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S Honda

Publications and source records attributed to S Honda.

At least 109 records · Page 6Linked to original sources
PubMed2000

Association between complement regulatory protein factor H and AM34 antigen, detected in senile plaques.

BACKGROUND: We have previously shown that monoclonal antibody AM34, which is reactive with senile plaques, may recognize the C terminus of complement factor H. In this study, we investigated the expression of factor H in tissue from a human brain and the relation between AM34 antigen and factor H. METHOD: Total ribonucleic acid (RNA) was extracted from a normal human brain. A reverse transcriptase-polymerase chain reaction method was employed for detecting messenger RNAs coding for factor H and related proteins. Protein extracts from a normal human brain were also analyzed to detect factor H and related proteins by means of Western blotting. The cerebrospinal fluid from an Alzheimer's disease patient was immunoprecipitated with AM34 and anti-factor-H antibodies, and then it was subjected to gel electrophoresis followed by immunoblotting with AM34 and anti-factor-H antibodies. RESULTS: 26 clones of complementary DNA fragment were obtained by reverse transcriptase-polymerase chain reaction. Among them, seven clones were identical to factor H, and the others were related proteins and unreported sequences. A Western blot analysis of protein extracts from the normal brain tissue exhibited a 150-kd band, indicating the presence of factor H. AM34 was immunoreactive with the 150-kd molecule contained in the immunoprecipitates with anti-factor H antibodies, and vice versa. These results suggest that AM34 antigen could be identical to complement factor H. CONCLUSIONS: The results of our experiments indicate that factor H is possibly detected in the human brain, and that the AM34 antibody could recognize factor H. Because AM34 is capable of staining senile plaques positively, factor H is suggested to be associated with senile plaques in the human brain.

Aged↗
PubMed2000

The rate of cell growth is regulated by purine biosynthesis via ATP production and G(1) to S phase transition.

We recently showed that an increased supply of purine nucleotides increased the growth rate of cultured fibroblasts. To understand the mechanism of the growth rate regulation, CHO K1 (a wild type of Chinese hamster ovary fibroblast cell line) and CHO ade (-)A (a cell line deficient in amidophosphoribosyltransferase, a rate-limiting enzyme of the de novo pathway) were cultured under various conditions. Moreover, a defective de novo pathway in CHO ade (-)A cells was exogenously restored by 5-amino-4-imidazole-carboxamide riboside, a precursor of the de novo pathway. The following parameters were determined: the growth rate of CHO fibroblasts, the metabolic rate of the de novo pathway, the enzyme activities of amidophosphoribosyltransferase and hypoxanthine phosphoribosyltransferase, the content of intracellular nucleotides, and the duration of each cell-cycle phase. We concluded the following: (i) Purine de novo synthesis, rather than purine salvage synthesis or pyrimidine synthesis, limits the growth rate. (ii) Purine nucleotides are synthesized preferentially by the salvage pathway as long as hypoxanthine is available for energy conservation. (iii) The GTP content depends on the intracellular ATP content. (iv) Biosynthesis of purine nucleotides increases the growth rate mainly through ATP production and promotion of the G(1)/S transition.

Adenosine Triphosphate↗
PubMed2000

Preoperative diagnosis of ileal lipoma by endoscopic ultrasonography probe.

The occurrence of tumor in the small intestine is relatively rare. It has been demonstrated that lipoma of the ileum is a cause of intussusception. We report a 59-year-old man admitted to our hospital for lower abdominal pain. Diagnosis of intussusception was made by abdominal x-ray and ultrasonography. Enema contrast studies revealed ileocolic intussusception. Colonoscopy revealed a tumor with an submucosal tumor (SMT)-like head and coil-spring appearance in the ascending colon. Endoscopic ultrasonography (EUS) revealed a hyperechoic submucosal lesion with features compatible with lipoma. Subsequently, this was confirmed histopathologically after resection. To our knowledge, this is the first report of preoperative diagnosis of ileal lipoma by EUS.

Endosonography↗
PubMed2000

Demographic and reproductive factors for high seroprevalence of Chlamydia trachomatis among pregnant women in Japan.

In order to elucidate demographic and reproductive factors associated with Chlamydia trachomatis seropositivity, serological screening and questionnaire survey were conducted on pregnant women in Nagasaki Prefecture, Japan. Serum samples were taken from 1718 pregnant women between September and December, 1996, at the cooperative obstetric hospitals and clinics, and tested for the presence of antibodies to C. trachomatis using the enzyme immunoassay. A questionnaire was administered on a sub-sample (n -409), among whom 85 (20.8%) were seropositive. A multiple logistic analysis revealed that four characteristics showed a significant association with the seropositivity: (i) experience of premarital pregnancy, (ii) non use of condoms, (iii) short duration of education, and (iv) more frequent induced abortion. The unsafe sexual behavior of young people lacking proper knowledge of how to prevent STD is the most important intervention target for control of the C. trachomatis epidemic in Japan.

Abortion, Induced↗
PubMed2000

Homozygous Pro74-->Arg mutation in the platelet glycoprotein Ibbeta gene associated with Bernard-Soulier syndrome.

Bernard-Soulier syndrome (BSS) is an autosomal recessive bleeding disorder due to quantitative or qualitative abnormalities in the glycoprotein (GP) Ib/IX/V complex, the platelet receptor for von Willebrand factor. This complex is composed of four subunits, GPIbalpha, GPIbbeta, GPIX and GPV. We describe here the genetic basis of the disorder in a patient with BSS. Flow cytometric analysis of the patient's platelets showed greatly reduced GPIbalpha and GPIX surface expression. Immunoblot analysis disclosed absence of GPIbalpha, GPIbbeta and GPIX in the platelets. DNA sequencing analysis revealed a novel missense mutation in the GPIbbeta gene that converts Pro (CCG) to Arg (CGG) at residue 74. Homozygosity of the mutation was confirmed by allele-specific restriction analysis, chromosome 22 microsatellite analysis and quantitative Southern blotting. The mutant GPIbbeta was normally transcribed. Transient transfection studies confirmed that mutant GPIbbeta impairs surface expression of GPIb/IX, showing that the mutation is responsible for a BSS phenotype observed in the patient.

Amino Acid Substitution↗
PubMed2000

[Dialogue with schizophrenics statements not derived from inner experiences].

When we examine the psychopathological issues of schizophrenia, we usually try to find clues in patients' statements spoken in dialogic situations. However, if we take into account that schizophrenic changes are supposed to contain various degrees of difficulties in inter-subjectivity, we must discuss first how and to what extent such patients are expressing themselves and communicating to us. The purpose of the present study was to determine the characteristics of dialogues between psychiatrists and schizophrenic patients and to consider the relationship of the communication to the patients' inner experiences. In order to discuss these problems, the authors made a study of 3 schizophrenic patients who had been in highly deteriorated mental states but managed to express themselves. The clinical characteristics of these patients were as follows: 1) First, the patients had been quite at a loss for words and remained silent. However, if the therapist carefully attended them and helped them express their feelings, they began to speak slowly. 2) However, shortly after they had finished expressing something, they often complained that they could not look backward or they did not know anything about what had been expressed even when there were no defects of memory. 3) The patients did not know what their inner experiences were until they had been asked back again and again about their experiences by the therapist. In other words, they could encounter their inner worlds only through the intervention of the therapist. These clinical observations maintain the following interpretations: 1) The patients' expressions did not pass into their own possession and had derivation from their inner experiences. 2) From a phenomenological point of view, this was apparently related to the disunion between 'expressing selves' and 'experienced selves.' 3) Through the therapeutic dialogues, their experiences came up to the inter-subjective dimension, which led them to create their inner experiences.

Adult↗
PubMed2000

Early onset of hemophagocytic syndrome following allogeneic bone marrow transplantation.

We report a 40-year-old man who presented with acute onset of hemophagocytic syndrome (HPS) after allogeneic bone marrow transplantation (alloBMT) for acute myelogenous leukemia. On day 8 after alloBMT, the patient suddenly manifested high-grade fever, transfusion-resistant severe anemia, and thrombocytopenia. Neither veno-occlusive disease nor thrombotic microangiopathy was documented. The level of ferritin in serum was elevated to 1192 ng/mL. A bone marrow aspiration test on day 16 showed a markedly increased number of activated macrophages showing massive hemophagocytosis. Serum levels of interferon-gamma, soluble interleukin-2 receptor, interleukin-6, tumor necrosis factor-alpha, and macrophage colony-stimulating factor (M-CSF) were elevated. From these findings, we determined his transfusion-resistant cytopenias to be attributable to HPS. No viruses (including cytomegalovirus, Epstein-Barr virus, human herpes-virus-6, parvovirus B19, and adenovirus B11) were detected in serum or urine by polymerase chain reaction amplification. We speculate that in addition to the administration of M-CSF, hypercytokinemia during the early phase post-alloBMT might have contributed to the onset of HPS in this patient. Methylprednisolone pulse therapy was very effective for the treatment of the HPS. This case reveals that HPS could develop after alloBMT, even when engraftment of hematopoietic cells is not confirmed.

Adult↗
PubMed2000

[Comparison of reticulated platelet count with plasma glycocalicin concentration as a marker of platelet turnover in patients with thrombocytopenic disorders].

Measurements of plasma glycocalicin (GC) and reticulated platelets (RP) have been reported to be useful for classifying thrombocytopenic disorders. However, there have been no reports comparing the clinical usefulness of the two methods. We measured GC and RP levels simultaneously in 39 patients with idiopathic thrombocytopenic purpura (ITP), 15 patients with aplastic anemia (AA), and 17 patients with hypoplastic thrombocytopenia (HypoT) due to chemotherapy. The GC index (GC level normalized for the individual platelet count) and the percentage of RP (%RP), a parameter of platelet life span, were very high (7.5 +/- 11.4 and 20.8 +/- 13.0%, respectively) in patients with ITP as compared with those of healthy subjects (1.3 +/- 0.5 and 7.9 +/- 2.5%, respectively). However, 6 AA patients and 14 HypoT patients, in whom platelet life span is thought to be normal, also had an elevated GC index, suggestive of a false positive result. The RP, a parameter of platelet production, was low in all AA and HypoT patients except for one in each case. However, the GC level, an additional parameter of platelet production, was normal in 4 AA and 8 HypoT patients, indicating that it is not a sensitive indicator. We conclude that the RP and %RP are more feasible markers of thrombopoiesis and platelet life span, respectively, than the GC level and GC index.

Blood Platelets↗
PubMed2000

[Encephalomyelopathy demonstrated on MRI in a case of chronic toluene intoxication].

Myelopathy in chronic toluene intoxication is rare. We present obvious lesions of the spinal cord on MRI in a 30-year-old Japanese man with chronic toluene intoxication. He had abused toluene for more than 10 years, and developed visual impairment, horizontal nystagmus, pyramidal tract signs, postural tremor, Romberg's sign, and sensory disturbance below the level of Th 2 dermatome. Anti-HTLV-1 antibody titer and vitamin B12 level in the serum were within normal limits. Biochemical analysis showed no increase of very long chain fatty acids. Cerebrospinal fluid showed no abnormal findings. Auditory brainstem response showed delay of I-V interpeak latency. Somatosensory evoked potential with the median nerve stimulation showed delay of N13-N20 central conduction time, which was later followed by absence of N14-N20 components. On MRI in T2 weighted image, marked high intensity was demonstrated in the posterior limbs of the internal capsule, and in the posterior columns and lateral tracts from the cervical through the upper thoracic cord. Cerebral lesions probably reflect demyelination and axonal degeneration produced by chronic toluene abuse. Spinal cord lesions seem to be secondary to nerve fiber changes more proximal to the nerve cell bodies.

Adult↗
PubMed1999

Rat primary cultured microglia express glial cell line-derived neurotrophic factor receptors.

The neurotrophic effect of glial cell line-derived neurotrophic factor (GDNF) has been well documented in both the central and peripheral nervous systems. From the histological findings, target cells of GDNF have been considered to be neurons. In the present study, the expression of GDNF receptors, ret and GFRalpha-1, was demonstrated in rat primary cultured microglia by reverse transcription-polymerase chain reaction and the protein-level expression of Ret was also confirmed by Western-blotting analyses. Moreover, GDNF stimulated the phosphorylation of MAP kinase (ERK1/2) in the cells. These results suggest that GDNF regulates not only neuronal survival and maturation but also certain functions of microglia in the brain.

Animals↗
PubMed1999

A novel NE-dlg/SAP102-associated protein, p51-nedasin, related to the amidohydrolase superfamily, interferes with the association between NE-dlg/SAP102 and N-methyl-D-aspartate receptor.

The membrane-associated guanylate kinase proteins have been known to interact various membrane receptors with their N-terminal segments designated the PDZ domains and to cluster these receptors at the target site of the cell membrane. NE-dlg/SAP102, a neuronal and endocrine tissue-specific MAGUK family protein, was found to be expressed in both dendrites and cell bodies in neuronal cells. Although NE-dlg/SAP102 localized at dendrites was shown to interact with N-methyl-D-aspartate receptor 2B via the PDZ domains to compose postsynaptic density, the binding proteins existing in the cell body of the neuron are still unknown. Here we report the isolation of a novel NE-dlg/SAP102-associated protein, p51-nedasin. Nedasin has a significant homology with amidohydrolase superfamily proteins and shows identical sequences to a recently identified protein that has guanine aminohydrolase activity. Nedasin has four alternative splice variants (S, V1, V2, and V3) that exhibited different C-terminal structures. NE-dlg/SAP102 is shown to interact with only the S form of nedasin which is predominantly expressed in brain. The expression of nedasin in neuronal cells increases in parallel with the progress of synaptogenesis and is mainly detected in cell bodies where it co-localizes with NE-dlg/SAP102. Furthermore, nedasin interferes with the association between NE-dlg/SAP102 and NMDA receptor 2B in vitro. These findings suggest that alternative splicing of nedasin may play a role in the formation and/or structural change in synapses during neuronal development by modifying clustering of neurotransmitter receptors at the synaptic sites.

Adaptor Proteins, Signal Transducing↗
PubMed1999

A GCM motif protein is involved in placenta-specific expression of human aromatase gene.

A new cis-element, trophoblast-specific element 2 (TSE2) is located in the placenta-specific enhancer of the human aromatase gene that dictates its tissue-specific expression. In the minimum enhancer region, an element similar to the trophoblast-specific element (TSE), originally described for the human chorionic gonadotropin alpha-subunit gene, also exists (Yamada, K., Harada, N., Honda, S., and Takagi, Y. (1995) J. Biol. Chem. 270, 25064-25069). The co-presence of TSE and TSE2 is required to direct trophoblast-specific expression driven by a heterologous thymidine kinase promoter. A 2562-base pair cDNA clone encoding a 436-amino acid protein that binds to TSE2 was isolated from a human placental cDNA library using a yeast one-hybrid system with the TSE2 as a reporter sequence. The protein was revealed to be identical to hGCMa, a mammalian homologue of the Drosophila GCM (glia cells missing) protein. Expression of hGCMa is restricted to the placenta. The protein also binds to PLE1 in the leptin promoter among other cis-elements reported to confer placenta-specific expression, suggesting that hGCMa is a placenta-specific transcription regulator, possibly involved in the expression of multiple placenta-specific genes.

Aromatase↗
PubMed1999

Folding energetics of a multidomain protein, flagellin.

Thermodynamic investigations of flagellin from Salmonella typhimurium and its proteolytic fragments were conducted by differential scanning calorimetry (DSC) and circular dichroism (CD) melting measurements. A new method of analysis for a multi-state transition based on our original theoretical treatment of thermodynamic equations has been developed to analyze those data. The analysis of DSC curves confirmed the three thermodynamic domains of flagellin. The thermodynamic parameters of each domain were revised from those previously reported and the new values of the parameters have a good correlation to the apparent molecular masses of the morphological domains. CD melting measurements at far and near-UV wavelengths showed sequential unfolding of the domains. Therefore, we could reasonably assign the thermodynamically identified domains to the morphological domains. Further analysis of both DSC and CD data provided insights into the folding energetics of the multidomain structure of flagellin. An inner domain (Df1) of flagellin in the filament unfolds through a relatively broad transition, while the two outer domains unfold cooperatively and show sharp transitions. This indicates that the interdomain interactions between Df1 and D2 has different characteristics from the apparently more intimate interactions between D2 and D3. These characteristics suggest that flagellin is organized with relatively flexible domains and rigid domains, which appears to be responsible for the well-regulated assembly mechanism of the bacterial flagellar filament.

Calorimetry, Differential Scanning↗
PubMed1999

Regulation by 1alpha,25-dihydroxyvitamin D(3) of expression of stanniocalcin messages in the rat kidney and ovary.

Regulation by vitamin D(3) of expression of the genes for stanniocalcins 1 and 2 (STC-1 and STC-2) was studied and their levels were shown to be oppositely regulated in the kidney and to remain unaffected in the ovary. Female rats were treated with calcitriol, the active form of vitamin D(3), and alterations in the levels of STC-1 and STC-2 mRNA were determined by Northern blot analysis in the kidney and ovary where the STC-1-expressing cells have previously been identified by in situ hybridization histochemistry. In the kidney, calcitriol treatment increased the STC-1 mRNA levels more than 3-fold, but decreased the STC-2 message to trace levels. In the ovary, however, both STC-1 and STC-2 mRNA levels were not significantly affected by the calcitriol treatment. These results support the hypotheses that (1) STC-1 and STC-2 have opposite effects on calcium and phosphate homeostasis, namely anti-hypercalcemic and anti-hypocalcemic actions, respectively, and (2) the mammalian stanniocalcin system acquired, in addition to the role in the systemic mineral metabolism, a role in the reproduction system that operates independently of the systemic condition.

Animals↗
PubMed1999

Therapeutic effect of topical calcium gluconate for hydrofluoric acid burn--time limit for the start of the treatment.

BACKGROUND: There are few studies regarding the time-dependent effectiveness of topical calcium gluconate treatment for the experimental hydrofluoric acid (HF) burn. METHODS: For producing a HF-burn, a drop of 46% or 23% HF solution was put on the back of rats for 3 minutes followed by washing with tap water. Calcium gluconate jelly or ointment was then applied to the burn area at various time intervals. The ointment was applied once a day thereafter. RESULTS: The topical calcium gluconate treatment was much more effective if the application was started within 3 hours. On the other hand, if the application was started after 6 hours or more, there was no difference between the groups and the non-treatment groups. CONCLUSIONS: It is suggested that practitioners should be ready to prepare quickly the calcium gluconate ointment to treat a HF burn, since the calcium gluconate ointment is not commercially available in Japan.

Administration, Topical↗