Influence of melatonin on processes of the bone tissue physiological regeneration of young and adult rats

Bone tissue can detect and respond to its mechanical environment, but there is no consensus for how bone cells detect mechanical loads. Some think that cells sense tissue deformation (strain) and respond when strain is abnormally high. However, strains in bone tissue are usually very small, and it is questionable whether bone cells are sensitive enough to detect them. Another theory suggests that mechanical loads are coupled to the bone cells by stress-generated fluid flow within the bone tissue, which is dependent on the rate of change of bone strain. We applied bending loads to the tibiae of adult rats to create equivalent peak strains in the bone tissue but with varied rates of strain. Bone formation was significantly increased in the two experimental groups when the highest strain rates were compared with lower strain rates (P < 0.01), and the amount of new bone formation was directly proportional to the rate of strain in the bone tissue. These results suggest that relatively large strains alone are not sufficient to activate bone cells. High strain rates and possibly stress-generated fluid flow are required to stimulate new bone formation.

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Effectiveness of Russian current in bone regeneration process in rats

Fisioterapia em Movimento ◽

10.1590/1980-5918.030.002.ao13 ◽

2017 ◽

Vol 30 (2) ◽

pp. 329-336

Author(s):

Renata Aparecida de Oliveira Lima ◽

Ana Paula Coelho Figueira Freire ◽

Alcides Guimarães ◽

Caroline Pereira Santos ◽

Francis Lopes Pacagnelli

Keyword(s):

Bone Tissue ◽

Tissue Repair ◽

Low Cost ◽

Intervention Group ◽

Average Frequency ◽

Repair Process ◽

Control Group ◽

Stimulation Protocol ◽

Treatment Results ◽

Adult Rats

Abstract Introduction: Russian current is an electric current of average frequency that is able to restore the properties of skeletal muscle at a low treatment cost. It is essential to know the effects of Russian current in bone tissue, since electromagnetic energy could be an efficient and low cost method to treat bone disorders. Objective: The aim of the study was to evaluate the effectiveness of Russian current in the consolidation of tibia fracture in adult rats. Methods: 24 adult male Albinus Wistar rats wereused. The animals were divided randomly into two groups: control group (CG), composed of 12 animals, and Intervention Group (IG) consisting of 12 animals, both groups were submitted to osteotomy (proximal medial surface of the tibia). The IG underwent an electrical stimulation protocol with Russian current, while the CG did not undergo any kind of intervention. Euthanasia was performed in three animals of each group on the following days: 5, 10, 20, and 30 days of treatment. Results: The results suggested higher primary ossification, intense osteogenic activity, and increased thickness of the periosteum, characterizing more advanced ossification and a greater presence of trabecular bone marrow in rats in the group subjected to the treatment. In this way, we can assign one more beneficial effect to interventions with Russian current, for the treatment of postfracture rehabilitation. Conclusion: In both groups the bone tissue repair process occurred, but in the electrically stimulated group the osteogenesis process was more advanced.

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Strontium ranelate promotes increased peri-implant bone formation in ovariectomized rats.

Research Society and Development ◽

10.33448/rsd-v9i10.9092 ◽

2020 ◽

Vol 9 (10) ◽

pp. e7539109092

Author(s):

Fernanda Costa Yogui ◽

Ana Cláudia Ervolino-Silva ◽

Letícia Pitol-Palin ◽

Juliana Zorzi Coléte ◽

Jaqueline Suemi Hassumi ◽

...

Keyword(s):

Confocal Microscopy ◽

Bone Formation ◽

Bone Tissue ◽

Strontium Ranelate ◽

Statistical Tests ◽

Ovariectomized Rats ◽

Pcr Analysis ◽

Adult Rats ◽

Alizarin Red ◽

Reverse Torque

This study aimed to evaluate the systemic effect of strontium ranelate (SR) on peri-implant bone tissue. Thirty-six adult rats were divided into three experimental groups: sham (SHAM), ovariectomized (OVX) and ovariectomized rats treated with strontium ranelate (OVX-Sr). Strontium ranelate (625mg/kg) was administered by oral gavage on a daily basis. The implants were installed on the tibiae. The euthanasia occurred 42 and 60 days after the implants were installed, and the biomechanical (reverse torque); PCR-RT; histological; immunohistochemical; confocal microscopy and histometric analysis were performed. Quantitative data was subjected to statistical tests with significance level set at p<0.05. Significant increase in implant reverse torque in OVX-Sr was observed when compared to OVX. PCR analysis showed an increase in the genetic expression of the proteins responsible for bone formation in OVX-SR. In the histological analysis, SHAM and OVX-Sr showed a higher degree of maturation of peri-implant bone tissue. Ran-Sr presented higher immunolabeling for ALP and OPN proteins when compared to OVX. In the confocal microscopy, OVX-Sr there was good bone neoformation showed by incorporation of Alizarin red fluorochrome. The histometric analysis, bone implant contact (BIC) and neoformed bone area (NBA) presented statistically difference among all groups, and the Ran-Sr presented the highest BIC. Thus, strontium ranelate improves osseointegration and quality of neoformed bone tissue around implants in estrogen deficient rats.

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DIAGNOSTIC ULTRASOUND CHOOSEOPERA OF THE ALVEOLAR PROCESS, MANDIBLE AND MAXILLA

UZBEK MEDICAL JOURNAL ◽

10.26739/2181-0664-2020-5-4 ◽

2020 ◽

Vol 5 (1) ◽

pp. 28-33

Author(s):

Avzal Аkbarov ◽

◽

Jamshid Tulyaganov ◽

Nigora Ziyadullaeva

Keyword(s):

Bone Tissue ◽

Tissue Regeneration ◽

Diagnostic Ultrasound ◽

Complete Loss ◽

Bone Tissue Regeneration ◽

Alveolar Process ◽

Physiological Regeneration ◽

Dental Implantation ◽

Local Bone ◽

Bone Deficiency

Dental implantation is an established scientifically grounded method of treating patients with partial and complete loss of teeth. However, the dentist-implantologist often faces the problem of bone tissue regeneration after inflammatory, traumatic diseases and carrying out extraction interventions that lead to its deficiency. Physiological regeneration often does not provide the required volume of new bone. A local bone deficiency makes it difficult to carry out dental implantation

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Further Studies on the Ultrastructure of Harderian Gland in Adult Rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051451 ◽

1974 ◽

Vol 32 ◽

pp. 288-289

Author(s):

Alfredo Feria-Velasco ◽

Guadalupe Tapia-Arizmendi

Keyword(s):

Fine Structure ◽

Domestic Fowl ◽

Animal Species ◽

Acinar Cells ◽

Harderian Gland ◽

Myoepithelial Cells ◽

The Other ◽

Albino Rats ◽

Adult Rats ◽

Cell Components

The fine structure of the Harderian gland has been described in some animal species (hamster, rabbit, mouse, domestic fowl and albino rats). There are only two reports in the literature dealing on the ultrastructure of rat Harderian gland in adult animals. In one of them the author describes the myoepithelial cells in methacrylate-embbeded tissue, and the other deals with the maturation of the acinar cells and the formation of the secretory droplets. The aim of the present work is to analize the relationships among the acinar cell components and to describe the two types of cells located at the perifery of the acini.

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Biodegradable polyester neuroprostheses promote the reconnection of separated peripheral nerve stubs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130109 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1094-1095

Author(s):

Beverly L. Giammara ◽

Jennifer S. Stevenson ◽

Peggy E. Yates ◽

Robert H. Gunderson ◽

Jacob S. Hanker

Keyword(s):

Image Analysis ◽

Basement Membrane ◽

Periodic Acid ◽

Light And Electron Microscopy ◽

Computer Assisted ◽

Type Iii Collagen ◽

Image Analysis System ◽

Biodegradable Polyester ◽

Adult Rats ◽

Type Iv

An 11mm length of sciatic nerve was removed from 10 anesthetized adult rats and replaced by a biodegradable polyester Vicryl™ mesh sleeve which was then injected with the basement membrane gel, Matrigel™. It was noted that leg sensation and movement were much improved after 30 to 45 days and upon sacrifice nerve reconnection was noted in all animals. Epoxy sections of the repaired nerves were compared with those of the excised segments by the use of a variation of the PAS reaction, the PATS reaction, developed in our laboratories for light and electron microscopy. This microwave-accelerated technique employs periodic acid, thiocarbohydrazide and silver methenamine. It stains basement membrane or Type IV collagen brown and type III collagen (reticulin), axons, Schwann cells, endoneurium and perineurium black. Epoxy sections of repaired and excised nerves were also compared by toluidine blue (tb) staining. Comparison of the sections of control and repaired nerves was done by computer-assisted microscopic image analysis using an Olympus CUE-2 Image Analysis System.

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High-voltage EM description of the types and distribution of sensory endings in the inner conical body of the rat vibrissal follicle-sinus complex

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015959x ◽

1990 ◽

Vol 48 (3) ◽

pp. 410-411

Author(s):

Tony M. Mosconi ◽

Min J. Song ◽

Frank L. Rice

Keyword(s):

Mammalian Species ◽

Dorsal Side ◽

Hair Shaft ◽

Sensory Innervation ◽

Conical Body ◽

Adult Rats ◽

Perpendicular Plane ◽

Ultrastructural Studies ◽

Unmyelinated Axons ◽

Sensory Endings

Whiskers or vibrissal follicle-sinus complexes (F-SCs) on the snouts of many mammalian species are structures that have complex, dense sensory innervation. The innervation of F-SCs is remarkably similar in all species with the exception of one site - the inner conical body (ICB). The ICB is an elongated cylindrical structure that encircles the hair shaft near the neck of the follicle. This site has received only cursory attention in ultrastructural studies of the F-SCAdult rats were perfused after the method of Renehan and Munger2. F-SCs were quartered longitudinally and embedded separately in Epon-Araldite. Serial 0.25 μm sections were cut in either the longitudinal or perpendicular plane through the ICB and examined with an AEI EM7 1.2 MV HVEM (Albany, NY) at 1000 KV. Sensory endings were reconstructed from serial micrographs through at least 20 μm in the longitudinal plane and through 10 μm in the perpendicular plane.From two to six small superficial vibrissal nerves converge upon the neck of the F-SC and descend into the ICB. The nerves branch into smaller bundles of myelinated and unmyelinated axons along the dorsal side of the hair shaft.

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