• Parasites, Hosts and Diseases
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• 제22권2호
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• pp.153-160
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• 1984

마우스에 대한 요꼬가와흡충 실험감염에 있어서 충체회수률 등 감수성(susceptibility)이 실험자에 따라 매우 다른 것으로 보고되어 있다. 저자등은 이것이 마우스 strain에 따른 차리일 것으로 생각하고 이 연구를 통하여 확인하고자 하였으며, 또 prednisolone 주입으로 숙주의 면역반응을 저하시킬 때 충체회수률이 어떻게 변동하는가를 관찰하고자 하였다. 요꼬가와흡충 피낭유충은 은어의 근육으로부터 분리한 것을 사용하였으며 마우스 5개 strain (A,DBA,CBH,CSTBL,KK) 총 60마리에 대해서 300개씩의 피낭유충을 감염시키고 1주일 후에 도살하여 충체회수률 및 충체의 크기를 측정하였다. 또 ICR계 마우스 29마리에는 각각 1,800개씩의 피낭유충을 감염시키되 그중 15마리에 대해서는 감염 1주전부터 도살시까지 격일로 prednisolone l0mg/kg를 주입하였고 각각 감염 6시간부터 35일까지의 충체회수율을 관찰하였다. 결과는 다음과 같다. 1. 마우스 5개 strain에 있어서 감염성공률은 25.0∼83.3%의 범위에서 차이를 보였고, 충체국수률은 1.2∼18.9%, 나수충체의 크기는 평균 길이 0.554∼0.683mm, 폭 0.214∼0.244mm이었다. 이들 수치는 KK 및 CSTBL strain에서 다른 3가지 strain보다 높았으며 유의한 차리를 보였다. 2. ICR계 마우스에서 시간별로 관찰한 충체회률은 감염 1일이내에는 38∼66%의 높은 율을 보였으나 1일 이후에는 35일까지 0.7%이하의 낮은 회수률을 보였다. 그러나 prednisolone을 투여한 군에서는 감염후 21일까지도 16∼80%의 높은 충체회수률을 유지하였다. 이상의 결과로 미루어 보아 마우스는 strain에 따라 요꼬가와흡충 감염에 대한 감수성이 다르다 것을 알 수 있었다. 또한 감수성이 낮은 ICR계 마우스도 prednisolone을 주입하면 감염 3주까지 높은 충체회수률을 얻을 수 있음을 알게 되었다.

• Archives of Plastic Surgery
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• 제33권3호
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• pp.330-334
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• 2006

Polymicrobial nature of diabetic foot infection has been well documented in the literature. Initial antibiotic therapy of diabetic foot infection is usually empiric until reliable culture data is shown. This study was carried out to determine the common bacteriological flora of diabetic foot infection and antimicrobial sensitivity pattern in order to enhance possible empiric treatment. The specimens were obtained from wounds of 207 cases of diabetic foot ulcer, and the bacteriological isolation, and antimicrobial susceptibility tests of the isolates were carried out by standard microbiological methods. Staphylococcus aureus was the most common isolate, with 46.2% of recover rate among total bacterial isolated cases. Among gram-negative organisms, Pseudomonas aeruginosa was most common. Gram-positive organisms showed significant susceptibility to clindamycin, trimethoprim/sulfamethoxazole, and levofloxacin, besides vancomycin. Cefoperazone, piperacillin/tazobactam, and amikacin in addition to imipenem were most effective agents compared to gram-negative organisms. Diabetic foot infection requires use of combined antimicrobial therapy for initial management. Our results indicate that the most effective antibiotic combination for diabetic foot infection of Korean patients is clindamycin plus cefoperazone.

• 한국임상수의학회지
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• 제3권1호
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• pp.243-253
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• 1986

In recent years much attention has been paid to swine respiratory infection caused by Haemophilus(H.) Pleuropneumoniae with rapid expansion of pork industry in Korea. The organism may cause an acute respiratory infection with high morbidity and mortality, or it may also cause chronic persistent infection, resulting in loss of body weight. The present study was performed to observe the etiologic situation of H. Pleuropneumoniae infection by evaluating bacteriological, serological examinations with the lungs and sera collected from slaughtered pigs in Daegu city, respectively. In addition, antibiotic susceptibility test was carried out against the isolated strains of H. Pleuropneumoniae. The results obtained are summarized as follows : 1. Only 10 strains of H. Pleuropneumoniae were isolated from the 120 cases of swine lungs examined, and biological and biochemical characteristics of the isolates were identical with that of standard strains(serovar 1 to 6). 2. Out of 336 swine sera examined, 108(32.1%) were shown to be positive against H. Pleuropneumoniae by latex agglutination test. 3. Antibiotic susceptibility test revealed that 10 isolates of H. Pleuropneumoniae were sensitive to 16 kinds of antibiotic such as ampicillin, benzylpenicillin, piperacillin, cephalothin, cefazolin, cefamandol, cefoperagon, lactomoxycefa, tetracycline, minocycline, chloramphenicol, gentamicin, kanamycin, amikacin, colistin and nalidixic acid, whereas cloxacillin, erythromycin, kitasamycin, lincomycin, oleand-amycin, and bacitracin were resistent.

• Clinical and Experimental Pediatrics
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• 제54권2호
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• pp.79-85
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• 2011

Purpose: We studied the differences in the antibiotic susceptibilities of the microorganisms that causeing urinary tract infections (UTI) in children to obtain useful information on appropriate drug selection for childhood UTI. Methods: We retrospectively analyzed the antibiotic susceptibilities of 429 microorganisms isolated from 900 patients diagnosed with UTI in the Department of Pediatrics, Chungbuk National University Hospital, from 2003 to 2008. Results: The most common causative microorganisms for UTI were Escherichia coli (81.4%), Klebsiella pneumoniae (8.4%), Enterobacter spp. (1.7%), and Proteus spp. (0.4%). E. coli showed relatively high susceptibility as compared to imipenem (100%), amikacin (97.7%), aztreonam (97.9%), cefepime (97.7%), and ceftriaxone (97.1%), while it showed relatively low susceptibility to gentamicin (GM) (79.0%), trimethoprim/sulfamethoxazole (TMP/SMX) (68.7%), ampicillin/sulbactam (33.0%), and ampicillin (AMP) (28.6%). There were no significant differences in the image findings for causative microorganisms. Conclusion: Gram-negative organisms showed high susceptibility to amikacin and third-generation cephalosporins, and low susceptibility to AMP, GM, and TMP/SMX. Therefore, the use of AMP or TMP/SMX as the first choice in empirical and prophylactic treatment of childhood UTI in Korea should be reconsidered and investigated further.

• Childhood Kidney Diseases
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• 제21권2호
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• pp.128-135
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• 2017

Purpose: Extended-spectrum ${\beta}$-lactamase-producing bacteria-induced urinary tract infections are increasing and require more potent antibiotics such as carbapenems. We evaluated the clinical significance of extended-spectrum ${\beta}$-lactamase -urinary tract infection in children younger than 5 years to select proper antibiotics and determine prognostic factors. Differences were compared between age groups. Methods: We retrospectively studied 288 patients with their first febrile urinary tract infection when they were younger than 5 years. Patients were divided into extended-spectrum ${\beta}$-lactamase-positive and extended-spectrum ${\beta}$-lactamasenegative urinary tract infection groups. Clinical characteristics and outcomes were compared between the groups; an infant group was separately analyzed (onset age younger than 3 months). Results: Extended-spectrum ${\beta}$-lactamase urinary tract infection occurred in 11 % patients who had more frequent previous hospitalization (P=0.02) and higher recurrence rate (P=0.045). During the antimicrobial susceptibility test, the extended-spectrum ${\beta}$-lactamase-positive urinary tract infection group showed resistance to third-generation cephalosporins; however, 98% patients responded clinically. In the infant group, extended-spectrum ${\beta}$-lactamase-positive urinary tract infection occurred in 13% patients and was associated with a longer pre-onset hospitalization history (P=0.002), higher C-reactive protein level (P=0.04), and higher recurrence rate (P=0.02) than that in the older group. Conclusion: Extended-spectrum ${\beta}$-lactamase urinary tract infection requires more attention because of its higher recurrence rate. The antimicrobial susceptibility test demonstrated resistance to third-generation cephalosporins, but they can be used as first-line empirical antibiotics because of their high clinical response rate. Aminoglycosides can be second-line antibiotics before starting carbapenems when third-generation cephalosporins do not show bactericidal effects for extended-spectrum ${\beta}$-lactamase urinary tract infection.

• 한국어병학회지
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• 제36권2호
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• pp.213-228
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• 2023

We evaluated the transcriptional response of interferon (IFN)-related genes in rock bream iridovirus (RBIV)-infected rock bream under high-, low-, or no-mortality conditions induced by different stocking water temperatures. Under the high susceptibility condition (group A, water temperature 26℃, 100% mortality), only the Mx gene was expressed early, with prolonged expression, and with heavy viral loads of approximately 10⁶~10⁷ major capsid protein gene copies/μL from 4 to 10 days post infection (dpi). However, IRF1, IRF3, IRF8, STAT1, ISG15, PKR, Viperin, GVIN1, IFI44, and ISG56 were activated at later time points (8 dpi) and then quickly decreased (10 dpi). For the low susceptibility condition, the water temperature was set at 23℃ for 7 days (group B) and then reduced to 17℃. Group B exhibited a 28% mortality rate, in which persistent and effective antiviral responses were observed for long periods of time. In particular, at 20 and 22 dpi, when virus replication was peaked at approximately 10⁷/μL, the expressions of most of the IFN-related genes (IRF1, IRF3, IRF8, Mx, STAT1, ISG15, PKR, Viperin, GVIN1, IFI44, and ISG56) were significantly higher in group B than in the control group. Moreover, prolonged and higher levels of IRF3 (at least 30 dpi), IRF8 (at least 30 dpi), ISG15 (at least 30 dpi), PKR (at least 28 dpi), Viperin (at least 30 dpi), and IFI44 (at least 30 dpi) were also observed in the recovery stage of infection. Under the no-susceptibility condition at 17℃ (0% mortality), significantly elevated levels of IRF3, Mx, ISG15, and PKR were observed mostly until 20 dpi. The findings indicate that RBIV infection can induce an efficient IFN-mediated antiviral immune response in low- and no-susceptibility conditions. The findings could be valuable for effective control of viral pathogens in fish.

• Parasites, Hosts and Diseases
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• 제61권2호
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• pp.138-146
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• 2023

Toxoplasma gondii is an intracellular protozoan parasite which can infect most warm-blooded animals and humans. Among the different mouse models, C57BL/6 mice are more susceptible to T. gondii infection compared to BALB/c mice, and this increased susceptibility has been attributed to various factors, including T-cell responses. Dendritic cells (DCs) are the most prominent type of antigen-presenting cells and regulate the host immune response, including the response of T-cells. However, differences in the DC responses of these mouse strains to T. gondii infection have yet to be characterized. In this study, we cultured bone marrow-derived DCs (BMDCs) from BALB/c and C57BL/6 mice. These cells were infected with T. gondii. The activation of the BMDCs was assessed based on the expression of cell surface markers and cytokines. In the BMDCs of both mouse strains, we detected significant increases in the expression of cell surface T-cell co-stimulatory molecules (major histocompatibility complex (MHC) II, CD40, CD80, and CD86) and cytokines (tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-12p40, IL-1β, and IL-10) from 3 h post-T. gondii infection. The expression of MHC II, CD40, CD80, CD86, IFN-γ, IL-12p40, and IL-1β was significantly higher in the T. gondii-infected BMDCs obtained from the C57BL/6 mice than in those from the BALB/c mice. These findings indicate that differences in the activation status of the BMDCs in the BALB/c and C57BL/6 mice may account for their differential susceptibility to T. gondii.

• 한국임상수의학회지
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• 제38권5호
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• pp.225-230
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• 2021

A 4-year-old gelding Thoroughbred racehorse, which had been undergoing antibiotic therapy at a local veterinary clinic, was referred to the KRA veterinary center with a 20-day history of continuous right nasal discharge. Patient's history, endoscopic examination, and radiographic examination revealed primary maxillary sinusitis. Under sedation, surgical intervention was performed to collect samples and remove the accumulated mucopurulent exudate in the sinus. Swab samples were collected from the sinus during surgery for cytology and antimicrobial susceptibility testing. Only one type of bacteria was cultured, and molecular analyses of 16S ribosomal RNA gene sequences identified it as Staphylococcus aureus (S. aureus). The isolate was resistant to multiple antibiotics, which are frequently used in equine practice. Trimethoprim-sulfamethoxazole was chosen based on antibiotic susceptibility test, trephination, and sinus lavage using saline were applied to treat bacterial sinusitis. The clinical signs improved after 1 month and the patient resumed training. This report describes S. aureus isolated from bacterial maxillary sinusitis in a horse and its antibiotic susceptibility.

• Nutrition Research and Practice
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• 제15권sup1호
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• pp.1-21
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• 2021

The coronavirus disease 2019 (COVID-19) pandemic has put focus on the importance of a healthy immune system for recovery from infection and effective response to vaccination. Several nutrients have been under attention because their nutritional statuses showed associations with the incidence or severity of COVID-19 or because they affect several aspects of immune function. Nutritional status, immune function, and viral infection are closely interrelated. Undernutrition impairs immune function, which can lead to increased susceptibility to viral infection, while viral infection itself can result in changes in nutritional status. Here, we review the roles of vitamins A, C, D, and E, and zinc, iron, and selenium in immune function and viral infection and their relevance to COVID-19.

• 미생물학회지
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• 제22권2호
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• pp.111-118
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• 1984

The changes of susceptibility of Bacillus subtilis SNU816 to bacteriophage SP816 were investigated. When B. sutilis SNU816 cells were infected by the phage during vegetative growth, rapid lysis was observed. But when they were infected after late logarismic phase, they were resistant to phage infection. Since asporogenic culture of this strain was invariably lysed regardless of time of infection, the arrest of phage multiplication seemed to be caused by sporulation. In reality, the arrest of phage multiplication occurred at early stage of sporulation. Electron microscopy revealed that the arrest of phage multiplication occurred just prior to or during septum formation (stage II sporulation).