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1.
Mar Genomics ; : 100769, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32229098

RESUMO

The genus Sulfitobacter has been mostly found in marine and hypersaline environments. Members of this genus were observed to be associated with marine microalgae by inducing cell death of algae and degrading of algae-derived dimethylsulfoniopropionate (DMSP). Here we reported the complete genome sequence of strain Sulfitobacter sp. BSw21498 isolated from seawater of Kongsfjorden, an Arctic fjord in Svalbard. The strain contained a circular chromosome of 3,097,372 bp with G+C content of 58.55 mol% and a plasmid of 147,547 bp with G+C content of 56.53 mol%. In particular, a gene for DMSP lyase DddL was found in the genome, rendering Sulfitobacter sp. strain BSw21498 one of the Rhodobacterales bacteria equipped with the potential for DMSP degradation.

2.
Jpn J Radiol ; 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32144554

RESUMO

PURPOSE: The aim of the study was to investigate the diagnostic accuracy of peri-thrombus vascular hyperintensity sign (PVHS) on three-dimensional (3D) black-blood (BB) contrast-enhanced MRI for the detection of intracranial thrombus location and length in acute ischemic stroke (AIS) patients. MATERIALS AND METHODS: Consecutive AIS patients who underwent MRI including 3D BB contrast-enhanced MRI sequence within 8 h of clinical onset were prospectively evaluated. Two readers independently reviewed the 3D BB contrast-enhanced MRI data to assess the presence and location of PVHS. Findings were compared with those of contrast-enhanced MR angiography (CE-MRA) as the reference standard. RESULTS: The PVHS was identified in 49% (63/129) of AIS patients with good agreement. The PVHS had 100% specificity, 88% negative predictive value, 89% sensitivity, and 100% positive predictive value for detection of acute arterial occlusions. Eight patients showed discordant thrombus locations between 3D BB contrast-enhanced MRI and CE-MRA. Median thrombus length in patients with complete occlusion was 9.61 mm. CONCLUSION: The PVHS on 3D BB contrast-enhanced MRI is a highly specific tool for evaluating the location and length of a thrombus in AIS patients.

3.
CNS Neurosci Ther ; 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32196977

RESUMO

INTRODUCTION: Essential tremor (ET) is one of the most prevalent movement disorders. The genetic etiology of ET has not been well defined although a significant proportion (≥50%) are familial cases. Linkage analysis and genome-wide association studies (GWASs) have identified several risk variants. In recent years, whole-exome sequencing of ET has revealed several specific causal variants in FUS (p.Q290X), HTRA2 (p.G399S), and TENM4 (c.4324 G>A, c.4100C>A, and c.3412G>A) genes. OBJECTIVE: To investigate the genetic contribution of these three genes to ET, the protein-coding sequences of FUS, HTRA2, and TENM4 were analyzed in a total of 238 ET patients and 272 controls from eastern China using direct Sanger sequencing. RESULTS: We identified two synonymous coding single nucleotide polymorphisms (SNPs), rs741810 and rs1052352 in FUS, and three previously reported synonymous SNPs, rs11237621, rs689369, and rs2277277 in TENM4. No nonsynonymous exonic variants were identified in these subjects. We found that the frequency of the rs1052352C allele was significantly higher (P = .001) in the ET group than in the control group. CONCLUSION: Overall, our findings suggest that rs1052352 of FUS might contribute to ET risk in Chinese population.

4.
J Immunol Res ; 2020: 9146042, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32211444

RESUMO

The neutrophil-lymphocyte ratio (NLR) and the platelet-lymphocyte ratio (PLR) are markers of systemic inflammation. However, there is little evidence of the value of inflammation in the early diagnosis of gastric cancer (GC). A total of 2,606 patients diagnosed with GC in the past three years and 3,219 healthy controls over the same period were included in this study. Peripheral blood samples were obtained to analyze the NLR, PLR, carcinoembryonic antigen (CEA), and carbohydrate antigen 19-9 (CA19-9). The optimal cutoff levels for the NLR and PLR were defined by receiver operating characteristic (ROC) curve analysis (NLR = 2.258, PLR = 147.368). The value of different biomarkers for diagnosing GC was compared by the area under the curve (AUC). The NLR and PLR showed diagnostic sensitivity in GC (AUC = 0.715, AUC = 0.707). Using the Bonferroni correction, the NLR and PLR were superior to CEA and CA19-9 in the diagnosis of GC (P < 0.0001). The systemic inflammatory markers were significantly higher in the early stage of GC than tumor markers. After grouping patients and healthy controls by gender, we found that the diagnostic significance of combined NLR and PLR for GC was greater in male patients than in female patients (P < 0.0001). The diagnostic value of the NLR and PLR in GC is higher than that of the traditional tumor markers CEA and CA19-9. Systemic markers of inflammation are more valuable in male than female patients.

5.
J Neurol ; 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32008072

RESUMO

BACKGROUND AND PURPOSE: This study aimed at developing a radiomics signature (R score) as prognostic biomarkers based on penumbra quantification and to validate the radiomics nomogram to predict the clinical outcomes for thrombolysis for acute ischemic stroke (AIS) patients. METHODS: In total, 168 patients collected from seven centers were retrospectively included. A score of mismatch was defined as MIS. Based on a short-term clinical label, 456 radiomics features were evaluated with feature selection methods. R score was constructed with the selected features. To compare the predictive capabilities of the clinical factors, MIS, and R score, three nomograms were developed and evaluated, according to the short-term clinical assessment on day 7. Finally, the radiomics nomogram was validated by predicting the 3-month clinical outcomes of AIS patients, in an external cohort. RESULTS: R scores were found to be significantly higher in patients with favorable clinical outcomes in both training and validation datasets. The predictive value of the radiomics nomogram estimating favorable clinical outcomes was modest, with a concordance index (C-index) of 0.695 [95% confidence interval (CI) 0.667-0.723) in an external validation dataset. In addition, the area under curve (AUC) of the radiomics nomogram predicting favorable clinical outcome reached 0.886 (95% CI 0.809-0.963) on day 7 and 0.777 (95% CI 0.666-0.888) at 3 months. CONCLUSIONS: The radiomics signature is an independent biomarker for estimating the clinical outcomes in AIS patients. By improving the individualized prediction of the clinical outcome for AIS patients 3 months after onset, the radiomics nomogram adds more value to the current clinical decision-making process.

6.
BMC Pulm Med ; 20(1): 40, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054470

RESUMO

BACKGROUND: CHCHD2 was identified a novel cell migration-promoting gene, which could promote cell migration and altered cell adhesion when ectopically overexpressed in NIH3T3 fibroblasts, and it was identified as a protein necessary for OxPhos function as well. However, the clinic relevance of CHCHD2 expression in NSCLC remains unclear. Here we assumed that CHCHD2 expression would accompanies the expression of HIF-1α to response hypoxia in the occurrence of NSCLC. METHODS: In order to verify this hypothesis, correlations among the expression levels of CHCHD2 and HIF-1α were detected and analyzed in 209 pair cases of NSCLC. The expression and location of these molecules were assessed using Immunohistochemistry, immunohistofluorescence, qRT-PCR and western blotting. The differences and correlations of the expression of these two molecules with clinical pathological characteristics in NSCLC were statistically analyzed using Wilcoxon (W) text, Mann-Whitney U, Kruskal-Wallis H and cross-table tests. Kaplan-Meier survival analysis and Cox proportional hazards models were used to estimate the effect of the expression of CHCHD2 and HIF-1α on the patients' survival. RESULTS: Data showed that CHCHD2 and HIF-1α expression were higher in NSCLC than in normal tissues (all P = 0.000). CHCHD2 expression was significantly related with smoking, tumor size, differentiation degree, TNM Stage, lymph metastasis (all P<0.05). The HIF-1α expression was significantly associated with smoking, tumor category, differentiation degree, TNM Stage, Lymph metastasis (all P<0.05). There was a marked correlation of CHCHD2 and HIF-1α expression with histological type, differentiation and lymph metastasis of NSCLC (all P<0.05, rs>0.3). Immunohistofluorescence showed that there were co-localization phenomenon in cytoplasm and nucleus between CHCHD2 and HIF-1α expression. NSCLC patients with higher CHCHD2 and HIF-1α expression had a significantly worse prognosis than those with lower CHCHD2 and HIF-1α expression (all P = 0.0001; log-rank test). The multivariate analysis indicated that CHCHD2 expression was an independent prognostic factor in NSCLC (hazard ratio [HR], 0.492, P = 0.001). CONCLUSION: Our results indicate that over-expression of CHCHD2 would promote the expression of HIF-1α to adapt the hypoxia microenviroment in NSCLC and CHCHD2 could serves as a prognostic biomarker in NSCLC.

7.
Cancer Med ; 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32096331

RESUMO

BACKGROUND: Emerging evidence indicates that the tumor microenvironment (TME) influences tumor progression through the various cells it contains. Tumor-associated neutrophils (TANs) and cancer-associated fibroblasts (CAFs) are prominent constituents of diverse malignant solid tumors and are crucial in the TME and cancer evolution. However, the relationships and combined prognostic value of these two cell types are not known in gastric adenocarcinoma (GAC). MATERIALS AND METHODS: In total, 215 GAC patients who underwent curative surgery were enrolled. TANs were assessed by immunohistochemical staining for CD66b, and CAFs were evaluated by immunohistochemical staining for α-smooth muscle actin (α-SMA). RESULTS: The percentages of patients with high-density TANs and CAFs in GAC tissue were 47.9% (103/215) and 43.3% (93/215), respectively. The densities of TANs and CAFs in GAC tissue samples were markedly elevated and independently correlated with GAC clinical outcomes. A strong correlation (R = .348, P < .001) was detected between TANs and CAFs in GAC. The combination of TANs and CAFs produced a more exact outcome than either factor alone. Patients with an α-SMAlow CD66bhigh (hazard ratio [HR] = 1.791; 95% CI: 1.062-3.021; P = .029), α-SMAhigh CD66blow (HR = 2.402; 95% CI: 1.379-4.183; P = .002), or α-SMAhigh CD66bhigh (HR = 3.599; 95% CI: 2.330-5.560; P < .001) phenotype were gradually correlated with poorer disease-free survival than the subset of patients with an α-SMAlow CD66blow phenotype. The same results were observed for disease-specific survival in the subgroups. Noticeably, in stage II-III patients with the α-SMAlow CD66blow phenotype, an advantage was obtained with postoperative chemotherapeutics, and the risk of a poor prognosis was reduced compared with stage II-III patients with the α-SMAlow CD66bhigh , α-SMAhigh CD66blow or α-SMAhigh CD66bhigh phenotype (HR: 0.260, 95% CI: 0.124-0.542, P < .001 for disease-free survival; and HR: 0.258, 95% CI: 124-0.538, P < .001 for disease-specific survival). CONCLUSION: Overall, we concluded that the combination of CD66b+ TANs and α-SMA+ CAFs could be used as an independent factor for patient outcomes and to identify GAC patients who might benefit from the administration of postoperative chemotherapeutics.

8.
Cells ; 9(1)2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31968566

RESUMO

Innate immunity represents the human immune system's first line of defense against a pathogenic intruder and is initiated by the recognition of conserved molecular structures known as pathogen-associated molecular patterns (PAMPs) by specialized cellular sensors, called pattern recognition receptors (PRRs). Human immunodeficiency virus type 1 (HIV-1) is a unique human RNA virus that causes acquired immunodeficiency syndrome (AIDS) in infected individuals. During the replication cycle, HIV-1 undergoes reverse transcription of its RNA genome and integrates the resulting DNA into the human genome. Subsequently, transcription of the integrated provirus results in production of new virions and spreading infection of the virus. Throughout the viral replication cycle, numerous nucleic acid derived PAMPs can be recognized by a diverse set of innate immune sensors in infected cells. However, HIV-1 has evolved efficient strategies to evade or counteract this immune surveillance and the downstream responses. Understanding the molecular underpinnings of the concerted actions of the innate immune system, as well as the corresponding viral evasion mechanisms during infection, is critical to understanding HIV-1 transmission and pathogenesis, and may provide important guidance for the design of appropriate adjuvant and vaccine strategies. Here, we summarize current knowledge of the molecular basis for sensing HIV-1 in human cells, including CD4+ T cells, dendritic cells, and macrophages. Furthermore, we discuss the underlying mechanisms by which innate sensing is regulated, and describe the strategies developed by HIV-1 to evade sensing and immune responses.

9.
ChemSusChem ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31898849

RESUMO

Nickel oxide (NiO) materials with excellent stability and favorable energy bands are desirable candidates for hole-selective contact (HSC) of inverted perovskite solar cell (PSC). However, studies that focus on addressing interfacial issues, which are induced by the poor NiO/perovskite contact or other defects, are scarce. In this study, a facile one-step hydrothermal strategy is demonstrated for the development of a 3 D NiO nanowall (NW) film as a promising HSC. The new NiO NWs HSC exhibits a robust and homogenous mesoporous network structure, which improved the NiO/perovskite interface contact, passivated the interfacial defect and improved the quality of the perovskite film. The optimized interface features enabled a power conversion efficiency (PCE) approaching 18 %. A diethanolamine (DEA) interlayer was introduced to further passivate the intrinsic defect of the NiO surface, resulting in better charge transfer with suppressed recombination loss. As a result, the champion PCE of the NiO NWs/DEA-based device was increased to 19.16 % with a high open-circuit voltage (≈1.11 V) and fill factor (>80 %), which is prominent in methylammonium lead iodide-based inverted PSCs. Furthermore, the device exhibited better stability and lower hysteresis behavior than a conventional solution-based NiO nanocrystal device.

10.
Nat Prod Res ; : 1-9, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31951465

RESUMO

Two new alkaloids named Melongenamides H-I (1-2), together with twenty-one known compounds (3-23), were isolated from the 70% ethanol extract of the sepals of Solanum melongena L. The structures of all isolated compounds were determined by 1D and 2D NMR spectra and by comparing their spectroscopic and physical data with values from the published literatures. All the isolated compounds were evaluated the cytotoxicity against three human canner lines (Hela, Ishikawa and MGC-803) by CCK8 assay.

11.
J Virol ; 94(2)2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31666373

RESUMO

The low-pathogenic H7N9 influenza viruses that emerged in 2013 acquired an insertion of four amino acids in their hemagglutinin cleavage site and thereby became highly pathogenic to chickens in 2017. Previous studies indicated that these highly pathogenic H7N9 viruses are virulent in chickens but have distinct pathotypes in mice. A/chicken/Guangdong/SD098/2017 (CK/SD098) is avirulent, with a 50% mouse lethal dose (MLD50) of >7.5 log10 50% egg infectious dose (EID50), whereas A/chicken/Hunan/S1220/2017 (CK/S1220) is virulent in mice, with an MLD50 of 3.2 log10 EID50 In this study, we explored the genetic determinants that contribute to the difference in virulence between these two H7N9 viruses by generating a series of reassortants and mutants in the CK/S1220 virus background and testing their virulence in mice. We found that the reassortant CK/1220-SD098-NP, carrying the nucleoprotein (NP) of CK/SD098, was avirulent in mice, with an MLD50 of >107.5 EID50 The NPs of these two viruses differ by two amino acids, at positions 286 and 437. We further demonstrated that the amino acid mutations A286V and T437M of NP independently slowed the process of NP import to and export from the nucleus and thus jointly impaired the viral life cycle and attenuated the virulence of these H7N9 viruses in mice. Our study identified new virulence determinants in NP and provided novel targets for the development of live attenuated vaccines and antiviral drugs against influenza viruses.IMPORTANCE The H7N9 influenza viruses that emerged in China in 2013 have caused over 1,500 human infections, with a mortality rate of nearly 40%. The viruses were initially low pathogenic but became highly pathogenic in chickens at the beginning of 2017 and caused severe disease outbreaks in poultry. Several studies suggested that the highly pathogenic H7N9 viruses have increased virulence in mammals; however, the genetic basis of the virulence of H7N9 viruses in mammals is not fully understood. Here, we found that two amino acids, 286A and 437T, in NP are prerequisites for the virulence of H7N9 viruses in mice and the mutations A286V and T437M collectively eliminate the virulence of H7N9 viruses in mice. Our study further demonstrated that the virulence of influenza viruses is a polygenic trait, and the newly identified virulence-related residues in NP may provide new targets for attenuated influenza vaccine and antiviral drug development.

12.
J Sci Food Agric ; 100(3): 1064-1071, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31713870

RESUMO

BACKGROUND: Glucosinolates (GSLs) are secondary metabolites, mainly existing in Brassica vegetables. Their breakdown products have health benefits and contribute to the distinctive taste of these vegetables. Because of their high value, there is a lot of interest in developing breeding strategies to increase the content of beneficial GSLs in Brassica species. GSLs are synthesized from certain amino acids and their biological roles depend largely on the structure of their side chains. Flavin-containing monooxygenase (FMOGS-OX ) genes are involved in the synthesis of these side chains. To better understand GSL biosynthesis, we sequenced the transcriptomes of turnip (Brassica rapa var. rapa) tubers at four developmental stages (S1-S4) and determined their GSL content. RESULTS: The total GSL content was high at the early stage (S1) of tuber development and increased up to S3, then decreased at S4. We detected 61 differentially expressed genes, including five FMOGS-OX genes, that were related for GSL biosynthesis among the four developmental stages. Most of these genes were highly expressed at stages S1 to S3, but their expression was much lower at S4. We estimated the effect of the five FMOGS-OX genes on GSL content by overexpressing them in turnip hairy roots and found that the amount of aliphatic GSLs increased significantly in the transgenic plants. CONCLUSION: The transcriptome data and characterization of genes involved in GSL biosynthesis, particularly the FMOGS-OX genes, will be valuable for improving the yield of beneficial GSLs in turnip and other Brassica crops. © 2019 Society of Chemical Industry.


Assuntos
Brassica rapa/enzimologia , Brassica rapa/crescimento & desenvolvimento , Glucosinolatos/biossíntese , Oxigenases de Função Mista/metabolismo , Proteínas de Plantas/metabolismo , Vias Biossintéticas , Brassica rapa/genética , Brassica rapa/metabolismo , Dinitrocresóis/metabolismo , Regulação da Expressão Gênica de Plantas , Oxigenases de Função Mista/genética , Proteínas de Plantas/genética , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Transcriptoma
13.
Nat Prod Res ; 34(3): 359-368, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30600708

RESUMO

Phytochemical investigation of the roots of Solanum melongena L. resulted in the isolation of ten terpenes and sixteen lignans, including a new triterpene saponin, officinoterpenoside E (1) and twenty-five known compounds (2-26). All compounds were firstly isolated from S. melongena except 2, 13, 21, 22. The structures of these compounds were determined by 1 D and 2 D NMR spectra referring to the literatures, together with high-resolution mass spectrometric analysis. All compounds were evaluated for the cytotoxicity against three cancer cell lines (HepG2, Hela, and MCF-7) in vitro. The results showed that compounds 1, 6, 20, 25 and 26 exhibited moderate cytotoxicity against HepG2, Hela and MCF-7 cells with IC50 values in the range of 16.8 ± 1.7 to 29.1 ± 1.9 µM. Therefore, these terpenoids and lignans may have potential biological activity, and also seemed to be of great chemotaxonomic value for S. melongena.

14.
Opt Express ; 27(21): 29567-29580, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684216

RESUMO

Nonlinear impairments induced by the opto-electronic components are one of the fundamental performance-limiting factors in high-speed optical short-reach communications, significantly hindering capacity improvement. This paper proposes to employ a kernel mapping function to map the signals in a Hilbert space to its inner product in a reproducing kernel Hilbert space, which has been successfully demonstrated to mitigate nonlinear impairments in optical short-reach communication systems. The operation principle is derived. An intensity modulation/direct detection system with 1.5-µm vertical cavity surface emitting laser and 10-km 7-core fiber achieving 540.68-Gbps (net-rate 505.31-Gbps) has been carried out. The experimental results reveal that the kernel mapping based schemes are able to realize comparable transmission performance as the Volterra filtering scheme even with a high order.

15.
ACS Appl Mater Interfaces ; 11(47): 44308-44314, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31687805

RESUMO

Inverted perovskite solar cells (PSCs) demonstrate attractive features in developing an air-stable photovoltaic device, by employing inorganic hole transport layers (HTLs). However, their power conversion efficiencies are still inferior to that of mesoporous n-i-p devices, mainly attributed to the undesirable hole extraction and interfacial recombination loss. Here, we design a novel one-dimensional NiO nanotube (NT) nanoforest as efficient mesoporous HTLs. Such a NiO NT mesoporous structure provides a highly conductive pathway for rapid hole extraction and depresses interfacial recombination loss. Furthermore, excellent light capturing could be achieved by optimizing the length and branch growth of the NiO NT nanoforest, which mimics the evolution of the natural forest. Therefore, this inverted mesoporous PSCs yield an optimal efficiency of 18.77%, which is still prominent in state-of-the-art NiO-based devices. Alternatively, the mesoporous device exhibits greatly improved long-term stability. This work provides a new design perspective for developing high-performance inverted PSCs.

16.
Medicine (Baltimore) ; 98(44): e17526, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689754

RESUMO

RATIONALE: Hereditary hemochromatosis (HH) is a frequent autosomal recessive disease. The pathogenesis of disease is excessive intestinal absorption of dietary iron, resulting in pathologically high iron storage in tissues and organs. As a systemic disease, it has several manifestations including cirrhosis, diabetes mellitus, cardiomyopathy, joint disease. However, a proportion of patients are asymptomatic. PATIENT CONCERNS: A 34-year-old man who had abnormal liver function for 9 months without specific symptoms. He underwent various tests, including liver biopsy and genetic testing, which eventually ruled out common liver diseases and identified iron metabolic abnormalities. In addition, we confirmed the pathogenic genes by sequencing the genes of him and his families. DIAGNOSIS: Combined with the symptoms, auxiliary examinations and sequencing results, the patient was diagnosed as HH. INTERVENTIONS: The patient was given a low iron diet and phlebotomy therapy interval 2 weeks until the ferritin is <100 mg/L. OUTCOMES: The patient' condition is stable during the follow-up period. LESSONS: When clinicians are confronted with unexplained liver dysfunction, the possibility of the HH should be considered. Liver biopsy and gene sequencing are helpful in diagnosis. Phlebotomy treatment is the most economical and practical treatment for HH at present, but it should vary from person to person.


Assuntos
Proteínas de Transporte de Cátions/genética , Hemocromatose/genética , Adulto , Hemocromatose/diagnóstico , Hemocromatose/terapia , Humanos , Masculino , Flebotomia/métodos
17.
J Nat Prod ; 82(12): 3242-3248, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31742403

RESUMO

Melongenaterpenes A-L (1-12), 12 new sesquiterpenoids with rare spiro[4.5]decane skeletons, were isolated from the roots of Solanum melongena. Their 2D structures and relative configurations were determined based on NMR and HRESIMS data. The absolute configuration of melongenaterpene A (1) was defined by X-ray crystallographic analysis. The absolute configurations of the remaining compounds were determined by comparison of their NMR data with 1 and consideration of the biosynthetic pathway. This is the first report of the crystal structure of a vetispirane-type sesquiterpenoid. None of the compounds exhibited cytotoxic activity against the three human cancer cell lines HepG2, HeLa, and MCF-7.

18.
Sci Rep ; 9(1): 17477, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767953

RESUMO

The effect of ultra-narrowband light absorption enhancement is presented by using metamaterials with symmetry-broken square silicon patches (SSPs). The symmetry of the SSP can be broken by introducing a narrow slit deviating from its center. By breaking the symmetry of the SSPs, slit resonance mode with standing wave patterns can be excited, and the locations of the absorption peaks can be well estimated by using the Fabry-Pérot (F-P) cavity model. Although there is no excitation of surface plasmon resonance, ultra-narrowband light absorption can be achieved by minimizing the reflectance through perfect impedance matching and simultaneously eliminating the transmittance by the metallic substrate. Good ultra-narrowband absorption features can be maintained as the parameters of the buffer layer and the SSPs are altered. When this type of symmetry-broken SSPs-based metamaterial is used in refractive-index sensors, it shows excellent sensing properties due to its stable ultra-narrowband absorption enhancement.

19.
Front Cell Dev Biol ; 7: 267, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781559

RESUMO

Several studies have investigated strategies to improve the clinical efficacy of radiotherapy (RT) against hepatocellular carcinoma (HCC), yet the prognosis remains poor. Human adipose tissue-derived mesenchymal stem cells (AT-MSCs), easily accessible and abundant in quantity, have represented as an attractive therapeutic tool for the stem cell-based treatment for cancer diseases. Through direct co-culture and indirect separate culture experiments, we showed that AT-MSCs could enhance inhibitory effect of RT on reducing HCC cell growth, migration and invasion in both in vitro and in vivo experiments. RNA-sequencing analysis revealed a noticeable interferon-induced transmembrane 1 (IFITM1)-induced tumor gene signature. Gain and loss of mechanistic studies indicated that mechanism was attributed to downregulated expression of signal transducer and activator of transcription 3 (STAT3) and matrix metallopeptidases (MMPs) and upregulated expression of P53 and caspases. Collectively, our findings suggest that AT-MSCs might enhance the therapeutic effects of RT on HCC, providing a rationale for AT-MSCs and RT combination therapy as a new remedy for HCC.

20.
J Neuroinflammation ; 16(1): 206, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699098

RESUMO

BACKGROUND: Oligodendrocytes (OLs) death after spinal cord injury (SCI) contributes to demyelination, even leading to a permanent neurological deficit. Besides apoptosis, our previous study demonstrated that OLs underwent receptor-interacting serine-threonine kinase 3(RIP3)/mixed lineage kinase domain-like protein (MLKL)-mediated necroptosis. Considering that necroptosis is always accompanied with pro-inflammatory response and quercetin has long been used as anti-inflammatory agent, in the present study we investigated whether quercetin could inhibit necroptosis of OLs and suppress the M1 macrophages/microglia-mediated immune response after SCI as well as the possible mechanism. METHODS: In this study, we applied quercetin, an important flavonoid component of various herbs, to treat rats with SCI and rats injected with saline were employed as the control group. Locomotor functional recovery was evaluated using Basso-Beattie-Bresnahan (BBB) scoring and rump-height Index (RHI) assay. In vivo, the necroptosis, apoptosis, and regeneration of OLs were detected by immunohistochemistry, 5'-bromo-2'-deoxyuridine (BrdU) incorporation. The loss of myelin and axons after SCI were evaluated by Luxol fast blue (LFB) staining, immunohistochemistry, and electron microscopic study. The polarization of macrophages/microglia after SCI and the underlying mechanisms were detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemistry. In vitro, the ATP and reactive oxygen species (ROS) level examination, propidium iodide (PI) labeling, and Western blotting were used to analyze the necroptosis of cultured OLs, while the signaling pathways-mediated polarization of cultured macrophages/microglia was detected by qRT-PCR and Western blotting. RESULTS: We demonstrated that quercetin treatment improved functional recovery in rats after SCI. We then found that quercetin significantly reduced necroptosis of OLs after SCI without influencing apoptosis and regeneration of OLs. Meanwhile, myelin loss and axon loss were also significantly reduced in quercetin-treated rats, as compared to SCI + saline control. Further, we revealed that quercetin could suppress macrophages/microglia polarized to M1 phenotype through inhibition of STAT1 and NF-κB pathway in vivo and in vitro, which contributes to the decreased necroptosis of OLs. CONCLUSIONS: Quercetin treatment alleviated necroptosis of OLs partially by inhibiting M1 macrophages/microglia polarization after SCI. Our findings suggest that necroptosis of OLs may be a potential therapeutic target for clinical SCI.

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