1.Homogenic Evaluation for Spatial Distribution in Osteoclast Differentiation
Hyun-Sook LIM ; Hong-In SHIN ; Daewon JEONG
Journal of Bone Metabolism 2022;29(4):265-269
Background:
Cells have heterogeneous cellular diversity in size, morphology, cell cycle, metabolism, differentiation degree, and spatial distribution. The shift of specific cells towards the desired cells is crucial for maintaining uniform cellular function and can be represented by homogeneity and heterogeneity. Here, we developed a simple and direct method for evaluating the homogeneous distribution of desired cells in a constant region.
Methods:
We differentiated osteoclast progenitors into bone-resorbing multinucleated giant osteoclasts in a 2-dimensional culture plate under 2 conditions. Cells were stained with tartrate-resistant acid phosphatase to assess osteoclast differentiation, images were taken using a microscope and divided into sectors, and the number of osteoclasts (≥3 nuclei) in each sector was counted. To assess the homogeneity of the spatial distribution of osteoclasts, the standard deviation (SD) was calculated from the mean number of osteoclasts within each sector.
Results:
From the 2 groups, a value with a SD close to 0 indicates high spatial homogeneity while a relatively high SD represents low spatial homogeneity.
Conclusions
Our findings suggest that spatial homogeneity can be represented as SD.
2.Evaluation of the Analytical Performance of Atellica CH 930 Automated Chemistry Analyzer
Daewon KIM ; Yonggeun CHO ; Jooyoung CHO ; Sun hee KIM ; Sang Guk LEE ; Jeong Ho KIM
Laboratory Medicine Online 2019;9(3):133-145
BACKGROUND: Recently, a new automated chemistry analyzer, Atellica CH930 (Siemens, Germany), was introduced. It automatically measures internal quality control (QC) materials according to a pre-determined schedule. For this purpose, the instrument has space for storage of QC materials. We evaluated the analytical performance of chemistry items by using the Atellica system. METHODS: The precision of 29 items was evaluated with three levels of QC materials with two storage methods. We stored the QC materials in the dedicated storage space in the instrument during the precision evaluation period. In addition, we aliquoted and stored the materials in the refrigerator, and then loaded the material in a timely manner. Linearity, carry-over, and agreement with current methods were also evaluated. RESULTS: The within-laboratory coefficient of variation (CV) of most items, except for total CO2 (tCO2), was within 5.0% in both QC storage methods without significant differences in CV between storage methods. The CV of tCO2 was 5.2%, 5.8%, and 5.1% at three different levels when the QC materials were stored in a dedicated space in the instrument. The linearity was acceptable, showing <5% nonlinearity. Although good agreement was observed for most items, some items, such as calcium, total bilirubin, aspartate transaminase, and chloride, showed unequivalent results. CONCLUSIONS: Atellica CH930 showed acceptable precision, linearity, and agreement in routine chemistry items. The automatic QC function using the storage device has no problem with stability or precision. It can reduce the manual process, allowing technicians to focus on reviewing the QC results and reporting reliable results.
Appointments and Schedules
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Aspartate Aminotransferases
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Bilirubin
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Calcium
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Chemistry
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Quality Control
3.Influence of COVID-19-related Nursing Experience on Job Stress of Nurses
Yeon Hee KIM ; Hyun Sil JOO ; Jeong Eon LEE ; Mi Sun LEE
Korean Journal of Occupational Health Nursing 2022;31(4):147-156
Purpose:
This study aimed to compare and analyze the job stress of nurses with and without in COVID-19-related work.
Methods:
A structured self-reported questionnaire survey was conducted to assess job stress. The extent of job stress was compared between nurses with COVID-19 (COVID-19 group) and those without such experience (non-COVID-19 group). Multiple regression analysis was performed to identify the factors influencing job stress.
Results:
Job stress was higher in the COVID-19 group compared to the non-COVID-19 group (t=2.54, p=.12). In sub-categorical comparison, stress driven by a taxing work environment, relationship conflict, and work schedule was higher in the COVID-19 group than the non-COVID-19 group. Multiple regression analysis revealed the job stress was higher among nurses with COVID-19-related work experience than that of non-experienced nurses. The factors affecting job stress of nurses with COVID-19-related work experience included emergency room work, providing nursing assistant for COVID-patients, and caring for these patients.
Conclusion
Since COVID-19-related work experience is a major factor that affects nurses' job stress, it is imperative to provide various support measures for nursing assistants such as providing a break from working in an environment with high risk of infection, adjusting work schedules, resolving conflicts between personnel, and securing support.
4.Transfusion in RhD Mismatch Hematopoietic Stem Cell Transplantation
Daewon KIM ; Kyung-Hee KIM ; Yiel-Hea SEO ; Pil-Whan PARK ; Jeong-Yeal AHN ; Ja Young SEO
Korean Journal of Blood Transfusion 2020;31(2):159-164
In some cases, hematopoietic stem cell transplants (HSCT) show differences in the D antigen. In previous studies, there have been few cases of de novo anti-D alloimmunization, and even rarer cases of serious side effects or the outcomes. De novo anti-D alloimmunization has been reported to occur more frequently in minor D mismatch than in major D mismatch. For the RhD type of blood components, RhD-negative type is recommended in transfusion in RhD mismatch HSCT without anti-D in donors and recipients. But in situations of insufficient RhD-negative blood supply, this study suggests that the RhD type of blood components depends on the patients’ RhD type before transplantation, and it depends on the donors’ RhD type after transplantation, and an RhD-positive platelet transfusion may be available.
5.Analysis of blood culture data in Korea: bacterial distribution and cumulative antimicrobial resistance (2016–2020)
Yiel Hea SEO ; Daewon KIM ; Hwan Tae LEE ; Ja Young SEO ; Jeong Yeal AHN ; Pil Whan PARK
Annals of Clinical Microbiology 2023;26(4):147-157
Background:
The distribution of bacteria isolated from bloodstream infections and cumulative antimicrobial susceptibility data are the basis for empirical decisions regarding antibiotics as an initial treatment. Therefore, it is important to consistently collect blood culture results of individual patients and analyze them correctly.
Methods:
The blood culture results of patients at a university hospital from 2016 to 2020 were analyzed retrospectively to determine the bacterial distributions and antibiotic resistance patterns. Duplicates were eliminated by including only the first isolate of each species per patient.
Results:
Escherichia coli (27.1%) was the most commonly isolated bacterium from blood cultures, followed by Klebsiella pneumoniae (10.1%) and Staphylococcus aureus (8.6%). The methicillin resistance rate of S. aureus was 49.2%, and the vancomycin resistance rate of Enterococcus faecium was 39.5%; with no significant changes over the study period. The cefotaxime, ciprofloxacin, and ertapenem resistance rates of E. coli were 35.0%, 46.8%, and 0.7%, respectively. Seventeen carbapenem-resistant E. coli strains were isolated, of which 11 produced carbapenemase. The cefotaxime, ciprofloxacin, and ertapenem resistance rates of K. pneumoniae were 29.5%, 31.7%, and 5.4%, respectively. Forty-eight carbapenem-resistant K. pneumoniae strains were isolated, of which 37 produced carbapenemase. The imipenem resistance rates of Acinetobacter baumannii and Pseudomonas aeruginosa were 72.3% and 23.4%, respectively.
Conclusion
In the blood culture results from 2016 to 2020, the isolation frequency of E.coli, K. pneumoniae, and E. faecium showed an increasing trend, whereas that of S. aureus was stable. Over the 5 year study period, the ciprofloxacin resistance rate of E. coli and P.aeruginosa and ampicillin/sulbactam resistance rate of A. baumannii significantly increased.