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C Fujiyama

Publications and source records attributed to C Fujiyama.

28 records · Page 2Linked to original sources

Distribution of HLA and haplotypes of Colombian and Jamaican black populations.

To investigate the genetic background of the black populations of Colombia and Jamaica, we determined HLA types of 78 Colombian and 98 Jamaican blacks from 2 different socioeconomic groups (Jamaican #1 and Jamaican #2) and estimated the frequencies of HLA genes and haplotypes. A phylogenetic tree based on the HLA gene frequencies revealed that Jamaican #1 and Jamaican #2 were distinct from each other, Jamaican #1 being closely related to the Colombian blacks and the Jamaican #2 being closely related to Senegalese and Zairean populations. Three-locus HLA haplotypes of Colombian and Jamaican #1 blacks were an admixture between Africans and Caucasians or South American Indians, while Jamaican #2 blacks were relatively homogeneous and appeared to conserve African lineages. The major five-locus HLA haplotypes were not shared among Colombian, Jamaican #1 and Jamaican #2 blacks. These results indicated that the black populations of Colombia and Jamaican were originated from African blacks and admixed variably with Caucasians and South American Indians to make genetic subpopulations in Colombia and Jamaica.

Black People↗

[Megaureter in adults].

In comparison with megaureters in children, their reports in adult are not common. We had an opportunity to treat seven adults with megaureters during the last six years. They were all female and ages ranged from 46 to 67 years. Five patients with grade II and one with grade III (Pfister-Hendren's classification) were treated by reconstructive surgery, excision of the narrow segment, tapering of the dilated lower ureter and reimplantation through a submucosal tunnel. The outcome of all the grade II patients was excellent and the case with grade III showed mild improvement. The results suggested that surgical reconstruction could be equally effective for megaureters in adults compared to those in children.

Aged↗

Evaluation of commercial HTLV-1 test kits by a standard HTLV-1 serum panel.

To evaluate the performance of currently available test kits for human T-cell lymphotropic virus type 1 (HTLV-1), we examined two particle agglutination (PA) tests and nine enzyme immunoassays (EIA) using a standard serum panel consisting of HTLV-1-positive and HTLV-1-negative sera that had been characterized by immunofluorescence and the polymerase chain reaction (PCR). The PA kits exhibited 94.0-100.0% sensitivity and 99.5-100.0% specificity; the sensitivity range was ascribed to the quality of the HTLV-1 antigens coated on the particles. The EIA kits had 99.5-100% sensitivity and 98.5-100% specificity; the 98.5%-99.5% specificity exhibited by five of the EIA kits could have been due to nonspecific reactions that were detected through use of an inadequate cut-off value and the use of recombinant proteins. It can be concluded that the sensitivity of the currently available PA and EIA kits is sufficient to permit their use for screening purposes; however, the specificity of some EIA kits should be optimized.

Agglutination Tests↗

Reconstruction of the urinary bladder mucosa in three-dimensional collagen gel culture: fibroblast-extracellular matrix interactions on the differentiation of transitional epithelial cells.

The purpose of this study was to reconstruct a urinary bladder mucosa in three-dimensional collagen gel culture conditions that included fibroblasts. Transitional epithelial cells and fibroblasts, isolated respectively from the epithelial and lamina propria layers of porcine urinary bladder, were cultured in monolayer. These fibroblasts were embedded and cultured within a collagen gel matrix to reconstruct a lamina propria. The isolated transitional epithelial cells were then seeded in vitro on this reconstructed lamina propria on which the transitional epithelial cells formed a stratified urothelium composed of basal, intermediate and superficial layers. Urothelial differentiation was observed only on the fibroblast-containing collagen matrix. Differentiation did not occur on a cell-free collagen matrix through use of fibroblast conditioned medium. Thus, urothelial differentiation depended upon a fibroblast-extracellular matrix interaction. The differentiated transitional epithelial cell layer thus produced closely resembled a urothelium in vivo. This culture model may provide a useful system in which to study various diseases of the urinary bladder.

Animals↗

Geographic independence of HTLV-I and HTLV-II foci in the Andes highland, the Atlantic coast, and the Orinoco of Colombia.

To clarify the ethnic specificity of human T cell leukemia virus type I (HTLV-I) and type II (HTLV-II) carriers among Colombian native Indians, we investigated the geographic distribution of HTLV-I and HTLV-II seroprevalence among the isolated ethnic groups of Mongoloid origin in the Andes highlands and the Atlantic coast of Colombia. HTLV-I carriers were found in 1.6% (1/62 samples) of Inga, 8.5% (5/59) of Kamsa, and 0% (0/55) of Cumbal Indians who live in the Andes highlands at 3000 m above sea level. On the other hand, HTLV-II carriers were found in 4.1% (5/123) of Wayuu Indians, who live in the Guajira region of the Atlantic coast of Colombia at a distance of 1000 km from the Andes highlands. This ethnic specificity of HTLV-II was similarly observed among Guahibo Indians in the Orinoco. The seroprevalence of HTLV-I and HTLV-II was mutually exclusive among Inga, Kamsa, and Wayuu Indians. These results suggest that HTLV-I and HTLV-II may have evolved among Mongoloid populations and been independently transmitted among two different lineages of Colombian native Indians, Andes highlanders and Atlantic coast lowlanders.

Adolescent↗

Influence of extracellular matrix on the proliferation and differentiation of adrenocortical cells in culture.

Extracellular matrix is indispensable for cell differentiation in vivo. The aim of this study is to examine effects of extracellular matrix on adrenocortical cells embedded in collagen gel in terms of cellular proliferation and differentiation. Dissociated human or bovine adrenocortical cells were embedded in collagen gel; the gel was then immediately thin-coated on the bottom of culture dishes. The cortical cells were thus trapped in collagen and cultured in monolayer, a suitable means for observation of culture cells. To the authors' best knowledge, this "collagen gel-embedded" monolayer culture is described here for the first time. Cortical cells were spherical in shape and had the activities of proliferation and steroid production in collagen gel matrix of this culture method. Aldosterone production in particular tended to be maintained much longer than in conventional monolayer culture. This method seems to provide a physiological environment in which to study the differentiation of cortical cells.

Adrenal Cortex↗

Reconstruction of alveolus-like structure from alveolar type II epithelial cells in three-dimensional collagen gel matrix culture.

The purpose of this study is to reconstruct an alveolus-like structure from alveolar type II epithelial cells in a culture condition. Isolated alveolar type II epithelial cells of the rat were cultured in a three-dimensional collagen gel matrix. Single type II cells formed cellular aggregates that had a lumen after cell division in this culture condition. Through proliferation of the component cells, these aggregates grew to assume a globular or branching structure, part of which in turn developed into a large, cystic alveolus-like structure. This structure consisted of flattened epithelial cells intermingled with cuboidal epithelial cells. In these structures, the surfactant production was confirmed by immunohistochemistry and electron microscopy. To our knowledge, this is the first report of a reconstruction of an alveolus-like structure in a three-dimensional collagen gel matrix culture. This culture system seems to provide an appropriate physiological environment in which to study the differentiation and disorders of pulmonary alveoli.

Animals↗

Voiding dysfunction in patients with human T-lymphotropic-virus-type-1-associated myelopathy.

Voiding dysfunction in patients with human T-lymphotropic-virus-type-1-associated myelopathy (HAM) was studied. All the patients were diagnosed as having HAM by neurologists. We have already reported on 16 consequent patients with HAM. Almost all of these patients had frequency, and many had urge incontinence of urine and difficulty on voiding. Urodynamic study revealed that their voiding symptoms seemed to be due to detrusor hyperactivity and detrusor-sphincter dyssynergia. However, we have recently treated 2 patients who had a different bladder function. They had both frequency and difficulty in voiding but without urgency. In the urodynamic study both patients did not have involuntary bladder contraction during the filling phase and could not void voluntarily. The reason why these 2 patients had an underactive detrusor is unclear. The fact that the average duration of HAM in the 16 patients previously mentioned was longer than that of the latter 2 patients may suggest that overactivity of the bladder is not prominent in the early phase of this disease.

Female↗