Standardization of sterilization time and plant bioregulators for callus formation in hybrid Lilium cv. Fangio

Several growth hormone combinations and silver nitrate concentrations were examined for their effect on regeneration of different pepper genotypes. Primary leaf explants from in vitro seedlings were cultured on a revised Murashige and Skoog medium supplemented with auxin, cytokinin and 1.6% glucose. Combinations of different concentrations of indole-3-acetic acid (IAA), 0-5 mg/l, and 6-benzylaminopurine (BAP), 0-5 mg/l, were tested to determine the most effective medium for shoot primordium formation. Experiments with IAA and BAP did not result in a specific growth hormone combination appropriate for regeneration of all genotypes tested. Of the silver nitrate concentrations tested, 10 mg/l resulted in the best shoot and leaf differentiation and reduced callus formation. Differences in organogenic response of individual genotypes were evaluated on a single regeneration medium. Whole plants were regenerated from 11 of 63 genotypes examined. Based on these experiments, a reproducible regeneration system for pepper was developed with a total of 500 plants regenerated to date.

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Utilization of Different Seedling Explants for in Vitro Propagation of Hibiscus syriacus

HortScience ◽

10.21273/hortsci.33.3.478e ◽

1998 ◽

Vol 33 (3) ◽

pp. 478e-479

Author(s):

M.M. Jenderek ◽

A.J. Olney

Keyword(s):

Callus Formation ◽

Adventitious Bud ◽

Root Explants ◽

Petiole Explants ◽

Bud Formation ◽

Hypocotyl Explants ◽

Leaf Petiole ◽

Adventitious Bud Formation ◽

Hibiscus Syriacus

Hibiscus syriacus is a difficult species in micropropagation due to its endogenous contamination and recalcitrant shoot formation; therefore, studies on using explants other than shoot tip or axillary buds of growing shrubs were initiated. Three different seedling fragments (root, hypocotyl, and leaf petiole) from aseptically germinated seedlings of hibiscus (var. Aphrodite) were evaluated for adventitious bud formation, shoot and leaf development. The explants were cultured on McCown's woody plant basal salt medium supplemented with KNO3 (800 mg/L), adenine sulfate (80 mg/L) and MS vitamins containing BA or 2iP or TDZ at 0.5, 1.0, 2.2, 4.4 and 10 mM. Adventitious buds were present on all of the three different explants grown on medium containing TDZ; however, the most abundant bud formation, with many small leaves originating from callus was observed on hypocotyl explants cultured on medium with 1 mM of TDZ. Petiole explants were the most frequent to develop short shoots (≈15 mm) and one to nine leaves without callus formation, where 70% of hypocotyl and the root explants formed leaves originating from callus. Callus was induced on all explant types regardless of the level or type of cytokinin used. However, the number of shoots produced by any explant type was low, petioles cultured on 0.5 and 1mM of TDZ were the most suitable material for non-callus shoot development in H. syriacus. Hypocotyl explants proved to be an excellent source for adventitious bud formation but their ability to develop shoots needs to be investigated.

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Comparative transcriptome analysis reveals molecular regulators underlying pluripotent cell induction and callus formation in Anthurium andraeanum “Alabama”

In Vitro Cellular & Developmental Biology - Plant ◽

10.1007/s11627-020-10138-0 ◽

2021 ◽

Author(s):

Shuigen Li ◽

Jikai Li ◽

Xiufen Li ◽

Yuan Guan ◽

Minmin Chen ◽

...

Keyword(s):

Transcriptome Analysis ◽

Callus Formation ◽

Comparative Transcriptome ◽

Pluripotent Cell ◽

Comparative Transcriptome Analysis ◽

Cell Induction ◽

Anthurium Andraeanum

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Validating scoring systems for fracture healing in infants and young children: pilot study

Pediatric Radiology ◽

10.1007/s00247-021-05038-3 ◽

2021 ◽

Author(s):

Samuel Crompton ◽

Fabrizio Messina ◽

Gillian Klafkowski ◽

Christine Hall ◽

Amaka C. Offiah

Keyword(s):

Pilot Study ◽

Young Children ◽

Fracture Healing ◽

Callus Formation ◽

Femoral Fractures ◽

Scoring Systems ◽

Power Calculation ◽

Small Pilot Study ◽

Fractures In Children ◽

Infants And Young Children

Abstract Background Recent studies have analysed birth-related clavicular fractures to propose time frames for healing that could be applied to dating of all fractures in cases of suspected child abuse. Objective To assess differences in healing rates between femoral fractures and birth-related clavicular fractures in infants and young children. Materials and methods A retrospective 5-year pilot study of femoral fractures in children younger than 3 years of age was performed. Anonymised radiographs were independently scored by two radiologists for stages of fracture healing. In cases of reader disagreement, radiographs were independently scored by a third radiologist. Results In total, 74 radiographs (30 children) met the inclusion criteria. Fracture healing evolved over time with subperiosteal new bone formation (SPNBF) appearing first, followed by callus then remodelling. A power calculation for a single proportion, with a level of confidence of 95% and a margin of error of 5%, showed that in a definitive study, 359 radiographs would be required. Conclusion Although the overall pattern of healing is similar, in this small pilot study, the earliest times for SPNBF and callus formation in femoral fractures appeared to lag behind healing of birth-related clavicular fractures. Remodelling appeared earlier than remodelling of clavicular fractures. A power calculation has determined numbers of femoral radiographs (359) required for a definitive study.

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Callus Formation by Electret

Japanese Journal of Applied Physics ◽

10.1143/jjap.14.2079 ◽

1975 ◽

Vol 14 (12) ◽

pp. 2079-2080 ◽

Cited By ~ 28

Author(s):

Eiichi Fukada ◽

Toshiaki Takamatsu ◽

Iwao Yasuda

Keyword(s):

Callus Formation

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Can Optimizing the Mechanical Environment Deliver a Clinically Significant Reduction in Fracture Healing Time?

Biomedicines ◽

10.3390/biomedicines9060691 ◽

2021 ◽

Vol 9 (6) ◽

pp. 691

Author(s):

Jan Barcik ◽

Devakara R. Epari

Keyword(s):

Fracture Healing ◽

Bone Healing ◽

Mechanical Stimulation ◽

Callus Formation ◽

Weight Bearing ◽

Healing Process ◽

Healing Time ◽

Mechanical Environment ◽

Clinically Significant ◽

The Impact

The impact of the local mechanical environment in the fracture gap on the bone healing process has been extensively investigated. Whilst it is widely accepted that mechanical stimulation is integral to callus formation and secondary bone healing, treatment strategies that aim to harness that potential are rare. In fact, the current clinical practice with an initially partial or non-weight-bearing approach appears to contradict the findings from animal experiments that early mechanical stimulation is critical. Therefore, we posed the question as to whether optimizing the mechanical environment over the course of healing can deliver a clinically significant reduction in fracture healing time. In reviewing the evidence from pre-clinical studies that investigate the influence of mechanics on bone healing, we formulate a hypothesis for the stimulation protocol which has the potential to shorten healing time. The protocol involves confining stimulation predominantly to the proliferative phase of healing and including adequate rest periods between applications of stimulation.

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Internal Radioulnar Fixation for Treatment of Nonunion of Proximal Radius and Ulna Fractures in a Toy Breed Dog

VCOT Open ◽

10.1055/s-0041-1723831 ◽

2021 ◽

Vol 04 (01) ◽

pp. e24-e31

Author(s):

Luca Vezzoni ◽

Paolo Abrescia ◽

Aldo Vezzoni

Keyword(s):

Locking Plate ◽

Callus Formation ◽

Previous Treatment ◽

Bone Morphogenetic Protein 2 ◽

Distal Ulna ◽

Proximal Ulna ◽

Proximal Radius ◽

Locking Screws ◽

Morphogenetic Protein ◽

Ulna Fractures

AbstractIn this case report, we describe an alternative surgical procedure to treat proximal radius and ulnar nonunion in a toy breed dog. A 14-month-old, Maltese cross-breed dog was referred after previous treatment with external and internal fixation had failed, resulting in a nonunion of a fracture of the proximal radius and ulna with the proximal radius fragment too small and friable to be used for fixation. A craniomedial approach was made to debride the radius nonunion site and a second approach to the lateral aspect of the ulna was made. The fracture was realigned and a titanium locking plate was applied in bridging fashion, fixed to the proximal ulnar fragment with three locking screws in the most proximal plate holes, a fourth screw was inserted in the mid-shaft of the distal ulnar fragment and three locking screws were inserted in the distal most holes of the plate through the distal ulna to engage the distal radial fragment. A recombinant bone morphogenetic protein 2 graft was inserted into the radius and ulna fracture sites. The dog had a successful clinical and radiographic outcome with bridging of the defect 4 weeks postoperatively and complete callus formation 8 weeks postoperatively. Implants have undergone dynamization and then removal. Use of a locking plate as an internal fixator achieving fixation of the proximal ulna and distal radius can be considered an option for the treatment of proximal radioulnar nonunions with a small proximal radial fragment.

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Transcutaneous CO2 application accelerates fracture repair in streptozotocin-induced type I diabetic rats

BMJ Open Diabetes Research & Care ◽

10.1136/bmjdrc-2019-001129 ◽

2020 ◽

Vol 8 (2) ◽

pp. e001129

Author(s):

Takahiro Oda ◽

Takahiro Niikura ◽

Tomoaki Fukui ◽

Keisuke Oe ◽

Yu Kuroiwa ◽

...

Keyword(s):

Endochondral Ossification ◽

Callus Formation ◽

Femoral Shaft ◽

Shaft Fracture ◽

Diabetic Rats ◽

Fracture Repair ◽

Female Rats ◽

Control Group ◽

Type I ◽

Biomechanical Assessment

IntroductionDiabetes mellitus (DM) negatively affects fracture repair by inhibiting endochondral ossification, chondrogenesis, callus formation, and angiogenesis. We previously reported that transcutaneous CO2 application accelerates fracture repair by promoting endochondral ossification and angiogenesis. The present study aimed to determine whether CO2 treatment would promote fracture repair in cases with type I DM.Research design and methodsA closed femoral shaft fracture was induced in female rats with streptozotocin-induced type I DM. CO2 treatment was performed five times a week for the CO2 group. Sham treatment, where CO2 was replaced with air, was performed for the control group. Radiographic, histologic, genetic, and biomechanical measurements were taken at several time points.ResultsRadiographic assessment demonstrated that fracture repair was induced in the CO2 group. Histologically, accelerated endochondral ossification and capillary formation were observed in the CO2 group. Immunohistochemical assessment indicated that early postfracture proliferation of chondrocytes in callus was enhanced in the CO2 group. Genetic assessment results suggested that cartilage and bone formation, angiogenesis, and vasodilation were upregulated in the CO2 group. Biomechanical assessment revealed enhanced mechanical strength in the CO2 group.ConclusionsOur findings suggest that CO2 treatment accelerates fracture repair in type I DM rats. CO2 treatment could be an effective strategy for delayed fracture repair due to DM.

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