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M Takeda

Publications and source records attributed to M Takeda.

At least 145 records · Page 8Linked to original sources
PubMed2000

Olfactory epithelium consisting of supporting cells and horizontal basal cells in the posterior nasal cavity of mice.

The olfactory epithelium of mice generally consists of olfactory cells, progenitors of olfactory cells (globose basal cells), supporting cells, and horizontal basal cells. However, in the dorsal fossa (the roof) of the posterior nasal cavity of mice, we found seven epithelial patches consisting of only non-neuronal cell types, i.e., supporting cells and horizontal basal cells, among the normal olfactory epithelium. The supporting cells occupied three or four layers in the apical to middle regions; in the basal region, horizontal basal cells were localized in a single row adjacent to the basement membrane. Bowman's gland ducts were also present in the epithelium. Neuronal cells (olfactory cells and globose basal cells) were totally absent. The ultrastructure of the supporting cells, horizontal basal cells, and Bowman's glands was essentially similar to that in the normal olfactory epithelium. In the early postnatal period (P1-P7), cell types in the epithelium were the same as those in the normal olfactory epithelium. From P10 to P21, olfactory cells and globose basal cells had disappeared from the olfactory epithelium. At this period, the number of TUNEL-positive cells was significantly higher than that in the surrounding olfactory epithelium; ultrastructurally, many apoptotic figures were observed. This suggests that the epithelium consisting of supporting cells and horizontal basal cells is generated by the apoptotic death of olfactory cells and globose basal cells during postnatal development.

Age Factors↗
PubMed2000

Heparin reduces serum levels of endothelin-1 and hepatic ischemia reperfusion injury in rabbits.

Since the role of heparin in hepatic ischemia/reperfusion (I/R) injury is still not fully understood, we investigated the effects of heparin on hepatic I/R injury in rabbits. Heparin was injected into rabbits after inducing partial hepatic ischemia for 1 h. Thereafter, the serum levels of endothelin-1 (ET-1) and liver transaminase, and tissue levels of oxidized and deoxidized hemoglobin (oxHb, deoxHb) in the reperfused liver were analyzed. Microscopic examinations were also performed. The increased serum levels of ET-1 and liver transaminase after reperfusion were significantly reduced by heparin (P > 0.01). Hepatic ischemia reduced oxHb and increased deoxHb. Reperfusion with heparin immediately reduced deoxHb and increased oxHb, and thereafter the balance between the two kinds of Hb also recovered. However, reperfusion without heparin did not demonstrate any similar recovery, but instead gradually exacerbated the dissociation. Microscopically, heparin appeared to normalize I/R-induced activation of hepatic stellate cells which are the target cells for ET-1. These results suggest that heparin improves the hepatic I/R injury caused by sinusoidal microscirculatory disturbances partly via an inhibition of the ET-1 increase.

Animals↗
PubMed2000

Systemic-to-pulmonary shunt in a patient with isolation of the subclavian artery.

A surgical procedure is described that was carried out to treat an 18-month-old boy with tetralogy of Fallot, right aortic arch, and isolation of the left subclavian artery. The patient underwent a descending aorta-right pulmonary artery shunt using a polytetrafluoroethylene graft, as a systemic-pulmonary shunt. The effectiveness of this procedure in patients with some special conditions is discussed.

Abnormalities, Multiple↗
PubMed2000

The neural basis of perceptual and conceptual word priming--a PET study.

Positron emission tomography scans were obtained in 13 normal subjects during perceptual and conceptual word priming tasks with the aim to investigate the neural system specific to the two priming conditions. In the prescan phase, subjects were primed perceptually or conceptually with two separate procedures, while in the scan phase, they performed the same stem completion task. Therefore we could compare the results of the two priming tasks in a direct manner. A fixation control task and a baseline task (completion of stems that did not correspond to previously seen words) were also given. A specific blood flow decrease was found in the left inferior temporal cortex in the perceptual word priming condition and in the left superior temporal / inferior parietal cortex in the conceptual word priming condition. Each blood flow change may reflect transient changes in the cortical areas subserving the processing of the perceptual and conceptual components of word priming.

Adult↗
PubMed2000

Preference for vegetable oils in the two-bottle choice test in mice.

We evaluated in mice their preference for different vegetable oils using the two-bottle choice test. Mice showed preference for all vegetable oils (at 1% concentration in emulsion) tested, including corn oil, canola oil, and mixed vegetable oil, compared to a control fluid without oil. Mice also significantly preferred highly palatable sucrose solutions (5-20%) in this test. One percent corn oil was selected to the same extent as were these sucrose solutions. Mixtures of 1% corn oil and several concentrations of sucrose were preferentially selected as compared to corn oil or sucrose alone. The concentration-response curves of oil-sucrose mixtures vs sucrose (0.5-20% concentrations) were similar to those of sucrose vs control solutions. These results suggest that 1% corn oil and sucrose at the concentrations tested did not affect each other's preference. Chronic intake of 20% sucrose solution, but not 100% corn oil, changed the preference for lower concentrations of each, and both induced remarkable increases in body weight of mice. In conclusion, we showed that mice preferred vegetable oils, and this preference compared favorably with highly palatable sucrose solutions and was not changed by chronic intake of corn oil.

Analysis of Variance↗
PubMed2000

Regulation by protein kinase C of organic anion transport driven by rat organic anion transporter 3 (rOAT3).

The organic anion transporter 3 (rOAT3) is a multispecific OAT localized at the basolateral membrane of the proximal tubule. The purpose of this study was to elucidate the role of protein kinase C (PKC) in the regulation of organic anion transport driven by rOAT3 and its mechanism of action. For this purpose, we established and utilized cells derived from the second segment of proximal tubule from mice stably expressing rOAT3 (S2 rOAT3). Phorbol 12-myristate 13-acetate (PMA), a PKC stimulator, attenuated the cellular uptake of estrone sulfate (ES), a prototype organic anion for rOAT3, in a dose- and time-dependent manner. PMA treatment resulted in a decrease in the Vmax, but not the Km of uptake of ES in S2 rOAT3. Treatment of S2 rOAT3 with other PKC stimulators or diacylglycerols also inhibited the uptake of ES, whereas that with an inactive phorbol ester did not. Chelerythrine chloride, a PKC inhibitor, reversed the PMA-induced decrease in uptake of ES in S2 rOAT3. These results suggest that PKC activation downregulates rOAT3-mediated organic anion transport. This down-regulation may be due to the inhibition of translocation or internalization of the rOAT3 protein, resulting in the decrease in the Vmax of rOAT3-mediated organic anion transport.

Animals↗
PubMed2000

Effects of ouabain and flecainide on CO(2)-induced slowly adapting pulmonary stretch receptor inhibition in the rabbit.

The inhibitory effect of CO2 on slowly adapting pulmonary stretch receptors (SARs) was examined before and after administration of ouabain, a Na+-K+ ATPase inhibitor, and flecainide, a Na+ channel blocker. The experiments were performed in anesthetized, artificially ventilated rabbits after vagus nerve section. CO2 inhalation (maximal tracheal CO2 concentration ranging from 9.2 % to 10.4%) for about 60 sec decreased the receptor activity during both inflation and deflation. The magnitude of decreased SAR activity during deflation was greater than that seen during inflation. Administration of ouabain (25 microg/kg) initially stimulated SAR activities during inflation and deflation, and after 20 min, the SAR response was still kept excitatory in both inflation and deflation phases. Under these conditions, CO2 inhalation inhibited SAR activities during inflation and deflation. Flecainide treatment (3 mg/kg) that abolished veratridine (30 microg/kg)-induced SAR excitation had no significant effect on the inhibitory responses of SAR activity to CO2. These results suggest that the inhibitory effect of CO2 occurs when ouabain results in intracellular Na+ concentration ([Na+]i) increases in the SAR endings, and that CO2-induced SAR inhibition may not be related to the reduction of influx of Na+ through voltage-gated Na+ channels.

Adaptation, Physiological↗
PubMed2000

Xenopus msx-1 regulates dorso-ventral axis formation by suppressing the expression of organizer genes.

We demonstrated previously that Xmsx-1 is involved in mesoderm patterning along the dorso-ventral axis, under the regulation of BMP-4 signaling. When Xmsx-1 RNA was injected into the dorsal blastomeres, a mass of muscle tissue formed instead of notochord. This activity was similar to that of Xwnt-8 reported previously. In this study, we investigated whether the activity of Xmsx-1 is related to the ventralizing signal and myogenesis promoting factor, Xwnt-8. Whole-mount in situ hybridization showed that Xmsx-1, Xwnt-8, and XmyoD were expressed in overlapping areas, including the ventro-lateral marginal zone at mid-gastrula stage. The expression of XmyoD was induced by the ectopic expression of either Xmsx-1 or Xwnt-8 in dorsal blastomeres, and Xwnt-8 was induced by the ectopic expression of Xmsx-1. On the other hand, the expression of Xmsx-1 was not affected by the loading of pCSKA-Xwnt-8 or dominant-negative Xwnt-8 (DN-Xwnt-8) RNA. In addition, Xmsx-1 RNA did not abrogate the formation of notochord if coinjected with DN-Xwnt-8 RNA. These results suggest that Xmsx-1 functions upstream of the Xwnt-8 signal. Furthermore, the antagonistic function of Xmsx-1 to the expression of organizer genes, such as Xlim-1 and goosecoid, was shown by in situ hybridization analysis and luciferase reporter assay using the goosecoid promoter construct. Finally if Xmsx-1/VP-16 fusion RNA, which was expected to function as a dominant-negative Xmsx-1, was injected into ventral blastomeres, a partial secondary axis formed in a significant number of embryos. In such embryos, the activity of luciferase, under the control of goosecoid promoter sequence, was significantly elevated at gastrula stage. These results led us to conclude that Xmsx-1 plays a central role in establishing dorso-ventral axis in gastrulating embryo, by suppressing the expression of organizer genes.

Actins↗
PubMed2000

Divergence of glyceraldehyde-3-phosphate dehydrogenase isozymes in Saccharomyces cerevisiae complex.

Although sake yeasts are placed in Saccharomyces cerevisiae, we have been interested in their difference from the other subgroups of the species, and examined their proteins. When SDS-PAGE patterns of their soluble proteins were compared, specific differences between subgroups were found in their 36,000 Da regions. Proteins isolated therefrom were found to be subunits of three isomers of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from their N-terminal amino acid sequences and identified with anti-GAPDH serum. Therefore, comparison of zymogram was carried out by a modified method: denatured monomers were observed and the enzyme activity of their oligomers was not considered. SDS-PAGE patterns of all the sake yeasts differed from those of the other strains of S. cerevisiae. Strains of Saccharomyces bayanus showed uniform patterns which are different from the above two groups. Saccharomyces pastorianus strains resembled S. bayanus and were partly similar to S. cerevisiae in their patterns, in agreement with the hypothesis that S. pastorianus is a hybrid between these two species. Patterns of S. paradoxus appeared to be rather similar to those of sake yeasts. Results on the other species of the genus and on the preliminary experiments on PAGE of native isozymes are also described.

Alcoholic Beverages↗
PubMed2000

Laparoscopic adrenalectomy: transperitoneal vs retroperitoneal approaches.

PURPOSE: To compare the results between transperitoneal and retroperitoneal approaches. MATERIALS: Between 17 January 1992 and 31 December 1997, 76 patients (31 men and 45 women, 37 right and 37 left, mean 46.7 years old) with adrenal tumors including 37 primary aldosteronism. 19 Cushing's syndrome, 15 non-functioning adrenal tumors, and five pheochromocytomas, underwent laparoscopic removal operations in one hospital. Fifty-seven open adrenalectomies were also included. METHODS: Fifty-two patients by transperitoneal laparoscopic approach, and the other 24 patients by retroperitoneal laparoscopic approach were compared. RESULTS: Mean operative time, operative blood loss, time to oral intake, and ambulation of transperitoneal approach were 203 min, 115.6 mL, 1.9 days, and 1.4 days. In patients operated on by the retroperitoneal approach, these factors were 257 min, 141.6 mL, 1.1 days, and 1.4 days. There was no significant difference in any item between the two groups. In patients operated on by open procedure, these factors were 143 min, 214 mL, 2.5 days, and 2.4 days. Operating time of the open surgery group was significantly shorter than either of the other two groups, and all of the other three items of open surgery group were significantly greater than either of the other two groups. Open surgery was required in two of 76 patients treated by endoscopic procedure due to inadvertent injury of the anomalous adrenal vein during the transperitoneal approach, and pancreatic injury during the retroperitoneal approach. During and after the operation, no significant complication was observed. CONCLUSION: Both transperitoneal and retroperitoneal laparoscopic adrenalectomies are feasible for adrenal tumors.

Adrenal Gland Neoplasms↗
PubMed2000

Complications of laparoscopic and retroperitoneoscopic adrenalectomies in 370 cases in Japan: a multi-institutional study.

A total of 370 laparoscopic adrenalectomies, including 311 transperitoneal (TP) and 59 retroperitoneal (RP) approaches, were performed in nine urologic centers, where the laparoscopic adrenalectomy was first begun independently in Japan, and their affiliated hospitals between January 1992 and September 1996. The clinical diagnoses of those 370 adrenal diseases were primary aldosteronism in 155 patients, Cushing's syndrome in 61. preclinical Cushing's syndrome in 21. pheochromocytoma in 16, nonfunctioning adenoma in 87, complicated cyst in ten, myelolipoma in nine, adrenal cancer in four and other diagnoses in eight (table 1). There was no mortality in this series. Intraoperative complication rate was 33/370 (9%) in total: 26/311(8%) in the TP procedures and 7/59 (12%) in the RP procedures (table 11). Postoperative complication rate was 24/370 (6%) in total: 22/311 (7%) in the TP procedures and 2/59 (3%) in the RP ones (table 111). Conversion rates to open surgery in total, in the TP and in the RP procedures were 13/370 (3.5%), 10/311 (3.2%) and 3/59 (5.1 %). respectively (table IV). Although the RP procedure has a lower morbidity rate compared to the TP procedure, more skill is required to overcome the drawback of the narrow working space and fewer anatomical landmarks.

Adenoma↗
PubMed2000

Molecular identification and pharmacological characterization of adenosine receptors in the guinea-pig colon.

The aim of this study is to elucidate the role of adenosine in the motor function of the guinea-pig distal colon.2 To determine whether adenosine A(1) receptors and A(2B) receptors are expressed in the guinea-pig colon, we employed the reverse transcription-polymerase chain reaction (RT - PCR). The gene expression of A(1) receptor and A(2B) receptor was found for the first time in the guinea-pig proximal and distal colon.3 Adenosine A(1) agonist N(6)-cyclopentyladenosine (CPA), and A(1)/A(2) agonist 5'-N-ethylcarboxamidoadenosine (NECA) concentration-dependently inhibited neurogenic responses to electrical field stimulation (EC(50)=1.07x10(-8) and 2.12x10(-8) M) in the longitudinal muscle, but A(2A) agonist 2-p-(2-carboxyethyl)phenylethylamino-5'-N-ethycarboxamido-ad enosine (CGS21680) had only a slight inhibitory effect (25.9%, 1 microM). A(1) antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 10 nM: A(1) selective concentration) antagonized responses to CPA and NECA. Furthermore, the affinity order of antagonists at inhibiting the effect NECA was: DPCPX>8-phenyltheophylline (8-PT: A(1)/A(2) antagonist).3 In the presence of tetrodotoxin (TTX, 0.3 microM), CPA and NECA relaxed myogenic precontraction induced by KCl (50 mM) (EC(50)=1.26x10(-5) and 1.04x10(-5) M, respectively), but CGS21680 (1 microM) did not cause any relaxation. DPCPX did not affect responses to CPA and NECA at a concentration of 10 nM, but a higher concentration (1 microM) of DPCPX and 10 microM of 8-PT antagonized those responses.5 These data lead us to the hypothesis that adenosine may mediate relaxation through two different inhibitory receptor subtypes; A(1) receptors on the enteric neuron and A(2B) receptor on the smooth muscle in the guinea-pig distal colon.

Acetylcholine↗
PubMed2000

Potential mechanisms of resistance to TRAIL/Apo2L-induced apoptosis in human promyelocytic leukemia HL-60 cells during granulocytic differentiation.

Human promyelocytic leukemia HL-60 cells are well known to differentiate into granulocytes or monocytes in the presence of some agents such as DMSO or PMA, respectively. Differentiated HL-60 cells become resistant to some apoptotic stimuli including anticancer drugs or irradiation though undifferentiated cells significantly respond to these stimuli. TRAIL (TNF-related apoptosis-inducing ligand) which is also known as Apo2 ligand (Apo2L), a new member of TNF family, can induce apoptosis in some tumor cells but not in many normal cells. We show here that apoptosis is well induced in HL-60 cells by TRAIL, but susceptibility to TRAIL is reduced during granulocytic differentiation by DMSO. We also suggest some possible mechanisms by which granulocytic differentiated cells become resistant to TRAIL-induced apoptosis. First, in granulocytic differentiated cells, expression of antagonistic decoy receptors for TRAIL (TRAIL-R3/TRID/DcR1/LIT and TRAIL-R4/TRUNDD/DcR2) were enhanced. In addition, expression of Toso, a cell surface apoptosis regulator, seemed to block activation of caspase-8 by TRAIL via enhanced expression of FLIPL in granulocytic differentiated cells. These findings suggest that differentiated cells are resistant using plural mechanisms against various apoptosis-inducing stimuli rather than undifferentiated cells.

Apoptosis↗
PubMed2000

Localized phosphorylation of vimentin by rho-kinase in neuroblastoma N2a cells.

BACKGROUND: Vimentin, which is one of the intermediate filaments, is the major cytoskeletal component in developing neurones or neuroblastoma cells. Rho-associated kinase (Rho-kinase), is rich in neurones and is found downstream of Rho. It is involved in the agonist-induced neurite retraction of neuronal cells, and phosphorylates vimentin at Ser-38 and Ser-71 resulting in in vitro disassembly of the filaments. RESULTS: We have investigated the distribution of vimentin phosphorylated by Rho-kinase in N2a neuroblastoma cells using site-specific phosphorylation-dependent antibodies. TM71 immunoreactivity, which specifically indicates Ser-71 phosphorylation on vimentin, was found in some neurites of dibutyryl cAMP-differentiated N2a cells. Transfection of the constitutively active form of Rho-kinase, CAT, significantly elevated TM71 immunoreactivity, and induced neurite retraction or cell rounding. Conversely, transfection of the dominant negative form of Rho-kinase, RB/PH(TT), or treatment of 10 microM Y-27632, a Rho-kinase specific inhibitor, abolished TM71 immuno-reactivity, and induced irregular neurite outgrowth. In contrast, 20 nM okadaic acid (OA) induced neurite retraction and specifically elevated TM71 immunoreactivity. In the OA-induced neurite retraction, tubulin disappeared in retracting neurites, where vimentin and actin remained co-localized. Furthermore, the OA-induced elevation of TM71 immunoreactivity and neurite retraction were completely blocked by pretreatment with 10 microM Y-27632, or by the ectopic expression of RB/PH(TT). CONCLUSIONS: This study suggests that the localized phosphorylation of vimentin by Rho-kinase in neurites was closely related with the cellular morphology of N2a cells, and that the Rho-kinase activity towards vimentin was balanced with OA-sensitive phosphatases.

Amides↗
PubMed2000

Involvement of BMP-4/msx-1 and FGF pathways in neural induction in the Xenopus embryo.

The msx homeodomain protein is a downstream transcription factor of the bone morphogenetic protein (BMP)-4 signal and a key regulator for neural tissue differentiation. Xmsx-1 antagonizes the dorsal expression of noggin and cerberus, as revealed by in situ hybridization and reverse transcription-polymerase chain reaction assays. In animal cap explants, Xmsx-1 and BMP-4 inhibit the neural tissue differentiation induced by noggin or cerberus. A loss-of-function study using the Xmsx-1/VP-16 fusion construct indicated that neural tissue formation was directly induced by the injection of fusion ribonucleic acid, although the expression of neural cell adhesion molecule (N-CAM) in the cap was less than that in the cap injected with tBR or noggin. In contrast to the single cap assay, unexpectedly, both BMP-4 and Xmsx-1 failed to inhibit neurulation in the ectodermal explants to which the organizer mesoderm was attached. The results of cell-lineage tracing experiments indicated that the neural cells were differentiated from the animal pole tissue where the excess RNA of either BMP-4 or Xmsx-1 was injected, whereas notochord was differentiated from the organizer mesoderm. Neural tissue differentiated from BMP-4-injected ectodermal cells strongly expressed posterior neural markers, such as hoxB9 and krox20, suggesting that the posterior neural cells differentiated regardless of the existence of the BMP signal. The introduction of a dominant-negative form of the fibroblast growth factor (FGF) receptor (XFD) into the ectodermal cells drastically reduced the expression of pan and posterior neural markers (N-CAM and hoxB-9) if co-injected with BMP-4 RNA, although XFD alone at the same dose did not shut down the expression of N-CAM in the combination explants. Therefore, it is proposed that an FGF-related molecule was involved in the direct induction of posterior neural tissue in the inducing signals from the organizer mesoderm in vivo.

Animals↗
PubMed2000

An empirical classification of social anxiety: performance, interpersonal and offensive.

This study empirically identified subtypes of social anxiety using a cluster analytic approach. From 87 out-patients with social phobia (taijin kyofusho) and 48 controls, social anxiety symptoms, social situations in which symptoms occur, and background information were evaluated. Factor analysis using the ratings of social anxiety symptoms identified four factors: socially inadequate feelings, performance anxiety, offensive fear, and tenacity. Four subtypes emerged from cluster analysis based on the factor scores and they were called performance anxiety type, offensive type, interpersonal anxiety type and mild type. Chi2 test and analysis of variance revealed the following: (i) the offensive type had the greatest symptom severity. Any situation could provoke symptoms, and interpersonal tense feelings became much stronger with persons of the same age; (ii) the interpersonal anxiety type was characterized by the fear of social interaction in daily life; and (iii) patients with the offensive type and the interpersonal anxiety type presented more difficulties than did those with the performance anxiety type on developmental and premorbid adjustment.

Adult↗
PubMed2000

The influences of family environment on personality traits.

In order to clarify the influences of family environment on the development of personality traits, 150 children (104 males and 46 females, mean age 13.2 +/- 2.4 years) who had been interviewed at the Child Guidance Clinic in Osaka were investigated. From 13 behavioral characteristics (activity, talkativeness, sociability, social skills, rule-keeping, will, aggression, emotional control, imagination, anxiety, maturity, intelligence, and neuroticism), factor analysis identified three personality traits: extraversion, maturity, and intellect. The effects of family environment (maternal and paternal participation in child rearing before and after 4years of age, child-rearing style, parental relationship, sibling relationship, number of siblings, birth order, and socioeconomic status) on these personality traits were examined based on a structural equation model. The results found, first, that extraversion was negatively associated with overprotection/interference and with maternal participation in child rearing. Maturity correlated with high socioeconomic status, appropriate child-rearing style, and paternal participation in child rearing. Intellect was related to high socioeconomic status and maternal participation in child rearing. Second, path analysis with selected variables revealed that 8% of variance in extraversion, 14% in maturity, and 10% in intellect was due to family environment. Third, children with high introversion or high intellect had stronger influences from family environment than did those with high extraversion or low intellect.

Adolescent↗