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1.
J Agric Food Chem ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857358

RESUMO

Bacillus cereus (B. cereus) is a foodborne pathogen that can produce tripartite enterotoxins, which can cause a variety of diseases after infection. It is critical to rapidly and accurately detect strains with enteropathogenic potential to safeguard human health. In this study, a dual-signal visualized detection platform with fluorescence assay and paper-based lateral flow assay (LFA) based on recombinase polymerase amplification (RPA), CRISPR/Cas12a system, and self-developed CRISPR nucleic acid test strips was constructed for enterotoxigenic B. cereus. The genes that encode two tripartite enterotoxins─nheA, nheB, and nheC for nonhemolytic enterotoxin and hblA, hblC, and hblD for hemolysin BL─were utilized as detection targets. The platform was capable of detecting six enterotoxin genes at the same genomic DNA level. The limits of detection for each gene were 10-3 ng/µL in fluorescence assay and 10-4 ng/µL in LFA. Furthermore, 101-102 CFU/mL of B. cereus in pure culture was detected. Additionally, a smartphone miniprogram could assist in evaluating the results in LFA. The platform demonstrated good utility by detecting B. cereus in food samples, including milk and rice. The results indicate that our RPA-CRISPR/Cas12a dual-signal visualized detection platform can quickly and easily detect B. cereus with three-component enterotoxin-producing potentials. The whole analytic process took less than 60 min without complex operation or expensive equipment.

2.
Front Cell Infect Microbiol ; 14: 1373004, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38938880

RESUMO

In recent years, a growing body of research has confirmed that the gut microbiota plays a major role in the maintenance of human health and disease. A gut microbiota imbalance can lead to the development of many diseases, such as pregnancy complications, adverse pregnancy outcomes, polycystic ovary syndrome, endometriosis, and cancer. Short-chain fatty acids are metabolites of specific intestinal bacteria and are crucial for maintaining intestinal homeostasis and regulating metabolism and immunity. Endometriosis is the result of cell proliferation, escape from immune surveillance, and invasive metastasis. There is a strong correlation between the anti-proliferative and anti-inflammatory effects of short-chain fatty acids produced by gut microbes and the development of endometriosis. Given that the mechanism of action of gut microbiota and Short-chain fatty acids in endometriosis remain unclear, this paper aims to provide a comprehensive review of the complex interactions between intestinal flora, short-chain fatty acids and endometriosis. In addition, we explored potential microbial-based treatment strategies for endometriosis, providing new insights into the future development of diagnostic tests and prevention and treatment methods for endometriosis.


Assuntos
Endometriose , Ácidos Graxos Voláteis , Microbioma Gastrointestinal , Endometriose/metabolismo , Endometriose/microbiologia , Humanos , Feminino , Ácidos Graxos Voláteis/metabolismo , Animais , Bactérias/metabolismo , Probióticos
3.
Neurochem Res ; 49(9): 2491-2504, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38862726

RESUMO

Idebenone, an antioxidant used in treating oxidative damage-related diseases, has unclear neuroprotective mechanisms. Oxidative stress affects cell and mitochondrial membranes, altering Adp-ribosyl cyclase (CD38) and Silent message regulator 3 (SIRT3) protein expression and possibly impacting SIRT3's ability to deacetylate Tumor protein p53 (P53). This study explores the relationship between CD38, SIRT3, and P53 in H2O2-injured HT22 cells treated with Idebenone. Apoptosis was detected using flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining after determining appropriate H2O2 and Idebenone concentrations.In this study, Idebenone was found to reduce apoptosis and decrease P53 and Caspase3 expression in H2O2-injured HT22 cells by detecting apoptosis-related protein expression. Through bioinformatics methods, CD38 was identified as the target of Idebenone, and it further demonstrated that Idebenone decreased the expression of CD38 and increased the level of SIRT3. An increased NAD+/NADH ratio was detected, suggesting Idebenone induces SIRT3 expression and protects HT22 cells by decreasing apoptosis-related proteins. Knocking down SIRT3 downregulated acetylated P53 (P53Ac), indicating SIRT3's importance in P53 deacetylation.These results supported that CD38 was used as a target of Idebenone to up-regulate SIRT3 to deacetylate activated P53, thereby protecting HT22 cells from oxidative stress injury. Thus, Idebenone is a drug that may show great potential in protecting against reactive oxygen species (ROS) induced diseases such as Parkinson's disease, and Alzheimer's disease. And it might be able to compensate for some of the defects associated with CD38-related diseases.


Assuntos
ADP-Ribosil Ciclase 1 , Apoptose , Estresse Oxidativo , Sirtuína 3 , Proteína Supressora de Tumor p53 , Ubiquinona , Proteína Supressora de Tumor p53/metabolismo , Estresse Oxidativo/efeitos dos fármacos , ADP-Ribosil Ciclase 1/metabolismo , Animais , Ubiquinona/análogos & derivados , Ubiquinona/farmacologia , Camundongos , Sirtuína 3/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Peróxido de Hidrogênio/toxicidade , Antioxidantes/farmacologia , Glicoproteínas de Membrana/metabolismo , Fármacos Neuroprotetores/farmacologia
4.
Plant Dis ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568794

RESUMO

Green-stem forsythia (Forsythia viridissima), also known as golden bell, is cultivated widely in China as an early spring flowering shrub. In July 2020, yellow or white vein clearing symptoms on leaves were observed in approximate 15% golden bell plants along a landscape river in Ningbo city, Zhejiang province, China. Symptomatic leaves from six different plants were collected and pooled. Total RNA was extracted from about 200 mg pooled sample using TRIzol Reagent (Invitrogen, Carlsbad, USA) and used for high-throughput sequencing (HTS). The cDNA library was constructed using a TruSeq RNA Sample Preparation Kit (Illumina) and an Illumina NovaSeq 6000 platform was utilized to yield 150 nt paired-end reads. CLC Genomic Workbench 11 (QIAGEN) with default parameters were used for data analysis. A total of 41,604,174 paired-end reads were obtained, and 156,853 contigs (16 - 26,665 nt) were generated de novo and compared with sequences in the NCBI nt and nr database using BLASTn and BLASTx, respectively. A total of 197,277 reads were mapped to the citrus leaf blotch virus (CLBV; genus Citrivirus, family Betaflexiviridae) genome with an average coverage of 3191×. A contig of 8783 nt (excluding the poly(A) tail) was aligned to CLBV isolate Vib (accession No. OP751940) by BLASTn with the highest nt sequence identity of 99.7% and 99% query coverage, suggesting that the samples were infected with CLBV (Myung-Hwi Kim et al. 2023). No other virus was detected by this analysis. Subsequently, leaves of the six plants collected above, three plants with mild chlorotic symptoms and three plants without obvious symptoms were tested separately by RT-PCR and all were positive for CLBV. Sap from multiple symptomatic F. viridissima leaves was mechanically inoculated to Nicotiana benthamiana, N. tabacum and Datura stramonium in sextuplicate, but after two months, none of the inoculated plants had obvious symptoms and all of them tested negative for CLBV using RT-PCR. To determine the genome sequence of CLBV present in F. viridissima, a single sample from one plant was selected for genome validtion. The contig sequence was confirmed by Sanger sequencing of RT-PCR products amplified using CLBV-specific primers, and the 5' terminal sequence of the virus was determined using a commercial SUPERSWITCH RACE cDNA Synthesis Kit (Tiosbio, Beijing, China). The complete genomic sequence of CLBV isolated from F. viridissima was 8787 nts long, excluding the poly(A) tail, has the expected three predicted ORFs and was deposited in the GenBank database (accession no. OR766026). Phylogenetic analysis of different CLBV genome sequences from fruit trees and other hosts in GenBank using MEGA11 showed that the golden bell isolate was most closely related to isolate Vib (OP751940) from Viburnum lentago in South Korea, with which it was almost identical (99.7% complete nt sequence identity and >99% aa sequence identity in each of the three ORFs). Ten viruses have been previously reported from Forsythia spp. (Kaminska, M. 1985; Lee et al. 1997), but this is the first report of CLBV in this host. CLBV mainly infects citrus, kiwifruit and apple causing mosaic, chlorosis or yellow vein clearing symptoms, however, bud union disorder was observed in 'Nagami' kumquat infected by CLBV, which caused serious production losses (Cao et al. 2017; Li et al. 2018; Liu et al. 2019; Galipienso et al. 2001). Therefore, further investigation is needed to assess if F. viridissima can be an intermediate host to transfer CLBV to other crops.

5.
J Agric Food Chem ; 72(15): 8823-8830, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38578074

RESUMO

Emetic Bacillus cereus (B. cereus), which can cause emetic food poisoning and in some cases even fulminant liver failure and death, has aroused widespread concern. Herein, a universal and naked-eye diagnostic platform for emetic B. cereus based on recombinase polymerase amplification (RPA)-assisted CRISPR/Cas12a was developed by targeting the cereulide synthetase biosynthetic gene (cesB). The diagnostic platform enabled one-pot detection by adding components at the bottom and cap of the tube separately. The visual limit of detection of RPA-CRISPR/Cas12a for gDNA and cells of emetic B. cereus was 10-2 ng µL-1 and 102 CFU mL-1, respectively. Meanwhile, it maintained the same sensitivity in the rice, milk, and cooked meat samples even if the gDNA was extracted by simple boiling. The whole detection process can be finished within 40 min, and the single cell of emetic B. cereus was able to be recognized through enrichment for 2-5 h. The good specificity, high sensitivity, rapidity, and simplicity of the RPA-assisted CRISPR/Cas12a diagnostic platform made it serve as a potential tool for the on-site detection of emetic B. cereus in food matrices. In addition, the RPA-assisted CRISPR/Cas12a assay is the first application in emetic B. cereus detection.


Assuntos
Eméticos , Microbiologia de Alimentos , Recombinases/genética , Bacillus cereus/genética , Sistemas CRISPR-Cas , Sensibilidade e Especificidade , Nucleotidiltransferases/genética
6.
ACS Sens ; 9(2): 638-645, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38350035

RESUMO

A demonstration of an off-chip capacitance array sensor with a limit of detection of 1 µM trimethylamine N-oxide (TMAO) to diagnose a chronic metabolism disease in urine is presented. The improved Cole-Cole model is employed to determine the parameters of R_catalyzed, C_catalyzed, and Rp_catalyzed, enabling the prediction of the catalytic resistance of enzyme, reduction effects of the analyte, and characterize the small signal alternating current properties of ionic strength caused by catalysis. Based on the standard solutions, we investigate the effects of pixel geometry parameters, driving electrode width, and sensing electrode width on the electrical field change of the off-chip capacitance sensor; the proposed off-chip sensor with readout system-on-chip exhibits a high sensitivity of 21 analog-to-digital converter counts/µM TMAO (or 2.5 mV/µM TMAO), response time of 1 s, repetition of 98.9%, and drift over time of 0.5 mV. The proposed off-chip sensor effectively discriminates TMAO in a phosphate-buffered saline solution based on minute changes in capacitance induced by the TorA enzyme, resulting in a discernible 2.15% distinction. These measurements have been successfully corroborated using the conventional cyclic voltammetry method, demonstrating a mere 0.024% variance. The off-chip sensor is crafted with a specific focus on detecting TMAO, achieved by excluding any reduction reactions between the TMAO-specific enzyme TorA and the compounds creatine and creatinine present in urine. This deliberate omission ensures that the sensor's attention remains solely on TMAO, thereby enhancing its precision in achieving accurate and reliable TMAO detection.


Assuntos
Líquidos Corporais , Doenças Cardiovasculares , Trombose , Humanos , Metilaminas , Líquidos Corporais/metabolismo
7.
Front Microbiol ; 15: 1341179, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357344

RESUMO

The principal pathogen responsible for chronic urinary tract infections, immunocompromised hosts, and cystic fibrosis patients is Pseudomonas aeruginosa, which is difficult to eradicate. Due to the extensive use of antibiotics, multidrug-resistant P. aeruginosa has evolved, complicating clinical therapy. Therefore, a rapid and efficient approach for detecting P. aeruginosa strains and their resistance genes is necessary for early clinical diagnosis and appropriate treatment. This study combines recombinase polymerase amplification (RPA) and clustered regularly interspaced short palindromic repeats-association protein 13a (CRISPR-Cas13a) to establish a one-tube and two-step reaction systems for detecting the mexX gene in P. aeruginosa. The test times for one-tube and two-step RPA-Cas13a methods were 5 and 40 min (including a 30 min RPA amplification reaction), respectively. Both methods outperform Quantitative Real-time Polymerase Chain Reactions (qRT-PCR) and traditional PCR. The limit of detection (LoD) of P. aeruginosa genome in one-tube and two-step RPA-Cas13a is 10 aM and 1 aM, respectively. Meanwhile, the designed primers have a high specificity for P. aeruginosa mexX gene. These two methods were also verified with actual samples isolated from industrial settings and demonstrated great accuracy. Furthermore, the results of the two-step RPA-Cas13a assay could also be visualized using a commercial lateral flow dipstick with a LoD of 10 fM, which is a useful adjunt to the gold-standard qRT-PCR assay in field detection. Taken together, the procedure developed in this study using RPA and CRISPR-Cas13a provides a simple and fast way for detecting resistance genes.

8.
J Econ Entomol ; 117(2): 388-400, 2024 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-38266252

RESUMO

Artificial diets for silkworms overcome the seasonal limitations of traditional rearing methods with fresh mulberry leaves. However, the current wet artificial diets, steamed at high temperatures, are not favored by silkworms, and they are cumbersome and challenging to preserve. These conditions adversely affected the development of artificial diet-based sericulture production. In this study, we disinfected dry powder diets with radiation and added distilled water without steaming before use. Then, the nutritional value of finished diets and their impact on silkworm development was assessed. Compared with steamed diets, nonsteamed diets were more attractive to silkworms. Chemical assays showed significantly more essential nutrients for silkworms, including l-ascorbic acid, vitamin B1, vitamin B2, and urease in nonsteamed diets than in steamed diets. Feeding fifth-instar silkworm larvae with nonsteamed diets significantly improved the ammonia utilization efficiency of the diet and increased the cocoon shell rate and diet/silk protein conversion efficiency by 5.9% and 13.3%, respectively. When fed with nonsteamed diets, the abundance of aerobic microorganisms in silkworm intestines increased and the abundance of pathogenic bacteria decreased. Furthermore, the vitality of the silkworm, measured by the dead worm cocoon rate, significantly improved by 16.90%. In summary, preparing sterile wet diets without high-temperature steaming effectively improved the nutritional value of the diet and enhanced silkworm growth.


Assuntos
Bombyx , Morus , Animais , Seda/metabolismo , Dieta , Larva , Valor Nutritivo
9.
Curr Med Imaging ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38204242

RESUMO

OBJECTIVE: In this work, we have used histopathology as the gold standard for the diagnosis, calculated the sensitivity and positive predictive value (PPV) of computed tomography (CT), and analyzed the CT and clinical characteristics of pathologically proven elastofibromas. METHODS: A systematic retrospective analysis was performed on all patients with infrascapular lesions who were treated in the hospital from 2006 to 2018. CT and histopathological examinations were performed for all cases, and the CT sensitivity and PPV for the diagnosis of elastofibroma were calculated. 12 of 53 cases (20 lesions) underwent enhanced CT scan after CT plain scan, and the related clinical and CT features of elastofibromas have been discussed. RESULTS: Of the 54 patients treated during the study, CT diagnosis was consistent with histopathology in 53 cases. One was a false-positive patient. The PPV and sensitivity of the CT in the diagnosis of elastofibroma were 93.3% (95% CI 68.0%-99.8%) and 100%, respectively. The CT values of 12 patients with 20 lesions on plain and enhanced scans were statistically significant (P=0.001). The prevalence of elastofibromas in males and females was statistically significant (P=.000). There was no statistically significant difference in the incidence of left and right elastofibromas (P=0.752). There was no significant difference in the volume of left and right lesions (P=0.209) and the volume of elastofibromas between males and females (P=.474). CONCLUSION: CT is the most practical tool for the evaluation of elastofibromas in the infrascapular region.

10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1039021

RESUMO

Foods can be contaminated with foodborne pathogens through a variety of pathways, including water, air and soil. Food safety events caused by foodborne pathogens show a serious impact on human health. However, due to the diversity of foodborne pathogens and the complexity of food matrices, the rapid detection of foodborne pathogens was difficult. The conventional microbial culture and physiological and biochemical identification can hardly meet the need of rapid detection of foodborne pathogens in the field. It is necessary to develop rapid detection technologies for foodborne pathogens. Clustered regularly interspaced short palindromic repeats (CRISPR) and associated protein (Cas) are an adaptive immune systems of prokaryotes with specific recognition and cleavage of nucleic acid sequences, which shows good potential for development of nucleic acid detection and biosensing in the field. According to different forms of application, paper-based analytical devices can be categorized into test paper, lateral flow assay and microfluidic paper-based chips, etc. As a good simplicity and low-cost analytical testing tools, they show good prospects in the field of rapid testing. Therefore, the rapid and sensitive detection of foodborne pathogens can be realized by combining the efficient recognition ability of CRISPR/Cas system and the simplicity of paper-based analytical devices. In this paper, we briefly introduce an overview of the CRISPR/Cas system for nucleic acid detection, and this section focuses on an overview of the features and principles of the class 2 system, including types II, V and VI, which uses a single effector. The application of CRISPR/Cas system based test paper analysis, lateral flow assay and microfluidic paper-based chips for the detection of foodborne pathogens are highlighted in the paper, and finally the advantages, current challenges and future prospects of CRISPR/Cas system in combination with paper-based analytical devices to establish detection methods are discussed.

11.
iScience ; 26(10): 107860, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37752953

RESUMO

Hyperproteinemia is a metabolic disorder characterized by abnormally elevated plasma protein concentrations (PPC) in humans and animals. Here, a genetic silkworm model with high PPC was employed to investigate the effect of elevated PPC on female reproduction. Transcriptomic analysis revealed that high PPC induces downregulation of the ovarian development-related genes and disrupts ovarian sugar metabolism. Biochemical and endocrinal analyses revealed that high PPC increases trehalose and glucose levels in hemolymph and glycogen content in the fat body through activation of the gluconeogenic pathway and inhibition of the Insulin/Insulin-like growth factor signaling pathway-the serine/threonine kinase (IIS-AKT) pathway, thus disrupting characteristic metabolic homeostasis of sugar in the ovary. These resulted in ovarian developmental delay as well as reduced number and poor quality of eggs. Insulin supplementation effectively increased egg numbers by lowering blood sugar. These collective results provide new insights into the mechanisms by which high PPC negatively affects female reproduction and support the potential therapeutic effects of insulin.

12.
Acta Radiol ; 64(10): 2791-2801, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37545168

RESUMO

BACKGROUND: After initial treatment of prostate cancer, increases in prostate-specific antigen (PSA) levels commonly signify potential relapse or metastasis. 18F-labeled prostate-specific membrane antigen (PSMA) is considered a promising treatment due to its favorable physical properties. PURPOSE: To investigate the diagnostic value of 18F-PSMA PET/CT for the recurrence and/or metastasis of biochemical recurrence of prostate cancer (BRPca). MATERIAL AND METHODS: A comprehensive literature search was conducted in PubMed, EMBASE, Web of Science, and the Cochrane Library databases. Combined sensitivity and specificity values for the use of 18F-PSMA PET/CT in patients with BRPca were obtained. The quality of the studies was tested using the Diagnostic Accuracy Research Quality Assessment tool. Meta-analysis was performed using STATA 15 software, and heterogeneity was subsequently tested. RESULTS: A total of 16 studies (1162 patients) were enrolled and had significant heterogeneity. The pooled sensitivity, specificity, and AUC values for 18F-PSMA PET/CT in the diagnosis of prostate recurrence and/or metastasis were 0.93 (0.89-0.95), 0.94 (0.85-0.98), and 0.96 (0,94-0.98), respectively. Meta-regression analyses showed that the sources of heterogeneity did not relate to ligands, study designs, or participants. The pooled sensitivity and specificity values of 18F-DCFPyL PET/CT were 0.90 (0.85-0.94) and 0.89 (0.85-0.93), respectively. The pooled sensitivity and specificity values of 18F-PSMA-1007 PET/CT were 0.89 (0.85-0.93) and 0.93 (0.70-0.99), respectively. The per-patient pooled sensitivity and specificity values were 0.92 (0.86-0.96) and 0.83 (0.41-0.97), respectively. The per-lesion pooled sensitivity and specificity values were 0.91 (0.86-0.94) and 0.91 (0.86-0.94), respectively. CONCLUSION: According to our meta-analysis, 18F-PSMA PET/CT has the potential to be critical for the diagnosis of recurrence and/or metastasis in patients with BRPca.

13.
J Int Med Res ; 51(6): 3000605231178510, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37340717

RESUMO

OBJECTIVE: To explore the intrinsic mechanism of the mammalian target of rapamycin (mTOR) pathway activation and promotion of neuronal axon growth. METHODS: Human neuroblastoma cells, SH-SY5Y, were induced with all-trans retinoic acid (ATRA; 10 µM for three days) which differentiated the cell line into a neuronal-like state. Immunohistochemical staining was used to detect the differentiation status of the neuronal-like cells. Phosphatase and tensin homolog (PTEN) RNA interference (RNAi) experiments were performed on the differentiated cells; reverse transcription-polymerase chain reaction (RT-PCR) detected transcriptional levels of PTEN following 24 h of interference. After 36 h, western blot assay was used to detect expression levels of ribosomal protein S6 kinase (pS6k) and mTOR. To downregulate the expression of PTEN and cluster of differentiation 44 (CD44), a cell-surface glycoprotein, simultaneously, PTEN siRNA and CD44 siRNA sequences were mixed in equal proportions in co-interference experiments. RT-PCR detected the transcription level of CD44, and the relationship between the CD44 and axonal growth was observed after 48 h of interference. RESULTS: Microtubule-associated protein 2 (MAP2) expression was enhanced after three days of induction in SH-SY5Y cells. RT-PCR showed the transcription level of PTEN was significantly downregulated after 24 h of PTEN knockdown. mTOR and pS6k protein expression levels were significantly upregulated after 36 h of interference. CD44 transcription levels were upregulated after PTEN gene interference. The neurite length of the cells in the experimental interference group was significantly longer than that in the control group, and the expression level of CD44 was positively correlated with neurite growth. The neurite length of the PTEN-only interference group was significantly greater than that of the co-interference and ATRA groups. CONCLUSION: Activation of the mTOR pathway promoted neurite growth through upregulation of CD44 expression, thus promoting neuronal regeneration.


Assuntos
Neuritos , Neuroblastoma , Humanos , Regulação para Cima , Neuritos/metabolismo , Sirolimo , Neuroblastoma/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , RNA Interferente Pequeno/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Hialuronatos/genética
14.
Opt Lett ; 48(8): 2002-2005, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37058627

RESUMO

Smith-Purcell radiation (SPR) refers to the far-field, strong, spike radiation generated by the interaction of the evanescent Coulomb field of the moving charged particles and the surrounding medium. In applying SPR for particle detection and nanoscale on-chip light sources, wavelength tunability is desired. Here we report on tunable SPR achieved by moving an electron beam parallel to a two-dimensional (2D) metallic nanodisk array. By in-plane rotating the nanodisk array, the emission spectrum of the SPR splits into two peaks, with the shorter-wavelength peak blueshifted and the longer-wavelength one redshifted by increasing the tuning angle. This effect originates from the fact that the electrons fly effectively over a one-dimensional (1D) quasicrystal projected from the surrounding 2D lattice, and the wavelength of SPR is modulated by quasiperiodic characteristic lengths. The experimental data are in agreement with the simulated ones. We suggest that this tunable radiation provides free-electron-driven tunable multiple photon sources at the nanoscale.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1022981

RESUMO

Objective:To investigate the efficacy of dapagliflozin combined with tirofiban in patients with type 2 diabetes mellitus complicated with coronary heart disease.Methods:A total of 120 patients with type 2 diabetes mellitus and coronary heart disease treated in Fuyang People′s Hospital from January to August 2022 were prospectively selected as subjects. According to different treatment methods, they were divided into control group and experimental group. The control group was treated with tirofiban, and the experimental group was treated with dapagliflozin combined with tirofiban. The efficacy and safety of treatments between the two groups were compared.Results:After 3 months of treatment, fasting plasma glucose (FPG), 2 h postprandional blood glucose (2 h PG), glycated hemoglobin (HbA 1c), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), D-dimer (D-D) and fibrinogen (FIB) levels in 2 groups were decreased compared with before treatment:experimental group: (7.33 ± 1.77) mmol/L vs. (9.45 ± 2.05) mmol/L, (10.33 ± 2.07) mmol/L vs. (13.57 ± 2.88) mmol/L, (7.22 ± 1.28) % vs. (9.25 ± 1.78) %, (1.98 ± 0.29) mmol/L vs. (6.05 ± 1.24) mmol/L, (2.95 ± 0.37) mmol/L vs. (4.35 ± 0.76) mmol/L, (0.78 ± 0.23) mg/L vs. (1.85 ± 0.79) mg/L, (2.57 ± 0.37) g/L vs. (7.15 ± 1.36) g/L, control group: (8.21 ± 1.85) mmol/L vs. (9.68 ± 2.17) mmol/L, (11.78 ± 2.26) mmol/L vs. (13.89 ± 3.02) mmol/L, (8.25 ± 1.36) % vs. (9.37 ± 1.86) %, (2.77 ± 0.42) mmol/L vs. (6.08 ± 1.22) mmol/L, (3.84 ± 0.44) mmol/L vs. (4.27 ± 0.72) mmol/L, (1.34 ± 0.52) mg/L vs. (1.81 ± 0.72) mg/L, (5.25 ± 0.84 ) g/L vs. (7.11 ± 1.28) g/L, the differences were statistically significant ( P< 0.05). The levels of FPG, 2 h PG, HbA 1c, TC, LDL-C, D-D and FIB between the two groups were statistically significant ( P<0.05). High density lipoprotein cholesterol (HDL-C) level, left ventricular ejection fraction (LVEF), cardiac blood transfusion volume (CO), stroke output (SV), thrombin time (TT) and partially activated prothrombin time (APTT) were all increased: experimental group: (1.76 ± 0.30) mmol/L vs. (1.07 ± 0.28) mmol/L, (68.64 ± 12.91) % vs. (45.05 ± 12.24) %, (4.88 ± 0.91) L/min vs. (3.95 ± 1.12) L/min, (53.66 ± 5.43) ml/min vs. (43.27 ± 4.88) ml/min, (31.83 ± 4.39) s vs. (23.25 ± 3.44) s, (13.85 ± 2.17) s vs. (10.75 ± 1.56) s, control group: (1.43 ± 0.26) mmol/L vs. (1.06 ± 0.24) mmol/L, (60.37 ± 11.86) % vs. (45.42 ± 12.41) %, (4.37 ± 0.84) L/min vs. (4.17 ± 1.16) L/min, (47.86 ± 5.27) ml/min vs. (43.36 ± 4.94) ml/min, (27.24 ± 3.91) s vs. (23.78 ± 3.62) s, (12.74 ± 1.94) s vs. (10.89 ± 1.78) s, the differences were statistically significant ( P<0.05). There were significant differences in HDL-C, LVEF, CO, SV, TT and APTT between the two groups ( P<0.05). The incidence of adverse reactions in experimental group was lower than that in control group during treatment: 5.00% (3/60) vs. 16.67% (10/60), and the difference was statistically significant ( P<0.05). Conclusions:Dapagliflozin combined with tirofiban in the treatment of patients with type 2 diabetes mellitus complicated with coronary heart disease has obvious curative effect, and can improve blood glucose and blood lipid levels, coagulation function and cardiac function, with high safety.

16.
Materials (Basel) ; 15(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36556731

RESUMO

In laser powder bed fusion (L-PBF), most powders are not melted in the chamber and collected after the printing process. Powder reuse is appreciable without sacrificing the mechanical properties of target components. To understand the influences of powder reuse on mechanical performance, a nickel-based superalloy, IN738LC, was investigated. Powder morphology, microstructure and chemical compositions of virgin and reused powders were characterized. An increase in oxygen content, generally metallic oxides, was located on the surface of powders. Monotonic tensile and cyclic fatigue were tested. Negligible deterioration in strength and tensile ductility were found, while scattered fatigue performance with regard to fatigue life was shown. Deformation and fatigue crack propagation mechanisms were discussed for describing the powder degradation effects.

17.
Chemosphere ; 308(Pt 2): 136441, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36116632

RESUMO

The process and mechanism of heavy metal flocculation with extracellular polymeric substances (EPS) secreted by microorganisms, are crucial to their fate in natural environment, wastewater treatment and soil bioremediation applications. However, the structural features of EPS and the relationship between these features and the flocculation process and mechanism remain unclear. In the present study, structural features of the microbial product poly-γ-glutamic acid (γ-PGA) complexed with the heavy metal ions Pb2+ and Cu2+ were characterized and the evolution of these features was identified as having a key role in the flocculation process and mechanism. The secondary structure of the γ-PGA-Pb complex changed significantly, while that of the γ-PGA-Cu complex was only slightly altered. The significant structural change in γ-PGA-Pb was found to be responsible for the combination of residual COOH and Pb2+, promoting the bridging of inter-colloids and faster growth of hydrodynamic diameter. If the conformation changed sufficiently, such as with the γ-PGA-Pb complex in the pH range 4.6-6.2, pH had no impact on the conversion ratio. The unchanged structure of γ-PGA-Cu prevented the flocculation process, although the coordination mode of γ-PGA-Cu resulted in a higher biosorption capacity. This in-depth molecular-level study provides insight into the γ-PGA flocculation mechanism, promoting the use of γ-PGA and γ-PGA producing microorganisms for application in various remediation strategies.


Assuntos
Ácido Glutâmico , Metais Pesados , Coloides , Floculação , Íons , Chumbo , Metais Pesados/análise , Ácido Poliglutâmico/análogos & derivados , Solo
18.
Phys Rev Lett ; 129(2): 023601, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35867443

RESUMO

Photonic quantum information processing relies on operating the quantum state of photons, which usually involves bulky optical components unfavorable for system miniaturization and integration. Here, we report on the transformation and distribution of polarization-entangled photon pairs with multichannel dielectric metasurfaces. The entangled photon pairs interact with metasurface building blocks, where the geometrical-scaling-induced phase gradients are imposed, and are transformed into two-photon entangled states with the desired polarization. Two metasurfaces, each simultaneously distributing polarization-entangled photons to spatially separated multiple channels M (N), may accomplish M×N channels of entanglement distribution and transformation. Experimentally we demonstrate 2×2 and 4×4 distributed entanglement states, including Bell states and superposition of Bell states, with high fidelity and strong polarization correlation. We expect this approach paves the way for future integration of quantum information networks.

19.
Opt Express ; 30(9): 14839-14850, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473219

RESUMO

Topological photonics offers the possibility of robust transport and efficiency enhancement of information processing. Terahertz (THz) devices, such as waveguides and beam splitters, are prone to reflection loss owing to their sensitivity to defects and lack of robustness against sharp corners. Thus, it is a challenge to reduce backscattering loss at THz frequencies. In this work, we constructed THz photonic topological insulators and experimentally demonstrated robust, topologically protected valley transport in THz photonic crystals. The THz valley photonic crystal (VPC) was composed of metallic cylinders situated in a triangular lattice. By tuning the relevant location of metallic cylinders in the unit cell, mirror symmetry was broken, and the degenerated states were lifted at the K and K' valleys in the band structure. Consequently, a bandgap of THz VPC was opened, and a nontrivial band structure was created. Based on the calculated band structure, THz field distributions, and valley Berry curvature, we verified the topological phase transition in such type of THz photonic crystals. Further, we showed the emergence of valley-polarized topological edge states between the topologically distinct VPCs. The angle-resolved transmittance measurements identified the bulk bandgap in the band structure of the VPC. The measured time-domain spectra demonstrated the topological transport of valley edge states between distinct VPCs and their robustness against bending and defects. Furthermore, experiments conducted on a topological multi-channel intersectional device revealed the valley-polarized characteristic of the topological edge states. This work provides a unique approach to reduce backscattering loss at the THz regime. It also demonstrates potential high-efficiency THz functional devices such as topologically protected beam splitters, low-loss waveguides, and robust delay lines.

20.
Zool Res ; 43(3): 301-318, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35312240

RESUMO

Hyperproteinemia is a metabolic disorder associated with increased plasma protein concentration (PPC) and is often clinically complicated by malignant diseases or severe infections. At present, however, research on the molecular mechanism underlying high PPC (HPPC) is scant. Here, an animal model of primary hyperproteinemia was constructed in an invertebrate ( Bombyx mori) to investigate the effects of HPPC on circulating blood cells. Results showed that HPPC affected blood cell homeostasis, leading to increased reactive oxygen species levels, and induced programmed cell death dependent on the endoplasmic reticulum-calcium ion signaling pathway. HPPC induced the proliferation of blood cells, mainly granulocytes, by activating the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway. Supplementation with the endocrine hormone active substance 20E significantly reduced the impact of HPPC on blood cell homeostasis. Thus, we identified a novel signaling pathway by which HPPC affects blood cell homeostasis, which differs from hyperglycemia, hyperlipidemia, and hypercholesterolemia. In addition, we showed that down-regulation of gene expression of the hematopoietic factor Gcm could be used as a potential early detection indicator for hyperproteinemia.


Assuntos
Janus Quinases , Fatores de Transcrição STAT , Animais , Células Sanguíneas/metabolismo , Modelos Animais de Doenças , Homeostase , Janus Quinases/genética , Janus Quinases/metabolismo , Fatores de Transcrição STAT/genética , Fatores de Transcrição STAT/metabolismo
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