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1.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(5): 1403-1410, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34627417

RESUMO

OBJECTIVE: To establish cytarabine-resistant acute lymphoblastic leukemia (ALL) cell lines and investigate its possible resistant mechanism. METHODS: Low-concentration cytarabine (Ara-C) continuously induced and cultured Jurkat and Nalm-6 cells to construct cytarabine-resistant cell lines Jurkat/Ara-C and Nalm-6/Ara-C. The cell viability was detected by CCK-8 assay, and the distribution of cell cycle was detected by flow cytometry. Real-time fluorescence quantitative PCR was used to detect the mRNA expression levels of multidrug resistant gene and Ara-C metabolic enzymes. The expression levels of cyclin were detected by Western blot. RESULTS: Jurkat/Ara-C and Nalm-6/Ara-C drug-resistant cell lines were successfully established, the resistance index of which was 1 973.908±161.163 and 7 231.643± 1 190.624, respectively. Drug-resistant cell lines had no cross-resistance to commonly used chemotherapeutic drugs, such as doxorubicin. Flow cytometry showed that the ratio of G0/G1 phase in Jurkat/Ara-C cells increased but G2/M phase decreased (P<0.05), while the cell cycle distribution of Nalm-6/Ara-C cells did not change in comparison with Nalm-6 cells. The results of real-time quantitative PCR showed that the expression of deoxycytidine kinase (DCK) and cytidine deaminase (CDA) were significantly down-regulated in drug-resistant cells (P<0.05), MRP was up-regulated in Nalm-6/Ara-C cells (P<0.05), while MDR1, LRP and BCRP did not increase in comparison with parental cells. Western blot analysis revealed that cyclinB1 was significantly under-expressed in drug-resistant cells (P<0.05), while cyclinD1 did not change, when compared with parental cells. CONCLUSION: Cytarabine-resistant ALL cell lines are successfully established by using low concentration continuous induction method, and its drug-resistant mechanism may be related to the deficiencies of DCK and cyclinB1.


Assuntos
Citarabina , Leucemia-Linfoma Linfoblástico de Células Precursoras , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Linhagem Celular , Citarabina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Humanos , Proteínas de Neoplasias
2.
Int J Mol Sci ; 22(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34638610

RESUMO

Teosinte branched1/cycloidea/proliferating cell factor (TCP) gene family members are plant-specific transcription factors that regulate plant growth and development by controlling cell proliferation and differentiation. However, there are no reported studies on the TCP gene family in Dendrobium catenatum Lindl. Here, a genome-wide analysis of TCP genes was performed in D. catenatum, and 25 TCP genes were identified. A phylogenetic analysis classified the family into two clades: Class I and Class II. Genes in the same clade share similar conserved motifs. The GFP signals of the DcaTCP-GFPs were detected in the nuclei of tobacco leaf epidermal cells. The activity of DcaTCP4, which contains the miR319a-binding sequence, was reduced when combined with miR319a. A transient activity assay revealed antagonistic functions of Class I and Class II of the TCP proteins in controlling leaf development through the jasmonate-signaling pathway. After different phytohormone treatments, the DcaTCP genes showed varied expression patterns. In particular, DcaTCP4 and DcaTCP9 showed opposite trends after 3 h treatment with jasmonate. This comprehensive analysis provides a foundation for further studies on the roles of TCP genes in D. catenatum.

3.
Nat Commun ; 12(1): 5915, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34625565

RESUMO

Automatic medical image segmentation plays a critical role in scientific research and medical care. Existing high-performance deep learning methods typically rely on large training datasets with high-quality manual annotations, which are difficult to obtain in many clinical applications. Here, we introduce Annotation-effIcient Deep lEarning (AIDE), an open-source framework to handle imperfect training datasets. Methodological analyses and empirical evaluations are conducted, and we demonstrate that AIDE surpasses conventional fully-supervised models by presenting better performance on open datasets possessing scarce or noisy annotations. We further test AIDE in a real-life case study for breast tumor segmentation. Three datasets containing 11,852 breast images from three medical centers are employed, and AIDE, utilizing 10% training annotations, consistently produces segmentation maps comparable to those generated by fully-supervised counterparts or provided by independent radiologists. The 10-fold enhanced efficiency in utilizing expert labels has the potential to promote a wide range of biomedical applications.

4.
Sheng Wu Gong Cheng Xue Bao ; 37(9): 3334-3347, 2021 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-34622640

RESUMO

Cordycepin is the key active component of medicinal fungus Cordyceps militaris, and it shows multiple functional activities such as anti-tumor and anti-virus. Cordycepin was conventionally produced by liquid fermentation of C. militaris, but the long production cycle and the low productivity constrained its development and application. In this study, two key genes for cordycepin biosynthesis (ScCNS1 and ScCNS2) were introduced into Saccharomyces cerevisiae S288C, producing 67.32 mg/L cordycepin at 240 h. Analysis of gene expression profiles indicated that ZWF1, PRS4, ADE4, ScCNS1 and ScCNS2 which encode enzymes involved in pentose phosphate pathway, purine metabolism and cordycepin biosynthesis pathway, were significantly up-regulated in the late phage of fermentation. Optimization of fermentation medium determined that 50 g/L initial glucose followed by feeding, supplemented with 5 mmol/L Cu²âº and 1.0 g/L adenine were the best condition. Fed-batch fermentation using the engineered yeast in a 5 L stirred fermenter produced 137.27 mg/L cordycepin at 144 h, with a productivity up to 0.95 mg/(L·h) reached, which was 240% higher than that of the control.


Assuntos
Cordyceps , Saccharomyces cerevisiae , Meios de Cultura , Desoxiadenosinas , Saccharomyces cerevisiae/genética
5.
Mater Horiz ; 8(6): 1776-1782, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34594564

RESUMO

Bacterial wound infections are a threat to public health. Although antibiotics currently provide front-line treatments for bacterial infections, the development of drug resistance coupled with the defenses provided through biofilm formation render these infections difficult, if not impossible, to cure. Antimicrobials from natural resources provide unique antimicrobial mechanisms and are generally recognized as safe and sustainable. Herein, an all-natural antimicrobial platform is reported. It is active against bacterial biofilms and accelerates healing of wound biofilm infections in vivo. This antimicrobial platform uses gelatin stabilized by photocrosslinking using riboflavin (vitamin B2) as a photocatalyst, and carvacrol (the primary constituent of oregano oil) as the active antimicrobial. The engineered nanoemulsions demonstrate broad-spectrum antimicrobial activity towards drug-resistant bacterial biofilms and significantly expedite wound healing in an in vivo murine wound biofilm model. The antimicrobial activity, wound healing promotion, and biosafety of these nanoemulsions provide a readily translatable and sustainable strategy for managing wound infections.

7.
Nanoscale ; 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34622911

RESUMO

Zinc-ion batteries (ZIBs) are a main focus worldwide for their potential use in large-scale energy storage due to their abundant resources, environmental friendliness, and high safety. However, the cathode materials of ZIBs are limited, requiring a stable host structure and fast Zn2+ channel diffusion. Here, we develop a strategy for the intercalation of polyethylene glycol (PEG) to facilitate Zn2+ intercalation and to suppress the dissolution of vanadium in V2O5. In particular, PEG-V2O5 shows a high capacity of 430 mA h g-1 at a current density of 0.1 A g-1 as well as excellent 100 mA h g-1 specific capacity after 5000 cycles, with a high current density of 10.0 A g-1. A reversible capacity of 81 mA h g-1 can even be achieved with a low temperature of -20 °C at a current density of 2.0 A g-1 after 3500 cycles. The superior electrochemical performance comes from the intercalation of PEG molecules, which can improve kinetic transport and structural stability during the cycling process. The Zn2+ storage mechanism, which provides essential guidelines for the development of high-performance ZIBs, can be found through various ex situ characterization technologies and density functional density calculations.

8.
Hum Psychopharmacol ; : e2820, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597436

RESUMO

BACKGROUND: Whether a single low-dose ketamine infusion may have rapid antidepressant and antisuicidal effects in patients with treatment-resistant double depression remains unclear. METHODS: This study enrolled 35 patients with treatment-resistant double depression, 12 of whom received 0.5 mg/kg ketamine, 11 received 0.2 mg/kg ketamine, and 12 received normal saline as a placebo. The patients were assessed using the 17-item Hamilton Rating Scale for Depression (HDRS) prior to the initiation of infusions, at 40 and 240 min post-infusion, and sequentially on Days 2-7 and on Day 14 after ketamine or placebo infusions. RESULTS: A single 0.5 mg/kg ketamine infusion had rapid antidepressant (p = 0.031, measured by the HDRS) and antisuicidal (p = 0.033, measured by the HDRS item 3 scores) effects in patients with treatment-resistant double depression. However, 0.2 mg/kg ketamine was insufficient to exert rapid antidepressant and antisuicidal effects in this patient population with severe and chronic illness. DISCUSSION: In this patient population, the commonly used dose of 0.5 mg/kg was sufficient. Additional studies are required to investigate whether repeated infusions of low-dose ketamine may also maintain antidepressant and antisuicidal effects in patients with treatment-resistant double depression.

10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 39(5): 560-565, 2021 Oct 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34636204

RESUMO

OBJECTIVES: This study aimed to compare the postoperative outcome of the new and classical muscular reconstruction technique combined with nasal internal-fixation method for secondary deformity post unilateral cleft lip repair. A rationale is provided for the further surgical improvement of secondary deformities. METHODS: Sixty patients aged 4-18 years with secondary unilateral cleft lip-nose deformity were involved in this research. The deformities of 28 patients were repaired using the muscular force balance technique through nasal internal fixation method, and 32 were repaired using classical muscular reconstruction technique. Two-dimensional analysis was used to evaluate the nose-lip morphology of pre- and post-operative patients through standardized photographs seven days after surgery. RESULTS: Compared with preoperative nasal morphology in the muscular force balance technique group, the 7-days postoperative results of this group showed the significantly improved short-term outcomes in the correction of columellar deflection, alar rim angle, nasal shape, and the symmetry of alar base width, nostril width, nostril height, alar rim angle (P<0.05). CONCLUSIONS: The new muscular reconstruction technique with nasal internal-fixation method has a significant effect on nasal repair.


Assuntos
Fenda Labial , Rinoplastia , Fenda Labial/cirurgia , Humanos , Nariz/cirurgia , Período Pós-Operatório , Resultado do Tratamento
11.
Artigo em Inglês | MEDLINE | ID: mdl-34609826

RESUMO

In this work, we fabricated cobalt-doped carbon quantum dots (Co-CQDs) by a one-pot hydrothermal method with cobalt tetraphenylporphyrin and 1,2-ethanediamine as precursors. The morphology and structure of the Co-CQDs were characterized through transmission electron microscopy, X-ray diffraction spectra, Fourier transform infrared, and X-ray photoelectron spectra. The Co-CQDs emitted intense blue luminescence under ultraviolet irradiation and exhibited a typical excitation-dependent emission property. Moreover, they can act as a fluorescent probe for the detection of Fe3+ and ascorbic acid (AA) with high selectivity and sensitivity through an "on-off-on" mode. The limit of detection (LOD) of Fe3+ was measured as 38 µM (S/N = 3). The quenched emission of carbon quantum dots can be recovered with the addition of ascorbic acid (AA) to the Co-CQDs/Fe3+ system. The change of fluorescence was linear with the concentration of AA (0.6-1.6 mM) with the LOD of 18 µM. Furthermore, the Co-CQDs exhibited high oxidase-like catalytic behavior, which could convert transparent 3,3',5,5'-tetramethylbenzidine (TMB) into blue ox-TMB by dissolved oxygen. After adding ascorbic acid to the Co-CQDs/TMB system, the blue color of the solution faded due to the reduction of blue ox-TMB to colorless TMB. Based on this phenomenon, the Co-CQDs were capable of detecting AA (10-400 µM) with the LOD of 0.27 µM. The fluorometric and colorimetric assays based on the Co-CQDs for the AA detection were then successfully applied in fresh fruits. Furthermore, the high biocompatibility of the Co-CQDs against HeLa cells was verified by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Thus, the Co-CQDs could be used as a powerful tool for the detection of AA in real samples through a dual-mode method.

13.
Viral Immunol ; 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34647822

RESUMO

Pseudorabies (PR), the causative agent of Aujeszky's disease, has rapidly increased in recent years and has caused significant economic losses. To understand the seroprevalence and epidemiological characteristics of PR in Tianjin, China, a total of 23,627 blood and 1,093 tissue samples were collected from 228 pig farms during January 2010 to December 2018. The Pseudorabies virus (PRV) glycoprotein E (gE) antibody was tested by enzyme-linked immunosorbent assay (ELISA), and wild-type PRV (WT PRV) was detected by gE-polymerase chain reaction (PCR). Macroscopic and microscopic lesions were observed in tissue samples. The results showed that 46.70% of the serum samples and 49.76% of pig farms were seropositive for PRV gE antibody based on the ELISA results, and 13.54% of the tissue samples were positive for WT PRV detected by PCR. The positive rate of serum samples increased rapidly after 2011 and reached 62.40% in 2013. Although it gradually decreased from 2014 to 2018, the positive rate of serum samples remained at a high level. The positive rate of pig farms showed the same trend. Moreover, after 2011, the detection rate of WT PRV was increased rapidly and was significantly higher than in 2010 and 2011. Macroscopic and microscopic lesions were observed in various tissues during histopathological examination. Based on univariate analysis, the increased risk of seropositivity was associated with the immune status and infection in sows and fattening pigs. These findings demonstrate that PR was prevalent in the region of Tianjin, China. These epidemiological data can assist in the control of PR.

14.
Nano Lett ; 21(19): 8385-8392, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34606292

RESUMO

The microbolometer is the cornerstone device for imaging in the long-wavelength infrared range (LWIR) at room temperature. The state-of-the-art commercial microbolometers usually have a large thermal time constant (TTC) of over 10 ms, limited by their substantial device heat capacity. Moreover, the minimal pixel size of state-of-the-art bolometer is around 10 µm by 10 µm to ensure sufficient power absorption per pixel. Here, we demonstrate an ultrafast silicon nanomembrane microbolometer with a small heat capacity of around 1.9 × 10-11J/K, which allows for its operation at a speed of over 10 kHz, corresponding to a TTC of less than 16 µs. Moreover, a compact diabolo antenna is leveraged for efficient LWIR light absorption, enabling the downscaling of the active area size to 6.2 µm by 6.2 µm. Because of the complementary metal oxide semiconductor (CMOS)-compatible fabrication processes, our demonstration here may lead to a future high-resolution and high-speed LWIR imaging solution.


Assuntos
Semicondutores , Silício , Raios Infravermelhos , Óxidos
15.
Crit Rev Food Sci Nutr ; : 1-19, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34494479

RESUMO

Food allergy is a serious health problem affecting more than 10% of the human population worldwide. Medical treatments for food allergy remain limited because immune therapy is risky and costly, and anti-allergic drugs have many harmful side effects and can cause drug dependence. In this paper, we review natural bioactive substances capable of alleviating food allergy. The sources of the anti-allergic substances reviewed include plants, animals, and microbes, and the types of substances include polysaccharides, oligosaccharides, polyphenols, phycocyanin, polyunsaturated fatty acids, flavonoids, terpenoids, quinones, alkaloids, phenylpropanoids, and probiotics. We describe five mechanisms involved in anti-allergic activities, including binding with epitopes located in allergens, affecting the gut microbiota, influencing intestinal epithelial cells, altering antigen presentation and T cell differentiation, and inhibiting the degranulation of effector cells. In the discussion, we present the limitations of existing researches as well as promising advances in the development of anti-allergic foods and/or immunomodulating food ingredients that can effectively prevent or alleviate food allergy. This review provides a reference for further research on anti-allergic materials and their hyposensitizing mechanisms.

16.
Food Chem ; 369: 131000, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34492613

RESUMO

Starch retrogradation involves nucleation and crystal growth steps, while their relative contribution to the overall retrogradation kinetics and relations with starch fine molecular structures have not been elucidated. In this study, a consecutive reaction kinetics model (CRK) was developed to fit long-term retrogradation kinetics curves for 10 rice starches with distinct molecular structures. Starch chain-length distributions (CLDs) and melting enthalpy kinetics curves for these starches were obtained from our published data. It was shown that these melting enthalpy kinetics curves can be satisfactorily deconvoluted by the CRK model into a combination of nucleation and crystal growth curves. Correlation analysis between CRK model-fitted parameters with starch CLDs showed that starch retrogradation nucleation and crystal growth steps were controlled by distinct starch fine molecular structures. These results have practical applications, as it enables a separate regulation of nucleation and crystal growth steps during retrogradation process of starch-based foods for desirable nutritional properties.

17.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(9): 922-926, 2021.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34535207

RESUMO

OBJECTIVES: To study the risk factors associated with the need for mechanical ventilation in children with Guillain-Barré syndrome (GBS). METHODS: The medical data of 107 children with GBS were retrospectively reviewed. According to whether mechanical ventilation was required, the children were divided into a mechanical ventilation group with 16 children and a non-mechanical ventilation group with 91 children. The risk factors associated with the need for mechanical ventilation in children with GBS were identified by a multivariate logistic regression analysis. RESULTS: Among the 107 children, 16 (15.0%) required mechanical ventilation. Compared with the non-mechanical ventilation group, the mechanical ventilation group had a significantly higher proportion of children with facial and/or bulbar muscle weakness, a significantly shorter duration from the onset to the peak of the disease, and a significantly higher Hughes Functional Grading Scale score at the first visit (P<0.05). Facial and/or bulbar muscle weakness and short duration from the onset to the peak of the disease were risk factors associated with the need for mechanical ventilation in children with GBS (OR=5.053 and 1.239 respectively, P<0.05). CONCLUSIONS: Facial and/or bulbar muscle weakness and short duration from the onset to the peak of the disease may increase the risk of mechanical ventilation in children with GBS. Citation.


Assuntos
Síndrome de Guillain-Barré , Respiração Artificial , Criança , Síndrome de Guillain-Barré/terapia , Humanos , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
18.
Sci Total Environ ; 805: 150295, 2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-34536874

RESUMO

Few studies have comprehensively evaluated the impacts of microbial decomposing inoculants on greenhouse gas emissions and economic profit from paddy fields under different water regimes. Here, this study evaluated the effects of microbial decomposing inoculant treatments (straw returning without or with microbial decomposing inoculants (S and SMD)) on rice yield, CH4 and N2O emissions, economic profit and net ecosystem economic profit (NEEP) from paddy fields under different water regimes (continuous flooding (CF) and alternate wetting and drying irrigation (AWD)) in central China with a two-year field experiment. Compared with S treatment, SMD treatment significantly increased the rice yield and crop water productivity by 6.6-7.2% and 5.6-7.9%, respectively. AWD treatment significantly enhanced the crop water productivity by 56.9-73.7% while did not affect rice yield relative to CF treatment. Regardless of water regimes, SMD treatment did not affect N2O emissions, but significantly increased CH4 emissions by 13.8-39.6% relative to S treatment, resulting in a remarkable enhancement of global warming potential by 13.5-32.5%. Compared with S treatment, SMD treatment improved the economic profit and NEEP. By contrast, AWD treatment significantly increased N2O emissions by 19.1-64.8% compared with CF treatment, but significantly reduced CH4 emissions by 35.3-79.1%. Accordingly, AWD treatment significantly decreased the global warming potential by 33.4-73.9% compared with CF treatment. In addition, AWD treatment resulted in 39.9-96.4% higher economic profit and 48.0-124.4% higher NEEP relative to CF treatment. In summary, AWD treatment is a sustainable water regime that can maintain rice yield, mitigate global warming potential, and increase economic income. However, regardless of water regimes, SMD treatment led to higher rice yield and economic profit, as well as higher global warming potential than S treatment, suggesting that other appropriate treatments of crop straw are needed to mitigate CH4 emissions while improving economic profit for rice sustainable production.

19.
PLoS Genet ; 17(9): e1009432, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34506495

RESUMO

Epigenetic alterations occur as organisms age, and lead to chromatin deterioration, loss of transcriptional silencing and genomic instability. Dysregulation of the epigenome has been associated with increased susceptibility to age-related disorders. In this study, we aimed to characterize the age-dependent changes of the epigenome and, in turn, to understand epigenetic processes that drive aging phenotypes. We focused on the aging-associated changes in the repressive histone marks H3K9me3 and H3K27me3 in C. elegans. We observed region-specific gain and loss of both histone marks, but the changes are more evident for H3K9me3. We further found alteration of heterochromatic boundaries in aged somatic tissues. Interestingly, we discovered that the most statistically significant changes reflected H3K9me3-marked regions that are formed during aging, and are absent in developing worms, which we termed "aging-specific repressive regions" (ASRRs). These ASRRs preferentially occur in genic regions that are marked by high levels of H3K9me2 and H3K36me2 in larval stages. Maintenance of high H3K9me2 levels in these regions have been shown to correlate with a longer lifespan. Next, we examined whether the changes in repressive histone marks lead to de-silencing of repetitive DNA elements, as reported for several other organisms. We observed increased expression of active repetitive DNA elements but not global re-activation of silent repeats in old worms, likely due to the distributed nature of repetitive elements in the C. elegans genome. Intriguingly, CELE45, a putative short interspersed nuclear element (SINE), was greatly overexpressed at old age and upon heat stress. SINEs have been suggested to regulate transcription in response to various cellular stresses in mammals. It is likely that CELE45 RNAs also play roles in stress response and aging in C. elegans. Taken together, our study revealed significant and specific age-dependent changes in repressive histone modifications and repetitive elements, providing important insights into aging biology.

20.
Dermatology ; : 1-7, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34474411

RESUMO

BACKGROUND: Proton pump inhibitors (PPIs) are among the most widely used drugs. Little is known about the association between PPI use and risk of psoriasis. OBJECTIVE: To investigate the association between PPI use and subsequent psoriasis risk. METHODS: We included participants from the Taiwan National Health Insurance Research Database. Patients with PPI use and an incidence of psoriasis (n = 5,756) were assigned to the case cohort and 1:1 matched to controls. PPI use was defined as >30 cumulative defined daily doses (cDDDs); PPI nonuse was defined as ≤30 cDDDs. Logistic regression was used for the analyses. RESULTS: There was a significant association between PPI use and psoriasis risk. The confounder-adjusted odd ratios (95% confidence interval [CI]) were 1.52 (1.31-1.76) and 1.54 (1.22-1.93) for patients with 120-365 cDDDs and >365 cDDDs, respectively, compared with PPI nonusers. Stratified analyses based on PPI type showed that exposure to lansoprazole (OR, 1.25; 95% CI, 1.11-1.41) was associated with subsequent psoriasis risk. CONCLUSIONS: PPI use might be associated with an increased risk of developing psoriasis or as an epiphenomenon. Further prospective studies are needed to elucidate the association and underlying mechanisms.

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