Foot Problems and Their Associations with Toe Grip Strength and Walking Speed in Community-Dwelling Older Individuals Using Day Services: A Cross-Sectional Study.

Foot disorders in older individuals compromise balance and contribute to postural and gait instabilities, causing a decrease in the activities of daily living and quality of life. In this cross-sectional study, we analyzed the foot-related data of 160 frail older participants who attended day service centers in A prefecture in Japan to determine the prevalence of foot problems and their associations with toe grip strength and walking speed in frail older people. Multiple regression analysis was used to identify foot-related variables that correlated with toe grip strength and walking speed. The prevalence rates of skin dryness (Support level 88.2%, Care level 85.2% for men; Support level 84.9%, Care level 93% for women) and suspected and existing fungal infections in nails (Support level 94.1%, Care level 92.6% for men; Support level 98.1%, Care level 95.2% for women) were high in both sexes regardless of the level of care required. Furthermore, in both sexes, the prevalence rates of toe and arch deformities were significantly increased in the people who required care. Regression analysis revealed that some right-sided foot-related problems were significantly associated with right toe grip strength and walking speed. The decrease in toe grip strength was significantly associated with walking speed. Our study provides evidence that some specific conditions were associated with toe grip force and walking speed. This finding can contribute to future strategies to protect foot health in community-dwelling older individuals.

Plaque modification using a cutting balloon is more effective for stenting of heavily calcified lesion than other scoring balloons.

Cutting balloons (CBs) and other scoring balloons are known to be useful for plaque modification in heavily calcified lesions. There have been some reports of the efficacy of these balloons compared to conventional balloons. However, there have been no reports exploring which balloon is most effective among these three types of balloons. We, therefore, compared these three balloons with respect to effectiveness in plaque modification of calcified lesions. We retrospectively investigated 201 cases using these three balloons from April 2015 to December 2017. Of these cases, 156 with severe calcified lesions that had undergone intravascular ultrasound (IVUS) or optical frequency domain imaging (OFDI) were enrolled. The ratio of severe calcified lesion was higher in the CB group than in the groups of other balloons (p = 0.001), and IVUS and OFDI showed that a CB was more effective in plaque modification than the other balloons. The acute gain (minimum stent diameter minus minimum lumen diameter) and acute cross-sectional area (CSA) gain (minimum stent area minus minimum lumen area) were both larger in the CB group than in the others, and the stent symmetry index (minimum stent diameter/maximum stent diameter) showed that the CB group more closely approximated a perfect circle than the other groups (p = 0.0001, 0.006 and 0.002 for the acute gain, acute CSA gain and the stent symmetry index). Similar results were obtained in cases without rotational atherectomy. These data suggest that CB is more effective for plaque modification in cases of severe calcified lesions than other scoring balloons.

Comparison of the long-term effects on rabbit bone defects between Tetrabone and ß-tricalcium phosphate granules implantation.

Tetrabone is a newly developed granular artificial bone. The 1-mm Tetrabone has a four-legged structure. In this study, the long-term effect of implanting Tetrabone or ß-TCP granules in rabbit femoral cylindrical defects was evaluated. The rabbits were euthanized at 4, 13, and 26 weeks after implantation. Micro-CT was conducted to evaluate the residual material volume and the non-osseous tissue volume. New bone tissue areas were measured by histological analysis. Micro-CT imaging showed that the residual material volume in the ß-TCP group had decreased significantly at 4 weeks after implantation (P < 0.05) and that the ß-TCP granules had nearly disappeared at 26 weeks after implantation. In the Tetrabone group, it did not significantly change until 13 weeks after implantation; it then continued to decrease slightly until 26 weeks after implantation. The non-osseous volume increased in the ß-TCP group, whereas that of the Tetrabone group decreased (P < 0.05). Histological examination showed that the new bone areas were significantly greater in the Tetrabone group than in the ß-TCP group at 13 and 26 weeks. In conclusion, resorption of ß-TCP granules occurs before sufficient bone formation, thereby allowing non-osseous tissue invasion. Tetrabone resorption progressed slowly while the new bone tissues were formed, thus allowing better healing. Tetrabone showed better osteoconductivity, whereas the ß-TCP granules lost their function over a long duration. These results may be caused by the differences in the absorption rate of the granules, intergranular pore structure, and crystallinity of each granule.

Implantation of tetrapod-shaped granular artificial bones or ß-tricalcium phosphate granules in a canine large bone-defect model.

We investigated biodegradability and new bone formation after implantation of tetrapod-shaped granular artificial bone (Tetrabone®) or ß-tricalcium phosphate granules (ß-TCP) in experimental critical-size defects in dogs, which were created through medial and lateral femoral condyles. The defect was packed with Tetrabone® (Tetrabone group) or ß-TCP (ß-TCP group) or received no implant (control group). Computed tomography (CT) was performed at 0, 4 and 8 weeks after implantation. Micro-CT and histological analysis were conducted to measure the non-osseous tissue rate and the area and distribution of new bone tissue in the defect at 8 weeks after implantation. On CT, ß-TCP was gradually resorbed, while Tetrabone® showed minimal resorption at 8 weeks after implantation. On micro-CT, non-osseous tissue rate of the control group was significantly higher compared with the ß-TCP and Tetrabone groups (P<0.01), and that of the ß-TCP group was significantly higher compared with the Tetrabone group (P<0.05). On histology, area of new bone tissue of the ß-TCP group was significantly greater than those of the Tetrabone and control groups (P<0.05), and new bone distribution of the Tetrabone group was significantly greater than those of the ß-TCP and control groups (P<0.05). These results indicate differences in biodegradability and connectivity of intergranule pore structure between study samples. In conclusion, Tetrabone® may be superior for the repair of large bone defects in dogs.

Bone regeneration within a tailor-made tricalcium phosphate bone implant with both horizontal and vertical cylindrical holes transplanted into the skull of dogs.

A new tailor-made bone implant (TI) with six horizontal cylindrical holes fabricated from alpha-tricalcium phosphate powder, as described in our previous report, was modified to include five additional vertical holes (TI-v) in an attempt to accelerate the bone regeneration through the holes. This TI-v implant and hydroxyapatite implants (HI) as controls were transplanted into experimental skull defects in dogs. Computed tomography (CT) was performed immediately after the surgery and then every 4 weeks. The dogs were killed for histological analysis at 24 weeks of implantation. On CT, bone bridging between the implant and the skull was observed in the TI-v group from 8 weeks of implantation, whereas a clear bone bridge was not formed in the HI group after 24 weeks of implantation. Histological analysis revealed collagen tissues and new bone formation in the horizontal cylindrical holes in most of the TI-v group, whereas mainly connective tissues invaded the porous structures in the HI group. In the Ti-v group, at the middle of the horizontal holes where they crossed the vertical holes, fibrous collagen tissues and muscular tissue filled up the hole and new bone formation seemed to be blocked. However, in the TI-v group more collagen and bone tissues were formed than in the HI group; when compared with the data in our previous report, however, the total volume of regenerated bone in the horizontal cylindrical holes in the TI-v seemed to be less than that in the TI. Thus, the addition of vertical cylindrical holes in the TI-v was not effective in promoting the faster stabilization of the TI-v in the skull of the dog.

Tailor-made tricalcium phosphate bone implant directly fabricated by a three-dimensional ink-jet printer.

Rapid prototyping (RP) is a molding technique that builds a three-dimensional (3D) model from computer-aided design (CAD) data. We fabricated new tailor-made bone implants (TIs) from alpha-tricalcium phosphate powder using an RP ink-jet printer based on computed tomography (CT) data, and evaluated their safety and efficacy. CT data of the skulls of seven beagle dogs were obtained and converted to CAD data, and bone defects were virtually made in the skull bilaterally. TIs were designed to fit the defects and were fabricated using the 3D ink-jet printer with six horizontal cylindrical holes running through the implants, designed for possible facilitation of vascular invasion and bone regeneration. As a control, hydroxyapatite implants (HIs) were cut manually from porous hydroxyapatite blocks. Then, craniectomy was performed to create real skull defects, and TIs and HIs were implanted. After implantation, CT was performed regularly, and the animals were euthanized at 24 weeks. No major side effects were observed. CT analysis showed narrowing of the cylindrical holes; bony bridging between the implants and the temporal bone was observed only for TIs. Histological analysis revealed substantial new bone formation inside the cylindrical holes in the TIs, while mainly connective tissues invaded the porous structures in HIs. Bone marrow was observed only in TIs. Osteoclasts were seen to resorb regenerated bone from inside the cylindrical holes and to invade and probably resorb the TIs. These data suggest that TIs are a safe and effective bone substitute, possessing osteoconductivity comparable with that of HIs.

Determination of midazolam and its metabolite as a probe for cytochrome P450 3A4 phenotype by liquid chromatography-mass spectrometry.

This study demonstrated the analysis of midazolam and its metabolites by liquid chromatography-mass spectrometry (LC-MS) with a sonic spray ionization (SSI) interface. The analytical column was a YMC-Pak Pro C18 (50 mm x 2.0 mm i.d.) using 10 mM ammonium acetate (pH 4.8)-methanol (1:1) at a flow rate of 0.2 ml min(-1). The drift voltage was 100 V. The sampling aperture was heated at 110 degrees C and the shield temperature was 230 degrees C. The lower limits for the detection of midazolam and 1'-hydroxymidazolam were 26.3 and 112.76 pg injected, respectively. The calibration curves for midazolam and 1'-hydroxymidazolam were linear in the range of 0.1-5 microg ml(-1). Within-day relative standard deviations was less than 7%. The method was applied to the determination of midazolam in monkey plasma, and the analysis of midazolam and its metabolites in an in vitro study with recombinant cytochrome P450 (CYP) 3A4. This method is sufficiently sensitive and useful to elucidate the kinetics of midazolam metabolite formation. We also investigated the effect of propofol on the metabolism of midazolam using recombinant CYP3A4. Propofol competitively inhibited the metabolism of midazolam to 1'-hydroxymidazolam by CYP3A4.

The expression of sialyl Lewis X in canine and feline mammary gland tumors.

The expression of sialyl Lewis X (sLe(x)) in 93 canine and 15 feline mammary gland tumors (MGT) obtained by surgical resection at Veterinary Medical Center, the University of Tokyo was examined by immunohistochemistry. Their clinicopathological features and prognosis were also reviewed. Approximately 60% of MGT tissues showed sLe(x) positive expressions, while all normal mammary gland tissues were negative. However, its expression was not correlated with clinicopathological features and prognosis significantly. This study suggests that sLe(x) may be a tumor-associated antigen in canine and feline MGTs.

Effect of natural and synthetic retinoids on the proliferation and differentiation of three canine melanoma cell lines.

The effect of two natural retinoids and synthetic retinoids with or without retinoid synergists on the proliferation and differentiation of 3 melanoma cell lines were investigated in vitro. No retinoids showed significant growth inhibitory effect on these cell lines when used alone, however, cell differentiation and significant growth inhibition were observed when treated with a combination of retinoids and a retinoid synergist. This study may suggest that, though the cells showed low susceptibilities when retinoids were treated alone, the combination of retinoids and a retinoid synergist may be effective to control the growth of canine melanoma cell lines.