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1.
Small ; : e2402076, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38757424

RESUMO

High-rate lithium/sodium ion batteries or capacitors are the most promising functional units to achieve fast energy storage that highly depends on charge host materials. Host materials with lamellar structures are a good choice for hybrid charge storage hosts (capacitor or redox type). Emerging layered transition metal carbo-chalcogenides (TMCC) with homogeneous sulfur termination are especially attractive for charge storage. Using density functional theory calculations, six of 30 potential TMCC are screened to be stable, metallic, anisotropic in electronic conduction and mechanical properties due to the lamellar structures. Raman, infrared active modes and frequencies of the six TMCC are well assigned. Interlayer coupling, especially binding energies predict that the bulk layered materials can be easily exfoliated into 2D monolayers. Moreover, Ti2S2C, Zr2S2C are identified as the most gifted Li+/Na+ anode materials with relatively high capacities, moderate volume expansion, relatively low Li+/Na+ migration barriers for batteries or ion-hybrid capacitors. This work provides a foundation for rational materials design, synthesis, and identification of the emerging 2D family of TMCC.

2.
J Med Internet Res ; 26: e50355, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088814

RESUMO

Rapid global population growth and urbanization have heightened the demand for emergency medical rescue, with helicopter medical rescue emerging as an effective solution. The advent of 5G communication technology, characterized by large bandwidth, low latency, and high reliability, offers substantial promise in enhancing the efficiency and quality of helicopter rescue operations. However, the full integration of 5G technology into helicopter emergency medical services is still in its nascent stages and requires further development. In this viewpoint, we present our experience from the Shenzhen University General Hospital of the application of 5G low-altitude network communication technology, body area network disease sensing technology, and 5G air-ground collaborative rapid diagnosis and treatment technology in aeromedical rescue. We consider that the 5G air-to-ground collaborative rapid diagnosis and treatment technology enables high-quality remote consultation, enhancing emergency medical rescue and providing strong support for future rescue operations.


Assuntos
Resgate Aéreo , Resgate Aéreo/estatística & dados numéricos , Humanos , Serviços Médicos de Emergência/métodos , Trabalho de Resgate/métodos , Aeronaves
3.
J Adv Nurs ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605460

RESUMO

AIMS: Early identification and intervention of the frailty of the elderly will help lighten the burden of social medical care and improve the quality of life of the elderly. Therefore, we used machine learning (ML) algorithm to develop models to predict frailty risk in the elderly. DESIGN: A prospective cohort study. METHODS: We collected data on 6997 elderly people from Chinese Longitudinal Healthy Longevity Study wave 6-7 surveys (2011-2012, 2014). After the baseline survey in 1998 (wave 1), the project conducted follow-up surveys (wave 2-8) in 2000-2018. The osteoporotic fractures index was used to assess frailty. Four ML algorithms (random forest [RF], support vector machine, XGBoost and logistic regression [LR]) were used to develop models to identify the risk factors of frailty and predict the risk of frailty. Different ML models were used for the prediction of frailty risk in the elderly and frailty risk was trained on a cohort of 4385 elderly people with frailty (split into a training cohort [75%] and internal validation cohort [25%]). The best-performing model for each study outcome was tested in an external validation cohort of 6997 elderly people with frailty pooled from the surveys (wave 6-7). Model performance was assessed by receiver operating curve and F2-score. RESULTS: Among the four ML models, the F2-score values were similar (0.91 vs. 0.91 vs. 0.88 vs. 0.90), and the area under the curve (AUC) values of RF model was the highest (0.75), followed by LR model (0.74). In the final two models, the AUC values of RF and LR model were similar (0.77 vs. 0.76) and their accuracy was identical (87.4% vs. 87.4%). CONCLUSION: Our study developed a preliminary prediction model based on two different ML approaches to help predict frailty risk in the elderly. IMPACT: The presented models from this study can be used to inform healthcare providers to predict the frailty probability among older adults and maybe help guide the development of effective frailty risk management interventions. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: Detecting frailty at an early stage and implementing timely targeted interventions may help to improve the allocation of health care resources and to reduce frailty-related burden. Identifying risk factors for frailty could be beneficial to provide tailored and personalized care intervention for older adults to more accurately prevent or improve their frail conditions so as to improve their quality of life. REPORTING METHOD: The study has adhered to STROBE guidelines. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

4.
Sensors (Basel) ; 24(15)2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39123944

RESUMO

GNSS spoofing has become a significant security vulnerability threatening remote sensing systems. Hardware fingerprint-based GNSS receiver identification is one of the solutions to address this security issue. However, existing research has not provided a solution for distinguishing GNSS receivers of the same specification. This paper first theoretically proves that the CSACs (Chip-Scale Atomic Clocks) used in GNSS receivers have unique hardware noise and then proposes a fingerprinting scheme based on this hardware noise. Experiments based on the neural network method demonstrate that this fingerprint achieved an identification accuracy of 94.60% for commercial GNSS receivers of the same specification and performed excellently in anomaly detection, confirming the robustness of the fingerprinting method. This method shows a new real-time GNSS security monitoring method based on CSACs and can be easily used with any commercial GNSS receivers.

5.
J Org Chem ; 88(1): 513-524, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36545950

RESUMO

Herein, the efficient photoredox/nickel dual-catalyzed cyanoalkylation reaction of enamides is illustrated. A wide scope of enamides and cycloketone oxime esters was well-tolerated, affording the synthetically versatile and geometrically defined ß-cyanoalkylated enamide scaffolds. The synthetic practicality of this protocol was revealed by gram-scale reactions, further transformations of enamides, and late-stage modifications of biologically active molecules.


Assuntos
Amidas , Níquel , Estrutura Molecular , Catálise
6.
Surg Endosc ; 37(5): 3380-3397, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36627536

RESUMO

BACKGROUND: Pancreaticoduodenectomy is the first choice surgical intervention for the radical treatment of pancreatic tumors. However, an anastomotic fistula is a common complication after pancreaticoduodenectomy with a high mortality rate. With the development of minimally invasive surgery, open pancreaticoduodenectomy (OPD), laparoscopic pancreaticoduodenectomy (LPD), and robotic pancreaticoduodenectomy (RPD) are gaining interest. But the impact of these surgical methods on the risk of anastomosis has not been confirmed. Therefore, we aimed to integrate relevant clinical studies and explore the effects of these three surgical methods on the occurrence of anastomotic fistula after pancreaticoduodenectomy. METHODS: A systematic literature search was conducted for studies reporting the RPD, LPD, and OPD. Network meta-analysis of postoperative anastomotic fistula (Pancreatic fistula, biliary leakage, gastrointestinal fistula) was performed. RESULTS: Sixty-five studies including 10,026 patients were included in the network meta-analysis. The rank of risk probability of pancreatic fistula for RPD (0.00) was better than LPD (0.37) and OPD (0.62). Thus, the analysis suggests the rank of risk of the postoperative pancreatic fistula for RPD, LPD, and OPD. The rank of risk probability for biliary leakage was similar for RPD (0.15) and LPD (0.15), and both were better than OPD (0.68). CONCLUSIONS: This network meta-analysis provided ranking for three different types of pancreaticoduodenectomy. The RPD and LPD can effectively improve the quality of surgery and are safe as well as feasible for OPD.


Assuntos
Laparoscopia , Neoplasias Pancreáticas , Procedimentos Cirúrgicos Robóticos , Humanos , Pancreaticoduodenectomia/efeitos adversos , Pancreaticoduodenectomia/métodos , Fístula Pancreática/etiologia , Fístula Pancreática/complicações , Metanálise em Rede , Pancreatectomia/efeitos adversos , Neoplasias Pancreáticas/patologia , Anastomose Cirúrgica/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Laparoscopia/métodos , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Tempo de Internação
7.
Nucleic Acids Res ; 49(5): 2946-2958, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33577684

RESUMO

RBM45 is an RNA-binding protein involved in neural development, whose aggregation is associated with neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS) and frontotemporal lobar dementia (FTLD). However, the mechanisms of RNA-binding and aggregation of RBM45 remain unelucidated. Here, we report the crystal structure of the N-terminal tandem RRM domains of human RBM45 in complex with single-stranded DNA (ssDNA). Our structural and biochemical results revealed that both the RRM1 and RRM2 of RBM45 recognized the GAC sequence of RNA/ssDNA. Two aromatic residues and an arginine residue in each RRM were critical for RNA-binding, and the interdomain linker was also involved in RNA-binding. Two RRMs formed a pair of antiparallel RNA-binding sites, indicating that the N-terminal tandem RRM domains of RBM45 bound separate GAC motifs in one RNA strand or GAC motifs in different RNA strands. Our findings will be helpful in the identification of physiologic targets of RBM45 and provide evidence for understanding the physiologic and pathologic functions of RBM45.


Assuntos
Proteínas do Tecido Nervoso/química , Proteínas de Ligação a RNA/química , RNA/química , Cristalografia por Raios X , DNA de Cadeia Simples/química , Humanos , Modelos Moleculares , Proteínas do Tecido Nervoso/metabolismo , Motivos de Nucleotídeos , Ligação Proteica , RNA/metabolismo , Motivo de Reconhecimento de RNA , Proteínas de Ligação a RNA/metabolismo
8.
Gastrointest Endosc ; 95(4): 599-609.e7, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34979114

RESUMO

BACKGROUND AND AIMS: This study aimed to evaluate the accuracy and effectiveness of the convolutional neural network (CNN) in diagnosing gastric cancer and predicting the invasion depth of gastric cancer and to compare the performance of the CNN with that of endoscopists. METHODS: PubMed, Embase, Web of Science, and gray literature were searched until July 23, 2021 for studies that assessed the diagnostic accuracy of CNN-assisted examinations for gastric cancer or the invasion depth of gastric cancer. Studies meeting inclusion criteria were included in the systematic review and meta-analysis. RESULTS: Seventeen studies comprising 51,446 images and 174 videos of 5539 patients were included. The pooled sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-), and area under the curve (AUC) of the CNN for diagnosing gastric cancer were 89% (95% confidence interval [CI], 85-93), 93% (95% CI, 88-97), 13.4 (95% CI, 7.3-25.5), .11 (95% CI, .07-.17), and .94 (95% CI, .91-.98), respectively. The performance of the CNN in diagnosing gastric cancer was not significantly different from that of expert endoscopists (.95 vs .90, P > .05) and was better than that of overall endoscopists (experts and nonexperts) (.95 vs .87, P < .05). The pooled sensitivity, specificity, LR+, LR-, and AUC of the CNN for predicting the invasion depth of gastric cancer were 82% (95% CI, 78-85), 90% (95% CI, 82-95), 8.4 (95% CI, 4.2-16.8), .20 (95% CI, .16-.26), and .90 (95% CI, .87-.93), respectively. CONCLUSIONS: The CNN is highly accurate in diagnosing gastric cancer and predicting the invasion depth of gastric cancer. The performance of the CNN in diagnosing gastric cancer is not significantly different from that of expert endoscopists. Studies of the real-time performance of the CNN for gastric cancer diagnosis are needed to confirm these findings.


Assuntos
Neoplasias Gástricas , Detecção Precoce de Câncer/métodos , Endoscopia , Humanos , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Neoplasias Gástricas/diagnóstico por imagem
9.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(4): 413-416, 2022 Apr 10.
Artigo em Zh | MEDLINE | ID: mdl-35446978

RESUMO

OBJECTIVE: To analyze the clinical and genetic features of a patient with mevalonate kinase deficiency (MKD). METHODS: Whole exome sequencing was carried out for the proband. Candidate variant was verified by Sanger sequencing. RESULTS: The proband was found to harbor compound heterozygous variants of the MVK gene, including a c.248C>T (p.Phe83Cys) variant derived from his father and a c.971C>T (p.Ala324Val) variant from his mother. Based on the guidelines of the American College of Medical Genetics and Genomics, both variations were predicted to be likely pathogenic (PM1 + PM2 + PM3 + PP3). CONCLUSION: The compound heterozygous variants of the MVK gene probably underlay the MKD in the proband. Above findings have enriched the mutational spectrum of the MVK gene.


Assuntos
Deficiência de Mevalonato Quinase , Criança , Genômica , Humanos , Imunoglobulina D/genética , Deficiência de Mevalonato Quinase/genética , Mutação , Sequenciamento do Exoma
10.
Entropy (Basel) ; 24(10)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37420487

RESUMO

The quantum computer has been claimed to show more quantum advantage than the classical computer in solving some specific problems. Many companies and research institutes try to develop quantum computers with different physical implementations. Currently, most people only focus on the number of qubits in a quantum computer and consider it as a standard to evaluate the performance of the quantum computer intuitively. However, it is quite misleading in most times, especially for investors or governments. This is because the quantum computer works in a quite different way than classical computers. Thus, quantum benchmarking is of great importance. Currently, many quantum benchmarks are proposed from different aspects. In this paper, we review the existing performance benchmarking protocols, models, and metrics. We classify the benchmarking techniques into three categories: physical benchmarking, aggregative benchmarking, and application-level benchmarking. We also discuss the future trend for quantum computer's benchmarking and propose setting up the QTOP100.

11.
Biochem Biophys Res Commun ; 566: 170-176, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34129964

RESUMO

Akkermansia muciniphila is a symbiotic intestinal bacterium with a high medicinal value. Amuc_1100 is the outer membrane protein of A. muciniphila and plays an important role in the interaction between A. muciniphila and its host. The objective of this study was to evaluate the antidepressant activity of Amuc_1100 in a chronic unpredictable mild stress (CUMS) model. Amuc_1100 intervention ameliorated CUMS-induced depression-like behavior and CUMS-induced down-regulation of serotonin (5-hydroxytryptamine, or simply, 5-HT) in the serum and colon of mice. Microbial analysis of mouse feces showed that Amuc_1100 could improve the gut microbiota dysregulation induced by CUMS. In addition, Amuc_1100 intervention could also improve the down-regulation of brain-derived neurotrophic factor (BDNF) and inflammation in the hippocampus induced by CUMS. These results suggest that Amuc_1100 has a good antidepressant effect, and the mechanism may be related to the improvement of gut microbiota, the up-regulation of the BDNF level, and the inhibition of the neuroinflammatory response.


Assuntos
Proteínas de Bactérias/metabolismo , Depressão/microbiologia , Microbioma Gastrointestinal , Camundongos/microbiologia , Akkermansia/fisiologia , Animais , Antidepressivos/metabolismo , Antidepressivos/uso terapêutico , Proteínas de Bactérias/uso terapêutico , Depressão/etiologia , Depressão/metabolismo , Modelos Animais de Doenças , Masculino , Camundongos/metabolismo , Camundongos Endogâmicos C57BL , Estresse Psicológico/complicações
12.
Biochem Biophys Res Commun ; 547: 59-64, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33592380

RESUMO

Akkermansia muciniphila is a kind of beneficial microorganism colonized in the human gut. A. muciniphila is closely related to human intestinal health and has a good effect on diseases related to intestinal metabolism. The proteins encoded by the Amuc_1098-Amuc_1102 gene cluster, which are related to the formation and assembly of the pilus, are highly expressed in the membrane protein components of A. muciniphila. In this paper, we report the crystal structure of Amuc_1102 at a resolution of 1.75 Å, which adopts an immunoglobulin (Ig)-like fold. Amuc_1102 shares a similar fold to three archaeal proteins related to type IV pilus (T4P)-like structure, Pilin, FlaF, and FlaG, indicating a similar function. Amuc_1102 exists as a trimer both in the crystal structure and in solution, which differs from the assemblies of Pilin, FlaF, and FlaG. This study provides a structural basis for the elucidation of the T4P formation of A. muciniphila.


Assuntos
Archaea/metabolismo , Proteínas de Bactérias/química , Cristalografia por Raios X/métodos , Fímbrias Bacterianas/química , Imunoglobulinas/química , Proteínas de Membrana/química , Akkermansia/química , Akkermansia/metabolismo , Archaea/química , Proteínas de Bactérias/metabolismo , Fímbrias Bacterianas/metabolismo , Humanos , Imunoglobulinas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação
13.
Biochem J ; 477(1): 161-172, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31860021

RESUMO

RNA-binding protein RBM38 was reported to bind the mRNA of several p53-related genes through its RRM domain and to up-regulate or down-regulate protein translation by increasing mRNA stability or recruitment of other effector proteins. The recognition mechanism, however, for RNA-binding of RBM38 remains unclear. Here, we report the crystal structure of the RRM domain of human RBM38 in complex with a single-stranded RNA. Our structural and biological results revealed that RBM38 recognizes G(U/C/A)GUG sequence single-stranded RNA in a sequence-specific and structure-specific manner. Two phenylalanine stacked with bases of RNA were crucial for RNA binding, and a series of hydrogen bonds between the base atoms of RNA and main-chain or side-chain atoms of RBM38 determine the sequence-specific recognition. Our results revealed the RNA-recognition mechanism of human RBM38 and provided structural information for understanding the RNA-binding property of RBM38.


Assuntos
RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Sítios de Ligação , Humanos , Ligação Proteica , Domínios Proteicos
14.
J Struct Biol ; 212(1): 107593, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32736072

RESUMO

Akkermansia muciniphila is a beneficial microorganism colonized in the human gut that can reverse many intestinal metabolic-related diseases. Amuc_1100 is an outer-membrane protein of A. muciniphila. Oral administration of Amuc_1100 can reduce fat mass development, insulin resistance, and dyslipidemia in mice and activated the toll-like receptor 2 (TLR2) to regulate the immune response of the host, but the molecular mechanism remains unclear. Here we report the crystal structure of the extramembranous domain of Amuc_1100, which consists of a four-stranded antiparallel ß-sheet and four α-helices. Two C-terminal helices and the four-stranded antiparallel ß-sheet formed two "αßß" motifs and constituted the core domain, which shared a similar fold with type IV pili and type II Secretion system protein. Although the full-length of the extramembranous domain of Amuc_1100 existed as a monomer in solution, they formed trimer in the crystal. Elimination of the N-terminal coiled-coil helix α1 led to dimerization of Amuc_1100 both in solution and in crystal, indicating that the oligomeric state of Amuc_1100 was variable and could be influenced by α1. In addition, we identified that Amuc_1100 could directly bind human TLR2 (hTRL2) in vitro, suggesting that Amuc_1100 may serve as a new ligand for hTLR2. Dimerization of Amuc_1100 improved its hTLR2-binding affinity, suggesting that the α1-truncated Amuc_1100 could be a beneficial candidate for the development of A. muciniphila related drugs.


Assuntos
Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/metabolismo , Akkermansia/metabolismo , Sistemas de Secreção Bacterianos/metabolismo , Humanos , Conformação Proteica em alfa-Hélice/fisiologia , Conformação Proteica em Folha beta/fisiologia , Domínios Proteicos/fisiologia , Receptor 2 Toll-Like/metabolismo
15.
Sensors (Basel) ; 20(17)2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32867180

RESUMO

The lack of a universal simulation method for triboelectric nanogenerator (TENG) makes the device design and optimization difficult before experiment, which protracts the research and development process and hinders the landing of practical TENG applications. The existing electrostatic induction models for TENGs have limitations in simulating TENGs with complex geometries and their dynamic behaviors under practical movements due to the topology change issues. Here, a dynamic finite element method (FEM) model is proposed. The introduction of air buffer layers and the moving mesh method eliminates the topology change issues during practical movement and allows simulation of dynamic and time-varying behaviors of TENGs with complex 2D/3D geometries. Systematic investigations are carried out to optimize the air buffer thickness and mesh densities, and the optimized results show excellent consistency with the experimental data and results based on other existing methods. It also shows that a 3D disk-type rotating TENG can be simulated using the model, clearly demonstrating the capability and superiority of the dynamic FEM model. Moreover, the dynamic FEM model is used to optimize the shape of the tribo-material, which is used as a preliminary example to demonstrate the possibility of designing a TENG-based sensor.

16.
Biochem Biophys Res Commun ; 520(2): 347-352, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31604522

RESUMO

Typical 2-cysteine peroxiredoxins (2-Cys Prxs) are critical peroxidase sensors and could be deactivated by the hyperoxidation under oxidative stress. In plants, 2-Cys Prxs present at a high level in chloroplasts and are repaired by Sulfiredoxin. Whereas many studies have explored the mechanism of Sulfiredoxin from Homo sapiens (HsSrx), the molecular mechanism of Sulfiredoxin in plants with unique photosynthesis remains unclear. Here we report the crystal structure of Sulfiredoxin from Arabidopsis thaliana (AtSrx), which displayed a typical ParB/Srx fold with an ATP bound at a conservative nucleotide binding motif GCHR. Both the ADP binding pocket and the putative AtSrx-AtPrxA interaction surface of AtSrx are more positively charged comparing to HsSrx, suggesting a robust mechanism of AtSrx. These features illustrate the unique mechanisms of AtSrx, which are vital for figure out the strategies of plants to cope with oxidation stress.


Assuntos
Proteínas de Arabidopsis/química , Arabidopsis/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/química , Difosfato de Adenosina/química , Difosfato de Adenosina/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arginina/química , Arginina/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Modelos Moleculares , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Peroxirredoxinas/metabolismo , Conformação Proteica , Dobramento de Proteína
17.
Biochem Biophys Res Commun ; 511(4): 833-839, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30846208

RESUMO

ß-N-acetylhexosaminidases from Akkermansia muciniphila was reported to perform the crystal structure with GlcNAc complex, which proved to be the substrate of Am2301. Domain II of Am2301 is consisted of amino acid residues 111-489 and is folded as a (ß/α)8 barrel with the active site combined of the glycosyl hydrolases. Crystallographic evidence showed that Asp-278 and Glu-279 could be the catalytic site and Tyr-373 may plays a role on binding the substrate. Moreover, Am2301 prefers to bind Zn ion, which similar to other GH 20 family. Enzyme activity and kinetic parameters of wild-type Am2301 and mutants proved that Asp-278 and Glu-279 are the catalytic sites and they play a critical role on the catalytic process. Overall, our results demonstrate that Am2301 and its complex with GlcNAC provide obvious structural evidence for substrate-assisted catalysis. Obviously, this expands our understanding on the mode of substrate-assisted reaction for this enzyme family in Akkermansia muciniphila.


Assuntos
Acetilglucosamina/metabolismo , Proteínas de Bactérias/metabolismo , Verrucomicrobia/metabolismo , beta-N-Acetil-Hexosaminidases/metabolismo , Proteínas de Bactérias/química , Domínio Catalítico , Cristalografia por Raios X , Cinética , Modelos Moleculares , Especificidade por Substrato , Verrucomicrobia/química , Verrucomicrobia/enzimologia , beta-N-Acetil-Hexosaminidases/química
18.
Cancer Cell Int ; 18: 39, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29568234

RESUMO

BACKGROUND: MicroRNA-21 (miR-21) was previously reported being dysregulated in many kinds of cancer including esophageal squamous cell carcinoma (ESCC). In the present study, we aimed to investigate the role of miR-21 in ESCC, especially in its effects on radiation-sensitivity of ESCC. METHODS: Expression of miR-21 was detected in 63 pairs ESCC tumor and adjacent non-tumoral tissues using qRT-PCR, correlation between miR-21 and clinicopathological feature of ESCC was analyzed. The role of miR-21 in the proliferation, cell cycle and apoptosis of ESCC cells during irradiation were studied. RESULTS: MicroRNA-21 expression was significantly increased in ESCC tumor tissues. Expression of miR-21 was positively associated with advanced clinical stage. Under irradiation, overexpression of miR-21 increased cell proliferation and cells in S phase, and inhibited cell apoptosis of ESCC cells. In contrast, knockdown of miR-21 had an opposite effect. CONCLUSIONS: Downregulation of miR-21 inhibited the radiation-resistance of ESCC, whereas overexpression of miR-21 increased the radiation-resistance. MiR-21 is a potential novel target for developing specific treatment interventions in ESCC in future.

19.
Sensors (Basel) ; 18(12)2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30572575

RESUMO

In recent years, the Wireless Body Area Network (WBAN) concept has attracted significant academic and industrial attention. WBAN specifies a network dedicated to collecting personal biomedical data from advanced sensors that are then used for health and lifestyle purposes. In 2012, the 802.15.6 WBAN standard was released by the Institute of Electrical and Electronics Engineers (IEEE), which regulates and specifies the configurations of WBAN. Compared to the prevailing wireless communication technologies such as Bluetooth and ZigBee, the WBAN standard has the advantages of ultra-low power consumption, high reliability, and high-security protection while transmitting sensitive personal data. Based on the standard specification, several implementations have been published. However, in terms of evaluation, different designs were implemented in proprietary evaluation environments, which may lead to unfair comparison. In this paper, a Software-Defined Radio (SDR) evaluation platform for WBAN systems is proposed to evaluate the RF channel specified in the IEEE 802.15.6 standard. A narrowband communication protocol demonstration with a security scheme in WBAN has been performed to successfully validate the design in the proposed evaluation platform.


Assuntos
Técnicas Biossensoriais , Monitorização Fisiológica , Software , Dispositivos Eletrônicos Vestíveis , Redes de Comunicação de Computadores , Corpo Humano , Humanos , Tecnologia sem Fio
20.
Zhongguo Dang Dai Er Ke Za Zhi ; 20(4): 285-289, 2018 Apr.
Artigo em Zh | MEDLINE | ID: mdl-29658452

RESUMO

This research investigated the clinical features of immunodeficiency disease and the features of the mutation of its pathogenic genes. All 7 patients were boys aged 5 months to 4 years and 6 months and had a history of recurrent respiratory infection and pneumonia, low levels of IgM and IgG, and abnormal absolute values or percentages of lymphocyte subsets. High-throughput sequencing showed c.1684C>T mutations in the BTK gene in patient 1 and IVS8+2T>C splice site mutations in the BTK gene in patient 2. Both of these mutations came from their mothers. Patients 3, 4, and 5 had mutations in the IL2RG gene, i.e., c.298C>T, IVS3-2A>G, and c.164T>A, among which c.164T>A mutations had not been reported. Patient 6 had c.204C>G mutations in the RAG2 gene. Patient 7 had complex heterozygous mutations of c.913C>T and c.824G>A in the RAG2 gene, which came from his father and mother, respectively. Patients with immunodeficiency disease have abnormal immunological indices, and high-throughput sequencing helps to make a definite diagnosis.


Assuntos
Agamaglobulinemia/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Síndromes de Imunodeficiência/genética , Mutação , Tirosina Quinase da Agamaglobulinemia , Pré-Escolar , Biologia Computacional , Proteínas de Ligação a DNA/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Síndromes de Imunodeficiência/terapia , Lactente , Subunidade gama Comum de Receptores de Interleucina/genética , Masculino , Proteínas Nucleares/genética , Proteínas Tirosina Quinases/genética
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