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Biomedical subjects

T Miyatake

Publications and source records attributed to T Miyatake.

At least 163 records · Page 9Linked to original sources
PubMed1992

Paraneoplastic cerebellar degeneration: successful early detection and treatment of cancer through characterization of the anti-Purkinje cell antibody.

Paraneoplastic cerebellar degeneration (PCD) is thought to be caused by an autoantibody against both tumor and neuronal tissue. Such autoantibodies are most frequently detected in patients with gynecological or breast cancer, and are designated as anti-Yo. We report here a patient with PCD whose underlying cancer could not be detected despite extensive tumor survey. IgG in her serum and cerebrospinal fluid reacted with the cytoplasm of cerebellar Purkinje cells immunohistochemically. On immunoelectron microscopy, the endoplasmic reticulum and Golgi complex were stained. Her IgG bound to the 58 kD band on immunoblots of cerebellar proteins. A reaction was also observed with the recombinant proteins deduced from the complementary DNA clone encoding a neuronal cell antigen reported by Sakai et al (Ann Neurol 28: 692, 1990). Based on these results, successful early resection of fallopian tube adenocarcinoma was performed. It is crucially important to characterize these PCD related autoantibodies for the early treatment of underlying malignant tumors.

Adenocarcinoma↗
PubMed1992

[Acute relapsing sensory neuropathy following upper respiratory infections--a case report].

A 44-year-old man developed numbness in his hands and feet and an unsteady gait following an upper respiratory symptoms. The symptoms progressed rapidly and reached maximum in a few days, followed by a gradual improvement over a few weeks, but his gait remained unsteady. His symptoms progressively increased over 14 years, with 11 relapses of similar episodes. Neurologic examination showed normal limb strength. Deep tendon reflexes were absent. Touch, cold, and pinprick sensation were impaired in his hands and feet. There was a profound loss of position and vibration sense in all extremities. He demonstrated an unsteady and broad-based gait. Electrophysiologic and histologic examination on the peripheral nerves revealed evidences of axonal degeneration without demyelination involving the sensory nerves.

Acute Disease↗
PubMed1992

[Mutations of amyloid precursor protein in early-onset familial Alzheimer's disease].

Genetic linkage studies of familial Alzheimer's disease (FAD) have suggested that some form of early-onset FAD is linked to proximal long arm of chromosome 21. It has been also suggested that some form of late-onset FAD is linked to long arm of chromosome 19. Goate et al have identified a mis-sense mutation (Val to Ile) in exon 17 of the amyloid precursor protein (APP) gene in 2 of 16 early-onset FAD families, and have shown that the FAD locus in an FAD family is tightly linked to the mis-sense mutation. To determine if the mis-sense mutation is observed in different ethnic origine, we have studied some early-onset FAD families. Two early-onset FAD families showed the existence of the mutation. As the mutation has been identified in different ethnic origine and the mutation has not been observed in normal individuals, it strengthen hypothesis that the mutation is pathogenic. Recently, Val to Phe and Val to Gly mutations have been also identified at the same codon (Codon 717) of the APP gene.

Alzheimer Disease↗
PubMed1992

[Rapid diagnosis of tuberculous meningitis by polymerase chain reaction (PCR)].

Using polymerase chain reaction (PCR), a rapid and highly sensitive method was developed for the diagnosis of tuberculous meningitis. The mycobacterium tuberculosis (M. tuberculosis) genome was detected in CSF of 5 of 6 patients with clinically diagnosed tuberculous meningitis, but not present in CSF from 10 patients with other types of meningitis and 10 normal controls. Furthermore, we detected M. tuberculosis in CSF of 2 of 24 patients with clinically possible tuberculous meningitis. This is highly useful method for the rapid diagnosis of tuberculous meningitis over other conventional method.

Adult↗
PubMed1992

[An acute axonal polyneuropathy affecting intrinsic hand muscles following Campylobacter infection--a case report].

A 24-year-old carpenter had the shakes and fever on March 13, 1990. He suffered from watery diarrhea on March 14 and 15. He left muscle weakness in his thumbs and fingers when he drove nails with a hammer on March 24. The weakness reached maximum by the 3rd day of illness. He was admitted to our hospital on day 4. Neurological examination revealed symmetrical weakness localized in the intrinsic hand muscles (MRC grade 2-4). The deep tendon reflexes were preserved. Sensation was intact except for mild disturbance of superficial sense on both plantar areas. Campylobacter jejuni was cultured from his stool. A complement fixation test indicated serologically preceding C. jejuni infection. Whereas maximum motor nerve conduction velocities were not reduced and distal latencies were not prolonged, compound muscle action potential recorded in the thenar and hypothenar muscles were remarkably reduced on day 5. Needle EMG showed neuropathic changes in four limbs. Sensory nerve conduction velocities and action potentials were normal. The weakness gradually improved in association with increased compound muscle action potentials in the thenar and hypothenar muscles. His muscle symptom fully resolved 2 months after the onset of his illness. Thin-layer chromatogram with immunostaining revealed that serum IgG from this patient reacted with GM1, GD1a, GD1b, but did not react with GM2 and GT1b. Enzyme-linked immunosorbent assay showed that anti-GM1, GD1a, GD1b antibodies titer (IgG) decreased concurrently with the clinical improvement.

Acute Disease↗
PubMed1992

[A case of paraneoplastic cerebellar degeneration--success in early detection of cancer by anti-Purkinje cell antibody].

A 70-year-old woman was admitted to our hospital because of rapidly progressive cerebellar ataxia. Neurological examinations showed saccadic eye movement, downbeat nystagmus, scanning speech, proximal dominant muscle weakness and severe truncal and limb ataxia. Based on these clinical features, she was suspected to have paraneoplastic cerebellar degeneration (PCD), although the malignant tumor was not detected through clinical intensive surveys. Her serum and CSF revealed to have anti-Purkinje cell antibodies immunohistochemically, and western blot analysis showed that they reacted with 58 kd band. In view of previous reports of PCD, she was strongly suspected to have gynecological cancers. The trial laparotomy found early stage fallopian tubal cancer, which had not been detected by CT scan, ultrasonogram and MRI. It is important to detect and characterize these autoantibodies found in the PCD patients for early diagnosis and treatment of underlying cancer.

Aged↗
PubMed1992

[A case of myasthenia gravis complicated by cyclic thrombocytopenia].

A 47-year-old woman with myasthenia gravis for last 11 years was admitted because of relapsed muscle weakness, hypermenorrhea and thrombocytopenia. Physical and neurological examinations revealed diplopia, proximal muscle weakness and purpuras on the left arm and bilateral legs. Repeated hematological examinations revealed cyclic fluctuation of platelet counts which spontaneously changed from the nadir levels of 12-27 x 10(3)/microliters to the peak levels of 150-400 x 10(3)/microliters. The platelet count reached a nadir at the onset of menstruation. Platelet-associated IgG (PAIgG) was within normal level when platelet count was at an increasing phase. Survival time of autologous platelets was normal when platelet count was at an increasing phase. Megakaryocytes in the bone marrow were apparently normal at the nadir phase. The patient's serum obtained at the nadir of platelet count significantly suppressed megakaryocyte colony forming unit (Meg-CFU) formation in comparison with that after the stabilization of platelet count, suggesting that this cyclic thrombocytopenia was secondary to cyclic hypoproduction of megakaryocytes caused by a suppressive factor. On the other hand muscle weakness showed no cyclic fluctuation. Administration of 60 mg/day prednisolone stabilized the platelet count at about 280 x 10(3)/microliters, abolished hypermenorrhea and gradually improved muscle weakness. These findings suggested autoimmune mechanism in the production of a Meg-CFU-suppressive factor might be involved in the pathogenesis of thrombocytopenia.

Female↗
PubMed1991

Immunohistochemical localization of myelin-associated glycoprotein isoforms during the development in the mouse brain.

The developmental changes in localization of myelin-associated glycoprotein (MAG) isoforms in the mouse brain were demonstrated by an immunohistochemical method using antisera specific to two MAG isoforms. The antiserum to the large isoform of MAG (L-MAG) stained the myelin sheaths and the cytoplasm of oligodendroglia in the active myelinating stage in the mouse central nervous system. However, the antiserum to the small isoform of MAG (S-MAG) stained only myelin sheaths in the adult stage. These findings suggest that L-MAG plays an important role in active myelination.

Animals↗
PubMed1991

Expression of the large myelin-associated glycoprotein isoform during the development in the mouse peripheral nervous system.

The developmental maximum expression of the large myelin-associated glycoprotein isoform (L-MAG) protein prior to that of the small myelin-associated glycoprotein isoform (S-MAG) in both the central and peripheral nervous systems (CNS, PNS) in mice was shown by immunoblotting techniques using specific antibodies to the L-MAG protein and the S-MAG protein. Both the L-MAG protein and the S-MAG protein were expressed earlier in the PNS than in the CNS, which reflects earlier myelination in the PNS. The peak of the L-MAG protein concentration was 8 days in the sciatic nerve and 15 days in the brainstem. The concentration of the S-MAG protein in the sciatic nerve reached a peak at 15 days, whereas in the brainstem it increased rapidly between 15 and 20 days and gradually thereafter. Thus, the preceding maximum expression of the L-MAG during active myelination in the PNS demonstrated here as well as in the CNS strongly suggests an important role for L-MAG in myelin formation.

Aging↗
PubMed1991

Quantitation of mitochondrial DNA carrying tRNALys mutation in MERRF patients.

An A to G transition at nucleotide position 8,344 in tRNALys of mitochondrial DNA has been recently identified as a causative mutation of myoclonus epilepsy associated with ragged-red fibers (MERRF). To investigate if the degree of heteroplasmy of mitochondrial DNA is correlated with the severity of MERRF, we have developed a novel method for quantitation of the mutant mitochondrial DNA by polymerase chain reaction using a mismatched primer. With the method, populations of mutant mtDNAs from 5 cases of MERRF carrying the tRNALys mutation were analyzed. The tight linkage of the severity of symptoms and the degree of heteroplasmies is not necessarily observed for all cases, though there is a tendency that patients with less wild type mtDNAs show severer clinical symptoms and earlier onset.

Adolescent↗
PubMed1991

Antibody to a zinc finger protein in a patient with paraneoplastic cerebellar degeneration.

In some patients with paraneoplastic cerebellar degeneration (PCD), autoantibodies against neural components have been identified. Here, we demonstrate a major 58 kd protein antigen in an immunoblot of human cerebellum by serum from a patient with PCD. Immunohistochemically, the serum recognized neural cells especially Purkinje cells in a human brain. To identify the details of the target antigens for the antibody, we isolated a cDNA clone from a human cerebellar library. Homology searches revealed a similarity with the zinc finger proteins. PCD related proteins reported here may be important to maintain neural cells especially those in the cerebellum, and further studies on this molecule may help us elucidate the causes of degenerative or autoimmune diseases in the cerebellum.

Aged↗
PubMed1991

Structure of mouse myelin-associated glycoprotein gene.

The mouse myelin-associated glycoprotein gene was isolated from a mouse gene library. This gene was split into 13 exons distributed about 15 kb in length. Each extracellular immunoglobulin-related domain was encoded by a single exon, and RNA splicing between those exons occurred between the first and second nucleotides of the junctional codon, the features of which are conserved in most of the genes of the immunoglobulin superfamily. The sequence of the 5'-flanking region appeared to have some regions homologous to other myelin proteins, which suggested that they were possible cis-elements for specific expression of oligodendrocytes.

Animals↗
PubMed1991

Human placental sialidase complex: characterization of the 60 kDa protein that cross-reacts with anti-saposin antibodies.

Sialidase isolated from human placenta is associated with several proteins including acid beta-galactosidase, carboxypeptidase, N-acetyl-alpha-galactosaminidase, and others. These proteins are thought to form an aggregated complex during isolation of sialidase. One of the proteins of 60 kDa was recently identified by Potier et al. (Biochem. Biophys. Res. Comm. 173, 449-456, 1990) as a sialidase protein: this protein also cross-reacted with anti-prosaposin antibodies. We have isolated this protein and from the following evidence identified it as a heavy chain component of immunoglobulin G and not sialidase or a derivative of prosaposin. On gel filtration HPLC, sialidase activity and the 60 kDa protein were clearly separated from one another. The 60 kDa protein cross-reacted not only with antibodies raised against human saposins A, C, and D, but also with second antibody (goat anti-rabbit immunoglobulin G antibody) alone. This 60 kDa protein strongly cross-reacted with anti-human immunoglobulin G antibodies. The sequence of the initial 15 amino acids from the N-terminus of the 60 kDa protein was identical to the sequence of an immunoglobulin G heavy chain protein Tie (gamma 1).

Amino Acid Sequence↗