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1.
Front Microbiol ; 15: 1374568, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38618485

RESUMO

CrAssphages are human gut bacteriophages with potential use as an indicator of human fecal contamination in water and other environmental systems. We determined the prevalence and abundance of crAssphages in water, food, and fecal samples and compared these estimates with the prevalence of norovirus. Samples were tested using two crAssphage-specific qPCR assays (CPQ056 and TN201-203) and for norovirus using TaqMan realtime RT-PCR. CrAssphage was detected in 40% of human fecal specimens, 61% of irrigation water samples, 58.5% of stream water samples, and 68.5% of fresh leafy greens samples. Interestingly, across all sample categories, crAssphage concentrations were 2-3 log10 higher than norovirus concentrations. The correlation of detection of crAssphage and norovirus was significant for the irrigation water samples (r = 0.74, p = 7.4e-06). Sequences obtained from crAssphage positive samples from human fecal and stream water samples phylogenetically clustered with genotype I crAssphages, whereas sequences derived from irrigation water samples clustered differently from other genotypes. Our data show that crAssphages were prevalent in norovirus-positive water samples and in fresh leafy green samples, there was a strong correlation between the presence of crAssphage and norovirus. CrAssphage genomic copies were consistently higher than norovirus copies in all sample types. Overall, our findings suggest that crAssphages could be used as reliable indicators to monitor fecal-borne virus contamination within the food safety chain.

2.
Adv Mater ; : e2312747, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38531112

RESUMO

Herein, a high-quality gate stack (native HfO2 formed on 2D HfSe2) fabricated via plasma oxidation is reported, realizing an atomically sharp interface with a suppressed interface trap density (Dit ≈ 5 × 1010 cm-2 eV-1). The chemically converted HfO2 exhibits dielectric constant, κ ≈ 23, resulting in low gate leakage current (≈10-3 A cm-2) at equivalent oxide thickness ≈0.5 nm. Density functional calculations indicate that the atomistic mechanism for achieving a high-quality interface is the possibility of O atoms replacing the Se atoms of the interfacial HfSe2 layer without a substitution energy barrier, allowing layer-by-layer oxidation to proceed. The field-effect-transistor-fabricated HfO2/HfSe2 gate stack demonstrates an almost ideal subthreshold slope (SS) of ≈61 mV dec-1 (over four orders of IDS) at room temperature (300 K), along with a high Ion/Ioff ratio of ≈108 and a small hysteresis of ≈10 mV. Furthermore, by utilizing a device architecture with separately controlled HfO2/HfSe2 gate stack and channel structures, an impact ionization field-effect transistor is fabricated that exhibits n-type steep-switching characteristics with a SS value of 3.43 mV dec-1 at room temperature, overcoming the Boltzmann limit. These results provide a significant step toward the realization of post-Si semiconducting devices for future energy-efficient data-centric computing electronics.

3.
Int J Mol Sci ; 25(3)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38338858

RESUMO

Bisphenol is a chemical substance widely used in plastic products and food containers. In this study, we observed a relationship between DNA methylation and atopic dermatitis (AD) in the peripheral blood mononuclear cells (PBMCs) of pregnant women exposed to bisphenol A (BPA) and its alternatives, bisphenol S (BPS) and bisphenol F (BPF). DNA methylation is an epigenetic mechanism that regulates gene expression, which can be altered by environmental factors, and affects the onset and progression of diseases. We found that genes belonging to the JAK-STAT and PI3K-AKT signaling pathways were hypomethylated in the blood of pregnant women exposed to bisphenols. These genes play important roles in skin barrier function and immune responses, and may influence AD. Therefore, we suggest that not only BPA, but also BPS and BPF, which are used as alternatives, can have a negative impact on AD through epigenetic mechanisms.


Assuntos
Dermatite Atópica , Fenóis , Gestantes , Humanos , Feminino , Gravidez , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/genética , Fosfatidilinositol 3-Quinases , Leucócitos Mononucleares , Metilação de DNA , Compostos Benzidrílicos/toxicidade , Epigênese Genética
4.
In Vitro Cell Dev Biol Anim ; 60(2): 195-208, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228999

RESUMO

Eunkyo-san is widely used in the treatment of severe respiratory infections. Mast cells not only serve as host cells for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but also they also exacerbate Coronavirus disease in 2019 (COVID-19) by causing a cytokine storm. Here we investigated whether Eunkyo-san and its active compound naringenin regulate the expression of inflammatory cytokines and factors connected to viral infection in activated human mast cell line, HMC-1 cells. Eunkyo-san and naringenin significantly reduced levels of inflammatory cytokines including interleukin (IL)-1ß, IL-6, IL-8, thymic stromal lymphopoietin, and tumor necrosis factor-α without impacting cytotoxicity. Eunkyo-san and naringenin reduced levels of factors connected to SARS-CoV-2 infection such as angiotensin-converting enzyme 2 (ACE2, SARS-CoV-2 receptor), transmembrane protease/serine subfamily member 2, and tryptase in activated HMC-1 cells. Treatment with Eunkyo-san and naringenin considerably reduced expression levels of ACE2 transcription factor, AP-1 (C-JUN and C-FOS) by blocking phosphatidylinositide-3-kinase and c-Jun NH2-terminal kinases signaling pathways. In addition, Eunkyo-san and naringenin effectively suppressed activation of signal transducer and activator of transcription 3, nuclear translocation of nuclear factor-κB, and activation of caspase-1 in activated HMC-1 cells. Furthermore, Eunkyo-san and naringenin reduced expression of ACE2 mRNA in two activated mast cell lines, RBL-2H3 and IC-2 cells. The overall study findings showed that Eunkyo-san diminished the expression levels of inflammatory cytokines and ACE2, and these findings imply that Eunkyo-san is able to effectively mitigating the cytokine storm brought on by SARS-CoV-2 infection.


Assuntos
COVID-19 , Citocinas , Humanos , Animais , Citocinas/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/farmacologia , Síndrome da Liberação de Citocina/metabolismo , Mastócitos , SARS-CoV-2
5.
J Korean Neurosurg Soc ; 67(1): 73-83, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37454676

RESUMO

OBJECTIVE: The Act on Life-Sustaining Treatment (LST) decisions for end-of-life patients has been effective since February 2018. An increasing number of patients and their families want to withhold or withdraw from LST when medical futility is expected. This study aimed to investigate the status of the Act on LST decisions for patients with acute cerebrovascular disease at a single hospital. METHODS: Between January 2017 and December 2021, 227 patients with acute cerebrovascular diseases, including hemorrhagic stroke (n=184) and ischemic stroke (n=43), died at the hospital. The study period was divided into the periods before and after the Act. RESULTS: The duration of hospitalization decreased after the Act was implemented compared to before (15.9±16.1 vs. 11.2±18.6 days, p=0.127). The rate of obtaining consent for the LST plan tended to increase after the Act (139/183 [76.0%] vs. 27/44 [61.4%], p=0.077). Notably, none of the patients made an LST decision independently. Ventilator withdrawal was more frequently performed after the Act than before (52/183 [28.4%] vs. 0/44 [0%], p<0.001). Conversely, the rate of organ donation decreased after the Act was implemented (5/183 [2.7%] vs. 6/44 [13.6%], p=0.008). Refusal to undergo surgery was more common after the Act was implemented than before (87/149 [58.4%] vs. 15/41 [36.6%], p=0.021) among the 190 patients who required surgery. CONCLUSION: After the Act on LST decisions was implemented, the rate of LST withdrawal increased in patients with acute cerebrovascular disease. However, the decision to withdraw LST was made by the patient's family rather than the patient themselves. After the execution of the Act, we also observed an increased rate of refusal to undergo surgery and a decreased rate of organ donation. The Act on LST decisions may reduce unnecessary treatments that prolong end-of-life processes without a curative effect. However, the widespread application of this law may also reduce beneficial treatments and contribute to a decline in organ donation.

6.
Heliyon ; 9(12): e23028, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38149210

RESUMO

Enteroviruses (EVs), which belong to the Picornaviridae family, infect individuals asymptomatically or cause mild symptoms (fever, runny nose, cough, skin rash, sneezing, mouth blister). Severe cases can cause various diseases, such as acute hemorrhagic conjunctivitis, aseptic meningitis, or myocarditis, especially in infants. These viruses can be transmitted via the fecal-oral route via contaminated water. In this study, we established a polymerase chain reaction (PCR) method for detecting EVs in water sample using Coxsackievirus B5 (CV-B5) and Echovirus 30 (E-30), which belong to species B of the four species of EVs (EV-A to D). Several methods have been investigated and compared for the detection of EVs, including real-time reverse transcription (RT) polymerase chain reaction and conventional RT-PCR. The most sensitive primer sets were selected, and the PCR conditions were modified to increase sensitivity. We also quantified the detection limits of real-time and conventional RT-PCR. The detection limits of conventional RT-PCR were detected in 105-106 copy/mL for CV-B5 and 106-107 copy/mL for E-30, respectively. This optimized method for detecting EVs is expected to contribute substantially to the investigation of EV outbreaks in water samples.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38033204

RESUMO

Optimizing the contact structure while reducing the contact resistance in advanced transistors has become an extremely challenging problem. Because the existing techniques are limited to controlling only one semiconductor type, either n- or p-type, owing to their work function differences, significant challenges are encountered in the integration of a contact structure and metal suitable for both n- and p-type semiconductors. This is a formidable drawback of the complementary metal-oxide-semiconductor (CMOS) technology. In this paper, we demonstrate the effectiveness of a metal/graphene/semiconductor (MGrS) as a universal source/drain contact structure for both n- and p-type transistors. The MGrS contact structure significantly enhanced the reverse current density (JR) and reduced the Schottky barrier height (SBH) for both semiconductor types. From the analysis of the SBH values and their relationship with the metal work function, which refers to the S-parameter, the van der Waals contact of graphene (Gr) effectively alleviated the Fermi level (FL) pinning for both semiconductor types, reducing the metal-induced gap states (MIGS) at the Gr/semiconductor interface. Furthermore, Gr effectively modulated the work function of the contact metal to yield a position favorable for each semiconductor type. Consequently, a single MGrS contact structure on a Si substrate resulted in excellent Ohmic contacts in both n- and p-type Si, with SBH values reduced to 0.012 and 0.024 eV for n- and p-type Si, respectively. This new approach for integrating the contact structures of semiconductor types will lead to extended capabilities for high-performance device applications and CMOS logical circuitry.

8.
J Clin Med ; 12(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37834759

RESUMO

BACKGROUND: Vascular conditions can affect the recanalization rates after endovascular thrombectomy (EVT) for acute ischemic stroke (AIS). Chest radiography can assess the conditions of the aortic arch based on the presence or absence of aortic arch calcification (AoAC). The aim of this study was to investigate the relationship between AoAC on chest radiography and first-pass successful recanalization (modified thrombolysis in cerebral infarction 2b/3 after the first-pass). METHODS: We compared the rate of first-pass successful recanalization between patients with and without AoAC. A total of 193 patients with anterior circulation occlusion who underwent EVT between January 2017 and December 2021 were included. RESULTS: AoAC was observed in 80 (41.5%) patients. Patients with AoAC were older (74.5 ± 7.78 vs. 63.9 ± 12.4 years, p < 0.001), had more EVT attempts (3.04 ± 1.95 vs. 2.01 ± 1.34 times, p < 0.001), and a longer procedural time (71.7 ± 31.2 vs. 48.7 ± 23.1 min, p < 0.001) than those without AoAC. Moreover, Patients with AoAC showed a lower incidence of first-pass successful recanalization (18.8% vs. 47.8%, p < 0.001) and a higher incidence of postprocedural hemorrhage (45.0% vs. 27.7%, p = 0.015) than those without AoAC. On multivariate analysis, AoAC was independently associated with first-pass successful recanalization (odds ratio: 0.239 [0.121-0.475], p < 0.001). CONCLUSIONS: AoAC on chest radiography can be used as a preoperative predictor of successful first-pass recanalization in patients undergoing EVT for AIS.

9.
Int J Mol Sci ; 24(16)2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37628911

RESUMO

Hybrid strains Escherichia coli acquires genetic characteristics from multiple pathotypes and is speculated to be more virulent; however, understanding their pathogenicity is elusive. Here, we performed genome-based characterization of the hybrid of enteropathogenic (EPEC) and enterotoxigenic E. coli (ETEC), the strains that cause diarrhea and mortality in children. The virulence genes in the strains isolated from different sources in the South Korea were identified, and their phylogenetic positions were analyzed. The EPEC/ETEC hybrid strains harbored eae and est encoding E. coli attaching and effacing lesions and heat-stable enterotoxins of EPEC and ETEC, respectively. Genome-wide phylogeny revealed that all hybrids (n = 6) were closely related to EPEC strains, implying the potential acquisition of ETEC virulence genes during ETEC/EPEC hybrid emergence. The hybrids represented diverse serotypes (O153:H19 (n = 3), O49:H10 (n = 2), and O71:H19 (n = 1)) and sequence types (ST546, n = 4; ST785, n = 2). Furthermore, heat-stable toxin-encoding plasmids possessing estA and various other virulence genes and transporters, including nleH2, hlyA, hlyB, hlyC, hlyD, espC, espP, phage endopeptidase Rz, and phage holin, were identified. These findings provide insights into understanding the pathogenicity of EPEC/ETEC hybrid strains and may aid in comparative studies, virulence characterization, and understanding evolutionary biology.


Assuntos
Escherichia coli Enteropatogênica , Escherichia coli Enterotoxigênica , Criança , Humanos , Escherichia coli Enterotoxigênica/genética , Fatores de Virulência/genética , Escherichia coli Enteropatogênica/genética , Filogenia , Genômica , República da Coreia
10.
J Korean Med Sci ; 38(33): e258, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37605497

RESUMO

BACKGROUND: This study aimed to identify the specific T cell co-stimulatory and co-inhibitory factors that play prognostic roles in patients with glioblastoma. Additionally, the unique histone H3 modification enzymes that regulate the expression levels of these specific co-stimulatory and co-inhibitory factors were investigated. METHODS: The medical records of 84 patients newly diagnosed with glioblastoma at our institution from January 2006 to December 2020 were retrospectively reviewed. Immunohistochemical (IHC) staining for T cell co-stimulatory factors (CD27, CD28, CD137, OX40, and ICOS), T cell co-inhibitory factors (CTLA4, PD1, PD-L1, TIM3, and CD200R), and histone H3 lysine modification enzymes (MLL4, RIZ, EZH1, NSD2, KDM5c, JMJD1a, UTX, and JMJD5) was performed on archived paraffin-embedded tissues obtained by biopsy or resection. Quantitative real time-polymerase chain reaction (qRT-PCR) was performed for specific factors, which demonstrated causal relationships, in order to validate the findings of the IHC examinations. RESULTS: The mean follow-up duration was 27.5 months (range, 4.1-43.5 months). During this period, 76 patients (90.5%) died, and the mean OS was 19.4 months (95% confidence interval, 16.3-20.9 months). Linear positive correlations were observed between the expression levels of CD28 and JMJD1a (R2 linear = 0.982) and those of CD137 and UTX (R2 linear = 1.528). Alternatively, significant negative correlations were observed between the expression levels of CTLA4 and RIZ (R2 linear = -1.746) and those of PD-L1 and EZH1 (R2 linear = -2.118); these relationships were confirmed by qRT-PCR. In the multivariate analysis, increased expression levels of CD28 (P = 0.042), and CD137 (P = 0.009), and decreased expression levels of CTLA4 (P = 0.003), PD-L1 (P = 0.020), and EZH1 (P = 0.040) were significantly associated with longer survival. CONCLUSION: These findings suggest that the expression of certain T cell co-stimulatory factors, such as CD28 and CD 137, and co-inhibitory factors, such as CTLA4 and PD-L1 are associated with prognosis of glioblastoma patients.


Assuntos
Glioblastoma , Histonas , Humanos , Antígeno CTLA-4/genética , Antígeno B7-H1 , Lisina , Prognóstico , Antígenos CD28 , Glioblastoma/diagnóstico , Glioblastoma/genética , Epigênese Genética , Estudos Retrospectivos , Linfócitos T
11.
Tissue Eng Regen Med ; 20(6): 905-919, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37531072

RESUMO

BACKGROUND: Adipose-derived stem cells (ADSCs) exert immunomodulatory effects in the treatment of transplant rejection. This study aimed to evaluate the effects of ADSCs on the skin graft survival in a human-to-rat xenograft transplantation model and to compare single and multiple injections of ADSCs. METHODS: Full-thickness human skin xenografts were transplanted into the backs of Sprague-Dawley rats. The rats were injected subcutaneously on postoperative days 0, 3, and 5. The injections were as follows: triple injections of phosphate-buffered saline (PBS group), a single injection of ADSCs and double injections of PBS (ADSC × 1 group), and triple injections of ADSCs (ADSC × 3 group). The immunomodulatory effects of ADSCs on human skin xenografts were assessed. RESULTS: Triple injections of ADSCs considerably delayed cell-mediated xenograft rejection compared with the PBS and ADSC × 1 groups. The vascularization and collagen type 1-3 ratios in the ADSC × 3 group were significantly higher than those in the other groups. In addition, intragraft infiltration of CD3-, CD4-, CD8-, and CD68-positive cells was reduced in the ADSC × 3 group. Furthermore, in the ADSC × 3 group, the expression levels of proinflammatory cytokine interferon-gamma (IFN-γ) were decreased and immunosuppressive prostaglandin E synthase (PGES) was increased in the xenograft and lymph node samples. CONCLUSION: This study presented that triple injections of ADSCs appeared to be superior to a single injection in suppressing cell-mediated xenograft rejection. The immunomodulatory effects of ADSCs are associated with the downregulation of IFN-γ and upregulation of PGES in skin xenografts and lymph nodes.


Assuntos
Tecido Adiposo , Sobrevivência de Enxerto , Humanos , Ratos , Animais , Ratos Sprague-Dawley , Transplante Heterólogo , Xenoenxertos , Células-Tronco
12.
Front Microbiol ; 14: 1179934, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520347

RESUMO

Detecting and identifying the origins of foodborne pathogen outbreaks is a challenging. The Next-Generation Sequencing (NGS) panel method offers a potential solution by enabling efficient screening and identification of various bacteria in one reaction. In this study, new NGS panel primer sets that target 18 specific virulence factor genes from six target pathogens (Bacillus cereus, Yersinia enterocolitica, Staphylococcus aureus, Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus) were developed and optimized. The primer sets were validated for specificity and selectivity through singleplex PCR, confirming the expected amplicon size. Crosscheck and multiplex PCR showed no interference in the primer set or pathogenic DNA mixture. The NGS panel analysis of spiked water samples detected all 18 target genes in a single reaction, with pathogen concentrations ranging from 108 to 105 colony-forming units (CFUs) per target pathogen. Notably, the total sequence read counts from the virulence factor genes showed a positive association with the CFUs per target pathogen. However, the method exhibited relatively low sensitivity and occasional false positive results at low pathogen concentrations of 105 CFUs. To validate the detection and identification results, two sets of quantitative real-time PCR (qPCR) analyses were independently performed on the same spiked water samples, yielding almost the same efficiency and specificity compared to the NGS panel analysis. Comparative statistical analysis and Spearman correlation analysis further supported the similarity of the results by showing a negative association between the NGS panel sequence read counts and qPCR cycle threshold (Ct) values. To enhance NGS panel analysis for better detection, optimization of primer sets and real-time NGS sequencing technology are essential. Nonetheless, this study provides valuable insights into applying NGS panel analysis for multiple foodborne pathogen detection, emphasizing its potential in ensuring food safety.

13.
Front Plant Sci ; 14: 1201875, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37521932

RESUMO

Anthracnose disease is a serious threat to red pepper crops in Korea and many other countries, resulting in considerable yield losses. There are now no effective control techniques available except for fungicide sprays, which may directly impact consumers. This study aims to investigate the biological activity of Trichoderma isolates in controlling red pepper anthracnose caused by Colletotrichum acutatum in vitro and in the field. Out of 11 Trichoderma isolates screened for biocontrol agents against three fungal pathogens, including C. acutatum; two effective Trichoderma isolates, T. atroviride ATR697 (ATR697) and T. longibrachiatum LON701 (LON701) were selected for further investigation. Using the overlapping plates experiment, it was discovered that the volatile organic compounds (VOCs) produced by ATR697 strongly inhibited C. acutatum mycelial growth to a larger extent than the isolate LON701. A cellophane membrane experiment has shown that mycelial growth of C. acutatum was inhibited by 36% and 27% when treated with ATR697 and LON701, respectively. Culture filtrates (CFs) of two Trichoderma isolates inhibited the mycelial growth of C. acutatum in vitro. When red peppers were treated with spore suspensions of LON701 and ATR697, the disease severity (%) was 44.1% and 55.8%, respectively, in a curative method; while the disease severity (%) was 5% and 11.6%, in LON701- and ATR697-treated red peppers, respectively, in a preventive method. These results showed the suppression of disease severity (%) was relatively higher in the preventive method than in the curative method. Furthermore, Trichoderma isolates ATR697 and LON701 were resistant to commercial chemical fungicides in vitro, indicating these strains may also be used synergistically with a chemical fungicide (pyraclostrobin) against the growth of C. acutatum. There was no difference in the inhibition rate (%) of the pathogen between the treatment with LON701 alone and LON701+pyraclostrobin. Based on in vitro findings, ATR697 and LON701 played a role in effectively controlling red pepper anthracnose in field conditions, with LON701 treatment resulting in a disease rate of 14% when compared to ATR697, chemical, and non-treated controls. Overall, our study showed the ability of Trichoderma isolates to control red pepper anthracnose and their potential to develop as novel biocontrol agents to replace chemical fungicides for eco-friendly, sustainable agriculture.

14.
Microorganisms ; 11(5)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37317259

RESUMO

The global emergence of hybrid diarrheagenic E. coli strains incorporating genetic markers from different pathotypes is a public health concern. Hybrids of Shiga toxin-producing and enterotoxigenic E. coli (STEC/ETEC) are associated with diarrhea and hemolytic uremic syndrome (HUS) in humans. In this study, we identified and characterized STEC/ETEC hybrid strains isolated from livestock feces (cattle and pigs) and animal food sources (beef, pork, and meat patties) in South Korea between 2016 and 2020. The strains were positive for genes from STEC and ETEC, such as stx (encodes Shiga toxins, Stxs) and est (encodes heat-stable enterotoxins, ST), respectively. The strains belong to diverse serogroups (O100, O168, O8, O155, O2, O141, O148, and O174) and sequence types (ST446, ST1021, ST21, ST74, ST785, ST670, ST1780, ST1782, ST10, and ST726). Genome-wide phylogenetic analysis revealed that these hybrids were closely related to certain ETEC and STEC strains, implying the potential acquisition of Stx-phage and/or ETEC virulence genes during the emergence of STEC/ETEC hybrids. Particularly, STEC/ETEC strains isolated from livestock feces and animal source foods mostly exhibited close relatedness with ETEC strains. These findings allow further exploration of the pathogenicity and virulence of STEC/ETEC hybrid strains and may serve as a data source for future comparative studies in evolutionary biology.

15.
ACS Appl Mater Interfaces ; 15(26): 31608-31616, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37339325

RESUMO

Negative differential resistance (NDR) based on the band-to-band tunneling (BTBT) mechanism has recently shown great potential in improving the performance of various electronic devices. However, the applicability of conventional BTBT-based NDR devices is restricted by their insufficient performance due to the limitations of the NDR mechanism. In this study, we develop an insulator-to-metal phase transition (IMT)-based NDR device that exploits the abrupt resistive switching of vanadium dioxide (VO2) to achieve a high peak-to-valley current ratio (PVCR) and peak current density (Jpeak) as well as controllable peak and valley voltages (Vpeak/valley). When a phase transition is induced in VO2, the effective voltage bias on the two-dimensional channel is decreased by the reduction in the VO2 resistance. Accordingly, the effective voltage adjustment induced by the IMT results in an abrupt NDR. This NDR mechanism based on the abrupt IMT results in a maximum PVCR of 71.1 through its gate voltage and VO2 threshold voltage tunability characteristics. Moreover, Vpeak/valley is easily modulated by controlling the length of VO2. In addition, a maximum Jpeak of 1.6 × 106 A/m2 is achieved through light-tunable characteristics. The proposed IMT-based NDR device is expected to contribute to the development of various NDR devices for next-generation electronics.

16.
J Allergy Clin Immunol ; 151(5): 1307-1316, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36828081

RESUMO

BACKGROUND: Atopic dermatitis (AD) commonly occurs in children and can progress into severe phenotypes or atopic march, causing significant impairment in quality of life. It is important to find early biomarkers of future onset of AD before any clinical manifestations. OBJECTIVE: We sought to find early predictors of future onset of AD in skin stratum corneum (SC). METHODS: Skin tape strips were collected from the forearm of newborns (n = 111) with and without family history of atopic diseases at the age of 2 months before any signs of clinical AD. Children were clinically monitored until they reached age 2 years to ensure the presence or absence of AD. Skin tape strips were subjected to lipidomic analyses by the liquid chromatography electrospray ionization tandem mass spectrometry and cytokine determination by Meso Scale Discovery U-Plex assay. RESULTS: Overall, 22 of 74 (29.7%) and 5 of 37 (13.5%) infants developed AD in the risk group and the control group, respectively. In the SC of future AD children, protein-bound ceramides were decreased (P < .001), whereas unsaturated sphingomyelin species (P < .0001) and "short-chain" nonhydroxy fatty acid sphingosine and alpha-hydroxy fatty acid sphingosine ceramides were elevated (P < .01 and .05, respectively) as compared with healthy children. Thymic stromal lymphopoietin and IL-13 levels were increased in the SC of future AD subjects (by 74.5% and 78.3%, P = .0022 and P < .0001, respectively). Multivariable logistic regression analysis revealed strong AD predicting power of the combination of family history, type 2 cytokines, and dysregulated lipids, with an odds ratio reaching 54.0 (95% CI, 9.2-317.5). CONCLUSIONS: Noninvasive skin tape strip analysis at age 2 months can identify asymptomatic children at risk of future AD development with a high probability.


Assuntos
Dermatite Atópica , Humanos , Dermatite Atópica/diagnóstico , Citocinas/análise , Esfingosina , Qualidade de Vida , Pele/química , Ceramidas , Ácidos Graxos , Biomarcadores/análise
17.
J Microbiol Biotechnol ; 33(2): 219-227, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36524338

RESUMO

Lettuce is one of the most consumed vegetables worldwide. However, it has potential risks associated with pathogenic bacterial contamination because it is usually consumed raw. In this study, we investigated the changes in the bacterial community on lettuce (Lactuca sativa L.) in Chungcheong-do, South Korea, and the prevalence of foodborne pathogens on lettuce in different seasons using 16S rRNA gene-based sequencing. Our data revealed that the Shannon diversity index showed the same tendency in term of the number of OTUs, with the index being greatest for summer samples in comparison to other seasons. Moreover, the microbial communities were significantly different between the four seasons. The relative abundance of Actinobacteriota varied according to the season. Family Micrococcaceae was most dominant in all samples except summer, and Rhizobiaceae was predominant in the microbiome of the summer sample. At the genus level, the relative abundance of Bacillus was greatest in spring samples, whereas Pseudomonas was greatest in winter samples. Potential pathogens, such as Staphylococcus and Clostridium, were detected with low relative abundance in all lettuce samples. We also performed metagenome shotgun sequencing analysis on the selected summer and winter samples, which were expected to be contaminated with foodborne pathogens, to support 16S rRNA gene-based sequencing dataset. Moreover, we could detect seasonal biomarkers and microbial association networks of microbiota on lettuce samples. Our results suggest that seasonal characteristics of lettuce microbial communities, which include diverse potential pathogens, can be used as basic data for food safety management to predict and prevent future outbreaks.


Assuntos
Lactuca , Microbiota , Lactuca/microbiologia , Estações do Ano , RNA Ribossômico 16S/genética , Microbiota/genética , Metagenoma , Bactérias
18.
J Microbiol Biotechnol ; 33(1): 83-95, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36457187

RESUMO

These days, bacterial detection methods have some limitations in sensitivity, specificity, and multiple detection. To overcome these, novel detection and identification method is necessary to be developed. Recently, NGS panel method has been suggested to screen, detect, and even identify specific foodborne pathogens in one reaction. In this study, new NGS panel primer sets were developed to target 13 specific virulence factor genes from five types of pathogenic Escherichia coli, Listeria monocytogenes, and Salmonella enterica serovar Typhimurium, respectively. Evaluation of the primer sets using singleplex PCR, crosscheck PCR and multiplex PCR revealed high specificity and selectivity without interference of primers or genomic DNAs. Subsequent NGS panel analysis with six artificially contaminated food samples using those primer sets showed that all target genes were multi-detected in one reaction at 108-105 CFU of target strains. However, a few false-positive results were shown at 106-105 CFU. To validate this NGS panel analysis, three sets of qPCR analyses were independently performed with the same contaminated food samples, showing the similar specificity and selectivity for detection and identification. While this NGS panel still has some issues for detection and identification of specific foodborne pathogens, it has much more advantages, especially multiple detection and identification in one reaction, and it could be improved by further optimized NGS panel primer sets and even by application of a new real-time NGS sequencing technology. Therefore, this study suggests the efficiency and usability of NGS panel for rapid determination of origin strain in various foodborne outbreaks in one reaction.


Assuntos
Alimentos Fermentados , Listeria monocytogenes , Microbiologia de Alimentos , Sensibilidade e Especificidade , Reação em Cadeia da Polimerase Multiplex/métodos , Salmonella typhimurium/genética , Escherichia coli/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Listeria monocytogenes/genética
19.
J Korean Neurosurg Soc ; 66(1): 24-32, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35974432

RESUMO

OBJECTIVE: With the recent increase in mechanical thrombectomy (MT) for acute ischemic stroke (AIS), the role of neurosurgeons in AIS treatment has become increasingly important. This study aimed to assess the outcomes of patients with AIS treated by neurosurgeons and neurologists in the emergency room (ER) of a tertiary hospital in South Korea. METHODS: From January 2020 to June 2021, 536 patients with AIS within 24 hours of symptom onset were admitted to our hospital via the ER. Based on the type of doctors who provided initial care for AIS in the ER, patients were divided into two groups : (a) neurosurgeon group (n=119, 22.2%) and (b) neurologist group (n=417, 77.8%). RESULTS: Intravenous tissue plasminogen activator (tPA) was administered in 82 (15.3%) of 536 patients (n=17 [14.3%] in the neurosurgeon group and n=65 [15.6%] in the neurologist group). The door-to-tPA time was not significantly different between both groups (median, 53 minutes; interquartile range [IQR], 45-58 vs. median, 54 minutes; IQR, 46-74; p=0.372). MT was performed in 69 patients (12.9%) (n=25, 36.2% in the neurosurgeon group and n=44, 63.8% in the neurologist group). The neurosurgeon group achieved a shorter door-to-puncture time than the neurologist group (median, 115 minutes; IQR, 107-151 vs. median, 162 minutes; IQR, 117-189; p=0.049). Good clinical outcomes (3-month modified Rankin Scale 0-2) did not differ significantly between the two groups (96/119 [80.7%] vs. 322/417 [77.2%], p=0.454). CONCLUSION: The neurosurgeon group showed similar door-to-treatment time and clinical outcomes to the neurologist group in patients with AIS in the ER. This study suggests that neurosurgeons have comparable abilities to care for patients with AIS in the ER.

20.
Aesthetic Plast Surg ; 47(2): 852-861, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36042026

RESUMO

BACKGROUND: A biological injectable material, paste-type micronized acellular dermal matrix (ADM), has been proven effective in wound healing by filling defects through tissue replacement. This study aimed to compare the efficacy of paste-type micronized ADM on soft tissue augmentation with that of the conventional fillers in animal experiments. METHODS: Two distinct paste-type micronized ADMs, which were mixed with distilled water (mADM) and gelatin (mADM+GEL), respectively, were compared with conventional fillers, hyaluronic acid (HA) and polymethyl methacrylate (COL+PMMA). Thus, four different types of fillers were each injected into the dorsum of nude mice to compare the volume retention and biocompatibility. During the 8-week experimental period, ultrasound and computed tomography (CT) images were obtained for volumetric analysis. Histological evaluation was performed using hematoxylin and eosin and CD 31 staining. RESULTS: According to the CT images at week 8, the mADM and mADM+GEL showed a higher volume persistence rate of 113.54% and 51.12%, compared with 85.09% and 17.65% for HA and COL+PMMA, respectively. The 2-week interval ultrasound images revealed that the mADM showed a volume increase in width rather than in height, and an increase in height for HA did not vary much. Histological analysis showed marked fibrous invasion and neovascularization with the mADM and mADM+GEL compared to that of the conventional fillers. CONCLUSIONS: Paste-type micronized ADM showed soft tissue augmentation with similar effectiveness to that of conventional fillers. Therefore, paste-type micronized ADM has potential as an alternative material for a soft tissue filler in tissue replacement. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Derme Acelular , Preenchedores Dérmicos , Animais , Camundongos , Polimetil Metacrilato/farmacologia , Camundongos Nus , Cicatrização , Preenchedores Dérmicos/farmacologia
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