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1.
J Med Virol ; 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31429946

RESUMO

Hepatitis B virus (HBV) DNA is vulnerable to editing by human apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like (APOBEC) cytidine deaminases. However, the distribution of APOBEC-induced mutations on HBV DNA is not well characterized. To this end, we obtained the HBV DNA sequence of HBV-infected individuals with and without hepatocellular carcinoma (HCC and non-HCC groups, respectively) from NCBI database and calculated the rapo values of APOBEC-induced TpCpW→TpKpW mutation prevalence in HBV DNA. The results showed that the APOBEC-induced mutations were mainly distributed in the minus strand of non-HCC-derived HBV DNA (rapo = 2.04), while the mutation on the plus-strand was weaker (rapo = 0.99). There were high APOBEC-induced mutation regions in the minus strand of HBV DNA 1 to 1000 nucleotides (nts) region and in the plus-strand of HBV DNA 1000 to 1500 nts region; the mutations in the 1 to 1000 nts region were mainly TpCpW→TpTpW mutation types (total T/G: 111/18) and a number of these were missense mutations (missense/synonymous: 35/94 in P gene, 17/15 in S gene, and 5/10 in X gene). The difference between minus to plus-strand rapo of HCC-derived HBV DNA (1.96) was greater than that of the non-HCC group (1.05). The minus-strand rapo of HCC-derived HBV DNA regions 1000 to1500nts and 1500 to 2000 nts (rapo = 4.2 and 4.2) was also higher than that of the same regions of non-HCC-derived HBV DNA (rapo = 1.2 and 1.1). Finally, the ratio of minus to plus-strand rapo was used to distinguish HCC-derived HBV DNA from non-HCC-derived HBV DNA. This study unraveled the distribution characteristics of APOBEC-induced mutations on double strands of HBV DNA from HCC and non-HCC samples. Our findings would help understand the mechanism of APOBECs on HBV DNA and may provide important insights for the screening of HCC.

2.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2490-2500, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418252

RESUMO

Microalgae has the advantages of high growth rates, high cellular lipid productivity and capability to bio-sequester carbon dioxide, and thus being widely studied as a new generation of biomass energy. The sustained investment in freshwater resources and nutrients during its growth period, however, is a major obstacle to large-scale cultivation. Combining a microalgae culture system with wastewater treatment is an economically viable wastewater resource utilization strategy. Based on the utilization mechanism of nutrients such as nitrogen and phosphorus during the growth of microalgae, we reviewed the application of microalgae in the biological wastewater treatment. The removal/inhibition ability of organic and inorganic compounds, heavy metals and pathogens were analyzed. The effects of environmental factors including the initial nutrient concentration, light, temperature, pH, salinity and gas exchange on the growth and metabolism of microalgae were investigated. In addition, combined with the problems faced by the large-scale application of microalgae, the application prospect and development direction of microalgae wastewater treatment were prospected, with the aim to provide references for the construction and management of water ecosystems.


Assuntos
Biodegradação Ambiental , Microalgas , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Biomassa , Nitrogênio , Fósforo
3.
Eur Radiol ; 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31396730

RESUMO

OBJECTIVES: To determine the integrative value of contrast-enhanced computed tomography (CECT), transcriptomics data and clinicopathological data for predicting the survival of bladder urothelial carcinoma (BLCA) patients. METHODS: RNA sequencing data, radiomics features and clinical parameters of 62 BLCA patients were included in the study. Then, prognostic signatures based on radiomics features and gene expression profile were constructed by using least absolute shrinkage and selection operator (LASSO) Cox analysis. A multi-omics nomogram was developed by integrating radiomics, transcriptomics and clinicopathological data. More importantly, radiomics risk score-related genes were identified via weighted correlation network analysis and submitted to functional enrichment analysis. RESULTS: The radiomics and transcriptomics signatures significantly stratified BLCA patients into high- and low-risk groups in terms of the progression-free interval (PFI). The two risk models remained independent prognostic factors in multivariate analyses after adjusting for clinical parameters. A nomogram was developed and showed an excellent predictive ability for the PFI in BLCA patients. Functional enrichment analysis suggested that the radiomics signature we developed could reflect the angiogenesis status of BLCA patients. CONCLUSIONS: The integrative nomogram incorporated CECT radiomics, transcriptomics and clinical features improved the PFI prediction in BLCA patients and is a feasible and practical reference for oncological precision medicine. KEY POINTS: • Our radiomics and transcriptomics models are proved robust for survival prediction in bladder urothelial carcinoma patients. • A multi-omics nomogram model which integrates radiomics, transcriptomics and clinical features for prediction of progression-free interval in bladder urothelial carcinoma is established. • Molecular functional enrichment analysis is used to reveal the potential molecular function of radiomics signature.

4.
Mol Cancer Res ; 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31292202

RESUMO

Mutations in isocitrate dehydrogenases 1 and 2 (IDH) occur in the majority of World Health Organization grade II and III gliomas. IDH1/2 active site mutations confer a neomorphic enzyme activity producing the oncometabolite D-2-hydroxyglutarate (D-2HG), which generates the glioma CpG island methylation phenotype (G-CIMP). While IDH1/2 mutations and G-CIMP are commonly retained during tumor recurrence, recent work has uncovered losses of the IDH1 mutation in a subset of secondary glioblastomas. Cooccurrence of the loss of the mutant allele with extensive methylation changes suggests a possible link between the two phenomena. Here, we utilize patient-derived IDH1R132H/WT glioma cell lines and CRISPR-Cas9-mediated gene knockout to model the genetic loss of IDH1 R132H, and characterize the effects of this deletion on DNA methylation. After D-2HG production has been abolished by deletions within the IDH1 alleles, these models show persistent DNA hypermethylation at seven CpG sites previously used to define G-CIMP-positivity in patient tumor samples. Despite these defining G-CIMP sites showing persistent hypermethylation, we observed a genome-wide pattern of DNA demethylation, enriched for CpG sites located within open sea regions of the genome, as well as in CpG-island shores of transcription start sites, after loss of D-2HG production. These results suggest that inhibition of D-2HG from genetic deletion of IDH alleles is not sufficient to reverse hypermethylation of all G-CIMP-defining CpG sites, but does result in more demethylation globally and may contribute to the formation of a G-CIMP-low-like phenotype.Implications: These findings show that loss of the IDH1 mutation in malignant glioma cells leads to a pattern of DNA methylation alterations, and shows plausibility of IDH1 mutation loss being causally related to the gain of a G-CIMP-low-like phenotype.

5.
Chemosphere ; 236: 124281, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31310980

RESUMO

Microcystinase (MlrA) catalyzes the first and most important biodegradation step of hepatotoxic microcystin-LR (MC-LR) produced and released from cyanobacterial cells, and the underlying catalytic mechanism is not completely understood yet. MlrA was postulated previously to be a metalloprotease with an active site of H260AIH263NE265, a variant of the common metal-binding motif of HEXXH. Through comparison with representative modes in HEXXH-containing metalloproteases, molecular dynamics simulation, homology modeling, and docking, the active sites of MlrA involved in the MC-LR biodegradation by Sphingomonas sp. USTB-05 were predicted. Site-directed mutants of MlrA were constructed for verification then. The results show that MlrA is likely not a metalloprotease, but a glutamate protease belonging to type II CAAX prenyl endopeptidases. Combined with the biodegradation of MC-LR by MlrA and its mutants, a complete enzymatic mechanism for MC-LR biodegradation by MlrA is proposed: Glu172 and His205 activate a water molecule facilitating a nucleophilic attack on the Adda-Arg peptide bond of MC-LR; Trp176 and Trp201 contact the carboxylate side chain of Glu172and, by raising its pKa potentially, accelerate the reaction rates; His260 and Asn264 (located in the previous postulated active center of H260AIH263NE265) function as an oxyanion hole to stabilize the transition states. This study reveals the enzymatic mechanism of MlrA for catalyzing MC-LR in both the representative modes and the experiments of site-directed mutagenesis.

6.
Ther Drug Monit ; 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31268965

RESUMO

BACKGROUND: Tacrolimus has been widely accepted as the backbone of acute graft-versus-host disease (aGVHD) prophylaxis in allogeneic hematopoietic stem cell transplantation (alloHSCT). The present work evaluated whether tacrolimus concentrations early post-transplant correlate with the incidence of aGVHD in Chinese alloHSCT recipients. METHODS: One hundred and four Chinese alloHSCT recipients were included in this retrospective study. All patients received standard prophylaxis with tacrolimus and short-term methotrexate. Blood samples were taken at steady state for those on i.v. tacrolimus (Cv) or predose (C0) and 2 hours after the last oral dose (C2). RESULTS: In the first 8 weeks after alloHSCT, significant variability in Cv, C0 and C2 of Chinese patients was observed. It was found that higher tacrolimus C0 and C2 values tended to be associated with a reduced risk of aGVHD, although this was a non-significant trend due to the small sample size involved. Receiver operating characteristic (ROC) curve analysis indicated that Cv levels of ≥ 16.52 ng/mL, C0 levels of ≥ 5.56 ng/mL and C2 levels of ≥ 7.83 ng/mL minimized the incidence of treatment failure during weeks 3-4 with intravenous administration and weeks 5-6 with oral administration. There was no statistically significant association of patient liver and kidney function with the blood concentration of tacrolimus in the desired range of 5 to 20 ng/mL. CONCLUSIONS: Tacrolimus therapeutic drug monitoring improved treatment outcomes of Chinese alloHSCT recipients. Cv measurements during weeks 3 to 4 and C0 or C2 measurements during weeks 5 to 6 better predicted aGVHD (I-IV) than the concentrations measured at other time points during the first 6 weeks after alloHSCT.

7.
Molecules ; 24(15)2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31357453

RESUMO

Polymyxins are considered to be the last-line antibiotics that are used to treat infections caused by multidrug-resistant (MDR) gram-negative bacteria; however, the plasmid-mediated transferable colistin resistance gene (mcr-1) has rendered polymyxins ineffective. Therefore, the protein encoded by mcr-1, MCR-1, could be a target for structure-based design of inhibitors to tackle polymyxins resistance. Here, we identified racemic compound 3 as a potential MCR-1 inhibitor by virtual screening, and 26 compound 3 derivatives were synthesized and evaluated in vitro. In the cell-based assay, compound 6g, 6h, 6i, 6n, 6p, 6q, and 6r displayed more potent activity than compound 3. Notably, 25 µΜ of compound 6p or 6q combined with 2 µg·mL-1 colistin could completely inhibit the growth of BL21(DE3) expressing mcr-1, which exhibited the most potent activity. In the enzymatic assay, we elucidate that 6p and 6q could target the MCR-1 to inhibit the activity of the protein. Additionally, a molecular docking study showed that 6p and 6q could interact with Glu246 and Thr285 via hydrogen bonds and occupy well the cavity of the MCR-1 protein. These results may provide a potential avenue to overcome colistin resistance, and provide some valuable information for further investigation on MCR-1 inhibitors.

8.
Food Funct ; 10(6): 3556-3566, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31157351

RESUMO

This study aimed to evaluate the functional and probiotic properties of Lactobacillus acidophilus SJLH001 (La-SJLH001) isolated from fermented food via mechanism analysis based on transcriptomics and culturomics. La-SJLH001 exhibited good tolerance to acid and bile salt conditions with anti-diabetic ability and cholesterol assimilation activity in vitro. Supplementation with La-SJLH001 also resulted in a significant reduction in host oral glucose and serum total cholesterol levels in vivo. Transcriptome profiles and qPCR analysis suggested that La-SJLH001 significantly regulated the transcription of key genes involved in glucose transportation, cholesterol metabolism, ion channels, and immune response, resulting in improved glucose homeostasis and cholesterol metabolism. La-SJLH001 significantly affected the structure of intestinal microbiota when analyzed by using culturomics coupled with MALDI-TOF MS. These results indicated that La-SJLH001 may be a mechanistic target for the control of diabetes with great potential in the application of probiotic products.

9.
iScience ; 16: 326-339, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31203188

RESUMO

Under extreme conditions or by genetic modification, pancreatic α-cells can regenerate and be converted into ß-cells. This regeneration holds substantial promise for cell replacement therapy in diabetic patients. The discovery of clinical therapeutic strategies to promote ß-cell regeneration is crucial for translating these findings into clinical applications. In this study, we reported that treatment with REMD 2.59, a human glucagon receptor (GCGR) monoclonal antibody (mAb), lowered blood glucose without inducing hypoglycemia in normoglycemic, streptozotocin-induced type 1 diabetic (T1D) and non-obesity diabetic mice. Moreover, GCGR mAb treatment increased the plasma glucagon and active glucagon-like peptide-1 levels, induced pancreatic ductal ontogenic α-cell neogenesis, and promoted α-cell proliferation. Strikingly, the treatment also increased the ß-cell mass in these two T1D models. Using α-cell lineage-tracing mice, we found that the neogenic ß-cells were likely derived from α-cell conversion. Therefore, GCGR mAb-induced α- to ß-cell conversion might represent a pre-clinical approach for improving diabetes therapy.

10.
Cancer Res ; 79(13): 3383-3394, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31040154

RESUMO

Homozygous deletion of methylthioadenosine phosphorylase (MTAP) is one of the most frequent genetic alterations in glioblastoma (GBM), but its pathologic consequences remain unclear. In this study, we report that loss of MTAP results in profound epigenetic reprogramming characterized by hypomethylation of PROM1/CD133-associated stem cell regulatory pathways. MTAP deficiency promotes glioma stem-like cell (GSC) formation with increased expression of PROM1/CD133 and enhanced tumorigenicity of GBM cells and is associated with poor prognosis in patients with GBM. As a combined consequence of purine production deficiency in MTAP-null GBM and the critical dependence of GSCs on purines, the enriched subset of CD133+ cells in MTAP-null GBM can be effectively depleted by inhibition of de novo purine synthesis. These findings suggest that MTAP loss promotes the pathogenesis of GBM by shaping the epigenetic landscape and stemness of GBM cells while simultaneously providing a unique opportunity for GBM therapeutics. SIGNIFICANCE: This study links the frequently mutated metabolic enzyme MTAP to dysregulated epigenetics and cancer cell stemness and establishes MTAP status as a factor for consideration in characterizing GBM and developing therapeutic strategies.

11.
Psychiatr Q ; 90(3): 471-480, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31079346

RESUMO

Cognitive deficits are a core feature of major depressive disorder (MDD). However, there are no previous studies that directly compare cognitive performance between first-episode drug-naive depressive patients (FDDP) and medicated depressive patients (MDP). Therefore, the aim of this study was to investigate whether there were the differences in cognitive functions between FDDP and MDP. Sixty-two FDDP, 111 MDP and 90 healthy controls were enrolled in a Chinese population. Cognitive functions were assessed using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). There were the differences in the RBANS total score (F = 26.55, p < 0.001), subscales of immediate memory (F = 3.95, p = 0.02), language (F = 54.11, p < 0.001) and delayed memory (F = 11.19, p = 0.001) among the three groups after controlling for gender, education, smoking and body mass index (BMI). These differences in the RBANS total score, subscales of language and delayed memory passed the Bonferroni corrections (all, p < 0.05). Compared to healthy controls, FDDP and MDP had poorer cognitive performance including the RBANS total score, and subscales of language and delayed memory (all, p < 0.05) after controlling for the variables. FDDP experienced greater language deficits than MDP (p < 0.05) after controlling for the variables. Education was correlated with the language score in FDDP (r = 0.61, p < 0.001). Multivariate regression analysis indicated that education was an independent contributor to the language score in FDDP (ß = 3.11, t = 5.48, p < 0.001). Our findings indicated that FDDP had poorer language performance than MDP. Moreover, education could influence the language performance in FDDP.

12.
Zhongguo Zhong Yao Za Zhi ; 44(8): 1654-1659, 2019 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-31090331

RESUMO

To explore the anti-platelet aggregation and anti-thrombotic mechanisms of Trichosanthis Fructus combined with aspirin based on network pharmacology and the validation of arteriovenous by pass model in rats. The databases of Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP),Drug Repositioning and Adverse Drug Reaction Chemical-Protein Interactome(DRAR-CPI),Universal Protein Resource(Uniprot) and the Database for Annotation,Visualization,and Integrated Discovery(DAVID) were used to predict protein targets and analyze biological pathway and signal pathway in the combination of Trichosanthis Fructus with aspirin. The effects of pretreatment with Trichosanthis Fructus pellets,aspirin pellets and their combination on thromboxane B2(TXB2),6-keto prostaglandin F1α(6-keto-PGF1α) and cyclic adenosine monophosphate(c AMP) in rat thrombotic model were studied. Through the study of network pharmacology,12 components of aspirin and Trichosanthis Fructus,including hydroxygenkwanin,quercetin and adenosine,were found to show the anti-platelet aggregation and anti-thrombosis mechanisms through9 common protein targets,such as SRC,RAC1,MAPK14,MAPK1,AKT1,and 14 common signaling pathways,such as VEGF signaling pathway. After the intervention with Trichosanthis Fructus pellets combined with aspirin pellets,the vascular endothslia growth factor(VEGF) signaling pathway can be activated to inhibit platelet aggregation and improve vascular endothelial function,and show the anti-platelet aggregation and anti-thrombosis mechanisms,which verify the results of the network pharmacology,and explain the anti-platelet aggregation and anti-thrombotic mechanisms of the combination of Trichosanthis Fructus pellets with aspirin pellets.


Assuntos
Aspirina/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Inibidores da Agregação de Plaquetas/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Trombose/tratamento farmacológico , Trichosanthes/química , 6-Cetoprostaglandina F1 alfa/metabolismo , Animais , AMP Cíclico/metabolismo , Frutas/química , Ratos , Transdução de Sinais , Tromboxano B2/metabolismo
13.
Medicine (Baltimore) ; 98(15): e15081, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30985660

RESUMO

This study aims to investigate the value of the ABCD score combined with the position of the offending vessel stenosis in predicting the risk of transient ischemic attack (TIA) to develop into cerebral infarction.The ABCD score and head magnetic resonance imaging + magnetic resonance angiography (MRA) results of 192 patients with TIA were retrospectively analyzed. With the 7th day as the endpoint time, these patients were divided into 3 groups, according to ABCD scores: low-risk group (n = 105), moderate-risk group (n = 60), and high-risk group (n = 27). Blood vessels were screened using head MRA results, and patients were accordingly divided into 2 groups: proximal vascular stenosis group (n = 71) and nonproximal vascular stenosis group (n = 171). Then, the association of the position of the intracranial vascular stenosis and ABCD score with short-term prognosis was analyzed.Based on the ABCD score, the incidence of cerebral infarction after 1 week was significantly higher in the high-risk group (85.7%) than in the moderate-risk group (16.7%) and low-risk group (1.9%), and the differences were statistically significant (P < .05). When the ABCD score was ≥4 points, the incidence of cerebral infarction after 1 week was significantly higher in the proximal vascular stenosis group (59.1%) than in the nonproximal vascular stenosis group (30.8%), and the difference was statistically significant (P < .05). When the ABCD score was <4 points, the incidence of cerebral infarction after 1 week in the proximal stenosis group (2%) was not significantly different from that in the nonproximal stenosis group (1.9%, P > .05).The ABCD score combined with proximal offending vessel stenosis can improve the short-term prediction of cerebral infarction in patients with TIA.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Infarto Cerebral/diagnóstico , Infarto Cerebral/etiologia , Ataque Isquêmico Transitório/complicações , Ataque Isquêmico Transitório/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Cerebral , Infarto Cerebral/epidemiologia , Infarto Cerebral/fisiopatologia , Constrição Patológica/complicações , Constrição Patológica/diagnóstico , Constrição Patológica/epidemiologia , Constrição Patológica/fisiopatologia , Imagem de Difusão por Ressonância Magnética , Progressão da Doença , Feminino , Humanos , Incidência , Ataque Isquêmico Transitório/epidemiologia , Ataque Isquêmico Transitório/fisiopatologia , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Medição de Risco
15.
Oncol Rep ; 41(4): 2089-2102, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30816528

RESUMO

Papillary renal cell carcinoma (PRCC) accounts for 15­20% of all kidney neoplasms and continually attracts attention due to the increase in the incidents in which it occurs. The molecular mechanism of PRCC remains unclear and the efficacy of drugs that treat PRCC lacks sufficient evidence in clinical trials. Therefore, it is necessary to investigate the underlying mechanism in the development of PRCC and identify additional potential anti­PRCC drugs for its treatment. The differently expressed genes (DEGs) of PRCC were identified, followed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses for functional annotation. Then, potential drugs for PRCC treatment were predicted by Connectivity Map (Cmap) based on DEGs. Furthermore, the latent function of query drugs in PRCC was explored by integrating drug­target, drug­pathway and drug­protein interactions. In total, 627 genes were screened as DEGs, and these DEGs were annotated using KEGG pathway analyses and were clearly associated with the complement and coagulation cascades, amongst others. Then, 60 candidate drugs, as predicted based on DEGs, were obtained from the Cmap database. Vorinostat was considered as the most promising drug for detailed discussion. Following protein­protein interaction (PPI) analysis and molecular docking, vorinostat was observed to interact with C3 and ANXN1 proteins, which are the upregulated hub genes and may serve as oncologic therapeutic targets in PRCC. Among the top 20 metabolic pathways, several significant pathways, such as complement and coagulation cascades and cell adhesion molecules, may greatly contribute to the development and progression of PRCC. Following the performance of the PPI network and molecular docking tests, vorinostat exhibited a considerable and promising application in PRCC treatment by targeting C3 and ANXN1.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Renais/genética , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/química , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Biologia Computacional , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/efeitos dos fármacos , Redes Reguladoras de Genes/genética , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Simulação de Acoplamento Molecular , Terapia de Alvo Molecular/métodos , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas/efeitos dos fármacos , Mapas de Interação de Proteínas/genética , Vorinostat/química , Vorinostat/farmacologia , Vorinostat/uso terapêutico
16.
Artigo em Inglês | MEDLINE | ID: mdl-30818756

RESUMO

Potassium (K) has been recognized as an essential element in intensive agricultural production systems, and deficiency of K usually results in a decrease in crop yields. The utilization of potassium-solubilizing bacteria (KSB) to increase the soluble K content in soil has been regarded as a desirable pathway to increase plant yields. Following the inoculation of KSB in the soil, potassium can be released (in the form of K⁺) and consumed by plants. This study aims to investigate and compare the distribution characteristics of potassium-solubilizing bacteria between forest and plantation soils in Myanmar. In this study, 14 KSB strains were isolated from rhizosphere samples collected from forest soil, as well as fertilized rubber tree rhizosphere soil and fertilized bare soil from a plantation. Broadleaf forests with high levels of canopy cover mainly comprised the forest environment, and rubber trees were planted in the plantation environment. The Chao and abundance-based coverage estimator (ACE) indices showed that the microbial abundance of the plantation soil was higher than that of the forest soil. According to the Illumina MiSeq sequencing analysis results, the Shannon index of the forest soil was lower while the Simpson index was higher, which demonstrated that the microbial diversity of the forest soil was higher than that of the plantation soil. Potassium-solubilizing test results showed that the strains E, I, M, and N were the most effective KSB under liquid cultivation conditions. Additionally, KSB only accounted for less than 5.47% of the total bacteria detected in either of the sample types, and the distribution of dominant KSB varied with the soil samples. As another result, the abundance of Pseudomonas spp. in S1 was higher than in S2 and S3, indicating a negative impact on the growth of Pseudomonas in the fertilized rubber tree rhizosphere soil. The significance of our research is that it proves that the increasing use of KSB for restoring soil is a good way to reduce the use of chemical fertilizers, which could further provide a relatively stable environment for plant growth.


Assuntos
Bactérias/metabolismo , Florestas , Hevea/microbiologia , Potássio/metabolismo , Microbiologia do Solo , Bactérias/classificação , Bactérias/isolamento & purificação , Biodiversidade , Fertilizantes , Hevea/crescimento & desenvolvimento , Hevea/metabolismo , Mianmar , Rizosfera , Solo/química
17.
Bioorg Chem ; 86: 679-685, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30831529

RESUMO

In the course of studying the components from the roots of Sophora flavescens, eight new unusual biflavonoids consisting of a flavanone fused with a dihydrochalcone skeleton were isolated. These new chemical structures were elucidated by means of UV, IR, HRESIMS, NMR and ECD spectroscopic data and a comparison of experimental ECD spectra with calculated ECD spectra. Some compounds were subjected to an antidiabetic bioassay on human recombinant PTP1B inhibition, and showed strong inhibitory activity.

18.
Nanotechnology ; 30(27): 275101, 2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30856613

RESUMO

Despite decades of efforts, non-invasive sensitive detection of small malignant brain tumors still remains challenging. Here we report a dual-modality 124I-labeled gold nanostar (124I-GNS) probe for sensitive brain tumor imaging with positron emission tomography (PET) and subcellular tracking with two-photon photoluminescence (TPL) and electron microscopy (EM). Experiment results showed that the developed nanoprobe has potential to reach sub-millimeter intracranial brain tumor detection using PET scan, which is superior to any currently available non-invasive imaging modality. Microscopic examination using TPL and EM further confirmed that GNS nanoparticles permeated the brain tumor leaky vasculature and accumulated inside brain tumor cells following systemic administration. Selective brain tumor targeting by enhanced permeability and retention effect and ultrasensitive imaging render 124I-GNS nanoprobe promise for future brain tumor-related preclinical and translational applications.

19.
Int J Mol Sci ; 20(6)2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30889878

RESUMO

Diacylglycerol kinase (DGK) is an enzyme that plays a pivotal role in abiotic and biotic stress responses in plants by transforming the diacylglycerol into phosphatidic acid. However, there is no report on the characterization of soybean DGK genes in spite of the availability of the soybean genome sequence. In this study, we performed genome-wide analysis and expression profiling of the DGK gene family in the soybean genome. We identified 12 DGK genes (namely GmDGK1-12) which all contained conserved catalytic domains with protein lengths and molecular weights ranging from 436 to 727 amino acids (aa) and 48.62 to 80.93 kDa, respectively. Phylogenetic analyses grouped GmDGK genes into three clusters-cluster I, cluster II, and cluster III-which had three, four, and five genes, respectively. The qRT-PCR analysis revealed significant GmDGK gene expression levels in both leaves and roots coping with polyethylene glycol (PEG), salt, alkali, and salt/alkali treatments. This work provides the first characterization of the DGK gene family in soybean and suggests their importance in soybean response to abiotic stress. These results can serve as a guide for future studies on the understanding and functional characterization of this gene family.


Assuntos
Diacilglicerol Quinase/genética , Perfilação da Expressão Gênica , Genômica , Família Multigênica , Soja/enzimologia , Soja/genética , Estresse Fisiológico/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Cromossomos de Plantas/genética , Diacilglicerol Quinase/química , Diacilglicerol Quinase/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Especificidade de Órgãos/genética , Filogenia , Regiões Promotoras Genéticas/genética , Domínios Proteicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Frações Subcelulares/metabolismo
20.
Proc Natl Acad Sci U S A ; 116(13): 6308-6312, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30858324

RESUMO

Liquid biopsies, based on cell free DNA (cfDNA) and proteins, have shown the potential to detect early stage cancers of diverse tissue types. However, most of these studies were retrospective, using individuals previously diagnosed with cancer as cases and healthy individuals as controls. Here, we developed a liquid biopsy assay, named the hepatocellular carcinoma screen (HCCscreen), to identify HCC from the surface antigen of hepatitis B virus (HBsAg) positive asymptomatic individuals in the community population. The training cohort consisted of individuals who had liver nodules and/or elevated serum α-fetoprotein (AFP) levels, and the assay robustly separated those with HCC from those who were non-HCC with a sensitivity of 85% and a specificity of 93%. We further applied this assay to 331 individuals with normal liver ultrasonography and serum AFP levels. A total of 24 positive cases were identified, and a clinical follow-up for 6-8 mo confirmed four had developed HCC. No HCC cases were diagnosed from the 307 test-negative individuals in the follow-up during the same timescale. Thus, the assay showed 100% sensitivity, 94% specificity, and 17% positive predictive value in the validation cohort. Notably, each of the four HCC cases was at the early stage (<3 cm) when diagnosed. Our study provides evidence that the use of combined detection of cfDNA alterations and protein markers is a feasible approach to identify early stage HCC from asymptomatic community populations with unknown HCC status.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/diagnóstico , Detecção Precoce de Câncer/métodos , Antígenos de Superfície da Hepatite B/sangue , Biópsia Líquida/métodos , Neoplasias Hepáticas/diagnóstico , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/patologia , Ácidos Nucleicos Livres , Vírus da Hepatite B , Hepatite B Crônica , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/patologia , Sensibilidade e Especificidade , Ultrassonografia
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