Cronobacter Species in Powdered Infant Formula and Their Detection Methods

Xinjie Song,Hui Teng,Lei Chen,Myunghee Kim 한국축산식품학회 2018 한국축산식품학회지 Vol.38 No.2

Cronobacter species have been associated with disease outbreaks and sporadic infections, particularly in premature and immunocompromised infants. Cronobacter species can cause foodborne infections such as neonatal meningitis, septicaemia and necrotising enterocolitis. Accordingly, there is an urgent need to control and monitor the Cronobacter speciesin food, especially in powdered infant formula (PIF) and other baby foods. Therefore, in this review, the isolation and prevalence of Cronobacter species in infant food including PIF and the recent advance of detection methods are discussed for the better understanding on the current research status of Cronobacter species.

Modified exosomal SIRPα variants alleviate white matter injury after intracerebral hemorrhage via microglia/macrophages

Xinjie Gao,Heng Yang,Weiping Xiao,Jiabin Su,Yuwen Zhang,He Wang,Wei Ni,Yuxiang Gu 한국생체재료학회 2022 생체재료학회지 Vol.26 No.4

Background: Despite limited efficiency, modulation of microglia/macrophages has shown to attenuate neuroinflammation after intracerebral hemorrhage (ICH). In this context, we evaluated the efficacy of modified exosomal signal regulatory protein α (SIRPα) variants (SIRPα-v Exos) in microglia/macrophages and neuroinflammation-associated white matter injury after ICH. Methods: SIRPα-v Exos were engineered to block CD47-SIRPα interactions. After obtaining SIRPα-v Exos from lentivirus-infected mesenchymal stem cells, C57BL/6 mice suffering from ICH underwent consecutive intravenous injections of SIRPα-v Exos (6 mg/kg) for 14 days. Afterwards, the volume of hematoma and neurological dysfunctions were assessed in mice continuously until 35 days after ICH. In addition, demyelination, electrophysiology and neuroinflammation were evaluated. Furthermore, the mechanisms of microglial regulation by SIRPα-v Exos were investigated in vitro under coculture conditions. Results: The results demonstrated that the clearance of hematoma in mice suffering from ICH was accelerated after SIRPα-v Exo treatment. SIRPα-v Exos improved long-term neurological dysfunction by ameliorating white matter injury. In addition, SIRPα-v Exos recruited regulatory T cells (Tregs) to promote M2 polarization of microglia/macrophages in the peri-hematoma tissue. In vitro experiments further showed that SIRPα-v Exos regulated primary microglia in a direct and indirect manner in synergy with Tregs. Conclusion: Our studies revealed that SIRPα-v Exos could accelerate the clearance of hematoma and ameliorate secondary white matter injury after ICH through regulation of microglia/macrophages. SIRPα-v Exos may become a promising treatment for ICH in clinical practice.

Introduction to Evolutionary Algorithms

Xinjie Yu,Mitsuo Gen 대한산업공학회 2010 Industrial Engineeering & Management Systems Vol.9 No.4

Immunochromatographic Strip Assay for Detection of Cronobacter sakazakii in Pure Culture

( Xinjie Song ),( Shruti Shukla ),( Gibaek Lee ),( Myunghee Kim ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.11

Cronobacter sakazakii (C. sakazakii) is a foodborne pathogen, posing a high risk of disease to infants and immunocompromised individuals. In order to develop a quick, easy, and sensitive assay for detecting C. sakazakii, a rabbit anti-C. sakazakii immunoglobulin G (IgG) was developed using sonicated cell protein from C. sakazakii. The developed anti-C. sakazakii (IgG) was of good quality and purity, as well as species-specific. The developed rabbit anti-C. sakazakii IgG was attached to the surface of a sulforhodamine B-encapsulated liposome to form an immunoliposome. A test strip was then prepared by coating goat anti-rabbit IgG onto the control line and rabbit anti-C. sakazakii IgG onto the test line, respectively, of a plastic-backed nitrocellulose membrane. A purple color signal both on the test line and the control line indicated the presence of C. sakazakii in the sample, whereas purple color only on the control line indicated the absence of C. sakazakii in the sample. This immunochromatographic strip assay could produce results in 15 min with a limit of detection of 107 CFU/ml in C. sakazakii culture. The immunochromatographic strip assay also showed very good specificity without cross-reactivity with other tested Cronobacter species. Based on these results, the developed immunochromatographic strip assay is efficient for the detection of C. sakazakii and has high potential for on-site detection.

Indirect Noncompetitive Enzyme Linked Immunosorbent Assay for Cronobacter muytjensii

Xinjie Song,Hyerim Leem,Shruti Shukla,Sunhyun Park,Myunghee Kim 한국식품영양과학회 2011 한국식품영양과학회 학술대회발표집 Vol.2011 No.10

Development of antibodies and immunoassay against Cronobacter spp.

Xinjie Song,Shruti Shukla,Gibaek Lee,Myunghee Kim 한국식품영양과학회 2014 한국식품영양과학회 학술대회발표집 Vol.2014 No.10

Comparison of Observation Confidence Estimators for Robust Speaker Verification

Xinjie Ma,Tan Dat Trinh,Jin Young Kim 한국정보기술학회 2017 한국정보기술학회논문지 Vol.15 No.7

In this paper, we first explore a modified adaptive Gaussian mixture model (MAGMM) by investigating the confidence value of observation vectors to deal with noise conditions problem. The observation confidence values are estimated by using the frame SNR values calculated between the input noisy speech and the enhanced speech, and the sigmoid function. We compare three speech enhancement techniques, minimum mean square error logarithm shorttime spectral amplitude (MMSE log-STSA), low-rank matrix recovery (LRR) and multiple low-rank representation (MLRR), for observation confidence computation. Furthermore, we also consider the effect of the use of observation confidence value in the GMM-supervector (GSV) and i-vector approaches which are considers as input feature vectors for the Support vector machine (SVM). To verify the accuracy of the speaker system, we use utterances from a Korean drama “You came from the stars.” The experimental results show that our proposed approaches achieve better performance than the baseline systems under noisy environments.

Mediating Role of Viral Anxiety and Insomnia in Relationship Between Work-Related Stress and Depression Among Cold Chain Workers During COVID-19 Pandemic

Xinjie Du,Runlian He,Ahmed Oli,Cho Eulah,Chung Seockhoon 대한의학회 2023 Journal of Korean medical science Vol.38 No.43

Background: Here we investigated whether cold chain workers’ insomnia, work-related stress, and viral anxiety contributed to their depression. Furthermore, we investigated the role of viral anxiety in mediating the association between work-related stress and depressive symptoms. Methods: All 200 invited cold chain workers voluntarily responded to an online survey. All were working at a market in Taiyuan, Shanxi Province, China, and responsible for testing nucleic acids in imported cold chain foods and disinfecting outer packaging at government request. We collected their demographic variables and rated their symptoms using the Stress and Anxiety to Viral Epidemics-6 Items (SAVE-6), Patient Health Questionnaire-9, Insomnia Severity Index (ISI), Perceived Stress Scale (PSS), and Maslach Burnout Inventory - General Survey (MBI-GS). Results: Cold chain workers’ depression was significantly correlated with higher SAVE-6 (r = 0.450, P < 0.01), ISI (r = 0.603, P < 0.01), MBI-GS (r = 0.481, P < 0.01), and PSS (r = 0.390, P < 0.01) scores. SAVE-6 score was significantly correlated with ISI (r = 0.462, P < 0.01), MBI-GS (r = 0.305, P < 0.01), and PSS (r = 0.268, P < 0.01) scores. Linear regression revealed that their depression was predicted by SAVE-6 (β = 0.183, P = 0.003), ISI (β = 0.409, P < 0.001), and MBI-GS (β = 0.236, P = 0.002, adjusted R2 = 0.440, F = 40.04, P < 0.001) scores. Mediation analysis showed that their burnout directly influenced their depression, while viral anxiety or insomnia severity mediated the influence of burnout on depression. Conclusion: The study showed that burnout was a direct cause of depression and that viral anxiety and insomnia severity mediated the relationship between burnout and depression.

Introduction to Evolutionary Algorithms

Yu, Xinjie,Gen, Mitsuo Korean Institute of Industrial Engineers 2010 Industrial Engineeering & Management Systems Vol.9 No.4

Detection of <i>Cronobacter</i> species in powdered infant formula using immunoliposome-based immunomagnetic concentration and separation assay

Song, Xinjie,Shukla, Shruti,Kim, Myunghee Elsevier 2018 FOOD MICROBIOLOGY Vol.72 No.-

<P><B>Abstract</B></P> <P> <I>Cronobacter</I> species are foodborne pathogens that can affect the human central nervous system. Survivors of <I>Cronobacter</I> infections often suffer from severe neurological impairments, including hydrocephalus, quadriplegia, and developmental delays in all ages, especially in infants and the immunocompromised. Moreover, <I>Cronobacter</I> species pose a high risk in powdered infant formula (PIF) because PIF is a major source of nutrition for infants worldwide. To develop a rapid and sensitive detection method for <I>Cronobacter</I> species in PIF, immunoliposomes and immunomagnetic nanoparticles were synthesized, after which an immunoliposome-based immunomagnetic concentration and separation assay was developed and applied to PIF for the detection of <I>Cronobacter</I> species. The detection limits of the developed assay were 5.9 × 10<SUP>3</SUP> ± 0.7–4.8 × 10<SUP>4</SUP> ± 0.2 CFU/mL for <I>Cronobacter</I> species in pure culture with no cross-reactivity with 13 other tested non-<I>Cronobacter</I> strains. Additionally, the developed assay could provide results in 3 h when the contaminated level was higher than 10<SUP>4</SUP> CFU/25 g PIF and in 9 h when the contaminated level was 10 CFU/25 g PIF. The developed immunoliposome-based immunomagnetic concentration and separation assay is rapid, sensitive, and simple and thus has great potential for use in the detection of <I>Cronobacter</I> species in PIF.</P> <P><B>Highlights</B></P> <P> <UL> <LI> An an immunoliposome and an immnomagnetic nanoparticle were synthesized with anti-<I>Cronobacter</I> IgG. </LI> <LI> The developed assay can provide results in 3 h and 9 h with high and low contaminated level of <I>Cronobacter</I>species. </LI> <LI> The developed assay is efficient for the detection of <I>Cronobacter</I> species in powdered infant formula. </LI> </UL> </P>