| 1. |
- Bougas, Kostas, et al.
(författare)
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Bone apposition to laminin-1 coated implants : Histologic and 3D evaluation
- 2013
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Ingår i: International Journal of Oral and Maxillofacial Surgery. - : Elsevier BV. - 0901-5027 .- 1399-0020. ; 42:5, s. 677-682
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Tidskriftsartikel (refereegranskat)abstract
- Laminin-1 has been reported as one of the factors responsible for the nucleation of calcium phosphates and, in vitro, has been reported to selectively recruit osteoprogenitors. This article focused on its in vivo effects, and evaluated the effect of laminin-1 local application on osseointegration. Polished cylindrical hydroxyapatite implants were coated with laminin-1 (test) and the bone responses in the rabbit tibiae after 2 and 4 weeks were evaluated and compared to the non-coated implants (control). Before the samples were processed for histological sectioning, they were three-dimensionally analysed with micro computed tomography (μCT). Both evaluation methods were analysed with regards to bone area around the implant and bone to implant contact. From the histologic observation, new bone formation around the laminin-1 coated implant at 2 weeks seemed to have increased the amount of supporting bone around the implant, however, at 4 weeks, the two groups presented no notable differences. The two-dimensional and three-dimensional morphometric evaluation revealed that both histologic and three-dimensional analysis showed some tendency in favour of the test group implants, however there was no statistical significance between the test and control group results.
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| 2. |
- Doi, Daisuke, et al.
(författare)
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Isolation of human induced pluripotent stem cell-derived dopaminergic progenitors by cell sorting for successful transplantation.
- 2014
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Ingår i: Stem Cell Reports. - : Elsevier BV. - 2213-6711. ; 2:3, s. 337-350
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Tidskriftsartikel (refereegranskat)abstract
- Human induced pluripotent stem cells (iPSCs) can provide a promising source of midbrain dopaminergic (DA) neurons for cell replacement therapy for Parkinson's disease. However, iPSC-derived donor cells inevitably contain tumorigenic or inappropriate cells. Here, we show that human iPSC-derived DA progenitor cells can be efficiently isolated by cell sorting using a floor plate marker, CORIN. We induced DA neurons using scalable culture conditions on human laminin fragment, and the sorted CORIN(+) cells expressed the midbrain DA progenitor markers, FOXA2 and LMX1A. When transplanted into 6-OHDA-lesioned rats, the CORIN(+) cells survived and differentiated into midbrain DA neurons in vivo, resulting in significant improvement of the motor behavior, without tumor formation. In particular, the CORIN(+) cells in a NURR1(+) cell-dominant stage exhibited the best survival and function as DA neurons. Our method is a favorable strategy in terms of scalability, safety, and efficiency and may be advantageous for clinical application.
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| 3. |
- Jimbo, Ryo, 1979, et al.
(författare)
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Accelerated photo-induced hydrophilicity promotes osseointegration: an animal study.
- 2011
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Ingår i: Clinical implant dentistry and related research. - : Wiley. - 1708-8208 .- 1523-0899. ; 13:1, s. 79-85
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Tidskriftsartikel (refereegranskat)abstract
- In the previous in vitro study, fluoride-modified, anodized porous titanium was proven to have enhanced its photo-induced hydrophilicity, which induced the hyperactivation of initial cell response.
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| 4. |
- Jimbo, Ryo, 1979, et al.
(författare)
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Histological and three-dimensional evaluation of osseointegration to nanostructured calcium phosphate-coated implants.
- 2011
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Ingår i: Acta biomaterialia. - : Elsevier BV. - 1878-7568 .- 1742-7061.
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Tidskriftsartikel (refereegranskat)abstract
- Nanostructures on implant surfaces have been shown to enhance osseointegration; however, commonly used evaluation techniques are probably not sufficiently sensitive to fully determine the effects of this process. This study aimed to observe the osseointegration properties of nanostructured calcium phosphate (CaP)-coated implants, by using a combination of three-dimensional imaging and conventional histology. Titanium implants were coated with stable CaP nanoparticles using an immersion technique followed by heat treatment. Uncoated implants were used as the control. After topographical and chemical characterizations, implants were inserted into the rabbit femur. After 2 and 4weeks, the samples were retrieved for micro-computed tomography and histomorphometric evaluation. Scanning electron microscopy evaluation indicated that the implant surface was modified at the nanoscale by CaP to obtain surface textured with rod-shaped structures. Relative to the control, the bone-to-implant contact for the CaP-coated implant was significantly higher at 4weeks after the implant surgery. Further, corresponding 3-D images showed active bone formation surrounding the implant. 3-D quantification and 2-D histology demonstrated statistical correlation; moreover, 3-D quantification indicated a statistical decrease in bone density in the non-coated control implant group between 2 and 4weeks after the surgery. The application of 3-D evaluation further clarified the temporal characteristics and biological reaction of implants in bone.
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| 5. |
- Jimbo, Ryo, et al.
(författare)
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Nano Hydroxyapatite-coated Implants Improve Bone Nanomechanical Properties
- 2012
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Ingår i: Journal of Dental Research. - : SAGE Publications. - 0022-0345 .- 1544-0591. ; 91:12, s. 1172-1177
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Tidskriftsartikel (refereegranskat)abstract
- Nanostructure modification of dental implants has long been sought as a means to improve osseointegration through enhanced biomimicry of host structures. Several methods have been proposed and demonstrated for creating nanotopographic features; here we describe a nanoscale hydroxyapatite (HA)-coated implant surface and hypothesize that it will hasten osseointegration and improve its quality relative to that of non-coated implants. Twenty threaded titanium alloy implants, half prepared with a stable HA nanoparticle surface and half grit-blasted, acid-etched, and heat-treated (HT), were inserted into rabbit femurs. Pre-operatively, the implants were morphologically and topographically characterized. After 3 weeks of healing, the samples were retrieved for histomorphometry. The nanomechanical properties of the surrounding bone were evaluated by nanoindentation. While both implants revealed similar bone-to-implant contact, the nanoindentation demonstrated that the tissue quality was significantly enhanced around the HA-coated implants, validating the postulated hypothesis.
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| 6. |
- Ono, Daisuke, et al.
(författare)
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Lateral bone augmentation with newly developed β-tricalcium phosphate block: an experimental study in the rabbit mandible.
- 2011
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Ingår i: Clinical oral implants research. - : Wiley. - 1600-0501 .- 0905-7161.
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To evaluate the biological effects of newly developed β-tricalcium phosphate (β-TCP) to improve lateral bone augmentation. Material and methods: Test samples (rod-shaped [RS]-blocks) were prepared through hydrothermal processing α-TCPs. As controls, commercially available β-TCPs (C-blocks; Osferion) were used. The blocks were placed onto the rabbit mandibles (n=5/group, mean: 4kg). Samples were retrieved after 6, 12 and 24 weeks. Thereafter, the sections were evaluated for histological and histomorphometric analyses. The parameters set were: BV/TV (%): [(area of newly formed bone; area-NFB)/(whole measured area; WA)] × 100, BV+Imp.V/TV (%): [(area-NFB+area of remaining β-TCP block)/WA] × 100, N.Oc/I.Pm: (osteoclast number)/(entire β-TCP block perimeter; 100mm). Results: BV/TV of the C-blocks (10.71±3.39%) was significantly higher than the RS-blocks (3.5±3.52%, P<0.05) at 6 weeks. At 24 weeks, the RS-blocks (23.66±2.7%) showed significantly higher values than the C-blocks (13.23±2.65%, P<0.001). The BV+Imp.V/TV of the RS-blocks was significantly higher than that of the C-block group (29.61±5.84% and 19.13±3.14%), maintaining high values between 6 and 24 weeks (44.16±5.19% and 50.88±4%, P<0.001). The N.Oc/I.Pm values were significantly greater in the RS-block group than in the C-block group throughout the observation period (P<0.05). Conclusions: The newly developed β-TCP blocks presented subsequent replacement by newly formed bone, in conjunction with maintaining the external morphology. To cite this article: Ono D, Jimbo R, Kawachi G, Ioku K, Ikeda T, Sawase T. Lateral bone augmentation with newly developed β-tricalcium phosphate block: an experimental study in the rabbit mandible. Clin. Oral Impl. Resxx, 2011; 000-000.
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| 7. |
- Perkiö Kato, Naoko, 1980-, et al.
(författare)
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Quality of Life and Influential Factors in Patients Implanted With a Left Ventricular Assist Device
- 2015
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Ingår i: Circulation Journal. - : JAPANESE CIRCULATION SOC. - 1346-9843 .- 1347-4820. ; 79:10, s. 2186-2192
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Tidskriftsartikel (refereegranskat)abstract
- Background: Improving quality of life (QOL) has become an important goal in left ventricular assist device (LVAD) therapy. We aimed (1) to assess the effect of an implantable LVAD on patients QOL, (2) to compare LVAD patients QOL to that of patients in different stages of heart failure (HF), and (3) to identify factors associated with patients QOL.Methods and Results: The QOL of 33 Japanese implantable LVAD patients was assessed using the Minnesota Living with Heart Failure Questionnaire (MLHFQ) and Short-form 8 (SF-8), before and at 3 and 6 months afterwards. After LVAD implantation, QOL significantly improved [MLHFQ, SF-8 physical component score (PCS), SF-8 mental component score (MCS), all Pless than0.05]. Implanted LVAD patients had a better QOL than extracorporeal LVAD patients (n=33, 32.1 +/- 21.9 vs. n=17, 47.6 +/- 18.2), and Stage D HF patients (n=32, 51.1 +/- 17.3), but the score was comparable to that of patients who had undergone a heart transplant (n=13). In multiple regression analyses, postoperative lower albumin concentration and right ventricular failure were independently associated with poorer PCS. Female sex and postoperative anxiety were 2 of the independent factors for poorer MCS (all Pless than0.05).Conclusions: Having an implantable LVAD improves patients QOL, which is better than that of patients with an extracorporeal LVAD. Both clinical and psychological factors are influence QOL after LVAD implantation.
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| 8. |
- Schwartz Filho, Humberto Osvaldo, et al.
(författare)
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The effect of laminin-1-doped nanoroughened implant surfaces : gene expression and morphological evaluation
- 2012
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Ingår i: International Journal of Biomaterials. - : Hindawi Publishing Corporation. - 1687-8787 .- 1687-8795. ; 2012
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Tidskriftsartikel (refereegranskat)abstract
- Aim. This study aimed to observe the morphological and molecular effect of laminin-1 doping to nanostructured implant surfaces in a rabbit model. Materials and Methods. Nanostructured implants were coated with laminin-1 (test; dilution, 100 μg/mL) and inserted into the rabbit tibiae. Noncoated implants were used as controls. After 2 weeks of healing, the implants were removed and subjected to morphological analysis using scanning electron microscopy (SEM) and gene expression analysis using the real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Results. SEM revealed bony tissue attachment for both control and test implants. Real-time RT-PCR analysis showed that the expression of osteoblast markers RUNX-2, osteocalcin, alkaline phosphatase, and collagen I was higher (1.62-fold, 1.53-fold, 1.97-fold, and 1.04-fold, resp.) for the implants modified by laminin-1 relative to the control. All osteoclast markers investigated in the study presented higher expression on the test implants than controls as follows: tartrate-resistant acid phosphatase (1.67-fold), calcitonin receptor (1.35-fold), and ATPase (1.25-fold). The test implants demonstrated higher expression of inflammatory markers interleukin-10 (1.53-fold) and tumour necrosis factor-α (1.61-fold) relative to controls. Conclusion. The protein-doped surface showed higher gene expression of typical genes involved in the osseointegration cascade than the control surface.
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| 9. |
- Vandeweghe, Stefan, et al.
(författare)
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Comparison of histological and three-dimensional characteristics of porous titanium granules and deproteinized bovine particulate grafts used for sinus floor augmentation in humans : a pilot study
- 2013
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Ingår i: Implant Dentistry. - : Lamy, Wolters Kluwer. - 1056-6163 .- 1538-2982. ; 22:4, s. 339-343
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: Slow-resorbing deproteinized bovine bone grafts have presented high success rates when used for sinus augmentation. However, histologic evaluation shows that this material is eventually excreted as a result of a foreign body reaction. The purpose of this study was to compare and to evaluate the performance of a recently introduced particulate porous graft material, consisting of pure titanium granule (PTG) to the deproteinized bovine bone grafts, when used as a sinus augmentation material. MATERIALS AND METHODS: To understand the histological aspects of PTG, deproteinized bovine particulates (Bio-Oss) and PTG were placed contralaterally as sinus grafting materials in 2 patients. After 9 months, biopsies were performed for histologic and 3-dimensional analysis. RESULTS: Both materials were in contact with newly formed bone. The Bio-Oss showed signs of foreign body reaction. In contrast, bone filled the space between the single PTG particulates, and no foreign body reaction was observed. CONCLUSIONS: From a bone formation perspective, PTG grafts were comparable with the commonly used Bio-Oss grafts and may be regarded as a possible alternative for permanent grafting in sinus augmentation.
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| 10. |
- Yabuta, Hikaru, et al.
(författare)
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Macromolecular organic matter in samples of the asteroid (162173) Ryugu
- 2023
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Ingår i: Science. - : American Association for the Advancement of Science. - 0036-8075 .- 1095-9203. ; 379:6634
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Tidskriftsartikel (refereegranskat)abstract
- Samples of the carbonaceous asteroid (162173) Ryugu were collected and brought to Earth by the Hayabusa2 spacecraft. We investigated the macromolecular organic matter in Ryugu samples and found that it contains aromatic and aliphatic carbon, ketone, and carboxyl functional groups. The spectroscopic features of the organic matter are consistent with those in chemically primitive carbonaceous chondrite meteorites that experienced parent-body aqueous alteration (reactions with liquid water). The morphology of the organic carbon includes nanoglobules and diffuse carbon associated with phyllosilicate and carbonate minerals. Deuterium and/or nitrogen-15 enrichments indicate that the organic matter formed in a cold molecular cloud or the presolar nebula. The diversity of the organic matter indicates variable levels of aqueous alteration on Ryugus parent body.
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