Biomedical subjects

H Ochiai

Publications and source records attributed to H Ochiai.

At least 55 records · Page 3Linked to original sources

PubMed1999

Inhibitory effect of Ephedrae herba, an oriental traditional medicine, on the growth of influenza A/PR/8 virus in MDCK cells.

Using several herbal extracts, we investigated whether certain Kampo medicines exert an inhibitory effect on the acidification of intracellular compartments such as endosomes and lysosomes (referred to as ELS), and thereby inhibit the growth of influenza A virus in Madin-Darby canine kidney cells. The vital fluorescence microscopic study showed that the extract of Ephedrae herba (EHext) among five herbal extracts inhibited acidification of endosomes and lysosomes in a concentration-dependent manner (100-400 microg/ml). Moreover the growth of influenza A/PR/8/34 (H1N1) (PR8) virus was inhibited when the cells were treated with EHext for 1 h immediately after infection, or treated as early as 5-10 min after infection. Conversely, virus growth resumed concomitantly with the reappearance of acidified ELS after removal of EHext. The fact that the inhibitory effect of EHext was completely or partially reversed by FeCl3, a tannin-reactive agent, strongly suggests that tannin is one of the active components in the extract.

Animals↗

PubMed1999

Promoter analysis of the membrane protein gp64 gene of the cellular slime mold Polysphondylium pallidum.

We cloned a genomic fragment of the membrane protein gp64 gene of the cellular slime mold Polysphondylium pallidum by inverse PCR. Primer extension analysis identified a major transcription start site 65 bp upstream of the translation start codon. The promoter region of the gp64 gene contains sequences homologous to a TATA box at position -47 to -37 and to an initiator (Inr, PyPyCAPyPyPyPy) at position -3 to +5 from the transcription start site. Successively truncated segments of the promoter were tested for their ability to drive expression of the beta-galactosidase reporter gene in transformed cells; also the difference in activity between growth conditions was compared. The results indicated that there are two positive vegetative regulatory elements extending between -187 and -62 bp from the transcription start site of the gp64 promoter; also their activity was two to three times higher in the cells grown with bacteria in shaken suspension than in the cells grown in an axenic medium.

Animals↗

PubMed1999

The neurotensinergic synaptic innervation of vasopressin containing neurons in the rat hypothalamic paraventricular nucleus.

A recent physiological report suggested that neurotensin could inhibit the vasopressin releasing from vasopressin-producing neurons in the hypothalamic paraventricular nucleus but not in the supraoptic nucleus. In the present study, the synaptic relationship between the neurotensin-like immunoreactive and vasopressin-like immunoreactive neurons has been examined using a pre-embedding double immunostaining technique in the rat hypothalamic paraventricular nucleus. At the light microscopic level, many neurotensin-like immunoreactive fibers were found near the vasopressin-like immunoreactive neurons. At the electron microscopic level, the neurotensin-like immunoreactive fibers were identified as axon terminals that made many synapses on the vasopressin-like immunoreactive perikarya and dendrites. The synapses were both asymmetrical and symmetrical. These findings of the present study suggest that the inhibitory effect of neurotensin on the vasopressin neurons in the hypothalamic paraventricular nucleus may be due to the direct synapses made by neurotensin-like immunoreactive axon terminals on the vasopressin-like immunoreactive neurons.

Animals↗

PubMed1999

Double cancer of the gallbladder and common bile duct associated with an anomalous pancreaticobiliary ductal junction without a choledochal cyst: report of a case.

We report herein the case of a 37-year-old woman found to have double cancer of the gallbladder and common bile duct associated with an anomalous pancreaticobiliary ductal junction (APBDJ) without a choledochal cyst (CC). Abdominal ultrasonography showed an isoechoic mass in the gallbladder, and percutaneous transhepatic biliary drainage tubography revealed incomplete obstruction in the upper portion of the common bile duct and APBDJ. The patient underwent cholecystectomy, partial hepatic resection, pancreatoduodenectomy, and portal vein reconstruction. Pathological examination of the tumors from the gallbladder and bile duct revealed papillary carcinoma and poorly differentiated adenocarcinoma, respectively, and direct continuity was not observed between the tumors. A review of the literature on six cases of multiple primary carcinoma of the biliary tract associated with APBDJ without CC is presented following this case report. Double cancer of the biliary tract was found synchronously in five patients and metachronously in one. Gallbladder cancer showed subserosal invasion in four patients, while bile duct cancer invaded the pancreas in one patient and reached the serosa in two patients. Considering the potential for cancer to arise in the biliary tract and the difficulties associated with monitoring it, cholecystectomy and resection of the extrahepatic common bile duct may be the most appropriate treatment for patients with an APBDJ without a CC.

Adenocarcinoma↗

PubMed1999

Identification of Delta5-fatty acid desaturase from the cellular slime mold dictyostelium discoideum.

cDNA fragments putatively encoding amino acid sequences characteristic of the fatty acid desaturase were obtained using expressed sequence tag (EST) information of the Dictyostelium cDNA project. Using this sequence, we have determined the cDNA sequence and genomic sequence of a desaturase. The cloned cDNA is 1489 nucleotides long and the deduced amino acid sequence comprised 464 amino acid residues containing an N-terminal cytochrome b5 domain. The whole sequence was 38.6% identical to the initially identified Delta5-desaturase of Mortierella alpina. We have confirmed its function as Delta5-desaturase by over expression mutation in D. discoideum and also the gain of function mutation in the yeast Saccharomyces cerevisiae. Analysis of the lipids from transformed D. discoideum and yeast demonstrated the accumulation of Delta5-desaturated products. This is the first report concering fatty acid desaturase in cellular slime molds.

Amino Acid Sequence↗

PubMed1999

Killer-cell inhibitory receptors, CD158a/b, are upregulated by interleukin-2, but not interferon-gamma or interleukin-4.

Although it is now accepted that killer-cell inhibitory receptors (KIRs), which were molecularly cloned in 1995, deliver negative signals to natural killer (NK) cells regarding the recognition of target cells, it is still unclear how the expression of these receptors on lymphocytes is regulated. Therefore, we investigated the regulation of expression of representative KIRs, CD158a and CD158b, by cytokines such as interleukin-2 (IL-2), IL-4 and interferon-gamma (IFN-gamma). Neither IL-4 nor IFN-gamma affected the expression of CD158a/b, but incubation for 48 h with IL-2, which enhances the killer activity of NK cells, upregulated the expression of the KIRs. This upregulation by IL-2 was also observed in CD16-positive cells sorted from total lymphocytes. In contrast, IL-4, which is a down-regulator of IL-2-induced killer responses, did not change the level of CD158a/b expression when added after the IL-2 treatment. These findings suggest that IL-2 plays an important role in the regulation of CD158a/b expression, and might be involved in controlling NK activity via regulating expression of these molecules.

Cells, Cultured↗

PubMed1999

Inhibitory effect of ferulic acid and isoferulic acid on the production of macrophage inflammatory protein-2 in response to respiratory syncytial virus infection in RAW264.7 cells.

We investigated the effect of ferulic acid (FA) and isoferulic acid (IFA), which are the main active components of the rhizoma of Cimicifuga heracleifolia (CH), an anti-inflammatory drug used frequently in Japanese traditional medicine, on the production of macrophage inflammatory protein-2 (MIR-2) in a murine macrophage cell line, RAW264.7, in response to respiratory syncytial virus (RSV) infection. Following the exposure of cells to RSV for 20h, the MIP-2 level in condition medium was increased to about 20 ng/ml, although this level in mock-infected cells was negligible. In the presence of either FA or IFA, RSV-infected cells reduced MIP-2 production in a dose-dependent manner. These data suggest that FA and IFA might be responsible, at least in part, for the anti-inflammatory drug effect of CH extract through the inhibition of MIP-2 production.

Animals↗

PubMed1999

Angiotensinogen gene polymorphism near transcription start site and blood pressure: role of a T-to-C transition at intron I.

Molecular variants of the angiotensinogen gene, a key component of the renin-angiotensin system, are considered genetic risk factors for primary hypertension. A relation between the angiotensinogen gene locus and hypertension has been found in whites, Japanese, and African Caribbeans but not in Chinese. The lack of a consistent association between M235T polymorphism at exon 2 and hypertension has suggested that another site in linkage disequilibrium with M235T is the causal mutation. We studied the relations among plasma angiotensinogen concentrations, blood pressure, related clinical variables, and mutations of the 5' upstream core promoter region of the human angiotensinogen gene in 274 subjects recruited from our outpatient clinic. We confirmed that plasma angiotensinogen concentration was significantly correlated with A-20C mutation and percent body fat and found that systolic and diastolic blood pressures were significantly correlated with G-6A and T+68C mutations. These results suggest that mutations near the transcription start site may be associated with increased blood pressure.

Angiotensinogen↗

PubMed1999

Neuroimaging of a wooden foreign body retained for 5 months in the temporalis muscle following penetrating trauma with a chopstick--case report.

A 48-year-old female was stabbed by her husband with a chopstick made of wood in the left temporal region during a quarrel. She suffered laceration of the left temporal scalp. At initial examination, she concealed the assault with a chopstick. Radiography showed no abnormality, so the wound was sutured. One month after the injury, a painless subcutaneous mass appeared in the left temporal region which grew rapidly for 3 months. She was then admitted to our department. Computed tomography (CT) on admission showed a hyperdense area at the center of the mass. This area was hypointense on both T1- and T2-weighted magnetic resonance (MR) images. Temporalis muscle tumor with accompanying central necrosis, old hematoma, and inflammatory granuloma was considered. The mass was totally resected for cosmetic purposes and was found to be wooden foreign body granuloma. High density on CT and hypointensity on both T1- and T2-weighted MR images are characteristic of a chronically retained wooden foreign body in the living body and are useful for detecting wooden foreign bodies in the chronic granulomatous phase.

Chronic Disease↗

PubMed1998

The Dictyostelium developmental cDNA project: generation and analysis of expressed sequence tags from the first-finger stage of development.

In an effort to identify and characterize genes expressed during multicellular development ill Dictyostelium, we have undertaken a cDNA sequencing project. Using size-fractionated subsets of cDNA from the first finger stage, two sets of gridded libraries were constructed for cDNA sequencing. One, library S, consisting of 9984 clones, carries relatively short inserts, and the other, library L, which consists of 8448 clones, has longer inserts. We sequenced all the selected clones in library S from their 3'-ends, and this generated 3093 non-redundant, expressed sequence tags (ESTs). Among them, 246 ESTs hit known Dictyostelium genes and 910 showed significant similarity to genes of Dictyostelium and other organisms. For library L, 1132 clones were randomly sequenced and 471 non-redundant ESTs were obtained. In combination, the ESTs from the two libraries represent approximately 40% of genes expressed in late development, assuming that the non-redundant ESTs correspond to independent genes. They will provide a useful resource for investigating the genetic networks that regulate multicellular development of this organism.

Animals↗

PubMed1998

Determination of montelukast sodium in human plasma by column-switching high-performance liquid chromatography with fluorescence detection.

MK-0476 (montelukast sodium) is a potent and selective cysteinyl leukotriene receptor antagonist that is being investigated in the treatment of asthma. A simple and sensitive method for the determination of MK-0476 in human plasma was developed using column-switching high-performance liquid chromatography (HPLC) with fluorescence detection. A plasma sample was injected directly onto the HPLC system consisting of a pre-column (Capcell pak MF) and an analytical column (Capcell pak C18) which were connected with a six-port switching valve. The column eluate was monitored with a fluorescence detector (excitation at 350 nm; emission at 400 nm). The calibration curve was linear in a concentration range of 1-500 ng ml(-1) for MK-0476 in human plasma. The intra-day coefficients of variation of all concentrations within the range was less than 9.2%, and the intra-day accuracy values were between 97.2 and 114.6%. This method was used to measure the plasma concentration of MK-0476 following oral administration of the drug in humans.

Acetates↗

PubMed1998

gp130 is involved in stretch-induced MAP kinase activation in cardiac myocytes.

We have recently reported that mitogen activated protein kinase (MAP kinase) is activated by the stretch of the cultured cardiac myocytes in the angiotensin II deficient state in the angiotensinogen-deficient mice (Atg-/-), suggesting that factors other than the cardiac renin-angiotensin system are involved in the stretch-induced MAP kinase activation. We examined the contribution of cytokines using RX435, an anti-gp130 antibody. Leukemia inhibitory factor, which is one of the cytokines and has the common receptor subunit gp130, activated MAP kinase and the response was completely blocked by pretreatment of the Atg-/- cardiac myocytes with RX435. RX435 pretreatment greatly reduced stretch-induced activation of MAP kinase in Atg-/- cardiac myocytes. Interestingly, the same results were obtained in the cardiac myocytes of control mice. These results suggest that cytokine-gp130 may play a role in the stretch-induced MAP kinase activation independently of Ang II in cardiac myocytes.

Angiotensinogen↗

PubMed1998

Ultrastructural localization of mu-1 opioid receptor in the dorsal raphe nucleus of the rat.

A simple pre-embedding avidin-biotin-peroxidase complex technique was used to study the ultrastructural localization of mu-1 opioid receptor in the rat dorsal raphe nucleus. Using low concentrations of the first antiserum for incubation with a short reaction time to 3,3'-diaminobenzidine, the immunostaining was faint at the light microscopic level. However, at the electron microscopic level strong immunoreaction was observed. Mu-1 opioid receptors were found to be localized on the postsynaptic membrane of dendrites, extra-synaptic plasma membrane, and the surface of the small, clear vesicles in axon terminals. Of the total 407 immunopositive profiles observed, 76.4% (311/407) were dendrites and 18.9% (77/407) were axon terminals. The immunostained myelinated axons and perikarya were relatively rare, with frequencies of 1.0% (4/407) and 3.7% (15/407), respectively. About 50.8% of the immunopositive dendrites (158/311) were immunostained having their MOR-LI results beneath the postsynaptic membrane, although about 19.6% of them (31/158) also exhibited MOR-LI on other components, including the extrasynaptic plasma membrane. Other immunopositive dendrites showed staining in some other contents, including extrasynaptic plasma membrane (82/311, 26.4%) or not on the plasma membranes (71/311, 22.8%). Less than half of the immunopositive axon terminals (35/77, 45.5%) were found to make synapses with nonimmunoreactive dendrites (31/77, 40.3%) or immunopositive dendrites (4/77, 5.2%); none were found to make synapses with immunoreactive perikarya. The present study shows that mu-1 opioid receptor in the dorsal raphe nucleus plays a role at both synapse or not.

Animals↗

PubMed1998

Distribution of PNP 14 (beta-synuclein) in neuroendocrine tissues: localization in Sertoli cells.

Phosphoneuroprotein (PNP 14) is abundant in the central nervous system and is localized at nerve endings but not in synaptic vesicles. In this study, we examined the presence of PNP 14 in various endocrine tissues of the rat. PNP 14 was not detected in the endocrine cells of the intestine, testes, or adrenal gland, but it was present in axon terminals in both the medulla of the adrenal gland and the anterior pituitary gland. When testes were stained with PNP 14-specific antibodies by an indirect immunofluorescence method, PNP 14 was found in Sertoli cells of the testes, associated with fibrillar structures. PNP 14 was also detected in cultured Sertoli cells with a fibrillar pattern in the cytoplasm and around the nuclei. The fibrillar structure did not resemble actin stress fibers, microtubules, or intermediate filaments. The amount of PNP 14 in the testis changed with development. It increased markedly during the first 4 weeks after birth and then decreased. During the first 4 weeks after birth, spermatogonia undergo two rounds of meiosis. It is possible, therefore, that PNP 14 might be a factor related to meiosis.

Animals↗

PubMed1998

Primary dissection of the hepatic artery: report of a case.

Dissecting aneurysms of the hepatic artery are extremely rare. We report herein the case of a 51-year-old man with massive hepatic metastases from rectal carcinoma, who was found incidentally to have a left hepatic artery aneurysm by a preoperative angiography. After replacing the left hepatic artery with a 2-cm segment of long saphenous vein, an extended right lobectomy with partial resection of the left lateral segment for multiple metastases was successfully performed. To prevent thrombus formation at the anastomosis, the Pringle maneuver was not used during dissection of the hepatic parenchyma. Histological examination of the resected specimen showed a dissecting aneurysm of the left hepatic artery, but there were no findings to suggest the etiology of this disease. The patient is currently alive 13 months after his operation without any evidence of further recurrence of the carcinoma. To the best our knowledge, 12 case reports of this anomaly have been documented, but only one of these describes a successful operation. The clinical features and etiology of the hepatic artery aneurysm that develops independent of other vascular diseases are discussed following this case report.

Aortic Dissection↗

PubMed1998

Analysis of peripheral blood mononuclear cell stimulated with pyruvate dehydrogenase complex, T-cell receptors from patients with primary biliary cirrhosis.

Progressive destruction of the intrahepatic bile ducts in patients with primary biliary cirrhosis (PBC) is thought to be mediated by cytotoxic T cells which recognize certain epitopes, such as the pyruvate dehydrogenase complex (PDC). To clarify the T-cell repertoire in PBC, we analyzed T-cell receptor (TCR) Vbeta-chain messages expressed in peripheral blood mononuclear cells (PBMCs) stimulated with PDC and in liver biopsy specimens. PBMCs from 12 PBC patients and 6 healthy controls were examined. The TCR Vbeta repertoires of unstimulated PBMCs and PBMCs stimulated with PDC purified from bovine heart were analyzed, using the reverse transcriptase-polymerase chain reaction (RT-PCR) and single-strand conformation polymorphism (SSCP). Liver biopsy specimens from 5 PBC patients were also analyzed. In the PBC patients, several different T-cell clones, some of which showed the same mobility, were evident in both the PDC-stimulated and unstimulated PBMCs, as demonstrated by SSCP analysis. In addition, TCR clonality of infiltrating lymphocytes in the liver was also observed in PBC patients, showing common clonal T-cell accumulation with that seen in PBMCs stimulated with PDC. These data indicate that common clonal T-cell accumulation specific for PDC may be present in both peripheral PBMCs and the liver of patients with PBC.

Case-Control Studies↗

PubMed1998

Fatty acid composition of the cellular slime mold Polysphondylium pallidum.

The cellular slime mold Polysphondylium pallidum was grown upon Escherichia coli B/r, and the fatty acid compositions of total lipids obtained from vegetative amebae and aggregation-competent cells were compared. Fatty acids isolated from vegetative cells included C-17 and C-19 cyclopropane fatty acids and also straight-chain, saturated fatty acids. The cyclopropane fatty acids were derived from the ingested bacteria. Development of amebae to aggregation-competent cells was accompanied by a substantial decrease in saturated cyclopropane fatty acids and a concomitant increase in unsaturated fatty acids and unsaturated cyclopropane fatty acids, mostly as 18:3 (5,9,12). We report here the fatty acid composition and identify the occurrence of delta 5 desaturation of cyclopropane fatty acids, namely, 9,10-methylene 5-hexadecenoic acid and 11,12-methylene 5-octadecenoic acid. These fatty acids have not been reported previously in the related species Dictyostelium discoideum, which also feeds on E. coli B/r and has delta 5-desaturation activity.

Chromatography, Gas↗

PubMed1998

Fos protein induction in the medullary dorsal horn and first segment of the spinal cord by tooth-pulp stimulation in cats.

Electrophysiological studies using the single neuron recording technique have led to the hypothesis that nociceptive neurons in the medullary dorsal horn (MDH) and the first segment of the spinal cord (C1) encode the stimulus intensity of noxious stimuli applied to the tooth pulp. The present study utilized the Fos protein technique in combination with electrical and chemical stimulation of the tooth pulp to test this hypothesis. Upper canine tooth-pulp stimulation with intensities just above the threshold stimulus intensity for evoking the jaw-opening reflex (JOR) did not produce a clear expression of Fos protein-like immunoreactive (LI) cells in the MDH and C1 of cats. Fos protein-LI cells were mainly found in the superficial laminae (laminae I-II) of the MDH and C1 after tooth-pulp stimulation of 200% of the JOR threshold intensity. When higher intensities (400-600% of the JOR threshold intensity) or mustard oil were applied, Fos protein-LI cells were also found in laminae III-IV as well as in laminae I-II. The number of Fos protein-LI cells significantly increased when 600% of the JOR threshold intensity or mustard oil was applied. Furthermore, the rostro-caudal distribution of Fos protein-LI cells was greater following increases in stimulus intensities and the greatest after mustard oil application. These data suggest that the change in number and spatial arrangement of nociceptive neurons in the MDH and C1 reflect changes in the encoding of the stimulus intensity applied to the tooth pulp.

Animals↗