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Biomedical subjects

H Endo

Publications and source records attributed to H Endo.

At least 199 records · Page 11Linked to original sources
PubMed1998

Monoclonal antibody TSd-1 is specific to elongating and matured spermatids in testis of common tree shrew (Tupaia glis).

The monoclonal antibody (MAb), named TSd-1, specific to spermatogenic cells of the common tree shrew (Tupaia glis) was established and characterized using immunohistochemistry and immunoblotting. MAb TSd-1 reacted with elongating and matured spermatids in a stage-dependent manner. TSd-1 recognized a 94 kilodalton (kDa) peptide in the plasma membrane and cytosol. Additionally, an extremely weak 107 kDa band was detected only in the cytosol. The reactions were not detected in round spermatids. In elongating Stage VI spermatids, the plasma membrane and the granular structure within the cytoplasm were intensely positive, and most intense after the appearance of new round spermatids in the lower layer (Stage I). The reactions were observed neither in the other organs of the common tree shrew nor in the testes of other animals, indicating that TSd-1 antigen is specific to the spermatogenic cells of the common tree shrew, and may act on elongating or matured spermatids.

Animals↗
PubMed1998

Geographical variation of mandible size and shape in the Ryukyu wild pig (Sus scrofa riukiuanus).

We measured adult mandibles of Ryukyu wild pigs from Amami-Oshima, Kakeroma, Okinawa, Ishigaki and Iriomote Islands. The size cline was not statistically recognized among the populations of Nansei Islands. The Ishigaki population was significantly larger than Iriomote one in mandible length. Some measurement ratios indicated that the ramus is enlarged laterally and that the body of mandible is dorso-ventrally developed in Ishigaki and Iriomote populations. The Amami-Oshima mandibles were relatively smaller than those of Okinawa and Iriomote populations in length item of body of mandible. These results will contribute to the zoo-archaeology on the historical change of size and shape in the island populations, and to the evolutionary biology on the morphological adaptation of this animal.

Animals↗
PubMed1998

Functional relationship between muscles of mastication and the skull with enlarged orbit in the Baikal seal (Phoca sibirica).

We expected that the enlarged area of zygomatic arch, one of some skull characters adapted for enlarged eye, has an influence on form and function of muscles of mastication in the Baikal seal (Phoca sibirica). So, in this species, the Mm, masseter, temporalis, pterygoidei, digastricus were observed in the macroscopic level. The skull characters related to these muscles were also compared between the Baikal seal and a close-related species, the ringed seal (Phoca hispida). The Mm, masseter and temporalis were well-developed using the enlarged attachment area of zygomatic arch. In contrast, the M. digastricus is suggested to be not so important in the Baikal seal, because the temporal bone is not so developed as in the ringed seal. It is suggested that the Baikal seal has especially developed the Mm. temporalis and masseter using an enlarged area of zygomatic arch among Pusa species. We also suggest that the robust temporal bone is equipped to have the M. digastricus developed as a main retractor of mandibular body in the ringed seal.

Adaptation, Biological↗
PubMed1998

Multivariate analysis of mandible in the Ryukyu wild pig (Sus scrofa riukiuanus).

We measured adult mandibles of Ryukyu wild pig (Sus scrofa riukiuanus) from Tokunoshima Island and compared the osteometrical data with those from six Nansei Islands. The mandibles in Tokunoshima Island were larger than those from Amami-Oshima and Okinawa Islands in some measurements. We concluded that the size cline was not statistically recognized among populations. In the principal component analysis, the size cline was also denied, and the separation could be made among island populations in female. It is suggested that the populations in Tokunoshima and Okinawa Islands may be different from those in Amami-Oshima, Kakeroma, Ishigaki and Iriomote Islands in skull proportion.

Aging↗
PubMed1997

Sensory feedback contributes to early movement-evoked fields during voluntary finger movements in humans.

Neuromagnetic field changes accompanying voluntary movement in humans ('movement-evoked fields' or MEFs) were recorded over the scalp using a whole-head MEG system during the performance of self-paced finger movements in order to determine the contribution of sensory feedback to the generation of these brain responses. It was found that cooling the subject's arm resulted in delays of 8 ms or more in the latency of the early movement-evoked field component (MEFI). These delays were attributed to increases in conduction times in the afferent pathways as confirmed by electrically evoked somatosensory responses and suggest a peripheral origin of the MEFI. In a second experiment, we demonstrated the effects of sensory input to the contralateral hand during a simple button pressing task in 4 subjects. The results indicated that responses over the hemisphere ipsilateral to the side of movement which resembled previously reported ipsilateral MEFs can be elicited by the spread of mechanical stimulation to opposite side of the body when a mechanical trigger is used. These experiments provide further evidence that early movement-evoked fields produced by unilateral finger movements are observed primarily over the contralateral somatosensory cortex and represent sensory feedback to the somatosensory cortex from the periphery.

Arm↗
PubMed1997

Introduction of DNA into rat liver with a hand-held gene gun: distribution of the expressed enzyme, [32P]DNA, and Ca2+ flux.

DNA-coated Au particles were accelerated by pressurized He gas to supersonic velocities for introduction of a gene into cells. Experimental and theoretical analyses both revealed a heterogeneous distribution of the particles per shot (1 mg Au = 2.4 x 10(7) particles with 2 microg [32P] DNA = 2.5 x 10(11) moles). For introduction of genes into the liver of living rats, the best results were obtained with a newly developed hand-held gene delivery system. The beta-galactosidase gene introduced into rat liver with Au particles by He at 250 psi was expressed (1.2 microunits/microg protein) in a limited area of the liver surface (8 x 8 mm, depth 0.5 mm). When the same gene gun was used on a monolayer of cultured COS7 cells (about 5 microm thick), cells were lost in the central area of heavy bombardment. Cell death caused by influx of Ca2+ was prevented by the use of the cytosol-type culture medium.

Animals↗
PubMed1997

Human cortico-hippocampal activity related to auditory discrimination revealed by neuromagnetic field.

We carried out multi-dipole estimation and pursued spatio-temporal brain activity on a time scale of several milliseconds during an auditory discrimination task using a whole-cortex type SQUID system. Neuronal activities were estimated in the medial (hippocampus, parahippocampal gyrus, etc.) and lateral temporal cortices (superior and middle temporal gyri, etc.), the dorsolateral prefrontal cortex (middle and inferior frontal gyri, etc.) and the parietal cortex (supramarginal gyrus, etc.) in the 280-400 ms latency range. The activity in the posterior hippocampal region was the most prominent and long-lasting in parallel with the activities in the other regions. Therefore, the posterior hippocampal region is a central structure engaged in auditory discrimination. The whole-cortex neuromagnetic measurements provided the possibility of imaging the time-varying activities of the human cortico-hippocampal neural networks.

Adult↗
PubMed1997

Renal tubular abnormalities in hydrops fetalis: a histological and immunohistochemical study.

An immunohistochemical study of renal tubule cell differentiation in hydrops fetalis was performed using antibodies against lysozyme, CD15, keratin, epithelial membrane antigen and Leu-7, and formalin-fixed, paraffin-embedded sections of tissue that was obtained at autopsy. In 3 cases among 17 cases of hydrops fetalis (17.6%) there was a marked decrease in the number of cells stained positively for lysozyme, suggesting abnormal differentiation of the cells of the proximal convoluted tubules. This is the first report concerning the abnormalities of the renal tubular epithelium in hydrops fetalis.

CD57 Antigens↗
PubMed1997

Mechanistic studies on metabolic chiral inversion of 4-(4-methylphenyl)-2-methylthiomethyl-4-oxobutanoic acid (KE-748), an active metabolite of the new anti-rheumatic agent 2-acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid (KE-298), in rats.

The chiral inversion properties of 4-(4-methylphenyl)-2-methylthiomethyl-4-oxobutanoic acid (KE-748), an active metabolite of 2-acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid (KE-298), were compared with those of ibuprofen in rats. After administration of R(-)-[2 alpha-2H]KE-748, S(+)-KE-748 was present in the rat plasma, and the deuterium atoms of the S(+)-enantiomer were almost all replaced by hydrogen atoms. After administration of S(+)-[2 alpha-2H]KE-748, the deuterium content of S(+)-KE-748 in the plasma remained intact. In the in vitro study, using a cell-free system and rat liver homogenates, the chiral inversion of ibuprofen was apparent when both CoA and ATP were present; however, KE-748 was not inverted. In the study on isolated rat hepatocytes, the unidirectional chiral inversion from R(-)-to S(+)-enantiomer was observed for both ibuprofen and KE-748. When R(-)-ibuprofen was incubated with medium and long chain fatty acids (carbon chain length C6 to C16), using isolated hepatocytes, the chiral inversion decreased significantly. On the other hand, when R(-)-KE-748 was incubated with short and medium chain fatty acids (carbon chain length C3 to C8), chiral inversion was inhibited markedly. To induce hepatic microsomal long chain fatty acid CoA ligase, rats were treated with clofibric acid (CF rats). In both in vitro and in vivo experiments on CF rats, chiral inversion from R(-)-to S(+)-ibuprofen was enhanced significantly compared with that in controls, whereas the enhancement was not observed in the case of R(-)-KE-748. There was no influence of benzoic acid, a typical substrate on medium chain fatty acid CoA ligase in the mitochondrial matrix, on chiral inversion of R(-)-ibuprofen, using, isolated hepatocytes. In contrast, the chiral inversion from R(-)-to S(+)-KE-748 was strongly inhibited in the presence of benzoic acid. These results indicate that chiral inversion of R(-)-KE-748 may proceed via formation of the CoA-thioester intermediate with loss of the 2 alpha-methine proton, in a manner similar to that seem with R(-)-ibuprofen. However, the enzymes needed to form CoA-thioester of R(-)-KE-748 differ from those for R(-)-ibuprofen.

Animals↗
PubMed1997

Cardiac-like musculature of the intrapulmonary venous wall of the long-clawed shrew (Sorex unguiculatus), common tree shrew (Tupaia glis) and common marmoset (Callithrix jacchus).

BACKGROUND: The cardiac-like musculature is distributed not only in the heart wall but also in the intrapulmonary venous wall in a few species of insectivores. It has been suggested that the evolutionary origin of venous cardiac-like musculature may be traceable to a basic stock of certain mammalian lines of descent. So, it is important to clarify whether the musculature may be a common structure in lower mammals from insectivores to primates and to examine the functional significance of the structure. METHODS: The distribution of cardiac-like musculature in the intrapulmonary venous wall of the long-clawed shrew (Sorex unguiculatus), common tree shrew (Tupaia glis), and common marmoset (Callithrix jacchus) was observed by light and electron microscopy. The presence of atrial natriuretic polypeptide (ANP) was examined in the musculature by immunohistochemistry. RESULTS: All three species contained cardiac-like myocytes in the tunica media of intrapulmonary venous wall. In the common tree shrew and the common marmoset, cardiac-like musculature was found in the small intrapulmonary vein of 150-200 microns in diameter, while, in the long-clawed shrew, it was distributed even in the intrapulmonary vein of 30 microns in diameter. Ultrastructure of myocytes was fundamentally similar to that of atrial myocytes in the long-clawed shrew and the common tree shrew. The presence of atrial natriuretic polypeptide (ANP) was also demonstrated by immunohistochemistry in the intrapulmonary venous walls of common tree shrews. CONCLUSIONS: The results indicate that the pulmonary venous cardiac-like musculature occurs in the lower eutherian mammals from insectivores to primitive primates. The musculature is thought to act as a regulatory pump in pulmonary circulation and as an endocrine apparatus of ANP.

Animals↗
PubMed1997

Stereoselective disposition and chiral inversion of KE-298, a new antirheumatic drug, in rats.

The present study was an attempt to elucidate the relationship between stereoselective pharmacokinetics and protein binding of KE-298 and its active metabolites, deacetyl-KE-298 (M-1) and S-methyl-KE-298 (M-2). Metabolic chiral inversion was also investigated. The levels of unchanged KE-298 in plasma after oral administration of (+)-(S)-KE-298 to rats were lower than those of (-)-(R)-KE-298, whereas the levels of M-1 and M-2 after administration of (+)-(S)-KE-298 were higher than after (-)-(R)-KE-298. In vitro, rat plasma protein binding of (+)-(S)-KE-298 was lower than that of (-)-(R)-KE-298. In contrast, the binding of (+)-(S)-M-1 and (+)-(S)-M-2 was higher than that of (-)-(R)-M-1 and (-)-(R)-M-2. Displacement studies revealed that the (+)-(S) and (-)-(R)- enantiomers of KE-298 and their metabolites bound to the warfarin binding site on rat serum albumin. These results suggested that the stereoselective plasma levels in KE-298 and its metabolites were closely related to enantiomeric differences in protein binding attributed to quantitative differences in binding to albumin rather than to the different binding sites. Unidirectional chiral inversion was detected after oral administration of either (-)-(R)-KE-298 or (-)-(R)-M-2 to rats both yielding (+)-(S)-M-2.

Animals↗
PubMed1997

An enzyme- linked immunosorbent assay for heparan sulfate proteoglycans.

An enzyme- linked immunosorbent assay (ELISA) for heparan sulfate proteoglycan (HSPG) was developed based on the high affinity binding profile of HSPG to lipoprotein lipase (LPL). LPL was shown to bind to precoated HSPG in dose dependent manner and was determined spectrophotometrically using specific anti- LPL antibody. This ELISA allowed to evaluate HSPG produced by PC12 cell with clear linearity at range of 10 - 500 ng/ml. Soluble chondroitin sulfate proteoglycan (CSPG) from rat brain, which was not detectable by this method, did not exhibit any inhibitory effects on affinity binding of HSPG to LPL, even if 8 times higher concentrations of CSPG to HSPG was added. The sensitivity of this ELISA was about 100 times higher than that of conventional carbazole reaction method. These findings indicated its potential usefulness of this method for measuring small amounts of HSPG capable of binding to LPL and for studying biological implications of HSPG - LPL interaction.

Animals↗
PubMed1997

Pharmacokinetic study of aniracetam in elderly patients with cerebrovascular disease.

The clinical pharmacokinetics of the cognitive enhancer, aniracetam (200 mg), was studied in elderly patients with cerebrovascular disease (CVD) and compared with those of young healthy volunteers. Six female hospitalized patients (mean age 84.5 years) were used in this study. The serum level of anisic acid and p-methoxyhippuric acid, major metabolites of aniracetam, reached a peak at 2 h after oral administration, and returned to basal level by 6 h. Mean creatinine clearance was 20-30 ml/min. The t1/2 of metabolites was increased by 4- to 7-fold in the elderly patients compared with young volunteers. This study showed that tmax, t1/2, and AUC were enlarged in the elderly; however, no clinical side effects were observed.

Adult↗
PubMed1997

Modified neck muscular system of the giraffe (Giraffa camelopardalis).

The muscular and skeletal systems of the long neck were morphologically examined in order to clarify their modification and their functional significance in the giraffe (Giraffa camelopardalis). The longissimus, the thoracic and cervical, spinalis and semispinalis, the cranial and caudal head oblique, and the multifidus muscles, and the nuchal ligament were observed at their origin and insertion. The atlas, axis, and the third cervical vertebra were measured and examined. The modified spinous processes provided the large attachment surface for the strong nuchal ligament and for the muscles of the axis and other cervical vertebrae, while the muscle tendons had their origin in the ventrocaudally-enlarged transverse process. It is concluded that the modified muscles with their expanded belly and tendon have the functions of occupying the interspace among long vertebrae, and also of supporting the head and neck by means of their wide attachment to the altered vertebral processes.

Animals↗
PubMed1997

Genes of human ATP synthase: their roles in physiology and aging.

The reaction of ATP synthase (F0F1) is the final step in oxidative phosphorylation (OXPHOS). Although OXPHOS has been studied extensively in bacteria, no tissue-specific functions nor bioenergetic disease, such as mitochondrial encephalomyopathy and aging occur in these organisms. Recent developments of the Human Genome Project will become an important factor in the study of mammalian bioenergetics. To elucidate the physiological roles of human F0F1, genes encoding the subunits of F0F1 were sequenced, and their expression in human cells was analyzed. The following results were obtained: A. The roles of the residues in F0F1 are not only to transform the energy of the electrochemical potential (delta mu H+) across the membrane, but also to respond rapidly to the changes in the energy demand by regulating the intramolecular rotation of F0F1 with the delta mu H+ and the inhibitors of the ATPase. B. The roles of the control regions of the F0F1 genes, are to coordinate both mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) depending on the energy demand of the cells, especially in muscle, C. The cause of the age-dependent decline of ATP synthesis has been attributed to the accumulation of mutations in mtDNA. However, the involvement of nDNA in the decline is also important because of telomere shortening in somatic cells, and age-dependent mtDNA expression analyzed with rho degree cells (cells without mtDNA).

Aging↗
PubMed1997

Foramen magnum schwannoma with an unusual clinical presentation: case report.

This case report illustrates a patient with a unilateral localized epidural schwannoma at C1-2 level, showing contralateral spinal cord symptoms and signs. The clinical presentation was compared with the neuroradiological examinations showing an epidural cord tumor at the right C1-C2 level. However, the neurological examination revealed contralateral hemiparesis and ipsilateral hemihypoalgesia, indicating a contralateral Brown-Sequard syndrome. We presumed with this slow growing tumor, contralateral cord involvement may result from counter pressure on the spinal cord, which may be generated by cord deviation and by frequent neck rotation.

Brain Neoplasms↗
PubMed1997

A novel mutation of a leucine residue in coil 1A of keratin 9 in epidermolytic palmoplantar keratoderma.

Keratin 9 mutation was examined in a Japanese kindred of epidermolytic palmoplantar keratoderma (EPPK), which is a dominantly inherited autosomal disorder of keratinization characterized by diffuse thickening of the palms and soles and by epidermolytic hyperkeratosis histologically. We report herein a novel mutation, a C --> G transversion at nucleotide position 541 that converts a leucine residue (CTC) to a valine (GTC) at codon 159. As in all other reported cases of keratin 9 mutation in EPPK, this mutation lies within the highly conserved coil 1A of the rod domain, which is considered to play a role in the correct alignment of the coiled-coil molecules.

Amino Acid Sequence↗