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H Ogura

Publications and source records attributed to H Ogura.

At least 19 recordsLinked to original sources
PubMed2000

Ruptured retroperitoneal mucinous cystadenocarcinoma with synchronous gastric carcinoma and a long postoperative survival: case report.

We describe an 86-year-old woman with a long survival following surgey for a massive retroperitoneal mucinous cystadenocarcinoma and a synchronous gastric carcinoma. Computed tomography showed a huge tumor with septation and calcification. Upper gastrointestinal radiography showed the additional gastric lesion. At operation, the 23 x 20 x 12-cm retroperitoneal tumor had ruptured. Tumor resection and distal gastrectomy including regional lymph nodes were performed. Mucinous peritoneal implants were removed as completely as possible. Histologically, the mucinous tumor showed limited invasion, whereas the poorly differentiated gastric adenocarcinoma showed no serosal invasion. Among 18 retroperitoneal mucinous cystadenocarcinomas reported in the English literature since 1965, only ours was associated with gastric carcinoma. Despite peritoneal implants, our patient has survived for 6 years without clinical recurrence. As at other sites, retroperitoneal mucinous cystadenocarcinoma often grows slowly. Total removal, even after peritoneal dissemination, can result in long survival.

Adenocarcinoma↗
PubMed2000

Neutralization assay for human group C rotaviruses using a reverse passive hemagglutination test for endpoint determination.

A novel neutralization assay for human group C rotavirus (CHRV) was developed by using a reverse passive hemagglutination (RPHA) test for endpoint determination. In this assay, the neutralization (N)-RPHA test, serial twofold dilutions of sera were mixed with a solution of CHRV that yielded an RPHA test titer of 8 at 3 days after infection. The mixtures were incubated at 37 degrees C for 1 h and were inoculated onto CaCo-2 cell monolayers in a 96-well microplate. Maintenance medium containing 100 microgram of pancreatin per ml was placed in each well. The plate was sealed with sticky plastic film and was incubated at 37 degrees C for 3 days under continuous rotation. Then, the RPHA test titer of each well was determined. The neutralization titer was expressed as the reciprocal of the maximum dilution of the serum that exhibited a fourfold (75%) or greater reduction in the RPHA test titer (8 to 2 or less). Seroconversion of neutralizing antibody was demonstrated by this method in four sets of paired serum specimens from patients with diarrheal disease caused by CHRV. The seroprevalence of CHRV in the general population in Okayama Prefecture was 26.8% by immunofluorescence and 25.5% by the N-RPHA test. The N-RPHA test described here is the first system used to assay for a neutralization antibody against CHRV and is applicable in both clinical and epidemiological settings.

Adolescent↗
PubMed1999

Functional properties of two bombesin-like peptide receptors revealed by the analysis of mice lacking neuromedin B receptor.

The neuromedin B-preferring receptor (NMB-R) is one of the members of the bombesin (BN)-like peptide receptor subfamily in mammals. Previously, we have generated and characterized mice with targeted disruption of the two other BN-like peptide receptors, bombesin receptor subtype-3 (BRS-3) and gastrin-releasing peptide-preferring receptor (GRP-R). Here we describe the generation and analysis of NMB-R-deficient mice to investigate how NMB-R differs from BRS-3 and GRP-R. Compensation for NMB-R deficiency by overexpression of GRP-R and/or BRS-3 was not detected. Although the hypothermic effect of NMB was reduced by 50% in NMB-R-deficient mice, the effect of GRP infusion was comparable to the wild-type mice. In contrast, fundic smooth muscle contraction on stimulation with NMB or GRP was normal in NMB-R-deficient mice. Administration of GRP but not NMB suppressed glucose intake in both normal and NMB-R-deficient mice. These results suggest that the NMB-R has an essential role in thermoregulation, but not for smooth muscle contraction of the fundus or for the suppression of feeding behavior. In addition, the behavioral phenotypes of GRP-R-deficient mice were not observed in NMB-R-deficient mice. These data show that the functions of NMB-R and GRP-R are distinct, with only partial overlap.

Animals↗
PubMed1999

Competitive NMDA receptor antagonists disrupt prepulse inhibition without reduction of startle amplitude in a dopamine receptor-independent manner in mice.

Prepulse inhibition is thought to reflect the operation of the sensorimotor gating system in the brain, and is reduced in schizophrenic patients and in animals treated with non-competitive NMDA receptor antagonists such as phencyclidine and (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine ((+)-MK-801). Previously, we reported that a competitive NMDA receptor antagonist, cis-4-phosphonomethyl-2-piperidine-carboxylate hydrochloride (CGS 19755), also disrupts prepulse inhibition concomitantly with a marked reduction of startle amplitude elicited by pulse alone in rats. In the present study, the effect of NMDA receptor antagonists on prepulse inhibition was tested in mice. In addition, involvement of the dopaminergic system in CGS 19755-induced disruption of prepulse inhibition was examined. When CGS 19755 was subcutaneously administered at 40 and 80 mg/kg, prepulse inhibition was disrupted without any change in the startle amplitude elicited by pulse alone. Intracerebroventricularly administered CGS 19755 disrupted prepulse inhibition at dosages of 0.1 and 0.2 microg/mouse. The same dosages of R-3-(2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (R-CPP), another competitive NMDA receptor antagonist, also decreased prepulse inhibition, while its less active enantiomer, S-CPP, did not affect prepulse inhibition at 0.2 microg/mouse (i.c.v.). A typical neuroleptic, haloperidol, did not significantly improve CGS 19755 (40 mg/kg s.c.)-induced disruption of prepulse inhibition. These results suggest that the disruption of prepulse inhibition by CGS 19755 and R-CPP is NMDA receptor-mediated and dopamine receptor-independent.

Analysis of Variance↗
PubMed1999

Facilitation of NMDAR-independent LTP and spatial learning in mutant mice lacking ryanodine receptor type 3.

To evaluate the role in synaptic plasticity of ryanodine receptor type 3 (RyR3), which is normally enriched in hippocampal area CA1, we generated RyR3-deficient mice. Mutant mice exhibited facilitated CA1 long-term potentiation (LTP) induced by short tetanus (100 Hz, 100 ms) stimulation. Unlike LTP in wild-type mice, this LTP was not blocked bythe NMDA receptor antagonist D-AP5 but was partially dependent on L-type voltage-dependent Ca2+ channels (VDCCs) and metabotropic glutamate receptors (mGluRs). Long-term depression (LTD) was not induced in RyR3-deficient mice. RyR3-deficient mice also exhibited improved spatial learning on a Morris water maze task. These results suggest that in wild-type mice, in contrast to the excitatory role of Ca2+ influx, RyR3-mediated intracellular Ca2+ ([Ca2+]i) release from endoplasmic reticulum (ER) may inhibit hippocampal LTP and spatial learning.

Animals↗
PubMed1999

Hematospermia: an investigation of the bleeding site and underlying lesions.

BACKGROUND: The site of hemorrhage and causative lesions in patients with hematospermia were evaluated using the puncture technique for seminal vesicles and/or müllerian duct cysts under ultrasound guidance. METHODS: Twenty-one patients aged 26-75 years (mean, 49.8 years) underwent transperineal needle aspiration of the seminal vesicles and/or müllerian duct cysts guided by transrectal ultrasonography (TRUS). RESULTS: Dark reddish seminal vesicle fluid was aspirated and the site of bleeding was considered to be the seminal vesicles in 11 patients (52%) (group A). In group A, abnormalities of the seminal vesicles were noted in nine patients (82%). These consisted of dilated seminal vesicles in seven (bilateral in four, unilateral in three), a seminal vesicle cyst in one and seminal vesicle amyloidosis in one. A müllerian duct cyst was confirmed to be the bleeding site in two patients (10%; group B). The bleeding site was estimated to be organs rather than the seminal vesicles in four patients (group C), in all of whom ectopic prostatic tissue was observed in the prostatic urethra. In groups B and C, seminal vesicle abnormalities were not detected by TRUS. In the remaining four patients (group D), failure to aspirate seminal vesicle fluid means that it is unclear whether hemorrhage was from the seminal vesicle or from another source. In group D, ectopic prostatic tissue was demonstrated in the prostatic urethra of three patients and unilateral seminal vesicle dilation was detected by TRUS in one patient. CONCLUSION: Puncture of the seminal vesicles and/or mullerian duct cysts under ultrasonic guidance as well as cystourethroscopy is a useful and minimally invasive examination for determination of the bleeding site responsible for hematospermia.

Adult↗
PubMed1999

Developmental neurotoxicity of phenytoin on granule cells and Purkinje cells in mouse cerebellum.

Phenytoin (PHT) is a primary antiepileptic drug. Cerebellar malformations in human neonates have been described following intrauterine exposure to PHT. The neonatal period of development in the cerebellum in mice corresponds to the last trimester in humans. To examine the neurotoxic effects of PHT in the developing cerebellum, we administered PHT orally to newborn mice once a day during postnatal days 2-4. We observed many apoptotic cells in the external granular layer (EGL) on postnatal day 5, labeled cells in the EGL still remaining 72 h after labeling with 5-bromo-2'-deoxyuridine, and EGL thicker than that in the control on postnatal day 14. These results showed that PHT induced cell death of external granule cells and inhibited migration of granule cells in cerebella. In specimens immunostained with antibody against inositol 1,4,5-trisphosphate receptor type 1, Purkinje cells in the treated group had poor and immature arbors, and partially showed an irregular arrangement. The motor performance of the treated mice in a rotating rod test was impaired, although there were no changes in muscular strength or in walking pattern at the period of maturity. These findings indicate that PHT induces neurotoxic damage to granule cells and Purkinje cells in the developing cerebellum and impairs selected aspects of motor coordination ability.

Animals↗
PubMed1999

Validation study of the in vitro micronucleus test in a Chinese hamster lung cell line (CHL/IU).

We conducted a collaborative validation study, under the auspices of the Japanese Ministry of Labour, on the in vitro micronucleus test to see if it could be used as an alternative to the in vitro chromosome aberration test for evaluation of chemical safety. We used the Chinese hamster lung cell line (CHL/IU), which is the most widely used system for the latter test in Japan, and evaluated 66 chemicals, including clastogens and polyploidy inducers. The cytochalasin B cytokinesis blocking method, which is commonly used in human lymphocyte culture, was applied to the established cell line, but did not improve the detection of chemically-induced micronuclei in continuously growing cells. The highest micronucleus frequencies were obtained at 48 or 72 h continuous treatments. In short treatments (6 h), a 42 h recovery time yielded the best responses. Concordance between the results of the micronucleus test and the chromosomal aberration test was satisfactorily high (88.7%), and we concluded that the in vitro micronucleus test could be used in place of the chromosomal aberration test as a simple and rapid method for detecting clastogens and aneugens in vitro. We also propose a protocol for the test.

Animals↗
PubMed1999

Priming, second-hit priming, and apoptosis in leukocytes from trauma patients.

BACKGROUND: Polymorphonuclear leukocytes (PMNL) play important roles in both host defenses and systemic inflammatory responses after insults. The objectives of this study are to examine the serial changes in PMNL priming and apoptosis in severely injured patients and to evaluate the impact of second hits on primed PMNL function and systemic vascular endothelial damage. METHODS: Twenty-four severely injured patients (mean Injury Severity Score, 31.1 +/- 9.7) were included. Infections were seen as second hits after trauma in seven patients. Oxidative activity, phagocytosis, and apoptosis of PMNL from serial blood samples were measured by flow cytometry. Oxidative activity with no stimulus and with formylmethionyl-leucyl-phenylalanine (FMLP) were analyzed as the priming index and FMLP response, respectively. Interleukin (IL)-6, IL-10, PMNL elastase, and thrombomodulin concentrations in blood were also measured before and after the second hit. RESULTS: The PMNL priming index was elevated from days 2 to 13, especially days 2 to 5 after injury. FMLP response was enhanced from days 2 to 21 after injury. Apoptosis of PMNL was inhibited for as long as 3 weeks after injury. Infections as second hits after trauma enhanced both the priming index and the FMLP response within 24 hours after diagnosis of infection and increased serum IL-6 concentrations. However, serum thrombomodulin levels were not affected by second hits. All patients with second hits survived. CONCLUSION: Severe trauma stimulated acute-phase priming in PMNL and inhibited apoptosis. Infections after trauma induced second-hit priming in PMNL, but the unchanged serum levels of thrombomodulin suggest that priming per se may not cause systemic vascular endothelial damage.

Adult↗
PubMed1999

Granulocyte colony-stimulating factor ameliorates life-threatening infections after combined therapy with barbiturates and mild hypothermia in patients with severe head injuries.

OBJECTIVE: The objective of this study was to clarify the effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) administration on infections in patients with severe head injuries after combined therapy with high-dose barbiturates and mild hypothermia. PATIENTS AND METHODS: Since 1996, we have administered rhG-CSF to eight patients with severe head injuries for 5 days (group G). Their treatment results were compared with those of 22 patients cared for earlier without rhG-CSF treatment (group N). All patients in both groups met the criteria of total leukocyte count (TLC) less than 5,000/mm3, C-reactive protein (CRP) over 10 mg/dL, and the presence of an infectious complication. Changes in the TLC, CRP, respiratory index, intracranial pressure, and infectious condition were evaluated in both groups. In addition, the nucleated cell count and differentiation from bone marrow aspiration, neutrophil functions, serum concentrations of interleukin-6, and plasma concentration of leukocyte elastase were evaluated in group G. RESULTS: In group G, TLC, nucleated cell count, and neutrophil functions significantly increased, whereas CRP, respiratory index, and interleukin-6 decreased reciprocally. There was no deterioration of intracranial pressure and leukocyte elastase. Consequently, seven of the eight patients in group G recovered from life-threatening infections, and none of the eight patients died. However, in group N, CRP and respiratory index remained high and TLC did not increase as much as it did in group G. Infections continued after 5 days in 17 of the 22 patients, 7 of whom died from severe infections during hospitalization. CONCLUSION: Administration of rhG-CSF ameliorated life-threatening infections without causing lung injury or increasing brain swelling in patients with severe head injuries who were treated with combined therapy involving high-dose barbiturates and mild hypothermia.

Adolescent↗
PubMed1999

Synthesis and antifungal activities of (2R,3R)-2-aryl-1-azolyl-3-(substituted amino)-2-butanol derivatives as topical antifungal agents.

2-Aryl-1-azolyl-3-(substituted amino)-2-butanol derivatives I were prepared by ring-opening reaction of epoxides II with excess amine, and their antifungal activities were evaluated as topical agents. Azolyl-cyclic amine derivatives with a methylene group showed extremely strong activity with a broad spectrum in vitro. In general, anti-Trichophyton mentagrophytes activities of most of the topical antifungal agents are substantially reduced by addition of keratin (a major constituent of the keratinized tissue). However, the triazole derivative (2R,3R)-2-(2,4-difluorophenyl)-3-(4-methylenepiperidino)-1-(1H-1,2 ,4- triazol-1-yl)-2-butanol ((-)-40, KP-103) showed very little deactivation by addition of keratin. This biological characteristic of triazole derivative (-)-40 resulted in excellent therapeutic efficacy on dermatophytosis superior to that of the corresponding imidazole derivative ((-)-41).

Animals↗
PubMed1999

[Discovery and development of donepezil hydrochloride for the treatment of Alzheimer's disease].

The most consistent change of neurotransmitter in the brain of Alzheimer's patients is the dramatic decrease of cholinergic innervation due to the loss of neurons in the basal forebrain. The most widely studied acetylcholinesterase inhibitors (AChEIs) have been physostigmine and tacrine. Physostigmine has very short duration, and tacrine has liability to hepatotoxicity. These are the defects of the inhibitors. Our objective was to find a new type of AChEIs that would overcome the disadvantages of physostigmine and tacrine. Through a random screening, we incidentally found an N-benzylpiperazine derivative which showed positive cholinergic behavior in rats. We replaced the N-benzylpiperazine moiety with N-benzylpiperidine moiety and found a dramatic increase in anti-AChE activity. Even after the replacement of an amide group with a ketone group the activity was held. Furthermore, the cyclic-amide derivative showed enhanced inhibitory activity. On the basis of these results, an indanone derivative was designed. Among these indanone derivatives, donepazil hydrochloride (E2020), brand name ARICEPT was found to be the most balanced compound. The clinical studies of donepezil hydrochloride demonstrated statistically significant effects on ADAS-cog (Alzheimer's Disease Assessment Scale cognitive sub.) and CIBIC Plus (Clinician's Interview-Based Impression of Change plus).

Acetylcholine↗
PubMed1999

Different transcriptional expression of the matrix gene of the two sibling viruses of the subacute sclerosing panencephalitis virus (Osaka-2 strain) isolated from a biopsy specimen of patient brain.

Two sibling viruses of the subacute sclerosing panencephalitis (SSPE) virus Osaka-2 strain were isolated from a small biopsy specimen of the brain of an SSPE patient just before intraventricular interferon treatment by cocultivation with two different cell lines, Vero cells or B95a cells (Ogura et al, 1997). Both the virus-infected cells were found to be indistinguishable from each other in defective production of cell-free virus and in defective expression of the matrix (M) protein. The sequence analysis of the M genes predicted that they were translatable due to a lack of alteration of the translational start and stop codons for the proteins. A different pattern of the M monocistronic transcripts, however, was observed in a Northern blot analysis of the infected cells. This different pattern was confirmed further by a primer extension analysis. The undetectable expressions of the M proteins in the sibling virus-infected cells are most probably different in their molecular mechanisms. All these results indicate the possibility that the two different, replicable variants existed at Jabbour stage III of the disease's progression in a very small portion of the brain, where no lesion had yet been recognized by a magnetic resonance imaging.

Amino Acid Sequence↗
PubMed1999

Human papillomavirus as a risk factor for head and neck cancers--a case-control study.

A retrospective, case-control study was conducted to examine the relationship between the presence of human papillomavirus types 16 and 18 (HPV16/18) DNA and the risk of head and neck cancers. Twelve out of 74 (16.2%) head and neck cancers contained HPV16/18 DNA, while 3 out of 70 (4.2%) non-cancer controls showed HPV16/18 positivity by polymerase chain reaction. The presence of HPV16/18 DNA was associated with an increased risk of head and neck cancer formation, showing an odds ratio of 4.32, with a 95% confidence interval of 1.26-14.78. Although its epidemiological impact might be smaller than that of other factors like cigarette smoking, the presence of HPV16/18 DNA in the aerodigestive tract is suggested to be a risk factor for human head and neck cancers.

Carcinoma, Squamous Cell↗
PubMed1998

Differential effects of the strychnine-insensitive glycine site antagonist (+)-HA-966 on the hyperactivity and the disruption of prepulse inhibition induced by phencyclidine in rats.

The amplitude of the acoustic startle response is reduced by a preceding weak stimulation which by itself does not elicit the startle response. This phenomenon is named prepulse inhibition (PPI) and is thought to reflect the operation of the sensorimotor gating system, which is deficient in schizophrenic patients. It has been reported that an antagonist at the strychnine-insensitive glycine site has atypical neuroleptic properties in experimental animals. To evaluate the effect of an antagonist at the site on disrupted PPI, we examined whether (+)-HA-966 antagonizes phencyclidine-induced (3 mg/kg s.c.) and apomorphine-induced (1 mg/kg s.c.) disruption of PPI in rats. In addition, its effect on phencyclidine-induced hyperactivity was tested. The effects of (+)-HA-966 were compared with those of haloperidol, a typical neuroleptic. (+)-HA-966 antagonized phencyclidine-induced hyperactivity, but not phencyclidine-induced disruption of PPI, which is thought to be a model of refractory symptoms in schizophrenia. Furthermore, (+)-HA-966 did not improve the deficit in PPI induced by apomorphine. On the other hand, haloperidol antagonized phencyclidine-induced hyperactivity and the disruption of PPI by apomorphine, but not by phencyclidine. The results of this study might mean that (+)-HA-966 antagonizes the behavioral change induced by excessive dopamine release (the increment of locomotor activity due to phencyclidine), but not the effect induced by a direct dopamine agonist or the dopamine-independent effect of phencyclidine (the disruption of PPI). Thus, as regards antagonism of phencyclidine-induced disruption of PPI, (+)-HA-966 does not appear to have an atypical neuroleptic-like effect.

Animals↗