Rapid, sensitive, and one-pot diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) plays an extremely important role in point-of-care testing (POCT). Herein, we report an ...ultra-sensitive and rapid one-pot enzyme-catalyzed rolling circle amplification-assisted CRISPR/FnCas12a assay, termed OPERATOR. OPERATOR employs a single well-designed single-strand padlock DNA, containing a protospacer adjacent motif (PAM) site and a sequence complementary to the target RNA which procedure converts and amplifies genomic RNA to DNA by RNA-templated DNA ligation and multiply-primed rolling circle amplification (MRCA). The MRCA amplicon of single-stranded DNA is cleaved by the FnCas12a/crRNA complex and detected via a fluorescence reader or lateral flow strip. OPERATOR presents outstanding advantages including ultra-sensitivity (1.625 copies per reaction), high specificity (100%), rapid reaction speed (∼30 min), easy operation, low cost, and on-spot visualization. Furthermore, we established a POCT platform by combining OPERATOR with rapid RNA release and a lateral flow strip without professional equipment. The high performance of OPERATOR in SARS-CoV-2 tests was confirmed using both reference materials and clinical samples, and the results suggest that is readily adaptable for point-of-care testing of other RNA viruses.
The research of heavy metals in high-selenium soil is critical for the land utilization. Langao County in Southern Shaanxi, a typical high-selenium area in China, was studied to examine the ...distribution, source identification, safely utilization of heavy metals in surface soils. Content of heavy metals (As, Cr, Cu, Ni, Pb, Zn, Cd and Hg) were measured in 360 surface soil samples, 12 layered soil samples from Langao County, and 8 surface soil samples from different geological units in other regions. The results show: (1) Except for Hg, the mean concentrations of As, Cr, Cu, Ni, Pb, Zn and Cd were greater than Chinese and Shaanxi province background values. (2) The spatial distribution of heavy metal concentration in surface soil is greater in the northern region and lower in the southern region, which is compatible with the stratigraphic trend (northwest-southeast trend). Langao County has three possible heavy metal sources: (1) Weathering and leaching of rocks or parent materials (As, Cu, Zn, Cd and Hg); (2) Agricultural activities (Cr and Ni). (3) Transportation (Pb). (3) As, Cr, Ni and Cd in surface soils have potential carcinogenic risks. (4) For safe utilization of land, 5.68% of the land area should be strictly protected, 75.90% of the land area should be applied with substitute planting, 18.42% of the land area should be strictly prohibited from planting agricultural products. This research might provide a theoretical foundation for scientific land management in high-selenium area.
Determining the structures of previously unseen compounds from experimental characterizations is a crucial part of materials science. It requires a step of searching for the structure type that ...conforms to the lattice of the unknown compound, which enables the pattern matching process for characterization data, such as X-ray diffraction (XRD) patterns. However, this procedure typically places a high demand on domain expertise, thus creating an obstacle for computer-driven automation. Here, we address this challenge by leveraging a deep-learning model composed of a union of convolutional residual neural networks. The accuracy of the model is demonstrated on a dataset of over 60,000 different compounds for 100 structure types, and additional categories can be integrated without the need to retrain the existing networks. We also unravel the operation of the deep-learning black box and highlight the way in which the resemblance between the unknown compound and a structure type is quantified based on both local and global characteristics in XRD patterns. This computational tool opens new avenues for automating structure analysis on materials unearthed in high-throughput experimentation.
The catalytic epoxidation of α-olefin with long carbon chains has always been a challenge. Traditional homogeneous or heterogeneous catalysts showed poor performance toward the reaction. In this ...paper, layered organic–inorganic catalysts were prepared by the reaction of phosphotungstic acid and a Gemini quaternary ammonium salt, which could convert long α-olefin to epoxide with a selectivity of 85% in the absence of organic solvents. Combined with characterization results, it was confirmed that the catalyst was layered structure materials, which was supported by a quaternary ammonium salt chain, and the active molecules were distributed between the layered structures. The possible mechanism was also discussed preliminarily.
ObjectivesThe aim of this study was to evaluate the performance of deep learning-based detection and classification of carotid plaque (DL-DCCP) in carotid plaque contrast-enhanced ultrasound ...(CEUS).Methods and analysisA prospective multicentre study was conducted to assess vulnerability in patients with carotid plaque. Data from 547 potentially eligible patients were prospectively enrolled from 10 hospitals, and 205 patients with CEUS video were finally enrolled for analysis. The area under the receiver operating characteristic curve (AUC) was used to evaluate the effectiveness of DL-DCCP and two experienced radiologists who manually examined the CEUS video (RA-CEUS) in diagnosing and classifying carotid plaque vulnerability. To evaluate the influence of dynamic video input on the performance of the algorithm, a state-of-the-art deep convolutional neural network (CNN) model for static images (Xception) was compared with DL-DCCP for both training and holdout validation cohorts.ResultsThe AUCs of DL-DCCP were significantly better than those of the experienced radiologists for both the training and holdout validation cohorts (training, DL-DCCP vs RA-CEUS, AUC: 0.85 vs 0.69, p<0.01; holdout validation, DL-DCCP vs RA-CEUS, AUC: 0.87 vs 0.66, p<0.01), that is, also better than the best deep CNN model Xception we had performed, for both the training and holdout validation cohorts (training, DL-DCCP vs Xception, AUC:0.85 vs 0.82, p<0.01; holdout validation, DL-DCCP vs Xception, AUC: 0.87 vs 0.77, p<0.01).ConclusionDL-DCCP shows better overall performance in assessing the vulnerability of carotid atherosclerotic plaques than RA-CEUS. Moreover, with a more powerful network structure and better utilisation of video information, DL-DCCP provided greater diagnostic accuracy than a state-of-the-art static CNN model.Trial registration numberChiCTR1900021846,
A high aluminum (Al) content
-(Al
Ga
)
O
film was synthesized on c-plane sapphire substrate using the gallium (Ga) diffusion method. The obtained
-(Al
Ga
)
O
film had an average thickness of 750 nm ...and a surface roughness of 2.10 nm. Secondary ion mass spectrometry results indicated the homogenous distribution of Al components in the film. The Al compositions in the
-(Al
Ga
)
O
film, as estimated by X-ray diffraction, were close to those estimated by X-ray photoelectron spectroscopy, at ~62% and ~61.5%, respectively. The bandgap of the
-(Al
Ga
)
O
film, extracted from the O 1s core-level spectra, was approximately 6.0 ± 0.1 eV. After synthesizing the
-(Al
Ga
)
O
film, a thick
-Ga
O
film was further deposited on sapphire substrate using carbothermal reduction and halide vapor phase epitaxy. The
-Ga
O
thick film, grown on a sapphire substrate with a
-(Al
Ga
)
O
buffer layer, exhibited improved crystal orientation along the (-201) plane. Moreover, the scanning electron microscopy revealed that the surface quality of the
-Ga
O
thick film on sapphire substrate with a
-(Al
Ga
)
O
intermediate buffer layer was significantly improved, with an obvious transition from grain island-like morphology to 2D continuous growth, and a reduction in surface roughness to less than 10 nm.
Background:
Meckel Syndrome (MKS, OMIM #249000) is a rare and fatal autosomal recessive ciliopathy with high clinical and genetic heterogeneity. MKS shows complex allelism with other related ...ciliopathies such as Joubert Syndrome (JBTS, OMIM #213300). In MKS, the formation and function of the primary cilium is defective, resulting in a multisystem disorder including occipital encephalocele, polycystic kidneys, postaxial polydactyly, liver fibrosis, central nervous system malformations and genital anomalies. This study aimed to analyze the genotype of MKS patients and investigate the correlation between genotype and phenotype.
Methods:
A nonconsanguineous couple who conceived four times with a fetus affected by multiorgan dysfunction and intrauterine fetal death was studied. Whole exome sequencing (WES) was performed in the proband to identify the potentially pathogenic variant. Sanger sequencing was performed in family members. In silico tools were used to analyse the pathogenicity of the identified variants. cDNA TA-cloning sequencing was performed to validate the effects of intronic variants on mRNA splicing. Quantitative real-time PCR was performed to investigate the effect of the variants on gene expression. Immunofluorescence was performed to observe pathological changes of the primary cilium in kidney tissue from the proband.
Results:
Two splice site variants of
TMEM231
(NM_001077418.2, c.583-1G>C and c.583-2_588delinsTCCTCCC) were identified in the proband, and the two variants have not been previously reported. The parents were confirmed as carriers. The two variants were predicted to be pathogenic by
in silico
tools and were classified as pathogenic/likely pathogenic variants according to the American College of Medical Genetics and Genomics guideline. cDNA TA cloning analysis showed that both splice site variants caused a deletion of exon 5. RT-PCR revealed that the expression of
TMEM231
was significantly decreased and immunofluorescence showed that the primary cilium was almost absent in the proband’s kidney tissue.
Conclusion:
We reported the clinical, genetic, molecular and histochemical characterisation of a family affected by MKS. Our findings not only extended the mutation spectrum of the
TMEM231
gene, but also revealed for the first time the pathological aetiology of primary cilia in humans and provide a basis for genetic counselling of the parents to their offspring.
The patterns of communication among different chondrocyte subtypes in human cartilage degeneration and regeneration help us understand the microenvironment of osteoarthritis and optimize ...cell-targeted therapies. Here, a single-cell transcriptome dataset of chondrocytes is used to explore the synergistic and communicative patterns of different chondrocyte subtypes. We collected 1600 chondrocytes from 10 patients with osteoarthritis and analyzed the active communication patterns for the first time based on network analysis and pattern recognition at the single-cell level. Manifold learning and quantitative contrasts were performed to analyze conserved and specific communication pathways. We found that ProCs (Proliferative chondrocytes), ECs (Effector chondrocytes), preHTCs (Prehypertrophic chondrocytes), HTCs (Hypertrophic chondrocytes), and FCs (Fibrocartilage chondrocytes) are more active in incoming and outgoing signaling patterns, which is consistent with studies on their close functional cooperation. Among them, preHTCs play multiple roles in chondrocyte communication, and ProCs and preHTCs have many overlapping pathways. These two subtypes are the most active among all chondrocyte subtypes. Interestingly, ECs and FCs are a pair of "mutually exclusive" subtypes, of which ECs are predominant in incoming patterns and FCs in outgoing patterns. The active signaling pathways of ECs and FCs largely do not overlap. COLLAGEN and LAMININ are the main pivotal pathways, which means they are very important in the repair and expansion of joint homeostasis. Notably, only preHTCs assume multiple roles (including sender, receiver, mediator, and influencer) and are involved in multiple communication pathways. We have examined their communication patterns from the perspective of cellular interactions, revealed the relationships among different chondrocyte subtypes, and, in particular, identified a number of active subtypes and pathways that are important for targeted therapy in the osteoarthritic microenvironment. Our findings provide a new research paradigm and new insights into understanding chondrocyte activity patterns in the osteoarthritic microenvironment.
Cities are prone to ecological problems, yet the impacts of rapid global urbanization on the feedback between above- and belowground subsystems remain largely unknown. We sampled the roots of 8 ...common herbaceous plants within the Fifth Ring (urban areas) and in Jiufeng National Forest Park (rural areas) in Beijing (China) to assess the impacts of urbanization on the network of plant-arbuscular mycorrhizal (AM) fungal associations. Using Illumina MiSeq sequencing, 81 AM fungal OTUs were identified in 78 herb root samples. The Shannon, Simpson, and Pielou indices of root AM fungi in urban areas were significantly higher than those in rural areas. In this study, a significantly nested mycorrhizal association network was observed in rural areas (NODF = 64.68), whereas a non-nested pattern was observed in urban areas (NODF = 55.50). The competition index C-score (0.0769) of AM fungi in urban areas was slightly lower than that in rural areas (0.1431), and the species specialization (
') of 8 host plants and fungal dissimilarity among 8 host plants in urban areas were significantly lower than those in rural areas. Convergent associations among hosts may be an important factor influencing this non-nested pattern of the plant-AM fungi network in urban areas. Generalists, rather than specialists, were enhanced during the establishment of mycorrhizal associations in urban areas. Our results suggest that reduced selectivity of host plants, and generalist promotion and specialist reduction of AM fungi during urbanization may contribute to the non-nested network of plant-AM fungal associations.
Summary
Maternal obesity leads to obstetric complications and a high prevalence of metabolic anomalies in the offspring. Among various contributing factors for maternal obesity‐evoked health ...sequelae, developmental programming is considered as one of the leading culprit factors for maternal obesity‐associated chronic comorbidities. Although a unified theory is still lacking to systematically address multiple unfavorable postnatal health sequelae, a cadre of etiological machineries have been put forward, including lipotoxicity, inflammation, oxidative stress, autophagy/mitophagy defect, and cell death. Hereinto, autophagy and mitophagy play an essential housekeeping role in the clearance of long‐lived, damaged, and unnecessary cell components to maintain and restore cellular homeostasis. Defective autophagy/mitophagy has been reported in maternal obesity and negatively impacts fetal development and postnatal health. This review will provide an update on metabolic disorders in fetal development and postnatal health issues evoked by maternal obesity and/or intrauterine overnutrition and discuss the possible contribution of autophagy/mitophagy in metabolic diseases. Moreover, relevant mechanisms and potential therapeutic strategies will be discussed in an effort to target autophagy/mitophagy and metabolic disturbances in maternal obesity.
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