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1.
J Sci Food Agric ; 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538610

RESUMO

BACKGROUND: Pure gelatin film usually exhibits characteristics of brittle and hydrophilic, which limit its widely use in food packing fields. Gelatin/oxidized poly (2-hydroxyethylacrylate) (G/OP) composite films were prepared using casting techniques, the aim of this research was to investigate the effects of OP on the structures and properties of the G/OP composite films. RESULTS: The Fourier-transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy results indicated that the G/OP films retained their original secondary structure and random coiled conformation. However, the surface and cross-sectional morphologies of the G/OP films were rougher than those of pure gelatin films, cracks and agglomerates appeared with increasing OP dosage. The remarkable transparency of the G/OP film at 280 nm indicated the excellent ultraviolet (UV) light barrier properties of the film, which inhibited UV-light-induced food oxidation. Moreover, the addition of OP decreased the water content and water solubility and considerably increased the water contact angle of pure gelatin films from 78.8° to 116.2° (a maximum increase of 37.5°). This suggested that OP modification improved the hydrophobicity of gelatin films. Furthermore, the inclusion of OP significantly promoted the flexibility of gelatin films, thereby improving their brittleness. CONCLUSIONS: The UV light barrier properties, hydrophobicity, and flexibility of gelatin films were improved via OP modification, the produced G/OP composite films have the potential to be used in food packaging. This article is protected by copyright. All rights reserved.

2.
Clin Nucl Med ; 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35543631

RESUMO

ABSTRACT: Widespread cutaneous involvement of Langerhans cell histiocytosis is rare. Here, we report the case of a patient with cutaneous Langerhans cell histiocytosis, which showed a large number of small high 18F-FDG-avid foci all over the body skin on PET/CT, accompanied with involved lymph nodes in bilateral axillas.

3.
Zhongguo Zhong Yao Za Zhi ; 47(9): 2392-2399, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35531686

RESUMO

With the rise of incidence, fatality rate, and number of young cases, diabetes mellitus has been one of the seven major diseases threatening human health. Although many antidiabetic drugs(oral or for injection) are available, the majority have serious side effects during the long-term use. Thus, it is of particularly vital to develop new drugs with low risk and definite effect. Psoraleae Fructus, a traditional medicinal widely used in the folk, has hypoglycemic, anti-osteoporosis, antitumor, estrogen-like, and anti-inflammatory effects. Thus, it has great clinical application potential. Chinese medicine and the active ingredients, characterized by multiple targets, multiple pathways, and multiple effects in the treatment of diabetes mellitus, have distinct advantages in clinical application. However, the safety of Chinese medicine remains to be a challenge, and one of keys is to clarifying the mechanism of a single Chinese medicinal and its active ingredients. With the method of literature research, this study summarized and analyzed the hypoglycemic mechanisms of Psoraleae Fructus and its main active ingredients over the last decade: regulating glucose metabolism, improving insulin resistance, and directly acting on pancreatic ß-cells. The result is expected to serve as a reference for further research on the effects of Psoraleae Fructus and its main chemical constituents in lowering blood glucose and preventing diabetes mellitus and the clinical application.


Assuntos
Medicamentos de Ervas Chinesas , Osteoporose , Psoralea , Medicamentos de Ervas Chinesas/farmacologia , Frutas/química , Humanos , Hipoglicemiantes/análise , Hipoglicemiantes/farmacologia , Osteoporose/tratamento farmacológico , Psoralea/química
4.
Environ Sci Technol ; 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35512288

RESUMO

Microorganisms residing in the human respiratory tract can be exhaled, and they constitute a part of environmental microbiotas. However, the expiratory microbiota community and its associations with environmental microbiotas remain poorly understood. Here, expiratory bacteria and fungi and the corresponding microbiotas from the living environments were characterized by DNA amplicon sequencing of residents' exhaled breath condensate (EBC) and environmental samples collected from 14 residences in Nanjing, China. The microbiotas of EBC samples, with a substantial heterogeneity, were found to be as diverse as those of skin, floor dust, and airborne microbiotas. Model fitting results demonstrated the role of stochastic processes in the assembly of the expiratory microbiota. Using a fast expectation-maximization algorithm, microbial community analysis revealed that expiratory microbiotas were differentially associated with other types of microbiotas in a type-dependent and residence-specific manner. Importantly, the expiratory bacteria showed a composition similarity with airborne bacteria in the bathroom and kitchen environments with an average of 12.60%, while the expiratory fungi showed a 53.99% composition similarity with the floor dust fungi. These differential patterns indicate different relationships between expiratory microbiotas and the airborne microbiotas and floor dust microbiotas. The results here illustrated for the first time the associations between expiratory microbiotas and indoor microbiotas, showing a potential microbial exchange between the respiratory tract and indoor environment. Thus, improved hygiene and ventilation practices can be implemented to optimize the indoor microbial exposome, especially in indoor bathrooms and kitchens.

5.
BMC Bioinformatics ; 23(1): 161, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513780

RESUMO

BACKGROUND: With the development of modern sequencing technology, hundreds of thousands of single-cell RNA-sequencing (scRNA-seq) profiles allow to explore the heterogeneity in the cell level, but it faces the challenges of high dimensions and high sparsity. Dimensionality reduction is essential for downstream analysis, such as clustering to identify cell subpopulations. Usually, dimensionality reduction follows unsupervised approach. RESULTS: In this paper, we introduce a semi-supervised dimensionality reduction method named scSemiAE, which is based on an autoencoder model. It transfers the information contained in available datasets with cell subpopulation labels to guide the search of better low-dimensional representations, which can ease further analysis. CONCLUSIONS: Experiments on five public datasets show that, scSemiAE outperforms both unsupervised and semi-supervised baselines whether the transferred information embodied in the number of labeled cells and labeled cell subpopulations is much or less.

6.
Food Chem X ; 14: 100310, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35492251

RESUMO

The objective of this study was to develop an effective recovery technology of odor-active compounds (OACs) to improve the flavor quality of instant Pu-erh tea (IPT) based on their released behaviors. Salting-out re-distillation (SRD) combined with sensory-directed analysis was developed. The contributing factors, including the soaking time of tea, recovery volume of condensed water of first distillation, amount of sodium chloride, recovery volume of condensed water of SRD, and re-use times of sodium chloride, were studied systematically. Under optimized conditions, 41 OACs were recovered in the first distillation, and the total recovery rate was 83.94%. Forty-one OACs were recovered via SRD, and the total recovery rate reached 72.29%, significantly better than membrane method (33.46%). The IPT prepared by adding OACs that recovered via SRD showed strong aroma attributes intensities and good coordination. This developed method can provide a more effective scheme to improve the flavor quality of IPT.

7.
Oxid Med Cell Longev ; 2022: 5652586, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35368865

RESUMO

Metabolic changes have been suggested to be a hallmark of tumors and are closely associated with tumorigenesis. In a previous study, we demonstrated the role of lactate dehydrogenase in regulating abnormal glucose metabolism in pituitary adenomas (PA). As the key organelle of oxidative phosphorylation (OXPHOS), mitochondria play a vital role in the energy supply for tumor cells. However, few attempts have been made to elucidate mitochondrial metabolic homeostasis in PA. Dynamin-related protein 1 (Drp1) is a member of the dynamin superfamily of GTPases, which mediates mitochondrial fission. This study is aimed at investigating whether Drp1 affects the progression of PA through abnormal mitochondrial metabolism. We analyzed the expression of dynamin-related protein 1 (Drp1) in 20 surgical PA samples. The effects of Drp1 on PA growth were assessed in vitro and in xenograft models. We found an upregulation of Drp1 in PA samples with a low proliferation index. Knockdown or inhibition of Drp1 enhanced the proliferation of PA cell lines in vitro, while overexpression of Drp1 could reversed such effects. Mechanistically, overexpressed Drp1 damaged mitochondria by overproduction of reactive oxygen species (ROS), which induced mitochondrial OXPHOS inhibition and decline of ATP production. The energy deficiency inhibited proliferation of PA cells. In addition, overexpressed Drp1 promoted cytochrome c release from damaged mitochondria into the cytoplasm and then activated the downstream caspase apoptotic cascade reaction, which induced apoptosis of PA cells. Moreover, the decreased ATP production induced by Drp1 overexpressing activated the AMPK cellular energy stress sensor and enhanced autophagy through the AMPK-ULK1 pathway, which might play a protective role in PA growth. Furthermore, overexpression of Drp1 repressed PA growth in vivo. Our data indicates that Drp1-mediated mitochondrial metabolic dysfunction inhibits PA growth by affecting cell proliferation, apoptosis, and autophagy. Selectively targeting mitochondrial metabolic homeostasis stands out as a promising antineoplastic strategy for PA therapy.


Assuntos
Dinaminas/metabolismo , Neoplasias Hipofisárias , GTP Fosfo-Hidrolases/metabolismo , Humanos , Dinâmica Mitocondrial , Fosforilação Oxidativa
8.
Front Pharmacol ; 13: 887890, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35462900

RESUMO

Depression is one of the main diseases that lead to disability and loss of ability to work. As a traditional Chinese medicine, Zhi-zi-chi decoction is utilized to regulate and improve depression. However, the research on the antidepressant mechanism and efficacy material basis of Zhi-zi-chi decoction has not been reported yet. Our previous research has found that Zhi-Zi-chi decoction can reduce glutamate-induced oxidative stress damage to PC 12 cells, which can exert a neuroprotective effect, and the antidepressant effect of Zhi-Zi-chi decoction was verified in CUMS rat models. In this study, the animal model of depression was established by chronic unpredictable mild stimulation combined with feeding alone. The brain metabolic profile of depressed rats was analyzed by the method of metabolomics based on ultra-performance liquid chromatography-quadrupole/time-of-flight mass. 26 differential metabolites and six metabolic pathways related to the antidepressant of Zhi-zi-chi decoction were screened and analyzed. The targeted metabolism of the glutathione metabolic pathway was analyzed. At the same time, the levels of reactive oxygen species, superoxide dismutase, glutathione reductase, glutathione peroxidase in the brain of depressed rats were measured. Combined with our previous study, the antioxidant effect of the glutathione pathway in the antidepressant effect of Zhi-zi-chi decoction was verified from the cellular and animal levels respectively. These results indicated that Zhi-zi-chi decoction exerted a potential antidepressive effect associated with reversing the imbalance of glutathione and oxidative stress in the brain of depressed rats.

9.
Front Oncol ; 12: 739631, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463323

RESUMO

The invasiveness and high proliferation rate of growth hormone-secreting pituitary adenomas (GHPAs) are closely related to poor prognosis in patients. We previously reported that abnormal glycolysis participates in this process; however, the role of mitochondria in the invasion and proliferation of GHPAs remains unknown. In the current study, stereological methods were first used to quantitatively calculate the number and morphology of mitochondria. The results revealed that the numbers, volumes and membrane areas of mitochondria were decreased in invasive GHPAs (IGHPAs) samples compared to noninvasive GHPAs (NIGHPAs) samples. Furthermore, significantly downregulated mRNA and protein levels of dynamin-related protein 1 (Drp1) were detected in IGHPAs, but no notable changes in fusion related molecules (Mfn1, Mfn2 and OPA1) were detected, suggesting that the abnormal mitochondrial dynamics in IGHPAs are characterized by hypofission. Mitochondrial hypofission caused by Mdivi-1, a specific Drp1 inhibitor, enhanced the invasion and proliferation of GH3 cell lines and primary cells from patients with GHPAs in vitro and in vivo, while overexpression of Drp1 reversed these processes. Mechanistically, mitochondrial hypofission might activate signal transducer and activator of transcription 3 (STAT3). Specifically, elevated nuclear pSTAT3Y705 may promote GH3 cell invasion by upregulating the activity of matrix metalloproteinase 2/9, and elevated mitochondrial pSTAT3S727 may promote GH3 cell proliferation by inhibiting the mitochondria-dependent apoptotic pathway. Taken together, our findings suggest that mitochondrial hypofission induced by Drp1 might strengthen the invasion and proliferation of GHPA tumor cells by activating STAT3, providing us with a new perspective on how mitochondria regulate the development of IGHPAs.

10.
Support Care Cancer ; 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35488009

RESUMO

PURPOSE: We assessed the effectiveness of "timing it right" (TIR) applications in patients undergoing radiotherapy for head and neck cancer through a carefully designed TIR intervention program. The assessment in this study emphasized the impact of the TIR intervention on the unmet needs and psychological pain of patients with head and neck cancer at different stages of radiotherapy. METHODS: In total, 140 radiotherapy patients were randomly recruited into two study groups: (1) the TIR intervention group received routine nursing follow-up and comprehensive nursing intervention based on TIR, and (2) the control group received routine nursing care. Assessments were conducted at baseline, before discharge, and 3 months and 6 months after discharge. The comprehensive needs and psychological pain of patients with radiotherapy were measured using the Comprehensive Needs Assessment Tool in Cancer for Patients (CNAT) and the Distress Thermometer (DT), respectively. A linear mixed model was applied to analyze the effects. RESULTS: A total of 137 patients completed the study. Compared to the control group, the TIR group showed significant improvements in information needs, health and psychological problems, healthcare staff, physical symptoms, health facilities and services, religious/spiritual support, and psychological pain (F=8.503, p=0.004; F=1.896, p=0.003; F=12.422, p<0.001; F=9.634, p=0.001; F=7.310, p=0.006; F=1.684, p=0.009; F=1.692, p=0.041). In addition to practical support, the remaining indicators differed significantly by time point, group, and group-time interaction. CONCLUSIONS: The patient support application based on TIR can effectively address unmet needs and improve psychological pain, supporting TIR as an effective psychological management and intervention strategy for radiotherapy patients in the early stage of long-term rehabilitation. TRIAL REGISTRATION: Chictr.org.cn Chi CTR2100047960.

11.
Food Chem ; 388: 133016, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35486987

RESUMO

Panda bean protein isolate (PDPI), a legume-protein with Chinese characteristics, was investigated as an alternative potential food protein source. The physicochemical characteristics, functional properties and amino-acid composition of PDPI were determined and compared with soybean (SPI) and pea protein isolate (PPI). Results showed that PDPI was rich in phaseolin (mainly 7S vicilin), and its molecular weight was lower than that of SPI and PPI which were rich in legumin and vicilin. In comparison to SPI and PPI, PDPI showed the lowest solubility, surface-charge and surface-tension at pH 3.0, 7.0 and 9.0, but it exhibited comparable or even superior functionalities, especially in emulsifying and foaming abilities, gelling behaviour, rheological and textural properties. Moreover, the amino-acid composition and protein efficiency ratio of PDPI were excellent. The knowledge gained in the study is expected to provide reliable scientific science data for the potential application of PDPI in the food industry.

12.
Am J Clin Nutr ; 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35470384

RESUMO

BACKGROUND: Recent preclinical research strongly suggests that dietary sugars can enhance colorectal tumorigenesis by direct action, particularly in the proximal colon that unabsorbed fructose reaches. OBJECTIVES: We aimed to examine long-term consumption of sugar-sweetened beverages (SSBs) and total fructose in relation to incidence and mortality of colorectal cancer (CRC) by anatomic subsite. METHODS: We followed 121,111 participants from 2 prospective US cohort studies, the Nurses' Health Study (1984-2014) and Health Professionals Follow-Up Study (1986-2014), for incident CRC and related death. Cox proportional hazards regression was used to compute HRs and 95% CIs. RESULTS: During follow-up, we documented 2733 incident cases of CRC with a known anatomic location, of whom 901 died from CRC. Positive associations of SSB and total fructose intakes with cancer incidence and mortality were observed in the proximal colon but not in the distal colon or rectum (Pheterogeneity ≤ 0.03). SSB consumption was associated with a statistically significant increase in the incidence of proximal colon cancer (HR per 1-serving/d increment: 1.18; 95% CI: 1.03, 1.34; Ptrend = 0.02) and a more pronounced elevation in the mortality of proximal colon cancer (HR: 1.39; 95% CI: 1.13, 1.72; Ptrend = 0.002). Similarly, total fructose intake was associated with increased incidence and mortality of proximal colon cancer (HRs per 25-g/d increment: 1.18; 95% CI: 1.03, 1.35; and 1.42; 95% CI: 1.12, 1.79, respectively). Moreover, SSB and total fructose intakes during the most recent 10 y, rather than those from a more distant period, were associated with increased incidence of proximal colon cancer. CONCLUSIONS: SSB and total fructose consumption were associated with increased incidence and mortality of proximal colon cancer, particularly during later stages of tumorigenesis.

13.
Biosensors (Basel) ; 12(4)2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35448289

RESUMO

Hollow carbon nitride nanosphere (HCNS) was synthesized via the hard template method to improve the fluorescence characteristics, drug delivery ability, and photocatalytic activity. Blue fluorescent HCNS was utilized as a quenching agent and an internal reference to combine with Cy5-labelled aptamer (Cy5-Apt), resulting in an off-on fluorescence aptasensing method for the detection of Salmonella typhimurium (S. typhimurium). Under optimum conditions, this fluorescence assay presented a linear range from 30 to 3 × 104 CFU mL-1 with a detection limit of 13 CFU mL-1. In addition, HCNS was also used as a drug carrier to load chloramphenicol (Cap) molecules. The Cap-loading amount of HCNS could reach 550 µg mg-1 within 24 h, whereas the corresponding Cap-release amount is 302.5 µg mg-1 under acidic and irradiation conditions. The integration of photocatalyst with antibiotic could endow HCNS-Cap with better disinfection performance. The bactericidal efficiency of HCNS-Cap (95.0%) against S. typhimurium within 12 h was better than those of HCNS (85.1%) and Cap (72.9%). In addition, selective disinfection of S. typhimurium was further realized by decorating aptamer. Within 4 h, almost all S. Typhimurium were inactivated by HCNS-Cap-Apt, whereas only 13.3% and 48.2% of Staphylococcus aureus and Escherichia coli cells were killed, respectively. Therefore, HCNS is a promising bio-platform for aptamer-based fluorescence detection and selective disinfection of S. typhimurium.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanosferas , Antibacterianos , Técnicas Biossensoriais/métodos , Desinfecção , Nitrilas , Salmonella typhimurium
14.
Cell Death Dis ; 13(4): 408, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484101

RESUMO

Triple-negative breast cancer (TNBC) is a highly lethal disease due to aggressive clinical phenotype and the lack of validated therapeutic targets. Our recent quantitative proteomic analysis of 90 cases of TNBC tissues and 72 cases of matched adjacent normal tissues revealed that the expression levels of BPTF-associated protein of 18 KDa (BAP18), a component of the MLL1 and NURF chromatin complexes, were upregulated in TNBC tissues relative to normal tissues. However, the biological function and the underlying mechanism of BAP18 in TNBC progression remain unexplored. Here, we report that BAP18 promoted TNBC cell proliferation, migration, and invasion in vitro and xenograft tumor growth and lung colonization in vivo. Mechanistic investigations revealed that S100 calcium-binding protein A9 (S100A9), a member of the S100 protein family that is frequently upregulated in breast tumors and acts as an oncogenic driver in breast cancer progression, was a downstream target gene of BAP18. BAP18 was recruited to histone H3 trimethylation at lysine 4 (H3K4me3)-marked promoter of S100A9 and enhanced its promoter activities. Notably, knockdown of BAP18 by short hairpin RNA in TNBC cells suppressed xenograft tumor growth in mice, the noted effect was partially reverted by re-expression of S100A9 in BAP18-depleted cells. Taken together, these results suggest that BAP18 promotes TNBC progression through, at least in part, transcriptional activation of oncogene S100A9, and represents a potential therapeutic target for TNBC.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Neoplasias de Mama Triplo Negativas , Animais , Calgranulina B/genética , Calgranulina B/metabolismo , Linhagem Celular Tumoral , Cromatina , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Oncogenes/genética , Proteômica , Ativação Transcricional , Neoplasias de Mama Triplo Negativas/patologia
15.
Int J Mol Sci ; 23(8)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35457106

RESUMO

Increasing rapeseed yield has always been a primary goal of rapeseed research and breeding. However, flowering time is a prerequisite for stable rapeseed yield and determines its adaptability to ecological regions. MIKC-type MADS-box (MICK) genes are a class of transcription factors that are involved in various physiological and developmental processes in plants. To understand their role in floral transition-related pathways, a genome-wide screening was conducted with Brassica napus (B. napus), which revealed 172 members. Using previous data from a genome-wide association analysis of flowering traits, BnaSVP and BnaSEP1 were identified as candidate flowering genes. Therefore, we used the CRISPR/Cas9 system to verify the function of BnaSVP and BnaSEP1 in B. napus. T0 plants were edited efficiently at the BnaSVP and BnaSEP1 target sites to generate homozygous and heterozygous mutants with most mutations stably inherited by the next generation. Notably, the mutant only showed the early flowering phenotype when all homologous copies of BnaSVP were edited, indicating functional redundancy between homologous copies. However, no changes in flowering were observed in the BnaSEP1 mutant. Quantitative analysis of the pathway-related genes in the BnaSVP mutant revealed the upregulation of SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) and FLOWERING LOCUS T (FT) genes, which promoted early flowering in the mutant. In summary, our study created early flowering mutants, which provided valuable resources for early maturing breeding, and provided a new method for improving polyploid crops.


Assuntos
Brassica napus , Brassica napus/metabolismo , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Estudo de Associação Genômica Ampla , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Melhoramento Vegetal , Poliploidia
16.
Transplantation ; 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35389371

RESUMO

BACKGROUND: Many risk-prediction models for lung transplantation are centered on recipient characteristics and do not account for impact of donor and transplant-related factors or only examine short-term outcomes (eg, predicted 1-y survival). We sought to develop a comprehensive model guiding recipient-donor matching. METHODS: We identified double lung transplant recipients (≥12 y old) in the United Network for Organ Sharing Registry (2005-2020) to develop a risk scoring tool. Cohort was divided into derivation and validation sets. A total of 42 recipient, donor, and transplant factors were included in the analysis. Lasso method was used for variable selection. Survival was estimated using Cox-proportional hazard models. An interactive web-based tool was developed for clinical use. RESULTS: A derivation cohort (n = 10 660) informed the model with 13-recipient, 4-donor, and 2-transplant variables. Adjusted risk scores were computed for every transplant and grouped into 3 clusters. Model-estimated survival probabilities were similar to the observed in the validation cohort (n = 4464) for all clusters. The mortality increases for medium- and high-risk groups was similar in both derivation and validation cohorts (C statistics for 1-, 5-, and 10-y survival were 0.67, 0.64, and 0.72, respectively). The web-based application estimated 1-, 5-, 10-y survival and half-life for low- (92%, 73%, 52%; 10.5 y), medium- (89%, 62%, 38%; 7.3 y), and high-risk clusters (85%, 52%, 26%; 5.2 y). CONCLUSIONS: Advanced methods incorporating machine/deep learning led to a risk scoring model (including recipient, donor, and transplant factors) and a web-based clinical tool providing short- and long-term survival probabilities for recipient-donor matches. This will enable risk-based matching that could improve utilization of and benefit from a limited donor pool.

17.
J Phys Chem Lett ; 13(17): 3863-3872, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35467868

RESUMO

The impressive success of DNA sequencing using nanopores makes it possible to realize nanopore based protein sequencing. Well-controlled capture and linear movement of the protein are essential for accurate nanopore protein sequencing. Here, by taking advantage of different binding affinities of protein to two isomorphic materials, we theoretically designed a heterostructual platform for delivering the unfolded peptide to the nanopore sensing region. Due to the stronger binding between the peptide and SnS2 compared to MoS2, the peptide would adsorb to the SnS2 nanostripe and keep its threadlike conformation in the MoS2/SnS2/MoS2 heterostructure. Through switching the direction of the applied electric field in real time, the peptide was strategically driven to move along the designed path to the target nanopore. The ionic current blockades were also found to be different as the compositions of the peptide were changed, indicating the possibility for differentiating different peptides using this platform.


Assuntos
Nanoporos , DNA/química , Molibdênio/química , Peptídeos , Análise de Sequência de Proteína
18.
Front Bioeng Biotechnol ; 10: 827408, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35392407

RESUMO

Since the emergence of deep neural network (DNN), it has achieved excellent performance in various research areas. As the combination of DNN and reinforcement learning, deep reinforcement learning (DRL) becomes a new paradigm for solving differential game problems. In this study, we build up a reinforcement learning environment and apply relevant DRL methods to a specific bio-inspired differential game problem: the dog sheep game. The dog sheep game environment is set on a circle where the dog chases down the sheep attempting to escape. According to some presuppositions, we are able to acquire the kinematic pursuit and evasion strategy. Next, this study implements the value-based deep Q network (DQN) model and the deep deterministic policy gradient (DDPG) model to the dog sheep game, attempting to endow the sheep the ability to escape successfully. To enhance the performance of the DQN model, this study brought up the reward mechanism with a time-out strategy and the game environment with an attenuation mechanism of the steering angle of sheep. These modifications effectively increase the probability of escape for the sheep. Furthermore, the DDPG model is adopted due to its continuous action space. Results show the modifications of the DQN model effectively increase the escape probabilities to the same level as the DDPG model. When it comes to the learning ability under various environment difficulties, the refined DQN and the DDPG models have bigger performance enhancement over the naive evasion model in harsh environments than in loose environments.

19.
Bioengineered ; 13(4): 10111-10122, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35435117

RESUMO

Astragaloside IV (AS-IV) is an inartificial saponin separated from astragalus membranaceus, which has exhibited key anti-tumor regulation in some cancers. Circular RNAs (circRNAs) are important regulators in malignant development of gastric cancer (GC). Herein, we focused on the molecular mechanism of AS-IV with circRNA dihydrolipoamide S-succinyltransferase (circDLST) in GC. CircDLST, microRNA-489-3p (miR-489-3p), and eukaryotic translation initiation factor 4A1 (EIF4A1) levels were detected by quantitative real-time polymerase-chain reaction and western blot. Cell functions were assessed by cell counting kit-8 assay, ethynyl-2'-deoxyuridine assay, colony formation assay, and transwell assay. The interaction between miR-489-3p and circDLST or EIF4A1 was analyzed by dual-luciferase reporter assay. Xenograft tumor assay was adopted to check the role of circDLST and AS-IV in vivo. CircDLST and EIF4A1 were upregulated but miR-489-3p was downregulated in GC cells. AS-IV restrained cell proliferation and metastasis in GC cells by downregulating circDLST. CircDLST served as a miR-489-3p sponge, and miR-489-3p inhibition reversed anti-tumor function of AS-IV. EIF4A1 was a target for miR-489-3p and circDLST sponged miR-489-3p to regulate EIF4A1. AS-IV suppressed GC cell progression via circDLST-mediated downregulation of EIF4A1. Also, AS-IV recued tumor growth in vivo via targeting circDLST to regulate miR-489-3p/EIF4A1 axis. AS-IV inhibited the development of GC through circDLST/miR-489-3p/EIF4A1 axis.


Assuntos
MicroRNAs , Saponinas , Neoplasias Gástricas , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Fatores de Iniciação de Peptídeos , RNA Circular/genética , Saponinas/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Ácido Tióctico/análogos & derivados , Triterpenos
20.
Inorg Chem ; 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35477263

RESUMO

Recently, the development of porous absorbents for efficient CO2 and I2 capture has attracted considerable attention because of severe global climate change and environmental issues with the nuclear energy. Hence, a unique porous metal-organic framework (MOF), {[Co(L)]·DMF·2H2O}n (1, DMF = N,N-dimethylformamide) with uncoordinated N atoms was rationally constructed via using a heterofunctional 4,6-bis(4'-carboxyphenyl)pyrimidine (H2L) linker. Interestingly, 1 exhibits exceptional properties for I2 sorption, CO2 capture, and catalytic conversion. Particularly, I2 can be efficiently removed in both vapor and solution forms, and the adsorption amount can reach 676.25 and 345.28 mg g-1, respectively. Furthermore, complex 1 displays high adsorption capacity for CO2 (53.78 cm3 g-1, 273 K). Consequently, 1 is expected to be a promising and practical material for environmental purification due to its excellent adsorption properties.

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