The clinical features and immune responses of asymptomatic individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have not been well described. We studied 37 ...asymptomatic individuals in the Wanzhou District who were diagnosed with RT-PCR-confirmed SARS-CoV-2 infections but without any relevant clinical symptoms in the preceding 14 d and during hospitalization. Asymptomatic individuals were admitted to the government-designated Wanzhou People's Hospital for centralized isolation in accordance with policy
. The median duration of viral shedding in the asymptomatic group was 19 d (interquartile range (IQR), 15-26 d). The asymptomatic group had a significantly longer duration of viral shedding than the symptomatic group (log-rank P = 0.028). The virus-specific IgG levels in the asymptomatic group (median S/CO, 3.4; IQR, 1.6-10.7) were significantly lower (P = 0.005) relative to the symptomatic group (median S/CO, 20.5; IQR, 5.8-38.2) in the acute phase. Of asymptomatic individuals, 93.3% (28/30) and 81.1% (30/37) had reduction in IgG and neutralizing antibody levels, respectively, during the early convalescent phase, as compared to 96.8% (30/31) and 62.2% (23/37) of symptomatic patients. Forty percent of asymptomatic individuals became seronegative and 12.9% of the symptomatic group became negative for IgG in the early convalescent phase. In addition, asymptomatic individuals exhibited lower levels of 18 pro- and anti-inflammatory cytokines. These data suggest that asymptomatic individuals had a weaker immune response to SARS-CoV-2 infection. The reduction in IgG and neutralizing antibody levels in the early convalescent phase might have implications for immunity strategy and serological surveys.
The Coronavirus Disease 2019 (COVID-19) pandemic continues to have a devastating effect on the health and well-being of the global population. A critical step in the fight against COVID-19 is ...effective screening of infected patients, with one of the key screening approaches being radiology examination using chest radiography. It was found in early studies that patients present abnormalities in chest radiography images that are characteristic of those infected with COVID-19. Motivated by this and inspired by the open source efforts of the research community, in this study we introduce COVID-Net, a deep convolutional neural network design tailored for the detection of COVID-19 cases from chest X-ray (CXR) images that is open source and available to the general public. To the best of the authors' knowledge, COVID-Net is one of the first open source network designs for COVID-19 detection from CXR images at the time of initial release. We also introduce COVIDx, an open access benchmark dataset that we generated comprising of 13,975 CXR images across 13,870 patient patient cases, with the largest number of publicly available COVID-19 positive cases to the best of the authors' knowledge. Furthermore, we investigate how COVID-Net makes predictions using an explainability method in an attempt to not only gain deeper insights into critical factors associated with COVID cases, which can aid clinicians in improved screening, but also audit COVID-Net in a responsible and transparent manner to validate that it is making decisions based on relevant information from the CXR images. By no means a production-ready solution, the hope is that the open access COVID-Net, along with the description on constructing the open source COVIDx dataset, will be leveraged and build upon by both researchers and citizen data scientists alike to accelerate the development of highly accurate yet practical deep learning solutions for detecting COVID-19 cases and accelerate treatment of those who need it the most.
Tocilizumab (TCZ), a monoclonal antibody against interleukin‐6 (IL‐6), emerged as an alternative treatment for COVID‐19 patients with a risk of cytokine storms recently. In the present study, we ...aimed to discuss the treatment response of TCZ therapy in COVID‐19 infected patients. The demographic, treatment, laboratory parameters of C‐reactive protein (CRP) and IL‐6 before and after TCZ therapy and clinical outcome in the 15 COVID‐19 patients were retrospectively assessed. Totally 15 patients with COVID‐19 were included in this study. Two of them were moderately ill, six were seriously ill and seven were critically ill. The TCZ was used in combination with methylprednisolone in eight patients. Five patients received the TCZ administration twice or more. Although TCZ treatment ameliorated the increased CRP in all patients rapidly, for the four critically ill patients who received an only single dose of TCZ, three of them (No. 1, 2, and 3) still dead and the CRP level in the rest one patient (No. 7) failed to return to normal range with a clinical outcome of disease aggravation. Serum IL‐6 level tended to further spiked firstly and then decreased after TCZ therapy in 10 patients. A persistent and dramatic increase of IL‐6 was observed in these four patients who failed treatment. TCZ appears to be an effective treatment option in COVID‐19 patients with a risk of cytokine storms. And for these critically ill patients with elevated IL‐6, the repeated dose of the TCZ is recommended.
Research Highlights
TCZ benefits the COVID‐19 patients in relieving inflammatory activity.
Repeat doses of TCZ is recommended for critically ill COVID‐19 patients.
More cases are still needed to further verify the effect of TCZ.
Schizophrenia (SZ) and obsessive-compulsive disorder (OCD) share many demographic characteristics and severity of clinical symptoms, genetic risk factors, pathophysiological underpinnings, and brain ...structure and function. However, the differences in the spontaneous brain activity patterns between the two diseases remain unclear. Here this study aimed to compare the features of intrinsic brain activity in treatment-naive participants with SZ and OCD and to explore the relationship between spontaneous brain activity and the severity of symptoms.
In this study, 22 treatment-naive participants with SZ, 27 treatment-naive participants with OCD, and sixty healthy controls (HC) underwent a resting-state functional magnetic resonance imaging (fMRI) scan. The amplitude of low-frequency fluctuation (ALFF), regional homogeneity (ReHo) and degree of centrality (DC) were performed to examine the intrinsic brain activity of participants. Additionally, the relationships among spontaneous brain activity, the severity of symptoms, and the duration of illness were explored in SZ and OCD groups.
Compared with SZ group and HC group, participants with OCD had significantly higher ALFF in the right angular gyrus and the left middle frontal gyrus/precentral gyrus and significantly lower ALFF in the left superior temporal gyrus/insula/rolandic operculum and the left postcentral gyrus, while there was no significant difference in ALFF between SZ group and HC group. Compared with HC group, lower ALFF in the right supramarginal gyrus/inferior parietal lobule and lower DC in the right lingual gyrus/calcarine fissure and surrounding cortex of the two patient groups, higher ReHo in OCD group and lower ReHo in SZ group in the right angular gyrus/middle occipital gyrus brain region were documented in the present study. DC in SZ group was significantly higher than that in HC group in the right inferior parietal lobule/angular gyrus, while there were no significant DC differences between OCD group and HC group. In addition, ALFF in the left postcentral gyrus were positively correlated with positive subscale score (r = 0.588, P = 0.013) and general psychopathology subscale score (r = 0.488, P = 0.047) respectively on the Positive and Negative Syndrome Scale (PANSS) in SZ group. ALFF in the left superior temporal gyrus/insula/rolandic operculum of participants with OCD were positively correlated with compulsion subscale score (r = 0.463, P = 0.030) on the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). The longer the illness duration in SZ group, the smaller the ALFF of the left superior temporal gyrus/insula/rolandic operculum (Rho = 0.-492, P = 0.020). The longer the illness duration in OCD group, the higher the ALFF of the right supramarginal gyrus/inferior parietal lobule (Rho = 0.392, P = 0.043) and the left postcentral gyrus (Rho = 0.385, P = 0.048), and the lower the DC of the right inferior parietal lobule/angular gyrus (Rho = - 0.518, P = 0.006).
SZ and OCD show some similarities in spontaneous brain activity in parietal and occipital lobes, but exhibit different patterns of spontaneous brain activity in frontal, temporal, parietal, occipital, and insula brain regions, which might imply different underlying neurobiological mechanisms in the two diseases. Compared with OCD, SZ implicates more significant abnormalities in the functional connections among brain regions.
Nano/Microscale heat transfer is widely encountered in many fields of science and engineering, such as microelectronics, thermoelectrics, heat storage, thermal energy utilization, and thermal ...management ...
The fall armyworm (FAW), Spodoptera frugiperda is one of the most damaging crop pests, and it has become major threat to the food security of many countries. In order to monitor possible invasion of ...this pest into China, a searchlight trap was established in March 2018 in western Yunnan Province, China, where it has served as the “first station” for many pests that have migrated from Myanmar to China. A number of suspected FAW moths were captured and identified by DNA sequencing. The results showed that the FAW moth was first captured on December 11 and formed its first immigration peak in mid-December 2018. DNA detection revealed that the early invading FAW population was the “corn-strain”. The field survey indicated that the pest mainly colonized corn in Pu'er, Dehong and Baoshan areas. Migration trajectory simulation implied that the moths might have mainly come from the eastern area in the mid-latitude region of Myanmar (20–25°N, 94–100°E). This case study confirmed the first immigration of FAW into China, and will be helpful for guiding monitoring and management work to control this pest.
Although the individual one- and two-dimensional (1D and 2D) carbon nanostructures possess extremely high thermal conductivity, their macroscopic assemblies do not efficiently utilize it due to the ...larger interfacial contact thermal resistance. To improve the overall performance, the key is the interfacial structure design to provide sufficient pathways for phonon transport with a limited sacrifice or damage to the inherent thermal properties of nanomaterials. Particularly, the resonance of low-frequency lattice vibrations is the most important mechanism for the reduction of the interfacial contact thermal resistance. Based on recent theoretical and experimental studies and observations on interfacial heat transport, we review here a fourfold set of transport problems in this field: (1) low-frequency phonons in 1D and 2D nanostructures for heat transport; (2) the mechanisms of interfacial thermal transport; (3) assembly structure design towards high utilization of the thermal conductivity from individual nanostructures; and (4) recent development of thermal conductivity measurement for individual and assembled nanomaterials.
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•Low frequency phonons play important roles in thermal transport of nano-carbons.•Interfacial thermal transport is greatly determined by interfacial phonon coupling.•Recent progresses on the thermal conductivity of nano-carbon assemblies are reviewed.•Thermal conductivity measurement strategies and their related upgrades are discussed.
Bioactivity of soy-based fermented foods: A review Cao, Zhen-Hui; Green-Johnson, Julia M.; Buckley, Nicole D. ...
Biotechnology advances,
January-February 2019, 2019 Jan - Feb, 2019-01-00, 20190101, Letnik:
37, Številka:
1
Journal Article
Recenzirano
For centuries, fermented soy foods have been dietary staples in Asia and, now, in response to consumer demand, they are available throughout the world. Fermentation bestows unique flavors, boosts ...nutritional values and increases or adds new functional properties. In this review, we describe the functional properties and underlying action mechanisms of soy-based fermented foods such as Natto, fermented soy milk, Tempeh and soy sauce. When possible, the contribution of specific bioactive components is highlighted. While numerous studies with in vitro and animal models have hinted at the functionality of fermented soy foods, ascribing health benefits requires well-designed, often complex human studies with analysis of diet, lifestyle, family and medical history combined with long-term follow-ups for each subject. In addition, the contribution of the microbiome to the bioactivities of fermented soy foods, possibly mediated through direct action or bioactive metabolites, needs to be studied. Potential synergy or other interactions among the microorganisms carrying out the fermentation and the host's microbial community may also contribute to food functionality, but the details still require elucidation. Finally, safety evaluation of fermented soy foods has been limited, but is essential in order to provide guidelines for consumption and confirm lack of toxicity.
Total 22 organochlorine pesticides (OCPs) compounds and 31 polychlorinated biphenyls (PCBs) congeners in mangrove sediments and tissues (leaf, branch, root and fruit) of nine species from three ...Mangrove Reserves of China were studied. The mean concentrations of total DDTs, HCHs, OCPs and PCBs in sediments were 2.84, 0.06, 3.84 and 0.17 ng g−1 dw, while those in tissues were 1.85, 0.22, 9.43 and 1.61 ng g−1 dw, respectively. The elevated OCPs and PCBs levels in mangrove leaves may be caused by atmospheric sedimentation. The biota sediment accumulation factor (BSAF) values of both OCPs (mean: 3.4) and PCBs (mean: 9.9) are generally larger than one, implying mangroves' bioaccumulation and their ability to intercept pollutants. The BSAFs of PCBs in mangrove tissues were negatively correlated with the PCB congener's octanol-water partition coefficients (KOW, R = 0.58, n = 31, p < 0.001), suggesting that lower chlorinated CB congeners are more bioaccumulative in mangroves. In order to better understanding the fate of these organochlorine compounds, the cycling (including the standing accumulation, the annual absorption, the annual net retention, the annual return, and the turnover period) of OCPs and PCBs in the Mangrove Reserves were estimated, and the results indicated that mangroves are playing important roles in retaining OCPs and PCBs.
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•Concentrations of OCPs and PCBs in natural mangrove plants are reported.•The larger BSAF values of OCPs and PCBs (>1) suggest mangroves' bioaccumulation.•BSAF of PCB in mangrove branches is significantly correlated with log KOW.•Lower chlorinated PCB congeners are more bioaccumulative in mangroves.•Mangroves are playing important roles in retaining OCPs and PCBs.
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