Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 727
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-34625339

RESUMO

OBJECTIVE: Early screening and intervention are crucial for the prevention and treatment of cervical cancer. TruScreen is a real-time, intelligent, pathological diagnostic technology designed for cervical cancer screening. The aim of this study was to evaluate the clinical value of TruScreen in screening for cervical lesions. STUDY DESIGN: A total of 458 women aged between 25 and 65 years were recruited to receive cervical cancer screening, including human papillomavirus (HPV) testing, cytological testing using the ThinPrep cytology test (TCT), and TruScreen from December 2018 to January 2020. The clinical performance of TruScreen, alone and in combination with HPV testing, was evaluated to detect cervical intraepithelial neoplasia grade 2 or worse (CIN2+ or CIN3+). RESULTS: For detection of CIN2+, the sensitivity and specificity of TruScreen were 83.78% and 78.86%, respectively. The specificity of TruScreen was significantly higher than those of HPV testing (50.59%, P < 0.001) and TCT (55.58%, P < 0.001). In high-risk HPV-positive women, the specificity of HPV testing combined with TruScreen was significantly higher than that of HPV testing combined with TCT (50% vs 39.9%, P = 0.004). The sensitivity of HPV testing combined with TruScreen was comparable to that of HPV testing combined with TCT (93.94% vs 87.88%, P = 0.625). Similar patterns were also observed for CIN3+ cases. CONCLUSION: TruScreen has the potential for screening high-grade cervical precancerous lesions and may replace cytological tests as a cervical cancer screening method in China to avoid subjectivity in the interpretation of cytological tests and requirements by pathologists.

2.
Pharmacol Ther ; : 108018, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34626676

RESUMO

Classically, the fate of internalized membrane receptors includes receptor degradation and receptor recycling. However, recent findings have begun to challenge these views. Much research demonstrated that many internalized membrane receptors can trigger distinct signal activation rather than being desensitized inside the cell. Here, we introduce the concept of "internalized activation" which not only represents a new mode of receptor activation, but also endows the new fate for receptor internalization (form death to life). The new activation mode and fate of membrane receptor are ubiquitous and have unique theoretical significance. We systematically put forward the features, process, and regulation of "internalized activation" and its significance in signal transduction and diseases. "Internalized activation" will provide a completely new understanding for the theory of receptor activation, internalization and novel drug targets for precision medicine.

3.
Food Funct ; 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34636389

RESUMO

Curcumin is a polyphenol substance considered to be effective in the treatment of a number of neurodegenerative diseases. However, details regarding the exact mechanisms for the protective effects of curcumin in neuropsychiatric disorders, like depression, remain unknown. In the pathogenesis of major depressive disorder (MDD) it appears that dysregulation of oxidative stress and immune systems, particularly within the hippocampal region, may play a critical role. Here, we show that pre-treatment with curcumin (40 mg kg-1) alleviates depression-like behaviors in a LPS-induced rat model of depression, effects which were accompanied with suppression of oxidative stress and inflammation and an inhibition of neuronal apoptosis in the hippocampal CA1 region, and results from ultramicrostructure electrophysiological experiments revealed that the curcumin pre-treatment significantly prevented excessive synaptic loss and enhanced synaptic functioning in this LPS-induced rat model. In addition, curcumin attenuated the increases in levels of miR-146a-5p and decreases in the expression of p-ERK signaling that would normally occur within CA1 regions of these depressed rats. Taken together, these results demonstrated that curcumin exerts neuroprotective and antidepressant activities by suppressing oxidative stress, neural inflammation and their related effects upon synaptic dysregulation. One of the mechanisms for these beneficial effects of curcumin appears to involve the miR-146a-5p/ERK signaling pathway within the hippocampal CA1 region. These findings not only elucidated some of the mechanisms underlying the neuroprotective/antidepressant effects of curcumin, but also suggested a role of curcumin as a potential therapeutic strategy for depression.

4.
Artigo em Chinês | MEDLINE | ID: mdl-34628845

RESUMO

Cancer stem cells (CSCs), as a few amount of tumors, have infinite replication, self-renewal, differentiation and regeneration of cell subsets with tumorigenicity, have close relationship with tumor occurrence and recurrence, which can be found in head and neck squamous cell carcinoma (HNSCC). One of the important measures to improve the patient prognosis is monitoring cancer stem cells and timely clinical intervention. Biomarker detection of cancer stem cells is an important method for clinical monitoring of cancer stem cells. This article reviews the biomarkers of CSCs in HNSCC, which is consist of membrane surface markers, non-coding RNAs, target genes and proteins.


Assuntos
Neoplasias de Cabeça e Pescoço , Biomarcadores , Humanos , Recidiva Local de Neoplasia , Células-Tronco Neoplásicas , Carcinoma de Células Escamosas de Cabeça e Pescoço
5.
Artigo em Inglês | MEDLINE | ID: mdl-34585353

RESUMO

Microcystis is a well-known toxic cyanobacterium in eutrophic environments, and an increasing number of Microcystis blooms have emerged in salty reservoirs and coastal rivers. This study observed that many Microcystis were identified in a coastal river in June 2020. The relative abundance of Microcystis decreased from 81.2 to 10.2% in the sampling sites from a salinity of 0 (Sal. 0) to a salinity of 12 (Sal. 12). Hepatotoxic microcystins (MCs) were identified in the coastal river and its estuary. Of the samples, those with a salinity of 5 (Sal. 5) had the highest concentration of MCs at 7.81 ± 0.67 µg L-1. In a saline water simulation experiment, the results showed that salt inhibited Microcystis (M.) aeruginosa growth, enhanced the activity levels of superoxide dismutase (SOD) and catalase (CAT) and stimulated microcystin production. Transcription analysis showed that the expression levels of the psaB and rbcL genes controlling photosymbiotic processes were downregulated, and capD and csaBgene-related polysaccharide productions were upregulated by salt incubation. Notably, metabolism analysis showed that the total polysaccharides, proteins and small molecular matter, such as sucrose, methionine and N-acetyl-D-glucosamine, in the Microcystis cells increased substantially to resist the extracellular hyperosmotic pressure caused by the high salinity levels in culture. These findings indicate that increased salt in a natural aquatic body shifts the phytoplankton community by influencing the physiological metabolism of cyanobacteria and poses a high risk of microcystin exposure during cyanobacterial blooms in coastal rivers.

6.
Analyst ; 146(19): 5942-5950, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34570841

RESUMO

The study of complex mixtures is very important for exploring the evolution of natural phenomena, but the complexity of the mixtures greatly increases the difficulty of material information extraction. Image perception-based machine-learning techniques have the ability to cope with this problem in a data-driven way. Herein, we report a 2D-spectral imaging method to collect matter information from mixture components, and the obtained feature images can be easily provided to deep convolutional neural networks (CNNs) for establishing a spectral network. The results demonstrated that a single CNN trained end-to-end from the proposed images can directly accomplish synchronous measurement of multi-component samples using only raw pixels as inputs. Our strategy has some innate advantages, such as fast data acquisition, low cost, and simple chemical treatment, suggesting that it can be extensively applied in many fields, including environmental science, biology, medicine, and chemistry.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , Misturas Complexas , Diagnóstico por Imagem , Processamento de Imagem Assistida por Computador
7.
Plant Cell Physiol ; 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34523687

RESUMO

Jasmonate (JA)-induced plant senescence was mainly studied with the dark/starvation-promoted system using detached leaves, yet the induction of whole-plant senescence by JA remains largely unclear. This work reports the finding of a JA-induced whole-plant senescence of tobacco under light/non-starvation condition and the investigation of underlying regulations. MeJA (methyl jasmonate) treatment induces the whole-plant senescence of tobacco in a light-intensity-dependent manner, which is suppressed by silencing of NtCOI1 that encodes the receptor protein of JA-Ile (the bioactive derivative of JA). MeJA treatment could induce the senescence-specific cysteine protease gene SAG12 and another cysteine protease gene SAG-L1 to high expression levels in the detached leaf patches under dark condition, but failed to induce their expression in tobacco whole-plants under light condition. Furthermore, MeJA attenuates RuBisCo activase (RCA) level in the detached leaves, but has no effect on this protein in the whole-plant under light condition. Genome-wide transcriptional assay also supports the presence of a differential regulatory pattern of senescence-associated-genes (SAGs) in the MeJA-induced whole-plant senescence under non-starvation condition and results in the finding of a chlorophylase activity increase in this process. We also observed that the MeJA-induced senescence of tobacco whole-plant is reversible, which is accompanied with a structural change of chloroplasts. This work provides novel insights into the JA-induced plant senescence under non-starvation condition and is helpful to dissect the JA-synchronized process of whole-plant senescence.

8.
J Microbiol ; 59(10): 898-910, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34491521

RESUMO

During a study of the marine actinobacterial biodiversity, a large number of Brevibacterium strains were isolated. Of these, five that have relatively low 16S rRNA gene similarity (98.5-99.3%) with validly published Brevibacterium species, were chosen to determine taxonomic positions. On the basis of 16S rRNA gene sequence analysis and BOX-PCR fingerprinting, strains o2T, YB235T, and WO024T were selected as representative strains. Genomic analyses, including average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH), clearly differentiated the three strains from each other and from their closest relatives, with values ranging from 82.8% to 91.5% for ANI and from 26.7% to 46.5% for dDDH that below the threshold for species delineation. Strains YB235T, WO024T, and o2T all exhibited strong and efficient decolorization activity in congo red (CR) dyes, moderate decolorization activity in toluidine blue (TB) dyes and poor decolorization in reactive blue (RB) dyes. Genes coding for peroxidases and laccases were identified and accounted for these strains' ability to effectively oxidize a variety of dyes with different chemical structures. Mining of the whole genome for secondary metabolite biosynthesis gene clusters revealed the presence of gene clusters encoding for bacteriocin, ectoine, NRPS, siderophore, T3PKS, terpene, and thiopeptide. Based on the phylogenetic, genotypic and phenotypic data, strains o2T, YB235T and WO024T clearly represent three novel taxa within the genus Brevibacterium, for which the names Brevibacterium limosum sp. nov. (type strain o2T = JCM 33844T = MCCC 1A09961T), Brevibacterium pigmenatum sp. nov. (type strain YB235T = JCM 33843T = MCCC 1A09842T) and Brevibacterium atlanticum sp. nov. (type strain WO024T = JCM 33846T = MCCC 1A16743T) are proposed.

9.
Pol J Microbiol ; 70(3): 401-404, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34584534

RESUMO

SARS-CoV-2 was found in a recovered patient's stool specimen by combining quantitative reverse transcription PCR (qRT-PCR) and genome sequencing. The patient was virus positive in stool specimens for at least an additional 15 days after he was recovered, whereas respiratory tract specimens were negative. The discovery of the complete genome of SARS-CoV-2 in the stool sample of the recovered patient demonstrates a cautionary warning that the potential mode of the virus transmission cannot be excluded through the fecal-oral route after viral clearance in the respiratory tract.


Assuntos
COVID-19/virologia , Convalescença , Fezes/virologia , Genoma Viral , SARS-CoV-2/genética , Sequenciamento Completo do Genoma , Adulto , COVID-19/diagnóstico por imagem , COVID-19/transmissão , China , Tosse/virologia , Febre/virologia , Humanos , Masculino , SARS-CoV-2/isolamento & purificação , Tomografia Computadorizada por Raios X
10.
Ecotoxicol Environ Saf ; 225: 112728, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34500383

RESUMO

The types, contents, and microstructures of clay minerals play important roles in controlling the adsorption and desorption of ion-absorbed type rare earth ores and heavy metals. By selecting a typical rare earth ore profile, we conducted a leaching experiment and used XRD (X-ray diffraction) and TEM (Transmission electron microscopy) analyses to determine the clay mineral types and microstructural changes after various leaching periods. The XRD phase analyses showed that the main minerals in the simulated rare earth ore were quartz, potassium feldspar, kaolinite, and illite. TEM images showed that the mineral aggregates were broken, disintegrated, and transformed by the leaching process, and a large number of moire fringes were visible. With continuous leaching, REEs (Rare Earth Elements) were gradually re-solved and leached. The results of the leaching experiment indicate that fine-grained minerals in rare earth ores, such as potassium feldspar and clay minerals, migrated downward with the leaching solution. Leaching also promoted the alteration of potassium feldspar to clay minerals, as well as mutual alteration of clay minerals. Under acidic or neutral conditions during the early stage, potassium feldspar was altered to kaolinite or illite, whereas during the middle and late stages of leaching it was altered as follows: illite → mixed-layer illite-kaolinite → kaolinite → mixed-layer kaolinite-illite → illite. This transformation has an important effect on the release of REEs and heavy metals and provides insights into improving the leaching process and explaining heavy metal pollution in rare earth mining areas.


Assuntos
Metais Pesados , Metais Terras Raras , Argila , Metais Terras Raras/análise , Minerais , Mineração
11.
J Med Chem ; 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34538051

RESUMO

Triple-negative breast cancer (TNBC) is highly aggressive with very limited treatment options due to the lack of efficient targeted therapies and thus still remains clinically challenging. Targeting transcription-associated cyclin-dependent kinases to remodel transcriptional regulation shows great promise in cancer therapy. Herein, we report the synthesis, optimization, and evaluation of new series of heterobifunctional molecules as highly selective and efficacious CDK9 degraders, enabling potent inhibition of TNBC cell growth and rapidly targeted degradation of CDK9. Moreover, the most potent CDK9 degrader (compound 45) induces cell apoptosis in vitro and inhibits tumor growth in the MDA-MB-231 TNBC model. Furthermore, the RNA-seq, immunohistochemistry assays demonstrate that the CDK9 degrader downregulates the downstream targets, such as MYC, at the transcriptional level, resulting apoptosis in TNBC cells. Our work establishes that 45 is a highly potent and efficacious CDK9 degrader for targeting transcription regulation, which represents an effective strategy and great potential as a new targeted therapy for TNBC.

12.
Chemosphere ; 287(Pt 1): 132125, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34523460

RESUMO

Organophosphate flame retardant (OPFR) pollution in marine environment has attracted increasing attention in recent years. Coral reefs are regarded as significant marine ecosystems, however, research on OPFR contamination in coral reefs is limited. In the present work, 9 OPFR compounds were analyzed in fish samples collected from the Zhubi Reef and Yongshu Reef of the Nansha Islands, South China Sea, to evaluate the biomagnification and potential threats of OPFRs in the coral reef ecosystems. ∑OPFR concentrations in the coral reef fish ranged from 38.7 to 2090 ng/g lipid weight (lw), with an average of 420 ± 491 ng/g lw. Alkyl OPFRs were more abundant than chlorinated OPFRs and aryl OPFRs. Individually, TBEP and TCPP were the two most abundant OPFR compounds. Biomagnification potential was indicated for TCPP, TCEP, TBP, TBEP and TEHP along the marine food web, with trophic magnification factors being greater than one. The estimated dietary intakes of OPFRs via coral fish consumption were 0-1.11 ng/kg bw/d and 0.01-2.06 ng/kg bw/d, respectively, for rural and urban residents. Additionally, the hazard quotients of OPFR compounds ranged from 2 × 10-7 to 7.41 × 10-5 for rural residents and from 4 × 10-7 to 1.37 × 10-4 for urban residents. Although the risk to human health from exposure to OPFRs via consuming coral reef fish from the South China Sea was low, further investigation of these chemicals is still recommended.

13.
J Hazard Mater ; 416: 126168, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492944

RESUMO

As an issue of great concern, microplastics pollution has emerged as a key environmental challenge of our time. The atmosphere is a significant compartment in the global cycle of microplastics, however, studies on the transport and deposition of airborne microplastics is limited. In the present work, atmospheric wet and dry deposition of microplastics were analyzed over one year in an urban environment of megacity Guangzhou, China. The atmospheric deposition fluxes of microplastics ranged from 51 to 178 particles/m2/d (mean: 114 ± 40 particles/m2/d). Fibers, fragments, films and microbeads were observed in the deposition samples, with fibers being the most abundant microplastics, accounting for 77.6 ± 19.1% of the total. The chemical composition of microplastics were identified using micro Fourier transform infrared spectrometer. 78.7% of the fibrous microplastics were derived from petrochemicals and most were polyethylene terephthalate (polyester), suggesting that textiles (e.g., clothes and curtains) were likely the main source. The results of back-trajectory analysis indicated that city rivers may act as secondary sources of airborne microplastics. Though no significant correlation was found between atmospheric microplastic deposition and meteorological factors such as rainfall and wind events, these factors were suggested to be positive drivers for the transport and deposition of airborne microplastic.


Assuntos
Microplásticos , Poluentes Químicos da Água , Atmosfera , Monitoramento Ambiental , Plásticos , Rios , Poluentes Químicos da Água/análise
14.
Mol Plant ; 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34509639

RESUMO

The interaction between plant and soil environment affects plant survival and evolution. In modern agriculture, frequent application of herbicide may induce changes in plants and results in unfavorable consequences. Here we report the characterization of a mutant called rtp1 with strong resistance to the widely used herbicides paraquat and diquat. This mutant is semi-dominant, and the mutant gene encodes a MATE (multidrug and toxic compound extrusion) family protein DTX6. The charge property of the 311th residue of DTX6 is critical for the paraquat and diquat resistance of Arabidopsis. The wild type protein with glycine 311 conferred weak paraquat and diquat resistance. Mutation of glycine311 to negatively charged amino acids (G311E and G311D) largely increased the paraquat and diquat resistance of plants, while mutation to positively charged amino acids (G311R and G311K) compromised the resistance. DTX6 was localized in endomembrane trafficking system. It may participate in the endosomal sorting to vacuole and to plasma membrane. The V-ATPase inhibitor ConA treatment reduced the paraquat resistance of the rtp1 mutant. Paraquat release and uptake assays demonstrated that DTX6 was involved in both exocytosis and vacuole sequestration of paraquat. There was functional redundancy between DTX5 and DTX6, and the dtx5 dtx6 double mutant was more sensitive to paraquat and diquat than the wild type plants. Our work revealed a potential mechanism for evolved herbicide resistance in weeds and also provided a promising gene in manipulating plants' herbicide resistance.

16.
Chem Commun (Camb) ; 57(81): 10560-10563, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34557886

RESUMO

The mu-opioid receptor (MOR) regulates the neuronal pathways involved in pain, reward, and respiration. To increase our understanding of MOR's roles in these pathways, there is a need to detect opioids at cellular resolution. Here, we engineered an improved opioid-sensor, called M-SPOTIT2, which is 11x brighter than our previously engineered M-SPOTIT1.1. We engineered M-SPOTIT2 by adding the amino acids YNSH, located near the fluorophore of the enhanced green fluorescent protein, to the circular permuted green fluorescent protein in M-SPOTIT2. M-SPOTIT2 is 11x brighter than our previously engineered M-SPOTIT1.1 in HEK293T cell culture and 2.7x brighter in neuronal culture. M-SPOTIT2 will potentially be useful for the detection of opioids in cell culture for drug screening and the detection of opioids at cellular resolution in animal tissues. By using M-SPOTIT2, researchers can gain more understanding about the mechanisms of addiction, respiratory suppression, and pain-modulation involved in opioid signaling.

17.
Toxicol Appl Pharmacol ; 429: 115700, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34464674

RESUMO

3,3'-diindolylmethane (DIM) is a dimer compound converted from Indoly-3-carbinol that had been studied as promising chemo-preventive agent against breast cancer. In this study, we observed that proportion of CD133+Nanog+ subpopulation in MCF-7 cells was significantly increased after DIM administration with up-regulated AKT activity by using CyTOF assay. SPADE analysis revealed this stem-like subpopulation exhibited apoptosis-resistance property against DIM treatment. By combining with AKT inhibitor AZD5363, DIM induced CD133 expression could be suppressed. In addition, a combination treatment of MCF-7 and MDA-MB-231 breast cancer cells with DIM and AZD5363 showed synergistic decreases in cell proliferation and induced apoptosis. Furthermore, results from imaging flow cytometry suggested that FoxO3a nuclear localization and PUMA expression could be improved by combination of AZD5363 with DIM. Taken together, the above observations suggested that the combination of AZD5363 with DIM could be developed as potential therapy for breast cancer.

19.
Bioorg Chem ; 116: 105291, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34438122

RESUMO

In this study, twenty novel cinnamic acid magnolol derivatives were synthesized, and screened for their anti-hyperglycemic potential. All synthesized compounds exhibited good to moderate α-glucosidase and α-amylase inhibitory activities with IC50 values: 5.11 ± 1.46-90.26 ± 1.85 µM and 4.27 ± 1.51-49.28 ± 2.54 µM as compared to the standard acarbose (IC50: 255.44 ± 1.89 µM and 80.33 ± 2.95 µM, respectively). Compound 6j showed the strongest inhibitory activity against α-glucosidase (IC50 = 5.11 ± 1.46 µM) and α-amylase (IC50 = 4.27 ± 1.51 µM). Kinetic study indicated that compound 6j was reversible and a mixed type inhibitor against α-glucosidase and α-amylase. In silico studies revealed the binding interaction between 6j and two enzymes, respectively. Finally, cells cytotoxicity assay revealed that compound 6j showed low toxicity against 3 T3-L1 cells and HepG2 cells.

20.
J Sci Food Agric ; 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389997

RESUMO

BACKGROUND: Optimum cultivation and management measures are needed to increase the phosphorus (P) absorption efficiency of crops for sustainable agricultural production. Previous studies indicated that leguminous crops can promote P absorption by neighboring gramineous crops. In this study, we isolated and screened the phosphate-solubilizing bacteria (PSB) from soybean rhizosphere under a maize-soybean intercropping system in Southwest China, and nine PSBs with high P-solubilizing ability were identified. RESULTS: 16S rDNA sequencing and phylogenetic analysis showed that these PSBs belong mainly to Bacillus and Pseudomonas. The phosphate solubility of Bacillus aryabhattai B8W22 reached 388.62 µg mL-1 . High-performance liquid chromatographic analysis showed that each strain could secrete a large quantity of organic acids, including oxalic acid, malonic acid, citric acid and succinic acid. In addition, all strains produced indole acetic acid (IAA) and siderophores that could promote plant growth. Seed germination experiments testified that PSBs isolated in this study have an innate ability to promote plant growth. The plant culture pot experiment further illustrated that soil acid phosphatase (ACP) activity and available P content, as well as plant P uptake, increased significantly with PSBs inoculation. CONCLUSION: PSBs from the rhizosphere soil of intercropped soybean could secrete organic acids that increase the solubilization of unavailable P, improve soil ACP activity and P availability, and produce IAA and siderophores that promote maize seed germination and seedling growth. Our findings indicate the PSBs from soybean rhizosphere have significant potential to reduce the application of chemical phosphate fertilizers and to promote sustainable agricultural development. © 2021 Society of Chemical Industry.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...