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Biomedical subjects

H Noguchi

Publications and source records attributed to H Noguchi.

At least 145 records · Page 8Linked to original sources
PubMed1998

Developmental changes in dopamine levels in larvae of the fly Chymomyza costata: comparison between wild-type and mutant-nondiapause strains.

Dopamine and two related catecholamines, L-3,4-dihydroxyphenylalanine (DOPA) and N-acetyl dopamine (NADA), were analyzed in whole body and tissue samples taken throughout late larval development of the drosophilid fly Chymomyza costata, which enters facultative diapause as a mature 3rd instar larva in response to short photophase. Wild-type (W) and mutant-nondiapause (M) strains reared under diapause inducing (d) and preventing (nd) photophases were compared. Developmental changes in the whole body of dopamine levels showed some general features irrespective of fly strain and rearing conditions: sharp major peaks during moult from second to third instar larva and during pupariation; lower minor peaks around the middle of both 2nd and 3rd instars. Significant differences between the strains and conditions were also found: dopamine levels were lower throughout the 2nd instar and during the 2nd to 3rd instar moult of mutant strain larvae (M/d) as compared to wild-type larvae (W/nd and W/d); while the late 2nd and late 3rd instar larvae destined to diapause (W/d) maintained relatively high dopamine concentrations, their counterparts destined to continuous development (W/nd and M/d) significantly decreased dopamine levels prior to the 2nd to 3rd instar moult or pupariation. Possible relationship between the dopamine levels and diapause induction/onset in C. costata larvae is discussed. Integument contained more than 90% of the dopamine found in the whole body. The gut and central nervous tissues showed relatively low pools of dopamine, only trace amounts were detected in haemolymph and no dopamine was found in fat body. DOPA levels were low and stable throughout larval development of both W and M strains and under both conditions. NADA levels peaked during second halves of 2nd and 3rd instars of both strains, then dropped to trace levels and were elevated again during 2nd to 3rd instar moult as well as in tanned prepupae. No elevation of NADA levels was recorded in 3rd instar W/d larvae which entered diapause.

Journal Article↗
PubMed1998

Polygalasaponins XLII-XLVI from roots of Polygala glomerata.

Five new oleanane-type saponins, polygalasaponins XLII-XLVI, along with two known saponins were isolated from the roots of Polygala glomerata Lour. The structures of polygalasaponins XLII-XLVI were elucidated as 3-O-beta-D-glucopyranosyl presenegenin 28-O-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl- (1-->2)-{4-O-[(E)-3,4-dimethoxycinnamoyl]}-beta-D-fucopyranosyl ester, 3-O-beta-D-glucopyranosyl presenegenin 28-O-beta-D-galactopyranosyl-(1-->4)-beta-D-xylopyranosyl-(1-->4)- alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-arabinopyranosyl- (1-->3)]-[4-O-(E)-p-methoxycinnamoyl]-beta-D-fucopyranosyl ester, 3-O-beta-D-glucopyranosyl presenegenin 28-O-beta-D-galactopyranosyl-(1-->4)-beta-D-xylopyranosyl-(1-->4)- alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-glucopyranosyl- (1-->3)]-{4-O-[(E)-3,4-dimethoxycinnamoyl]}-beta-D-fucopyranosyl ester, 3-O-beta-D-glucopyranosyl presenegenin 28-O-beta-D-galactopyranosyl-(1-->4)-beta-D-xylopyranosyl-(1-->4)- alpha-L-rhamnopyranosyl-(1-->2)-[6-O- acetyl-beta-D-glucopyranosyl-(1-->3)]-{4-O- [(E)-3,4-dimethoxycinnamoyl]}-beta-D-fucopyranosyl ester, 3-O-beta-D- glucopyranosyl presenegenin 28-O-beta-D-galactopyranosyl-(1-->4)- beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl- (1-->2)-[6-O-acetyl-beta-D-glucopyranosyl-(1-->3)]-{4-O-[(Z)-3, 4-dimethoxycinnamoyl]}-beta-D-fucopyranosyl ester, respectively, on the basis of spectroscopic and chemical evidence.

Carbohydrate Sequence↗
PubMed1998

Oligosaccharide polyesters from roots of Polygala glomerata.

Seven new sucrose and oligosaccharide esters, glomeratoses A-G, together with four known compounds, 3-O-[(E)-3,4,5-trimethoxycinnamoyl]-beta-D-fructofuranosyl-(2-->1) - (6-O-benzoyl)-alpha-D-glucopyranoside, 3-O-(E)-sinapoyl-beta-D-fructofuranosyl-(2-->1)-[6-O-(E)-sinapo yl]-alpha-D- glucopyranoside, tenuifoliside C and reiniose G were isolated from the roots of Polygala glomerata. Glomeratoses A-G were elucidated as 3-O-[(E)-3,4,5-trimethoxycinnamoyl]-beta-D-fructofuranosyl-(2-->1) -alpha-D- glucopyranoside, 3-O-(E)-sinapoyl-beta-D-fructofuranosyl-(2-->1)-[6-O-(E)-p- coumaroyl]-alpha-D-glucopyranoside, 3-O-[(E)-3,4,5-trimethoxycinnamoyl]-beta-D-fructofuranosyl-(2-->1) -[6-O-(E)- p-coumaroyl]-alpha-D-glucopyranoside, 3-O-[(E)-3,4,5-trimethoxycinnamoyl]-beta-D-fructofuranosyl-(2-->1) -[6-O-(E)- 3,4,5-trimethoxycinnamoyl]-alpha-D-glucopyranoside, 1-O-{6-O-[3-O-(E,E)-(beta, beta'-bis-sinapoyl)-beta-D-fructofuranosyl]}-alpha- D-glucopyranoside intramolecular ester, 1-O-(E)-p-coumaroyl-(3-O-benzoyl)-beta-D- fructofuranosyl-(2-->1)-[beta-D-glucopyranosyl-(1-->2)]-[6-O-acetyl-beta -D- glucopyranoysl-(1-->3)]-[4-O-(E)-feruloyl]-(6-D-acetyl)-alph a-D- glucopyranoside, 1-O-(E)-p-coumaroyl-(3-O-benzoyl)-beta-D-fructofuranosyl-(2-->1)-[ beta-D- glucopyranosyl-(1-->2)]-[6-O-acetyl-beta-D-glucopyranoside-(1-->3)]-{4-O - [4-O-beta-D-glucopyranosyl-(E)-feruloyl]}-[6-O-(E)-p-coumaroyl+ ++]-alpha- D-glucopyranosyl, respectively, on the basis of chemical and spectral evidence.

Carbohydrate Conformation↗
PubMed1998

Immunohistochemical analysis of cell cycle regulatory gene products in normal trophoblast and placental site trophoblastic tumor.

Intermediate trophoblast (IT) rarely gives rise to a placental site trophoblastic tumor (PSTT) To examine the different growth mechanisms present in normal and neoplastic IT, the expression of cell cycle regulatory molecules was compared at normal implantation sites and in PSTTs. Normal implantation sites in early gestation (19 patients) and PSTTs (6 patients) were immunohistochemically studied using antibodies against cytokeratin, human chorionic gonadotropin, and human placental lactogen to identify IT, and antibodies against Ki-67, cyclins (A, B, D1, and E), cyclin-dependent kinases (cdks), and p53 to investigate the proliferative activity of the trophoblast. Marked proliferative activity was observed in the trophoblast of the cell columns. Normal IT exhibited a very low labeling index for Ki-67, with negative expression for cdks and cyclins, except for cyclins B and E. The tumor cells of PSTT exhibited a high labeling index for Ki-67 with positive expression for all the cyclins and cdks examined. Expression of p53 was identified in tumor cells of PSTTs and the distribution of p53-positive cells correlated topographically with that of the cyclin A-positive cells. The transformed IT of PSTT has high proliferative activity with an abnormal expression of cell cycle regulatory molecules, which is not observed in normal IT.

Adult↗
PubMed1998

A pediatric case of atypical Mycobacterium avium infection of the skin.

We report a case of cutaneous atypical mycobacteriosis in a 12-year-old healthy girl due to Mycobacterium avium. The cutaneous symptoms were three well-defined subcutaneous nodules on both buttocks and on the posterior surface of the left thigh. One had a fistulous opening on the skin surface. Histopathological examination revealed epithelioid cell granulomas surrounded by dense lymphocytic infiltration and acid-fast bacteria were seen with modified periodic acid-carbol fuchsin staining. Using Ogawa's medium at 37 degrees C, acid-fast bacteria were isolated from the biopsied specimen and identified by the DNA-DNA hybridization method as Mycobacterium avium. In drug susceptibility test, these were resistant to all antituberculous drugs. Oral administration of minocycline 100 mg/day for two months had little effect on the two remaining lesions, which were therefore excised. Based upon reported cases of Mycobacterium avium complex, we considered that our pediatric patient with multiple intradermal or subcutaneous nodules on the buttocks and the thigh exhibited the characteristic symptoms of M. avium infection.

Administration, Oral↗
PubMed1998

Tracheal intubation through the intubating laryngeal mask airway (LMA-Fastrach) in patients with difficult airways.

The intubating laryngeal mask airway was used in 31 adult patients in whom tracheal intubation was known or suspected to be difficult. The intubating laryngeal mask airway was successfully inserted in 30 patients and provided a clinically patent airway. In the remaining one patient it was impossible to insert the device correctly. Tracheal intubation through the device was successful in 28 of 30 patients (93%). These results suggest that the intubating laryngeal mask airway has a potential role for tracheal intubation in adult patients with difficult airways.

Adolescent↗
PubMed1998

Gastric epithelial cells secrete a PDGF-like peptide, a potent mitogen for human gastric fibroblasts.

To investigate whether gastric epithelial cells secrete growth factors involved in stromal cell growth, we examined the effects of conditioned media obtained from gastric cancer cells on murine BALB/c 3T3 cells and primary cultured human gastric fibroblasts. Conditioned media from MKN-1 gastric cancer cells were applied to a heparin-affinity column. The fraction eluted from the column at 0.4 M NaCl stimulated DNA synthesis and phosphorylation of PDGF alpha-receptors on tyrosine in BALB/c 3T3 cells. The fraction-induced stimulation of DNA synthesis in gastric fibroblasts was more marked than in BALB/c 3T3 cells. However, the fraction failed to stimulate DNA synthesis in CHO-ER cells overexpressing EGF receptors and phosphorylation of PDGF beta-receptors on tyrosine in BALB/c 3T3 cells. Immunoblot analysis of the media confirmed that PDGF-AA-like peptides are released from gastric cancer cells, immortalized gastric epithelial cells, and primary cultured gastric epithelial cells. Anti-PDGF neutralizing antibodies produced only a partial inhibition of 0.4 M NaCl fraction-induced enhanced DNA synthesis. Thus, in addition to PDGF-AA peptide, other bioactive substance(s) are probably released from MKN-1 gastric cancer cells. Our results suggest that gastric epithelial cells secrete PDGF-AA-like peptides responsible for stromal cell growth through paracrine mechanisms.

3T3 Cells↗
PubMed1997

Brain-derived neurotrophic factor reduces blood glucose level in obese diabetic mice but not in normal mice.

Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family. However, it is not yet known if BDNF works on the endocrine system itself. Here we report that BDNF improves hyperglycemia in obese diabetic animals. BDNF reduced the blood glucose level in obese db/db diabetic mice in which the effect of BDNF was age-dependent and high under the condition of hyperinsulinemia, while BDNF showed no effect on non-diabetic db/m mice. These results suggest that BDNF ameliorates insulin resistance by enhancing insulin action in peripheral tissues. Furthermore, BDNF was found to reduce the plasma insulin level in db/db mice. Among the neurotrophin family, NT-3 also reduced the blood glucose level in db/db mice. These results provide a novel insight that neurotrophin functions on the endocrine system as well as the nervous system.

Animals↗
PubMed1997

Role of dopamine at the onset of pupal diapause in the cabbage armyworm Mamestra brassicae.

Experiments were conducted to examine the relationship between an onset of diapause and dopamine (DA) content in the cabbage armyworm Mamestra brassicae during pupation. The DA levels were significantly higher in haemolymph, integument and brain-central nervous system of diapause-destined pupae than in non-diapause-destined pupae. The elevated level of the integumental DA content was demonstrated to be due to an increase in dopa decarboxylase activity in diapausing pupal integuments through an enhancement of transcript levels of this enzyme. Elevation of the DA level accomplished by feeding L-DOPA to last instar larvae induced a diapause-like state in more than 50% of the pupae under long daylengths.

Adaptation, Physiological↗
PubMed1997

BDNF prevents and reverses adult rat motor neuron degeneration and induces axonal outgrowth.

To assess the therapeutic potential of brain-derived neurotrophic factor (BDNF) in clinics, we extensively investigated the effects of BDNF on adult motor neurons in a rat spinal root avulsion model. Intrathecal administration of BDNF immediately after the spinal root avulsion greatly protected against the motor neuron cell death. BDNF also showed a protective effect on the atrophy of soma and on the reduction of transmitter-related enzymes such as choline acetyl transferase and acetylcholine esterase. Very interestingly, BDNF induced axonal outgrowth of severely damaged motor neurons at the avulsion site. The BDNF administration following 2-week treatment with phosphate-buffered saline after avulsion prevented further augmentation of cell death and reversed cholinergic transmitter-related enzyme deficiency. BDNF was demonstrated to possess a wide variety of biological effects on survival, soma size, cholinergic enzymes, and axonal outgrowth of adult motor neurons. These results provide a rationale for BDNF treatment in motor neuron diseases such as spinal cord injury and amyotrophic lateral sclerosis.

Acetylcholinesterase↗
PubMed1997

Processing of cathepsins L, B and D in psoriatic epidermis.

Proteinase activity is increased in psoriatic epidermis. To elucidate the involvement of enzymes in psoriatic epidermis, the expression of cathepsins, L, B and D was investigated by Western blotting and immunohistological studies. Normal epidermis contained abundant inactive precursors (39 kDa) of cathepsins L and B and an inactive intermediate form (45 kDa) of cathepsin D. Cathepsin L in psoriasis was processed to a variable extent from the precursor to a single-chain form (30 kDa) and a mixture of single- and heavy-chain (25 kDa) forms of the active mature enzyme, corresponding to the immunohistological staining patterns 'diffuse dense', 'small granular', and unevenly distributed 'condensed granular'. Cathepsin B showed a mixture of precursor form (39 kDa) and single-chain (30 kDa) forms and was expressed as a 'diffuse dense' staining pattern in the mid-spinous layer and as a 'condensed' pattern in the upper spinous and granular layers. Cathepsin D was processed to the heavy-chain (31 kDa) form of activated mature enzyme with small granular staining and a mixture of heavy-chain and degraded protein (28 kDa) with larger and more condensed granular staining. The distribution patterns of 'small granular' cathepsin L, and of cathepsins B and D expression in suprabasal keratinocytes were very similar to that of involucrin. After complete clinical resolution of psoriasis by 8-methoxypsoralen plus UVA treatment, the expression of the three cathepsins was normalized. These results suggest that cathepsins L, B and D in forms activated to a variable extent may be involved in the pathology of psoriasis.

Adolescent↗
PubMed1997

Oligosaccharide polyesters from roots of Polygala fallax.

Five new oligosaccharide polyesters, fallaxoses A-E, along with four known ones, reiniose D, senegose G, tenuifolioses C and P, were isolated from the roots of Polygala fallax. Fallaxoses A-E were elucidated as 3-O-{4-O-[beta-D-glucopyranosyl-(1-->4)- alpha-L-rhamnopyranosyl]-feruloyl}-beta-D-fructofuranosyl- (2-->1)-(4,6-di-O-benzoyl)-alpha-D-glucopyranoside, 3-O-{4-O-[beta-D-glucocopyranosyl-(1-->3)-(2-O-acetyl)- alpha-L-rhamnopyranosyl]-feruloyl}-beta-D-fructofuranosyl-(2-->1)- (4, 6-di-O-benzoyl)-alpha-D-glucopyranoside, 1-O-p-coumaroyl-(3-O-benzoyl)-beta-D-fructofuranosyl-(2-->1)- [beta-D-glucopyranosyl-(1-->2)]-[6-O-acetyl-beta-D-glucopyranosyl- (1-->3)]-(4-O-p-coumaroyl)-alpha-D-glucopyranoside, 1-O-p-coumaroyl-(3-O-benzoyl)-beta-D-fructofuranosyl-(2-->1)- [beta-D-glucopyranosyl-(1-->2)]-[6-O-acetyl-beta-D-glucopyranosyl-(1-->3 )]-(4-O-feruloyl)-alpha-D-glucopyranoside, 1-O-feruloyl-(3-O-benzoyl)-beta-D-fructofuranosyl-(2-->1)- [beta-D-glucopyranosyl-(1-->2)]-[beta-D-glucopyranosyl- (1-->3)-(6-O-acetyl)-beta-D-glucopyranosyl-(1-->3)]- (6-O-feruloyl)-alpha-D-glucopyranoside, respectively, by spectroscopic and chemical means.

Carbohydrate Conformation↗
PubMed1997

Changes in jaw movement and jaw closing muscle activity after orthodontic correction of incisor crossbite.

The possible influences of the direction of occlusal loading delivered to the incisors in the sagittal direction during chewing on jaw movement and jaw closing muscle activity were investigated. Ten healthy children with crossbite of one or two incisors on the right side were selected. Each subject chewed a piece of chewing gum on the right side, and jaw displacements and electromyographic signals from the posterior temporalis and superficial masseter muscles on the ipsilateral side were sampled simultaneously. After orthodontic correction of the incisor crossbite relationship, identical records were taken. The inclinations of the gliding contacts for each posterior tooth in the lateral jaw excursion position were consistent before and after the treatment. The posttreatment records showed broader jaw movement patterns in the frontal view and faster jaw movement velocity in the lateral direction at a level close to the habitual maximum intercuspation position, when compared with the pretreatment records (P < 0.05). The duration of the muscle activity and the incidence of the silent periods of the masseter muscle during chewing significantly decreased after the treatment (P < 0.05). The current results give a neurophysiologic rationale for explaining the significance of orthodontic treatment in improving lowered masticatory efficiency in the way that the change in direction of the occlusal load achieved by tooth movement influences on the periodontal sensory input, which, in turn, modifies the trigeminal motor output and thus, eventually, jaw muscle activities.

Bite Force↗
PubMed1997

V170 area plays an essential role in the biological activity of human ciliary neurotrophic factor.

The structure-function relationships of human ciliary neurotrophic factor (CNTF) were analyzed by mutagenic means. Amino acid substitutions at helix D caused marked changes in the biological activity of CNTF, suggesting that the residues at helix D of CNTF participate in receptor recognition. In particular, both the cell survival-promoting activity and receptor binding ability of V170 mutant CNTF proteins correlated well with the hydrophobicity of amino acids at position 170. The reduction of hydrophobicity at position 170 resulted in a loss of biological activity, indicating that the hydrophobicity of V170 is essential for the receptor binding and cell survival-promoting activity. Substitutions of R171 or D175 evoked very little folding ability and negated the biological activity of CNTF. As R171 and D175 interact electrostatically with each other and with E75 and R72, respectively, these interactions would be indispensable for stabilizing the whole CNTF protein and for maintaining the structure of the receptor binding epitope.

Cell Survival↗
PubMed1997

Construction and characterization of ciliary neurotrophic factor (CNTF) antagonists: microenvironmental difference in the CNTF receptor between rat and chicken cells for recognizing the D1 cap region.

Antagonistic mutants of ciliary neurotrophic factor (CNTF) were constructed and their properties characterized. K155A and K155W mutants lost cell survival promoting activity for chicken dorsal root ganglion (DRG) neurons and inhibited the activity of the wild type. However, they retained slight agonistic activity for the survival of rat DRG neurons, indicating there is a difference between chicken and rat cells for receptor recognition around the D1 cap region including K155 residue. The chicken receptor recognizes the D1 cap region more strictly than does the rat receptor. The substitution of F152, which locates at the top of the D1 cap region, was combined with the K155A mutation. A combination of the two mutations gave an antagonistic feature to not only chicken but also rat cells. Both F152S/K155A and F152D/K155A mutants lacked cell survival promoting activity and had an antagonistic effect on rat DRG neurons. The three-dimensional structure of CNTF suggests the following. F152 and K155 bind to the receptor with hydrophobic and electrostatic interactions, respectively. F152 locates close to L156 with a van der Waals contact, and K155 contacts with Q42 through a hydrogen bond. Both interactions play indispensable roles in maintaining the structure around the D1 cap region of CNTF.

Animals↗
PubMed1997

Induction of cyclooxygenase 2 in gastric mucosal lesions and its inhibition by the specific antagonist delays healing in mice.

BACKGROUND & AIMS: The role of two forms of cyclooxygenase (COX-1 and COX-2) in gastric mucosal lesions is not well understood. The regulation of both forms of COX and the effect of COX-2 on the repair process of gastric mucosal lesions in mice were investigated. METHODS: Gastric mucosal erosions and ulcers were induced experimentally in mice. The level of COX messenger RNA (mRNA) was determined by reverse-transcription polymerase chain reaction. COX proteins were detected by Western blot analysis, and COX activity was determined in the presence or absence of NS-398, a specific COX-2 antagonist. The effects of long-term administration of NS-398 on gastric ulcers were examined. RESULTS: COX-2 mRNA levels were not detected in control conditions but were high during the acute stages of gastric erosions and ulcers. COX-2 protein was detected 5 days after ulcer induction but not in control mice. Gastric ulceration was not associated with a change in COX-1 mRNA and protein levels. Administration of NS-398 to mice with ulcers at acute stages impaired the healing of ulcers. CONCLUSIONS: High levels of COX-2 mRNA and protein during the acute stages of gastric mucosal lesions may be involved in the repair process of these lesions in mice.

Acetic Acid↗
PubMed1997

Yolk sac tumor of the ovary in a conjoined twin.

A 5-year-old conjoined twin girl had a yolk sac tumor of the right ovary. She was admitted to our hospital because of abdominal distension. Comprehensive clinical and radiological investigations revealed a tumor of the right ovary. She underwent right salpingo-oophorectomy. The diagnosis was yolk sac tumor (stage I A), and postoperative chemotherapy (vincristine, actinomycine-D, cyclophosphamide) according to the UK-CCSG was provided. The postoperative course was uneventful with no evidence of recurrence 3 years after surgery. Her twin sister had no tumor. This is the first reported of yolk sac tumor of the ovary in a conjoined twin.

Child, Preschool↗