• Biomolecules & Therapeutics
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• v.3 no.4
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• pp.316-321
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• 1995

All the pharmacological studies of LB17522 described here were carried out with high doses (fifteen to sixty times of the therapeutic dose) to determine an indication of potential side effects in clinical use in terms of the acute clinical signs, cardiovascular and central nervous system. LB10522 does not produce any observable clinical signs except for the symptoms such as moist eye, skin rash, slight salivation, vomitting, and slightly reduced activity. The effects of LB10522 on the hemodynamics and cardiac function of anesthetized beagle dogs are as follows; heart rates and mean arterial blood pressure had a tendency to increase mildly, which is a normal finding in anesthetized dogs. All the animals except for one showed relatively stable respiratory rates throughout the observation period. Each animal treated with LB10522 showed slight increase in the left cardiac work and left ventricular stroke work which are mainly related to corresponding increases in cardiac output. Femoral blood flow were shown to be increased in some animals treated with LB10522. The epileptogenic activities of various cephalosporins were assessed by a direct intracerebral injection of appropriate concentration of test articles. The CD$_{50}$ values (nmol) obtained from the analysis of the dose-response data are as follows; 78.2, 175.3, 156.3, and 53.5 for cefazolin, cephaloridine, ceftazidime, and LB 10522, respectively. LB10522 seems to be equipotent with cefazolin or to be three times more potent than cephaloridine and ceftazidime in causing adverse CNS stimulation. Taken into consideration all the information obtained, LB10522 is not supposed to induce much changes in the functions examined in these studies in man at therapeutic doses.s.

• Journal of Veterinary Science
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• v.22 no.2
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• pp.17.1-17.13
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• 2021

Background: Klebsiella spp. is an important conditional pathogen in humans and animals. However, due to the indiscriminate use of antibiotics, the incidence of antimicrobial resistance has increased. Objectives: The purpose of this study was to investigate antimicrobial resistance in strains of Klebsiella strains and the phylogenetic relatedness of extended-spectrum cephalosporin (ESC)-resistance among Klebsiella strains isolated from clinically ill companion animals. Methods: A total of 336 clinical specimens were collected from animal hospitals. Identification of Klebsiella species, determination of minimum inhibitory concentrations, detection of ESC resistance genes, polymerase chain reaction-based replicon typing of plasmids by conjugation, and multilocus sequence typing were performed. Results: Forty-three Klebsiella strains were isolated and, subsequently, 28 were identified as K. pneumoniae, 11 as K. oxytoca, and 4 as K. aerogenes. Eleven strains were isolated from feces, followed by 10 from ear, 7 from the nasal cavity, 6 from urine, 5 from genitals, and 4 from skin. Klebsiella isolates showed more than 40% resistance to penicillin, cephalosporin, fluoroquinolone, and aminoglycoside. ESCresistance genes, CTX-M groups (CTX-M-3, CTX-M-15, and CTX-M-65), and AmpC (CMY-2 and DHA-1) were most common in the K. pneumoniae strains. Some K. pneumoniae carrying CTX-M or AmpC were transferred via IncFII plasmids. Two sequence types, ST709 and ST307, from K. pneumoniae were most common. Conclusions: In conclusion, this is the first report on the prevalence, ESCresistance genotypes, and sequence types of Klebsiella strains isolated from clinically ill companion animals. The combination of infectious diseases and antimicrobial resistance by Klebsiella in companion animals suggest that, in clinical veterinary, antibiotic selection should be made carefully and in conjunction with the disease diagnosis.

• Journal of Microbiology and Biotechnology
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• v.31 no.9
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• pp.1200-1209
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• 2021

Sepsis is an acute inflammatory response that leads to life-threatening complications if not quickly and adequately treated. Cytolysin, hemolysin, and pneumolysin are toxins produced by gram-positive bacteria and are responsible for resistance to antimicrobial drugs, cause virulence and lead to sepsis. This work assessed the effects of aloe-emodin (AE) and photodynamic therapy (PDT) on sepsis-associated gram-positive bacterial toxins. Standard and antibiotic-resistant Enterococcus faecalis, Staphylococcus aureus, and Streptococcus pneumonia bacterial strains were cultured in the dark with varying AE concentrations and later irradiated with 72 J/cm^-2 light. Colony and biofilm formation was determined. CCK-8, Griess reagent reaction, and ELISA assays were done on bacteria-infected RAW264.7 cells to determine the cell viability, NO, and IL-1β and IL-6 pro-inflammatory cytokines responses, respectively. Hemolysis and western blot assays were done to determine the effect of treatment on hemolysis activity and sepsis-associated toxins expressions. AE-mediated PDT reduced bacterial survival in a dose-dependent manner with 32 ㎍/ml of AE almost eliminating their survival. Cell proliferation, NO, IL-1β, and IL-6 cytokines production were also significantly downregulated. Further, the hemolytic activities and expressions of cytolysin, hemolysin, and pneumolysin were significantly reduced following AE-mediated PDT. In conclusion, combined use of AE and light (435 ± 10 nm) inactivates MRSA, S. aureus (ATCC 29213), S. pneumoniae (ATCC 49619), MDR-S. pneumoniae, E. faecalis (ATCC 29212), and VRE (ATCC 51299) in an AE-dose dependent manner. AE and light are also effective in reducing biofilm formations, suppressing pro-inflammatory cytokines, hemolytic activities, and inhibiting the expressions of toxins that cause sepsis.

• Genes and Genomics
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• v.40 no.12
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• pp.1383-1388
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• 2018

The development of therapeutic bacteriophages will provide several benefits based on an understanding the basic physiological dynamics of phage and bacteria interactions for therapeutic use in light of the results of antibiotic abuse. However, studies on bacteriophage therapeutics against microbes are very limited, because of lack of phage stability and an incomplete understanding of the physiological intracellular mechanisms of phage. The major objective of this investigation was to provide opportunity for development of a novel therapeutic treatment to control respiratory diseases in swine. The cytokine array system was used to identify the secreted cytokines/chemokines after Bordetella bronchiseptica infection into swine nasal turbinate cells (PT-K75). We also performed the real-time quantitative PCR method to investigate the gene expression regulated by B. bronchiseptica infection or bacteriophage treatment. We found that B. bronchiseptica infection of PT-K75 induces secretion of many cytokines/chemokines to regulate airway inflammation. Of them, secretion and expression of IL-$1{\beta}$ and IL-6 are increased in a dose-dependent manner. Interestingly, membrane-bound mucin production via expression of the Muc1 gene is increased in B. bronchiseptica-infected PT-K75 cells. However, cytokine production and Muc1 gene expression are dramatically inhibited by treatment with a specific B. bronchiseptica bacteriophage (Bor-BRP-1). The regulation of cytokine profiles in B. bronchiseptica-induced inflammation by B. bronchiseptica bacteriophage is essential for avoiding inappropriate inflammatory responses. The ability of bacteriophages to downregulate the immune response by inhibiting bacterial infection emphasizes the possibility of bacteriophage-based therapies as a novel anti-inflammatory therapeutic strategy in swine respiratory tracts.

• Clinics in Orthopedic Surgery
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• v.10 no.4
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• pp.427-432
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• 2018

Background: The purpose of this study was to evaluate the usefulness of sonication technique for microbiological diagnosis and the sterility of the recycled autoclaved femoral components from infected total knee arthroplasty (TKA) using a sonication method. Methods: Nineteen femoral implants explanted from patients with infected TKA were sterilized with a standard autoclave method. Standard culture of the fluid before and after sonication of the sterilized implants was performed to detect pathogenic microorganisms. Additional experiments were performed to evaluate the sterility of the recycled implant by inducing artificial biofilm formation. Methicillin-resistant Staphylococcus aureus (MRSA) was inoculated into 10 implants and sterilization in a standard autoclave was performed, and then the fluid was cultured before and after sonication. Results: Two of the 19 sterilized implants were positive for growth of bacteria after sonication, whereas no growth was detected in the cultured fluid from the sterilized implants before sonication. The bacteria were Staphylococcus species in all two cases. In one of 10 implants inoculated with MRSA, the culture was positive for growth of bacteria both before and after sonication. However, Staphylococcus epidermidis was cultured from both occasions and thus this implant was thought to be contaminated. Conclusions: We found sonication for identification of pathogens could be helpful, but this finding should be interpreted carefully because of the possibility of contamination. Sterilization of an infected femoral implant with an autoclave method could be a good method for using the temporary articulating antibiotic spacer in two-stage revision arthroplasty.

• Restorative Dentistry and Endodontics
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• v.44 no.3
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• pp.25.1-25.10
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• 2019

Objective: The aim of this study was to evaluate discoloration of teeth undergoing regenerative endodontic procedures (REPs) using blood clot or platelet-rich fibrin (PRF) as the scaffolds and different calcium silicate-based materials as the intracanal coronal barriers in an ex vivo model. Materials and Methods: Forty-eight bovine incisors were prepared and disinfected using 1 mg/mL double antibiotic paste (DAP). The specimens were then randomly divided into 2 groups (n = 24) according to the scaffolds (blood or PRF). After placement of scaffolds each group was divided into 2 subgroups (n = 12) according to the intracanal coronal barriers (ProRoot MTA or Biodentine). The pulp chamber walls were sealed with dentin bonding agent before placement of DAP and before placement of scaffolds. The color changes (${\Delta}E$) were measured at different steps. The data were analyzed using 2-way analysis of variance. Results: Coronal discoloration induced by DAP was not clinically perceptible (${\Delta}E{\leq}3.3$). Regarding the type of the scaffold, coronal discoloration was significantly higher in blood groups compared with PRF groups at the end of REP and after 1 month (p < 0.05). However, no significant difference was found between PRF and blood clot after 6 months (p > 0.05). Considering the type of intracanal coronal barrier, no significant difference existed between ProRoot MTA and Biodentine (p > 0.05). Conclusions: With sealing the dentinal tubules of pulp chamber with a dentin bonding agent and application of DAP as an intracanal medicament, coronal color change of the teeth following the use of PRF and blood sealed with either ProRoot MTA or Biodentine was not different at 6-month follow-up.

• Journal of Medicine and Life Science
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• v.17 no.3
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• pp.80-85
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• 2020

Urinary tract infections are among the most common infectious diseases and are the major causes of mortality and morbidity. These diseases result in many severe hospitalizations each year. Severe sepsis and septic shock are common and life-threatening medical conditions, and large cases are associated with urinary tract infection. The medical term "severe sepsis" is defined as sepsis complicated by hypotension, organ dysfunction, and tissue hypoperfusion, whereas "septic shock" is defined as sepsis complicated either by hypotension that is refractory to fluid resuscitation or by hyperlacteremia. A recent multicenter-study in Korea reported that the rate of in-hospital mortality associated with severe sepsis and septic shock was > 34%. Among the causative diseases, urogenital tract infection showed a high correlation. Moreover, it is very important that clinicians detect severe sepsis and septic shock early and treat them properly. The principles of initial treatment include provision of sufficient hemodynamic resuscitation and early administration of appropriate antibiotic therapy to mitigate uncontrolled infection. Initial resuscitation includes the use of vasopressors and intravenous fluids, and it is a key to achieve the target of initial resuscitation. Supportive care in the intensive care unit, such as glucose control, stress ulcer prophylaxis, blood transfusion, deep vein thrombosis prophylaxis, and renal replacement therapy, is also significant. We have summarized the key components in the treatment of severe sepsis and septic shock in patients with urinary tract infection. Urologists should be aware that appropriate early treatment is necessary to prevent fatal outcomes in these patients.

• Journal of Yeungnam Medical Science
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• v.39 no.1
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• pp.39-45
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• 2022

Background: The current guidelines for the diagnosis of acute pyelonephritis (APN) recommend that APN be diagnosed based on the clinical features and the presence of pyuria. However, we observed that some of the patients who are diagnosed with APN do not have characteristic clinical features or pyuria at the initial examination. We performed this study to investigate the characteristics of APN without pyuria. Methods: A retrospective, cross-sectional study was conducted on 391 patients diagnosed with APN based on clinical and radiologic findings, between 2015 and 2019. The clinical features, laboratory results, and computed tomography (CT) findings were compared between patients with normal white blood cell (WBC) counts and those with abnormal WBC counts (WBC of 0-5/high power field [HPF] vs. >5/HPF) in urine. Results: More than 50% of patients with APN had no typical urinary tract symptoms and one-third of them had no costovertebral angle (CVA) tenderness. Eighty-eight patients (22.5%) had normal WBC counts (0-5/HPF) on urine microscopy. There was a negative correlation between pyuria (WBC of >5/HPF) and previous antibiotic use (odds ratio, 0.249; 95% confidence interval, 0.140-0.441; p<0.001), and the probability of pyuria was reduced by 75.1% in patients who took antibiotics before visiting the emergency room. Conclusion: The diagnosis of APN should not be overlooked even if there are no typical clinical features, or urine microscopic examination is normal. If a patient has already taken antibiotics at the time of diagnosis, imaging studies such as CT should be performed more actively, regardless of the urinalysis results.

• Journal of Yeungnam Medical Science
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• v.40 no.3
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• pp.283-288
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• 2023

Severe chronic neutropenia is classified as severe congenital, cyclic, autoimmune, or idiopathic. However, there is a lot of uncertainty regarding the diagnosis of severe congenital neutropenia (SCN) and chronic idiopathic neutropenia, and this uncertainty affects further evaluations and treatments. A 20-year-old man presented with fever and knee abrasions after a bicycle accident. On admission, his initial absolute neutrophil count (ANC) was 30/µL. He had no medical history of persistent severe neutropenia with periodic oscillation of ANC. Although his fever resolved after appropriate antibiotic therapy, ANC remained at 80/µL. Bone marrow (BM) aspiration and biopsy were performed, and a BM smear showed myeloid maturation arrest. Moreover, genetic mutation test results showed a heterozygous missense variant in exon 4 of the neutrophil elastase ELANE: c597+1G>C (pV190-F199del). The patient was diagnosed with SCN. After discharge, we routinely checked his ANC level and monitored any signs of infection with minimum use of granulocyte colony-stimulating factor (G-CSF), considering its potential risk of leukemic transformation. Considering that SCN can be fatal, timely diagnosis and appropriate management with G-CSF are essential. We report the case of a patient with SCN caused by ELANE mutation who had atypical clinical manifestations. For a more accurate diagnosis and treatment of severe chronic neutropenia, further studies are needed to elucidate the various clinical features of ELANE.

• Journal of Korean Foot and Ankle Society
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• v.26 no.1
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• pp.30-39
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• 2022

Purpose: This study aimed to report the current trends in the management of diabetic foot over the last few decades through a survey of the Korean Foot and Ankle Society (KFAS) members. Materials and Methods: A web-based questionnaire containing 40 questions was sent to all KFAS members in September 2021. The questions were mainly related to the demographics of patients with diabetic foot, diagnostic tools, and multidisciplinary treatment. Answers with a prevalence of ≥50% of respondents were considered a tendency. Results: Seventy-eight of the 550 members (14.2%) responded to the survey. The most common demographic factors of diabetic foot patients were male dominance with a high percentage in the 60- to 70-year-old. Although the need for multidisciplinary treatment is highly recognized in the treatment of diabetic foot patients, the actual implementation rate is about 39%. The contrast-enhanced magnetic resonance imaging (88.5%) was reported to be the most used tool for the diagnosis of osteomyelitis of the diabetic foot. It was reported that the use of antibiotics was started empirically and then changed based on bacterial culture tests in 82.1% of patients. Simple wound dressing and antibiotic treatment were most frequently reported for mild ulcers. Conclusion: This study provides updated information on the current trends in the management of a diabetic foot in Korea. Both consensus and variations in the approach to patients with diabetic foot were identified by this survey study. Further efforts are required for better access to a multidisciplinary approach, such as appropriate insurance payment policies and patient education.