The Omicron variant is rapidly becoming the dominant SARS-CoV-2 virus circulating globally. It is important to define reductions in virus neutralizing activity in the serum of convalescent or ...vaccinated individuals to understand potential loss of protection against infection by Omicron. We previously established that a 50% plaque reduction neutralization antibody titer (PRNT
) ≥25.6 in our live virus assay corresponded to the threshold for 50% protection from infection against wild-type (WT) SARS-CoV-2. Here we show markedly reduced serum antibody titers against the Omicron variant (geometric mean titer (GMT) < 10) compared to WT virus 3-5 weeks after two doses of BNT162b2 (GMT = 218.8) or CoronaVac vaccine (GMT = 32.5). A BNT162b2 booster dose elicited Omicron PRNT
titers ≥25.6 in 88% of individuals (22 of 25) who previously received 2 doses of BNT162b2 and 80% of individuals (24 of 30) who previously received CoronaVac. However, few (3%) previously infected individuals (1 of 30) or those vaccinated with three doses of CoronaVac (1 of 30) met this threshold. Our findings suggest that countries primarily using CoronaVac vaccines should consider messenger RNA vaccine boosters in response to the spread of Omicron. Studies evaluating the effectiveness of different vaccines against the Omicron variant are urgently needed.
The coronavirus disease 2019 (COVID-19) pandemic has resulted in millions of patients infected worldwide and indirectly affecting even more individuals through disruption of daily living. Long-term ...adverse outcomes have been reported with similar diseases from other coronaviruses, namely Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). Emerging evidence suggests that COVID-19 adversely affects different systems in the human body. This review summarizes the current evidence on the short-term adverse health outcomes and assesses the risk of potential long-term adverse outcomes of COVID-19. Major adverse outcomes were found to affect different body systems: immune system (including but not limited to Guillain-Barré syndrome and paediatric inflammatory multisystem syndrome), respiratory system (lung fibrosis and pulmonary thromboembolism), cardiovascular system (cardiomyopathy and coagulopathy), neurological system (sensory dysfunction and stroke), as well as cutaneous and gastrointestinal manifestations, impaired hepatic and renal function. Mental health in patients with COVID-19 was also found to be adversely affected. The burden of caring for COVID-19 survivors is likely to be huge. Therefore, it is important for policy makers to develop comprehensive strategies in providing resources and capacity in the healthcare system. Future epidemiological studies are needed to further investigate the long-term impact on COVID-19 survivors.
Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects gastrointestinal tissues, little is known about the roles of gut commensal microbes in susceptibility to and severity of ...infection. We investigated changes in fecal microbiomes of patients with SARS-CoV-2 infection during hospitalization and associations with severity and fecal shedding of virus.
We performed shotgun metagenomic sequencing analyses of fecal samples from 15 patients with Coronavirus Disease 2019 (COVID-19) in Hong Kong, from February 5 through March 17, 2020. Fecal samples were collected 2 or 3 times per week from time of hospitalization until discharge; disease was categorized as mild (no radiographic evidence of pneumonia), moderate (pneumonia was present), severe (respiratory rate ≥30/min, or oxygen saturation ≤93% when breathing ambient air), or critical (respiratory failure requiring mechanical ventilation, shock, or organ failure requiring intensive care). We compared microbiome data with those from 6 subjects with community-acquired pneumonia and 15 healthy individuals (controls). We assessed gut microbiome profiles in association with disease severity and changes in fecal shedding of SARS-CoV-2.
Patients with COVID-19 had significant alterations in fecal microbiomes compared with controls, characterized by enrichment of opportunistic pathogens and depletion of beneficial commensals, at time of hospitalization and at all timepoints during hospitalization. Depleted symbionts and gut dysbiosis persisted even after clearance of SARS-CoV-2 (determined from throat swabs) and resolution of respiratory symptoms. The baseline abundance of Coprobacillus, Clostridium ramosum, and Clostridium hathewayi correlated with COVID-19 severity; there was an inverse correlation between abundance of Faecalibacterium prausnitzii (an anti-inflammatory bacterium) and disease severity. Over the course of hospitalization, Bacteroides dorei, Bacteroides thetaiotaomicron, Bacteroides massiliensis, and Bacteroides ovatus, which downregulate expression of angiotensin-converting enzyme 2 (ACE2) in murine gut, correlated inversely with SARS-CoV-2 load in fecal samples from patients.
In a pilot study of 15 patients with COVID-19, we found persistent alterations in the fecal microbiome during the time of hospitalization, compared with controls. Fecal microbiota alterations were associated with fecal levels of SARS-CoV-2 and COVID-19 severity. Strategies to alter the intestinal microbiota might reduce disease severity.
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Plastic crystal neopentylglycol (NPG) exhibits colossal barocaloric effects (BCEs) with record-high entropy changes, offering exciting prospects for the field of solid-state cooling through the ...application of moderate pressures. Here, we show that the intermolecular hydrogen bond plays a key role in the orientational order of NPG molecules, while its broken due to thermal perturbation prominently weakens the activation barrier of orientational disorder. The analysis of hydrogen bond strength, rotational entropy free energy and entropy changes provides insightful understanding of BCEs in order-disorder transition. External pressure reduce the hydsrogen bond length and enhance the activation barrier of orientational disorder, which serves as a route of varying intermolecular interaction to tune the order-disorder transition. Our work provides atomic-scale insights on the orientational order-disorder transition of NPG as the prototypical plastic crystal with BCEs, which is helpful to achieve superior caloric materials by molecular designing in the near future.
Magnetic fields are ubiquitous in the Universe. The energy density of these fields is typically comparable to the energy density of the fluid motions of the plasma in which they are embedded, making ...magnetic fields essential players in the dynamics of the luminous matter. The standard theoretical model for the origin of these strong magnetic fields is through the amplification of tiny seed fields via turbulent dynamo to the level consistent with current observations. However, experimental demonstration of the turbulent dynamo mechanism has remained elusive, since it requires plasma conditions that are extremely hard to re-create in terrestrial laboratories. Here we demonstrate, using laser-produced colliding plasma flows, that turbulence is indeed capable of rapidly amplifying seed fields to near equipartition with the turbulent fluid motions. These results support the notion that turbulent dynamo is a viable mechanism responsible for the observed present-day magnetization.
Although COVID-19 is primarily a respiratory illness, there is mounting evidence suggesting that the GI tract is involved in this disease. We investigated whether the gut microbiome is linked to ...disease severity in patients with COVID-19, and whether perturbations in microbiome composition, if any, resolve with clearance of the SARS-CoV-2 virus.
In this two-hospital cohort study, we obtained blood, stool and patient records from 100 patients with laboratory-confirmed SARS-CoV-2 infection. Serial stool samples were collected from 27 of the 100 patients up to 30 days after clearance of SARS-CoV-2. Gut microbiome compositions were characterised by shotgun sequencing total DNA extracted from stools. Concentrations of inflammatory cytokines and blood markers were measured from plasma.
Gut microbiome composition was significantly altered in patients with COVID-19 compared with non-COVID-19 individuals irrespective of whether patients had received medication (p<0.01). Several gut commensals with known immunomodulatory potential such as
,
and bifidobacteria were underrepresented in patients and remained low in samples collected up to 30 days after disease resolution. Moreover, this perturbed composition exhibited stratification with disease severity concordant with elevated concentrations of inflammatory cytokines and blood markers such as C reactive protein, lactate dehydrogenase, aspartate aminotransferase and gamma-glutamyl transferase.
Associations between gut microbiota composition, levels of cytokines and inflammatory markers in patients with COVID-19 suggest that the gut microbiome is involved in the magnitude of COVID-19 severity possibly via modulating host immune responses. Furthermore, the gut microbiota dysbiosis after disease resolution could contribute to persistent symptoms, highlighting a need to understand how gut microorganisms are involved in inflammation and COVID-19.
BACKGROUND: Selenium is an essential trace element with antioxidant property. Decreased serum selenium concentration with aging had been found in previous report. In this study, we aim to investigate ...the association between serum selenium and the inflammatory cytokine interleukin-6 in the elderly living in long-term care facilities in Taiwan. MATERIALS AND METHODS: A total of 336 subjects aged 65 years and older (range of age: 65–101 years) were recruited from eight long-term care facilities in 2002–2003. Baseline characteristics, anthropometric indices, and biochemical data were obtained. Selenium deficiency was defined as serum selenium concentration < 80 μg/L. Multiple logistic and linear regression analyses were used to examine the relationships between selenium deficiency and interleukin-6 (divided into quartiles). RESULTS: The prevalence of selenium deficiency was 35.6% in men and 43.2% in women, respectively. After adjusting for potential confounders using multiple logistic regression analysis, interleukin-6 quartiles were significantly associated with selenium deficiency. Compared to the interleukin-6 quartile I, the adjusted odds ratios of having selenium deficiency for interleukin-6 quartile II, III, IV were 1.00(0.50∼2.01), 1.24 (0.62∼2.50), and 2.35(1.15‖4.83), respectively. The increasing odds ratios for selenium deficiency in higher interleukin-6 quartiles revealed dose-response effects (p < 0.05). Moreover, multiple linear regression analysis showed that serum selenium was significantly inversely associated with interleukin-6 after adjusting for potential confounders. CONCLUSIONS: Serum selenium was inversely associated with inflammatory cytokine interleukin-6 among elderly living in long-term care facilities in Taiwan. Monitoring serum selenium should be considered in these institutionalized elderly.
Abstract
Context
Previous studies suggested a potential link of maternal thyroid dysfunction with adverse neurocognitive outcomes and impaired development of internal organs in offspring.
Objective
...To review the association between maternal thyroid dysfunction and the risk of adverse outcomes in offspring.
Data Sources
PubMed, EMBASE, and Cochrane Library.
Study Selections
Eligible studies reported the association between maternal thyroid hormone function and the risk of adverse outcomes in their children.
Data Extraction
Reviewers extracted data on study characteristics and results independently.
Data Synthesis
Estimates were pooled and reported as odds ratio (OR) with 95% confidence interval (CI). I2 tests were applied to assess the heterogeneity across studies.
Results
We identified 29 eligible articles and found an association between maternal hyperthyroidism and attention deficit hyperactivity disorder (ADHD) (OR: 1.18, 95% CI: 1.04-1.34, I2 = 0%) and epilepsy (OR: 1.19, 95% CI: 1.08-1.31, I2 = 0%) in offspring; as well as an association of maternal hypothyroidism with increased risk of ADHD (OR: 1.14, 95% CI: 1.03-1.26, I2 = 25%), autism spectrum disorder (OR: 1.41, 95% CI: 1.05-1.90, I2 = 63%), and epilepsy (OR: 1.21, 95% CI: 1.06-1.39, I2 = 0%) in offspring.
Conclusion
Routine measurement and timely treatment on thyroid function should be considered for pregnant women.
Intense lasers can accelerate electrons to very high energy over a short distance. Such compact accelerators have several potential applications including fast ignition, high energy physics, and ...radiography. Among the various schemes of laser-based electron acceleration, vacuum laser acceleration has the merits of super-high acceleration gradient and great simplicity. Yet its realization has been difficult because injecting free electrons into the fast-oscillating laser field is not trivial. Here we demonstrate free-electron injection and subsequent vacuum laser acceleration of electrons up to 20 MeV using the relativistic transparency effect. When a high-contrast intense laser drives a thin solid foil, electrons from the dense opaque plasma are first accelerated to near-light speed by the standing laser wave in front of the solid foil and subsequently injected into the transmitted laser field as the opaque plasma becomes relativistically transparent. It is possible to further optimize the electron injection/acceleration by manipulating the laser polarization, incident angle, and temporal pulse shaping. Our result also sheds light on the fundamental relativistic transparency process, crucial for producing secondary particle and light sources.
The optical design and performance of the recently opened 13A biological small‐angle X‐ray scattering (SAXS) beamline at the 3.0 GeV Taiwan Photon Source of the National Synchrotron Radiation ...Research Center are reported. The beamline is designed for studies of biological structures and kinetics in a wide range of length and time scales, from angstrom to micrometre and from microsecond to minutes. A 4 m IU24 undulator of the beamline provides high‐flux X‐rays in the energy range 4.0–23.0 keV. MoB4C double‐multilayer and Si(111) double‐crystal monochromators (DMM/DCM) are combined on the same rotating platform for a smooth rotation transition from a high‐flux beam of ∼4 × 1014 photons s−1 to a high‐energy‐resolution beam of ΔE/E ≃ 1.5 × 10−4; both modes share a constant beam exit. With a set of Kirkpatrick–Baez (KB) mirrors, the X‐ray beam is focused to the farthest SAXS detector position, 52 m from the source. A downstream four‐bounce crystal collimator, comprising two sets of Si(311) double crystals arranged in a dispersive configuration, optionally collimate the DCM (vertically diffracted) beam in the horizontal direction for ultra‐SAXS with a minimum scattering vector q down to 0.0004 Å−1, which allows resolving ordered d‐spacing up to 1 µm. A microbeam, of 10–50 µm beam size, is tailored by a combined set of high‐heat‐load slits followed by micrometre‐precision slits situated at the front‐end 15.5 m position. The second set of KB mirrors then focus the beam to the 40 m sample position, with a demagnification ratio of ∼1.5. A detecting system comprising two in‐vacuum X‐ray pixel detectors is installed to perform synchronized small‐ and wide‐angle X‐ray scattering data collections. The observed beamline performance proves the feasibility of having compound features of high flux, microbeam and ultra‐SAXS in one beamline.
The optical design and performance of the BioSAXS beamline at the Taiwan Photon Source are reported
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