• Advances in biomechanics and applications
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• v.1 no.2
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• pp.95-109
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• 2014

Peri-acetabular bone ingrowth plays a crucial role in long-term stability of press-fit acetabular cups. A poor bone ingrowth often results in increased cup migration, leading to aseptic loosening of the implant. The rate of peri-prosthetic bone formation is also affected by the polar gap that may be introduced during implantation. Applying a mechano-regulatory tissue differentiation algorithm on a two-dimensional plane strain microscale model, representing implant-bone interface, the objectives of the study are to gain an insight into the process of peri-prosthetic tissue differentiation and to investigate its relationship with implant-bone relative displacement and size of the polar gap. Implant-bone relative displacement was found to have a considerable influence on bone healing and peri-acetabular bone ingrowth. An increase in implant-bone relative displacement from $20{\mu}m$ to $100{\mu}m$ resulted in an increase in fibrous tissue formation from 22% to 60% and reduction in bone formation from 70% to 38% within the polar gap. The increase in fibrous tissue formation and subsequent decrease in bone formation leads to weakening of the implant-bone interface strength. In comparison, the effect of polar gap on bone healing and peri-acetabular bone ingrowth was less pronounced. Polar gap up to 5 mm was found to be progressively filled with bone under favourable implant-bone relative displacements of $20{\mu}m$ along tangential and $20{\mu}m$ along normal directions. However, the average Young's modulus of the newly formed tissue layer reduced from 2200 MPa to 1200 MPa with an increase in polar gap from 0.5 mm to 5 mm, suggesting the formation of a low strength tissue for increased polar gap. Based on this study, it may be concluded that a polar gap less than 0.5 mm seems favourable for an increase in strength of the implant-bone interface.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.3
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• pp.291-309
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• 2000

Statement of problem. There were several studies on the effects of irradiation to peri-implant bone tissue. However, no clear biological effect of irradiation on peri-implant bone tissue was reported yet. Purpose. This study compared the effect of irradiation on the surrounding tissue of a HA-coated implant fixture with controls. Material and methods. 6 Steri-Oss implants were implanted into the femur of 6 mongrels. The implanted dogs were divided into three groups and received irradiation. After 1 month, 2months and 4 months healing period, the histologic examination and mobility test and digital radiographic imaging analyses were performed to compare the control and experimental group respectively. Results. The irradiated group showed slower healing than control group in light microscopic observations. The mobility test demonstrated significant less number (Periotest) in control group than that of irradiated groups. The digital radiographic imaging analysis showed that the bone density of irradiated group was higher than control group. Conclusion. Generally, control group showed favorable biological response and less mobility than irradiated group. The conflict result of bone density value were measured by the digital radiographic imaging analysis. The digital radiographic imaging analysis needs more research in future.

• Reproductive and Developmental Biology
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• v.38 no.1
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• pp.9-19
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• 2014

For successful embryo implantation, the communication of the maternal endometrium with the conceptus trophectoderm is required essentially. In pigs, conceptuses undergo morphological change in length to enlarge the physical contact area with the maternal endometrium and secrete estrogen to induce the maternal recognition of pregnancy during the peri-implantation period. Conceptus-derived estrogen prevents luteolysis by conversion in direction of $PGF_{2{\alpha}}$ secretion from the uterine vasculature to the uterine lumen as well as it affects on expression of the uterine endometrial genes. In addition to estrogen, conceptuses release various signaling molecules, including cytokines, growth factors, and proteases, and, in response to these signaling molecules, the maternal uterine endometrium also synthesizes many signaling molecules, including hormones, cytokines, growth factors, lipid molecules, and utilizes ions such as calcium ion by calcium regulatory molecules. These reciprocal interactions of the conceptus trophectoderm with the maternal uterine endometrium make development and successful implantation of embryos possible. Thus, signaling molecules at the maternal-conceptus interface may play an important role in the implantation process. This review summarized syntheses and functions of signaling molecules at the maternal-conceptus interface to further understand mechanisms of the embryo implantation process in pigs.

• Korean Journal of Veterinary Research
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• v.43 no.2
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• pp.289-294
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• 2003

This study aimed to determine of osseointegration following dental implantation in the dog mandible using bone scintigraphy. Five mongrel dogs, weighing approximately 8.5 kg and averaging 1.8 years of age, without active periodontal disease were used. During the entire study period, all dogs were fed a soft commercial diet and water ad libitum to minimize functional loading of the implant. Titanium alloy implant systems 10 mm in length and 4 mm in diameter were chosen for insertion. Twelve weeks prior to implantation, the second and third left mandibular premolars in each dog were extracted for the dental implant insertion. Before the dental implantation procedures and 0, 4, 8, and 12 weeks after the insertions, clinical observation, radiography and bone scintigraphy were conducted. The scintigraphy was obtained using a large field of view gamma camera equipped with a paralled-hole, low-energy collimator about 3 hours after intravenous injection of Tc-99m-MDP (8 mCi/dog) to the dogs. There were not inflammation sign after insertion of dental implants on the mandible in dogs. Implants were slightly movable at the first and fourth weeks, and there was no mobility after 8 weeks. Twelve weeks after dental implantation, the bone uptake scintigraphy of peri-implant bone was similar to that of normal alveolar bone, indicating that peri-implant bone was completely regenerated by new bone. In conclusion, we recommend stable implant fixation with alveolar bone for the accurate and safe repair of teeth loot due to decacy, trauma or peridontal disease. Titanium alloy implants were optimal due to their biocompatibility.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.6
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• pp.845-855
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• 2000

As high as 50% of pregnancies are known to fail and the majority of such losses occur during the peri-implantation period. For the establishment of pregnancy in mammalian species, therefore, implantation of the conceptus to the maternal endometrium must be completed successfully. Physiological events associated with implantation differ among mammals. In ruminant ungulates, an elongation of the trophohlast in early conceptus development is required before the attachment of the conceptus to the uterine endometrium. Moreover, implantation sites are restricted to each uterine caruncula where tissue remodeling, feto-maternal cell fusion and placentation take place in a coordinated manner. These unique events occur under strict conditions and are regulated by numerous factors from the uterine endometrium and trophoblast in a spatial manner. Interferon-tau (IFN-${\tau}$), a conceptus-derived anti-Iuteolytic factor, which rescues corpus luteum from its regression in ruminants, is particularly apt to play an important role as a local regulator in coordination with other factors, such as TGF-${\beta}$, Cox-2 and MMPs at the attachment and placentation sites.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.225-225
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• 2004

Acyl-CoA synthetase 4(ACS4) is an arachidonate-preferring enzyme aboundant in steroidogenic tissues and postulated to modulate eicosanoid production. Most of arachidonate present in cells is esterified predominantly in phospholipids. After its release by the action of calcium-dependent phospholipases, arachidonate can be converted to prostaglandins, thromboxanes, and leukotrenes via the cyclooxygenas and lipoxygenase pathways, respectively, depending on the cell type.(omitted)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05b
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• pp.22-25
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• 2001

A thyristor switch circuit for capacitor discharge application, of which the equivalent circuit includes a resistor between cathode and gate of a reverse-conducting thyristor and an avalanche diode anti-parallel between its anode and gate to set thyristor tum-on voltage, is monolithically integrated by planar process with AVE double-implantation method. To ensure a lower breakdown voltage of the avalanche diode for thyristor tum-on than the break-over voltage of the thyristor, $p^+$ wells on thyristor p base layer are made by boron implantation/drive-in for a steeper doping profile with higher concentrations while rest p layers of thyristor and free-wheeling diode parts are formed with Al implantation/drive-in for a doping profile of lower steepness. The free-wheeling diode part is isolated from the thyristor part by formation of separated p-well emitter for suppressing commutation between them, which is achieved during the formation of thyristor p-base layer.

• Journal of Yeungnam Medical Science
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• v.38 no.3
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• pp.175-182
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• 2021

Breast implant-associated anaplastic large-cell lymphoma (BIA-ALCL) is a rare T-cell non-Hodgkin lymphoma characterized as CD30 positive and anaplastic lymphoma kinase (ALK) negative. In 2016, the World Health Organization declared BIA-ALCL as a new disease entity. The first case of BIA-ALCL was reported in 1997, and as of July 2019, the United States Food and Drug Administration had cited a total of 573 United States and global medical device reports of BIA-ALCL, including 33 deaths. In all clinical case reports, except for those with unknown clinical history, the patient had received at least one textured surface breast implant. Although the etiology is not yet clear, chronic inflammation has been proposed as a potential precursor to tumorigenesis. The most common presentation of BIA-ALCL is peri-implant fluid collection following aesthetic or reconstructive implantation with textured surface breast implants. It can be accompanied by breast swelling, asymmetry, pain, skin lesions, lymphadenopathy, and B-type symptoms. Most cases are detected on average 7 to 10 years after implantation. Diagnostic specimens can be obtained with fine-needle aspiration or biopsy. BIA-ALCL is CD30 positive, epithelial membrane antigen positive, and ALK negative. It can be cured with complete surgical excision at the T1-T3 stage.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.6
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• pp.540-545
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• 2008

Since mid 20th century, dental treatments with laser have been introduced and improved a lot. Because early $CO_2$, Nd:YAG, diode, argon, and holmium lasers are used for dealing soft tissue, so it applied just limited field. But, in 1997 the lasers of erbium family that able to dealing soft and hard tissue also were introduced, laser application fields are enlarged. In today, the application fields reach on implantation treatment, so clinicians can use the laser to make holes for implantation, and flap elevation, even though treating peri-implantitis. So our class want to discover the optimal setting of Er:YAG laser when treating peri-implantitis. We observed the surface that initially treated by RBM and TPS passion and laser with varied options of exposure time and power with SEM image. For this we conclude the optimal setting range that does not alter the implant surface structure and report it.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.1
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• pp.38-48
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• 2019

Objective: In this study, the transcriptome profile of cow experiencing miscarriage during peri-implantation was investigated. Methods: Total transcriptomes were checked by RNA sequencing, and the analyzed by bioinformatics methods, the differentially expressed genes (DEGs) were analysed with hierarchical clustering and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis. Results: The results suggested that serum progesterone levels were significantly decreased in cows that miscarried as compared to the pregnant cows at 18, 21, 33, 39, and 51 days after artificial insemination. The RNA sequencing results suggested that 32, 176, 5, 10, and 2 DEGs were identified in the pregnant cows and miscarried cows at 18, 21, 33, 39, and 51 d after artificial insemination. And 15, 101, 1, 2, and 2 DEGs were upregulated, and 17, 74, 4, and 8 DEGs were downregulated in the cows in the pregnant and miscarriage groups, respectively at 18, 21, 33, and 39, but no gene was downregulated at 51 d after artificial insemination. These DEGs were distributed to 13, 20, 3, 6, and 20 pathways, and some pathway essential for pregnancy, such as cell adhesion molecules, tumor necrosis factor signaling pathway and PI3K-Akt signaling pathway. Conclusion: This analysis has identified several genes and related pathways crucial for pregnancy and miscarriage in cows, as well as these genes supply molecular markers to predict the miscarriage in cows.