Fibrillar architecture at three different sites of the bovine superficial digital flexor tendon.

Superficial digital flexor tendon (SDFT) of the bovine hindlimb originates from the caudolateral aspect of the distal femur and finally inserts onto the plantar aspect of the middle phalanges. In the present study, morphology and morphometry of the bovine SDFT at the muscle-tendon junction (MTJ), middle metatarsus (mM) and tendon-bone interface (TBI) were investigated. Cross-sectional morphology at the three regions of SDFT were oval, semioval and ring-formed, respectively. Significant difference in cross-sectional area was found only between MTJ-mM and mM-TBI (P<0.05). Functional compression and friction from the adjacent structures could be the most potential interactions affecting such appearances. Morphometric data of tenocyte number, water content, and glycosaminoglycan (GAG) length and angle were found increasing in the proximodistal direction, except the fibril diameter and collagen fibril index (CFI). Statistical analyzes could reveal significant differences in average number of tenocytes (P<0.0001), CFI (between MTJ-mM and MTJ-TBI, P<0.05), water content (between MTJ-TBI, P<0.05), length of GAG chains (between MTJ-TBI, P<0.05), and angle of GAG chains (P<0.0001), respectively. The fibrillar characteristics at the three different areas, including fibril diameter distribution and interfibrillar distance, existed in conforming to the tensional axes in situ. In addition, length and angle of GAG chains were relevant to moving directions of the collagen fibrils.

Remodeling of rat stromal-vascular cells to brite/beige adipocytes by prolyl-hydroxyproline.

The aim of this study was to determine the effects of prolyl-hydroxyproline (Pro-Hyp) on the proliferation and differentiation of rat stromal-vascular cells (SVCs) being cultured in a medium with (Pro-Hyp group) or without Pro-Hyp (control group). The results showed that there was no significant difference in proliferation rate of SVCs, lipid droplet (LD) diameter or intracellular concentration of triglycerides between two groups. However, the diameter range of LDs in the Pro-Hyp group tended to be smaller than that in the control group. Transmission electron microscopy showed a tendency for increase in the area of mitochondria and decrease in the number of mitochondria in the Pro-Hyp-treated SVCs. The mRNA expression levels of white adipose tissue differentiation markers (Cbp, Fabp and Serpina3k) were significantly lower, but those of the brown adipose tissue differentiation markers (Dio2, Ucp1 and Ucp3) were significantly higher in the Pro-Hyp group than in the control group. Our results suggested that Pro-Hyp can facilitate SVCs to differentiate into "brite/beige" adipocytes.

Crucial factor causing collapse and aggregation of cultured cells in epon resin.

Ultrastructural artifacts regarding collapse and aggregation of cultured cells have been problematic, especially when investigated apoptotic cells. The infiltration process during sample preparation is considered to be the most crucial factor for this problem. This study was conducted using two culture systems: a suspension culture system of human T-lymphocyte Jurkat cells and rabbit mature dendritic cells and a monolayer culture system of human lung macrophages, human breast cancer cells (A-546 cells) and cat bone-invasive gingival cancer cells (sccf3 cells). Fixation was conducted prior to removing or detaching the cells from the culture dishes. Initial infiltration with a 1 : 3 volume ratio of epon resin : propylene oxide was found to be the most crucial step among these cultured cells. The improved epon-resin infiltration method could eliminate the artifacts. Thus, differentiation between artifactual images and true images is highly possible.

Histological differences of skin among three body regions in male and female Hokkaido sika deer (Cervus nippon yesoensis).

The Hokkaido sika deer (Cervus Nippon yesoensis), the largest and most abundant of the sika deer subspecies in Japan, has recently attracted new attention as a target for leather production, in addition to its meat value. To provide fundamental data for facilitating the effective use of skin for leather, the histological properties of skin at the shoulder, back and abdominal regions of male and female deer were compared. The results showed that the thickness of the outer skin layer was not significantly different across all regions irrespective of sex. Regarding collagen composition, we found that large-diameter collagen fibrils were heavily distributed in the shoulder of male deer, whereas small-diameter collagen fibrils were largely confined to the abdomen of female deer. We hope this regional histological data will lead to more efficient processing of Hokkaido sika deer skin for leather production.

Efficacy of self-assembled hydrogels composed of positively or negatively charged peptides as scaffolds for cell culture.

KASEA16(+) and KASEA16(-) peptides, the net charges of which are positive and negative, respectively, under a neutral condition could undergo self-assembly into nanofibers and form transparent hydrogels without peptide aggregation upon rapid pH neutralization. The numbers of NIH3T3 cells attached to the KASEA16(+) hydrogel and KASEA16(-) hydrogel were similar, and cells proliferated with time on both hydrogels. Cells on the KASEA16(+) hydrogel had spindle-like morphology, while cells on the KASEA16(-) hydrogel formed clusters without extending cytoplasmic processes. Comparison of differently charged peptides under a neutral condition suggested that the charges of the scaffolds should be taken into consideration for the best design and selection of scaffolds for cell culture. Since the KASEA16(+) peptide could form a stable hydrogel under a neutral condition and the hydrogel served as a scaffold for cell proliferation, the KASEA16(+) hydrogel will be a useful scaffold for cell culture.