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1.
ACS Appl Mater Interfaces ; 13(33): 39066-39075, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34387079

RESUMO

A controlled release formulation based on silica microcapsules is an ideal selection to improve both the effective utilization and duration of pesticides to decrease ecological damage. Herein, a simple and green method for preparing double-shelled microcapsules was developed using a newly prepared quaternary ammonium ionic liquid (IL) as the functional additive to entrap avermectin (Ave) in mesoporous silica nanospheres (MSNs) and tannic acid-Cu (TA-Cu) complex as the sealing agent to form the core-shell structure (Ave-IL@MSN@TA-Cu). The obtained microcapsules with an average size of 538 nm had pH-responsive release property and good stability in soil. The half-life of microcapsules (34.66 days) was 3 times that of Ave emulsifiable concentrate (EC) (11.55 days) in a test soil, which illustrated that microcapsules could protect Ave from rapid degradation by microorganisms by releasing TA, copper, and quaternary ammonium in the soil. Ave-IL@MSN@TA-Cu microcapsules had better nematicidal activity and antibacterial activity than Ave EC due to the synergistic effect of Ave, IL, and copper incorporated in the microcapsules. Pot experiments showed that the control efficacy of microcapsules was 87.10% against Meloidogyne incognita, which is better than that of Ave EC (41.94%) at the concentration of 1.0 mg/plant by the root-irrigation method after 60 days of treatment owing to the extended duration of Ave in microcapsules. The simple and green method for the preparation of double-shelled microcapsules based on natural quaternary ammonium IL would have tremendous potential for the extensive development of controlled release pesticide formulations.


Assuntos
Cápsulas/química , Preparações de Ação Retardada/química , Controle de Pragas/métodos , Praguicidas/química , Dióxido de Silício/química , Tylenchoidea/efeitos dos fármacos , Animais , Complexos de Coordenação/química , Cobre/química , Preparações de Ação Retardada/farmacologia , Composição de Medicamentos , Liberação Controlada de Fármacos , Química Verde , Concentração de Íons de Hidrogênio , Líquidos Iônicos/química , Ivermectina/análogos & derivados , Ivermectina/química , Ivermectina/farmacologia , Praguicidas/farmacologia , Porosidade , Compostos de Amônio Quaternário/química , Solubilidade , Taninos/química , Fatores de Tempo
2.
J Agric Food Chem ; 69(23): 6485-6494, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34077226

RESUMO

Silver nanoparticles (AgNPs) have remarkable and broad-spectrum antibacterial activities against Gram-positive (G+) and Gram-negative bacteria (G-). However, the negative surface potential of AgNPs limits their antibacterial activities due to the electrostatic repulsion with the negatively charged bacterial cell membrane. To address the limitation, AgNPs were loaded in the mesoporous silica nanoparticles by preparing silver core-mesoporous silica shell nanocapsules (Ag@MSNs), and then, a cationic antibacterial polymer, quaternary ammonium polyethyleneimine (QPEI), was used to modify Ag@MSNs for improving their surface potential and antibacterial activities. The results showed that the obtained Ag@MSN-QPEI exhibited a high positive surface potential (+39.6 mV) and a strong electrostatic attraction with Pseudomonas syringae pv. lachrymans cells in coculture, resulting in an excellent bacterial cell-targeting effect. At the same concentration, Ag@MSN-QPEI exhibited less silver content (reducing the silver content of Ag@MSNs by 19%), higher antibacterial activities, and longer effective duration against Clavibacter michiganensis subsp. michiganensis (G+) and P. syringae pv. lachrymans (G-) than Ag@MSNs and QPEI alone. The excellent bacterial cell-targeting effect and synergistic antibacterial action combined with QPEI accounted for the significantly enhanced antibacterial activities of Ag@MSN-QPEI. Therefore, using a cationic antibacterial polymer to confer the bacterial cell-targeting effect and synergistic antibacterial action would be extended to other antimicrobial materials.


Assuntos
Compostos de Amônio , Nanopartículas Metálicas , Nanocápsulas , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Polietilenoimina , Dióxido de Silício , Prata/farmacologia
3.
Sci Total Environ ; 787: 147422, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33991920

RESUMO

In this work, a pH-responsive pesticide delivery system using mesoporous silica nanoparticles (MSNs) as the porous carriers and coordination complexes of Cu ions and tannic acid (TA-Cu) as the capping agent was established for controlling pyraclostrobin (PYR) release. The results showed the loading capacity of PYR@MSNs-TA-Cu nanoparticles for pyraclostrobin was 15.7 ± 0.5% and the TA-Cu complexes deposited on the MSNs surface could protect pyraclostrobin against photodegradation effectively. The nanoparticles had excellent pH responsive release performance due to the decomposition of TA-Cu complexes under the acid condition, which showed 8.53 ± 0.37%, 82.38 ± 1.67% of the encapsulated pyraclostrobin were released at pH 7.4, pH 4.5 after 7 d respectively. The contact angle and adhesion work of PYR@MSNs-TA-Cu nanoparticles on rice foliage were 86.3° ± 2.7° and 75.8 ± 3.1 mJ/m2 after 360 s respectively, indicating that TA on the surface of the nanoparticles could improve deposition efficiency and adhesion ability on crop foliage. The control effect of PYR@MSNs-TA-Cu nanoparticles against Rhizoctonia solani with 400 mg/L of pyraclostrobin was 85.82% after 7 d, while that of the same concentration of pyraclostrobin EC was 53.05%. The PYR@MSNs-TA-Cu nanoparticles did not show any phytotoxicity to the growth of rice plants. Meanwhile, the acute toxicity of PYR@MSNs-TA-Cu nanoparticles to zebrafish was decreased more than 9-fold compared with that of pyraclostrobin EC. Thus, pH-responsive PYR@MSNs-TA-Cu nanoparticles have great potential for enhancing targeting and environmental safety of the active ingredient.


Assuntos
Nanopartículas , Peixe-Zebra , Animais , Meio Ambiente , Concentração de Íons de Hidrogênio , Porosidade , Rhizoctonia , Dióxido de Silício , Estrobilurinas
4.
Leuk Lymphoma ; 62(7): 1574-1584, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33682607

RESUMO

This study aimed to explore the role of small nucleolar RNA host gene 14 (SNHG14) in the pathogenesis of diffuse large-B-cell lymphoma (DLBCL). DLBCL cell lines (OCI-Ly7 and OCI-Ly3) and specimens from patients were collected to evaluate the roles of SNHG14 in DLBCL pathogenesis. The results showed that SNHG14 expression increased and miR-152-3p expression decreased in DLBCL tissues and cell lines, indicating a negative correlation between miR-152-3p and SNHG14 expression. Moreover, SNHG14 was found to promote DLBCL growth, migration, and EMT-like processes in vitro, and directly inhibits miR-152-3p gene expression via sequestration of the miR-152-3p transcripts in DLBCL. Additionally, SNHG14/miR-152-3p inhibits apoptosis and promotes cell proliferation on cytotoxic T lymphocytes (CTLs) in DLBCL via the PD-1/PD-L1 checkpoint. Furthermore, both the immune escape and progression of DLBCL are advanced by SNHG14 expression via its interactions with miR-152-3p. Collective, this suggests that SNHG14 is a potential diagnostic, prognostic, and therapeutic target for DLBCL.


Assuntos
Evasão da Resposta Imune , Linfoma Difuso de Grandes Células B , MicroRNAs , RNA Longo não Codificante , Carcinogênese , Humanos , Linfoma Difuso de Grandes Células B/genética , MicroRNAs/genética , RNA Longo não Codificante/genética
5.
J Agric Food Chem ; 69(8): 2382-2391, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33605718

RESUMO

Considering the severity of plant pathogen resistance toward commonly used agricultural microbicides, as well as the potential threats of agrichemicals to the eco-environment, there is a pressing need for antimicrobial approaches that are capable of inactivating pathogens efficiently without the risk of inducing resistances and harm. In this work, a porphyrin metal-organic framework (MOF) nanocomposite was constructed by incorporating 5,10,15,20-tetrakis(1-methyl-4-pyridinio)porphyrin tetra(p-toluenesulfonate) (TMPyP) as a photosensitizer (PS) in the cage of a variant MOF (HKUST-1) to efficiently produce singlet oxygen (1O2) to inactivate plant pathogens under light irradiation. The results showed that the prepared PS@MOF had a loading rate of PS about 12% (w/w) and excellent and broad-spectrum photodynamic antimicrobial activity in vitro against three plant pathogenic fungi and two pathogenic bacteria. Moreover, PS@MOF showed outstanding control efficacy against Sclerotinia sclerotiorum on cucumber in the pot experiment. Allium cepa chromosome aberration assays and safety evaluation on cucumber and Chinese cabbage indicated that PS@MOF had no genotoxicity and was safe to plants. Thus, porphyrin MOF demonstrated a great potential as an alternative and efficient new microbicide for sustainable plant disease management.


Assuntos
Anti-Infecciosos , Estruturas Metalorgânicas , Porfirinas , Anti-Infecciosos/farmacologia , Ascomicetos , Gerenciamento Clínico , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia
6.
Biomed Pharmacother ; 133: 110983, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33190036

RESUMO

Zinc (Zn) is the second most abundant necessary trace element in the human body. It is reported that zinc deficiency (ZD) promotes many types of cancer progression through multiple signal pathways. It is well known that oxidative stress, DNA damage, DNA repair, cell cycle, cell apoptosis, metabolic alterations, microRNAs abnormal expression, and inflammation level are closely related to cancer development. Cumulative evidence suggests that ZD influences these biological functions. This review explores the latest advances in understanding the role of ZD in tumorigenesis. Fully comprehending the potential mechanisms of ZD-induced tumors may provide novel clues for prevention and clinical treatment of cancers.


Assuntos
Transformação Celular Neoplásica , Deficiências Nutricionais/complicações , Neoplasias/etiologia , Zinco/deficiência , Animais , Apoptose , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Dano ao DNA , Reparo do DNA , Deficiências Nutricionais/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Estresse Oxidativo , Transdução de Sinais
7.
Adv Sci (Weinh) ; 7(23): 2001899, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33304751

RESUMO

Highly efficient removal of bilirubin from blood by hemoperfusion for liver failure therapy remains a challenge in the clinical field due to the low adsorption capacity and slow adsorption kinetics of currently used bilirubin adsorbents (e.g., activated carbon and ion-exchange resin). Recently, porous aromatic frameworks (PAFs) with high surface areas, tunable structures, and remarkable stability provide numerous possibilities to obtain satisfying adsorbents. Here, a cationic PAF with more mesopores, named iPAF-6, is successfully constructed via a de novo synthetic strategy for bilirubin removal. The prepared iPAF-6 exhibits a record-high adsorption capacity of 1249 mg g-1 and can adsorb bilirubin from 150 mg L-1 to normal concentration in just 5 min. Moreover, iPAF-6 shows a removal efficiency of 96% toward bilirubin in the presence of 50 g L-1 bovine serum albumin. It is demonstrated that positively charged aromatic frameworks and large pore size make a significant contribution to its excellent adsorption ability. More notably, iPAF-6/polyethersulfone composite fibers or beads are fabricated for practical hemoperfusion adsorption, which also show better removal performance than commercial adsorbents. This work can offer a new possibility for designing PAF-based bilirubin adsorbents with an appealing application prospect.

8.
PLoS One ; 15(10): e0240348, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33052956

RESUMO

Coronavirus disease 2019 (COVID-19) was first identified in December 2019 in Wuhan, China as an infectious disease, and has quickly resulted in an ongoing pandemic. A data-driven approach was developed to estimate medical resource deficiencies due to medical burdens at county level during the COVID-19 pandemic. The study duration was mainly from February 15, 2020 to May 1, 2020 in the U.S. Multiple data sources were used to extract local population, hospital beds, critical care staff, COVID-19 confirmed case numbers, and hospitalization data at county level. We estimated the average length of stay from hospitalization data at state level, and calculated the hospitalized rate at both state and county level. Then, we developed two medical resource deficiency indices that measured the local medical burden based on the number of accumulated active confirmed cases normalized by local maximum potential medical resources, and the number of hospitalized patients that can be supported per ICU bed per critical care staff, respectively. Data on medical resources, and the two medical resource deficiency indices are illustrated in a dynamic spatiotemporal visualization platform based on ArcGIS Pro Dashboards. Our results provided new insights into the U.S. pandemic preparedness and local dynamics relating to medical burdens in response to the COVID-19 pandemic.


Assuntos
Infecções por Coronavirus/epidemiologia , Alocação de Recursos para a Atenção à Saúde/estatística & dados numéricos , Recursos em Saúde/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Análise Espaço-Temporal , COVID-19 , Infecções por Coronavirus/economia , Efeitos Psicossociais da Doença , Humanos , Pandemias/economia , Pneumonia Viral/economia , Estados Unidos
9.
Angew Chem Int Ed Engl ; 59(40): 17726-17731, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32618078

RESUMO

Triplet energy transfer from inorganic nanocrystals to molecular acceptors has attracted strong attention for high-efficiency photon upconversion. Here we study this problem using CsPbBr3 and CdSe nanocrystals as triplet donors and carboxylated anthracene isomers as acceptors. We find that the position of the carboxyl anchoring group on the molecule dictates the donor-acceptor coupling to be either through-bond or through-space, while the relative strength of the two coupling pathways is controlled by the wavefunction leakage of nanocrystals that can be quantitatively tuned by nanocrystal sizes or shell thicknesses. By simultaneously engineering molecular geometry and nanocrystal wavefunction, energy transfer and photon upconversion efficiencies of a nanocrystal/molecule system can be improved by orders of magnitude.

10.
J Neurol ; 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32474658

RESUMO

Oxaliplatin (OXA) is a commonly used platinum-based chemotherapy drug for colorectal cancer. OXA-induced peripheral neurotoxcity (OIPN) is a comprehensive adverse reaction of OXA. OIPN can be divided into acute and chronic types according to clinical features and different mechanisms. The main clinical features of acute OIPN are cold-sensitive sensory symptoms and neuropathic pain in limbs. In addition to the above symptoms, chronic OIPN also produces autonomic nerve dysfunction. The most important mechanism involved in acute OIPN is the alteration of voltage-gated Na + channels, and nuclear DNA damage in chronic OIPN. There are some methods like reducing exposure to cold, calcium and magnesium salts, amifostine could be beneficial in acute OIPN prevention and dose modification, changing in schedule glutathione, duloxetine, selective serotonin reuptake inhibitors, carbonic anhydrase inhibitor in chronic OIPN prevention. Recent updates are provided in this article in relation to the clinical features, potential mechanisms, prevention and treatment of OIPN.

11.
Adv Mater ; 32(30): e1907449, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32567202

RESUMO

Precise tailoring of pore chemistry is indispensable for efficient membrane gas separation, particularly for the challenging acetylene system. Here, a strategy called "anion substitution" is reported, to strengthen the interaction between anions and acetylene within the pores, for radically improving gas selectivity and permeability. The anions F- and OH- are infixed in iPAF-1 to replace the original Cl- ion. Their small anionic radii allow retention of the original high porosity of iPAF-1-Cl in iPAF-1-F and iPAF-1-OH. Highly basic F- and OH- confined in the pores attract acidic acetylene strongly and preferentially. Nanoparticles of iPAF-1 are processed to form mixed matrix membranes, represented by iPAF-1-OH/6FDA-ODA. The prepared membranes exhibit remarkable performance in separating acetylene from ethylene and ethane. Transplantation of porous and functional iPAF-1-OH into 6FDA-ODA significantly enhances both acetylene permeability (sevenfold) and permselectivity (fivefold) for acetylene over ethylene and ethane, which is crucial for membrane acetylene gas separation.

12.
ACS Appl Mater Interfaces ; 12(27): 30474-30482, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32588621

RESUMO

Extracting gold from wastes of electronic equipment (e-waste) is a sustainable strategy for the recovery of the precious metal, reducing environmental pollution, and addressing the growing demands for gold resources. In this work, we synthesized a thiourea-modified porous aromatic framework (PAF-1-thiourea) with exceptional gold-extraction ability. The optimum adsorption capacity for PAF-1-thiourea to gold reaches up to 2629.87 mg g-1. The adsorption process can be well fitted according to the pseudo-second-order kinetic model and Langmuir model, featuring strong affinity caused by strong soft-soft interactions between Au(III) and the S and N donor atoms of the modified PAF and the electrostatic interactions between protonated amino groups and AuCl4-. PAF-1-thiourea was especially capable of extracting gold rapidly and efficiently (capturing 98.73% of gold within 5 min) from a central processing unit (CPU) in extremely acidic conditions. It is found that PAF-1-thiourea captures gold ions and simultaneously converts it to a Au(0) solid, obtaining gold with purity up to 23.5 karat. PAF-1-thiourea with its high acid resistance and anti-interference against cheap metals in the recovery process presents a practical means to extract gold from e-waste.

13.
Clin Endocrinol (Oxf) ; 93(4): 489-498, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32379941

RESUMO

BACKGROUND AND OBJECTIVE: Thyroid cancer (TC) is the most common endocrine system tumour. Several studies had revealed the potential of circulating microRNAs (miRNAs) as novel biomarkers for the diagnosis of TC. The purpose of this meta-analysis is to summarize published studies and evaluate the diagnostic accuracy of circulating miRNAs in TC detection. METHODS: In this meta-analysis, we systematically searched three databases: PubMed, EMBASE and Cochrane Library. We used the bivariate mixed-effects regression model to calculate the pooled diagnostic parameters and conduct the summary receiver operator characteristic curve (SROC). All calculations were performed using stata software. RESULTS: Thirty-five studies from 9 articles, including 663 TC patients, 519 patients with benign thyroid nodules (BTNs), and 84 healthy controls were included in this meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and area under the SROC curve (AUC) were 0.81 (95% CI 0.75-0.86), 0.81 (95% CI 0.75-0.86), 4.3 (95% CI 3.2-5.6), 0.24 (95% CI 0.18-0.31), 18 (95% CI 12-28) and 0.88 (95% CI 0.85-0.90), respectively in BTN controls, and 0.81 (95% CI 0.75-0.86), 0.85 (95% CI 0.75-0.91), 5.3 (95% CI 3.3-8.7), 0.23 (95% CI 0.18-0.29), 24 (95% CI 14-39), 0.89 (95% CI 0.86-0.91) in healthy controls. The subgroup analysis found that multiple miRNA assays had higher diagnostic accuracy than single miRNA assays with sensitivity of 0.88, specificity of 0.89 and AUC of 0.94. CONCLUSION: Circulating miRNAs have good values to diagnose TC and distinguish TC patients from BTN patients. MiRNAs can assist in the diagnosis of malignancy and avoid unnecessary surgery. In summary, circulating miRNAs should be added to our current clinical tools.

14.
J Phys Chem Lett ; 11(6): 2247-2255, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32119553

RESUMO

Two-dimensional (2D) organic-inorganic hybrid perovskites are promising materials for next-generation optoelectronic devices owning to their structural and functional versatility and enhanced ambient stability. Recent studies have started to focus on engineering the molecular properties of the organic cations to induce inorganic-to-organic energy/charge transfer for new functionalities, yet many puzzles regarding the inorganic-organic interaction mechanisms remain to be resolved. Here we fabricate 2D lead halide perovskites containing naphthalene methylamine (NMA) cations to study naphthalene triplet sensitization by inorganic excitons. We find that triplet sensitization proceeds via a two-step mechanism initiated by subpicosecond hole transfer from the inorganic layer to naphthalene. We also provide spectroscopic evidence for triplet excimer formation, i.e., the association between triplet and ground state molecules. The intensity ratio between the excimer and triplet emissions can be tuned via the percentage of the NMA cations in the organic layer, offering a route to tunable white-light emitters using 2D hybrid perovskites.

15.
Chem Rev ; 120(16): 8934-8986, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32101403

RESUMO

Porous aromatic frameworks (PAFs) represent an important category of porous solids. PAFs possess rigid frameworks and exceptionally high surface areas, and, uniquely, they are constructed from carbon-carbon-bond-linked aromatic-based building units. Various functionalities can either originate from the intrinsic chemistry of their building units or are achieved by postmodification of the aromatic motifs using established reactions. Specially, the strong carbon-carbon bonding renders PAFs stable under harsh chemical treatments. Therefore, PAFs exhibit specificity in their chemistry and functionalities compared with conventional porous materials such as zeolites and metal organic frameworks. The unique features of PAFs render them being tolerant of severe environments and readily functionalized by harsh chemical treatments. The research field of PAFs has experienced rapid expansion over the past decade, and it is necessary to provide a comprehensive guide to the essential development of the field at this stage. Regarding research into PAFs, the synthesis, functionalization, and applications are the three most important topics. In this thematic review, the three topics are comprehensively explained and aptly exemplified to shed light on developments in the field. Current questions and a perspective outlook will be summarized.

16.
Chem Sci ; 10(33): 7695-7701, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31588317

RESUMO

Two homologous covalent triazine frameworks (CTFs) have been developed for the first time as anode materials for high performance K-ion batteries (KIBs). The two-dimensional sheet-like structure as well as the regular channels in CTFs enable the process of intercalation/deintercalation of K-ions into/from the CTF interlayers reversibly. Particularly, a size effect of the porous structure is found to dominate the K-ion storage behavior. CTF-0 with a smaller pore size displays a higher K-ion storage capacity than CTF-1. Molecular simulations reveal the operation mechanism, showing that the depotassiation process in CTF-0 is exothermic while the depotassiation in CTF-1 is endothermic, which makes the deintercalation of K-ions from CTF-0 more feasible than from CTF-1 and contributes to the higher reversible capacity of CTF-0. This work provides a promising strategy for rational design of high-performance organic anode materials by structural modulation at the molecular scale.

17.
Adv Mater ; 31(40): e1902444, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31418940

RESUMO

Compositional catalysts based on porous supports and incorporated catalytic nanoparticles have achieved great successes during the past decades. However, rational design of synergic catalysts and modulating the interactions between functional supports and catalytic sites are still far from being well developed. In this work, aiming at overcoming the difficulties of comprehensive screening of porous supports and correspondingly matched catalytic sites, a cationic porous aromatic framework as a capturing platform and polyoxometalate anions as conversion materials are separately designed, and their combination is modularly controlled. The resulting composites show higher catalytic activities than the corresponding conversion sites themselves. Notably, the resulting composites uncommonly exhibit increased surface area and enlarged pore openings after the incorporation of nanoparticles, and lead to the promotion of mass transfer within the porous supports. The emergence of a hierarchical structure with increased surface area induced by guest loading is desired in heterogeneous catalysis. The reciprocal modulation of both capture and conversion materials results in enhanced conversion and increased reaction rate, indicating the successful preparation of synergic catalysts by this separate design approach.

18.
Mol Med Rep ; 20(3): 2459-2467, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31322189

RESUMO

To evaluate the prognostic value of the microRNA (miR)­17­92 gene cluster, the expression of miR­17­92 in B­cell non­Hodgkin's lymphoma (B­NHL) was examined. Patients with B­NHL, who received therapy in the Department of Hematology, Harbin Medical University Cancer Hospital between January 2012 and October 2014, were enrolled in the study. The expression of the miR­17­92 cluster in tumor tissue samples was detected by reverse transcription­quantitative polymerase chain reaction analysis. The overall survival (OS) and event­free survival (EFS) times were also investigated by the Kaplan­Meier method and comparisons between groups were estimated using a log­rank test. Three types of lymphoid cancer cells with wild­type (WT), knockout of miR­17­92 (KO), and overexpression of miR­17­92 (TG), were utilized to establish a tumor xenograft model, and a reactive hyperplasia lymph cell was used as a control. The tumor incubation times and weights were examined. A total of 71 patients with B­NHL were registered. No significant correlations were identified between the expression of miR­17­92 and clinical factors (P>0.05). Members of the miR­17­92 cluster exhibited various expression in the subtypes of B­NHL, and the difference between follicular lymphoma (FL) and germinal center B­cell like (GBC) was most marked. The overexpression of miR­18, miR­19a, and miR­92a induced a marked reduction in the OS of patients with B­NHL, and high­levels of miR­19a and miR­92a led to a decline in EFS. The overexpression of miR­17­92 shortened the duration of incubation required for visualization of the xenograft tumor, whereas knockout led to inhibition of tumor formation. The expression of miR­17­92 in FL differed significantly from that in GBC, and miR­19a may have a crucial effect on the OS and EFS of patients with B­NHL.


Assuntos
Regulação Neoplásica da Expressão Gênica , Linfoma de Células B/genética , MicroRNAs/genética , Família Multigênica , Animais , Feminino , Humanos , Linfoma de Células B/patologia , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Células Tumorais Cultivadas
19.
Sensors (Basel) ; 19(11)2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31185598

RESUMO

Accurate position information plays an important role in wireless sensor networks (WSN), and cooperative positioning based on cooperation among agents is a promising methodology of providing such information. Conventional cooperative positioning algorithms, such as least squares (LS), rely on approximate position estimates obtained from prior measurements. This paper explores the fundamental mechanism underlying the least squares algorithm's sensitivity to the initial position selection and approaches to dealing with such sensitivity. This topic plays an essential role in cooperative positioning, as it determines whether a cooperative positioning algorithm can be implemented ubiquitously. In particular, a sufficient and unnecessary condition for the least squares cost function to be convex is found and proven. We then propose a robust algorithm for wireless sensor network positioning that transforms the cost function into a globally convex function by detecting the null space of the relative angle matrix when all the targets are located inside the convex polygon formed by its neighboring nodes. Furthermore, we advance one step further and improve the algorithm to apply it in both the time of arrival (TOA) and angle of arrival/time of arrival (AOA/TOA) scenarios. Finally, the performance of the proposed approach is quantified via simulations, and the results show that the proposed method has a high positioning accuracy and is robust in both line-of-sight (LOS) and non-line-of-sight (NLOS) positioning environments.

20.
ACS Appl Mater Interfaces ; 11(18): 16662-16673, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31009202

RESUMO

Water contamination by emerging organic pollutants, such as pharmaceuticals and personal care products (PPCPs), is becoming more and more serious. Porous aromatic frameworks (PAFs) are considered as promising adsorbents to remove the PPCPs. To overcome the limitation of PAFs in their powder forms for large-scale applications, herein, we proposed a strategy to covalently anchor PAFs onto electrospun polymer fiber membranes. Polyaniline (PANI) played the role of aromatic seed layer, which was coated on the electrospun polyacrylonitrile (PAN) fiber membrane first. Then, PAF-45 modification was in situ synthesized in the presence of the PANI-coated electrospun PAN fiber membrane. This study could make the PAF-based materials be handled more easily and improve the surface area of electrospun fiber membrane. The obtained composite adsorbent (PAF-45-PP FM) was applied for the adsorption of three PPCPs: ibuprofen (IBPF), chloroxylenol (CLXN), and N, N-diethyl-meta-toluamide (DEET), which exhibited high adsorption capacity and good recycling ability. According to the Langmuir model, the maximum adsorption capacities of PAF-45-PP FM toward IBPF, CLXN and DEET were 613.50, 429.18, and 384.61 mg/g, respectively. In addition, after ten adsorption-desorption cycles, the adsorption capacities toward the three PPCPs decreased slightly. Through an adsorption comparison test, the adsorption capacity of PAF-45-PP FM almost attributed to the loading PAF-45. The adsorption mechanism analysis illustrated that there were pore capture, hydrophobic interaction and π-π interaction between PPCPs and PAF-45-PP FM. Therefore, the PAF-45-PP FM can be potential adsorbents to purify water contaminated with PPCPs.


Assuntos
Adsorção , DEET/química , Ibuprofeno/química , Poluentes Químicos da Água/química , Xilenos/química , Resinas Acrílicas/química , Compostos de Anilina/química , DEET/toxicidade , Humanos , Interações Hidrofóbicas e Hidrofílicas , Ibuprofeno/toxicidade , Membranas Artificiais , Preparações Farmacêuticas/química , Fenóis/química , Porosidade , Poluentes Químicos da Água/toxicidade , Purificação da Água , Xilenos/toxicidade
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