1
|
Uemura KI, Togo A, Hiroshige T, Ohta K, Ueda K, Nishihara K, Nakiri M, Hirashima S, Igawa T, Nakamura KI. Three-dimensional ultrastructural and anatomical analysis of prostatic neuroendocrine cells in mice. Prostate 2024; 84:866-876. [PMID: 38590054 DOI: 10.1002/pros.24705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 03/11/2024] [Accepted: 03/25/2024] [Indexed: 04/10/2024]
Abstract
BACKGROUND A few studies have examined the ultrastructure of prostatic neuroendocrine cells (NECs), and no study has focused on their ultrastructure in three dimensions. In this study, three-dimensional ultrastructural analysis of mouse prostatic NECs was performed to clarify their anatomical characteristics. METHODS Three 13-week-old male C57BL/6 mice were deeply anesthetized, perfused with physiological saline and 2% paraformaldehyde, and then placed in 2.5% glutaraldehyde in 0.1 M cacodylate (pH 7.3) buffer for electron microscopy. After perfusion, the lower urinary tract, which included the bladder, prostate, coagulation gland, seminal vesicle, upper vas deferens, and urethra, was removed, and the specimen was cut into small cubes and subjected to postfixation and en bloc staining. Three-dimensional ultrastructural analysis was performed on NECs, the surrounding cells, tissues, and nerves using focused ion beam/scanning electron microscope tomography. RESULTS Twenty-seven serial sections were used in the present study, and 32 mouse prostatic NECs were analyzed. Morphologically, the NECs could be classified into three types: flask, flat, and closed. Closed-shaped NECs were always adjacent to flask-shaped cells. The flask-shaped and flat NECs were in direct contact with the ductal lumen and always had microvilli at their contact points. Many of the NECs had accompanying nerves, some of which terminated on the surface in contact with the NEC. CONCLUSIONS Three-dimensional ultrastructural analysis of mouse prostatic NECs was performed. These cells can be classified into three types based on shape. Novel findings include the presence of microvilli at their points of contact with the ductal lumen and the presence of accompanying nerves.
Collapse
Affiliation(s)
- Kei-Ichiro Uemura
- Department of Urology, Kurume University School of Medicine, Kurume, Japan
| | - Akinobu Togo
- Advanced Imaging Research Center, Kurume University School of Medicine, Kurume, Japan
| | - Tasuku Hiroshige
- Department of Urology, Kurume University School of Medicine, Kurume, Japan
| | - Keisuke Ohta
- Advanced Imaging Research Center, Kurume University School of Medicine, Kurume, Japan
| | - Kosuke Ueda
- Department of Urology, Kurume University School of Medicine, Kurume, Japan
| | - Kiyoaki Nishihara
- Department of Urology, Kurume University School of Medicine, Kurume, Japan
| | - Makoto Nakiri
- Department of Urology, Kurume University School of Medicine, Kurume, Japan
| | - Shingo Hirashima
- Dental and Oral Medical Center, Kurume University School of Medicine, Kurume, Japan
| | - Tsukasa Igawa
- Department of Urology, Kurume University School of Medicine, Kurume, Japan
| | - Kei-Ichiro Nakamura
- Advanced Imaging Research Center, Kurume University School of Medicine, Kurume, Japan
| |
Collapse
|
2
|
Wang H, He K, Cheng CK. The Structure, Biology, and Mechanical Function of Tendon/Ligament-Bone Interfaces. TISSUE ENGINEERING. PART B, REVIEWS 2024. [PMID: 38323564 DOI: 10.1089/ten.teb.2023.0295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
After tendon or ligament reconstruction, the interface between the hard bone and soft connective tissue is considerably weakened and is difficult to restore through healing. The tendon/ligament-bone interface is mechanically the weakest point under tensile loading and is often the source of various postoperative complications, such as bone resorption and graft laxity. A comprehensive understanding of the macro- and microfeatures of the native tendon/ligament-bone interface would be beneficial for developing strategies for regenerating the tissue. This article discusses the structural, biological, and mechanical features of the tendon/ligament-bone interfaces and how these can be affected by aging and loading conditions.
Collapse
Affiliation(s)
- Huizhi Wang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
- Engineering Research Center for Digital Medicine of the Ministry of Education, Shanghai Jiao Tong University, Shanghai, China
- Center for Intelligent Medical Equipment and Devices, Institute for Innovative Medical Devices, University of Science and Technology of China, Hefei, China
- Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou, China
| | - Kaixin He
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
- Engineering Research Center for Digital Medicine of the Ministry of Education, Shanghai Jiao Tong University, Shanghai, China
| | - Cheng-Kung Cheng
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
- Engineering Research Center for Digital Medicine of the Ministry of Education, Shanghai Jiao Tong University, Shanghai, China
| |
Collapse
|
3
|
Yamada T, Kanazawa T, Ohta K, Nakamura KI. Comparison of Structural Properties Between Postnatal and Adult Tendon Insertion with FIB/SEM Tomography in Rat. Kurume Med J 2021; 66:217-224. [PMID: 34690208 DOI: 10.2739/kurumemedj.ms664007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVE The repaired tendon-bone interface after rotator cuff (RC) repair has been identified as a mechanical weak point, which may contribute to re-tearing. Analyzing the postnatal development of a normal tendon insertion in detail may be useful in helping to promote the regeneration of a normal tendon insertion. We verified the morphological differences between postnatal and adult tendon insertions in terms of the cellular structural properties using FIB/SEM tomography. MATERIALS AND METHOD SPostnatal and adult Sprague-Dawley rats were used as a model of tendon insertion. The morphological structure of the insertion was evaluated using hematoxylin and eosin (HE) staining, and the 3D ultrastructure of the cells in the insertion was evaluated using FIB/SEM tomography. Additionally, the volume of the cell bodies, nuclei, and cytoplasm were measured and compared in a quantitative analysis. RESULTS On conventional histology, the boundary line between the fibrocartilage and mineralized cartilage was flat in the adult insertions; however, the boundary line between the mineralized cartilage and bone formed deep interdigitations. The morphology of the cells among the collagen bundles in the adult insertions was completely different from those in the postnatal insertions at the 3D ultrastructural level. The cellular structural properties were statistically different between the postnatal and adult insertions. CONCLUSIONS In the present study, the morphological differences between postnatal and adult tendon insertion in terms of the ultrastructural cellular properties were clarified. These findings may aid in determining how to regenerate a clinically stable tendon insertion at the tendon-bone interface after RC repair.
Collapse
Affiliation(s)
- Taku Yamada
- Division of Microscopic and Development Anatomy, Department of Anatomy, Kurume University School of Medicine
| | - Tomonoshin Kanazawa
- Division of Microscopic and Development Anatomy, Department of Anatomy, Kurume University School of Medicine.,Department of Orthopaedic surgery, Kurume University School of Medicine
| | - Keisuke Ohta
- Division of Microscopic and Development Anatomy, Department of Anatomy, Kurume University School of Medicine
| | - Kei-Ichiro Nakamura
- Division of Microscopic and Development Anatomy, Department of Anatomy, Kurume University School of Medicine
| |
Collapse
|
4
|
Mizutani Y, Yamashita M, Hashimoto R, Atsugi T, Ryu A, Hayashi A, Rikimaru-Nishi Y, Ohta K. Three-dimensional structure analysis of melanocytes and keratinocytes in senile lentigo. Microscopy (Oxf) 2021; 70:224-231. [PMID: 32991711 DOI: 10.1093/jmicro/dfaa054] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 08/01/2020] [Accepted: 09/10/2020] [Indexed: 11/13/2022] Open
Abstract
Senile lentigo or age spots are hyperpigmented macules of skin that commonly develop following long-term exposure to ultraviolet radiation. This condition is caused by accumulation of large numbers of melanosomes (melanin granules) produced by melanocytes within neighboring keratinocytes. However, there is still no consensus regarding the melanosome transfer mechanism in senile lentigo. To date, most pathohistological studies of skin have been two-dimensional and do not provide detailed data on the complex interactions of the melanocyte-keratinocyte network involved in melanosome transfer. We performed a three-dimensional reconstruction of the epidermal microstructure in senile lentigo using three different microscopic modalities to visualize the topological melanocyte-keratinocyte relationship and melanosome distribution. Confocal laser microscopy images showed that melanocyte dendritic processes are more frequently branched and elongated in senile lentigo skin than in normal skin. Serial transmission electron micrographs showed that dendritic processes extend into intercellular spaces between keratinocytes. Focused ion beam-scanning electron micrographs showed that dendritic processes in senile lentigo encircle adjacent keratinocytes and accumulate large numbers of melanosomes. Moreover, melanosomes transferred to keratinocytes are present not only in the supranuclear area but throughout the perinuclear area except on the basal side. The use of these different microscopic methods helped to elucidate the three-dimensional morphology and topology of melanocytes and keratinocytes in senile lentigo. We show that the localization of melanosomes in dendritic processes to the region encircling recipient keratinocytes contributes to efficient melanosome transfer in senile lentigo.
Collapse
Affiliation(s)
- Yuki Mizutani
- Research Laboratories, KOSÉ Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan
| | - Mika Yamashita
- Research Laboratories, KOSÉ Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan
| | - Rie Hashimoto
- Research Laboratories, KOSÉ Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan
| | - Toru Atsugi
- Research Laboratories, KOSÉ Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan
| | - Akemi Ryu
- Research Laboratories, KOSÉ Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan
| | - Akinobu Hayashi
- Research Laboratories, KOSÉ Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo, 114-0005 Japan
| | - Yukiko Rikimaru-Nishi
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, 830-0011 Japan.,Department of Plastic and Reconstructive Surgery, and Maxillofacial Surgery, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka, 830-0011, Japan
| | - Keisuke Ohta
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, 830-0011 Japan
| |
Collapse
|
5
|
Walters M, Crew M, Fyfe G. Bone Surface Micro‐Topography at Craniofacial Entheses: Insights on Osteogenic Adaptation at Muscle Insertions. Anat Rec (Hoboken) 2019; 302:2140-2155. [DOI: 10.1002/ar.24215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 02/04/2019] [Accepted: 03/06/2019] [Indexed: 12/19/2022]
Affiliation(s)
- Mark Walters
- School of Human SciencesThe University of Western Australia Crawley Perth Western Australia
- Department of Plastic and Reconstructive SurgeryPerth Children's Hospital Nedlands Perth Western Australia
| | - Michael Crew
- Health Department of Western Australia and Faculty of Health SciencesCurtin University Western Australia
| | - Georgina Fyfe
- Faculty of Health SciencesCurtin University Perth Western Australia
| |
Collapse
|
6
|
Tanaka K, Kanazawa T, Gotoh M, Tanesue R, Nakamura H, Ohzono H, Okawa T, Shiba N. Effects of Estrogen-Deficient State on Rotator Cuff Healing. Am J Sports Med 2019; 47:389-397. [PMID: 30625277 DOI: 10.1177/0363546518815869] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Rotator cuff retears after surgical repair are a concern, despite advances in operative techniques, but few studies have investigated the effects of the estrogen-deficient state on tendon-to-bone healing at the repair site. PURPOSE We evaluated the effect of the estrogen-deficient state on tendon-to-bone healing after rotator cuff repair in an ovariectomized rat model. STUDY DESIGN Controlled laboratory study. METHODS Female Sprague Dawley rats underwent detachment and immediate repair of the supraspinatus tendon. Surgery was performed in 24 rats at 4.5 weeks of age 17 weeks after ovariectomy (OVX group) and in 24 age-matched control rats without ovariectomy (control group). Animals were sacrificed at 2, 4, 8, and 12 weeks after surgery for biomechanical and histological evaluations of reattachment. Bone mineral density (BMD) at the insertion site and cancellous bone in the humeral head was assessed by micro-computed tomography. RESULTS BMD was significantly lower both at the insertion site and in cancellous area in the OVX group than in the control group at weeks 2 to 12. Ultimate load to failure, ultimate stress, linear stiffness, and the Young modulus were significantly lower in the OVX group than in the control group at 2 and 4 weeks, but the difference was no longer significant at 8 and 12 weeks. At 2 and 4 weeks, relatively immature granulation tissue was observed in the OVX group compared with the control group. At 8 and 12 weeks after surgery, there were differences in the tendon-bone interface in the 2 groups: Direct insertion with well-established chondroid tissue was seen in the control group, and indirect insertion without chondroid tissue was seen in the OVX group. Consistently, the amount of chondroid tissue was greater and collagen organization was better in the control group than in the OVX group. Cells expressing cathepsin K were significantly more numerous both at the insertion site and in cancellous bone in the OVX group than in the control group. CONCLUSION The estrogen-deficient state by ovariectomy, compared with control rats, led to decreased biomechanical properties and poor development of chondroid tissue that influenced the repair of the tendon insertion after surgery. CLINICAL RELEVANCE Agents that modulate bone metabolism might improve tendon-to-bone healing in patients with an estrogen-deficient state, such as postmenopausal women who undergo rotator cuff surgery.
Collapse
Affiliation(s)
- Koji Tanaka
- Department of Orthopaedic Surgery, Kurume University School of Medicine, Kurume, Japan
| | - Tomonoshin Kanazawa
- Department of Orthopaedic Surgery, Kurume University School of Medicine, Kurume, Japan
| | - Masafumi Gotoh
- Department of Orthopaedic Surgery, Kurume University Medical Center, Kurume, Japan
| | - Ryo Tanesue
- Department of Orthopaedic Surgery, Kurume University School of Medicine, Kurume, Japan
| | - Hidehiro Nakamura
- Department of Orthopaedic Surgery, Kurume University Medical Center, Kurume, Japan
| | - Hiroki Ohzono
- Department of Orthopaedic Surgery, Kurume University School of Medicine, Kurume, Japan
| | - Takahiro Okawa
- Department of Orthopaedic Surgery, Kurume University Medical Center, Kurume, Japan
| | - Naoto Shiba
- Department of Orthopaedic Surgery, Kurume University School of Medicine, Kurume, Japan
| |
Collapse
|
7
|
Hirashima S, Ohta K, Kanazawa T, Okayama S, Togo A, Miyazono Y, Kusukawa J, Nakamura KI. Three-dimensional ultrastructural analysis and histomorphometry of collagen bundles in the periodontal ligament using focused ion beam/scanning electron microscope tomography. J Periodontal Res 2018; 55:23-31. [PMID: 30035304 DOI: 10.1111/jre.12592] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 06/07/2018] [Accepted: 06/13/2018] [Indexed: 12/21/2022]
Abstract
BACKGROUND AND OBJECTIVE The periodontal ligament (PDL) is an essential tissue for tooth function. However, the 3-dimensional ultrastructure of these PDL collagen bundles on a mesoscale is not clear. We investigated the 3-dimensional ultrastructure of these collagen bundles and quantitatively analyzed their histomorphometry using focused ion beam/scanning electron microscope (FIB/SEM) tomography. MATERIAL AND METHODS The PDLs of the first mandibular molar of male C57BL/6 mice were analyzed using FIB/SEM tomography. The serial images of the collagen bundles so obtained were reconstructed. The collagen bundles were analyzed quantitatively using 3-dimensional histomorphometry. RESULTS Collagen bundles of the PDL demonstrated multiple branched structures, rather than a single rope-like structure, and were wrapped in cytoplasm sheets. The structure of the horizontal fiber of the collagen bundle was an extensive meshwork. In contrast, the oblique and apical fibers of the collagen bundle showed a chain-like structure. The area and the minor and major axis lengths of cross-sections of the horizontal fiber, as determined from 3-dimensional images, were significantly different from those of the oblique and apical fibers. CONCLUSION These findings indicate that collagen bundles in horizontal fiber areas have high strength and that the tooth is firmly anchored to the alveolar bone by the horizontal fibers, but is not secured evenly to the alveolar bone. The tooth is firmly anchored around the cervical area, creating a "slingshot-like structure." This study has provided further insights into the structure of the PDL and forms the basis for the development of more effective therapies for periodontal tissue regeneration.
Collapse
Affiliation(s)
- Shingo Hirashima
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Japan.,Dental and Oral Medical Center, Kurume University School of Medicine, Kurume, Japan
| | - Keisuke Ohta
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Japan.,Advanced Imaging Research Center, Kurume University School of Medicine, Kurume, Japan
| | - Tomonoshin Kanazawa
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Japan
| | - Satoko Okayama
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Japan
| | - Akinobu Togo
- Advanced Imaging Research Center, Kurume University School of Medicine, Kurume, Japan
| | - Yoshihiro Miyazono
- Dental and Oral Medical Center, Kurume University School of Medicine, Kurume, Japan
| | - Jingo Kusukawa
- Dental and Oral Medical Center, Kurume University School of Medicine, Kurume, Japan
| | - Kei-Ichiro Nakamura
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Japan
| |
Collapse
|
8
|
Sartori J, Köhring S, Witte H, Fischer MS, Löffler M. Three-dimensional imaging of the fibrous microstructure of Achilles tendon entheses in Mus musculus. J Anat 2018; 233:370-380. [PMID: 29920671 PMCID: PMC6081500 DOI: 10.1111/joa.12837] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/09/2018] [Indexed: 12/20/2022] Open
Abstract
The whole-organ, three-dimensional microstructure of murine Achilles tendon entheses was visualized with micro-computed tomography (microCT). Contrast-enhancement was achieved either by staining with phosphotungstic acid (PTA) or by a combination of cell-maceration, demineralization and critical-point drying with low tube voltages and propagation-based phase-contrast (fibrous structure scan). By PTA-staining, X-ray absorption of the enthesial soft tissues became sufficiently high to segment the tendon and measure cross-sectional areas along its course. With the fibrous structure scans, three-dimensional visualizations of the collagen fiber networks of complete entheses were obtained. The characteristic tissues of entheses were identified in the volume data. The tendon proper was marked as a segment manually. The fibers within the tendon were marked by thresholding. Tendon and fiber cross-sectional areas were measured. The measurements were compared between individuals and protocols for contrast-enhancement, using a spatial reference system within the three-dimensional enthesis. The usefulness of the method for investigations of the fibrous structure of collagenous tissues is demonstrated.
Collapse
Affiliation(s)
- Julian Sartori
- Institut für Zoologie und EvolutionsforschungFriedrich‐Schiller‐Universität JenaJenaGermany
| | - Sebastian Köhring
- Fachgebiet BiomechatronikFakultät für Maschinenbau / IMN MacroNano®Technische Universität IlmenauIlmenauGermany
| | - Hartmut Witte
- Fachgebiet BiomechatronikFakultät für Maschinenbau / IMN MacroNano®Technische Universität IlmenauIlmenauGermany
| | - Martin S. Fischer
- Institut für Zoologie und EvolutionsforschungFriedrich‐Schiller‐Universität JenaJenaGermany
| | - Markus Löffler
- Dresden Center for Nanoanalysis (DCN)Center for Advancing Electronics Dresden (cfaed)Technische Universität DresdenDresdenGermany
| |
Collapse
|
9
|
Koga D, Kusumi S, Watanabe T. Backscattered electron imaging of resin-embedded sections. Microscopy (Oxf) 2018; 67:5038522. [PMID: 29920601 DOI: 10.1093/jmicro/dfy028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 05/23/2018] [Indexed: 02/28/2024] Open
Abstract
Scanning electron microscopes have longer focal depths than transmission electron microscopes and enable visualization of the three-dimensional (3D) surface structures of specimens. While scanning electron microscopy (SEM) in biological research was generally used for the analysis of bulk specimens until around the year 2000, more recent instrumental advances have broadened the application of SEM; for example, backscattered electron (BSE) signals under low accelerating voltages allow block-face and section-face images of tissues embedded in resin to be acquired. This technical breakthrough has led to the development of novel 3D imaging techniques including focused ion beam SEM, serial-block face SEM and serial section SEM. Using these new techniques, the 3D shapes of cells and cell organelles have been revealed clearly through reconstruction of serial tomographic images. In this review, we address two modern SEM techniques: section-face imaging of resin-embedded tissue samples based on BSE observations, and serial section SEM for reconstruction of the 3D structures of cells and organelles from BSE-mode SEM images of consecutive ultrathin sections on solid substrates.
Collapse
Affiliation(s)
- Daisuke Koga
- Department of Microscopic Anatomy and Cell Biology, Asahikawa Medical University, Asahikawa, Japan
| | - Satoshi Kusumi
- Division of Morphological Sciences, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Tsuyoshi Watanabe
- Department of Microscopic Anatomy and Cell Biology, Asahikawa Medical University, Asahikawa, Japan
| |
Collapse
|
10
|
Zebrafish skeleton development: High resolution micro-CT and FIB-SEM block surface serial imaging for phenotype identification. PLoS One 2017; 12:e0177731. [PMID: 29220379 PMCID: PMC5722281 DOI: 10.1371/journal.pone.0177731] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 05/02/2017] [Indexed: 12/03/2022] Open
Abstract
Although bone is one of the most studied living materials, many questions about the manner in which bones form remain unresolved, including fine details of the skeletal structure during development. In this study, we monitored skeleton development of zebrafish larvae, using calcein fluorescence, high-resolution micro-CT 3D images and FIB-SEM in the block surface serial imaging mode. We compared calcein staining of the skeletons of the wild type and nacre mutants, which are transparent zebrafish, with micro-CT for the first 30 days post fertilization embryos, and identified significant differences. We quantified the bone volumes and mineral contents of bones, including otoliths, during development, and showed that such developmental differences, including otolith development, could be helpful in identifying phenotypes. In addition, high-resolution imaging revealed the presence of mineralized aggregates in the notochord, before the formation of the first bone in the axial skeleton. These structures might play a role in the storage of the mineral. Our results highlight the potential of these high-resolution 3D approaches to characterize the zebrafish skeleton, which in turn could prove invaluable information for better understanding the development and the characterization of skeletal phenotypes.
Collapse
|
11
|
Three-dimensional ultrastructural analysis of cells in the periodontal ligament using focused ion beam/scanning electron microscope tomography. Sci Rep 2016; 6:39435. [PMID: 27995978 PMCID: PMC5171660 DOI: 10.1038/srep39435] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 11/21/2016] [Indexed: 01/29/2023] Open
Abstract
The accurate comprehension of normal tissue provides essential data to analyse abnormalities such as disease and regenerative processes. In addition, understanding the proper structure of the target tissue and its microenvironment may facilitate successful novel treatment strategies. Many studies have examined the nature and structure of periodontal ligaments (PDLs); however, the three-dimensional (3D) structure of cells in normal PDLs remains poorly understood. In this study, we used focused ion beam/scanning electron microscope tomography to investigate the whole 3D ultrastructure of PDL cells along with quantitatively analysing their structural properties and ascertaining their orientation to the direction of the collagen fibre. PDL cells were shown to be in contact with each other, forming a widespread mesh-like network between the cementum and the alveolar bone. The volume of the cells in the horizontal fibre area was significantly larger than in other areas, whereas the anisotropy of these cells was lower than in other areas. Furthermore, the orientation of cells to the PDL fibres was not parallel to the PDL fibres in each area. As similar evaluations are recognized as being challenging using conventional two-dimensional methods, these novel 3D findings may contribute necessary knowledge for the comprehensive understanding and analysis of PDLs.
Collapse
|
12
|
Novel scanning electron microscopy methods for analyzing the 3D structure of the Golgi apparatus. Anat Sci Int 2016; 92:37-49. [DOI: 10.1007/s12565-016-0380-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 10/14/2016] [Indexed: 10/20/2022]
|
13
|
Histomorphometric and ultrastructural analysis of the tendon-bone interface after rotator cuff repair in a rat model. Sci Rep 2016; 6:33800. [PMID: 27647121 PMCID: PMC5028779 DOI: 10.1038/srep33800] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 09/01/2016] [Indexed: 12/14/2022] Open
Abstract
Successful rotator cuff repair requires biological anchoring of the repaired tendon to the bone. However, the histological structure of the repaired tendon-bone interface differs from that of a normal tendon insertion. We analysed differences between the normal tendon insertion and the repaired tendon-bone interface after surgery in the mechanical properties, histomorphometric analysis, and 3-dimensional ultrastructure of the cells using a rat rotator cuff repair model. Twenty-four adult Sprague-Dawley (SD) rats underwent complete cuff tear and subsequent repair of the supraspinatus tendon. The repaired tendon-bone interface was evaluated at 4, 8, and 12 weeks after surgery. At each time point, shoulders underwent micro-computed tomography scanning and biomechanical testing (N = 6), conventional histology and histomorphometric analysis (N = 6), and ultrastructural analysis with focused ion beam/scanning electron microscope (FIB/SEM) tomography (N = 4). We demonstrated that the cellular distribution between the repaired tendon and bone at 12 weeks after surgery bore similarities to the normal tendon insertion. However, the ultrastructure of the cells at any time point had a different morphology than those of the normal tendon insertion. These morphological differences affect the healing process, partly contributing to re-tearing at the repair site. These results may facilitate future studies of the regeneration of a normal tendon insertion.
Collapse
|