• Biomedical Science Letters
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• v.24 no.4
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• pp.435-438
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• 2018

Acanthamoeba culbertsoni is the causative agent of granulomatous amoebic encephalitis (GAE), a condition that predominantly occurs in immunocompromised individuals and which is typically fatal. A mannose-binding protein (MBP) among lectins was shown to have strong A. castellanii pathogenic potential when correlated with major virulence proteins. In this study, protective effects were analyzed using the monoclonal antibody to A. culbertsoni MBP by quantification and were also compared with other free-living amoebae. For the amoebial cytotoxicity to the target cell, amoeba trophozoites were incubated with Chinese hamster ovary (CHO) cells. For the protective effects of antibodies, amoebae were pre-incubated with them for 4 h and then added to the target cells. After 24 h, the supernatants were collected and examined for host cell cytotoxicity by measuring lactate dehydrogenase (LDH) release. The cytotoxicity of A. culbertsoni to the CHO cells showed about 87.4%. When the monoclonal antibody was pre-incubated with A. culbertsoni, the amoebial cytotoxicity was remarkably decreased as shown at LDH release (1.858 absorbance), which was represented with about 49.9%. Taken together, it suggested that the monoclonal antibody against MBP be important to inhibit the cytotoxicity of A. culbertsoni trophozoites to the target cell. The antibody will be applied into an in vivo functional analysis, which would help to develop therapeutics.

• Biomedical Science Letters
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• v.27 no.4
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• pp.310-316
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• 2021

Mobile phones used by healthcare workers are not only an indicator of the contamination of healthcare associated bacteria, but can also be another source of infection. The number and time of handwashing, mobile phone operation time and disinfection were highly relation with the bacterial contamination on the surface of mobile phone. Healthcare associated bacteria isolated from the mobile phone surface were 28 MRCoNS (48.3%), 14 S. aureus (24.2%), 3 MRSA (5.2%), 5 A. baumannii (8.6%), 3 MRAB (5.2%), 3 Entrococcus spp. (5.1%), 2 Pantoea spp. (3.4%), 2 A. lowffii (3.4%), 1 E. cloacae (1.7%), 1 P. stutzeri (1.7%), and P. mirabillis (1.7%). For isolation according to department, 2 MRAB from the emergency room and 1 MRSA from intensive unit, the radiology team and the rehabilitation medical team, respectively were isolated. As a result of the relation of isolates from the department of patient contact (ER, RT, GW, CP, ICU, RMT), the bacterial isolation rate was 75% and the department of patient non-contact (MRT) was 10%.

• Biomedical Science Letters
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• v.28 no.4
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• pp.284-289
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• 2022

Hypertension is associated with cardiovascular disease. The environmental and genetic factors can cause the development of hypertension. In this study, the relationship between hypertension and family history of hypertension in Koreans was analyzed in consideration of serum fasting blood glucose levels and age. The study subjects were 2,484 subjects who had a medical examination at a university hospital. The main statistical analysis method was multiple logistic regression analysis. Hypertension prevalence was 16.4% of all subjects, and subjects with a family history of hypertension were 23.5%. The risk of hypertension was 2.36 times higher in subjects with a family history of hypertension than subjects without a family history of hypertension. In addition, in the subjects with fasting blood glucose levels more than 120 mg/dL, the risk of hypertension was 4.44 times higher in subjects with a family history of hypertension compared with subjects without a family history of hypertension. The relationship between family history and hypertension was slightly higher in the older group than in the younger group. To assess the association between hypertension and family history, further cohort study is necessary in the future.

• Biomedical Science Letters
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• v.22 no.4
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• pp.115-126
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• 2016

Audiometric calibration is a prerequisite for securing the reliability of audiometric test results by checking the internal consistency of the relevant instrument. The purpose of this review is to help instrument operators understand the calibration procedure of aural acoustic immittance instrument which is frequently used for objective assessment. By referring to the latest international standards and the national standards relevant to the aural acoustic immittance instrument, the following parameters will be reviewed: 1) introduction of performance characteristics, 2) detailed procedure of the calibration method. According to the newest international and national standards [IEC 60645-5 (2004), ANSI S3.39-1987 (R2012)], the aural acoustic immittance instrument basically includes six components: 1) calibration cavity, 2) acoustic immittance analysis system, 3) probe assembly/unit and signal, 4) pneumatic air-pressure pump system, 5) acoustic reflex activator system and 6) tympanogram and acoustic reflex plotting system, each of these components should meet set standards. The result of behavioral hearing tests is influenced by various complex factors including the examinee's cooperation, background noise of the examination room, measurement method, skill level of the audiologist and calibration status, but the objective hearing tests is more influenced by the calibration status of the instrument than any other factors. The audiologist should take full responsibility for the reliability of the hearing test result, so he/she should carry out the calibration check and adjustments of aural acoustic immittance instrument periodically and maintain the instrument continuously by referring to the newest standards and the manufacturer's instruction manual.

• Biomedical Science Letters
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• v.22 no.4
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• pp.189-198
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• 2016

The purpose of this study was to examine the effect of social support on type 2 diabetes by classifying it into diabetes and impaired fasting blood sugar, a pre-diabetic state. Subjects of this study were 22,846 adults aged 30 years or above who agreed and registered to participate in the "Korean Health Examine Cohort (KOEX)" study that simultaneously collects questionnaires and biological samples at 8 university hospitals around the nation. Normal fasting blood sugar was defined as below 100 mg/dL, and impaired fasting blood sugar was defined as 100~125 mg/dL. Diagnosis of diabetes was defined as fasting blood sugar of 126 mg/dL or above, diagnosis by a doctor, or medication of insulin or oral hypoglycemic agent. Social support groups were divided into 4 groups, and Group 1 (G1) had high positive support and low negative support. This is the reference group with the highest social support. During multivariate analysis, female group (G3) that had high positive support and high negative support showed prevalence of impaired fasting blood sugar 1.19 times higher (95% CI = 1.02~1.41) than G1. As this study confirmed that social support increases fasting blood sugar of women after correction for socioeconomic status, health behavior, and biological and medical variables, it implies the importance of social relations such as social support in addition to management of personal risk factors for prevention of type 2 diabetes.

• Biomedical Science Letters
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• v.23 no.4
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• pp.411-415
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• 2017

To evaluate the protective effects of Plantago Major extract (PME) in stimulated BV-2 microglial cells and its anti-oxidant properties, cell viability assessment was performed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Lipopolysaccharide (LPS) was used to activate BV-2 microglia. Nitric oxide (NO) levels were measured using Griess assay. Tumor necrosis factor-alpha (TNF-${\alpha}$) production was evaluated by enzyme-linked immunosorbent assay (ELISA). Antioxidant properties were evaluated by 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging assay. LPS-activated excessive release of NO in BV-2 cells was significantly inhibited by PME (P < 0.001 at $100{\mu}g/mL$). PME also scavenged DPPH radicals in a dose-dependent manner (P < 0.05 at $10{\mu}g/mL$ and P < 0.001 at $20{\sim}200{\mu}g/mL$). These results indicate that PME attenuated neuroinflammatory responses in LPS-activated BV-2 microglia by inhibiting excessive production of pro-inflammatory mediators such as NO and TNF-${\alpha}$. The anti-neuroinflammatory potential of PME may be related to its strong antioxidant properties.

• Biomedical Science Letters
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• v.23 no.4
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• pp.348-354
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• 2017

TyG (triglyceride and glucose) index using triglyceride and fasting blood glucose is recommended as a useful marker for insulin resistance. The present study evaluated the usefulness of TyG index in diagnosing metabolic syndrome and suggested an optimal cut-off value. The subjects of this study were adult 4,415 adults aged 20 to 80 years who underwent health screening at J General Hospital from January 2016 to January 2017. Metabolic syndrome was based on AHA/NHLBI (American Heart Association/National Heart, Lung, and Blood Institute) criteria. TyG index correlated with metabolic syndrome risk factors including HOMA-IR. Compared with the participants in the lowest quartile of TyG index, odds ratios and 95% confidence intervals for metabolic syndrome were 8.5 (3.005~23.903), 20.0 (17.190~23.407) for those in the third, and the fourth quartile of TyG index. The optimal cut-off value of the metabolic syndrome was 8.81 for TyG index (sensitivity 86.7%, specificity 80.1%) and area under the ROC curve (AUC) was 0.894. In conclusion, TyG index is effective to identify individuals at risk for metabolic syndrome.

• Biomedical Science Letters
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• v.20 no.3
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• pp.147-155
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• 2014

It has well studied that immune cells are strongly related to tumor progression and tumor suppression. To identify the difference of immune cell between tumor bearing mice and normal mice, we examined systemically the immune cell of CT26 tumor bearing mice on 21 days after tumor cell administration. As previously reported, CD4+ and CD8+ T cells population of tumor bearing mice significantly decreased 38% and 30% on day 21 compared to that of normal mice, respectively. All subpopulation of CD4 and CD8+ T cell significantly decreased, except CD49b+ T cell subpopulation. But, myeloid cell population ($CD11b^{high}$ and all Gr-1+ subpopulation) of tumor bearing mice significantly increased on day 21. Especially, all subpopulation of CD11b+Gr-1+ cell of tumor bearing mice significantly increased on day 21. Also, Foxp3+$CD25^{high}$ CD4 T cell (regulatory T cells) population significantly increased on day 21. These results suggest that tumor can induce the decline of T lymphocyte and the expansion of myeloid cells and regulatory T cells, and provide the basic information for the study of tumor immunology.

• Biomedical Science Letters
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• v.25 no.4
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• pp.367-371
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• 2019

In this study, the author observed the fungal characteristics of T. verrucosum which is commonly known as the cattle ringworm fungus in the farms of Hoengseong, Gangwon-do. After isolating 20 strains of T. verrucosum from cattle, they were cultured on SDA, PDA media and the fungal characteristics were concluded through visual observation of the colonies, microscopic findings, hair perforation test and urease test. The size of the colonies cultured on SDA media at 37 C was on an average 5 mm at 1 week, 33 mm at 2 weeks, 42 mm at 3 weeks and 58 mm after 4 weeks. Observing the characteristics of the colonies, 17 strains of T. album showing central bold radial folds, 2 strains of T. ochraceum having l throughout the colonies and 1 strain of T. discoides with rapid growth rate and gray-white cotton patterns were found. On microscopic observations of the cultured colonies on SDA, PDA media, macroconidia and microconidia were not found in T. verrucosum and hyphae and chlamydospore were only seen in T. album types. Out of 20 strains of T. verrucosum, hair perforation test was positive on only 3 strains and urease test was positive on all of the 20 strains.

• Biomedical Science Letters
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• v.25 no.4
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• pp.321-330
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• 2019

Carbapenem is recently considered as the last resort of the therapeutics for gram negative bacterial infection. Increasing of organisms producing metallo-β-lactamase (MBL), we have difficulty in choosing the antimicrobial agents. Among 345 clinical isolates of Pseudomonas spp., 61 isolates (17.7%) were positive for the modified imipenem or meropenem-Hodge test and 55 isolates (15.9%) were positive for the imipenem-EDTA + SMA double disk synergy test (DDS). PCR and sequencing of bla_VIM-2-allele and bla_IMP-1-allele showed that 17 isolates of Pseudomonas aeruginosa, 9 isolates of Pseudomonas taiwnensis and 2 Pseudomonas plecoglossicida had bla_VIM-2, and 22 isolates of P. aeruginosa and one Pseudomonas otitidis had bla_IMP-6. These MBL genes were all in class 1 integron. The size of class 1 integron with bla_VIM-2 ranged from 3.5 kb to 5.5 kb in clinical isolates of Pseudomonas spp. including P. aeruginosa. bla_VIM-2 was most often located first in the class 1 integron, sometimes in the second or third position, and these integrons often had aacA4 or aadA1. Strict infection control measures are needed to more effectively prevent further spread of these MBL-producing Pseudomonas spp. In addition, MBL-producing Pseudomonas spp. is expected to continue to spread in various countries and regions.