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Cherry tomatoes (Solanum lycopersicum) are becoming increasingly popular due to their nutrition and delicious flavor. However, cherry tomatoes are highly perishable and susceptible to various pathogenic microorganisms after harvest, such as Botrytis cinerea. In the pretest experiment, we screened out three kinds of plant essential oils (EOs) (Torreya grandis oil, Eriobotrya japonica oil, and Citrus medica oil) that have strong fungicidal activity on B. cinerea from cherry tomatoes. To further evaluate the postharvest preservation application prospect of these three oils for cherry tomatoes, the oils were extracted from different parts of three plants by hydrodistillation, and their chemical constituents were analyzed by gas chromatography-mass spectrometry. The main representative components of T. grandis oil, E. japonica oil, and C. medica oil were δ-cadinene (11.76%), transnerolidol (9.70%), and 5,7-dimethoxycoumarin (23.22%), respectively. These three EOs effectively inhibited the mycelial growth of B. cinerea in vitro, with EC50 values of 81.672, 144.046, and 221.500 µl/liter, respectively. Compared with the blank control and other oil treatments, the T. grandis oil (at a concentration of 200 µl/liter) fumigation treatment was more effective at inhibiting the growth rate of the pathogen. In addition, the phenolic content and phenylalanine ammonia lyase, ß-1,3-glucanase, chitinase, and peroxidase activities of tomatoes significantly increased on the seventh day due to the T. grandis oil treatment. The present study shows that these three oils with high extraction rates have preservation potential for cherry tomatoes. Among these three EOs, T. grandis oil can be used to further develop preservative products as a fumigant.
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Botrytis , Óleos Voláteis , Solanum lycopersicum , Frutas/química , Fumigação , Óleos Voláteis/farmacologiaRESUMO
Phosphatases are a class of enzymes catalyzing the cleavage of monophosphate ester bonds from the phosphorylated substrates. They have important applications in construction of in vitro multi-enzymatic system for monosaccharides. However, the enzymes generally show substrate ambiguity, which has become a bottleneck for efficient biosynthesis of target products with high purity. In this study, semirational design was performed on phosphatase from Thermosipho atlanticus (Ta-PST). The hotspot amino acid residues forming a "cap domain" were identified and selected for saturation mutagenesis. The mutant F179T and F179M showed improved substrate preference toward fructose-6-phosphate and mannose-6-phosphate, respectively. Coupling with other enzymes involved in the multi-enzymatic system under optimized conditions, the application of F179T led to fructose yield of 80% from 10 g/L maltodextrin and the ratio between the target product and by-product glucose was increased from 2:1 to 19:1. On the other hand, the application of F179M led to mannose yield of 59% with ratio of mannose to the by-products glucose and fructose increased from 1:1:1 to 14:2:1. Moreover, the molecular understanding of the beneficial substitution was gained by structural analysis and molecular dynamic simulations, giving important guidance to regulate the enzyme's substrate preference.
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Monossacarídeos , Monoéster Fosfórico Hidrolases , Especificidade por Substrato , Manose , Frutose , GlucoseRESUMO
In the end of the Discussion section, following information should be included.
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Hypoxia stress may affect the fish intestine and thereby threaten the growth and survival of the fish. Teprenone is a clinically effective agent in protecting gastrointestinal mucosa. This study aims to assess the effect of teprenone in the intestine of Chinese sea bass Lateolabrax maculatus under intermittent hypoxic stress. L. maculatus juveniles were either raised under intermittent hypoxic condition or normal condition (NC). Part of the hypoxic-intervened fish were treated with teprenone at different concentrations (HTs), and the rest were regarded as hypoxic control (HC). Histological analysis was performed on the epithelial tissue of the fish intestine. High-throughput sequencing technology was used to analyze the diversity and composition of the microbial community in L. maculatus intestine. Reduced villi length and goblet cell, exfoliated enterocyte, and improper arrangement of villi were observed in HC compared with NC and HTs. Proteobacteria, Firmicutes, and Bacteroidetes represented the most abundant phyla in each sample. Significantly higher microbial diversity was detected in HC compared with NC (P < 0.05). At the phylum level, HC presented significantly decreased relative abundance of Proteobacteria, and significantly increased relative abundance of Bacteroidetes, Chloroflex, and Cyanobacteria compared with NC (P < 0.05). At the class level, HC showed significantly reduced relative abundance of Alphaproteobacteria and Bacilli, and significantly increased relative abundance of Clostridia, Gammaproteobacteria, and Bacteroides (P < 0.05). Teprenone protects the intestine from epithelial damages and maintains the microbial harmony in L. maculatus under intermittent hypoxic stress.
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Antiulcerosos/farmacologia , Bass , Diterpenos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Intestinos/patologiaRESUMO
The phenolic constituents of Wikstroemia chamaedaphne were investigated by various column chromatographic methods including silica gel,Sephadex LH-20,ODS and preparative HPLC,and their chemical structures were identified by physico-chemical properties and spectral analyses. Thirteen phenolic compounds were isolated and elucidated,including five flavonoids: luteolin 7-O-ß-D-glucopyranoside(1),luteolin 4'-O-ß-D-glucopyranoside(2),kaempferol 3-O-ß-D-glucopyranoside(3),chrysoeriol 4'-O-ß-D-glucopyranoside(4),chrysoeriol(5); and eight lignans:(-)-secoisolariciresinol(6),acanthosessilin A(7),(-)-nortrachelogenin(8),(+)-isolariciresinol(9),sesamin(10),syringaresinol(11),(+)-epipinoresinol(12),and [3,3',4,4'-tetrahydro-6,6'-dimethoxy-3,3'-bi-2 H-benzopyran]-4,4'-diol(13). Compounds 1, 3, 5-8, 10, 11 and 13 were obtained from the plants of W. chamaedaphne for the first time,and compounds 1,5,7,10 and 13 were obtained from the Wikstroemia genus for the first time.
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Flavonoides/análise , Fenóis/análise , Wikstroemia/química , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Compostos Fitoquímicos/análiseRESUMO
Body weight traits are important economic characters of broilers. This study was carried out to screen for molecular markers and candidate genes that can be used to improve the body weight traits. A herd of 400 female Jinghai yellow chickens were measured for body weights from 0 to 14 weeks of age. Genome-wide association study (GWAS) was carried out using specific-locus amplified fragment sequencing (SLAF-seq) technology to detect SNPs associated with body weight traits of Jinghai yellow chicken. Finally, 100 SNPs that associated with body weight traits were detected. The results showed that effects of 15 SNPs reached 5% Bonferroni genome-wide significance and 85 SNPs reached potential genome-wide significance. Genes in the candidate regions with 1 Mb windows (SNP position±0.5 Mb) surrounding each significant SNP were screened. Finally, nine candidate genes were obtained, among which four genes of FAM124A (Family with sequence similarity 124A), QDPR (Quinoid dihydropteridine reductase), WDR1 (WD repeat domain 1) and SLC2A9 (Solute carrier family 2 (facilitated glucose transporter), member 9) might be important candidate genes influencing body weight traits of Jinghai yellow chicken. Furthermore, it was also found that most SNPs associated with mid and late growth and body weights were intensively located in the region of 75.6-80.7 Mb on chromosome 4. Our study thus provides a basis for genetic understanding of the Jinghai yellow chicken body weight traits.
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Peso Corporal/genética , Galinhas/genética , Estudo de Associação Genômica Ampla , Animais , Feminino , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Epidemiological studies suggest an association between folate deficiency (FD) and cervical squamous cell carcinoma (SCC) progression. However, the underlying mechanism is unclear. Our study showed that FD-driven downregulation of miR-375 promoted proliferation of SCC SiHa cells and progression of xenograft tumors developed from SiHa; however, the exact mechanism of this process remained unclear. The current study aimed to elucidate the underlying mechanisms by which FD promotes the progression of SiHa cells by downregulating miR-375 expression. The results showed that miR-375 acted as a suppressor of SCC and inhibited the proliferation, migration, and invasion of SiHa cells. The FZD4 gene was identified as a target gene of miR-375, which can reverse the anti-onco effect of miR-375 and promote the proliferation and migration of SiHa cells. Furthermore, the regulatory effects of miR-375 and FZD4 on SiHa cells may be achieved by activating the ß-catenin signaling pathway. Moreover, FD may regulate the expression of miR-375 by regulating its DNA methylation level in the promoter region. In conclusion, our study reveals that FD regulates the miR-375/FZD4 axis by increasing the methylation of the miR-375 promoter, thereby activating ß-catenin signaling to promote SiHa cells progression. This study may provide new insights into the role of folic acid in the prevention and treatment of SCC.
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Carcinoma de Células Escamosas , MicroRNAs , Neoplasias do Colo do Útero , Feminino , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo do Útero/genética , Via de Sinalização Wnt , Ácido Fólico/farmacologia , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular , Receptores Frizzled/genéticaRESUMO
We recently detected a HKU4-related coronavirus in subgenus Merbecovirus (named pangolin-CoV-HKU4-P251T) from a Malayan pangolin1. Here we report isolation and characterization of pangolin-CoV-HKU4-P251T, the genome sequence of which is closest to that of a coronavirus from the greater bamboo bat (Tylonycteris robustula) in Yunnan Province, China, with a 94.3% nucleotide identity. Pangolin-CoV-HKU4-P251T is able to infect human cell lines, and replicates more efficiently in cells that express human-dipeptidyl-peptidase-4 (hDPP4)-expressing and pangolin-DPP4-expressing cells than in bat-DPP4-expressing cells. After intranasal inoculation with pangolin-CoV-HKU4-P251, hDPP4-transgenic female mice are likely infected, showing persistent viral RNA copy numbers in the lungs. Progressive interstitial pneumonia developed in the infected mice, characterized by the accumulation of macrophages, and increase of antiviral cytokines, proinflammatory cytokines, and chemokines in lung tissues. These findings suggest that the pangolin-borne HKU4-related coronavirus has a potential for emerging as a human pathogen by using hDPP4.
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Infecções por Coronavirus , Coronavirus , Pangolins , Animais , Feminino , Humanos , Camundongos , China , Quirópteros , Citocinas , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Camundongos Transgênicos , Pangolins/virologiaRESUMO
Various SARS-CoV-2-related coronaviruses have been increasingly identified in pangolins, showing a potential threat to humans. Here we report the infectivity and pathogenicity of the SARS-CoV-2-related virus, PCoV-GX/P2V, which was isolated from a Malayan pangolin (Manis javanica). PCoV-GX/P2V could grow in human hepatoma, colorectal adenocarcinoma cells, and human primary nasal epithelial cells. It replicated more efficiently in cells expressing human angiotensin-converting enzyme 2 (hACE2) as SARS-CoV-2 did. After intranasal inoculation to the hACE2-transgenic mice, PCoV-GX/P2V not only replicated in nasal turbinate and lungs, but also caused interstitial pneumonia, characterized by infiltration of mixed inflammatory cells and multifocal alveolar hemorrhage. Existing population immunity established by SARS-CoV-2 infection and vaccination may not protect people from PCoV-GX/P2V infection. These findings further verify the hACE2 utility of PCoV-GX/P2V by in vivo experiments using authentic viruses and highlight the importance for intensive surveillance to prevent possible cross-species transmission.
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Enzima de Conversão de Angiotensina 2 , COVID-19 , Camundongos Transgênicos , Pangolins , SARS-CoV-2 , Animais , Humanos , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/genética , SARS-CoV-2/patogenicidade , SARS-CoV-2/genética , COVID-19/virologia , Pangolins/virologia , Camundongos , Replicação Viral , Pulmão/virologia , Pulmão/patologia , Chlorocebus aethiops , Células VeroRESUMO
OBJECTIVE: To explore the safety and efficacy of frameless stereotactic brain biopsy. METHODS: Diagnostic accuracy was calculated by comparing biopsy diagnosis with definitive pathology in 62 patients who underwent frameless stereotactic brain biopsy between January 2008 and December 2010 in Xiamen University Southeast Hospital. Preoperative characteristics and histological diagnosis were reviewed and then information was analysed to identify factors associated with the biopsy not yielding a diagnosis and complications. RESULTS: Diagnostic yield was 93.5%. No differences were found between pathological diagnosis and frozen pathological diagnosis. The most common lesions were astrocytic lesions, included 16 cases of low-grade glioma and 12 cases of malignant glioma. Remote hemorrhage, metastasis, and lymphoma were following in incidence. Multiple brain lesions were found in 17 cases (27.4%). Eleven cases were frontal lesions (17.7%), 8 were frontotemporal (12.9%), 6 were frontoparietal (9.7%), and 5 each were temporal, parietal, and parietotemporal lesions (8.1%). Postoperative complications occurred in 21.0% of the patients after biopsies, including 10 haemorrhages (16.1%) and 3 temporary neurological deficits (1 epilepsy, 1 headache, and 1 partial hemiparesis). No patient required operation for hematoma evacuation. CONCLUSION: Frameless stereotactic biopsy is an effective and safe technique for histologic diagnosis of brain lesions, particularly for multifocal and frontal lesions.
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Biópsia/métodos , Encéfalo/patologia , Técnicas Estereotáxicas , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas Estereotáxicas/efeitos adversosRESUMO
The PRR11 gene (Proline Rich 11) has been implicated in lung cancer; however, relationship between PRR11 and immune infiltration is not clearly understood. In this study, we used The Cancer Genome Atlas (TCGA) data to analyze the lung adenocarcinoma patients; PRR11 gene expression, clinicopathological findings, enrichment, and immune infiltration were also studied. PRR11 immune response expression assays in lung adenocarcinoma (LUAD) were performed using TIMER, and statistical analysis and visualization were conducted using R software. All data were verified using Gene Expression Profiling Interactive Analysis (GEPIA), and the Human Protein Atlas (HPA). We found that PRR11 was an important prognostic factor in patients with LUAD. PRR11 expression was correlated with tumor stage and progression. Gene Set Enrichment Analysis (GSEA) showed that PRR11 was enriched in the cell cycle regulatory pathways. Immune infiltration analysis revealed that the number of T helper 2 (Th2) cells increased when PRR11 was overexpressed. These results confirm the role of PRR11 as a prognostic marker of lung adenocarcinoma by controlling the cell cycle and influencing the immune system to facilitate lung cancer progression.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Prognóstico , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/genética , Bioensaio , Ciclo CelularRESUMO
There are multiple routes to prepare semi-solid slurries with a globular microstructure for semi-solid forming. The variations in the microstructure of semi-solid slurries prepared using different routes may lead to significant differences in the flow behavior and mechanical properties of rheo-diecasting parts. Therefore, it is crucial to have a comprehensive understanding of the microstructure evolution associated with different slurry preparation routes and their resulting effects. In this study, the gas-induced semi-solid process (GISS) and the swirl enthalpy equilibrium device (SEED) routes were employed to prepare semi-solid Al-Si-Mg slurries for their simplicity and productivity in potential industrial applications. The prepared slurries were then injected into the shoot sleeves of a high-pressure die casting (HPDC) machine to produce tensile test bars. Subsequently, the bars underwent T6 treatment to enhance their mechanical properties. The microstructure, segregation, and mechanical properties of the samples were investigated and compared with those of conventional HPDC. The results indicated that the GISS and SEED can produce semi-solid slurries containing a spherical α-Al primary phase, as opposed to the dendritic structure commonly found in conventional castings. The liquid fraction had a significant effect on the flow behavior, resulting in variations in liquid segregation and mechanical properties. It was observed that a higher solid fraction (>75%) had a suppressing effect on surface liquid segregation. In addition, the tendency for liquid segregation gradually increased along the filling direction due to the special flow behavior of the semi-solid slurry with a low solid fraction. Furthermore, under the same die-casting process parameters, the conventional HPDC samples exhibit higher yield stress (139 ± 3 MPa) compared to SEED-HPDC and GISS-HPDC samples, which may be attributed to the small grain size and the distribution of eutectic phases. After undergoing the T6 treatment, both SEED-HPDC and GISS-HPDC samples showed a significant improvement in yield and tensile strength. These improvements are a result of solution and precipitation strengthening effects as well as the spheroidization of the eutectic Si phase. Moreover, the heat-treated SEED-HPDC samples demonstrate higher ultimate strength (336 ± 5 MPa) and elongation (13.7 ± 0.3%) in comparison to the GISS-HPDC samples (307 ± 4 MPa, 8.8 ± 0.2%) after heat treatment, mainly due to their low porosity density. These findings suggest that both GISS-HPDC and SEED-HPDC processes can be utilized to produce parts with favorable mechanical properties by implementing appropriate heat treatments. However, further investigation is required to control the porosities of GISS-HPDC samples during heat treatment.
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Objective: Hemispherical cerebral swelling or even encephalocele after head trauma is a common complication and has been well elucidated previously. However, few studies have focused on the secondary brain hemorrhage or edema occurring regionally but not hemispherically in the cerebral parenchyma just underneath the surgically evacuated hematoma during or at a very early stage post-surgery. Methods: In order to explore the characteristics, hemodynamic mechanisms, and optimized treatment of a novel peri-operative complication in patients with isolated acute epidural hematoma (EDH), clinical data of 157 patients with acute-isolated EDH who underwent surgical intervention were reviewed retrospectively. Risk factors including demographic characteristics, admission Glasgow Coma Score, preoperative hemorrhagic shock, anatomical location, and morphological parameters of epidural hematoma, as well as the extent and duration of cerebral herniation on physical examination and radiographic evaluation were considered. Results: It suggested that secondary intracerebral hemorrhage or edema was determined in 12 of 157 patients within 6 h after surgical hematoma evacuation. It was featured by remarkable, regional hyperperfusion on the computed tomography (CT) perfusion images and associated with a relatively poor neurological prognosis. In addition to concurrent cerebral herniation, which was found to be a prerequisite for the development of this novel complication, multivariate logistic regression further showed four independent risk factors contributing to this type of secondary hyperperfusion injury: cerebral herniation that lasted longer than 2 h, hematomas that were located in the non-temporal region, hematomas that were thicker than 40 mm, and hematomas occurring in pediatric and elderly patients. Conclusion: Secondary brain hemorrhage or edema occurring within an early perioperative period of hematoma-evacuation craniotomy for acute-isolated EDH is a rarely described hyperperfusion injury. Because it plays an important prognostic influence on patients' neurological recovery, optimized treatment should be given to block or reduce the consequent secondary brain injuries.
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Objective: To investigate the risk factors of intraoperative massive hemorrhage in patients with pernicious placenta previa (PPP) and analyze the value of bilateral internal iliac artery balloon occlusion in Cesarean section for these patients. Methods: The clinical data of 134 patients with PPP admitted to the Second Hospital of Shanxi Medical University from January 2012 to January 2019 were analyzed. A logistic regression analysis was used to analyze the risk factors for intraoperative massive hemorrhage in PPP. The study subjects were divided into the intervention group (38 cases) and the routine group (96 cases) according to whether bilateral internal iliac artery balloon occlusion was conducted during the operation. The differences in some clinical indicators were compared between the two groups. Results: The risk factors for intraoperative massive hemorrhage in PPP were age ≥35 years, gestational age ≥34 weeks, complete placenta previa, and the presence of placenta accreta. The differences in the operation time, postoperative transfer to the intensive care unit, postoperative length of the hospital stay, and neonatal weight and score were not statistically significant between the intervention group and the routine group (P > 0.05 for all). While the intraoperative blood loss and the transfusion volume in the intervention group were lower than in the routine group, the hospitalization cost was higher in the former than in the latter, and the differences were statistically significant (P < 0.05 for all). Moreover, there was no case of hysterectomy in the intervention group, while there were two cases of hysterectomies in the routine group. Conclusion: The risk factors for intraoperative massive hemorrhage in PPP were age ≥35 years, gestational age ≥34 weeks, complete placenta previa, and the presence of placenta accreta. Internal iliac artery balloon occlusion during PPP could reduce intraoperative blood loss and the hysterectomy rate.
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Objective: To investigate the effects of alteplase thrombolysis on coagulation function and nerve function of patients with ischemic stroke. Methods: 76 cases with ischemic stroke receiving thrombolytic therapy in Cangzhou Central Hospital from November 2018 to November 2019 were recruited. They were assigned via the random number table method at a ratio of 1 : 1 to receive alteplase thrombolysis either within 3h after the onset (observation group) or within 3-4.5 h after the onset (control group), followed by aspirin administration after no bleeding in cranial computed tomography (CT). Outcome measures included plasma fibrinogen (FIB), activated partial prothrombin time (APTT), platelet (PLT) levels, the National Institute of Health stroke scale (NIHSS) score, and adverse events. Results: Alteplase thrombolysis within 3 h was associated with better prothrombin time (PT), APTT, FIB, and PLT levels versus thrombolysis within 3-4.5 h (P < 0.05). Thrombolysis within 3 h showed significantly lower NIHSS scores versus within 3-4.5 h (P < 0.05). The two groups showed a similar incidence of adverse events (X 2 = 2.963, P=0.615). Conclusion: Alteplase thrombolysis showed benefits in mitigating the coagulation function and nerve function damage of patients with ischemic stroke, especially within 3 hours after the onset, with a high safety profile.
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An organic-inorganic hybrid silver iodobismuthate characteristic of the infrequent [Ag2BiI6L2] cluster (L = I or I3) and with a unique Ag/Bi molar ratio (2/1), namely, [Zn(bipy)3]2Ag2BiI6(I)1.355(I3)1.645 (bipy = 2,2'-bipyridine; 1), was solvothermally synthesized, and structurally, optically, and theoretically studied. Intriguingly, compound 1 exhibited semiconductor behavior with an optical band gap of 2.33 eV, which endowed it with excellent photoelectric and photocatalytic properties. Electronic structure calculations further revealed that the relative separate conduction band (CB) and valence band (VB) in compound 1 may be responsible for the good optical activity. This study also includes the Hirshfeld surface analyses, thermogravimetric measurements and X-ray photoelectron spectroscopy (XPS) characterization.
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Mucin 13 (MUC13) is a glycoprotein that is expressed on the cell surface and participates in the tumorigenesis of multiple malignancies, including pancreatic cancer, colorectal cancer and renal cancer. However, to the best of our knowledge, the expression levels and function of MUC13 in lung cancer progression have not yet been demonstrated. Therefore, the present study examined the expression pattern and regulatory role of MUC13 in lung cancer tumorigenesis. The results demonstrated that MUC13 was highly expressed in lung cancer tissues and cell lines compared with that in normal tissues and cell lines. Functionally, knockdown of MUC13 inhibited cell proliferation and enhanced the apoptosis of A549 and NCI-H1650 lung cancer cells. Furthermore, silencing of MUC13 suppressed the migration and invasion of lung cancer cells. Additionally, a xenograft tumor model demonstrated that knockdown of MUC13 delayed the development of the lung cancer xenograft and suppressed the expression of proliferation marker Ki-67 in tumor tissues. Mechanistically, MUC13 activated the ERK signaling pathway by enhancing the phosphorylation of ERK, JNK and p38 in lung cancer tissues compared with that in normal tissues. Knockdown of MUC13 inhibited the phosphorylation of ERK/JNK/p38 in A549 and NCI-H1650 cells. Overall, these findings suggested that MUC13 could act as an oncogenic glycoprotein to accelerate the progression of lung cancer via abnormal activation of the ERK/JNK/p38 signaling pathway and might serve as a therapeutic target for lung cancer treatment.
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Developing highly effective HIV latency-reversing agent is an inportmant approach for the treatment of AIDS via the "shock and kill" of latent HIV. In this study, two unreported modified daphnane-type diterpenes (chamaedaphnelide A and epi-chamaedaphnelide A) and one unreported tigliane-type diterpene (chamaedaphnelide B), along with four known daphnane-type diterpenes and one known tigliane-type diterpene were obtained from the leaves of Wikstroemia chamaedaphne. Chamaedaphnelide A and epi-chamaedaphnelide A represents the first A ring cleavage daphnane-type backbone. Chamaedaphnelide A, epi-chamaedaphnelide A, chamaedaphnelide B, and 6α,7α-epoxy-5ß-hydroxy-12-deoxyphorbol-13-decanoate showed HIV latency-reversing activity, especially chamaedaphnelide B and 6α,7α-epoxy-5ß-hydroxy-12-deoxyphorbol-13-decanoate displayed equally potential to positive drugs prostratin with reversing latent HIV on more than 100-fold compared to unstimulated cells. Furthermore, the activation of STAT1 was involved in the HIV latency-reversing activity of these diterpenes, firstly demonstrating that daphnane- and tigliane-type diterpenes can rapidly activate STAT1 activity. Indeed, these results also supported that activating STAT1 activity is a pathway for reversing latent HIV.
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Fármacos Anti-HIV , Diterpenos , HIV , Latência Viral , Fármacos Anti-HIV/farmacologia , Diterpenos/farmacologia , HIV/efeitos dos fármacos , HIV/fisiologia , Infecções por HIV/tratamento farmacológico , Humanos , Folhas de Planta , Fator de Transcrição STAT1/efeitos dos fármacos , Fator de Transcrição STAT1/metabolismo , Latência Viral/efeitos dos fármacos , WikstroemiaRESUMO
The SiS2 rods exhibit a significant anisotropy property applied in a special field such as in the one of all-solid-state lithium-ion batteries and so on. In this work, the orthorhombic SiS2 rods with high chemical/phase purity were prepared by an elemental method, either through a boiling or a steaming process, at 1023-1073 K for 3 h and under the saturated S-vapor pressure (2.57-3.83 MPa) in a closed sealed-tube system. The composition, crystal structure, morphology, and growth mechanism were investigated. Results showed that the growth orientation of SiS2 along the <0 0 1> is intrinsically governed by the crystal structure motif. It could exist in both processes and the latter tends to show in macroscopic morphology. Using the pressure-temperature diagram, structure refinement, pole figures, image analyses, and so forth, factors influencing the purity and growth of SiS2 rods were concluded from the thermodynamics and kinetics viewpoints.
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Species coexistence depends on the comprehensive effects of biological properties and habitat heterogeneity. Based on a large-scale field survey (21°-35° N), we compared the differences on morphological and stoichiometric characteristics between the invasive aquatic species Alternanthera philoxeroides and the native co-occurring species Paspalum paspaloides, and examined the effects of environmental factors on such differences. The results showed that the coverage and importance value (IV) of A. philoxeroides were all significantly greater than P. paspa-loides (34.3% and 104.0%, respectively), whereas the height of P. paspaloides was significantly greater than A. philoxeroides (13.8%). Moreover, the total nitrogen concentration (TN) and N:P of A. philoxeroides were significantly greater than those of P. paspaloides (55.1% and 55.8%, respectively), whereas the total carbon concentration (TC) and C:N of P. paspaloides were significantly greater than those of A. philoxeroides (4.1% and 83.8%, respectively). A. philoxeroides coverage increased with the increases of longitude, and its abundance increased with the increases of water nitrate concentration and longitude, while its IV increased with the increases of water ammonium concentration. However, the coverage, abundance, and IV of P. paspaloides decreased with the increases of ammonium concentration. C:N of A. philoxeroides decreased with the increase of ammonium concentration. Increased mean annual temperature and mean annual precipitation increased C:N but decreased N:P of P. paspa-loides. The C:P of both species decreased with the increases of ammonium concentration and electrical conductivity. N:P of A. philoxeroides was little affected by environment. These results indicated that A. philoxeroides had greater coverage and N absorption capacity than P. paspaloides, and that enriched water nitrogen would aggravate the invasion of A. philoxeroides. Meanwhile, P. paspaloides improved its C-assimilate reserves and chose the growth competition strategy for resisting A. philoxeroides invasion under the superior hydrothermal conditions. Different responses to environmental changes contributed to their coexistence in aquatic ecosystem.