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M Aihara

Publications and source records attributed to M Aihara.

At least 55 records · Page 3Linked to original sources
PubMed1999

Effects of isoproterenol on IL-2 and cAMP production in peripheral T cells from asthmatic and non-asthmatic subjects sensitive to Candida.

Immunity to Candida albicans (Candida) is characterized by a Th-1 type pattern of reactivity. Candida is rarely a cause antigen for bronchial asthma. Beta agonists have been found to inhibit secretion of IL-2 from T cells through intracellular cAMP elevation. We examined effects of isoproterenol (ISO) on Candida-stimulated T cells. Peripheral T cells obtained from six Candida-sensitive asthmatics, six Candida-sensitive non-asthmatic subjects, and six normal donors by Ficoll-Hypaque gradient centrifugation and nylon-wool column chromatography were incubated with Candida antigen or concanavalin A (Con A) in the absence or presence of ISO. Secretion of IL-2 and intracellular accumulation of cAMP were assayed by ELISA. Con A induced secretion of IL-2 in each of the three groups. Candida antigen induced IL-2 secretion in the normal and the non-asthmatic subjects, but not in the asthmatics. ISO, which reduced Con A-induced secretion of IL-2 in a dose-dependent manner, had no effect on Candida-induced secretion of IL-2. Although ISO increased the intracellular concentration of cAMP in untreated and Con A-treated T cells from all donors, cells from the normal and the non-asthmatic subjects, but not from the asthmatics, that were co-incubated with ISO and Candida had lower levels of cAMP than those treated with ISO alone. It is suggested that Candida antigen induces secretion of IL-2 and reduces ISO-inducible accumulation of cAMP in Candida-responsive IL-2 secreting cells, which may make Candida-induced secretion of IL-2 insensitive to ISO.

Asthma↗
PubMed1999

Paroxysmal kinesigenic choreoathetosis locus maps to chromosome 16p11.2-q12.1.

Paroxysmal kinesigenic choreoathetosis (PKC), the most frequently described type of paroxysmal dyskinesia, is characterized by recurrent, brief attacks of involuntary movements induced by sudden voluntary movements. Some patients with PKC have a history of infantile afebrile convulsions with a favorable outcome. To localize the PKC locus, we performed genomewide linkage analysis on eight Japanese families with autosomal dominant PKC. Two-point linkage analysis provided a maximum LOD score of 10.27 (recombination fraction [theta] =.00; penetrance [p] =.7) at marker D16S3081, and a maximum multipoint LOD score for a subset of markers was calculated to be 11.51 (p = 0.8) at D16S3080. Haplotype analysis defined the disease locus within a region of approximately 12.4 cM between D16S3093 and D16S416. P1-derived artificial chromosome clones containing loci D16S3093 and D16S416 were mapped, by use of FISH, to 16p11.2 and 16q12.1, respectively. Thus, in the eight families studied, the chromosomal localization of the PKC critical region (PKCR) is 16p11.2-q12.1. The PKCR overlaps with a region responsible for "infantile convulsions and paroxysmal choreoathetosis" (MIM 602066), a recently recognized clinical entity with benign infantile convulsions and nonkinesigenic paroxysmal dyskinesias.

Adolescent↗
PubMed1999

Analysis of where and which types of proteinases participate in lysosomal proteinase processing using bafilomycin A1 and Helicobacter pylori Vac A toxin.

Lysosomal proteinases are translated as preproforms, transported through the Golgi apparatus as proforms, and localized in lysosomes as mature forms. In this study, we analyzed which subclass of proteinases participates in the processing of lysosomal proteinases using Bafilomycin A1, a vacuolar ATPase inhibitor. Bafilomycin A1 raises lysosomal pH resulting in the degradation of lysosomal proteinases such as cathepsins B, D, and L. Twenty-four hours after the withdrawal of Bafilomycin A1, NIH3T3 cells possess these proteinases in amounts and activities similar to those in cells cultured in DMEM and 5% BCS. In the presence of various proteinase inhibitors, procathepsin processing is disturbed by E-64-d, resulting in abnormal processing of cathepsins D and L, but not by APMSF, Pepstatin A, or CA-074. In the presence of Helicobacter pylori Vac A toxin, which prevents vesicular transport from late endosomes to lysosomes, the processing of procathepsins B and D occurs, while that of procathepsin L does not. Thus, procathepsins B and D are converted to their mature forms in late endosomes, while procathepsin L is processed to the mature form after its arrival in lysosomes by some cysteine proteinase other than cathepsin B.

3T3 Cells↗
PubMed1999

Effect of beta-agonists on production of cytokines by activated T cells obtained from asthmatic patients and normal subjects.

Intracellular levels of cAMP were found to regulate T cell activity. We examined whether beta2-agonists altered cytokine production and cyclic adenosine monophosphate (cAMP) accumulation in concanavalin A (ConA)-activated peripheral T cells from asthmatic patients. Procaterol and isoproterenol weakly decreased the ConA-elicited interleukin (IL)-4 and IL-5 secretion; however, the inhibitory effect of procaterol on the ConA-induced IL-2 secretion was inferior to that of isoproterenol in normal controls and was little in asthmatics. The intracellular accumulation of cAMP by procaterol was not altered compared with that by isoproterenol. Results suggest that there is a qualitative difference between procaterol- and isoproterenol-induced cAMP accumulation in T cells.

Adrenergic beta-Agonists↗
PubMed1999

[Lung cancer with chylothorax successfully treated by chemical pleurodesis with OK-432].

A 66-year-old man was admitted to our hospital because of bloody sputum. Chest computed tomographic scans disclosed a right hilar tumor. A tumor in the right upper-lobe bronchus was detected by fiberoptic bronchoscopy. Microscopic examination disclosed moderately differentiated squamous cell carcinoma. The patient was treated with irradiation and combination chemotherapy. Thereafter, right chylous pleural effusion developed and continued to accumulate. Pleurodesis was induced by the intrathoracic injection of OK-432 at 15 KE per dose. Lung cancer with nontraumatic chylothorax is rare. In our patient, pleurodesis with OK-432 was an effective treatment.

Aged↗
PubMed1999

[A study of aggravation of atopic dermatitis during Japanese cedar pollen season--correlation with grades of dermatitis on face and Cry j 1 specific IgE].

We studied influence of Japanese cedar pollen (Jcp) on aggravation of atopic dermatitis (AD) during the pollination season. 48.5% of 97 patients with atopic dermatitis showed aggravation of dermatitis during the pollination season and 85% of them had Japanese cedar pollinosis, whereas only 44% of AD patients without the aggravation had the pollinosis. There was no difference of grades of dermatitis on face between the groups with or without the aggravation. Furthermore, we measured specific IgE to Jcp and Cry j 1, a major allergen of Jcp, by ELISA in the sera from the 54 patients with AD. The levels of specific IgE antibodies to both allergens in the group with the pollinosis were significantly higher than in the group without the pollinosis. However, significant difference of those was not recognized between the groups with or without the aggravation of AD. Therefore, our study has suggested that Japanese cedar pollen is likely to be one of causes of seasonal aggravation of AD in individuals sensitized to the pollen, and some other factors, e.g. Jcp-specific T cells, might play an important roll in addition to the Jcp-specific IgE.

Adolescent↗
PubMed1999

[Developmental changes of awareness during passive and active attentions: evaluation of serial event-related potentials (N130, N180, P250)].

Serial event-related potentials (ERPs), especially the negative components before P300, were recorded to evaluate the developmental changes of awareness, or intentional attention. In this study, 36 healthy children (5-16 years of age) and eight healthy adults (19-37 years) were told to perform two attentive paradigms: passive and active. Each test condition consisted of 16 electrical stimuli. Four trials were averaged in sequence and then evaluated as serial four blocks. With repetition in both passive and active attentive paradigms the amplitude of N130 was not attenuated until six years old. During active attention, N180 remained undiminished in adolescents and adults. The amplitude of P250 decreased with repetition during passive attention in children over seven years old, but was not attenuated during active attention in adults. These results suggest that N130 reflects the orienting reflex, and that N180 is associated with the process to maintain awareness.

Adolescent↗
PubMed1999

[Quantitative measurement of prefrontal lobe volume on three dimensional magnetic resonance imaging scan].

This article describes the measurement of the frontal and prefrontal lobe volumes on three dimensional (3-D) MRI in 13 children aged 5 months to 14 years and in 3 adults aged 27 to 39 years. The 3-D MRI data were acquired by the fast spoiled gradient recalled (SPGR) sequence using a 1.5 T MR imager. The frontal and prefrontal lobe volumes were measured by the volume measurement function of the Workstation. We confirmed that this technique to analyze segmental brain volumes achieved acceptable levels of reliability and accuracy. There was an increase in the frontal and prefrontal lobe volumes with advancing age, being rapid between 8 and 15 years of age. The prefrontal to frontal lobe volume ratio also increased gradually, with spurts between 8 and 15 years of age. This approach may be particularly useful for studies on patients with frontal and prefrontal lobe dysfunctions.

Adolescent↗
PubMed1998

Eye socket reconstruction with free flaps in patients who have had postoperative radiotherapy.

It is difficult to fit an ocular prosthesis and correct periorbital depression deformity in a patient who has undergone radiotherapy after enucleation of the eye for retinoblastoma during infancy. Simultaneously, developmental disturbances of the eyelids and severe periorbital depression deformities develop. However, due to recent advances in microvascular surgery, free flap transplantation is increasingly used for eye socket reconstruction because of its good circulatory effects with enough volume to augment large periorbital tissue defects. In the present study, we report on our success in using a free groin flap, scapular flaps and parascapular flaps simultaneously for reconstruction of eye sockets and correction of depressed deformities.

Adult↗
PubMed1998

Effects of recombinant human bone morphogenetic protein-2 on differentiation of cells isolated from human bone, muscle, and skin.

We investigated the effects of recombinant human BMP-2 (rhBMP-2) on differentiation of cells isolated from human bone, muscle, and skin. Cells isolated from bones of six patients (HBM-1 to HBM-6), muscle from five patients (HM-1 to HM-5), and skin from three patients (HF-1 to HF-3) were used. rhBMP-2 had no effects on proliferation of two HBM cells, but had a stimulatory effect on three HM cell samples. rhBMP-2 stimulated both alkaline phosphatase (ALP) activity in all HBM cells and parathyroid hormone (PTH)-dependent cAMP production in three of the four HBM cell samples, although the magnitudes of these stimulatory effects differed among the cells tested. Although none of the HBM cells examined produced detectable amounts of osteocalcin in the absence of 1,25-(OH)2vitamin D3, they synthesized measurable amounts of osteocalcin in its presence. rhBMP-2 inhibited 1,25-(OH)2vitamin D3-dependent osteocalcin production in all of the HBM cell samples. Transplantation of HBM-6 cells with rhBMP-2 using diffusion chambers into the peritoneal cavity of athymic mice induced formation of cartilage and bone in the diffusion chambers, but neither cartilage nor bone was formed in chambers transplanted without rhBMP-2. rhBMP-2 also stimulated ALP activity in all of the HM and HF cell samples examined and PTH-dependent cAMP production in three of four HM cell samples. rhBMP-2 induced no osteocalcin production in any of the HM or HF cells in the presence of 1,25-(OH)2vitamin D3. rhBMP-2 markedly inhibited myotube formation by all of the HM cell samples. Transplantation of HM-4 cells with rhBMP-2, using diffusion chambers, into athymic mice induced ALP-positive cells in the chambers, but neither cartilage nor bone was observed. These results suggest that rhBMP-2 is a potent stimulator of osteoblast differentiation and bone formation in human cells.

Alkaline Phosphatase↗
PubMed1998

Changes in endothelin-1, 6-keto-PG-F1 alpha, and TX-B2 in random pattern flaps.

In this study we investigated kinetic changes in the ratio of endothelin-1 (ET-1) and eicosanoids (6-keto-PG-F1 alpha TX-B2) in 20 x 60 mm random pattern flaps from rats. The ET-1 content of regions A (20 mm from the peripheral end) and B (20-40 mm) 6 h after surgery tended to decrease slightly compared to the ET-1 content immediately after surgery. The ET-1 content of region C (20 mm from the flap base) 6 h postoperatively increased significantly compared to that immediately after surgery. The ET-1 content of region C 6 h after surgery was significantly higher compared to that of regions A and B, which were obtained simultaneously. The ratios of eicosanoids in the three regions 6 h after surgery were significantly lower than those immediately after operation. However, the ratio in region A was higher than that in region C, showing that there was a difference in distribution in the flap between ET-1 and eicosanoids. The administration of an ETA receptor antagonist, FR-139317, extended the survival length of the flap. These results suggest that ET-1 can regulate the microcirculation in a flap directly and/or indirectly.

6-Ketoprostaglandin F1 alpha↗
PubMed1998

Effect of rebamipide, a novel antiulcer agent, on Helicobacter pylori adhesion to gastric epithelial cells.

Helicobacter pylori is a major etiological agent in gastroduodenal disorders. The adhesion of H. pylori to human gastric epithelial cells is the initial step of H. pylori infection. Inhibition of H. pylori adhesion is thus a therapeutic target in the prevention of H. pylori infection. Experiments were performed to evaluate the effect of rebamipide, a novel antiulcer agent, on H. pylori adhesion to gastric epithelial cells. MKN-28 and MKN-45 cells, derived from human gastric carcinomas, were used as target cells. Ten H. pylori strains isolated from patients with chronic gastritis and gastric ulcer were used in the study. We evaluated the effect of rebamipide on H. pylori adhesion to MKN-28 and MKN-45 cells quantitatively using our previously established enzyme-linked immunosorbent assay. The adhesion of H. pylori to MKN-28 and MKN-45 cells was significantly inhibited by pretreatment of these cells with 100 microg of rebamipide per ml. However, the adhesion was not affected by the pretreatment of H. pylori with rebamipide. On the other hand, the viabilities of H. pylori, MKN-28 cells, and MKN-45 cells were not affected by rebamipide. Our studies suggest that rebamipide inhibits the adhesion of H. pylori to gastric epithelial cells.

Alanine↗
PubMed1998

[Electrophysiologic evaluation of passive and active attentions--I. Topographic analysis of somatosensory event-related potentials].

We studied the topography of somatosensory event-related potentials (SERP) in two different attentive conditions: passive and active. Seventeen healthy right-handed young men, aged 19 to 28 years old (average age; 22.9 years), were requested to perform the following four paradigms in turn. In the passive attentive paradigm, participants were given no specific task when 0.3 Hz electrical stimuli were at random delivered to the right median nerve. In the active attentive paradigm, subjects were required to direct their attention to the regular 0.3 Hz stimuli with all their might. In the control paradigm. 2.0 Hz stimuli were delivered as they listened to their favorite music. Finally, in the oddball paradigm, subjects were instructed to push a button whenever they detected rare stimuli. SERP was recorded at 13 electrodes Grand average topographic amplitude maps from the individual data of the seventeen subjects were made at the latencies of N 60, P 90, N 130 and P 250 for each of the four paradigms. The topographic maps of P 250, the largest positive peak between 200 and 300 msec after the stimuli, showed a significant difference in the distribution of amplitude in the passive and active attentive paradigms compared to the control paradigm. A statistically significant enhancement was noted at the central region in the passive attention, and at the central and frontal regions in the active attention. These results suggest that P 250 consists of two attentive components distinct from selective or discriminative attention. The enhanced positivity at the frontal region during active attention may be associated with expecting the next stimulus and maintaining awareness.

Adult↗
PubMed1998

[Electrophysiologic evaluation of passive and active attentions--II. Developmental changes of somatosensory event-related potentials in different attentive paradigms].

By somatosensory event-related potentials (SERP) we have previously demonstrated in adults that an enhanced positivity of P 250 is statistically significant at the frontal region during the active attentive state. We have also evaluated developmental changes of P 250 during different attentive states: passive and active. In this study, 30 healthy children (5-16 years of age) and six healthy adults (23-41 years) were required to perform the following four paradigms: passive attentive, active attentive, control, and oddball. SERP were recorded at Fz, Cz and Pz. In the passive attentive paradigm, P250 amplitude at Fz, Cz and Pz remained constant irrespective of age. With regard to the topography of the amplitude, however, P 250 was distributed dominantly at Pz in Group 1 (5-6 years of age) and Group 2 (7-11 years), contrary to the dominance at Cz in both Group 3 (12-16 years) and adults. In the active attentive paradigm, on the other hand, the P 250 amplitude at Fz reached its minimum at about 10 years and then increased until the adulthood. With respect to the topography of the amplitude, P 250 was distributed dominantly at Pz in Groups 1 and 2, at Cz in Group 3, and at Fz and Cz in adults. These results suggest that the topographic changes in the active attentive paradigm are dependent upon the developing abilities to expect the next stimulus and to maintain awareness.

Adolescent↗