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Biomedical subjects

Takashi Abe

Publications and source records attributed to Takashi Abe.

64 records · Page 4Linked to original sources
PubMed2002

Remarkable increase in the concentration of 8-hydroxyguanosine in cerebrospinal fluid from patients with Alzheimer's disease.

To investigate the possible role of oxidative RNA damage in the pathogenesis of Alzheimer's disease (AD), the concentrations of the oxidative stress marker 8-hydroxyguanosine (8-OHG) were measured in the cerebrospinal fluid (CSF) and the serum of patients with AD and control subjects. The concentration of 8-OHG in CSF in AD patients was approximately fivefold that in controls (P < 0.001). The concentration of 8-OHG in CSF decreased significantly with the duration of illness (r(s) = -0.48, P < 0.05) and the progression of cognitive dysfunctions (r(s) = 0.67, P < 0.01). However, the concentration of 8-OHG in CSF showed no correlation with that in serum in both the controls and AD patients. In addition, the concentration of 8-OHG in serum was not significantly altered in AD patients compared to that in controls, suggesting that the 8-OHG concentrations in the CSF do not reflect those in serum and may be probably reflect those in brain tissue. These in vivo findings suggest a possible role of 8-OHG and increased oxidative RNA damage in the early stage of the development of AD.

Aged↗
PubMed2002

Generation of functional and mature dendritic cells from cord blood and bone marrow CD34+ cells by two-step culture combined with calcium ionophore treatment.

The object of this study is to explore a culture method to generate a large number of functional and mature dendritic cells (DC) from human CD34+ hematopoietic progenitor cells. In the present study, we used a two-step method combined with calcium ionophore to induce DC from cord blood (CB) or normal human bone marrow (BM) CD34+ progenitor cells. The two-step method consists of 10 days of first step culture for the expansion and proliferation of CD34+ hematopoietic progenitor cells in the presence of SCF, IL-3, IL-6, G-CSF, and 7--11 days of second step culture for the induction of DC in the presence of GM-CSF, IL-4 and TNF-alpha. By the two-step culture, total nucleated cells were increased 208+/-66 (+/-SD, n=13), or 94+/-29 (n=5)-fold in the culture of CB or BM cells, respectively, compared with the number of CD34+ cells at the time of starting culture. Out of the total nucleated cells, 23 +/-10.4% of cells in CB cell culture and 25 +/-5% of cells in the BM cell culture acquired DC characteristic phenotypes, which were marked expressions of CD1a, HLA-DR, co-stimulatory molecules such as CD80, CD40, and adhesion molecule such as CD58. In allogeneic mixed leukocyte reaction (MLR), two-step cultured cells showed potent allo-stimulatory capacity. With this two-step culture, the absolute number of CD1a+ cells that co-expressed HLA-DR, CD80, CD40 and CD58 was enhanced approximately 3 times in CB cell culture and 1.9 times in BM cell culture, compared with the commonly used one-step culture method for the generation of DC from CD34+ cells using SCF, GM-CSF and TNF-alpha. However, on these DC generated in the two-step culture, the expressions of co-stimulatory molecule CD86 and mature DC marker CD83 were not sufficient. By the treatment of two-step cultured cells with calcium ionophore agent (A23187), the expression of co-stimulatory molecules such as CD86 and CD80 (especially CD86) was up-regulated. Besides, the expression of mature DC marker CD83 was remarkably induced by treatment with A23187 for a short duration (24 h). Consistent with the up-regulation of surface molecules CD86, CD80 and CD83, the two-step cultured cells treated with A23187 also showed a stronger allo-stimulatory capacity compared with the cells without A23187 treatment. In conclusion, the present study demonstrated that the two-step culture method effectively improved the yield of CD1a+ DC generated from CD34+ cells, and the phenotypes and functions of these CD1a+ DC could be enhanced efficiently by treatment with a calcium ionophore agent.

Antigens, CD34↗
PubMed2002

The role of FFM accumulation and skeletal muscle architecture in powerlifting performance.

The purpose of this study was to determine the distribution and architectural characteristics of skeletal muscle in elite powerlifters, and to investigate their relationship to fat-free mat (FFM) accumulation and powerlifting performance. Twenty elite male powerlifters (including four world and three US national champions) volunteered for this study. FFM, skeletal muscle distribution (muscle thickness at 13 anatomical sites), and isolated muscle thickness and fascicle pennation angle (PAN) of the triceps long-head (TL), vastus lateralis, and gastrocnemius medialis (MG) muscles were measured with B-mode ultrasound. Fascicle length (FAL) was calculated. Best lifting performance in the bench press (BP), squat lift (SQT), and dead lift (DL) was recorded from competition performance. Significant correlations (P < or = 0.01) were observed between muscle distribution (individual muscle thickness from 13 sites) and performance of the SQT (r = 0.79 to r = 0.91), BP (r = 0.63 to r = 0.85) and DL (r = 0.70 to r = 0.90). Subscapular muscle thickness was the single best predictor of powerlifting performance in each lift. Performance of the SQT, BP, and DL was strongly correlated with FFM and FFM relative to standing height (r = 0.86 to 0.95, P < or = 0.001). FAL of the triceps long head and vastus lateralis were significantly correlated with FFM (r = 0.59, P < or = 0.01; 0.63, P < or = 0.01, respectively) and performance of the SQT (r = 0.45; r = 0.50, respectively; P < or = 0.05), BP (r = 0.52; r = 0.56, respectively; P < or = 0.05), and DL (r = 0.56; r = 0.54, respectively; P < or = 0.01). A significant positive correlation was observed between isolated muscle thickness and PAN for triceps long-head (r = 0.64, P < or = 0.01) and gastrocnemius medialis (r = 0.48, P < or = 0.05) muscles, but not for vastus lateralis (r = 0.35). PAN was negatively correlated with powerlifting performance. Our results indicate that powerlifting performance is a function of FFM and, therefore, may be limited by the ability to accumulate FFM. Additionally, muscle architecture appears to play an important role in powerlifting performance in that greater fascicle lengths are associated with greater FFM accumulation and powerlifting performance.

Body Height↗
PubMed2002

SNP genotyping in the beta(2)-adrenergic receptor by electronic microchip assay, DHPLC, and direct sequencing.

The beta(2)-adrenergic receptor (beta2AR) is the key target for the beta(2)-agonist drugs used for bronchodilation in asthma and chronic obstructive pulmonary disease. To detect four SNPs with amino acid variations at positions -47T/C (CysBUP19Arg), 46A/G (Gly16Arg), 79C/G (Gln27Glu), and 491C/T (Thr164Ile) in the beta 2AR gene, we used the electronic microchip assay, denaturing high-performance liquid chromatography (DHPLC), and direct sequencing. Genomic DNA samples were obtained from the blood of 84 Japanese healthy volunteers. The agreement rates of the first data set with the final data (allele calls) were 99.7% (332/333), 99.2% (246/248), and 96.7% (329/340). The percentages of no allele designation (ND) were 2.06% (7/340), 2.75% (7/255), and 0.00% (0/340) for the electronic microchip assay, DHPLC, and direct sequencing, respectively. Furthermore, we found three samples that had a novel haplotype.

Chromatography, High Pressure Liquid↗
PubMed2002

CD56+, NKp46+ cell line (MZ93) expressing T-cell and myeloid antigens.

The MZ93 cell line, established from a patient with CML, expressed CD4, CD7, CD13, CD25, CD33, CD34, CD56 and NKp46. The additional karyotype abnormality of the Ph-positive leukemia cells in vivo, 6p+, was also observed in MZ93. The early passages of MZ93 expressed CD3 in the cytoplasm, but the late passages did not. The cells did not express mature NK-markers as expected. The messenger RNAs of CD2 and NKp46 were detected and those of CD3varepsilon and CD3zeta were absent in the cells. Therefore, the cell line has the immunophenotype likely to NK and/or T cell precursor.

Antigens, CD↗
PubMed2002

Relation between fat distributions and several plasma adipocytokines after exercise training in premenopausal and postmenopausal women.

Circulating concentrations of adipocytokines, such as leptin, tumor necrosis factor-alpha (TNF-alpha), and plasminogen activator inhibitor-1 (PAI-1), vary with exercise training, menopause, or regional variations in adipose tissues. In the present study, the relationships between body fat distributions and some adipocytokines were compared in premenopausal (N = 9) and postmenopausal women (N = 9), before and after exercise training. The training for 10 weeks (that is, 3 days/week) consisted of aqua exercise plus resistance exercise. The training reduced percent fat, body mass index, total fat mass (TFM), subcutaneous fat mass (SFM), and plasma levels of leptin and PAI-1 in both women. Mean value of plasma TNF-alpha tended to increase after training in both women. Plasma leptin levels were lower in postmenopausal than in premenopausal women, independently of training. In premenopausal women, plasma leptin levels correlated well with either TFM or SFM before and after training. Regression analysis of decreases in plasma leptin with a reduced amount of SFM revealed that decreases in plasma leptin depended to a greater extent on a loss of SFM. In postmenopausal women, no significant correlation was found between leptin levels and any of the fat depots. Plasma TNF-alpha levels correlated well with visceral fat mass (VFM) in premenopausal but not in postmenopausal women. Changes in TNF-alpha levels after training correlated well with reduced amount of VFM in premenopausal but not in postmenopausal women. Plasma PAI-1 levels were not different between groups. Moreover, no significant correlation was found between PAI-1 levels and any of the fat depots in both women. Thus, in premenopausal but not in postmenopausal women, changes in plasma concentrations of leptin and TNF-alpha correlate well with specific alterations in relative amount of SFM and VFM after training, respectively. However, no significant relationship between PAI-1 and any of the fat depots was found independently of either menopause or training.

Adipose Tissue↗
PubMed2002

Fascicle length of gastrocnemius muscles in monozygous twins.

A large inter-individual variation is seen in muscle fascicle length of the athletes but the reasons for this phenomenon are unclear. The purpose of this study was to determine whether genetic factors contribute to the variances in muscle architectural characteristics. Nine monozygous twin pairs (3 males and 6 females), mean age 23 years (range 17-40) were studied. Fascicle length, pennation angle, and muscle thickness of the medial (MG) and lateral (LG) gastrocnemius muscles were measured in vivo by B-mode ultrasound. In the LG muscle intrapair resemblance (P < 0.01) for fascicle length (r = 0.98), pennation angle (r = 0.94) and muscle thickness (r = 0.86) were observed. In MG muscle, however, there was no intrapair resemblance for fascicle length (r = 0.66, P > 0.05), although pennation angle (r = 0.73, P < 0.05) and muscle thickness (r = 0.86, P < 0.01) were significant. Mean percent intrapair difference in LG and MG muscles were 1.8% and 5.1% for fascicle length, 11.3% and 12.3% for pennation angle and 12.4% and 9.9% for muscle thickness, respectively. There is intrapair difference between muscle thickness and pennation angle in both MG (r = 0.69, P < 0.05) and LG (r = 0.70, P < 0.05) muscles. However, no significant correlation was observed for intrapair difference between muscle thickness and fascicle length in both muscles (MG, r = 0.46; LG, r = 0.40). It appears that genetic predisposition is the predominant factor for the determination of muscle fascicle length. However, a lack of intrapair resemblance in MG fascicle length raises the possibility that fascicle length may be further influenced by external environmental factors such as physical training.

Adolescent↗
PubMed2002

A novel bioinformatic strategy for unveiling hidden genome signatures of eukaryotes: self-organizing map of oligonucleotide frequency.

With the increasing amount of available genome sequences, novel tools are needed for comprehensive analysis of species-specific sequence characteristics for a wide variety of genomes. We used an unsupervised neural network algorithm, Kohonen's self-organizing map (SOM), to analyze di- and trinucleotide frequencies in 9 eukaryotic genomes of known sequences (a total of 1.2 Gb); S. cerevisiae, S. pombe, C. elegans, A. thaliana, D. melanogaster, Fugu, and rice, as well as P. falciparum chromosomes 2 and 3, and human chromosomes 14, 20, 21, and 22, that have been almost completely sequenced. Each genomic sequence with different window sizes was encoded as a 16- and 64-dimensional vector giving relative frequencies of di- and trinucleotides, respectively. From analysis of a total of 120,000 nonoverlapping 10-kb sequences and overlapping 100-kb sequences with a moving step size of 10 kb, derived from a total of the 1.2 Gb genomic sequences, clear species-specific separations of most sequences were obtained with the SOMs. The unsupervised algorithm could recognize, in most of the 120,000 10-kb sequences, the species-specific characteristics (key combinations of oligonucleotide frequencies) that are signature representations of each genome. Because the classification power is very high, the SOMs can provide fundamental bioinformatic strategies for extracting a wide range of genomic information that could not otherwise be obtained.

Animals↗