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2.
Heredity (Edinb) ; 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888874

RESUMO

Domesticates are an excellent model for understanding biological consequences of rapid climate change. Maize (Zea mays ssp. mays) was domesticated from a tropical grass yet is widespread across temperate regions today. We investigate the biological basis of temperate adaptation in diverse structured nested association mapping (NAM) populations from China, Europe (Dent and Flint) and the United States as well as in the Ames inbred diversity panel, using days to flowering as a proxy. Using cross-population prediction, where high prediction accuracy derives from overall genomic relatedness, shared genetic architecture, and sufficient diversity in the training population, we identify patterns in predictive ability across the five populations. To identify the source of temperate adapted alleles in these populations, we predict top associated genome-wide association study (GWAS) identified loci in a Random Forest Classifier using independent temperate-tropical North American populations based on lines selected from Hapmap3 as predictors. We find that North American populations are well predicted (AUC equals 0.89 and 0.85 for Ames and USNAM, respectively), European populations somewhat well predicted (AUC equals 0.59 and 0.67 for the Dent and Flint panels, respectively) and that the Chinese population is not predicted well at all (AUC is 0.47), suggesting an independent adaptation process for early flowering in China. Multiple adaptations for the complex trait days to flowering in maize provide hope for similar natural systems under climate change.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33835792

RESUMO

Structure and dielectric properties of gillespite-type ceramics ACuSi4O10 (A = Ca, Sr, Ba) were investigated by crystal structure refinement, far-infrared reflectivity spectroscopy, and microwave dielectric measurements. A series of (CaxSr1-x)CuSi4O10 (0 < x < 1) ceramics with relative permittivities of 5.70-5.82, Q × f values of 20391-48794 GHz (@ ∼ 13.5 GHz), and τf of -46.3 to -38.9 ppm/°C were synthesized. By Ca2+ substitution for Sr2+ at the A-site, the rigid double-layered copper silicate framework remains stable, resulting in the nearly unchanged relative permittivity, while the [(Ca,Sr)O8] dodecahedron undergoes shrinkage and distortion, which is correlated to the changes in the Q × f and τf values. The normalized bond valence sums indicate that almost all ions are rattling, weakening the bond strengths and enlarging the molecular dielectric polarizability. The fitting of far-infrared reflectivity spectra reveals that the local structure changes suppress the intermediate and low-frequency vibrational modes significantly and improves the contribution from electronic polarization to permittivity. Symmetry breaking of the [(Ca,Sr)O8] dodecahedron conforms to the elevated restoring forces acting on the ions and improves the τf value. The large span in Q × f value may have intricate correlations to local structure changes and defects. Machine learning methods were introduced to explore the decisive structural factors for the Q × f value. A Q × f value prediction model correlated with the A-O2 bond length and the variance of A-O bond lengths was established. The Q × f values of isostructural (BaySr1-y)CuSi4O10 ceramics were predicted and verified by experiments.

4.
BMC Cancer ; 21(1): 433, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879096

RESUMO

BACKGROUND: Inositol polyphosphate 4-phosphatase type II (INPP4B) is a negative regulator of the PI3K-Akt signalling pathway and plays a contradictory role in different types of cancers. However, the its biological role played by INPP4B in human gallbladder cancer (GBC) has not been elucidated. In this study, we investigated the expression, clinical significance and biological function of INPP4B in GBC patients and cell lines. METHODS: The INPP4B protein expression levels in gallbladder cancer tissues and normal gallbladder tissues were detected by immunohistochemistry, and the clinical significance of INPP4B was analysed. Knockdown and overexpression of INPP4B in GBC-SD and SGC-996 cells followed by cell proliferation, clonogenic, apoptosis detection, scratch wound-healing and transwell assays were used to identify INPP4B function in vitro. RESULTS: INPP4B was up-regulated in human GBC tissues compared with normal gallbladder tissues and was related to histopathological differentiation (p = 0.026). Here, we observed that INPP4B was highly expressed in high-moderately differentiated tumours compared with low-undifferentiated tumours (p = 0.022). Additionally, we found that INPP4B expression was not associated with overall survival of GBC patients (p = 0.071) and was not an independent prognostic factor. Furthermore, when we stratified the relationship between INPP4B expression and the prognosis of GBC based on histopathological differentiation, we found that INPP4B played a contradictory role in GBC progression depending on the degree of differentiation. In addition, INPP4B knockdown inhibited the proliferation, colony formation, migration and invasion in GBC cells, while INPP4B overexpression had the opposite effects in vitro, which indicates its role as an oncoprotein. CONCLUSIONS: These findings suggested that INPP4B may play a dual role in the prognosis of GBC depending on the degree of differentiation and that INPP4B might act as an oncogene in gallbladder cancer cells.

5.
J Int Med Res ; 49(4): 3000605211006522, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33823642

RESUMO

OBJECTIVE: To explore the relationship between the omentin-1 gene rs2274907 A>T polymorphism and colorectal cancer (CRC) in the Chinese Han population. METHODS: rs2274907 A>T was assessed by PCR-restriction fragment length polymorphism analysis. Plasma omentin-1 expression from 358 patients with CRC and 286 healthy controls was analyzed by enzyme-linked immunosorbent assay. CRC and control groups were divided into subgroups according to the body mass index (BMI) threshold of 25 kg/m2. RESULTS: No significant differences were observed between CRC and control groups in terms of genotype or allele frequencies of rs2274907 A>T. Compared with individuals with BMI <25 kg/m2 and the rs2274907 TT genotype, those with AA+AT genotypes and BMI ≥25 kg/m2 had a 3.027-fold increased risk of CRC. A significant tendency toward a higher stage of colorectal adenocarcinomas and depth of invasion was observed in individuals with the rs2274907 AA genotype compared with other genotypes. CONCLUSIONS: The omentin-1 gene rs2274907 A>T polymorphism does not seem to play a critical role in the development of CRC in the Chinese Han population, but an interaction between the rs2274907 A allele and BMI may increase the CRC risk. The rs2274907 AA genotype is a potential biomarker for CRC stage progression.


Assuntos
Neoplasias Colorretais , Citocinas , Lectinas , Polimorfismo de Nucleotídeo Único , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , China , Neoplasias Colorretais/genética , Citocinas/genética , Feminino , Proteínas Ligadas por GPI/genética , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Lectinas/genética , Masculino , Polimorfismo de Nucleotídeo Único/genética
6.
Updates Surg ; 73(2): 597-605, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33576931

RESUMO

This study evaluated the impact of a new intracorporeal π-shaped esophagojejunostomy (EJS) and double-tract reconstruction (DTR) in totally laparoscopic and totally robotic proximal gastrectomy (TLPG or TRPG) for treating upper third early gastric cancer (U-EGC) in terms of intraoperative and short-term postoperative outcomes. Early proximal gastric cancer patients were identified based on a prospectively established database. From January 2017 to December 2018, these patients underwent intracorporeal π-shaped EJS and DTR after totally laparoscopic (n = 8) or robotic (n = 4) proximal gastrectomy (PG). We recorded and analyzed the baseline characteristics and surgical outcomes, including postoperative complications for these patients. No severe postoperative complications were observed following the operational procedures. Twelve patients (seven male and five female) diagnosed with cardia cancer (Siewert II and III) were enrolled, of which eight underwent the totally laparoscopic proximal gastrectomy (TLPG), and four underwent the totally robotic proximal gastrectomy (TRPG). The mean operative time, blood loss, day of the start of the diet, and postoperative hospital stay was 235.54 ± 20.79 min, 50.65 ± 35.44 mL, 3.85 ± 0.65 days, and 12.45 ± 3.24 days, respectively. All patients presented with a diagnosis of stage I gastric cancer. The mean number of lymph node dissections and the maximum tumor diameter was 13.91 ± 4.63 and 2.18 ± 0.73 cm, respectively. After the operational procedure, using the iodoethylene contrast reagent, we observed that a large proportion of iodoethylene contrast agents entered the jejunum directly, and a small proportion entered the jejunum through the duodenum. Surgeons followed up with ten patients for more than 12 months and the remaining two patients for more than 24 months. None of the patients showed any signs of anastomotic stenosis or reflux esophagitis or anemia symptoms. This study presents a novel method for π-shaped EJS and DTR as an alternative in TLPG or TRPG for treating proximal early gastric cancer, and it offers better short-term postoperative and intraoperative surgical outcomes.

8.
J Mol Med (Berl) ; 99(2): 193-212, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33392633

RESUMO

Although gastric cancer (GC) is one of the most common cancers with high incidence and mortality rates, its pathogenesis is still not elucidated. GC carcinogenesis is complicated and involved in the activation of oncoproteins and inactivation of tumor suppressors. The ubiquitin-proteasome system (UPS) is crucial for protein degradation and regulation of physiological and pathological processes. E3 ubiquitin ligases are pivotal enzymes in UPS, containing various subfamily proteins. Previous studies report that some E3 ligases, including SKP2, CUL1, and MDM2, act as oncoproteins in GC carcinogenesis. On the other hand, FBXW7, FBXL5, FBXO31, RNF43, and RNF180 exert as tumor suppressors in GC carcinogenesis. Moreover, E3 ligases modulate cell growth, cell apoptosis, and cell cycle; thus, it is complicated to confer cisplatin resistance/sensitivity in GC cells. The intrinsic and acquired cisplatin resistance limits its clinical application against GC. In this review, we explore oncogenic and tumor suppressive roles of E3 ligases in GC carcinogenesis and focus on the effects of E3 ligases on cisplatin resistance in GC cells, which will provide novel therapeutic targets for GC therapy, especially for cisplatin-resistant patients.

9.
J Mol Model ; 27(1): 4, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33387061

RESUMO

External electric field has been regarded as an effective tool to induce the variation of melting points of molecular crystals. The melting point of 2,4,6-trinitrotoluene (TNT) was calculated by molecular dynamics simulations under external electric field, and the electric field effects on the cooperativity effects of the ternary (TNT)3 were investigated at the M06-2X/6-311+G(d) and ωB97X-D/6-311++G(2d,p) levels. The results show that the melting points are decreased while the intermolecular interactions are strengthened under the external electric fields, suggesting that the intermolecular interactions cannot be used to explain the decreased melting points. A deduction based on the cooperativity effect is put forward: the enhanced cooperativity effects create the more serious defects in the melting process of the molecular crystal under the external electric fields, and simultaneously the local order parameters are decreased, leading to the decreased melting point. Thus, the cooperativity effect stemmed from the intermolecular C-H∙∙∙O H-bonding interactions controls the change of TNT melting point under the external electric field. Employing the information-theoretic approach (ITA), the origin of the cooperativity effects on the melting points of molecular crystal is revealed. This study opens a new way to challenge the problems involving the melting points for the molecular crystal under the external electric fields. However, note that above deduction needs to be improved; after all, the simple (TNT)3 model cannot replace the crystal structure.

10.
Plant Dis ; 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33439037

RESUMO

Alfalfa (Medicago sativa L.) is one of the most important perennial leguminous forages in many countries, known by its high feed value and yield potential. With the increasing demand for feed, alfalfa has been planted all over China. However, an increasingly serious alfalfa disease was observed and may restrict the development of the alfalfa industry in North China. In August 2019, an emerging alfalfa disease with symptoms resembling southern blight was observed in Jiaozhou experimental base (Jiaozhou Modern Agricultural Science and Technology Demonstration Park) of Qingdao Agricultural University (Qindao, Shandong province, China). The infected plants showed dark brown lesions on the stems and yellowing and wilting of the leaves. The pathogen produced white fluffy mycelia, and later sclerotia on stems and roots; the disease affected up to 25% of the plants and causes bare spots filled with weeds (Figure S1). Typical symptomatic tissues were brought back to the laboratory for pathogen isolation and identification. Fragments (3-5mm2) of root tissues were excised from lesions on the symptomatic roots and their surfaces were disinfested by sequential dipping in 70% ethanol for 30 s and in 2% NaClO for 3 min, then the fragments were rinsed in sterile water five times and cultured on potato dextrose (PDA) medium amended with streptomycin sulfate (0.1mg/mL). Cultures were incubated at 28°C in the dark and purified in PDA medium for three times. A representative strain (coded as CZL1) was isolated from the root rot of the diseased plant. After four days incubation on PDA, CZL1 formed white fluffy aerial mycelium 5.6-6 cm in diameter typical of S. rolfsii. After 15 to 20 days, abundant round sclerotia approximately1-3 mm in diameter were produced on the surface of the culture (Figure S2). The sclerotia were white at first and then gradually turned dark brown. To confirm the identity of the causal fungus, the complete internal transcribed spacer (ITS) rDNA region of the fungus was amplified using the primers ITS1/ITS4 (White et al.1990), and the elongation factor-1a gene (EF1a) was amplified using primers EF1-983F/EF1-2218R (Rehner and Buckley 2005). Then the PCR amplicons were cloned into the pCE2 TA/Blunt-Zero vector. The isolate was determined to contain two distinct sequence types for each gene. The results of ITS (MT812692, MT812693) and EF1a (MT846496 and MT846497) sequences were deposited in GenBank. DNA analysis revealed that the two ITS sequences were more than 99% identical to Athelia rolfsii (MN872304) in the NCBI GenBank database, and two EF1a sequences were 99% identical to the A. rolfsii EF1a sequence MN702789 and KP982854. To fulfill Koch's postulates, infected sorghum grain was placed near the roots of 15 40-day-old healthy alfalfa seedlings split into 3 pots with the same number of seedlings receiving a control treatment of sterilized sorghum grain. All plants were incubated in growth chamber at 24±1°C with 14-h-photoperiod (85% relative humidity). After 10-15 days, blight symptoms identical to those in the field were observed on inoculated plants, whereas those control plants were symptomless (Figure S2). S. rolfsii was successfully re-isolated from the inoculated plants and molecularly characterized as described above. Based on disease symptoms, fungal colonies, the ITS and EF1a sequence, and pathogenicity to the host, this fungus was identified as S. rolfsii (teleomorph Athelia rolfsii). To our knowledge, this is the first report of S. rolfsii as the causal agent of southern blight of alfalfa in North China, and it is also the first report of southern blight on alfalfa caused by S. rolfsii in China since 1996 observed in Guizhou province (Mo and Luo 1996).

11.
Future Oncol ; 17(5): 529-539, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33401980

RESUMO

Aim: This initial study was conducted with the aim of constructing an accurate nomogram for gastric marginal zone lymphoma patients. Methods: Data from 4414 patients diagnosed with gastric mucosa-associated lymphoid tissue lymphoma from 2004 to 2015 were retrieved from the Surveillance, Epidemiology and End Results database. Multivariate analyses were conducted for the construction of the nomogram. Results: Age, sex, race, marital status, Ann Arbor stage and radiotherapy were significantly associated with overall survival, while age, marital status, Ann Arbor stage, surgery, chemotherapy and radiotherapy were independent prognostic predictors of cause-specific survival. Stratified analysis indicated that radiotherapy alone resulted in better overall survival and cause-specific survival than chemotherapy alone. However, the present study also has several limitations; for example, patients' Helicobacter pylori infection status and the chemotherapy regimen used were unknown. Conclusion: This study constructed and validated an accurate prognostic nomogram for gastric mucosa-associated lymphoid tissue lymphoma patients.

12.
Infect Genet Evol ; 89: 104681, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33333289

RESUMO

BACKGROUND: Sepsis and subsequent multiple organ dysfunction syndrome (MODS) have high global incidence and mortality rate, imposing tremendous health burden. microRNAs (miRNAs or miRs) are implicated in the pathogenesis of sepsis and MODS. The aim of this study is to explore the potential mechanisms of miR-103a-3p targeted high mobility group box 1 (HMGB1) involvement in the pathogenesis of sepsis complicated with multiple organ dysfunction syndrome (MODS). METHODS: A mouse sepsis model was induced by lipopolysaccharide (LPS). Bone marrow-derived macrophages were collected and LPS was used to establish a cellular inflammation model. Targeted binding between miR-103a-3p and HMGB1 was verified by a double luciferase assay and their roles in LPS-induced sepsis were further explored using gain-of-function experiments. RESULTS: miR-103a-3p was decreased while HMGB1 was increased in sepsis. In LPS-induced mouse sepsis models, the downregulation of HMGB1 was found to result in reductions in NO, TNF-α, IL-1ß, IL-6, lung myeloperoxidase activity, pulmonary microvascular albumin leakage, serum alanine aminotransferase, aspartate aminotransferase activity, and lung and liver tissue apoptosis. Additionally, decreased HMGB1 blunted the inflammatory response and increased survival rate of modeled mice. Importantly, HMGB1 was confirmed to a target gene of miR-103a-3p. In cellular inflammation models, miR-103a-3p was found to alleviate LPS-induced sepsis and MODS in vitro by decreasing HMGB1. CONCLUSIONS: Taken together, our results demonstrated the inhibitory role of miR-103a-3p in sepsis via inhibiting HMGB1 expression.

13.
Surg Endosc ; 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33237468

RESUMO

BACKGROUND: Robotic colorectal cancer surgery is widely accepted and applied. However, there is still no objective and comprehensive assessment on the data of nationwide multicenter series. METHOD: A total of 28 medical centers in Mainland China participated in this nationwide retrospective observational study. From the first case performed in each center to the last until December 2017, patients with robotic resection for primary tumor and pathologically confirmed colorectal adenocarcinoma were consecutively enrolled. Clinical, pathological and follow-up data were collected and analyzed. RESULTS: A total of 5389 eligible patients were finally enrolled in this study, composing 72.2% of the total robotic colorectal surgery volume of Mainland China in the same period. For resections of one bowel segment of primary tumor, the postoperative mortality rate was 0.08% (4/5063 cases), and the postoperative complication rate (Clavien-Dindo grade II or higher) was 8.6% (434/5063 cases). For multiple resections, the postoperative mortality rate was 0.6% (2/326 cases), and the postoperative complication rate was 16.3% (53/326 cases). Out of 2956 patients receiving sphincter-preserving surgery in only primary resection, 130 (4.4%) patients had anastomotic leakage. Traditional low anterior resection (tumor at middle rectum) (OR 2.384, P < 0.001), traditional low anterior resection (tumor at low rectum) (OR 1.968, P = 0.017) and intersphincteric resection (OR 5.468, P = 0.006) were significant independent risk factors for anastomotic leakage. Female gender (OR 0.557, P = 0.005), age ≥ 60 years (OR 0.684, P = 0.040), and preventive stoma (OR 0.496, P = 0.043) were significant independent protective factors. Body mass index, preoperative chemotherapy/radiotherapy, tumor size, and TNM stage did not independently affect the occurrence of anastomotic leakage. CONCLUSION: Robotic colorectal cancer surgery was safe and reliable and might have advantages in patients at high risk of anastomotic leakage.

14.
J Mol Model ; 26(12): 351, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33241433

RESUMO

Controlling the selectivity of detonation initiation reaction to reduce the explosive sensitivity has been a Holy Grail in the field of energetic materials. The effects of the external electric fields on the homolysis of the N-NO2 bond and initiation reaction dynamics of NH2NO2∙∙∙H2O (i.e., intermolecular and 1,3-intramolecular hydrogen transfers) were investigated at the MP2/6-311++G(2d,p) and CCSD/6-311++G(2d,p)//MP2/6-311++G(2d,p) levels. The results show that the N-NO2 bond is not the "trigger linkage." The notable transiliences of the activation energy of the intermolecular hydrogen transfer are found with the field strength of - 0.012 a.u. along the -x-direction, leading to the conversion of the main reaction between the intermolecular and 1,3-intramolecular hydrogen transference. The activation energies of two kinds of the hydrogen transferences are increased under the external electric fields along the -y-direction. In particular, due to the conversion of the main reaction, the activation energies of the overall reaction are increased significantly along the -x-direction, leading to the significant reduced explosive sensitivities. Therefore, by controlling the field strengths and orientations between the "reaction axis" and external electric field along the y- and x-directions, the selectivity of the initiation reaction could be controlled and the explosive sensitivity could be reduced. Employing AIM (atoms in molecules) and surface electrostatic potentials, the origin of the control of reaction selectivity and the reduction of sensitivity is revealed. This work is of great significance to the improvement of the technology that the external electric fields are added safely into the energetic material system to enhance the explosive performance. Graphical abstract.

15.
Sci Adv ; 6(46)2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33188021

RESUMO

East Asian monsoon variability in the Pliocene warm world has not been sufficiently studied because of the lack of direct records. We present a high-resolution precipitation record from Pliocene fluvial-lacustrine sequences in the Weihe Basin, Central China, a region sensitive to the East Asian monsoon. The record shows an abrupt monsoon shift at ~4.2 million years ago, interpreted as the result of high-latitude cooling, with an extratropical temperature decrease across a critical threshold. The precipitation time series exhibits a pronounced ~100-thousand year periodicity and the presence of precession and half-precession cycles, which suggest low-latitude forcing. The synchronous phase but mismatched amplitudes of the East Asian monsoon precipitation proxy and eccentricity suggest a nonlinear but sensitive precipitation response to temperature forcing in the Pliocene warm world. These observations highlight the role of high- and low-latitude forcing of East Asian monsoon variations on tectonic and orbital time scales.

16.
Oncol Lett ; 20(6): 386, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33193846

RESUMO

Dysregulated microRNAs (miRNAs) serve vital roles in the progression and prognosis of breast cancer. miR-623 has been reported to influence the progression of numerous other cancers, such as lung adenocarcinoma and hepatocellular carcinoma, however, its role in breast cancer remains unclear. In the present study, the mRNA expression of miR-623 was studied in 121 pairs of breast cancer and adjacent normal tissues and cultured cell lines by reverse-transcription quantitative PCR. The association between miR-623 expression and clinical characteristics or the overall survival rate of patients was investigated by the χ2 test or Cox regression analysis, respectively. The role of miR-623 in cell proliferation, migration and invasion of breast cancer cells was evaluated by cell transfection to regulate miR-623 expression and the CCK8 and Transwell assays, respectively. miR-623 was downregulated in breast cancer tissues and cell lines compared with normal tissues and breast epithelial cell lines. The χ2 test demonstrated that the downregulation of miR-623 was associated with the tumor node metastasis (TNM) stage of patients with breast cancer. miR-623 and TNM stage were considered as two independent prognostic factors for breast cancer. Additionally, cell proliferation, migration, and invasion of breast cancer cells were promoted by the downregulation of miR-623, while upregulation of miR-623 led to inhibition of the aforementioned processes. Downregulation of miR-623 in breast cancer is associated with the development of breast cancer and indicates a poor prognosis of patients. The downregulation of miR-623 promotes cell proliferation, migration and invasion of breast cancer. The findings of the present study indicate that miR-623 functions as a prognosis biomarker and a tumor suppressor in breast cancer, which provides a potential therapeutic target for patients with breast cancer.

17.
ACS Appl Mater Interfaces ; 12(46): 51662-51668, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33140968

RESUMO

The emergence of piezoelectric properties in two-dimensional (2D) layered transition metal dichalcogenides (TMDs) has triggered the intensive research on using low dimensional materials for conversion of mechanical stimuli into electrical signals or vice versa. While the bulk intrinsically presents no piezoelectric property, the origin of the piezoelectric responses in their 2D thin planes is ascribed to the loss of centrosymmetry. There are also other categories of 2D layered materials such as post-transition metal dichalcogenides (PTMDs) that might be of interests, which have been confirmed theoretically and are yet to be fully explored experimentally. In this work, we investigate the thickness-dependent piezoelectric responses of 2D tin disulfide (SnS2) nanosheets as a representative of layered PTMDs. The results indicate that the 2D SnS2 nanosheets with a thickness of ∼4 nm present an effective out-of-plane piezoelectric response of 2 ± 0.22 pm/V. Furthermore, the thickness dependence of the piezoelectric behavior at a resonant frequency shows that the piezoelectric coefficient decreases with increasing the thickness of 2D SnS2 nanosheets. Additionally, in reference to periodically poled lithium niobate piezoelectric crystal, the measured effective lateral piezoelectric coefficients at different voltages range from 0.61 to 1.55 pm/V with the average value at ∼1 pm/V. This study expands candidates for new piezoelectric materials in the 2D domain with comparable vertical and lateral coefficients, potentially opening a broader horizon for integration into sensors, actuators, and micro- and nanoelectromechanical systems.

18.
BMC Plant Biol ; 20(1): 490, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33109077

RESUMO

BACKGROUND: Kernel row number (KRN) is an important trait for the domestication and improvement of maize. Exploring the genetic basis of KRN has great research significance and can provide valuable information for molecular assisted selection. RESULTS: In this study, one single-locus method (MLM) and six multilocus methods (mrMLM, FASTmrMLM, FASTmrEMMA, pLARmEB, pKWmEB and ISIS EM-BLASSO) of genome-wide association studies (GWASs) were used to identify significant quantitative trait nucleotides (QTNs) for KRN in an association panel including 639 maize inbred lines that were genotyped by the MaizeSNP50 BeadChip. In three phenotyping environments and with best linear unbiased prediction (BLUP) values, the seven GWAS methods revealed different numbers of KRN-associated QTNs, ranging from 11 to 177. Based on these results, seven important regions for KRN located on chromosomes 1, 2, 3, 5, 9, and 10 were identified by at least three methods and in at least two environments. Moreover, 49 genes from the seven regions were expressed in different maize tissues. Among the 49 genes, ARF29 (Zm00001d026540, encoding auxin response factor 29) and CKO4 (Zm00001d043293, encoding cytokinin oxidase protein) were significantly related to KRN, based on expression analysis and candidate gene association mapping. Whole-genome prediction (WGP) of KRN was also performed, and we found that the KRN-associated tagSNPs achieved a high prediction accuracy. The best strategy was to integrate all of the KRN-associated tagSNPs identified by all GWAS models. CONCLUSIONS: These results aid in our understanding of the genetic architecture of KRN and provide useful information for genomic selection for KRN in maize breeding.

19.
Onco Targets Ther ; 13: 10607-10619, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116638

RESUMO

Background: Gastric cancer (GC) is one of the deadliest cancer worldwide. Multiple long non-coding RNAs (lncRNAs) are recently identified as crucial oncogenic factors or tumor suppressors in GC. In this study, we aimed to probe into the effect of LINC01436 on GC progression. Methods: LINC01436 and miR-513a-5p expressions in GC tissue samples were measured using quantitative real-time polymerase chain reaction (qRT-PCR). Western blot was used to detect the expression of apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1) expression. Human GC cell lines AGS and BGC-823 were employed to investigate the function and mechanism of LINC01436 in GC. Cell counting kit-8 (CCK-8) assay was used to assess the effect of LINC01436 on proliferation. Flow cytometry was utilized to explore the effect of LINC01436 on apoptosis, and Transwell assay was conducted to detect the effect of LINC01436 on the migration and invasion. Colony formation assay was performed to evaluate the effect of LINC01436 on radioresistance of GC cells. Furthermore, luciferase reporter assay and RNA immunoprecipitation assay were conducted to confirm the binding relationship between miR-513a-5p and LINC01436. Additionally, Western blot was used to study the regulatory function of LINC01436 and miR-513a-5p on APE1. Results: LINC01436 expression of GC clinical samples was remarkably increased and LINC01436 was correlated with unfavorable pathological indexes. LINC01436 high expression was associated with shorter overall survival time. Its overexpression observably promoted the proliferation, metastasis and radioresistance of GC cells, and its knockdown suppressed the malignant phenotypes of GC cells. LINC01436 overexpression markedly reduced the miR-513a-5p expression via sponging it and enhanced the APE1 expression. MiR-513a-5p overexpression or APE1 knockdown reversed the effects of LINC01436 on GC cells. Conclusion: LINC01436 is a molecular sponge of tumor suppressor miR-513a-5p, which indirectly enhances the APE1 expression and functions as the oncogenic lncRNA in GC.

20.
Adv Mater ; 32(45): e2004247, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32960475

RESUMO

Atomically thin materials face an ongoing challenge of scalability, hampering practical deployment despite their fascinating properties. Tin monosulfide (SnS), a low-cost, naturally abundant layered material with a tunable bandgap, displays properties of superior carrier mobility and large absorption coefficient at atomic thicknesses, making it attractive for electronics and optoelectronics. However, the lack of successful synthesis techniques to prepare large-area and stoichiometric atomically thin SnS layers (mainly due to the strong interlayer interactions) has prevented exploration of these properties for versatile applications. Here, SnS layers are printed with thicknesses varying from a single unit cell (0.8 nm) to multiple stacked unit cells (≈1.8 nm) synthesized from metallic liquid tin, with lateral dimensions on the millimeter scale. It is reveal that these large-area SnS layers exhibit a broadband spectral response ranging from deep-ultraviolet (UV) to near-infrared (NIR) wavelengths (i.e., 280-850 nm) with fast photodetection capabilities. For single-unit-cell-thick layered SnS, the photodetectors show upto three orders of magnitude higher responsivity (927 A W-1 ) than commercial photodetectors at a room-temperature operating wavelength of 660 nm. This study opens a new pathway to synthesize reproduceable nanosheets of large lateral sizes for broadband, high-performance photodetectors. It also provides important technological implications for scalable applications in integrated optoelectronic circuits, sensing, and biomedical imaging.

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