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Adult Endogenous Dopaminergic Neuroregeneration Against Parkinson's Disease: Ideal Animal Models?

Vijayanathan Y, Lim SM, Tan MP, Lim FT, Majeed ABA, Ramasamy K

Neurotox Res, 2021 Apr;39(2):504-532.
PMID: 33141428 DOI: 10.1007/s12640-020-00298-7

Parkinson's disease (PD) is the second most common neurodegenerative disease. The etiology of PD remains an enigma with no available disease modifying treatment or cure. Pharmacological compensation is the only quality of life improving treatments available. Endogenous dopaminergic neuroregeneration has recently been considered a plausible therapeutic strategy for PD. However, researchers have to first decipher the complexity of adult endogenous neuroregeneration. This raises the need of animal models to understand the underlying molecular basis. Mammalian models with highly conserved genetic homology might aid researchers to identify specific molecular mechanisms. However, the scarcity of adult neuroregeneration potential in mammals obfuscates such investigations. Nowadays, non-mammalian models are gaining popularity due to their explicit ability to neuroregenerate naturally without the need of external enhancements, yet these non-mammals have a much diverse gene homology that critical molecular signals might not be conserved across species. The present review highlights the advantages and disadvantages of both mammalian and non-mammalian animal models that can be essentially used to study the potential of endogenous DpN regeneration against PD.

Matched MeSH terms: Nerve Regeneration
Bone regeneration at the distal aspect of the adjacent second molar after lower third molar coronectomy: a long-term analysis

Leung YY, Yeung AWK, Ismail IN, Wong NSM

Int J Oral Maxillofac Surg, 2020 Oct;49(10):1360-1366.
PMID: 32340909 DOI: 10.1016/j.ijom.2020.03.016

A residual bone defect at the distal aspect of the adjacent second molar may occur after total removal of the lower third molar. Lower third molar coronectomy has been proved to be a safe alternative to total removal, but the extent of bone regeneration at the adjacent tooth after coronectomy is not well reported. The aim of this prospective study was to investigate the long-term bone regeneration at the distal aspect of the adjacent second molar after lower third molar coronectomy. Preoperative and postoperative cone beam computed tomography scans were measured to assess bone regeneration at the distobuccal (DB), mid-distal (MD), and distolingual (DL) aspects of the lower second molar. Forty-eight coronectomies in 37 patients (23 female) with a mean±standard deviation age of 29.1±7.2 years were assessed. The mean follow-up was 93.2±8.7 months. The mean bone level increase at DB, MD, and DL aspects was 3.2±1.6mm, 3.5±1.5mm, and 3.2±1.6mm, respectively; the bone levels were significantly higher than the preoperative measurements (P<0.001). Age and impaction patterns were not factors affecting bone regeneration. Based on this study, it appears that coronectomy of the lower third molar brings favourable bone regeneration at the distal aspect of the adjacent second molar.

Matched MeSH terms: Bone Regeneration
A new approach for better anterior esthetic using platelet-rich fibrin as sole graft material combined with ovate design dental bridge

Buzayan MM, Mahdey HM, Ning CJ

J Indian Prosthodont Soc, 2020 04 07;20(2):219-223.
PMID: 32655228 DOI: 10.4103/jips.jips_264_19

Alveolar ridge deficiency is considered a major esthetic limitation, especially in the maxillary anterior region. Several approaches have been developed to enhance and increase the soft-tissue volume. Among those approaches are connective tissue grafts, platelet-rich fibrin (PRF) membrane and implying the guided bone regeneration concept. The PRF grafting technique was employed in this clinical case to improve and enhance the anterior esthetic without the need for the bone graft and augmentation. This article describes the use of PRF as a sole grafting material for both socket and soft-tissue augmentation for a 23-year-old male, who had an accident 8 years ago while he was playing a basketball, which caused his upper front teeth to be intruded and discolored. The upper left central tooth suffered a major external root resorption; hence, it was extracted. PRF was prepared and packed in and extruded out of the socket. This was combined with ovate design provisional bridge. Ten days, 1 month, 3 months, and 6 months postoperative review showed a significantly well-progressed healing. According to the encouraging result obtained in this clinical case in regard to tissue healing and esthetic, the PRF can be a potential sole graft material for small anterior deficient areas. This may reduce the need of bone augmentation and graft in such selected cases.

Matched MeSH terms: Bone Regeneration
Oxygen-Releasing Scaffolds for Accelerated Bone Regeneration

Touri M, Moztarzadeh F, Abu Osman NA, Dehghan MM, Brouki Milan P, Farzad-Mohajeri S, et al.

ACS Biomater Sci Eng, 2020 05 11;6(5):2985-2994.
PMID: 33463293 DOI: 10.1021/acsbiomaterials.9b01789

Hypoxia, the result of disrupted vasculature, can be categorized in the main limiting factors for fracture healing. A lack of oxygen can cause cell apoptosis, tissue necrosis, and late tissue healing. Remedying hypoxia by supplying additional oxygen will majorly accelerate bone healing. In this study, biphasic calcium phosphate (BCP) scaffolds were fabricated by robocasting, an additive manufacturing technique. Then, calcium peroxide (CPO) particles, as an oxygen-releasing agent, were coated on the BCP scaffolds. Segmental radial defects with the size of 15 mm were created in rabbits. Uncoated and CPO-coated BCP scaffolds were implanted in the defects. The empty (control) group received no implantation. Repairing of the bone was investigated via X-ray, histological analysis, and biomechanical tests at 3 and 6 months postoperatively, with immunohistochemical examinations at 6 months after operation. According to the radiological observations, formation of new bone was augmented at the interface between the implant and host bone and internal pores of CPO-coated BCP scaffolds compared to uncoated scaffolds. Histomorphometry analysis represented that the amount of newly formed bone in the CPO-coated scaffold was nearly two times higher than the uncoated one. Immunofluorescence staining revealed that osteogenic markers, osteonectin and octeocalcin, were overexpressed in the defects treated with the coated scaffolds at 6 months of postsurgery, demonstrating higher osteogenic differentiation and bone mineralization compared to the uncoated scaffold group. Furthermore, the coated scaffolds had superior biomechanical properties as in the case of 3 months after surgery, the maximal flexural force of the coated scaffolds reached to 134 N, while it was 92 N for uncoated scaffolds. The results could assure a boosted ability of bone repair for CPO-coated BCP scaffolds implanted in the segmental defect of rabbit radius because of oxygen-releasing coating, and this system of oxygen-generating coating/scaffold might be a potential for accelerated repairing of bone defects.

Matched MeSH terms: Bone Regeneration
The process-based stand growth model Formix 3-Q applied in a GIS environment for growth and yield analysis in a tropical rain forest

Ditzer T, Glauner R, Förster M, Köhler P, Huth A

Tree Physiol, 2000 Mar;20(5_6):367-381.
PMID: 12651452

Managing tropical rain forests is difficult because few long-term field data on forest growth and the impact of harvesting disturbance are available. Growth models may provide a valuable tool for managers of tropical forests, particularly if applied to the extended forest areas of up to 100,000 ha that typically constitute the so-called forest management units (FMUs). We used a stand growth model in a geographic information system (GIS) environment to simulate tropical rain forest growth at the FMU level. We applied the process-based rain forest growth model Formix 3-Q to the 55,000 ha Deramakot Forest Reserve (DFR) in Sabah, Malaysia. The FMU was considered to be composed of single and independent small-scale stands differing in site conditions and forest structure. Field data, which were analyzed with a GIS, comprised a terrestrial forest inventory, site and soil analyses (water, nutrients, slope), the interpretation of aerial photographs of the present vegetation and topographic maps. Different stand types were determined based on a classification of site quality (three classes), slopes (four classes), and present forest structure (four strata). The effects of site quality on tree allometry (height-diameter curve, biomass allometry, leaf area) and growth (increment size) are incorporated into Formix 3-Q. We derived allometric relations and growth factors for different site conditions from the field data. Climax forest structure at the stand level was shown to depend strongly on site conditions. Simulated successional pattern and climax structure were compared with field observations. Based on the current management plan for the DFR, harvesting scenarios were simulated for stands on different sites. The effects of harvesting guidelines on forest structure and the implications for sustainable forest management at Deramakot were analyzed. Based on the stand types and GIS analysis, we also simulated undisturbed regeneration of the logged-over forest in the DFR at the FMU level. The simulations predict slow recovery rates, and regeneration times far exceeding 100 years.

Matched MeSH terms: Regeneration
In vitro propagation of taro, with spermine, arginine and ornithine : II. Plantlet regeneration via callus

Sabapathy S, Nair H

Plant Cell Rep, 1995 May;14(8):520-4.
PMID: 24185524 DOI: 10.1007/BF00232787

Regeneration of plantlets from shoot apex-derived callus and "calloid" cultures of a local taro [Colocasia esculenta var. antiquorum cv. Keladi Birah] cultivar, was expedited by treatment with high levels of spermine. The total time taken, from culture of primary shoot apices on modified Linsmaier and Skoog medium supplemented with trichlorophenoxyacetic acid and kinetin, to complete plantlet regeneration, was reduced by 2-16 weeks, when the callus and "calloid" cultures were treated with 0.01, 0.1 and 1 mM spermine. Furthermore, the number of plantlets produced per gram callus increased from 25 to 55. On media supplemented with arginine and ornithine, no callus was initiated from expiants and no plantlets differentiated from pre-established callus.

Matched MeSH terms: Regeneration
In vitro propagation of taro, with spermine, arginine, and ornithine : I. Plantlet regeneration from primary shoot apices and axillary buds

Sabapathy S, Nair H

Plant Cell Rep, 1992 Jun;11(5-6):290-4.
PMID: 24203142 DOI: 10.1007/BF00235084

In vitro growth and multiplication of taro [Colocasia esculenta var. antiquorum cv. Keladi Birah] was improved considerably, when primary shoot apices were cultured on two modifications of Linsmaier and Skoog [1965] medium, containing 5.5 mg 1(-1) naphthaleneacetic acid and 0.2 mg 1(-1) kinetin or 1.85 mg 1(-1) naphthaleneacetic acid and 2 mg 1(-1) kinetin and supplemented with 10(-4) or 10(-3) mol·1(-1) of polyamine spermine or either of the precursors of polyamine putrescine-arginine and ornithine. Plantlets were regenerated directly from primary shoot apices, axillary buds and protocorm-like bodies [PLB]. Frequency of plantlet regeneration, rate of development and growth in height of main plantlets were enhanced by the addition of arginine and ornithine to the media. Secondary plantlet formation from axillary buds and PLB were promoted by spermine and arginine respectively.

Matched MeSH terms: Regeneration
Fulltext Regenerative endodontics: a review

Kundabala, M., Shetty, Neeta, Parolia, Abhishek

Malaysian Dental Journal, 2010;31(2):94-0.
MyJurnal

Tissue regeneration is a rapidly growing field providing a beacon of hope in the field of restorative and endodontics. Root canal treatment involves the removal of pulp tissue and replacement by an inorganic materials where as regenerative endodontics deals with replacement with healthy pulp to revitalize the teeth .Research in the field of tissue engineering and material science have lead to significant progress but still is plague with lots of drawbacks and failures, hence it is still not being adapted as routine clinical procedures .The purpose of this article is to review the advances made in regenerative endodontics and the future scopes.

Matched MeSH terms: Regeneration
Fulltext Recent advance s in pathophysiology and pharmacotherapy of glaucoma

Agarwal R

Medical Health Reviews, 2009;2009(1):75-93.
MyJurnal

Glaucoma, recognized as optic neuropathy is the second largest cause of blindness worldwide. The disease is characterized by progressive loss of retinal ganglion cells and visual field defects. The pathophysiological factors involved in the onset and progression of glaucoma are not fully understood. However, it is now well accepted that elevated intraocular pressure is not the only causative factor. The pathophysiology of glaucoma involves multiple factors that interact in a highly complex manner to favor development of glaucomatous optic neuropathy. As the knowledge of molecular mechanisms involved is expanding, more and more therapeutic targets are being recognized for the development of safe and effective pharmacotherapy of glaucoma. Although at present the intraocular pressure lowering drugs are still the first line of treatment, the prospect of introducing neuroprotective therapies that can directly protect and perhaps stimulate regeneration of dying and dead retinal ganglion cells, shows considerable promise. This review presents recent developments in the pathophysiology and pharmacotherapy of glaucoma.

Matched MeSH terms: Regeneration
Fulltext Studies on the effectiveness of acute gamma and ion beam irradiation in generating flower colour mutation for chrysanthemum morifolium

Shakinah Salleh, Affrida Abu Hassan, Shuhaimi Shamsudin, Yahya Awang, Ab. Kahar Sandrang, Abdullah, Thohirah Lee

Jurnal Sains Nuklear Malaysia, 2012;24(2):59-70.
MyJurnal

Chrysanthemum morfolium is an important temperate cut flower and potted plant for Malaysian local market and exporter. Considering chrysanthemum as a popular vegetatively propagated ornamental plant, induce mutations for breeding purposes are more beneficial. Several of physical mutagens have been used in mutation breeding including x-rays, gamma rays and ion beams. Gamma rays and ion beams are from two different linear energy transfer (LET) which are low and high, respectively. The objective of this study was to compare the effectiveness of acute gamma and ion beam irradiation in generating flower colour mutations on nodal explants of Chrysanthemum morifblium cv. Reagan Red'. The nodal explants were irradiated with acute gamma (0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110 and 120 Gy) and ion beam (0, 0.5, 1.0, 2.0, 3.0, 5.0, 8.0, 10, 15, 20 and 30 Gy). The optimal dose for in vitro shoot regeneration using acute gamma was in the range of 10 to .15.0Gy and for ion beam was between 3.5 to 4.OGv. Relative biological effectiveness for ion beam was found 3.75 higher than the acute gamma. The regenerated plantlets were planted in the greenhouse at MARDI, Cameron Highland for morphological screening. The highest frequency of flower colour mutation for acute gamma was 77.8% whilst for ion beam were between 42.3 to 58.3%.

Matched MeSH terms: Regeneration
Osteomyelitis in childhood -the natural history documented by radiographs

Singh, H.

Malaysian Journal of Paediatrics and Child Health, 2000;12(1):74-76.
MyJurnal

It is very rare indeed in the practice of children's orthopaedics today in Malaysia that the natural history of long bone osteomyelitis is seen. A case is presented where a shoulder abscess in a 3-year-old child developed into septic arthritis of the shoulder and subsequently chronic osteomyelitis of the adjacent humerus. The parents refused active surgical debridement and sequestrectomies. Three years later the child had regenerated a new humerus over the sequestra. Radiographs are presented illustrating the entire natural history of osteomyelitis with the regeneration of a new humerus.

Matched MeSH terms: Regeneration
Effects of salt and heat pre-treatment factors on efficient regeneration in barley (Hordeum vulgare L.)

Haque M, Islam SMS, Subramaniam S

3 Biotech, 2017 May;7(1):63.
PMID: 28452013 DOI: 10.1007/s13205-017-0675-z

An efficient callus induction and plant regeneration system has been developed using salt and heat as pre-treatment factors for three barley genotypes viz. BB-3, BB-6 and BHL-18. Different concentrations of NaCl (1.5, 2.5, 3.5, 4.5, 5.5 and 6.5 g/L) were used and its effects were determined on the basis of the viability of callus (CV), plant regeneration (PR), relative growth rate (RGR) and tolerance index (TI). The BB-6 showed highest performance on tolerance based on CV (14.72%), PR (7.69%), RGR (0.91%) and TI (0.42%) at 6.5 g/L NaCl. Various NaCl concentrations displayed significantly differences at P

Matched MeSH terms: Regeneration
Fulltext Cellular and molecular profiles of anterior nervous system regeneration in Diopatra claparedii Grube, 1878 (Annelida, Polychaeta)

Ahmad Nazri MUI, Mahmud MH, Saidi B, Mat Isa MN, Ehsak Z, Ross O, et al.

Heliyon, 2021 Feb;7(2):e06307.
PMID: 33681499 DOI: 10.1016/j.heliyon.2021.e06307

The polychaete Diopatra claparedii Grube, 1878 is among those organisms successfully carrying out full body regeneration, including the whole nervous system. Thus, D. claparedii potentially can be regarded for the nervous system regeneration (NSR) study. However, data on the property of its nervous system and the NSR profile are still lacking. In this study, we investigated the morphology of D. claparedii anterior nervous system (ANS) and examined the cellular and molecular profiles on its early anterior NSR. The nervous system of D. claparedii consists of a symmetry brain with nerves branching off, circumpharyngeal connectives that connect the brain and nerve cord as well as obvious segmental ganglia. Moreover, we identified changes in the cellular condition of the ganglionic cells in the regenerating tissue, such as the accumulation of lysosomes and lipofuscins, elongated mitochondria and multiple nucleoli. Furthermore, mRNA of tissues at two regenerating stages, as well as intact tissue (non-regenerating), were sequenced with Illumina sequencer. We identified from these tissues 37,248 sequences, 18 differential expressed proteins of which upregulated were involved in NSR with noelin-like isoform X2 turned up to be the highest being expressed. Our results highlight the cellular and molecular changes during early phase of NSR, thus providing essential insights on regeneration within Annelida and understanding the neurodegenerative diseases.

Matched MeSH terms: Regeneration
Tissue-Engineered Hydroxyapatite Bone Scaffold Impregnated with Osteoprogenitor Cells Promotes Bone Regeneration in Sheep Model

Bajuri MY, Selvanathan N, Dzeidee Schaff FN, Abdul Suki MH, Ng AMH

Tissue Eng Regen Med, 2021 06;18(3):377-385.
PMID: 34043210 DOI: 10.1007/s13770-021-00343-2

BACKGROUND: Managing massive bone defects, a great challenge to orthopaedics reconstructive surgery. The problem arise is the supply of suitable bone is limited with many complications. Tissue-engineered hydroxyapatite bone (TEHB) scaffold impregnated with osteoprogenitor cells developed as an alternative to promote bone regeneration.
METHODS: This animal protocol has been approved by Universiti Kebangsaan Malaysia Animal Ethical Committee. The TEHB scaffold prepared from hydroxyapatite using gel casting method. A total of six adolescent female sheep were chosen for this study. Later, all the sheep were euthanized in a proper manner and the bone harvested for biomechanical study. Bone marrow was collected from iliac crest of the sheep and bone marrow stem cells (BMSCs) isolated and cultured. BMSCs then cultured in osteogenic medium for osteoprogenitor cells development and the plasma collected was seeded with osteoprogenitor cells mixed with calcium chloride. Bone defect of 3 cm length of tibia bone created from each sheep leg and implanted with autologous and TEHB scaffold in 2 different groups of sheep. Wound site was monitored weekly until the wound completely healed and conventional X-ray performed at week 1 and 24. Shear test was conducted to determine the shear force on the autologous bone and TEHB scaffold after implantation for 24 weeks.
RESULTS: All of the sheep survived without any complications during the study period and radiograph showed new bone formation. Later, the bone harvested was for biomechanical study. The highest shear force for the autologous group was 13 MPa and the lowest was 5 MPa while for the scaffold group, the highest was 10 MPa and the lowest was 3 MPa. Although, proximal and distal interface of autologous bone graft shows higher shear strength compared to the TEHB scaffold but there is no significant difference in both groups, p value > 0.05. Histologically in both proximal and distal interface in both arms shows bone healing and woven bone formation.
CONCLUSION: TEHB scaffold impregnated with osteoprogenitor cells has the potential to be developed as a bone substitute in view of its strength and capability to promote bone regeneration.

Matched MeSH terms: Bone Regeneration
Fulltext IN VITRO SHOOT PROLIFERATION OF Begonia pavonina: A COMPARISON OF SEMISOLID, LIQUID, AND TEMPORARY IMMERSION MEDIUM SYSTEM

Rosilah Ab Aziz, Kodi Isparan Kandasamy, Faridah Qamaruz Zaman, Parameswari Namasivayam

Journal of Academia Universiti Teknologi MARA Negeri Sembilan, 2021;9(1):39-48.
MyJurnal

The in vitro shoot proliferation of endemic Begonia pavonina in three culture conditions i.e semisolid medium (SM), liquid culture medium (LM) and in temporary immersion bioreactor system (RITA®) was analyzed in this study. To minimize contamination rates, seeds were surface sterilized and cultured on MS basal media. The clean raised shoots were then used as explants for inoculation onto the tested culture conditions. In this experiment, the explants were maintained in MS medium supplemented with 0.1mgL-1 BAP for shoot multiplication. After 4 weeks of incubation, higher regeneration rates were observed in TIM as compared to other medium conditions. The maximum shoot number was obtained from TIM system with a mean of 5.30 shoots per explant, followed by LM (2.47 shoots per explant) and SM (1.2 shoots per explant). Shoot hyperhydration was also lowest in a TIM system. Overall, TIM was shown to produce higher shoot multiplications combined with healthy morphological characteristics of plantlets. Shoot cultures from the all cultures were successfully rooted in vitro and acclimatized well in the greenhouse.

Matched MeSH terms: Regeneration
Therapeutic potential of culinary-medicinal mushrooms for the management of neurodegenerative diseases: diversity, metabolite, and mechanism

Phan CW, David P, Naidu M, Wong KH, Sabaratnam V

Crit Rev Biotechnol, 2015;35(3):355-68.
PMID: 24654802 DOI: 10.3109/07388551.2014.887649

Mushrooms have long been used not only as food but also for the treatment of various ailments. Although at its infancy, accumulated evidence suggested that culinary-medicinal mushrooms may play an important role in the prevention of many age-associated neurological dysfunctions, including Alzheimer's and Parkinson's diseases. Therefore, efforts have been devoted to a search for more mushroom species that may improve memory and cognition functions. Such mushrooms include Hericium erinaceus, Ganoderma lucidum, Sarcodon spp., Antrodia camphorata, Pleurotus giganteus, Lignosus rhinocerotis, Grifola frondosa, and many more. Here, we review over 20 different brain-improving culinary-medicinal mushrooms and at least 80 different bioactive secondary metabolites isolated from them. The mushrooms (either extracts from basidiocarps/mycelia or isolated compounds) reduced beta amyloid-induced neurotoxicity and had anti-acetylcholinesterase, neurite outgrowth stimulation, nerve growth factor (NGF) synthesis, neuroprotective, antioxidant, and anti-(neuro)inflammatory effects. The in vitro and in vivo studies on the molecular mechanisms responsible for the bioactive effects of mushrooms are also discussed. Mushrooms can be considered as useful therapeutic agents in the management and/or treatment of neurodegeneration diseases. However, this review focuses on in vitro evidence and clinical trials with humans are needed.

Matched MeSH terms: Nerve Regeneration
Autologous implantation of bilayered tissue-engineered respiratory epithelium for tracheal mucosal regenesis in a sheep model

Mohd Heikal MY, Aminuddin BS, Jeevanan J, Chen HC, Sharifah SH, Ruszymah BH

Cells Tissues Organs, 2010;192(5):292-302.
PMID: 20616535 DOI: 10.1159/000318675

The objective of this study was to regenerate the tracheal epithelium using autologous nasal respiratory epithelial cells in a sheep model. Respiratory epithelium and fibroblast cells were harvested from nasal turbinates and cultured for 1 week. After confluence, respiratory epithelium and fibroblast cells were suspended in autologous fibrin polymerized separately to form a tissue-engineered respiratory epithelial construct (TEREC). A 3 × 2 cm² tracheal mucosal defect was created, and implanted with TEREC and titanium mesh as a temporary scaffold. The control groups were divided into 2 groups: polymerized autologous fibrin devoid of cells (group 1), and no construct implanted (group 2). All sheep were euthanized at 4 weeks of implantation. Gross observation of the trachea showed minimal luminal stenosis formation in the experimental group compared to the control groups. Macroscopic evaluation revealed significant mucosal fibrosis in control group 1 (71.8%) as compared to the experimental group (7%). Hematoxylin and eosin staining revealed the presence of minimal overgrowth of fibrous connective tissue covered by respiratory epithelium. A positive red fluorescence staining of PKH26 on engineered tissue 4 weeks after implantation confirmed the presence of cultured nasal respiratory epithelial cells intercalated with native tracheal epithelial cells. Scanning electron microscopy showed the presence of short microvilli representing immature cilia on the surface of the epithelium. Our study showed that TEREC was a good replacement for a tracheal mucosal defect and was able to promote natural regenesis of the tracheal epithelium with minimal fibrosis. This study highlighted a new technique in the treatment of tracheal stenosis.

Matched MeSH terms: Regeneration*; Guided Tissue Regeneration/methods*
Fulltext Evaluation of the osteogenic potential of demineralized and decellularized bovine bone granules following implantation in rat calvaria critical-size defect model

Al Qabbani A, Rani KGA, AlKawas S, Sheikh Abdul Hamid S, Yap Abdullah A, Samsudin AR, et al.

PLoS One, 2023;18(12):e0294291.
PMID: 38127838 DOI: 10.1371/journal.pone.0294291

The aim of this study was to compare the ability of demineralized (DMB) and decellularized (DCC) bovine bone granules to support bone regeneration in rat calvaria critical-size defects. DMB and DCC were prepared using a previously published method. The granule size used ranged between 500 and 750 μm. A total of forty-eight Sprague-Dawley rats were divided into two groups (n = 24). A pair of 5 mm diameter defects were created on the calvaria of the rats in the right and left parietal bone in both groups. Group A animals received DMB granules and Group B received DCC granules in the right parietal defect side while the left parietal untreated defect acted as sham surgery for both groups. Four animals per group were euthanized in a CO2 chamber at day 7, 14 and 21 post-surgery and the calvaria implantation site biopsy harvested was subjected to osteogenic gene expression analysis. Another four animals per group were euthanized at days 15, 30 and 60 post surgery and the calvaria implantation site biopsy harvested was subjected to histological, immunohistochemistry, RAMAN spectroscopy and Micro-CT analysis at the mentioned time points. Statistical analysis was conducted using t-tests and ANOVA. Histomorphometry showed significantly higher new bone formation in the DCC sites (p<0.05) compared to DMB. Both DMB and DCC implantation sites showed distinct staining for osteocalcin and osteopontin proteins compared to their respective sham sites. By day 21 after implantation, DCC sites demonstrated significantly elevated mRNA levels of osteonectin (p<0.001), osteopontin (p<0.001), osteocalcin (p<0.0001), ALP (p<0.01), and BMP-2 (p<0.001) compared to DMB. However, VEGF expression showed no significant differences at this time point between the two groups. Micro-CT analysis also showed enhanced defect closure and higher bone density in DCC implanted sites while RAMAN spectra demonstrated increased abundance of collagen and bone minerals, especially, PO43- ions than DMB. In conclusion, both DMB and DCC granules demonstrated favorable osteogenic potential in critical-sized defects, with DCC exhibited superior osteoconductive, osteoinductive and osteogenesis properties.

Matched MeSH terms: Bone Regeneration
Electrospun PAN/PEG Nanofibrous Membrane Embedded with a MgO/gC3N4 Nanocomposite for Effective Bone Regeneration

Danagody B, Bose N, Rajappan K, Iqbal A, Ramanujam GM, Anilkumar AK

ACS Biomater Sci Eng, 2024 Jan 08;10(1):468-481.
PMID: 38078836 DOI: 10.1021/acsbiomaterials.3c00892

Developing biomaterial scaffolds using tissue engineering with physical and chemical surface modification processes can improve the bioactivity and biocompatibility of the materials. The appropriate substrate and site for cell attachment are crucial in cell behavior and biological activities. Therefore, the study aims to develop a conventional electrospun nanofibrous biomaterial using reproducible surface topography, which offers beneficial effects on the cell activities of bone cells. The bioactive MgO/gC3N4 was incorporated on PAN/PEG and fabricated into a nanofibrous membrane using electrospinning. The nanocomposite uniformly distributed on the PAN/PEG nanofiber helps to increase the number of induced pores and reduce the hydrophobicity of PAN. The physiochemical characterization of prepared nanoparticles and nanofibers was carried out using FTIR, X-ray diffraction (XRD), thermogravimetry analysis (TGA), X-ray photoelectron spectroscopy (XPS), and water contact angle measurements. SEM and TEM analyses examined the nanofibrous morphology and the structure of MgO/gC3N4. In vitro studies such as on ALP activity demonstrated the membrane's ability to regenerate new bone and healing capacity. Furthermore, alizarin red staining showed the increasing ability of the cell-cell interaction and calcium content for tissue regeneration. The cytotoxicity of the prepared membrane was about 97.09% of live THP-1 cells on the surface of the MgO/gC3N4@PAN/PEG membrane evaluated using MTT dye staining. The soil burial degradation analysis exhibited that the maximum degradation occurs on the 45th day because of microbial activity. In vitro PBS degradation was observed on the 15th day after the bulk hydrolysis mechanism. Hence, on the basis of the study outcomes, we affirm that the MgO/gC3N4@PAN/PEG nanofibrous membrane can act as a potential bone regenerative substrate.

Matched MeSH terms: Bone Regeneration
Efficacy and bone-contact biocompatibility of glass ionomer cement as a biomaterial for bone regeneration: A systematic review

Tuygunov N, Zakaria MN, Yahya NA, Abdul Aziz A, Cahyanto A

J Mech Behav Biomed Mater, 2023 Oct;146:106099.
PMID: 37660446 DOI: 10.1016/j.jmbbm.2023.106099

Bone regeneration is a rapidly growing field that seeks to develop new biomaterials to regenerate bone defects. Conventional bone graft materials have limitations, such as limited availability, complication, and rejection. Glass ionomer cement (GIC) is a biomaterial with the potential for bone regeneration due to its bone-contact biocompatibility, ease of use, and cost-effectiveness. GIC is a two-component material that adheres to the bone and releases ions that promote bone growth and mineralization. A systematic literature search was conducted using PubMed-MEDLINE, Scopus, and Web of Science databases and registered in the PROSPERO database to determine the evidence regarding the efficacy and bone-contact biocompatibility of GIC as bone cement. Out of 3715 initial results, thirteen studies were included in the qualitative synthesis. Two tools were employed in evaluating the Risk of Bias (RoB): the QUIN tool for assessing in vitro studies and SYRCLE for in vivo. The results indicate that GIC has demonstrated the ability to adhere to bone and promote bone growth. Establishing a chemical bond occurs at the interface between the GIC and the mineral phase of bone. This interaction allows the GIC to exhibit osteoconductive properties and promote the growth of bone tissue. GIC's bone-contact biocompatibility, ease of preparation, and cost-effectiveness make it a promising alternative to conventional bone grafts. However, further research is required to fully evaluate the potential application of GIC in bone regeneration. The findings hold implications for advancing material development in identifying the optimal composition and fabrication of GIC as a bone repair material.

Matched MeSH terms: Bone Regeneration

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