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BACKGROUND: Between July 2, 2021, and September 20, 2022, a Mycobacterium bovis outbreak occurred among exhibition animals at a zoo in the Republic of Korea. This study was conducted to assess the likelihood of M. bovis transmission to human contacts through a contact investigation and to implement preventive treatment for latent tuberculosis infection (LTBI). METHODS: In this descriptive study, the Korea Disease Control and Prevention Agency conducted a contact investigation, which included interviews, interferon-gamma release assay (IGRA) tests, and chest X-rays. Contacts underwent IGRA testing on 2 occasions: initial testing of 29 contacts (15 in the first cluster of infection and 14 in the second cluster) and follow-up testing of the 15 contacts in the first cluster. RESULTS: The study included 29 participants, 18 of whom were male (62.1%) and 11 female (37.9%). The mean participant age was 37.3 years (standard deviation, 9.6 years). In the initial IGRA tests, 6 of the 29 participants tested positive, indicating a prevalence of 20.7%. Following prolonged exposure, 1 additional positive case was detected in follow-up testing, raising the prevalence of LTBI to 24.1%. None of the contacts had active tuberculosis. Among the 7 individuals with positive results, 2 (28.6%) underwent treatment for LTBI. CONCLUSION: This study faced challenges in confirming the transmission of M. bovis infection from infected animals to humans in the Republic of Korea. Nevertheless, adopting a One Health approach necessitates the implementation of surveillance systems and infection control protocols, particularly for occupational groups at high risk of exposure.
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BACKGROUND/OBJECTIVES: Although iodine is essential for thyroid hormone production and controls many metabolic processes, there are few reports on the iodine intake of the population because of the scarcity of information on the iodine content in food. This study estimated the iodine intake of Koreans from brown seaweed, the major source of iodine in nature. SUBJECTS/METHODS: The dietary intake data from the recent Korea National Health and Nutrition Examination Survey (2016-2021) and the iodine content in brown seaweed were used for the estimation. Nationwide brown seaweed samples were collected and prepared using the representative preparation/cooking methods in the Koreans' diet before iodine analysis by alkaline digestion followed by inductively coupled plasma mass spectrometry. RESULTS: The mean (± SE) iodine intake from sea mustard was 96.01 ± 2.36 µg/day in the Korean population. Although the iodine content in kelp was approximately seven times higher than that in sea mustard, the mean iodine intake from kelp (except broth) was similar to that of sea mustard, 115.58 ± 7.71 µg/day, whereas that from kelp broth was 347.57 ± 10.03 µg/day. The overall mean iodine intake from brown seaweed was 559.16 ± 13.15 µg/day, well over the Recommended Nutrient Intake of iodine for Koreans. Nevertheless, the median intake was zero because only 37.6% of the population consumed brown seaweed on the survey date, suggesting that Koreans do not consume brown seaweed daily. CONCLUSION: The distribution of the usual intake of iodine from brown seaweed in Koreans would be much tighter, resulting in a lower proportion of people exceeding the tolerable upper intake levels and possibly a lower mean intake than this study presented. Further study evaluating the iodine nutriture of Koreans based on the usual intake is warranted. Nevertheless, this study adds to the few reports on the iodine nutriture of Koreans.
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5-Aminosalicylic acid (5-ASA) is recommended for managing ulcerative colitis. Common adverse effects associated with 5-ASA include gastrointestinal disorders, headaches, and skin rashes. Perimyocarditis induced by 5-ASA is a rare adverse effect, with only a limited number of cases reported. This paper presents a case of 5-ASA-induced perimyocarditis in a 29-year-old female who had been taking 5-ASA for three weeks. The patient was admitted to the emergency department with dyspnea, chest discomfort, and fever. She subsequently underwent laboratory investigations, including electrocardiography, transthoracic echocardiography, chest computed tomographic angiography, cardiac magnetic resonance imaging, and heart biopsy. Intravenous steroid was administered, and 5-ASA was discontinued. The patient's signs and symptoms improved significantly within a few days of discontinuing 5-ASA, leading to her subsequent discharge. This case highlights the importance of considering perimyocarditis in patients exhibiting cardiac symptoms during 5-ASA therapy, despite it being a rare adverse effect. Drug withdrawal in such cases may lead to rapid clinical improvement.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal , Colitis, Ulcerative , Echocardiography , Electrocardiography , Mesalamine , Myocarditis , Humans , Female , Mesalamine/therapeutic use , Mesalamine/adverse effects , Colitis, Ulcerative/drug therapy , Colitis, Ulcerative/diagnosis , Adult , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Myocarditis/diagnosis , Myocarditis/chemically induced , Myocarditis/drug therapy , Magnetic Resonance Imaging , Tomography, X-Ray Computed , Computed Tomography AngiographyABSTRACT
BACKGROUND: We examined factors contributing to the transmission of an acute respiratory virus within multi-use facilities, focusing on an outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a movie theater in the Republic of Korea. METHODS: This retrospective cohort study involved a descriptive analysis of 48 confirmed cases. Logistic regression was applied to a cohort of 80 theater attendees to identify risk factors for infection. The infection source and transmission route were determined through gene sequencing data analysis. RESULTS: Of the 48 confirmed cases, 35 were theater attendees (72.9%), 10 were family members of attendees (20.8%), 2 were friends (4.2%), and 1 was an employee (2.1%). Among the 80 individuals who attended the 3rd to 5th screenings of the day, 35 became infected, representing a 43.8% attack rate. Specifically, 28 of the 33 third-screening attendees developed confirmed SARSCoV-2, constituting an 84.8% attack rate. Furthermore, 11 of the 12 cases epidemiologically linked to the theater outbreak were clustered monophyletically within the AY.69 lineage. At the time of the screening, 35 individuals (72.9%) had received 2 vaccine doses. However, vaccination status did not significantly influence infection risk. Multivariate analysis revealed that close contacts had a 15.9-fold higher risk of infection (95% confidence interval, 4.37-78.39) than casual contacts. CONCLUSION: SARS-CoV-2 transmission occurred within the theater, and extended into the community, via a moviegoer who attended the 3rd screening during the viral incubation period after contracting the virus from a family member. This study emphasizes the importance of adequate ventilation in theaters.
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BACKGROUND: In March 2023, an alternative school in the Republic of Korea reported 12 cases of shigellosis. This study aims to analyze the epidemiological characteristics in order to determine the cause of the cluster outbreak of shigellosis and to develop prevention strategies. METHODS: This study focused on 12 patients with confirmed Shigella infection and investigated their demographics, clinical features, epidemiology, diagnostics, and antimicrobial susceptibility. Following the identification of Shigella, we conducted follow-up rectal smear cultures to manage patients, implementing isolation and control measures. RESULTS: This study investigated the emergence of multidrug-resistant Shigella following missionary activities in Cambodia, documenting a cluster infection within an alternative school in Daejeon, the Republic of Korea. The outbreak affected 56 participants, resulting in the confirmation of 12 cases. The incidence rates varied by gender and occupation, with higher rates among males and teachers. All 12 cases demonstrated multidrug resistance. Challenges included delayed pathogen confirmation and suboptimal adherence to isolation criteria. The incident prompted revisions in the criteria for isolation release, focusing on symptom resolution. The study underscores the necessity for strengthened surveillance, educational initiatives focusing on prevention in endemic areas, and improved oversight of unlicensed educational establishments. CONCLUSION: Successful response strategies included swift situation assessment, collaborative efforts, effective infection control measures, and modified criteria for isolation release. Continued surveillance of multidrug-resistant strains is recommended, especially in regions with a high prevalence.
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Early and accurate detection of viruses in children might help prevent transmission and severe diseases. In this study, the severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) detection in children was evaluated using saliva specimens with a Proteinase K (PTK)-based RNA preparation, as saliva collection is a simple and noninvasive procedure, even in young children, with fewer concerns about sample contamination. The saliva-based PTK and the conventional paired nasopharyngeal aspiration (NPA)-based detection methods were compared between COVID-19-positive and -negative children. In addition, the detection rate for SARS-COV-2 and the difference between admission and discharge by the saliva-based PTK method was tested in COVID-19 patients. The diagnostic accuracy of the saliva-based PTK method was 98.8% compared to NP swab-based reverse transcriptase polymerase chain reaction. Saliva samples showed high sensitivity (94.1%) and specificity (100%) when using the PTK method. Furthermore, the saliva-based PTK method significantly reduced the test processing time by 2 h. Notably, Ct values at discharge increased in saliva samples compared with those at admission, which might indicate patients' clinical conditions or virus activity. In conclusion, the saliva-based PTK implemented in this study streamlines RNA extraction, making the process faster, safer, and more cost-effective, demonstrating that this method is a rapid and reliable diagnostic tool for SARS-CoV-2 detection in children.
Subject(s)
COVID-19 , Saliva , Child , Humans , Child, Preschool , SARS-CoV-2/genetics , Endopeptidase K , COVID-19/diagnosis , RNA , Specimen Handling , Nasopharynx , COVID-19 TestingABSTRACT
Transient and rapid increase in cytosolic Ca2+ plays a crucial role in plant-pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI). Cyclic nucleotide-gated channels (CNGCs) have been implicated in mediating this Ca2+ influx; however, their regulatory mechanisms remain poorly understood. Here, we have found that AVRblb2 requires the calmodulin (CaM) and calmodulin-like (CML) proteins as co-factors to interact with the NbCNGCs, resulting in the formation of AVRblb2-CaM/CML-NbCNGCs complex. Furthermore, CaM and CML are dissociated from NbCNGC18 during PTI response to increase Ca2+ influx; however, Avrblb2 inhibits calcium channel activation by disrupting the release of CaM and CML from NbCNGC18. Following recognition of PAMP, NbCNGC18 forms active heteromeric channels with other NbCNGCs, which may give selectivity of CNGC complex against diverse signals for fine-tuning of cytosolic Ca2+ level to mediate appropriate responses. Silencing of multiple NbCNGCs compromised the function of AVRblb2 on the pathogenicity of Phytophthora infestans, confirming that AVRblb2 contributes to pathogen virulence by targeting CNGCs. Our findings provide new insights into the regulation of CNGCs in PTI and the role of pathogen effectors in manipulating host cell physiology to promote infection.
Subject(s)
Calmodulin , Phytophthora infestans , Calmodulin/metabolism , Cyclic Nucleotide-Gated Cation Channels/metabolism , Calcium/metabolism , Innate Immunity Recognition , Phytophthora infestans/metabolism , Nucleotides, Cyclic/metabolism , Plant ImmunityABSTRACT
OBJECTIVES: This study sought to uncover whether having a gastrointestinal (GI) hospitalist available during weekday daytime hours results in higher-quality medical care compared to care provided by a team of residents. METHODS: Our hospitalist GI team consisted of two gastroenterologists working weekday daytime hours and two physician assistants. The team of conventional care headed by thirteen professors, comprised twelve residents and eight physician assistants. We conducted a retrospective cohort study in South Korea between March 2 and December 9, 2020 The hospitalist team treated 528 patients, while the conventional care team treated 2,335. We assessed the medical parameters of length of stay (LOS), rates of in-hospital mortality, transfer to the intensive care unit, and readmission rate within 30 days. Furthermore, we gathered feedback from nurses working with both teams. RESULTS: The study found that there was no significant difference in LOS between infections (P = 0.422) and other GI diseases like bleeding (P = 0.226). There was no significant difference in the rates of in-hospital mortality (P = 0.865) and transfer to the intensive care unit (P = 0.486) between the two teams. However, the hospitalist team had notably lower readmission rates than the conventional care team (P = 0.002) as well as a lower unscheduled readmission rate (P = 0.046). Furthermore, the survey results indicated that nurses who worked with the hospitalist team had significantly better responses than those who worked with the conventional care team (P < 0.001). CONCLUSIONS: This study indicates that having GI hospitalists work weekday daytime hours improves patient care, and treatment and reduces readmission rates.
Subject(s)
Hospitalists , Humans , Retrospective Studies , Patient Readmission , Quality of Health Care , Length of Stay , Patient Care TeamABSTRACT
BACKGROUND: The number of confirmed cases of individuals with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection increased rapidly due to the Omicron variant. Correctional facilities are vulnerable to infectious diseases, and they introduced rapid antigen tests (RATs) to allow for early detection and rapid response. We aimed to evaluate the diagnostic performance and usefulness of SARS-CoV-2 RATs in newly incarcerated people. MATERIALS AND METHODS: We conducted a cross-sectional study at correctional facilities in Korea from 9 March to 22 May 2022. The study population was newly incarcerated people who were divided into two groups. In one group, 799 paired SARS-CoV-2 RATs and real-time polymerase chain reaction (RT-PCR) were conducted simultaneously in 522 individuals in March 2022. In the other group, 4,034 paired RATs and RT-PCR consecutively in 4,034 participants; only individuals with negative RATs results underwent RT-PCR from April to May 2022. We analyzed data using descriptive statistics and a logistic regression model. RESULTS: Among the 799 specimens in March, RT-PCR was positive in 72 (9.0%), and among the 4,034 specimens in April - May 2022, RT-PCR was positive in 40 (1.0%). Overall, the RATs had a sensitivity of 58.3%, specificity of 100.0%, positive predictive value (PPV) of 100.0%, and negative predictive value (NPV) of 96.0%. Asymptomatic individuals constituted 98.2% of the study group, and symptomatic individuals 1.8%. In asymptomatic cases, the sensitivity of RATs was 52.5%, specificity was 100.0%, PPV was 100.0%, and NPV was 96.3%. In symptomatic cases, the sensitivity of RATs was 84.6%, specificity was 100.0%, PPV was 100.0%, and NPV was 33.3%. Sensitivity (P = 0.034) and NPV (P = 0.004) differed significantly according to the presence and absence of symptoms, and the F1 score was the highest at 0.9 in symptomatic individuals in March. There was a positive linear trend in the proportion of false-negative RATs in newly incarcerated people following the weekly incidence of SARS-CoV-2 (P = 0.033). The best-associated predictors of RATs for SARS-CoV-2 infection involved symptoms, timing of sample collection, and repeat testing. CONCLUSION: Sensitivity and NPV significantly depend on whether symptoms are present, and the percentage of false negatives is correlated with the incidence. Thus, using RATs should be adjusted according to the presence or absence of symptoms and the incidence of SARS-CoV-2 infection in the community. RATs could be a useful screening tool as an effective first-line countermeasure because they can rapidly identify infectious patients and minimize SARS-CoV-2 transmission in correctional facilities.
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Skeletal muscle wasting related to aging or pathological conditions is critically associated with the increased incidence and prevalence of secondary diseases including cardiovascular diseases, metabolic syndromes, and chronic inflammations. Much effort is made to develop agents to enhance muscle metabolism and function. Inonotus obliquus (I. obliquus; IO) is a mushroom popularly called chaga and has been widely employed as a folk medicine for inflammation, cardiovascular diseases, diabetes, and cancer in Eastern Europe and Asia. However, its effect on muscle health has not been explored. Here, we aimed to investigate the beneficial effect of IO extract in muscle regeneration and metabolism. The treatment of IO in C2C12 myoblasts led to increased myogenic differentiation and alleviation of dexamethasone-induced myotube atrophy. Network pharmacological analysis using the identified specific chemical constituents of IO extracts predicted protein kinase B (AKT)-dependent mechanisms to promote myogenesis and muscle regeneration. Consistently, IO treatment resulted in the activation of AKT, which suppressed muscle-specific ubiquitin E3 ligases induced by dexamethasone. IO treatment in mice improved the regeneration of cardiotoxin-injured muscles accompanied by elevated proliferation and differentiation of muscle stem cells. Furthermore, it elevated the mitochondrial content and muscle oxidative metabolism accompanied by the induction of peroxisome proliferator-activated receptor γ coactivator α (PGC-1α). Our current data suggest that IO is a promising natural agent in enhancing muscle regenerative capacity and oxidative metabolism thereby preventing muscle wasting.
Subject(s)
Cardiovascular Diseases , Proto-Oncogene Proteins c-akt , Mice , Animals , Proto-Oncogene Proteins c-akt/metabolism , Cardiovascular Diseases/metabolism , Muscle, Skeletal/metabolism , Muscular Atrophy/etiology , Muscular Atrophy/metabolism , Muscular Atrophy/pathology , Oxidative Stress , Dexamethasone/pharmacology , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolismABSTRACT
Neurological disorders are often debilitating conditions with no cure. The majority of current therapies are palliative rather than disease-modifying; therefore, new strategies for treating neurological disorders are greatly needed. mRNA-based therapeutics have great potential for treating such neurological disorders; however, challenges with delivery have limited their clinical potential. Lipid nanoparticles (LNPs) are a promising delivery vector for the brain, given their safer toxicity profile and higher efficacy. Despite this, very little is known about LNP-mediated delivery of mRNA into the brain. Here, we employ MC3-based LNPs and successfully deliver Cre mRNA and Cas9 mRNA/Ai9 sgRNA to the adult Ai9 mouse brain; greater than half of the entire striatum and hippocampus was found to be penetrated along the rostro-caudal axis by direct intracerebral injections of MC3 LNP mRNAs. MC3 LNP Cre mRNA successfully transfected cells in the striatum (â¼52% efficiency) and hippocampus (â¼49% efficiency). In addition, we demonstrate that MC3 LNP Cas9 mRNA/Ai9 sgRNA edited cells in the striatum (â¼7% efficiency) and hippocampus (â¼3% efficiency). Further analysis demonstrates that MC3 LNPs mediate mRNA delivery to multiple cell types including neurons, astrocytes, and microglia in the brain. Overall, LNP-based mRNA delivery is effective in brain tissue and shows great promise for treating complex neurological disorders.
Subject(s)
Nanoparticles , Nervous System Diseases , Animals , Mice , RNA, Guide, CRISPR-Cas Systems , Brain , RNA, Messenger/genetics , RNA, Small InterferingABSTRACT
Plant nucleotide-binding domain leucine-rich-repeat receptor (NLR) confers disease resistance to various pathogens by recognizing effectors derived from the pathogen. Previous studies have shown that overexpression of the CC domain in several NLRs triggers cell death, implying that the CC domain plays an important role as a signaling module. However, how CC domain transduces immune signals remains largely unknown. A Potyvirus-resistant NLR protein, Pvr4, possesses a CC domain (CCPvr4 ) that induces cell death upon transient overexpression in Nicotiana benthamiana. In this study, loss-of-function mutants were generated by error-prone PCR-based random mutagenesis to understand the molecular mechanisms underlying CCPvr4 -mediated cell death. Cell biology and biochemical studies revealed that M16 and Q52 in the α1 and α2 helices, respectively, are crucial for protein stability, and mutation of these residues disrupts localization to the plasma membrane and oligomerization activity. The increase of the protein stability of these mutants by tagging a green fluorescent protein (GFP) variant led to restoration of cell death-inducing activity and plasma membrane localization. Another mutant, I7E in the very N-terminal region, lost cell death-inducing activity by weakening the interaction with plasma membrane H+ -ATPase compared to CCPvr4 , although the protein remained in the plasma membrane. Moreover, most of the mutated residues are on the outer surface of the funnel shape in the predicted pentameric CCPvr4 , implying that the disordered N-terminal region plays a crucial role in association with PMA as well as targeting to the plasma membrane. This work could provide insights into the molecular mechanisms of cell death induced by NLR immune receptors.
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BACKGROUND: This study aimed to assess the contact tracing outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sub-lineages BA.4, BA.5, and BA.2.75 within Republic of Korea, and to generate foundational data for responding to future novel variants. METHODS: We conducted investigations and contact tracing for 79 confirmed BA.4 cases, 396 confirmed BA.5 cases, and 152 confirmed BA.2.75 cases. These cases were identified through random sampling of both domestically confirmed and imported cases, with the goal of evaluating the pattern of occurrence and transmissibility. RESULTS: We detected 79 instances of Omicron sub-lineage BA.4 across a span of 46 days, 396 instances of Omicron sub-lineage BA.5 in 46 days, and 152 instances of Omicron sub-lineage BA.2.75 over 62 days. One patient with severe illness was confirmed among the BA.5 cases; however, there were no reports of severe illness in the confirmed BA.4 and BA.2.75 cases. The secondary attack risk among household contacts were 19.6% for BA.4, 27.8% for BA.5, and 24.3% for BA.2.75. No statistically significant difference was found between the Omicron sub-lineages. CONCLUSION: BA.2.75 did not demonstrate a higher tendency for transmissibility, disease severity, or secondary attack risk within households when compared to BA.4 and BA.5. We will continue to monitor major SARS-CoV-2 variants, and we plan to enhance the disease control and response systems.
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Importance: Women who undergo surgical hysterectomy before natural menopause may have an earlier increase in hematocrit and storage iron levels than those who continue menstruation, thereby increasing the risk of cardiovascular disease (CVD) at ages younger than usually seen. Examining this issue may provide important implications for women's cardiovascular health to both physicians and patients. Objective: To evaluate the association of hysterectomy with the risk of incident CVD among women before age 50 years. Design, Setting, and Participants: In this Korean population-based cohort study, 135â¯575 women aged 40 to 49 years were evaluated from January 1, 2011, to December 31, 2014. After propensity score matching in covariates including age, socioeconomic status, region, Charlson Comorbidity Index, hypertension, diabetes, dyslipidemia, menopause, menopausal hormone therapy, and adnexal surgery before inclusion, 55â¯539 pairs were included in the hysterectomy and nonhysterectomy groups. Participants were followed up until December 31, 2020. Data analysis was conducted from December 20, 2021, to February 17, 2022. Main Outcomes and Measures: The primary outcome was an incidental CVD, a composite of myocardial infarction, coronary artery revascularization, and stroke. The individual components of the primary outcome were also evaluated. Results: A total of 55 539 pairs were included; median age in the combined groups was 45 (IQR, 42-47) years. During median follow-up periods in the hysterectomy group of 7.9 (IQR, 6.8-8.9) years and nonhysterectomy group of 7.9 (IQR, 6.8-8.8) years, the incidence of CVD was 115 per 100â¯000 person-years for the hysterectomy group and 96 per 100â¯000 person-years for the nonhysterectomy group. After adjusting for confounding factors, the hysterectomy group had an increased risk of CVD compared with the nonhysterectomy group (hazard ratio [HR], 1.25; 95% CI, 1.09-1.44). The incidences of myocardial infarction and coronary artery revascularization were comparable between the groups, whereas the risk of stroke was significantly higher in the hysterectomy group (HR, 1.31; 95% CI, 1.12-1.53). Even after excluding women who underwent oophorectomy, the hysterectomy group had higher risks of CVD (HR, 1.24; 95% CI, 1.06-1.44). Conclusions and Relevance: The findings of this cohort study suggest early menopause owing to hysterectomy was associated with increased risks for a composite of CVD, particularly stroke.
Subject(s)
Cardiovascular Diseases , Myocardial Infarction , Stroke , Humans , Female , Adult , Middle Aged , Cohort Studies , Hysterectomy , Republic of KoreaABSTRACT
The introduction of bacteria into slaughterhouses can lead to microbial contamination in carcasses during slaughter, and the initial level of bacteria in carcasses is important because it directly affects spoilage and the shelf life. This study was conducted to investigate the microbiological quality, and the prevalence of foodborne pathogens in 200 carcasses from 20 pig slaughterhouses across Korea. Distribution of microbial counts were significantly higher for aerobic bacteria at 3.01-4.00 log10 CFU/cm2 (42.0%) and 2.01-3.00 log10 CFU/cm2 (28.5%), whereas most of Escherichia coli showed the counts under 1.00 log10 CFU/cm2 (87.0%) (P < 0.05). The most common pathogen isolated from 200 carcasses was Staphylococcus aureus (11.5%), followed by Yersinia enterocolitica (7.0%). In total, 17 S. aureus isolates from four slaughterhouses were divided into six pulsotypes and seven spa types, and showed the same or different types depending on the slaughterhouses. Interestingly, isolates from two slaughterhouses carried only LukED associated with the promotion of bacterial virulence, whereas, isolates from two other slaughterhouses carried one or more toxin genes associated with enterotoxins including sen. In total, 14 Y. enterocolitica isolates from six slaughterhouses were divided into nine pulsotypes, 13 isolates belonging to biotype 1A or 2 carried only ystB, whereas one isolate belonging to bio-serotype 4/O:3 carried both ail and ystA. This is the first study to investigate microbial quality and the prevalence of foodborne pathogens in carcasses from slaughterhouses nationally, and the findings support the need for ongoing slaughterhouse monitoring to improve the microbiological safety of pig carcasses.
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The DAMA/LIBRA collaboration has reported the observation of an annual modulation in the event rate that has been attributed to dark matter interactions over the last two decades. However, even though tremendous efforts to detect similar dark matter interactions were pursued, no definitive evidence has been observed to corroborate the DAMA/LIBRA signal. Many studies assuming various dark matter models have attempted to reconcile DAMA/LIBRA's modulation signals and null results from other experiments, however no clear conclusion can be drawn. Apart from the dark matter hypothesis, several studies have examined the possibility that the modulation is induced by variations in detector's environment or their specific analysis methods. In particular, a recent study presents a possible cause of the annual modulation from an analysis method adopted by the DAMA/LIBRA experiment in which the observed annual modulation could be reproduced by a slowly varying time-dependent background. Here, we study the COSINE-100 data using an analysis method similar to the one adopted by the DAMA/LIBRA experiment and observe a significant annual modulation, however the modulation phase is almost opposite to that of the DAMA/LIBRA data. Assuming the same background composition for COSINE-100 and DAMA/LIBRA, simulated experiments for the DAMA/LIBRA without dark matter signals also provide significant annual modulation with an amplitude similar to DAMA/LIBRA with opposite phase. Even though this observation does not directly explain the DAMA/LIBRA results directly, this interesting phenomenon motivates more profound studies of the time-dependent DAMA/LIBRA background data.
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Phosphorylation state-dependent interactions of the phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS) components with transcription factors play a key role in carbon catabolite repression (CCR) by glucose in bacteria. Glucose inhibits the PTS-dependent transport of fructose and is preferred over fructose in Vibrio cholerae, but the mechanism is unknown. We have recently shown that, contrary to Escherichia coli, the fructose-dependent transcriptional regulator FruR acts as an activator of the fru operon in V. cholerae and binding of the FruR-fructose 1-phosphate (F1P) complex to an operator facilitates RNA polymerase (RNAP) binding to the fru promoter. Here we show that, in the presence of glucose, dephosphorylated HPr, a general PTS component, binds to FruR. Whereas HPr does not affect DNA-binding affinity of FruR, regardless of the presence of F1P, it prevents the FruR-F1P complex from facilitating the binding of RNAP to the fru promoter. Structural and biochemical analyses of the FruR-HPr complex identify key residues responsible for the V. cholerae-specific FruR-HPr interaction not observed in E. coli. Finally, we reveal how the dephosphorylated HPr interacts with FruR in V. cholerae, whereas the phosphorylated HPr binds to CcpA, which is a global regulator of CCR in Bacillus subtilis and shows structural similarity to FruR.
Subject(s)
Bacterial Proteins , Repressor Proteins , Vibrio cholerae , Bacterial Proteins/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Fructose/metabolism , Gene Expression Regulation, Bacterial , Glucose , Operon , Phosphorylation , Repressor Proteins/metabolism , Vibrio cholerae/metabolism , DNA-Directed RNA Polymerases/metabolismABSTRACT
Pathogen effectors can suppress various plant immune responses, suggesting that they have multiple targets in the host. To understand the mechanisms underlying plasma membrane-associated and effector-mediated immunity, we screened the Phytophthora capsici RxLR cell death-inducer suppressing immune system (CRISIS). We found that the cell death induced by the CRISIS2 effector in Nicotiana benthamiana was inhibited by the irreversible plasma membrane H+-ATPase (PMA) activator fusicoccin. Biochemical and gene-silencing analyses revealed that CRISIS2 physically and functionally associated with PMAs and induced host cell death independent of immune receptors. CRISIS2 induced apoplastic alkalization by suppressing PMA activity via its association with the C-terminal regulatory domain. In planta expression of CRISIS2 significantly enhanced the virulence of P. capsici, whereas host-induced gene-silencing of CRISIS2 compromised the disease symptoms and the biomass of the pathogen. Thus, our study has identified a novel RxLR effector that plays multiple roles in the suppression of plant defense and in the induction of cell death to support the pathogen hemibiotrophic life cycle in the host plant.
Subject(s)
Phytophthora infestans , Cell Death , Virulence , Nicotiana/genetics , Cell Membrane , Adenosine Triphosphatases , Plant Diseases , Plant Immunity/physiologyABSTRACT
Social learning in the forms of imitative and contagious behaviors are essential for learning abilities and social interaction. However, children with neurodevelopmental disorders and intellectual disabilities show impairments in these behaviors, which profoundly affect their communication skills and cognitive functions. Although these deficits are well studied in humans, pre-clinical animal model assessments of imitative and contagious behavioral deficits are limited. Here, we first define various forms of social learning as well as their developmental and evolutionary significance in humans. We also explore the impact of imitative and contagious behavioral deficits in several neurodevelopmental disorders associated with autistic-like symptoms. Second, we highlight imitative and contagious behaviors observed in nonhuman primates and other social animals commonly used as models for neurodevelopmental disorders. Lastly, we conceptualize these behaviors in the contexts of mirror neuron activity, learning, and empathy, which are highly debated topics. Taken together, this review furthers the understanding of imitative and contagious behaviors. We hope to prompt and guide future behavioral studies in animal models of neurodevelopmental disorders.