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1.
Braz J Med Biol Res ; 54(12): e11232, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669781

RESUMO

Follicular regulatory T cells (Tfr) have critical functions in inflammatory and autoimmune disorders. The main purpose of the current work was to assess Tfr cell frequency in patients with dilated cardiomyopathy (DCM). Flow cytometry showed that, compared with normal controls, DCM cases showed markedly reduced Tfr cell rates and Tfr/Tfh ratios, but significantly increased follicular helper T cell (Tfh) rates. Correlation analysis showed that the Tfr rate in DCM patients was positively correlated with left ventricular ejection fraction (LVEF), and negatively correlated with N-terminal brain natriuretic peptide (NT-proBNP) levels. Lower Foxp3 and higher Bcl-6, ICOS, and PD-1 mRNA expression levels were found in patients with DCM. In addition, plasma interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-21 levels were significantly increased in DCM cases. Moreover, IgG and IgG3 levels were also elevated in individuals with DCM. Correlation analysis showed that the Tfr rate in DCM patients was negatively correlated with IgG and IgG3, while the Tfh rate was positively correlated with IgG and IgG3. Changes in circulating Tfr levels may have a critical immunomodulatory function in DCM and may become a new therapeutic target for DCM.

2.
Diabetes Res Clin Pract ; 180: 109040, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34500005

RESUMO

OBJECTIVES: To develop and validate a model for predicting the risk of early diabetic foot ulcer (DFU) based on systematic review and meta-analysis. METHODS: Data were analyzed from the risk factors of DFU with their corresponding risk ratio (RR) by meta-analysis. The DFU prediction model included statistically significant risk factors from the meta-analysis, all of which were scored by its weightings, and the prediction model was externally validated using a validation cohort from China. The occurrence of early DFU was defined as patients with type 2 diabetes who were free of DFU at baseline and diagnosed with DFU at follow-up. Evaluation of model performance was based on the area under the discrimination receiver operating characteristic curve (ROC), with optimal cutoff point determined by calculation of sensitivity and specificity. Kaplan-Meier curve were performed tocompare the cumulative risk of different groups. RESULTS: Our meta-analysis confirmed a cumulative incidence of approximately 6.0% in 46,521 patients with diabetes. The final risk prediction model included Sex, BMI, HbA1c, Smoker, DN, DR, DPN, Intermittent Claudication, Foot care, and their RRs were 1.87, 1.08, 1.21, 1.77, 2.97, 2.98, 2.76, 3.77, 0.38, respectively. The total score of all risk factors was 80 points according to their weightings. The prediction model showed good discrimination with AUC = 0.798 (95 %CI 0.738-0.858). At the optimal cut-off value of 46.5 points, the sensitivity, specificity and Youden index were 0.769, 0.798 and 0.567, respectively. The final model stratified the validation cohort into low, low-intermediate, high-intermediate and high-risk groups; Compared with low-risk group, the RR with 95 %CI of developing DFU in high-intermediate and high-risk group were 17.23 (5.12-58.02), p < 0.01 and 46.11 (5.16-91.74), p < 0.01, respectively. CONCLUSION: We have developed a simple tool to facilitates early identification of patients with diabetes at high risk of developing DFU based on scores. This simple tool may improve clinical decision-making and potentially guide early intervention.

3.
CNS Neurosci Ther ; 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34551193

RESUMO

AIM: The role of vascular dementia (VaD)-associated genes in Alzheimer's disease (AD) remains elusive despite similar clinical and pathological features. We aimed to explore the relationship between these genes and AD in the Chinese population. METHODS: Eight VaD-associated genes were screened by a targeted sequencing panel in a sample of 3604 individuals comprising 1192 AD patients and 2412 cognitively normal controls. Variants were categorized into common variants and rare variants according to minor allele frequency (MAF). Common variant (MAF ≥ 0.01)-based association analysis was conducted by PLINK 1.9. Rare variant (MAF < 0.01) association study and gene-based aggregation testing of rare variants were performed by PLINK 1.9 and Sequence Kernel Association Test-Optimal (SKAT-O test), respectively. Age at onset (AAO) and Mini-Mental State Examination (MMSE) association studies were performed with PLINK 1.9. Analyses were adjusted for age, gender, and APOE ε4 status. RESULTS: Four common COL4A1 variants, including rs874203, rs874204, rs16975492, and rs1373744, exhibited suggestive associations with AD. Five rare variants, NOTCH3 rs201436750, COL4A1 rs747972545, COL4A1 rs201481886, CST3 rs765692764, and CST3 rs140837441, showed nominal association with AD risk. Gene-based aggregation testing revealed that HTRA1 was nominally associated with AD. In the AAO and MMSE association studies, variants in GSN, ITM2B, and COL4A1 reached suggestive significance. CONCLUSION: Common variants in COL4A1 and rare variants in HTRA1, NOTCH3, COL4A1, and CST3 may be implicated in AD pathogenesis. Besides, GSN, ITM2B, and COL4A1 are probably involved in the development of AD endophenotypes.

4.
Artigo em Inglês | MEDLINE | ID: mdl-34299692

RESUMO

The surface urban heat island (SUHI) effect poses a significant threat to the urban environment and public health. This paper utilized the Local Climate Zone (LCZ) classification and land surface temperature (LST) data to analyze the seasonal dynamics of SUHI in Wuhan based on the Google Earth Engine platform. In addition, the SUHI intensity derived from the traditional urban-rural dichotomy was also calculated for comparison. Seasonal SUHI analysis showed that (1) both LCZ classification and the urban-rural dichotomy confirmed that Wuhan's SHUI effect was the strongest in summer, followed by spring, autumn and winter; (2) the maximum SUHI intensity derived from LCZ classification reached 6.53 °C, which indicated that the SUHI effect was very significant in Wuhan; (3) LCZ 8 (i.e., large low-rise) had the maximum LST value and LCZ G (i.e., water) had the minimum LST value in all seasons; (4) the LST values of compact high-rise/midrise/low-rise (i.e., LCZ 1-3) were higher than those of open high-rise/midrise/low-rise (i.e., LCZ 4-6) in all seasons, which indicated that building density had a positive correlation with LST; (5) the LST values of dense trees (i.e., LCZ A) were less than those of scattered trees (i.e., LCZ B) in all seasons, which indicated that vegetation density had a negative correlation with LST. This paper provides some useful information for urban planning and contributes to the healthy and sustainable development of Wuhan.


Assuntos
Monitoramento Ambiental , Temperatura Alta , China , Cidades , Estações do Ano
5.
Front Aging Neurosci ; 13: 695808, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220489

RESUMO

The strategies of classifying APP, PSEN1, and PSEN2 variants varied substantially in the previous studies. We aimed to re-evaluate these variants systematically according to the American college of medical genetics and genomics and the association for molecular pathology (ACMG-AMP) guidelines. In our study, APP, PSEN1, and PSEN2 variants were collected by searching Alzforum and PubMed database with keywords "PSEN1," "PSEN2," and "APP." These variants were re-evaluated based on the ACMG-AMP guidelines. We compared the number of pathogenic/likely pathogenic variants of APP, PSEN1, and PSEN2. In total, 66 APP variants, 323 PSEN1 variants, and 63 PSEN2 variants were re-evaluated in our study. 94.91% of previously reported pathogenic variants were re-classified as pathogenic/likely pathogenic variants, while 5.09% of them were variants of uncertain significance (VUS). PSEN1 carried the most prevalent pathogenic/likely pathogenic variants, followed by APP and PSEN2. Significant statistically difference was identified among these three genes when comparing the number of pathogenic/likely pathogenic variants (P < 2.2 × 10-16). Most of the previously reported pathogenic variants were re-classified as pathogenic/likely pathogenic variants while the others were re-evaluated as VUS, highlighting the importance of interpreting APP, PSEN1, and PSEN2 variants with caution according to ACMG-AMP guidelines.

6.
Science ; 373(6554): 556-561, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34326238

RESUMO

Thermoelectric materials transfer heat and electrical energy, hence they are useful for power generation or cooling applications. Many of these materials have narrow bandgaps, especially for cooling applications. We developed SnSe crystals with a wide bandgap (E g ≈ 33 k B T) with attractive thermoelectric properties through Pb alloying. The momentum and energy multiband alignments promoted by Pb alloying resulted in an ultrahigh power factor of ~75 µW cm-1 K-2 at 300 K, and an average figure of merit ZT of ~1.90. We found that a 31-pair thermoelectric device can produce a power generation efficiency of ~4.4% and a cooling ΔT max of ~45.7 K. These results demonstrate that wide-bandgap compounds can be used for thermoelectric cooling applications.

7.
Neurobiol Aging ; 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34172279

RESUMO

Alzheimer's disease (AD) and frontotemporal dementia (FTD) overlap clinically and pathologically. However, the role of FTD-associated genes in patients with AD remained unclear. To explore the relationship between FTD-associated genes and AD risk, we investigated 14 FTD-associated genes via targeted next-generation sequencing panel or whole-genome sequencing in a total of 721 AD patients and 1391 controls. Common variant-based association analysis and gene-based association test of rare variants were performed by PLINK 1.9 and Sequence Kernel Association Test-Optimal (SKAT-O test) respectively. As a result, 2 common variants, UBQLN1 rs1044175 (p value = 2.76 × 10-4) and MAPT rs2258689 (p value = 5.71 × 10-4), differed significantly between AD patients and controls. Additionally, gene-based analysis aggregating rare variants demonstrated that HNRNPA1 reached statistical significance in the SKAT-O test (p value = 2.24 × 10-3). Protein-protein interaction analysis showed that UBQLN1, MAPT, and HNRNPA1 interacted with proteins encoded by well-recognized AD-associated genes. Our study indicated that UBQLN1, MAPT, and HNRNPA1 are implicated in the pathogenesis of AD in the mainland Chinese population.

8.
Environ Pollut ; 284: 117445, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062429

RESUMO

Quantitative estimation of soil organic carbon (SOC) is essential for the study of the C cycle and global C storage. Soil spectroscopic technology provides a cost-effective and time-efficient method for SOC quantification and has been successfully used to determine SOC storage. However, the SOC estimation accuracy remains limited by other soil properties, particularly soil water. In this study, we proposed a new deep learning algorithm named the Water Absorption Trough Dewatering Machine (WATDM) to improve estimations of SOC from soil reflectance spectra and reduce the effect of soil water. Soil water and reflectance spectral data of soil samples were measured using spectrometry. Based on the soil water contents derived from the water absorption troughs around 1900 nm, the optimal WATDM model was obtained and treated as the final model of the WATDM method, which performed better than a multiple linear regression model based on moist soil samples. The findings of this study indicate that the WATDM method can improve the estimation accuracy of SOC content by reducing the effect of soil water and can be used as a valuable new methodology within the spectroscopic estimation of soil properties.


Assuntos
Carbono , Solo , Ciclo do Carbono , Modelos Lineares , Água
9.
CNS Neurosci Ther ; 27(8): 930-940, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33942994

RESUMO

AIMS: NOTCH3 gene mutations predominantly cause cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, a common etiology of subcortical vascular dementia (SVaD). Besides, there may be a pathogenic link between NOTCH3 variants and Alzheimer's disease (AD). We aimed to study the role of NOTCH3 variants in AD and SVaD patients. METHODS: We recruited 763 patients with dementia (667 AD and 96 SVaD) and 365 healthy controls from the Southern Han Chinese population. Targeted capture sequencing was performed on NOTCH3 coding and adjacent intron regions to detect the pathogenic variants in AD and SVaD. The relationship between common or rare NOTCH3 variants and AD was further analyzed using Plink1.9. RESULTS: Five known pathogenic variants (p.R182C, p.C201S, p.R544C, p.R607C, and p.R1006C) and two novel likely pathogenic variants (p.C201F and p.C1061F) were detected in 16 SVaD patients. Additionally, no pathogenic or likely pathogenic variants were found in AD patients. NOTCH3 was not associated with AD in either single-variant association analysis or gene-based association analysis. CONCLUSION: Our findings broaden the mutational spectrum of NOTCH3 and validate the pathogenic role of NOTCH3 mutations in SVaD, but do not support the notion that NOTCH3 variation influences the risk of AD.

10.
Diabetes Metab Syndr Obes ; 14: 2209-2216, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34040406

RESUMO

Objective: This study aimed to summarize the distribution pattern of traditional Chinese medicine (TCM) syndromes in patients with type 2 diabetes mellitus (T2DM). Methods: The frequency, characteristics and distribution of all TCM syndromes of 549 patients with T2DM were analyzed. Results: The average age of T2DM onset was higher in women than in men (ie, men experienced earlier onset). The distribution of TCM syndromes, in order of frequency, was as follows: damp-heat trapping spleen (including spleen deficiency and dampness, damp heat due to spleen deficiency, and qi weakness due to spleen deficiency) (58.29%), qi-yin deficiency (16.03%), deficiency of yin and excessive heat (12.93%), blood stasis in collaterals (9.41%), and yin-yang deficiency (3.21%). The physical intensity of patients' occupational activity was mainly light (49.6%), followed by heavy (31.4%) and moderate (19.0%). Conclusion: Damp-heat trapping spleen is the most common TCM syndrome in patients with T2DM, with damp heat due to spleen deficiency the most significant subtype. This syndrome tends to occur in people over the age of 60 and those undertaking too much or too little physical activity in their occupational activities. The traditional "three more and one less" symptoms do not adequately describe the clinical symptoms of T2DM.

11.
Nat Commun ; 12(1): 3234, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34050188

RESUMO

We demonstrate that the thermoelectric properties of p-type chalcogenides can be effectively improved by band convergence and hierarchical structure based on a high-entropy-stabilized matrix. The band convergence is due to the decreased light and heavy band energy offsets by alloying Cd for an enhanced Seebeck coefficient and electric transport property. Moreover, the hierarchical structure manipulated by entropy engineering introduces all-scale scattering sources for heat-carrying phonons resulting in a very low lattice thermal conductivity. Consequently, a peak zT of 2.0 at 900 K for p-type chalcogenides and a high experimental conversion efficiency of 12% at ΔT = 506 K for the fabricated segmented modules are achieved. This work provides an entropy strategy to form all-scale hierarchical structures employing high-entropy-stabilized matrix. This work will promote real applications of low-cost thermoelectric materials.

12.
Environ Sci Pollut Res Int ; 28(35): 48298-48311, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33904137

RESUMO

COVID-19 has caused huge impacts on human health and the economic operation of the world. Analyzing and summarizing the early propagation law can help reduce the losses caused by public health emergencies in the future. Early data on the spread of COVID-19 in 30 provinces (autonomous regions and municipalities) of mainland China except for Hubei, Hong Kong, Macao, and Taiwan were selected in this study. Spatio-temporal analysis, inflection point analysis, and correlation analysis are used to explore the spatio-temporal characteristics in the early COVID-19 spread. The results suggested that (1) the total confirmed cases have risen in an "S"-shaped curve over time, and the daily new cases have first increased and finally decreased; (2) the spatial distributions of both total and daily new cases show a trend of more in the east and less in the west, with a "multi-center agglomeration distribution" around Hubei Province and some major cities; (3) the spatial agglomeration of total confirmed cases has been increasing over time, while that of the daily new cases shows much more obvious in the mid-stage; and (4) timely release of the first-level public health emergency response can accelerate the emergence of the epidemic inflection point. The above analysis results have a specific reference value for the government's policy-making and measures to face public health emergencies.


Assuntos
COVID-19 , China , Cidades , Humanos , SARS-CoV-2 , Análise Espaço-Temporal
13.
Neuro Oncol ; 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33908609

RESUMO

BACKGROUND: Pituitary neuroendocrine tumors (PitNETs) are the second most common intracranial tumor. We lacked a comprehensive understanding of the pathogenesis and heterogeneity of these tumors. METHODS: We performed high-precision single-cell RNA sequencing for 2,679 individual cells obtained from 23 surgically resected samples of the major subtypes of PitNETs from 21 patients. We also performed single-cell multi-omics sequencing for 238 cells from 5 patients. RESULTS: Unsupervised clustering analysis distinguished all tumor subtypes, which was in accordance with the classification based on immunohistochemistry and provided additional information. We identified three normal endocrine cell types: somatotrophs, lactotrophs and gonadotrophs. Comparisons of tumor and matched normal cells showed that differentially expressed genes of gonadotroph tumors were predominantly downregulated, while those of somatotroph and lactrotroph tumors were mainly upregulated. We identified novel tumor-related genes, such as AMIGO2, ZFP36, BTG1 and DLG5. Tumors expressing multiple hormone genes showed little transcriptomic heterogeneity. Furthermore, single-cell multi-omics analysis demonstrated that the tumor shad a relatively uniform pattern of genome with slight heterogeneity in copy number variations. CONCLUSIONS: Our single-cell transcriptome and single-cell multi-omics analyses provide novel insights into the characteristics and heterogeneity of these complex neoplasms for the identification of biomarkers and therapeutic targets.

14.
Aging (Albany NY) ; 13(8): 11352-11362, 2021 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-33833133

RESUMO

BACKGROUND: Three polymorphisms in the Methylenetetrahydrofolate reductase (MTHFR) gene (C677T, A1298C, and A1793G) were reported associated with AD. However, their genotype distributions and associations with age at onset (AAO), homocysteine, and white matter lesions (WML) were unclear in the Chinese AD population. METHOD: We determined the presence of C677T, A1298C, and A1793G polymorphisms in the MTHFR gene using Sanger sequencing in a Chinese cohort comprising 721 AD patients (318 early-onset AD patients (EOAD) and 403 late-onset AD patients (LOAD)) and 365 elderly controls. Additionally, the homocysteine level and WML were evaluated in 121 AD patients. RESULTS: The frequency of allele T of C677T polymorphism was significantly higher in AD patients than in controls (P = 0.040), while no statistical difference was observed in A1298C and A1793G (P > 0.05). Besides, genotype distributions of C677T and A1298C polymorphisms statistically varied between AD patients and controls (P = 0.021, P = 0.012). Moreover, the AAO was significantly lower in CT/TT (C677T) genotypes carriers (P = 0.042) and higher in AC/CC (A1298C) and AG/GG (A1793G) genotypes carriers (P = 0.034, P = 0.009) in patients with LOAD. We also found that patients with CT/TT (C677T) genotypes were prone to present an increased homocysteine level (P = 0.036) and higher Fazekas score (P = 0.024). In comparison, patients with AG/GG genotypes (A1793G) had a significantly lower Fazekas score (P = 0.013). CONCLUSIONS: The genotype distributions of C677T and A1298C polymorphisms are associated with AD in the Chinese population. Moreover, AD patients with C677T polymorphism are prone to present an earlier onset, higher homocysteine level, and more severe WML.


Assuntos
Doença de Alzheimer/genética , Predisposição Genética para Doença , Homocisteína/sangue , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Substância Branca/patologia , Idade de Início , Idoso , Alelos , Doença de Alzheimer/sangue , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/patologia , Apolipoproteínas E/genética , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , China/epidemiologia , Feminino , Homocisteína/metabolismo , Humanos , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
15.
Front Genet ; 12: 583695, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33692822

RESUMO

Background: Vitamin D insufficiency has been considered a risk factor for Alzheimer's disease (AD) in several studies. Recently, four single-nucleotide polymorphisms (SNPs) to be genome-wide significant for 25-hydroxyvitamin D [25(OH)D] were identified to have an association with the risk of AD. These include GC rs2282679 A>C, CYP2R1 rs10741657 T>C, DHCR7 rs12785878 T>C, and CYP24A1 rs6013897 T>A. However, the association between these polymorphisms and AD susceptibility in the Chinese population remains unclear. Methods: A case-control cohort study was conducted in 676 AD patients (mean age at onset was 69.52 ± 10.90 years, male: 39.2%) and 551 healthy controls (mean age was 67.73 ± 6.02 years, male: 44.8%). Genotyping was determined by PCR and SNaPshot sequencing. To determine whether the four SNPs account for risks in AD in Chinese population, multivariate logistic regression models were performed. Stratified analysis was performed based on gender and age of onset of AD, separately. Statistical significance was set at 0.0125 (0.05/4) based on Bonferroni correction. Findings: DHCR7 rs12785878 T>C was found to be significantly associated with an increased risk of early-onset Alzheimer's disease (EOAD) (n = 300, risk allele C, adjusted OR = 1.542, adjusted 95% CI = 1.176-2.023, p = 0.002). There was no statistical significance of the other three SNPs between the two groups. Interpretation: Our results suggested that DHCR7 rs12785878 T>C might be associated with an increased risk of EOAD in the Chinese population, while other polymorphisms related to vitamin D insufficiency might not be. However, due to the limited data in this study, replication studies in a larger sample are required.

16.
Rev Sci Instrum ; 92(2): 025110, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648143

RESUMO

Contact electrical resistance is a critical issue to be addressed in thermoelectric modules. A commercial instrument in thermoelectricity is demonstrated for the first time to extract the contact resistivity of thermoelectric legs by use of the three options of the probe distance. The specimen comprises two legs of bismuth telluride that are connected with reflow soldering. The probe distances are calibrated with a homogeneous sample of constantan. The linear fittings between the electrical resistance and the probe gap are employed in the calibration and in deriving the contact resistivity. The contact resistivity of n-type Bi2Te3 and p-type Bi2Te3 with nickel plating to the Sn64Bi35Ag1 solder is determined to be 17.4 µΩ cm2 and 9.8 µΩ cm2 at ambient temperature, respectively. The contact resistivities at two other temperatures are extracted as well so that the contact resistivity as a function of temperature would be available from the proposed method.

17.
Science ; 371(6531): 830-834, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33602853

RESUMO

Thermoelectric technology generates electricity from waste heat, but one bottleneck for wider use is the performance of thermoelectric materials. Manipulating the configurational entropy of a material by introducing different atomic species can tune phase composition and extend the performance optimization space. We enhanced the figure of merit (zT) value to 1.8 at 900 kelvin in an n-type PbSe-based high-entropy material formed by entropy-driven structural stabilization. The largely distorted lattices in this high-entropy system caused unusual shear strains, which provided strong phonon scattering to largely lower lattice thermal conductivity. The thermoelectric conversion efficiency was 12.3% at temperature difference ΔT = 507 kelvin, for the fabricated segmented module based on this n-type high-entropy material. Our demonstration provides a paradigm to improve thermoelectric performance for high-entropy thermoelectric materials through entropy engineering.

18.
Polymers (Basel) ; 13(3)2021 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-33498926

RESUMO

Hydrogels are crosslinked polymers that become fully swollen when placed in aqueous environments. They are widely used in the field of firefighting because they can remarkably increase the viscosity and wettability of water. In this study, a thermosensitive hydrogel used to effectively suppress class A fire was synthesized by using methylcellulose, sodium polyacrylate, and magnesium chloride. The structure, surface activity and viscosity of the hydrogel were characterized. Fire extinguishing performance was evaluated based on small-scale and large-scale experiments. The results showed that a phase transition of the hydrogel occurred when the temperature rose from 50 °C to 80 °C. After the phase transition, the hydrogel showed a higher viscosity and lower surface tension, which was conducive to attach to the surface of the burning material and acting as an effective barrier to isolate oxygen. The small-scale fire extinguishing tests indicated that the concentration of the hydrogel solution has an eminent influence on fire extinguishing performance. The optimum concentration for extinguishing performance was around 6 wt%. The large-scale experiments demonstrated that the fire-extinguishing performance of this thermosensitive hydrogel was superior to the two other commercial water-based fire extinguishing agents, as it prevented re-ignition highly efficiently.

19.
Cell Res ; 31(4): 463-477, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32884136

RESUMO

Proper development of fetal germ cells (FGCs) is vital for the precise transmission of genetic and epigenetic information through generations. The transcriptional landscapes of human FGC development have been revealed; however, the epigenetic reprogramming process of FGCs remains elusive. Here, we profiled the genome-wide DNA methylation and chromatin accessibility of human FGCs at different phases as well as gonadal niche cells at single-cell resolution. First, we found that DNA methylation levels of FGCs changed in a temporal manner, whereas FGCs at different phases in the same embryo exhibited comparable DNA methylation levels and patterns. Second, we revealed the phase-specific chromatin accessibility signatures at the promoter regions of a large set of critical transcription factors and signaling pathway genes. We also identified potential distal regulatory elements including enhancers in FGCs. Third, compared with other hominid-specific retrotransposons, SVA_D might have a broad spectrum of binding capacity for transcription factors, including SOX15 and SOX17. Finally, using an in vitro culture system of human FGCs, we showed that the BMP signaling pathway promoted the cell proliferation of FGCs, and regulated the WNT signaling pathway by orchestrating the chromatin accessibility of its ligand genes. Our single-cell epigenomic atlas and functional assays provide valuable insights for understanding the strongly heterogeneous, unsynchronized, yet highly robust nature of human germ cell development.

20.
Front Aging Neurosci ; 12: 581524, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192475

RESUMO

Amyloid protein deposition is a common mechanism of hereditary amyloidosis (HA) and Alzheimer's disease (AD). Mutations of gelsolin (GSN), cystatin C (CST3), transthyretin (TTR), and integral membrane protein 2B (ITM2B) genes can lead to HA. But the relationship is unclear between these genes and AD. Genes targeted sequencing (GTS), including GSN, CST3, TTR, and ITM2B, was performed in a total of 636 patients with clinical AD and 365 normal controls from China. As a result, according to American College of Medical Genetics and Genomics (ACMG) guidelines, two novel likely pathogenic frame-shift mutations (GSN:c.1036delA:p.K346fs and GSN:c.8_35del:p.P3fs) were detected in five patients with AD, whose initial symptom was memory decline, accompanied with psychological and behavioral abnormalities later. Interestingly, the patient with K346fs mutation, presented cerebral ß-amyloid protein deposition, had an early onset (48 years) and experienced rapid progression, while the other four patients with P3fs mutation had a late onset [(Mean ± SD): 69.50 ± 5.20 years] and a long course of illness [(Mean ± SD): 9.24 ± 4.86 years]. Besides, we also discovered 17 variants of uncertain significance (VUS) in these four genes. To our knowledge, we are the first to report AD phenotype with GSN mutations in patients with AD in the Chinese cohort. Although mutations in the GSN gene are rare, it may explain a small portion of clinically diagnosed AD.

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