-CoA and synthesize methyl-branched fatty acids. Physicochemical studies indicated that an active enzyme was a dimer, consisted of two subunits of Mr = 2.5 X 10(5). The negatively stained enzyme had an electron micrographic image of an ellipsoidal contour with a continuous middle cleft along the major axis. The major and minor axes were approximately equal to 220 and 150 A, respectively. In a dimer, the subunit had a rod-like structure about 220 A long and 50 A wide. The enzyme was inactivated and dissociated into subunits by incubation at 0 degree C. The inactivated enzyme was fully reactivated by raising the temperature of the solution. The relationship between the quaternary structure of the enzyme and the occurrence of enzymatic activity was studied by high-performance liquid chromatography. Neither active monomers nor inactive dimers were found in inactivation and reactivation processes. The initial velocity of reactivation was proportional to the enzyme concentration over a concentration range of 160-800 micrograms/ml, indicating that the rate-determining step in the reactivation reaction was unimolecular.

Amino Acids↗
PubMed1985

A new method to classify amyloid fibril proteins.

The permanganate method, the immunoperoxidase method, and a newly developed autoclave method were used to distinguish different types of amyloid fibril proteins in formalin-fixed, paraffin-embedded tissue sections. All tissues from permanganate-sensitive cases (AA type) lost the affinity of Congo red and green birefringence under polarized light after incubation with special autoclave treatment. AL type systemic amyloidosis and amyloid plaques of CJD and GSS were permanganate-resistant, but decreased markedly the affinity of Congo red after prolonged autoclaving. On the other hand, prealbumin type systemic amyloidosis and senile plaques of SDAT were resistant to both permanganate oxidation and prolonged autoclaving. Thus, amyloid plaques of CJD and GSS are identical to AL type in systemic amyloidosis, and senile plaques are similar to the prealbumin type. However, anti-prealbumin antiserum did not stain senile plaque amyloid. The anti-human P component stained positively systemic amyloids and cerebral amyloid plaques of SSE, but failed to stain senile plaques of SDAT. Therefore, the amyloid fibril protein of senile plaques is apparently different from other types of amyloid depositions. Amyloid plaques of SSE are different from senile plaques not only with regard to fibril proteins, but also to globular protein in the amyloid.

Adolescent↗
PubMed1983

Alpha-2-macroglobulin-like protease inhibitor from the egg white of cuban crocodile (Crocodylus rhombifer).

A high molecular weight protease inhibitor was purified from the egg white of Cuban crocodile (Crocodylus rhombifer). It inhibited the casein hydrolyzing activity of trypsin, subtilisin and papain. Its native molecular weight was 730,000 and it consisted of four subunits of equal molecular weight, each pair of which were disulfide bonded. The amino acid composition, circular dichroic spectrum and electron micrographs of this protein are also presented. Upon incubation with trypsin this protein yielded a fragment of Mr = 80,000, similar in size to the one known to originate from alpha 2-macroglobulin under the same conditions. The molecular parameters of this protein and the broad inhibitory activity towards thiol and serine proteases with different substrate specificities suggest that it is a protein closely related to alpha 2-macroglobulin in mammalian serum. From its native molecular weight and amino acid composition we believe that this protein is also a reptilian counterpart of the avian ovomacroglobulin described by Miller and Feeney (3).

Alligators and Crocodiles↗