Evaluation of Multiplex Rapid Antigen Test for the Detection of SARS-CoV-2 and Influenza A/B in Respiratory Samples.

BACKGROUND: There is little data about the performance of multiplex rapid antigen tests (RATs) on the detection of SARS-CoV-2, influenza A (Flu A), and influenza B (Flu B). This study is to evaluate the performance of Panbio COVID-19/Flu A&B rapid panel (Abbott Diagnostics, Korea) and analyze the factors influencing its sensitivity. METHODS: Nasopharyngeal swabs were collected and stored at the Korea University Anam hospital. In total, 400 residual samples from nasopharyngeal swabs were examined. The diagnostic accuracy of RAT was compared to that of RT-qPCR using the Allplex SARS-CoV-2/FluA/FluB/RSV Assay (Seegene, Seoul, South Korea). RESULTS: Panbio COVID-19/Flu A&B rapid panel showed the sensitivities of 88.0%, 92.0%, and 100% for SARS-CoV-2, Flu A, and Flu B, respectively, and specificities of 100% for all. The agreements with previously licensed single-plex RATs were shown to be high. In the analysis of variables affecting sensitivity, inappropriate sampling time after symptom onset (STASO) and high cycle threshold (Ct value) were shown to negatively affect the sensi-tivity. CONCLUSIONS: In conclusion, the multiplex RAT is useful for diagnosing SARS-CoV-2 and Flu A/B, but more clinical studies are needed.

Rapid Direct Identification of Microbial Pathogens and Antimicrobial Resistance Genes in Positive Blood Cultures Using a Fully Automated Multiplex PCR Assay.

This study assessed the performance of the BioFire Blood Culture Identification 2 (BCID2) panel in identifying microorganisms and antimicrobial resistance (AMR) profiles in positive blood cultures (BCs) and its influence on turnaround time (TAT) compared with conventional culture methods. We obtained 117 positive BCs, of these, 102 (87.2%) were correctly identified using BCID2. The discordance was due to off-panel pathogens detected by culture (n = 13), and additional pathogens identified by BCID2 (n = 2). On-panel pathogen concordance between the conventional culture and BCID2 methods was 98.1% (102/104). The conventional method detected 19 carbapenemase-producing organisms, 14 extended-spectrum beta-lactamase-producing Enterobacterales, 18 methicillin-resistant Staphylococcus spp., and four vancomycin-resistant Enterococcus faecium. BCID2 correctly predicted 53 (96.4%) of 55 phenotypic resistance patterns by detecting AMR genes. The TAT for BCID2 was significantly lower than that for the conventional method. BCID2 rapidly identifies pathogens and AMR genes in positive BCs.

Breathing-Driven Self-Powered Pyroelectric ZnO Integrated Face Mask for Bioprotection.

Rapid spread of infectious diseases is a global threat and has an adverse impact on human health, livelihood, and economic stability, as manifested in the ongoing coronavirus disease 2019 (COVID-19) pandemic. Even though people wear a face mask as protective equipment, direct disinfection of the pathogens is barely feasible, which thereby urges the development of biocidal agents. Meanwhile, repetitive respiration generates temperature variation wherein the heat is regrettably wasted. Herein, a biocidal ZnO nanorod-modified paper (ZNR-paper) composite that is 1) integrated on a face mask, 2) harvests waste breathing-driven thermal energy, 3) facilitates the pyrocatalytic production of reactive oxygen species (ROS), and ultimately 4) exhibits antibacterial and antiviral performance is proposed. Furthermore, in situ generated compressive/tensile strain of the composite by being attached to a curved mask is investigated for high pyroelectricity. The anisotropic ZNR distortion in the bent composite is verified with changes in ZnO bond lengths and OZnO bond angles in a ZnO4 tetrahedron, resulting in an increased polarization state and possibly contributing to the following pyroelectricity. The enhanced pyroelectric behavior is demonstrated by efficient ROS production and notable bioprotection. This study exploring the pre-strain effect on the pyroelectricity of ZNR-paper might provide new insights into the piezo-/pyroelectric material-based applications.

Evaluation of a sterile, filter-based, in-house method for rapid direct bacterial identification and antimicrobial susceptibility testing using positive blood culture.

This study aimed to assess the performance of our in-house method for rapid direct bacterial identification (ID) and antimicrobial susceptibility testing (AST) using a positive blood culture (BC) broth. For Gram-negative bacteria, 4 mL of BC broth was aspirated and passed through a Sartorius Minisart syringe filter with a pore size of 5 µm. The filtrate was then centrifuged and washed. A small volume of the pellet was used for ID, using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and for AST, using automated broth microdilution. For Gram-positive cocci, 4 mL of BC broth was passed through the Minisart syringe filter. Then, 4 mL of sterile distilled water was injected in the direction opposite to that of the filtration to collect the bacterial residue trapped in the filter. Compared with the conventional method performed with pure colonies on agar plates, 94.0% (234/249) were correctly identified using the in-house method, with rates of 91.4% (127/139) and 97.3% (107/110) for Gram-positive and Gram-negative isolates, respectively. Of 234 correctly identified isolates, 230 were assessed by AST. Categorical agreement and essential agreement were 93.3% and 94.5%, respectively, with a minor error rate of 3.8%, a major error rate of 3.4%, and a very major error rate of 1.6%. Our in-house preparation method showed good performance in rapid direct ID and AST using positive BC broths compared to the conventional method. This simple method can shorten the conventional turnaround time for ID and AST by at least 1 day, potentially contributing to better patient management.

HPLC-MS/MS Method Validation for Antifungal Agents in Human Serum in Clinical Application.

BACKGROUND: Therapeutic drug monitoring (TDM) of antifungal drugs is recommended. LC-MS/MS outperforms bioassay and high-performance liquid chromatography (HPLC) for TDM. In this study, we validated TDM for voriconazole, posaconazole, and itraconazole using HPLC-MS/MS with the multiple reaction monitoring (MRM) method. METHODS: For the validation of LC-MS/MS for antifungal TDM, accuracy, precision, linearity, carryover, lower limit of quantitation (LLOQ), ion suppression, and sample stability tests were performed according to the guidelines of the United States Food and Drug Administration (FDA) and the Clinical and Laboratory Standards Institute (CLSI). RESULTS: The LC-MS/MS triazole method showed that all analytes had biases less than 8.9% and coefficients of variation (CV) less than 7.7%. The linearity was validated over the ranges of 0.20 to 5.86 mg/L for voriconazole, 0.12 to 4.96 mg/L for posaconazole, 0.09 to 1.85 mg/L for itraconazole, and 0.12 to 2.38 mg/L for OH-itraconazole. Ion suppression and carryover were negligible. The lower limits of quantitation (LLOQs) for voriconazole, posaconazole, itraconazole, and OH-itraconazole were 0.114 mg/L, 0.206 mg/L, 0.118 mg/L, and 0.065 mg/L, respectively. Voriconazole, posaconazole, itraconazole, and OH-itraconazole can be stored at 4℃ for 4 - 7 days, according to sample stability. Sample preparation took < 15 minutes per batch, and analytical run time was 5 minutes per sample. CONCLUSIONS: We developed and validated a simple, reliable, and quick LC-MS/MS method for triazole antifungal agents TDM suitable for routine hospital practice.

Protective Effects of Lanostane Triterpenoids from Chaga Mushroom in Human Keratinocytes, HaCaT Cells, against Inflammatory and Oxidative Stresses.

Inotodiol, a lanostane-type triterpenoid, and many phytochemicals from Chaga mushrooms have been investigated for various allergic diseases. However, the anti-aging and anti-inflammatory activities of inotodiol under different types of oxidative stress and the impact of inotodiol on collagen and hyaluronan synthesis have not been sufficiently studied. Lanostane triterpenoids-rich concentrate, which contained 10% inotodiol as major (inotodiol concentrate), was prepared from Chaga and compared with pure inotodiol in terms of anti-inflammatory activities on a human keratinocyte cell line, HaCaT cells, under various stimulations such as stimulation with ultraviolet (UV) B or tumor necrosis factor (TNF)-α. In stimulation with TNF-α, interleukin (IL)-1ß, IL-6, and IL-8 genes were significantly repressed by 0.44~4.0 µg/mL of pure inotodiol. UVB irradiation induced the overexpression of pro-inflammatory cytokines, but those genes were significantly suppressed by pure inotodiol or inotodiol concentrate. Moreover, pure inotodiol/inotodiol concentrate could also modulate the synthesis of collagen and hyaluronic acid by controlling COL1A2 and HAS2/3 expression, which implies a crucial role for pure inotodiol/inotodiol concentrate in the prevention of skin aging. These results illuminate the anti-inflammatory and anti-aging effects of pure inotodiol/inotodiol concentrate, and it is highly conceivable that pure inotodiol and inotodiol concentrate could be promising natural bioactive substances to be incorporated in therapeutic and beautifying applications.

One-step immunoassay for the detection of food-poisoning related bacteria using a switching peptide.

A one-step immunoassay was developed for five types of food-poisoning-related bacteria using a switching peptide and antibodies isolated from unimmunized horse serum. The one-step immunoassay involves mixing samples and reagents in a homogeneous solution without any washing steps. In this work, a one-step immunoassay configuration was developed using isolated antibodies labelled with an organic fluorescence quencher and a switching-peptide labelled with a fluorescent dye. The fluorescence-labelled switching-peptide was bound to the antigen-binding site of the isolated antibodies before binding to the bacteria (no fluorescence signal), and the switching-peptide dissociated from the antibodies as soon as they bound to the bacteria (fluorescence signal turns on). By quantifying the generated fluorescence signal, the one-step immunoassay presented here allows microbial detection without any washing step.

A comprehensive transcriptional map of primate brain development.

The transcriptional underpinnings of brain development remain poorly understood, particularly in humans and closely related non-human primates. We describe a high-resolution transcriptional atlas of rhesus monkey (Macaca mulatta) brain development that combines dense temporal sampling of prenatal and postnatal periods with fine anatomical division of cortical and subcortical regions associated with human neuropsychiatric disease. Gene expression changes more rapidly before birth, both in progenitor cells and maturing neurons. Cortical layers and areas acquire adult-like molecular profiles surprisingly late in postnatal development. Disparate cell populations exhibit distinct developmental timing of gene expression, but also unexpected synchrony of processes underlying neural circuit construction including cell projection and adhesion. Candidate risk genes for neurodevelopmental disorders including primary microcephaly, autism spectrum disorder, intellectual disability, and schizophrenia show disease-specific spatiotemporal enrichment within developing neocortex. Human developmental expression trajectories are more similar to monkey than rodent, although approximately 9% of genes show human-specific regulation with evidence for prolonged maturation or neoteny compared to monkey.

Development and Validation of a U-HPLC-MS/MS Method for the Concurrent Measurement of four Immunosuppressants in Whole Blood.

BACKGROUND: This study aimed to develop and validate a U-HPLC-MS/MS method for simultaneous determination of four immunosuppressants in human whole blood. METHODS: The method was based on the injection of 20 µL of calibrators and controls pretreated with the liquid phase extraction method for chromatography separation and mass spectrometry determination. LPE offline was performed by adding 0.1 mol/L ZnSO4 and acetonitrile, while separation of target compounds was achieved within 2.5 minutes by a Zorbax Eclipse XDB-C8 column using ammonium acetate and ACN mixed with formic acid as solvents. RESULTS: The assay offers ng/mL detection limits (from 1.1 to 12.4 ng/mL), accuracy (% deviation from -4.4% to 5.6%), precision (CV less than 15% at all QC levels), and linearity (from 23.4 to 948 ng/mL for CsA, from 2.11 to 45.5 ng/mL for TAC, SIR and EVR). The recovery and matrix results were acceptable, and the carryover was less than 1%. The results of method comparison show that IA-based methods overestimated the concentration of drugs compared with the MS-based method. Comparing our MS-based method with external LC-MS/MS showed that the results were within 2 SDs. CONCLUSIONS: We have developed a reliable assay for the analysis of CsA, TAC, SIR and EVR in whole blood using U-HPLC-MS/MS.

Detection of Plasmodium vivax using Automated Hematology Analyzer in the Korean Army.

BACKGROUND: This study aimed to evaluate whether our equation model developed from the Sysmex hematology analyzer can discriminate patients with Plasmodium vivax (P. vivax) infection from those with acute febrile illness (AFI) and healthy controls. Besides, we compared our model with the previously studied models. METHODS: A total of 312 blood samples were collected from the P. vivax, AFI, and healthy control groups. All samples were tested for routine complete blood count conducted by using a Sysmex XE-2100 or XE-5000 analyzer. We compared the reportable and research parameters generated from the Sysmex analyzer among the three groups. The selected parameters that showed a significant difference between the P. vivax and the other group were included in the logistic regression analysis to develop our model (N-OIpv model). Moreover, we analyzed the CBC data according to the previous models, such as the presence of abnormal blue coded events in the WBC/BASO scattergram called the observer-interpretation (OIpv) model, and the previous equation model (N-OD1pv model) developed by Campuzano-Zuluaga et al. Results: The N-OIpv model, which consists of three parameters, such as mean cell volume, plateletcrit, and Lymph-X, showed the best performance for detection of malaria (97.4% accuracy). Also, this model can increase the sensitivity by about 11.9% to 18.1% compared with the OIpv and N-OD1pv models, respectively. CONCLUSIONS: We concluded that the N-OIpv model using the Sysmex hematology analyzer is a useful diagnostic tool in the routine laboratory workup for malaria.

Evaluation of Toxicity and Efficacy of Inotodiol as an Anti-Inflammatory Agent Using Animal Model.

Chaga mushroom (Inonotus obliquus) comprises polyphenolic compounds, triterpenoids, polysaccharides, and sterols. Among the triterpenoid components, inotodiol has been broadly examined because of its various biological activities. The purpose of this study is to examine inotodiol from a safety point of view and to present the potential possibilities of inotodiol for medical usage. From chaga mushroom extract, crude inotodiol (INO20) and pure inotodiol (INO95) were produced. Mice were treated with either INO20 or INO95 once daily using oral administration for repeated dose toxicity evaluation. Serum biochemistry parameters were analyzed, and the level of pro-inflammatory cytokines in the serum was quantified. In parallel, the effect of inotodiol on food allergic symptoms was investigated. Repeated administration of inotodiol did not show any mortality or abnormalities in organs. In food allergy studies, the symptoms of diarrhea were ameliorated by administration with INO95 and INO20. Furthermore, the level of MCPT-1 decreased by treatment with inotodiol. In this study, we demonstrated for the first time that inotodiol does not cause any detrimental effect by showing anti-allergic activities in vivo by inhibiting mast cell function. Our data highlight the potential to use inotodiol as an immune modulator for diseases related to inflammation.

Management of XEN Gel Stent Exposure with Conjunctival Erosion via Rotational Conjunctival Flap and Amniotic Membrane Transplantation-A Case Report.

Background: Despite its proven effectiveness and safety profile, the XEN gel stent (Allergan Inc., CA, USA) for minimally invasive glaucoma surgery (MIGS) has a probability of postoperative complications, including postoperative hypotony, hyphema, stent migration, stent obstruction, bleb fibrosis, and fibrin formation. In particular, the use of adjunctive Mitomycin-C (MMC) might be associated with bleb-related complications, including conjunctival erosion, XEN gel stent exposure, and blebitis. However, there are few studies on XEN gel stent exposure and its management. We describe a case of XEN gel stent exposure with conjunctival erosion 18 months postoperatively, which resolved effectively after combination treatment with a rotational conjunctival flap and amniotic membrane transplantation. Case presentation: A 74-year-old Korean male patient with diabetes and hypertension underwent uncomplicated ab interno XEN gel stent implantation with a subconjunctival injection of 0.1 cc of 0.02% MMC and presented with low intraocular pressure (IOP) with a well-functioning filtering bleb. Periocular pain and tearing developed 18 months after the initial operation, with mild deterioration of visual acuity to 20/100. Despite conservative medical treatment, the conjunctival erosion was not relieved. Anterior segment optical coherence tomography (AS-OCT) revealed an exposed XEN gel stent with conjunctival erosion. We performed bleb revision surgery using a rotational conjunctival flap and amniotic membrane transplantation. Slit-lamp examination and AS-OCT showed a well-formed moderate bleb without leakage, and IOP continued to be well controlled (14 mm Hg with latanoprost) until six months after bleb revision. Conclusions: This case report highlights the importance of careful examination, including slit-lamp examination, the Seidel test, and AS-OCT, to identify accurate anatomical positioning and to monitor ocular surface changes after XEN gel stent implantation with MMC or 5-FU. Combination treatment (rotational conjunctival flap and amniotic membrane transplantation) may be relatively safe for persistent XEN gel stent exposure.

Application of a multiplex immunochromatographic assay for rapid identification of carbapenemases in a clinical microbiology laboratory: performance and turn-around-time evaluation of NG-test Carba 5.

BACKGROUND: Prompt and accurate identification of carbapenemase production is essential for appropriate treatment and infection control. NG-Test Carba 5 (termed herein "Carba 5"; NG Biotech, Guipry, France) is a multiplex immunochromatographic assay for the rapid phenotypic identification of five major carbapenemases (KPC, NDM, VIM, IMP, and OXA-48-like) from bacterial isolates. This study aimed to evaluate the diagnostic performance of Carba 5 and its impact on the turn-around-time in a clinical microbiology laboratory. RESULTS: Carba 5 was retrospectively evaluated using 78 carbapenemase producers and 23 non-carbapenemase producers confirmed by PCR and sequencing. The performance and time required for carbapenemase identification were prospectively evaluated using 47 carbapenem resistant Enterobacteriaceae isolates, and the results were compared to those obtained using Xpert Carba-R (Cepheid, Sunnyvale, CA, USA). For the bacterial isolates included in retrospective and prospective evaluation, the Carba 5 assay correctly identified 147 isolates except one isolate with a sensitivity of 99.13% (95% CI 95.25-99.98%) and specificity of 100% (95% CI 89.42-100%). The Carba 5 assay missed one VIM-1 among 13 VIM producers. The assay showed a sensitivity of 92.31% (95% CI 63.97-99.81%) for detecting VIM and 100% for detecting KPC, NDM, OXA-48-like, and IMP. Compared to the Xpert Carba-R assay, Carba 5 exhibited 100% agreement and was more time-efficient (median time 24 min vs. 1 h 11 min). CONCLUSIONS: The Carba 5 assay has potential as an alternative to molecular methods for detecting major carbapenemases from bacterial isolates in a clinical microbiology laboratory. Compared to the Xpert Carba-R, Carba 5 turns out to be more affordable and time-efficient while showing a comparable performance, and may accelerate therapeutic and infection control decisions.

Quantitative visual tests in primary open-angle glaucoma patients according to three different lights with different color-rendering index.

PURPOSE: To compare quantitative visual tests, such as visual acuity, contrast sensitivity, and color vision tests in patients with primary open-angle glaucoma (POAG) patients according to three different light systems with different color-rendering index (CRI). METHODS: This was a cross-sectional study of 36 eyes in 36 patients with POAG. Three different light systems consisting of a 3-band fluorescent lamp (CRI 80), a white LED (CRI 75), and a quantum dot LED (CRI > 95) were used. All lights had the same illuminance of 230 lx to exclude illuminance effects. The visual testing included best-corrected visual acuity (BCVA) using an ETDRS chart, a CSV-1000E contrast test, and a color test performed by the Farnsworth Munsell 100-hue test. RESULTS: There was no significant difference in BCVA (p = 0.86). There were no significant differences in the detail contrast tests according to the three light systems (p = 0.95, p = 0.94, p = 0.94, respectively, p = 0.64). There was significant difference between the three light systems in color test (p = 0.042). The color test scores with a quantum dot LED were significantly lower than those of the white LED and 3-band fluorescent lamp (p = 0.03 and 0.047, respectively). CONCLUSIONS: POAG patients did not show significant differences in visual acuity scores and contrast test scores, expressed as black and white symbols, according to the different light systems. However, POAG patients tested under a quantum dot LED (CRI > 95) could distinguish color differences better than in the other light systems.

Efficacy of interspinous device on adjacent segment degeneration after single level posterior lumbar interbody fusion: a minimum 2-year follow-up.

OBJECTIVE: Adjacent segment degeneration (ASD) is a well-known problem of posterior lumbar interbody fusion (PLIF). A device for interspinous assisted motion (DIAM) has been recently applied at the adjacent segment to pedicle screw instrumentation to create a dynamic transition zone. The aim of this study was to determine whether DIAM implantation at the adjacent segment could reduce the occurrence of radiologic and symptomatic ASD. METHODS: This retrospective study reviewed 51 patients who underwent PLIF with or without DIAM between 2005 and 2016. They were followed up for more than 24 months. The mean follow-up was over 5 years. Fourteen patients underwent PLIF with DIAM implantation at the cephalad level (Group A) and 37 patients received PLIF only (Group B). In radiologic ASD, several parameters were measured using pre- and post-operative radiographs and magnetic resonance image for lumbar degenerative disease and paraspinal muscle. Visual analogue scale (VAS) and Roland-Morris Disability Questionnaire (RMDQ) scores of back and leg were used to investigate symptomatic ASD. RESULTS: In postoperative radiographic changes, disc height narrowing and progression of spondylolisthesis at adjacent segment were significantly less in group A than those in group B (0.58 mm versus 1.17 mm, p = 0.038 and 0.30 mm versus 1.69 mm, p = 0.041, respectively). In clinical assessments, back VAS and RMDQ scores improved significantly more in group A (-4.07 versus -2.54, p = 0.029 and -7.57 versus -5.43, p = 0.016, respectively). CONCLUSION: DIAM implantation with single-level PLIF could prevent disc height narrowing and progression of spondylolisthesis at adjacent segment. Clinically, DIAM implantation reduced back pain and disability. Therefore, DIAM implantation could help slow the progression of both radiologic and symptomatic ASD.

Muscle stem cell isolation and in vitro culture for meat production: A methodological review.

Cultured muscle tissue-based protein products, also known as cultured meat, are produced through in vitro myogenesis involving muscle stem cell culture and differentiation, and mature muscle cell processing for flavor and texture. This review focuses on the in vitro myogenesis for cultured meat production. The muscle stem cell-based in vitro muscle tissue production consists of a sequential process: (1) muscle sampling for stem cell collection, (2) muscle tissue dissociation and muscle stem cell isolation, (3) primary cell culture, (4) upscaled cell culture, (5) muscle differentiation and maturation, and (6) muscle tissue harvest. Although muscle stem cell research is a well-established field, the majority of these steps remain to be underoptimized to enable the in vitro creation of edible muscle-derived meat products. The profound understanding of the process would help not only cultured meat production but also business sectors that have been seeking new biomaterials for the food industry. In this review, we discuss comprehensively and in detail each step of cutting-edge methods for cultured meat production. This would be meaningful for both academia and industry to prepare for the new era of cellular agriculture.

Transcriptional landscape of the prenatal human brain.

The anatomical and functional architecture of the human brain is mainly determined by prenatal transcriptional processes. We describe an anatomically comprehensive atlas of the mid-gestational human brain, including de novo reference atlases, in situ hybridization, ultra-high-resolution magnetic resonance imaging (MRI) and microarray analysis on highly discrete laser-microdissected brain regions. In developing cerebral cortex, transcriptional differences are found between different proliferative and post-mitotic layers, wherein laminar signatures reflect cellular composition and developmental processes. Cytoarchitectural differences between human and mouse have molecular correlates, including species differences in gene expression in subplate, although surprisingly we find minimal differences between the inner and outer subventricular zones even though the outer zone is expanded in humans. Both germinal and post-mitotic cortical layers exhibit fronto-temporal gradients, with particular enrichment in the frontal lobe. Finally, many neurodevelopmental disorder and human-evolution-related genes show patterned expression, potentially underlying unique features of human cortical formation. These data provide a rich, freely-accessible resource for understanding human brain development.

Analytical Performance of Two Enzymatic Methods for Glycated Albumin.

BACKGROUND: The measurement of glycemic control among patients with diabetes mellitus is important for predicting the risk of diabetic complications. Glycated hemoglobin (HbA1c) measurements have been used for long-term glycemic control in clinical practice. However, glycated albumin (GA) or glycated serum protein (GSP) is a more reliable indicator of glycemic control in the short term (2 - 4 weeks) and an alternative marker of HbA1c in clinical situations with changing red blood cell (RBC) lifespan. Here, we evaluated an analytical performance of the two enzymatic assays commercially available, Lucica GA-L and Autolab GA, for the determination of GA (%). METHODS: For each assay, the imprecision was evaluated based on CLSI EP05-A2. In total, serum samples of 283 subjects were simultaneously tested using the two enzymatic assays for method comparison according to CLSI EP09-A3. Some subjects collected the laboratory data for HbA1c. RESULTS: The GA (%) value of the Lucica GA-L assay showed highly reproducible results with within-run, between-run, and total coefficient of variations (CVs) below 2.4%. The Autolab GA assay also showed reliable results with within-run, between-run, and total CVs below 3.9%. The Lucica GA-L assay showed a very high correlation with the Autolab GA assay (r = 0.9993). However, at the median decision point (MDP, 14.3%), the estimated bias of the Autolab GA assay was 4.5%, exceeding the allowable bias (2.9%) accounting for the biological variation. For the correlation analysis between HbA1c and GA (%), the two assays demonstrated the same pattern, with no statistical differences between the two independent correlation coefficients. CONCLUSIONS: Both GA assays evaluated in this study showed good precision and excellent correlation, but the comparability at MDP did not meet the acceptance criteria.

Characteristics of Klebsiella pneumoniae Isolates from Stool Samples of Patients with Liver Abscess Caused by Hypervirulent K. pneumoniae.

BACKGROUND: Hypervirulent Klebsiella pneumoniae (hvKP) has been the most significant pathogen for liver abscesses in East Asia including the Republic of Korea (ROK). Although gastrointestinal colonization of K. pneumoniae may cross the intestinal barrier to invade the liver, characteristics of gastrointestinal carriage K. pneumoniae of hvKP liver abscess patients in the ROK are not well known. METHODS: Characteristics of K. pneumoniae isolated from stool samples and liver aspirate samples of patients with hvKP liver abscess at a tertiary care hospital in the ROK between 2017 and 2018 were evaluated. RESULTS: Out of 37 patients with hvKP liver abscess, 11 patients were noted to have K. pneumoniae isolated from stool samples and were enrolled for analysis. The median age was 71 years. For hvKP isolates from the liver aspirate samples, the most common serotype was K1 (72.7%) followed by K2 (27.3%). For K. pneumoniae isolates from the stool sample, the majority was non-K1/K2 serotype (72.7%). Among non-K1/K2 serotype isolates, high variability of sequence type (ST; ST15, ST307, ST37, ST273, ST2622, and ST42) with high rate of presence of extended-spectrum beta-lactamase (100.0%) was noted. The concordance rate of the K. pneumoniae isolates between the liver aspirate samples and the stool samples from the primary hvKP liver abscess was low (27.3%). CONCLUSION: This study suggests that significant heterogeneity of K. pneumoniae colonizing intestinal tract of the hvKP liver abscess patients. Further studies involving a larger number of hvKP liver abscess patients with continuing surveillance are needed to define the changing epidemiology and the role of gastrointestinal K. pneumoniae in the hvKP liver abscess patients in the ROK.

An optimal cortical bone trajectory technique to prevent early surgical complications.

BACKGROUND: Cortical bone trajectory (CBT) technique has a theoretical benefit for patients with osteoporosis, and leads to reduce screw loosening. However, there are no reports of complications and outcomes of CBT. METHODS: Consecutive patients (n = 34) with degenerative lumbar spines who underwent PLIF between December 2013 and December 2015 and were followed up for at least six months were analyzed in this study. Bone mineral density, fusion rate, cage subsidence, C-arm, screw loosening, screw violation, trajectory angle of the screw, Hounsfield unit and extent of facetectomy were examined. Outcome assessments were obtained in all patients preoperatively and postoperatively. RESULTS: There were 34 patients and 73 screw levels. After the surgery with cortical screw fixation and PLIF, patients had good clinical outcomes. However, ten of the 34 patients had problems with cortical screw fixation such as screw loosening or cage migration. In the patients with screw loosening, two underwent revision surgery due to cage migration, and one had an infection. Incorrect trajectory angles of the screw were significantly related with screw loosening. Low BMD and HU at screw fixation level were associated with screw loosening. Cage subsidence was statistically related with clinical outcomes. CONCLUSION: The cortical screw offers improved clinical outcomes since it requires minimal muscle dissection. However, we have experienced some early complications using this technique. To reduce complications such as screw loosening, an exact insertion angle of the screw and osteoporotic bone quality should be considered carefully.