• Journal of applied mathematics & informatics
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• v.27 no.3_4
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• pp.779-793
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• 2009

This paper deals with a delayed SEIRS epidemic model with pulse vaccination and crowded incidence rate. Moreover, the case of vertical and horizontal transmission is considered. By using the discrete dynamical system determined by the stroboscopic map, the exact infection-free periodic solution of the SEIRS model is obtained. Further, by employing the comparison arguments, we prove that under the condition that $R_*$ < 1 the infection-free periodic solution is globally attractive, and that under the condition that $R^*$ > 1 the disease is uniformly persistent, which means that after some period of time the disease will become endemic.

• Parasites, Hosts and Diseases
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• v.25 no.2
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• pp.185-187
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• 1987

Thia report deals with an imported case of calamar swelling suspective of loiasis, who had been in Nigeria, Africa for 2 years. This 33-year-old Korean technician was admitted to Severance Hospital, Yonsei University Medical Center, because of erythematous swellings on left hand and foot. His peripheral blood showed persistent eosinophilia (over 30% of WBC), increased IgE(1,000unit/ml) and significantly high antialarial antibody titer with ensyme immunoassay, although no microfilaria was detected on the periplleral blood films. Under the impression of Loa lea infection diethylcarbamasine was administered for a month. Four months later mobile swellings and eosinophilia disappeared, and anti-filarial antibody titers were normalized. It is assumed that the patient had suffered from Loa lea infection, which is the first report on loiasis in Korea.

• Journal of Microbiology and Biotechnology
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• v.31 no.10
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• pp.1350-1357
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• 2021

Staphylococcus aureus (S. aureus) is a major pathogen that causes human pneumonia, leading to significant morbidity and mortality. S. aureus coagulase (Coa) triggers the polymerization of fibrin by activating host prothrombin, which then converts fibrinogen to fibrin and contributes to S. aureus pathogenesis and persistent infection. In our research, we demonstrate that isovitexin, an active traditional Chinese medicine component, can inhibit the coagulase activity of Coa but does not interfere with the growth of S. aureus. Furthermore, we show through thermal shift and fluorescence quenching assays that isovitexin directly binds to Coa. Dynamic simulation and structure-activity relationship analyses suggest that V191 and P268 are key amino acid residues responsible for the binding of isovitexin to Coa. Taken together, these data indicate that isovitexin is a direct Coa inhibitor and a promising candidate for drug development against S. aureus infection.

• Archives of Plastic Surgery
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• v.49 no.5
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• pp.604-607
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• 2022

Nontuberculous mycobacterial hardware infections are extremely challenging to treat. Multidisciplinary care involving removal of infected hardware, thorough debridement, and durable soft tissue coverage in conjunction with antibiotic therapy is essential for successful management. This case report presents a patient with chronic mycobacterial spinal hardware infection that underwent successful treatment with aggressive serial debridements and reconstruction with a large pedicled superior gluteal artery perforator flap coverage.

• Archives of Plastic Surgery
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• v.51 no.1
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• pp.135-138
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• 2024

A patient suffered from chronic ulcer due to recalcitrant fungal infection for 3.5 years. Five antifungal agents and 40 times of debridement—all failed. Finally, radical microscopic debridement was performed for eradication of fungal conidiospores. Since then, there was no recurrence at 2 years of follow-up. Scopulariopsis brevicaulis is one of the rarest pathogens of cutaneous fungal infections, for which multidrug resistance increased the complexity and difficulty of treatment. Radical excision, especially microscopic debridement, was the key for eradication of fungal conidiospores in this case.

• IMMUNE NETWORK
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• v.10 no.4
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• pp.120-125
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• 2010

Dysfunction of the virus-specific T cells is a cardinal feature in chronic persistent viral infections such as one caused by hepatitis C virus (HCV). In chronic HCV infection, virus-specific dysfunctional CD8 T cells often overexpress various inhibitory receptors. Programmed cell death 1 (PD-1) was the first among these inhibitory receptors that were identified to be overexpressed in functionally impaired T cells. The roles of other inhibitory receptors such as cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) and T cell immunoglobulin and mucin domain-containing molecule 3 (Tim-3) have also been demonstrated in T-cell dysfunctions that occur in chronic HCV patients. Blocking these inhibitory receptors in vitro restores the functions of HCV-specific CD8 T cells and allows enhanced proliferation, cytolytic activity and cytokine production. Therefore, the blockade of the inhibitory receptors is considered as a novel strategy for the treatment of chronic HCV infection.

• Korean Journal of Head & Neck Oncology
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• v.38 no.1
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• pp.59-63
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• 2022

The latissimus dorsi flap has high vascularity and is helpful for the reconstruction of infected areas. Herein, we present a patient with recurrent infections and soft-tissue defects who underwent cranial reconstruction using a free latissimus dorsi flap. The patient had undergone craniectomy and reconstruction using alloplastic bone 18 years previously. A scalp defect accompanied by infection occurred five years ago, and patient underwent reconstruction using a free flap at another hospital; however, the problem persisted. After debridement and bone flap removal, the right latissimus dorsi musculocutaneous flap was elevated, and the thoracodorsal artery and vein were anastomosed end-to-end to the right superficial temporal artery and vein. Methicillin-resistant Staphylococcus aureus was eradicated, and the flap survived. Cranioplasty was performed eight months later, and one year follow-up proceeded without complications. Effective reconstruction and cranioplasty are possible using the free latissimus dorsi musculocutaneous flap, even on scalp with persistent infections and soft-tissue defects.

• Imaging Science in Dentistry
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• v.52 no.4
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• pp.435-440
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• 2022

Mucormycosis is a rare, invasive fungal infection that progresses aggressively and requires prompt surgery and appropriate treatment. The number of cases of mucormycosis in coronavirus disease 2019 (COVID-19) patients has recently increased, and patients with uncontrolled diabetes mellitus are particularly at an elevated risk of infection. This report presents a case of mucormycosis-related osteomyelitis of the maxilla in a 37-year-old man with diabetes mellitus. The patient complained of severe and persistent pain in the right maxilla, accompanied by increased tooth mobility and headache. On contrast-enhanced computed tomographic images, gas-forming osteomyelitis of the right maxilla was observed. Destruction of the maxilla and palatine bone then proceeded aggressively. Sequestrectomy was performed on the right maxilla, and the histopathological diagnosis was mucormycosis. Further investigation after the first operation revealed the patient's history of COVID-19 infection.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.12
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• pp.8908-8914
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• 2015

The Internet continues to grow and develop, but there are going to generate a variety of Internet attacks that exploit it. In the initial Internet environment, the attackers maliciously exploited Internet environments for ostentations and hobbies. but these days many malicious attempts purpose the financial gain so systematic and sophisticated attacks that are associated with various crimes are occurred. The structures, such as viruses and worms were present in the form of one source multi-target before. but recently, APT(Advanced Persistent Threat, intelligent continuous attacks) in the form of multi-source single target is dealing massive damage. The performance evaluation analyzed whether to generate audit data and detect integrity infringement, and false positives for normal traffic, process detecting and blocking functions, and Agent policy capabilities with respect to the application availability.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.325-332
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• 1986

Since Combes' first description of hepatitis B virus associated membranous glomerulonephritis, many reports have shown a strong association of hepatitis B virus infection with various types of nephropathies, especially membranous glomerulonephritis and membranoproliferative glomerulonephritis. Recently, the authors experienced a case of membraoproliferative glomerulonephritis, type I in a 16-year-old male patient with persistent HBs and HBe antigenemia. One year prior to admission the patient was told of hepatitis at routine check, but he remained asymptomatic throughout. He was admitted to our hospital with chief complaints of proteinuria and microscopic hematuria found on routine urinalysis. Liver and kidney biopsy revealed chronic persistent hepatitis and membranoproliferative glomerulonephritis type I, respectively. We report a case of hepatitis B virus associated nephropathy with review of the literatures. Considering the endemic nature of hepatitis B virus infection in Korea, the incidence of hepatitis B viurs associated nephropathy would be proportionally high in comparison with those of other countries. So, the importance of this entity merits special consideration in our country. Further study concerning pathogenesis, epidemiology, and treatment may be needed.