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BACKGROUND: To analyze the effects of socioeconomic status (type of insurance and income level) and cancer stage on the survival of patients with liver cancer in Korea. METHODS: A retrospective cohort study was constructed using data from the Healthcare Big Data Platform project in Korea between January 1, 2007, and December 31, 2017. A total of 143,511 patients in Korea diagnosed with liver cancer (International Classification of Diseases, 10th Revision [ICD-10] codes C22, C220, and C221) were followed for an average of 11 years. Of these, 110,443 died. The patient's insurance type and income level were used as indicators of socioeconomic status. Unadjusted and adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using a Cox proportional hazards regression model to analyze the relationship between the effects of sex, age, and cancer stage at first diagnosis (Surveillance, Epidemiology, and the End Results; SEER), type of insurance, and income level on the survival of patients with liver cancer. The interactive effects of the type of insurance, income level, and cancer stage on liver cancer death were also analyzed. RESULTS: The lowest income group (medical aid) showed a higher risk for mortality (HR (95% CI); 1.37 (1.27-1.47) for all patients, 1.44 (1.32-1.57) for men, and 1.16 (1.01-1.34) for women) compared to the highest income group (1-6) among liver cancer (ICD-10 code C22) patients. The risk of liver cancer death was also higher in the lowest income group with a distant cancer stage (SEER = 7) diagnosis than for any other group. CONCLUSION: Liver cancer patients with lower socioeconomic status and more severe cancer stages were at greater risk of death. Reducing social inequalities is needed to improve mortality rates among patients in lower social class groups who present with advanced cancer.
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Neoplasias Hepáticas , Classe Social , Masculino , Humanos , Feminino , Estudos de Coortes , Estudos Retrospectivos , Fatores Socioeconômicos , República da Coreia/epidemiologiaRESUMO
Jasmonic acid (JA) and ethylene (ET) signaling modulate plant defense against necrotrophic pathogens in a synergistic and interdependent manner, while JA and ET also have independent roles in certain processes, e.g. in responses to wounding and flooding, respectively. These hormone pathways lead to transcriptional reprogramming, which is a major part of plant immunity and requires the roles of transcription factors. ET response factors are responsible for the transcriptional regulation of JA/ET-responsive defense genes, of which ORA59 functions as a key regulator of this process and has been implicated in the JA-ET crosstalk. We previously demonstrated that Arabidopsis (Arabidopsis thaliana) GDSL LIPASE 1 (GLIP1) depends on ET for gene expression and pathogen resistance. Here, promoter analysis of GLIP1 revealed ERELEE4 as the critical cis-element for ET-responsive GLIP1 expression. In a yeast one-hybrid screening, ORA59 was isolated as a specific transcription factor that binds to the ERELEE4 element, in addition to the well-characterized GCC box. We found that ORA59 regulates JA/ET-responsive genes through direct binding to these elements in gene promoters. Notably, ORA59 exhibited a differential preference for GCC box and ERELEE4, depending on whether ORA59 activation is achieved by JA and ET, respectively. JA and ET induced ORA59 phosphorylation, which was required for both activity and specificity of ORA59. Furthermore, RNA-seq and virus-induced gene silencing analyses led to the identification of ORA59 target genes of distinct functional categories in JA and ET pathways. Our results provide insights into how ORA59 can generate specific patterns of gene expression dynamics through JA and ET hormone pathways.
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Proteínas de Arabidopsis/genética , Arabidopsis/genética , Ciclopentanos/metabolismo , Etilenos/metabolismo , Oxilipinas/metabolismo , Imunidade Vegetal/genética , Fatores de Transcrição/genética , Arabidopsis/imunologia , Proteínas de Arabidopsis/metabolismo , DNA de Plantas/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Although biodegradable plastics are gradually emerging as an effective solution to alleviate the burgeoning plastic pollution, their performance is currently trivial for commercialization. A proposed two-pronged strategy to overcome this limitation includes (1) preparation of the nanocomposites from biorenewable nano-fillers to preserve their biodegradability and (2) tailoring their properties to meet the diverse demands in various applications. Herein, we report the preparation of biodegradable nanocomposites composed of poly(butylene succinate) (PBS) and cellulose nanocrystals (CNCs) (loading of 0.2-3.0 wt%) and propose a rheological strategy to tailor their performances. Depending on the shear frequencies, the rheological evaluation revealed two percolation thresholds at approximately 0.8 and 1.5 wt%. At high shear frequencies, the disappearance of the first threshold (0.8 wt%) and the sole persistence of the second one (1.5 wt%) indicated the collapse of the immature network of partially interconnected CNCs. The tensile and hydrolytic properties of the nanocomposites were found to undergo drastic changes at the thresholds. The tensile strength increased by 17% (from 33.3 to 39.2 MPa) up to 0.8 wt% CNC loading. However, the reinforcing efficiency of CNC decreases sharply with further incorporation, reaching nearly zero at 1.5 wt%. On the other hand, hydrolytic degradation of the nanocomposites was rapidly accelerated above 1.5 wt% CNC loading. Therefore, a thorough understanding of the rheological properties of nanocomposites is essential for the design and development of materials with tailored properties.
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In this study, HER2 RNA aptamers were conjugated to mertansine (DM1) and the anti-cancer effectiveness of the conjugate was evaluated in HER2-overexpressing breast cancer models. The conjugate of HER2 aptamer and anticancer drug DM1 (aptamer-drug conjugate, ApDC) was prepared and analyzed using HPLC and mass spectrometry. The cell-binding affinity and cytotoxicity of the conjugate were determined using confocal microscopy and WST-1 assay. The in vivo anti-tumoral efficacy of ApDC was also evaluated in mice carrying BT-474 breast tumors overexpressing HER2. The synthesized HER2-specific RNA aptamers were able to specifically and efficiently bind to HER-positive BT-474 breast cancer cells, but not to HER2-negative MDA-MB-231 breast cancer cells. Also, the HER2-specific ApDC showed strong toxicity to the target cells, BT-474, but not to MDA-MB-231 cells. According to the in vivo analyses drawn from the mouse xenografts of BT-747 tumor, the ApDC was able to more effectively inhibit the tumor growth. Compared to the control group, the mice treated with the ApDC showed a significant reduction of tumor growth. Besides, any significant body weight losses or hepatic toxicities were monitored in the ApDC-treated mice. This research suggests the HER2 aptamer-DM1 conjugate as a target-specific anti-cancer modality and provides experimental evidence supporting its enhanced effectiveness for HER2-overexpressing target tumors. This type of aptamer-conjugated anticancer drug would be utilized as a platform structure for the development of versatile targeted high-performance anticancer drugs by adopting the easy deformability and high affinity of aptamers.
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Aptâmeros de Nucleotídeos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Receptor ErbB-2/genética , Animais , Apoptose , Aptâmeros de Nucleotídeos/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Receptor ErbB-2/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
In the original version of the article the authors incorrectly stated that: "One case study provided evidence of some improvements in motor performance and spasticity [19], while several other studies only provided evidence on the feasibility of UER as an assessment tool; however, the fact that the manufacturer funded these studies lessens their objectivity [15, 20-24]." This is not correct as the manufacturers did not fund the studies. The correct phrase therefore should have read: "One case study provided evidence of some improvements in motor performance and spasticity [19], while several other studies provided evidence focusing more on the feasibility of UER rather than the clinical efficacy [15, 20-24]." The authors would like to apologise for this error.This has been corrected in both the PDF and HTML versions of the Article.
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STUDY DESIGN: A pilot randomized controlled trial. OBJECTIVES: To evaluate the clinical efficacy of upper limb robotic therapy in people with tetraplegia. SETTING: Inpatient rehabilitation hospital in Seoul, Korea. METHODS: Participants were randomly allocated to a robotic therapy (RT) or occupational therapy (OT) group. Both groups received usual care plus 30 min of additional therapy per day for 4 weeks. The additional therapy provided to the OT group was OT, and the additional therapy provided to RT group was RT using the Armeo Power. Primary outcomes were the Medical Research Council scale of each key muscle and Upper Extremity Motor Score (UEMS) for the trained arm. Secondary outcomes were the Spinal Cord Independence Measurement version III (SCIM-III) subscale and total score. Evaluations were performed at baseline and 4 weeks. RESULTS: A total of 34 individuals with tetraplegia were included; 17 in each group. At 4 weeks, the median (IQR) change in UEMS in the RT group was 1/25 (0 to 3) points compared with 0/25 (-1 to 1) points in the OT group (p = 0.03). The median (IQR) change in total SCIM-III score in the RT group was 7/100 (1.5 to 11) points compared with 0/100 (-8 to 4) points in the OT group (p < 0.01). CONCLUSIONS: There were small improvements in motor strength and SCIM-III scores in the RT group, but there were no statistically significant differences between the groups. Further studies are required for a better understanding of the effects of RT for people with tetraplegia.
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Reabilitação Neurológica , Quadriplegia/reabilitação , Robótica , Terapia Assistida por Computador , Vértebras Cervicais , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Reabilitação Neurológica/instrumentação , Terapia Ocupacional , Projetos Piloto , Quadriplegia/etiologia , Método Simples-Cego , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/reabilitação , Resultado do TratamentoRESUMO
BACKGROUND: This study aimed to investigate resilience as a protective factor for depressive mood and anxiety among Korean employees. METHODS: Participants were employees of eight private and local government organizations in Korea, aged 19 to 65 years. A self-report questionnaire that included items on resilience, job stress, levels of depression and anxiety, and socio-demographic factors, was administered to 1,079 Korean employees, with 1,076 valid responses. We performed hierarchical linear regression analyses with the levels of depression and anxiety scores as dependent variables. RESULTS: Being women and having a high level of job stress were associated with greater depressive mood and anxiety. In contrast, resilience was negatively related to depressive mood and anxiety, after adjusting for demographic variables and the level of job stress. Among the five factors for resilience, "support" and "hardiness" were protective factors for depressive mood and anxiety after adjusting for demographic variables and the level of job stress. CONCLUSION: Based on the results of the current study, we suggest that focusing on the resilience of employees, especially on "support" and "hardiness," factors as well as developing and engaging in interventions that increase resilience in the workplace, can protect against depressive mood and anxiety, especially for those with high levels of job stress.
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Transtornos de Ansiedade/patologia , Transtorno Depressivo/patologia , Resiliência Psicológica , Adulto , Idoso , Transtornos de Ansiedade/psicologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Saúde Ocupacional , Estresse Ocupacional , Fatores de Proteção , República da Coreia , Autorrelato , Índice de Gravidade de Doença , Inquéritos e Questionários , Local de Trabalho , Adulto JovemRESUMO
From graphene oxide wrapped iron oxide particles with etching/reduction process, high-performance anode and cathode materials of lithium-ion hybrid supercapacitors are obtained in the same process with different etching conditions, which consist of partially etched crumpled graphene (CG) wrapped spiky iron oxide particles (CG@SF) for a battery-type anode, and fully etched CG for a capacitive-type cathode. The CG is formed along the shape of spikily etched particles, resulting in high specific surface area and electrical conductivity, thus the CG-based cathode exhibits remarkable capacitive performance of 210 F g-1 and excellent rate capabilities. The CG@SF can also be ideal anode materials owing to spiky and porous morphology of the particles and tightly attached crumpled graphene onto the spiky particles, which provides structural stability and low contact resistance during repetitive lithiation/delithiation processes. The CG@SF anode shows a particularly high capacitive performance of 1420 mAh g-1 after 270 cycles, continuously increases capacity beyond the 270th cycle, and also maintains a high capacity of 170 mAh g-1 at extremely high speeds of 100 C. The full-cell exhibits a higher energy density up to 121 Wh kg-1 and maintains high energy density of 60.1 Wh kg-1 at 18.0 kW kg-1 . This system could thus be a practical energy storage system to fill the gap between batteries and supercapacitors.
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Realizing the significant roles of vicinal-dithiol proteins (VDPs) in maintaining the cellular redox homeostasis and their implication in many diseases, we synthesized a smart arsenate based fluorescent probe 1 which can preferentially target the mitochondrial membrane-bound vicinal dithiol proteins (VDPs), especially voltage-dependent anion channel (VDAC2). The probe targetability was demonstrated by in vitro studies such as colocalization, stimulated emission depletion (STED) super-resolution imaging, proteomic MS/MS analysis, and Western blot analysis. The probe represents a rare example of fluorescence labeling of mitochondrial membrane-bound VDPs and can provide a new way to construct VDPs-specific fluorescent probes to gain deeper understanding of their roles in mitochondrial-related disorders.
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Arseniatos/química , Corantes Fluorescentes/química , Proteínas de Transporte da Membrana Mitocondrial/análise , Membranas Mitocondriais/química , Compostos de Sulfidrila/análise , Células HeLa , Humanos , Microscopia de Fluorescência/métodos , Membranas Mitocondriais/ultraestrutura , Imagem Óptica/métodos , Oxirredução , Canal de Ânion 2 Dependente de Voltagem/análiseRESUMO
We have studied an orientation structure of self-assembled block copolymers (dPS-b-PMMA) of deuterated polystyrene (dPS) and poly(methyl methacrylate) (PMMA) confined between graphene oxide (GO) surfaces. The results of combination techniques, such as neutron reflectivity, time-of-flight secondary-ion mass spectrometry, grazing-incidence small-angle X-ray scattering, and scanning electron microscopy, show that self-assembled domains of the block copolymers in thin films near the GO sheets are oriented perpendicular to the surface of the GO monolayers, in contrast to the horizontal lamellar structure of the copolymer thin film in the absence of the GO monolayers. This is due to the amphiphilic nature of the GO, which leads to a nonpreferential interaction of both dPS and PMMA blocks. Double-sided confinement with the GO monolayers further extends the ordering behavior of the dPS-b-PMMA thin films. Continuous vertical orientation of the block copolymer thin films is also obtained in the presence of alternating GO layers within thick copolymer films.
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The elucidation of the cause of Alzheimer's disease remains one of the greatest questions in neurodegenerative research. The lack of highly reliable low-cost sensors to study the structural changes in key proteins during the progression of the disease is a contributing factor to this lack of insight. In the current work, we describe the rational design and synthesis of two fluorescent BODIPY-based probes, named Tau 1 and Tau 2. The probes were evaluated on the molecular surface formed by a fibril of the PHF6 (306VQIVYK311) tau fragment using molecular docking studies to provide a potential molecular model to rationalize the selectivity of the new probes as compared to a homologous Aß-selective probe. The probes were synthesized in a few steps from commercially available starting products and could thus prove to be highly cost-effective. We demonstrated the excellent photophysical properties of the dyes, such as a large Stokes shift and emission in the near-infrared window of the electromagnetic spectrum. The probes demonstrated a high selectivity for self-assembled microtubule-associated protein tau (Tau protein), in both solution and cell-based experiments. Moreover, the administration to an acute murine model of tauopathy clearly revealed the staining of self-assembled hyperphosphorylated tau protein in pathologically relevant hippocampal brain regions. Tau 1 demonstrated efficient blood-brain barrier penetrability and demonstrated a clear selectivity for tau tangles over Aß plaques, as well as the capacity for in vivo imaging in a transgenic mouse model. The current work could open up avenues for the cost-effective monitoring of the tau protein aggregation state in animal models as well as tissue staining. Furthermore, these fluorophores could serve as the basis for the development of clinically relevant sensors, for example based on PET imaging.
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We investigate the effect of adding graphene oxide (GO) sheets at the polymer-polymer interface on the dewetting dynamics and compatibility of immiscible polymer bilayer films. GO monolayers are deposited at the poly(methyl methacrylate) (PMMA)-polystyrene (PS) interface by the Langmuir-Schaefer technique. GO monolayers are found to significantly inhibit the dewetting behavior of both PMMA films (on PS substrates) and PS films (on PMMA substrates). This can be interpreted in terms of an interfacial interaction between the GO sheets and these polymers, which is evidenced by the reduced contact angle of the dewet droplets. The favorable interaction of GO with both PS and PMMA facilitates compatibilization of the immiscible polymer bilayer films, thereby stabilizing their bilayer films against dewetting. This compatibilization effect is verified by neutron reflectivity measurements, which reveal that the addition of GO monolayers broadens the interface between PS and the deuterated PMMA films by 2.2 times over that of the bilayer in the absence of GO.
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Control of a two-dimensional (2D) structure of assembled graphene oxide (GO) sheets is highly desirable for fundamental research and potential applications of graphene devices. We show that an alkylamine surfactant, i.e., octadecylamine (ODA), Langmuir monolayer can be utilized as a template for adsorbing highly hydrophilic GO sheets in an aqueous subphase at the liquid-gas interface. The densely packed 2-D monolayer of such complex films was obtained on arbitrary substrates by applying Langmuir-Schaefer or Langmuir-Blodgett technique. Morphology control of GO sheets was also achieved upon compression by tuning the amount of spread ODA molecules. We found that ODA surfactant monolayers prevent GO sheets from sliding, resulting in formation of wrinkling rather than overlapping at the liquid-gas interface during the compression. The morphology structures did not change after a graphitization procedure of chemical hydrazine reduction and thermal annealing treatments. Since morphologies of graphene films are closely correlated to the performance of graphene-based materials, the technique employed in this study can provide a route for applications requiring wrinkled graphenes, ranging from nanoelectronic devices to energy storage materials, such as supercapacitors and fuel cell electrodes.
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This paper provides a comprehensive overview of the Cancer Public Library Database (CPLD), established under the Korean Clinical Data Utilization for Research Excellence project (K-CURE). The CPLD links data from four major population-based public sources: the Korea National Cancer Incidence Database in the Korea Central Cancer Registry, cause-of-death data in Statistics Korea, the National Health Information Database in the National Health Insurance Service, and the National Health Insurance Research Database in the Health Insurance Review & Assessment Service. These databases are linked using an encrypted resident registration number. The CPLD, established in 2022 and updated annually, comprises 1,983,499 men and women newly diagnosed with cancer between 2012 and 2019. It contains data on cancer registration and death, demographics, medical claims, general health checkups, and national cancer screening. The most common cancers among men in the CPLD were stomach (16.1%), lung (14.0%), colorectal (13.3%), prostate (9.6%), and liver (9.3%) cancers. The most common cancers among women were thyroid (20.4%), breast (16.6%), colorectal (9.0%), stomach (7.8%), and lung (6.2%) cancers. Among them, 571,285 died between 2012 and 2020 owing to cancer (89.2%) or other causes (10.8%). Upon approval, the CPLD is accessible to researchers through the K-CURE portal. The CPLD is a unique resource for diverse cancer research to investigate medical use before a cancer diagnosis, during initial diagnosis and treatment, and long-term follow-up. This offers expanded insight into healthcare delivery across the cancer continuum, from screening to end-of-life care.
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STAT3 was recently reported to suppress tumor invasion in Apc(min)(/+) mice. We investigated the mechanisms by which STAT3 inhibits intestinal epithelial tumors using Apc(min)(/+)/Stat3(IEC-KO) mice (intestinal epithelial cell (IEC)-specific deletion of STAT3 in the Apc(min)(/+) background) to determine the role of STAT3 in carcinogenesis in vivo as well as colorectal cancer cell lines in vitro. To inhibit invasion of IEC tumors, STAT3 functions as a molecular adaptor rather than a transcription factor. Accordingly, the tumors in Apc(min)(/+)/Stat3(IEC-KO) mice undergo adenoma-to-carcinoma transition and acquire an invasive phenotype. Similarly, STAT3 knockdown in a colorectal cell line enhances IEC invasion. We demonstrate that STAT3 down-regulates SNAI (Snail-1) expression levels and hence suppresses epithelial-mesenchymal transition of colorectal cancer cells. Mechanistically, STAT3 facilitates glycogen synthase kinase (GSK) 3ß-mediated degradation of SNAI by regulating phosphorylation of GSK3ß. Our data identified a new role for STAT3 in the adenoma-to-carcinoma sequence of intestinal tumors.
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Adenoma/patologia , Carcinoma/patologia , Genes APC , Fator de Transcrição STAT3/fisiologia , Fatores de Transcrição/fisiologia , Animais , Sequência de Bases , Proliferação de Células , Primers do DNA , Regulação para Baixo , Transição Epitelial-Mesenquimal , Neoplasias Intestinais/patologia , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase , RNA Interferente Pequeno , Fator de Transcrição STAT3/genética , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genéticaRESUMO
PURPOSE: Subpial hemorrhage (SPH) is a subtype of intracranial hemorrhage characterized by damage to the adjacent brain parenchyma. The aim of this study was to describe the sonographic features of SPH in neonates. METHODS: The cranial ultrasound (US) findings of neonates with SPH confirmed by brain magnetic resonance imaging (MRI) were analyzed retrospectively. Initial and follow-up US and MRI scans were reviewed by two pediatric radiologists who were blinded to both clinical history and outcomes. The US features were compared with the MRI findings. RESULTS: Sixteen patients were included (median gestational age, 38 weeks; range, 26 to 40 weeks; 69% term). SPH was detected most often in the temporal lobe (63%), and multiple SPHs were found in seven of 16 neonates, based on MRI. Acute SPH with an underlying venous infarct (UVI) was detected on US in 15 of 16 patients: small or large fan-shaped hyperechoic lesions (n=7 and 4, respectively) and gyriform hyperechoic lesions (n=4). The sonographic yin-yang sign was observed in three of the four large fan-shaped SPH cases. The accompanying findings on US were intraventricular hemorrhage (four out of six MRI-confirmed cases), and concurrent periventricular venous infarcts (five out of nine MRI-confirmed cases). In five patients, subpial cysts were observed on follow-up US or MRI (n=4 and n=4, respectively). CONCLUSION: Acute SPH with UVI can appear as a peripheral fan-shaped or gyriform hyperechoic lesion on cranial US. SPH can be detected and suspected based on the US features of SPH with the accompanying findings.
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Anti-CD19 chimeric antigen receptor (CAR)-T cells have improved the outcomes of patients with B cell leukemia and lymphoma. However, their applications and positive outcomes remain limited. CAR-T cells are currently restricted to autologous blood as their source and their use can lead to downregulation of CD19 expression along with complications such as graft-versus-host disease and cytokine release syndrome. The present study aimed to develop anti-CD19/CD22 bispecific CAR structures using an anti-CD22 monoclonal antibody clone from chickens and analyze them in natural killer (NK)-92 cells, a human NK cell line, in vitro and in vivo. Anti-CD19/CD22 CAR-NK-92 cell cytotoxicity was assessed by the survival of target cells and counted using flow cytometry. Anti-CD22/CD19 and loop-structured anti-CD19/CD22 bi-specific CAR-NK-92 cells showed improved efficacy against OCI-Ly7 cells, a human B cell lymphoma cell line, compared with other CAR structures. These results demonstrate the potential of anti-CD19/CD22 bispecific CAR-NK cells and suggested that optimizing CAR structures in NK cells can improve the efficacy of CAR therapy.
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The Lactococcus taiwanensis strain K_LL004 was isolated from the gut of a grasshopper (Oxya chinensis sinuosa) collected from local farm in Korea. L. taiwanensis strain K_LL004 is the functional probiotic candidate with an ability to hydrolyse plant polysaccharides. The complete genome of the L. taiwanensis strain K_LL004 contains one circular chromosome (1,995,099 bp) with a guanine + cytosine (GC) content of 38.8%. Moreover, 1,929 Protein-coding sequence, 19 rRNA genes, and 62 tRNA genes were identified based on results of annotation. L. taiwanensis strain K_LL004 has a gene, which encodes hydrolytic enzymes such as beta-glucosidase and beta-xylosidase, that hydrolyzes plant polysaccharides.
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Antibiotics have been used in livestock production for not only treatment but also for increasing the effectiveness of animal feed, aiding animal growth, and preventing infectious diseases at the time when immunity is lowered due to stress. South Korea and the EU are among the countries that have prohibited the use of antibiotics for growth promotion in order to prevent indiscriminate use of antibiotics, as previous studies have shown that it may lead to increase in cases of antibiotic-resistant bacteria. Therefore, this study evaluated the number of antibiotic resistance genes in piglets staging from pre-weaning to weaning. Fecal samples were collected from 8 piglets just prior to weaning (21 d of age) and again one week after weaning (28 d of age). Total DNA was extracted from the 200 mg of feces collected from the 8 piglets. Whole metagenome shotgun sequencing was carried out using the Illumina Hi-Seq 2000 platform and raw sequence data were imported to Metagenomics Rapid Annotation using Subsystem Technology (MG-RAST) pipeline for microbial functional analysis. The results of this study did not show an increase in antibiotic-resistant bacteria although confirmed an increase in antibiotic-resistant genes as the consequence of changes in diet and environment during the experiment.
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The foodborne illness is the important public health concerns, and the livestock feces are known to be one of the major reservoirs of foodborne pathogens. Also, it was reported that 45.5% of foodborne illness outbreaks have been associated with the animal products contaminated with the livestock feces. In addition, it has been known that the persistence of a pathogens depends on many potential virulent factors including the various virulent genes. Therefore, the first step to understanding the public health risk of livestock feces is to identify and describe microbial communities and potential virulent genes that contribute to bacterial pathogenicity. We used the whole metagenome shotgun sequencing to evaluate the prevalence of foodborne pathogens and to characterize the virulence associated genes in pig and chicken feces. Our data showed that the relative abundance of potential foodborne pathogens, such as Bacillus cereus was higher in chickens than pigs at the species level while the relative abundance of foodborne pathogens including Campylobacter coli was only detected in pigs. Also, the microbial functional characteristics of livestock feces revealed that the gene families related to "Biofilm formation and quorum sensing" were highly enriched in pigs than chicken. Moreover, the variety of gene families associated with "Resistance to antibiotics and toxic compounds" were detected in both animals. These results will help us to prepare the scientific action plans to improve awareness and understanding of the public health risks of livestock feces.