Summary Background In 2015, a large outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) infection occurred following a single patient exposure in an emergency room at the Samsung ...Medical Center, a tertiary-care hospital in Seoul, South Korea. We aimed to investigate the epidemiology of MERS-CoV outbreak in our hospital. Methods We identified all patients and health-care workers who had been in the emergency room with the index case between May 27 and May 29, 2015. Patients were categorised on the basis of their exposure in the emergency room: in the same zone as the index case (group A), in different zones except for overlap at the registration area or the radiology suite (group B), and in different zones (group C). We documented cases of MERS-CoV infection, confirmed by real-time PCR testing of sputum samples. We analysed attack rates, incubation periods of the virus, and risk factors for transmission. Findings 675 patients and 218 health-care workers were identified as contacts. MERS-CoV infection was confirmed in 82 individuals (33 patients, eight health-care workers, and 41 visitors). The attack rate was highest in group A (20% 23/117 vs 5% 3/58 in group B vs 1% 4/500 in group C; p<0·0001), and was 2% (5/218) in health-care workers. After excluding nine cases (because of inability to determine the date of symptom onset in six cases and lack of data from three visitors), the median incubation period was 7 days (range 2–17, IQR 5–10). The median incubation period was significantly shorter in group A than in group C (5 days IQR 4–8 vs 11 days 6–12; p<0·0001). There were no confirmed cases in patients and visitors who visited the emergency room on May 29 and who were exposed only to potentially contaminated environment without direct contact with the index case. The main risk factor for transmission of MERS-CoV was the location of exposure. Interpretation Our results showed increased transmission potential of MERS-CoV from a single patient in an overcrowded emergency room and provide compelling evidence that health-care facilities worldwide need to be prepared for emerging infectious diseases. Funding None.
Although a variety of stretchable strain sensors based on electrical percolation have been reported, stretchable sensors detecting low strains have been rarely demonstrated. This is because large ...stretchability of a strain sensor conflicts with high strain resolution at low strains. Here, the electrical percolation into 2D is confined and a strain sensor that is highly sensitive at low strains and simultaneously highly stretchable is presented. The 2D confinement of the electrical percolation is accomplished by a close‐packed monolayer assembly of conductive microparticles (MPs) on an elastomer substrate. The current profiles of the MP monolayer at low strains are in situ visualized using conductive atomic force microscopy. When the lattice of the MP monolayer is aligned vertically to the strain direction, the resistance is highly sensitive to low‐strain deformations (ε = 0 – 0.05), but the sensor has reasonable stretchability (ε = 0.3). The simultaneous achievement of the high sensitivity at low strains and the reasonable stretchability is explained by the relationship between the strain‐dependent current profile and the relative position changes of the MPs. A high‐precision pulse sensor clearly showing the representative peaks is demonstrated.
Here, 2D electrical percolation in a monolayer of close‐packed conductive microparticles is analyzed and a correlation between the electrical changes and the lattice orientation and morphology is established. A stretchable sensor with high sensitivity in small strains is demonstrated, which clearly presents the representative three peaks of the heart pulse (P1, P2, P3).
Summary Background After the 2015 Middle East respiratory syndrome (MERS) outbreak in Korea, prediction of pneumonia development and progression to respiratory failure was emphasized in control of ...MERS outbreak. Methods MERS-CoV infected patients who were managed in a tertiary care center during the 2015 Korean MERS outbreak were reviewed. To analyze predictive factors for pneumonia development and progression to respiratory failure, we evaluated clinical variables measured within three days from symptom onset. Results A total of 45 patients were included in the study: 13 patients (28.9%) did not develop pneumonia, 19 developed pneumonia without respiratory failure (42.2%), and 13 progressed to respiratory failures (28.9%). The identified predictive factors for pneumonia development included age ≥45 years, fever ≥37.5 °C, thrombocytopenia, lymphopenia, CRP ≥ 2 mg/dL, and a threshold cycle value of PCR less than 28.5. For respiratory failure, the indicators included male, hypertension, low albumin concentration, thrombocytopenia, lymphopenia, and CRP ≥ 4 mg/dL (all P < 0.05). With ≥ two predictive factors for pneumonia development, 100% of patients developed pneumonia. Patients lacking the predictive factors did not progress to respiratory failure. Conclusion For successful control of MERS outbreak, MERS-CoV infected patients with ≥ two predictive factors should be intensively managed from the initial presentation.
Stomata are epidermal openings that facilitate plant-atmosphere gas exchange during photosynthesis, respiration, and water evaporation. Stomatal differentiation and patterning are spatially and ...temporally regulated by the master regulators SPEECHLESS (SPCH), MUTE, and FAMA, which constitute a central gene regulatory network along with Inducer of CBF Expression (ICE) transcription factors for this developmental process. Stomatal development is also profoundly influenced by environmental conditions, such as light, temperature, and humidity. Light induces stomatal development, and various photoreceptors modulate this response. However, it is unknown how light is functionally linked with the master regulatory network. Here, we demonstrate that, under dark conditions, the E3 ubiquitin ligase CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1) degrades ICE proteins through ubiquitination pathways in leaf abaxial epidermal cells in Arabidopsis thaliana. Accordingly, the ICE proteins accumulate in the nuclei of leaf abaxial epidermal cells in COP1-defective mutants, which constitutively produce stomata. Notably, light in the blue, red, and far-red wavelength ranges suppresses the COP1-mediated degradation of the ICE proteins to induce stomatal development. These observations indicate that light is directly linked with the ICE-directed signaling module, via the COP1-mediated protein surveillance system, in the modulation of stomatal development.
In 2015, a large outbreak of Middle East respiratory syndrome (MERS) occurred in the Republic of Korea. Half of the cases were associated with a tertiary care university hospital.
To document the ...outbreak and successful control measures.
Descriptive study.
A 1950-bed tertiary care university hospital.
92 patients with laboratory-confirmed MERS and 9793 exposed persons.
Description of the outbreak, including a timeline, and evaluation of the effectiveness of the control measures.
During the outbreak, 92 laboratory-confirmed MERS cases were associated with a large tertiary care hospital, 82 of which originated from unprotected exposure to 1 secondary patient. Contact tracing and monitoring exposed patients and assigned health care workers were at the core of the control measures in the outbreak. Nontargeted screening measures, including body temperature screening among employees and visitors at hospital gates, monitoring patients for MERS-related symptoms, chest radiographic screening, and employee symptom monitoring, did not detect additional patients with MERS without existing transmission links. All in-hospital transmissions originated from 3 patients with MERS who also had pneumonia and productive cough.
This was a retrospective single-center study. Statistical analysis could not be done. Because this MERS outbreak originated from a superspreader, effective control measures could differ in endemic areas or in other settings.
Control strategies for MERS outbreaks should focus on tracing contacts of persons with epidemiologic links. Adjusting levels of quarantine and personal protective equipment according to the assumed infectivity of each patient with MERS may be appropriate.
Samsung Biomedical Research Institute.
Organic solid electrolytes offer an effective route for safe and high‐energy‐density all‐solid‐state Li metal batteries. However, it remains a challenge to devise a new strategy to promote the ...dissociation of strong ion pairs and the transport of ionic components in organic solid electrolytes. Herein, a zwitterionic covalent organic framework (Zwitt‐COF) with well‐defined chemical and pore structures is prepared as a solid electrolyte capable of accelerating the dissociation and transport of Li ions. The Zwitt‐COF solid electrolyte exhibits a high room‐temperature ionic conductivity of 1.65 × 10−4 S cm−1 with a wide electrochemical stability window. Besides, the Zwitt‐COF solid electrolyte displays stable Li plating/stripping behavior via effective inhibition of the formation of Li dendrites and dead Li, leading to superior long‐term cycle performance with retention of 99% discharge capacity and 98% Coulombic efficiency in an all‐solid‐state Li‐metal battery. Theoretical simulations reveal that the incorporation of zwitterionic groups into COF can facilitate the dissociation of strong ion pairs and reconstruct the AA‐stacking configuration by dissociative adsorption of Li+ ions on Zwitt‐COF producing linear hexagonal ion channels in the Zwitt‐COF solid electrolyte. This strategy based on Zwitt‐COF can provide an alternative way to construct various solid‐state Li batteries.
A zwitterionic covalent organic framework (Zwitt‐COF) is developed as a solid electrolyte for all‐solid‐state Li‐metal batteries. The Zwitt‐COF solid electrolyte exhibits a high room‐temperature ionic conductivity with a wide electrochemical window, leading to superior long‐term cycle performance in the battery. Theoretical simulations reveal that Zwitt‐COF promotes the dissociation of Li‐ion pairs and provides ion channels for effective Li+ transport.
Matter–light interaction is at the center of diverse research fields from quantum optics to condensed matter physics, opening new fields like laser physics. A magnetic exciton is one such rare ...example found in magnetic insulators. However, it is relatively rare to observe that external variables control matter‐light interaction. Here, it is reported that the broken inversion symmetry of multiferroicity can act as an external knob enabling magnetic excitons in the van der Waals antiferromagnet NiI2. It is further discovered that this magnetic exciton arises from a transition between Zhang–Rice‐triplet and Zhang–Rice‐singlet fundamentally quantum‐entangled states. This quantum entanglement produces an ultrasharp optical exciton peak at 1.384 eV with a 5 meV linewidth. The work demonstrates that NiI2 is 2D magnetically ordered with an intrinsically quantum‐entangled ground state.
Quantum‐entangled magnetic excitons develop in a triangular multiferroic NiI2 when it goes through a second phase transition at low temperatures. In this graph of optical absorption data, the bright regions indicate where two exciton‐related peaks appear below the second magnetic phase transition as indicated by the dashed line. The many‐body calculations show that this exciton arises from a transition between two quantum‐entangled states of Zhang–Rice triplet and Zhang–Rice singlet states.
The effects of convalescent plasma (CP) infusion, one of the treatment options for severe Middle East respiratory syndrome coronavirus (MERS-CoV) infections, have not yet been evaluated.
Serological ...responses of CP-infused MERS patients during the 2015 Korean MERS outbreak at a tertiary care centre were evaluated. Serological activity was evaluated with anti-MERS-CoV enzyme-linked immunosorbent assay (ELISA) immunoglobulin (Ig)G, ELISA IgA, immunofluorescence assay IgM and plaque reduction neutralization test (PRNT). Donor plasma and one or two recipient's serum samples per week of illness including one taken the day after each CP infusion were evaluated. For sensitivity and specificity analysis of ELISA IgG in predicting neutralization activity, a data set of 138 previously evaluated MERS-CoV-infected patients was used.
Three of thirteen MERS patients with respiratory failure received four CP infusions from convalesced MERS-CoV-infected patients, and only two of them showed neutralizing activity. Donor plasma with a PRNT titre 1:80 demonstrated meaningful serological response after CP infusion, while that with a PRNT titre 1:40 did not. ELISA IgG predicted neutralization activity of a PRNT titre ≥1:80 with more than 95% specificity at a cutoff optical density (OD) ratio of 1.6, and with 100% specificity at an OD ratio of 1.9.
For effective CP infusion in MERS, donor plasma with a neutralization activity of a PRNT titre ≥1:80 should be used. ELISA IgG could substitute for the neutralization test in resource-limited situations.
Summary
miR156 and its target SQUAMOSA PROMOTER BINDING PROTEIN‐LIKE (SPL) genes constitute an endogenous flowering pathway in Arabidopsis. The SPL genes are regulated post‐transcriptionally by ...miR156, and incorporate endogenous aging signals into floral gene networks. Intriguingly, the SPL genes are also regulated transcriptionally by FLOWERING LOCUS T (FT)‐mediated photoperiod signals. However, it is unknown how photoperiod regulates the SPL genes. Here, we show that SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) and FT regulate the SPL3, SPL4 and SPL5 genes by directly binding to the gene promoters in response to photoperiod signals. Notably, the SOC1 regulation of the SPL genes, termed the SOC1‐SPL module, also mediates gibberellic acid (GA) signals to promote flowering under non‐inductive short days (SDs). Under SDs, the inductive effects of GA on the SPL genes disappeared in the soc1‐2 mutant, and the flowering of SPL3‐overexpressing transgenic plants (35S:SPL3) was less sensitive to GA. In addition, the 35S:SPL3 × soc1‐2 plants flowered much earlier than the soc1‐2 mutant, supporting SOC1 regulation of the SPL genes. Our observations indicate that the SOC1‐SPL module serves as a molecular link that integrates photoperiod and GA signals to promote flowering in Arabidopsis.
Memory T cell responses have been demonstrated in COVID-19 convalescents, but ex vivo phenotypes of SARS-CoV-2-specific T cells have been unclear. We detected SARS-CoV-2-specific CD8+ T cells by MHC ...class I multimer staining and examined their phenotypes and functions in acute and convalescent COVID-19. Multimer+ cells exhibited early differentiated effector-memory phenotypes in the early convalescent phase. The frequency of stem-like memory cells was increased among multimer+ cells in the late convalescent phase. Cytokine secretion assays combined with MHC class I multimer staining revealed that the proportion of interferon-γ (IFN-γ)-producing cells was significantly lower among SARS-CoV-2-specific CD8+ T cells than those specific to influenza A virus. Importantly, the proportion of IFN-γ-producing cells was higher in PD-1+ cells than PD-1− cells among multimer+ cells, indicating that PD-1-expressing, SARS-CoV-2-specific CD8+ T cells are not exhausted, but functional. Our current findings provide information for understanding of SARS-CoV-2-specific CD8+ T cells elicited by infection or vaccination.
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•SARS-CoV-2-specific CD8+ T cells are effector memory cells in convalescents•CCR7+CD45RA+ cells are increased among SARS-CoV-2-specific cells in the late phase•SARS-CoV-2-specific CD8+ T cells have fewer IFN-γ+ cells than flu-specific cells•PD-1-expressing SARS-CoV-2-specific CD8+ T cells are not exhausted but functional
T cell responses have been demonstrated in COVID-19 patients, but ex vivo phenotypes and functions of SARS-CoV-2-specific T cells remain unclear. Rha et al. examined SARS-CoV-2-specific CD8+ T cells in acute and convalescent COVID-19 patients using MHC class I multimers, finding that PD-1-expressing SARS-CoV-2-specific CD8+ T cells are not exhausted but functional.
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