49 research outputs found
Exome sequencing and functional analysis identifies a novel mutation in <em>EXT1</em>Â gene that causes multiple osteochondromas
Multiple osteochondromas (MO) is an inherited skeletal disorder, and the molecular mechanism of MO remains elusive. Exome sequencing has high chromosomal coverage and accuracy, and has recently been successfully used to identify pathogenic gene mutations. In this study, exome sequencing followed by Sanger sequencing validation was first used to screen gene mutations in two representative MO patients from a Chinese family. After filtering the data from the 1000 Genome Project and the dbSNP database (build 132), the detected candidate gene mutations were further validated via Sanger sequencing of four other members of the same MO family and 200 unrelated healthy subjects. Immunohistochemisty and multiple sequence alignment were performed to evaluate the importance of the identified causal mutation. A novel frameshift mutation, c.1457insG at codon 486 of exon 6 of EXT1 gene, was identified, which truncated the glycosyltransferase domain of EXT1 gene. Multiple sequence alignment showed that codon 486 of EXT1 gene was highly conserved across various vertebrates. Immunohistochemisty demonstrated that the chondrocytes with functional EXT1 in MO were less than those in extragenetic solitary chondromas. The novel c.1457insG deleterious mutation of EXT1 gene reported in this study expands the causal mutation spectrum of MO, and may be helpful for prenatal genetic screening and early diagnosis of MO
The chemical profiling of Salvia plebeia during different growth periods and the biosynthesis of its main flavonoids ingredients
Salvia plebeia (Lamiaceae) is a valuable medicinal plant widely distributed across Asia and Oceania. However, the composition and accumulation patterns of its active ingredients in different organs during the growth and their biosynthetic mechanism remain unknown. Therefore, we conducted metabolite profiling, transcriptomic analysis, and biological functional verification to explore the distribution, accumulation, and biosynthesis mechanisms of flavonoids in S. plebeia. We identified 70 metabolites including 46 flavonoids, 16 phenolic acids, seven terpenoids, and one organic acid, of which 21 were previously unreported in S. plebeia. Combining metabolomic-transcriptomic analysis and biological functional verification, we identified the key genes involved in biosynthesis of its main active ingredients, hispidulin and homoplantaginin, including SpPAL, SpC4H, Sp4CL2, Sp4CL5, SpCHS1, SpCHI, SpFNS, SpF6H1, SpF6OMT1, SpF6OMT2, SpUGT1, SpUGT2, and SpUGT3. Using the identified genes, we reconstructed the hispidulin and homoplantaginin biosynthesis pathways in Escherichia coli, and obtained a yield of 5.33 and 3.86 mg/L for hispidulin and homoplantaginin, respectively. Our findings provide valuable insights into the changes in chemical components in different organs of S. plebeia during different growth and harvest stages and establishes a foundation for identifying and synthesizing its active components
Molecular genetic analysis using targeted NGS analysis of 677 individuals with retinal dystrophy
Abstract Inherited retinal diseases (IRDs) are a common cause of visual impairment. IRD covers a set of genetically highly heterogeneous disorders with more than 150 genes associated with one or more clinical forms of IRD. Molecular genetic diagnosis has become increasingly important especially due to expanding number of gene therapy strategies under development. Next generation sequencing (NGS) of gene panels has proven a valuable diagnostic tool in IRD. We present the molecular findings of 677 individuals, residing in Denmark, with IRD and report 806 variants of which 187 are novel. We found that deletions and duplications spanning one or more exons can explain 3% of the cases, and thus copy number variation (CNV) analysis is important in molecular genetic diagnostics of IRD. Seven percent of the individuals have variants classified as pathogenic or likely-pathogenic in more than one gene. Possible Danish founder variants in EYS and RP1 are reported. A significant number of variants were classified as variants with unknown significance; reporting of these will hopefully contribute to the elucidation of the actual clinical consequence making the classification less troublesome in the future. In conclusion, this study underlines the relevance of performing targeted sequencing of IRD including CNV analysis as well as the importance of interaction with clinical diagnoses
Case report: Reversible splenial lesion syndrome caused by diquat poisoning
Diquat (DQ), chemically known as 1,1 â-ethylene-2,2â -bipyridine, is a non-selective herbicide for leaf removal and drying. It has toxic effects on central nervous system cells, and toxic neurological lesions include axonal degeneration and pontine myelolysis. At the same time, DQ can also affect the activity of dopaminergic nerve cells through oxidative stress, causing degeneration and reducing dopamine uptake. With the increasing application of DQ in agricultural production, the clinical reports of neurotoxicity caused by acute DQ poisoning are also increasing. At present, DQ rapid-phase-related toxic encephalopathy mainly involves the pons, midbrain, basal ganglia, thalamus and other brain regions. However, this case is unusual in that the lesion mainly involved the splenium of the corpus callosum. It is also the first time to be reported
The Effect of Superabsorbent Polymer on the Resilient and Plastic Strain Behavior of Cemented Soil under Traffic Load
In road construction, a large number of excavated soils need to be treated with stabilizers. The addition of superabsorbent polymer (SAP) can improve the road performance of these stabilized soils. In order to predict roadbed deformation, dynamic triaxial tests were carried out on cemented soil containing SAP to investigate its resilient and plastic strain behavior. The effects of SAP content, cyclic stress ratio, and loading frequency on cement-stabilized soils with SAP were analyzed combined with the number of cycles. This study demonstrates how these influencing factors effect the resilient strain, dynamic elastic modulus, and accumulated plastic strain, which are crucial to better understanding the strain behavior of cement-stabilized soil with SAP. The results show that SAP can significantly improve the brittle failure characteristics and dynamic strength of cement-stabilized soil. Soil with higher SAP content possesses smaller accumulated plastic strain; with the increase in the cyclic stress ratio, the dynamic elastic modulus decreases significantly, whereas the accumulated plastic strain has the opposite trend. In addition, the lower frequency produces larger cumulative axial strain
Chemical composition, antimicrobial and antioxidant activities of essential oil from flue-cured tobacco flower bud
Essential oils generally derived from one or more plant parts have been used throughout history for many great applications. In this study, the flue-cured tobacco flower buds were subjected to hydrodistillation in a Clevenger-type apparatus (4 h). The essential oil was characterized by means of gas chromatographyâmass spectrometry (GCâMS). The yield of the oil was 0.57% (w/w). After identification of the components, 34 volatile compounds were identified, which contained 55.0% of the oil. β-Cembrenediol (12.24%), carotol (8.55%), isolimonene (7.37%), thunbergol (4.88%) and 9,12-octadecadienoic acid (4.09%) were the major constituents of the oil. The essential oil was also tested for antimicrobial and antioxidant activities. The essential oil was particularly active against Bacillus subtilis, with the lowest Minimal Inhibitory Concentration and Minimum Bactericidal Concentration value (7 and 7 mg/mL). Furthermore, the essential oil and its main compounds showed a strong potent OH scavenging effect, when compared to butylated hydroxytoluene as a positive control. In conclusion, the tobacco flower bud oil is a potential source of novel antioxidant and antimicrobial agents
A Mouse Model of Enterovirus D68 Infection for Assessment of the Efficacy of Inactivated Vaccine
In recent years, enterovirus D68 (EVD68) has been reported increasingly to be associated with severe respiratory tract infections and acute flaccid myelitis (AFM) in children all over the world. Yet, no effective vaccines or antiviral drugs are currently available for EVD68. Although several experimental animal models have been developed, immunogenicity and protective efficacy of inactivated EVD68 vaccines has not been fully evaluated. To promote the development of vaccines, we established an Institute of Cancer Research (ICR) suckling mouse model of EVD68 infection in this study. The results showed that ICR neonatal mice up to about nine days of age were susceptible to infection with EVD68 clinical strain US/MO/14-18947 by intraperitoneal injection. The infected mice exhibited progressive limb paralysis prior to death and the mortality of mice was age- and virus dose-dependent. Tissue viral load analysis showed that limb muscle and spinal cord were the major sites of viral replication. Moreover, histopathologic examination revealed the severe necrosis of the limb and juxtaspinal muscles, suggesting that US/MO/14-18947 has a strong tropism toward muscle tissues. Additionally, β-propiolactone-inactivated EVD68 vaccine showed high purity and quality and induced robust EVD68-specific neutralizing antibody responses in adult mice. Importantly, results from both antisera transfer and maternal immunization experiments clearly showed that inactivated EVD68 vaccine was able to protect against lethal viral infection in the mouse model. In short, these results demonstrate the successful establishment of the mouse model of EVD68 infection for evaluating candidate vaccines against EVD68 and also provide important information for the development of inactivated virus-based EVD68 vaccines
On the chronological understanding of the homogeneous dielectric barrier discharge
Abstract Dielectric barrier discharges (DBD) are widely utilised nonâequilibrium atmospheric pressure plasmas with a diverse range of applications, such as material processing, surface treatment, light sources, pollution control, and medicine. Over the course of several decades, extensive research has been dedicated to the generation of homogeneous DBD (HâDBD), focussing on understanding the transition from HâDBD to filamentary DBD and exploring strategies to create and sustain HâDBD. This paper first discusses the influence of various parameters on DBD, including gas flow, dielectric material, surface conductivity, and mesh electrode. Secondly, a chronological literature review is presented, highlighting the development of HâDBD and the associated understanding of its underlying mechanisms. This encompasses the generation of HâDBD in helium, nitrogen, and air. Lastly, the paper provides a brief overview of multipleâcurrentâpulse (MCP) behaviours in HâDBD. The objective of this article is to provide a chronological understanding of homogeneous dielectric barrier discharge (DBD). This understanding will aid in the design of new experiments aimed at better comprehending the mechanisms behind HâDBD generation and ultimately assist in achieving largeâvolume HâDBD in an air environment