• Journal of Chest Surgery
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• v.23 no.3
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• pp.438-451
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• 1990

Pneumatic total artificial heart[TAH] has been clinically applied for the purpose of permanent or temporary use followed by cardiac transplantation in the patients with end stage heart diseases. In spite of the good durability of the pneumatic TAH, thrombus formation, bleeding and infection resulted in death. The Tomasu heart, which is a type of pneumatic TAH, was used in this study. This model is a modified Jarvik heart and consists of atrial cuffs, outflow vascular grafts and thin-layer seamless diaphragm type of ventricles. Cardiac outputs of the left artificial heart were measured by Donovan`s mock circulation under variable conditions of driving parameters, and an experimental artificial heart implantation was performed in 4 calves to observe the changes of hemodynamic parameters in early postoperative period and hematologic and bio-chemical changes in a long-term survival case. In the mock circulation test, cardiac output of the heart was increased with the increase of the left atrial pressure and left driving pressure. Maximum cardiac output was obtained at the heart rate of 120 to 130/min and percent systole of 40 to 45Zo under the condition of a constant left driving pressure of 180mmHg and left atrial pressure of 10mmHg. During the first 24 hours of TAH pumping, driving pressure ranged from 178$\pm$5mmHg to 187$\pm$8mmHg for the left heart and from 58$\pm$6mmHg to 78$\pm$28mmHg for the right heart. The Mean arterial pressure significantly increased between 2 and 8 hours after the start of pumping. The survival time ranged from 27 hours to 46 days. The causes of death were respiratory failure in 2 cases, mechanical valve failure in one, and left ventricular outflow obstruction due to thrombus in a 46-day survival case. This study demonstrated that Tomasu artificial heart operated effectively during the first 24 hours of artificial heart pumping, but thrombus formation around the valve holding area was the main problem in long-term survival case.

• Journal of dental hygiene science
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• v.22 no.4
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• pp.249-255
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• 2022

Background: Sexual dimorphism is important for sex determination in the field of forensics. However, sexual dimorphism is commonly assessed using cone beam computed tomography (CBCT) rather than three-dimensional (3D) modeling software; therefore, studies using a more accurate measurement approach are necessary. This study assessed the sexual dimorphism of the MS using a 3D modeling program to obtain information that could contribute to the fields of surgery and forensics. Methods: The CBCT data of 60 patients (age, 20~29 y; 30 males and 30 females) admitted to the Department of Orthodontics at the Dankook University School of Dentistry were provided in Digital Imaging and Communications in Medicine (DICOM) format. The left MS and right MS were modeled based on the DICOM files using the Mimics (version 22; Materialise, Leuven, Belgium) 3D program and converted to stereolithography (STL) files used to measure the width, length, and height of the MS, infraorbital foramen (IOF), right MS, and left MS. The average of three repeated measurements was calculated, and a reliability test was performed to ensure data reliability (Cronbach's α=0.618). A canonical discriminant analysis was performed using a standard approach (left: Box's M=0.096; right: Box's M=0.115). Results: Males had greater values for all parameters (MS width, MS length, MS height, IOF, right MS, left MS) than females. The discriminant analysis identified six independent variables (MS width, MS height, MS length, IOF, right MS, left MS) that could identify sex. The left MS and right MS correctly identified the sex of 81.7% and 71.7% of the patients, respectively, with the left MS having higher accuracy. Conclusion: This study confirmed that, for Korean individuals, the left MS has a better ability to identify sex than the right MS. These results may contribute to sex identification in the fields of surgery and forensics.

• Korean Journal of Poultry Science
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• v.34 no.4
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• pp.253-257
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• 2007

Fayoumi chicks were vaccinated with fowl pox virus vaccine and pigeon pox virus vaccine. The protective potentiality of the two vaccines was compared in field condition in Bangladesh. The percentage of 'take reaction' was assessed to conclude its relationship with better immune response and recorded 93.33% and 100% in birds of group B and group C, respectively. The mean passive hemagglutination (PHA) antibody titre after primary vaccination was $32{\pm}14.81$ in group B and $33{\pm}13.66$ in group C. Following booster vaccination, the mean PHA titres level at pre challenge of group B was $46.93{\pm}16.52\;and\;55.46{\pm}14.64$ in group C. The PHA titre of group B and C at two weeks post challenge recorded $93.86{\pm}33.04\;and\;110.93{\pm}29.29$, respectively. PHA titre significantly (P<0.01) increased after vaccination and post challenge compared to pre- vaccination titre. There was significant variation (p<0.01) of PHA titre at pre challenge in these groups using different vaccine combinations, but all the vaccinated birds resisted challenge infection.

• Parasites, Hosts and Diseases
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• v.56 no.1
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• pp.53-59
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• 2018

Tick saliva is critically important for continuous attachment to the host, blood feeding for days, and transmission of tick-borne pathogens. To characterize the patterns of inflammatory cytokine gene expression during its attachment and blood sucking time, peripheral blood samples of rabbits infested with Haemaphysalis longicornis ticks were collected at different intervals. Blood histamine concentration was evaluated as well as gene encoding IFN-${\gamma}$, TNF-${\alpha}$, IL-2, IL-6, IL-4, and IL-10 were compared with non-infested rabbits. Blood histamine concentration of tick-infested rabbits during fast feeding time was significantly higher than that of non-infested rabbits. In both nymph and adult tick infested rabbits, expression of TNF-${\alpha}$ and IFN-${\gamma}$ genes were decreased significantly (P<0.05), while expression of IL-4, IL-6, and IL-10 were increased 1.3 to 7 folds in adult infested rabbits with the exception of IL-6 that was significantly (P<0.05) decreased in nymph infested rabbits. IL-2 was not expressed in either nymph or adult infestation. H. longicornis saliva is capable of modulate host responses through a complex correlation with histamine and Th1, Th2 mediated cytokines that suppress the inflammatory responses directed toward inflammatory mediators introduced into the host during tick feeding.

• Korean Journal of Materials Research
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• v.21 no.2
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• pp.125-132
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• 2011

Fibrous chitosan membranes were fabricated as a substrate for skin applications using an electro-spinning process with different solvents and varying concentrations. Scanning electron microscopy (SEM) images confirmed that the formation of the chitosan fibrous membrane in trifluoroacetic acid was better than that in acetic acid. Fourier transform infrared spectroscopy showed that the chitosan fibers were cross-linked with glutaraldehyde, and that the cytotoxicity of the aldehyde groups was reduced by glycine and washing by NaOH and DI water. Chitosan cross-linked fibrous membranes were insoluble in water and could be washed thoroughly to wash away glycine and excess NaOH and prevent the infiltration of other water soluble bio-toxic agents using DI water. MTT assay method was employed to test the cytotoxicity of chitosan membranes during fabricating, treating and washing processes. After the dehydration of cell cultured chitosan membranes, cell attachment behavior on the material was evaluated using SEM method. Effect of the treatment processes on the biocompatibility of the chitosan membranes was shown by comparing of filopodium and lamellipodium of fibroblast cells on grown washed and unwashed chitosan fibrous membrane. The MTT assay and SEM morphology confirmed that the washed chitosan fibrous membrane increased cell attachment and cell growth, and decreased toxicity compared to results for the unwashed chitosan fibrous membrane.

• Toxicological Research
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• v.22 no.3
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• pp.253-266
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• 2006

Bone is a dynamic tissue that is constantly being remodelled. Resolution of bone and formation of new bone are closely linked, so that bone mass remains constant. With age, this process becomes unlinked with an imbalance in bore resorption and formation that results in a net loss of bone. Especially, osteoporosis is a disease characterized by low bone mass with age. One form of aging-related primary osteoporosis is postulated with the reduction of circulating estrogen, rapid bone loss occurs as a result of enhanced bore remodelling with an excess of resorption over bore formation. The oxidative stress is also involved in the pathogenesis of osteoporosis. Oxidative stress by cytokines, such as IL-a and TNF-${\alpha}$, inhibits osteoblast function in vitro and stimulates osteoblast apoptosis resulting in an imbalance in bore remodelling. The present article reviews the current perspectives on the interaction between bone remodelling and factors such as estrogen and oxidative stress, providing an interpretation of bone diseases in a view of molecular mechanisms.

• Smart Structures and Systems
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• v.8 no.1
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• pp.1-15
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• 2011

Cerebral aneurysm is common lesion among adult population. Current methods for treating the disease have several limitations. Inspired by fern leaves, we have developed a new stent, called leaf stent, which can provide a tailored coverage at the neck of an aneurysm and thus prevent the blood from entering the aneurysm. It alone can be used to treat the cerebral aneurysm and therefore overcomes problems existing in current treating methods. The paper focuses on the numerical simulation of the leaf stents. The mechanical behaviour of the stent in various designs has been investigated using the finite element method. It has been found that certain designs provide adequate radial force and have excellent longitudinal flexibility. The performance of certain leaf stents is comparable and even superior to those of the commercially available cerebral stents such as the Neuroform stent and the Enterprise stent, commonly used for stent assisted coiling, while at the same time, providing sufficient coverage to isolate the aneurysm without using coils.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.8
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• pp.984-991
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• 2011

The aim of this study is to develop a humeral Intramedullary fixation nail (HIFN) suitable for Korean people. In this study, CT images were obtained from 72 Korean cadaveric humeral bones and 3D Korean humeral bone models were reconstructed based on the CT images to investigate anatomical characteristics. Major design parameters of HIFN were selected using the morphological measurement information of the Korean humeral bone models. Through finite element analysis and mechanical tests, the developed HIFN prototype was compared with the Polarus HIFN ($ACUMED^{(R)}$, USA), and it was found that the HIFN prototype showed similar and/or superior mechanical performance compared to the Polarus HIFN. Also, clinical validation for the HIFN prototype was carried out to check predictable troubles in surgical operations. Finally, optimal design modification was proposed to prevent the possible axillary nerve injury due to the locking screw system of the HIFN prototype.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.203-204
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• 2006

Studies on some biodegradable polymers and other materials such as hydrogels have shown the promising potential for a variety of surgical applications. Postoperative adhesion caused by the natural consequence of surgical wound healing results in problems of the repeated surgery. Recently, scientists have developed absorbable anti-adhesion barriers that can protect a tissue from adhesion in case they are in use; however, they are dissolved when no longer needed. Although these approaches have been attempted to fulfill the criteria for adhesion prevention, none can perfectly prevent adhesions in all situations. Overall of this work, a new method to fabricate an anti-adhesion membrane using biodegradable polymer and hydrogel has been developed. The ideal barrier for preventing postoperative adhesion would have the following properties; it should be (i) resorbable (ii) non-reactive (iii) easy to apply (iv) capable of being fixed in position. In order to fulfill these properties, we adopted solid freeform fabrication method combined with surface modification which includes the hydrogel coating, therefore, inner or outer structure can be controlled and the property of anti adhesion can be improved.

• The Journal of Korean Physical Therapy
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• v.32 no.2
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• pp.80-87
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• 2020

Purpose: Some patients who have undergone surgery due to lumbar disc herniation still complain of leg pain and other abnormal sensations. Therefore, the study examined the effects of the neurodynamics on pain and other abnormal nerve sensations in post-operated patients with lumbar disc herniation. Methods: The participants of this study comprised 20 adults (10 males and 10 females) who were diagnosed with lumbar disc herniation. The subjects were classified into two groups of 10 patients each in the lower extremity neurodynamics (LEN) and lumbar stabilization exercise (LSE) groups. Each intervention was applied twice a day for one week and was composed of two different exercise patterns; one was applied by a therapist, and the other was performed by the patients themselves. The data were analyzed using assessment methods of Digital Infrared Thermal Imaging (DITI), Toronto clinical neuropathy scoring system (TCNSS), Sympathetic Skin Response (SSR) test, and Oswestry Disability Index (ODI) scale. Results: Significant differences in TCNSS, DITI, ODI scale were observed between the LEN and LSE group (p<0.01). On the other hand, there was no significant difference in the SSR test between pre and post-treatment (p>0.05). Conclusion: The results indicated that neurodynamics treatment is effective in pain reduction and abnormal sensations, such as leg muscle cramps, in post-operated patients with lumbar disc herniation.