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1.
Sensors (Basel) ; 23(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37896631

RESUMO

Global precipitation is becoming increasingly intense due to the extreme climate. Therefore, creating new technology to manage water resources is crucial. To create a sustainable urban and ecological environment, a water level and water quality control system implementing artificial intelligence is presented in this research. The proposed smart monitoring system consists of four sensors (two different liquid level sensors, a turbidity and pH sensor, and a water oxygen sensor), a control module (an MCU, a motor, a pump, and a drain), and a power and communication system (a solar panel, a battery, and a wireless communication module). The system focuses on low-cost Internet of Things (IoT) devices along with low power consumption and high precision. This proposal collects rainfall from the preceding 10 years in the application region as well as the region's meteorological bureau's weekly weather report and uses artificial intelligence to compute the appropriate water level. More importantly, the adoption of dynamic adjustment systems can reserve and modify water resources in the application region more efficiently. Compared to existing technologies, the measurement approach utilized in this study not only achieves cost savings exceeding 60% but also enhances water level measurement accuracy by over 15% through the successful implementation of water level calibration decisions utilizing multiple distinct sensors. Of greater significance, the dynamic adjustment systems proposed in this research offer the potential for conserving water resources by more than 15% in an effective manner. As a result, the adoption of this technology may efficiently reserve and distribute water resources for smart cities as well as reduce substantial losses caused by anomalous water resources, such as floods, droughts, and ecological concerns.

2.
Anal Chem ; 93(46): 15517-15524, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34726908

RESUMO

Precisely detecting the catalysts' hot spots temperature in situ instantly during photocatalysis is a great challenge but extremely important for chemical reactions. However, no efficient method has been developed to instantly detect the hot spots temperature in situ during photocatalysis. Herein, we designed a simple and convenient method to measure the instant hot spots temperature in situ on the nanostructure surface during photocatalysis by operando Raman spectroscopy using 4-methoxyphenyl isocyanide (MI) as the probe molecule. The νN≡C frequency of MI varied linearly with temperature, which is caused by the orientation change of the MI induced by temperature, leading to the change in the frequency of the νN≡C bond that directly interacts with the nanostructure surface. Using in situ surface-enhanced Raman spectroscopy (SERS), the surface temperature of the catalysts illuminating for each time can be measured instantly. Interestingly, the catalytic activity of the hydrogen evolution reaction (HER) for the Au-Ag/Ag2S heterojunction nanorods (HJNRs) are higher than that for the Ag-Au-Ag HJNRs, although they have a lower surface temperature during photocatalysis; therefore, hot carriers and electronic structure contributed more to the catalytic activity of the Au-Ag/Ag2S HJNRs than that of the Ag-Au-Ag HJNRs. Such an instant hot spots temperature detecting method of catalysts can greatly facilitate the analysis of the mechanism of catalytic processes.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Ouro , Prata , Temperatura
3.
Pharmacol Res ; 147: 104328, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288080

RESUMO

A global transcriptional regulator, MgrA, was previously identified as a key determinant of virulence in Staphylococcus aureus. An 80% EtOH extract of Uncaria gambier was found to attenuate the virulence of S. aureus via its effects on MgrA. Using bioassay-guided fractionation, a polyphenolic polymer, uncariitannin, was found to be the main bioactive constituent of the extract, and its structure was characterized using spectral and chemical analysis. The molecular weight and polydispersity of uncariitannin were determined by gel permeation chromatography-refractive index-light scattering analysis. An electrophoretic mobility shift assay showed that uncariitannin could effectively inhibit the interaction of MgrA with DNA in a dose-dependent manner. Treatment with uncariitannin could decrease the mRNA and protein levels of Hla in both the S. aureus Newman and USA300 LAC strains. Further analysis of Hla expression levels in the Newman ΔmgrA and Newman ΔmgrA/pYJ335-mgrA strains indicated that uncariitannin altered Hla expression primarily in an MgrA-dependent manner. A mouse model of infection indicated that uncariitannin could attenuate MRSA virulence. In conclusion, uncariitannin may be a potential candidate for further development as an antivirulence agent for the treatment of S. aureus infection.


Assuntos
Antibacterianos , Polímeros , Polifenóis , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Uncaria , Virulência/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Feminino , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos Endogâmicos BALB C , Miocárdio/patologia , Polímeros/farmacologia , Polímeros/uso terapêutico , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Baço/efeitos dos fármacos , Baço/patologia , Infecções Estafilocócicas/patologia , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Staphylococcus aureus/patogenicidade
4.
Small ; 14(12): e1703334, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29394467

RESUMO

This paper introduces super absorbent polymer valves and colorimetric sensing reagents as enabling components of soft, skin-mounted microfluidic devices designed to capture, store, and chemically analyze sweat released from eccrine glands. The valving technology enables robust means for guiding the flow of sweat from an inlet location into a collection of isolated reservoirs, in a well-defined sequence. Analysis in these reservoirs involves a color responsive indicator of chloride concentration with a formulation tailored to offer stable operation with sensitivity optimized for the relevant physiological range. Evaluations on human subjects with comparisons against ex situ analysis illustrate the practical utility of these advances.


Assuntos
Colorimetria/métodos , Microfluídica/métodos , Polímeros/química , Suor/química , Humanos , Dispositivos Lab-On-A-Chip , Pele/metabolismo
5.
J Recept Signal Transduct Res ; 37(2): 189-199, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27401208

RESUMO

PURPOSE: The transforming growth factor-beta (TGF-ß) pathway is an important in the initiation and progression of cancer. Due to a strong association between an elevated colorectal cancer risk and increase fecal excretion of cholest-4-en-3-one, we aim to determine the effects of cholest-4-en-3-one on TGF-ß signaling in the mink lung epithelial cells (Mv1Lu) and colorectal cancer cells (HT29) in vitro. METHODS: The inhibitory effects of cholest-4-en-3-one on TGF-ß-induced Smad signaling, cell growth inhibition, and the subcellular localization of TGF-ß receptors were investigated in epithelial cells using a Western blot analysis, luciferase reporter assays, DNA synthesis assay, confocal microscopy, and subcellular fractionation. RESULTS: Cholest-4-en-3-one attenuated TGF-ß signaling in Mv1Lu cells and HT29 cells, as judged by a TGF-ß-specific reporter gene assay of plasminogen activator inhibitor-1 (PAI-1), Smad2/3 phosphorylation and nuclear translocation. We also discovered that cholest-4-en-3-one suppresses TGF-ß responsiveness by increasing lipid raft and/or caveolae accumulation of TGF-ß receptors and facilitating rapid degradation of TGF-ß and thus suppressing TGF-ß-induced signaling. CONCLUSIONS: Our results suggest that cholest-4-en-3-one inhibits TGF-ß signaling may be due, in part to the translocation of TGF-ß receptor from non-lipid raft to lipid raft microdomain in plasma membranes. Our findings also implicate that cholest-4-en-3-one may be further explored for its potential role in colorectal cancer correlate to TGF-ß deficiency.


Assuntos
Neoplasias Colorretais/genética , Inibidor 1 de Ativador de Plasminogênio/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Fator de Crescimento Transformador beta1/genética , Animais , Colestenonas/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Células Epiteliais/patologia , Células HT29 , Humanos , Pulmão/patologia , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/genética , Microdomínios da Membrana/metabolismo , Vison/genética , Fosforilação , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Proteínas Serina-Treonina Quinases/biossíntese , Proteólise/efeitos dos fármacos , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/biossíntese
6.
Theor Appl Genet ; 127(11): 2515-24, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25223543

RESUMO

KEY MESSAGE: A minor QTL for heading date located on the long arm of rice chromosome 1 was delimitated to a 95.0-kb region using near isogenic lines with sequential segregating regions. Heading date and grain yield are two key factors determining the commercial potential of a rice variety. In this study, rice populations with sequential segregating regions were developed and used for mapping a minor QTL for heading date, qHd1. A total of 18 populations in six advanced generations through BC2F6 to BC2F11 were derived from a single BC2F3 plant of the indica rice cross Zhenshan 97 (ZS97)///ZS97//ZS97/Milyang 46. The QTL was delimitated to a 95.0-kb region flanked by RM12102 and RM12108 in the terminal region of the long arm of chromosome 1. Results also showed that qHd1 was not involved in the photoperiodic response, having an additive effect ranging from 2.4 d to 2.9 d observed in near isogenic lines grown in the paddy field and under the controlled conditions of either short day or long day. The QTL had pleiotropic effects on yield traits, with the ZS97 allele delaying heading and increasing the number of spikelets per panicle, the number of grains per panicle and grain yield per plant. The candidate region contains ten annotated genes including two genes with functional information related to the control of heading date. These results lay a foundation for the cloning of qHd1. In addition, this kind of minor QTLs could be of great significance in rice breeding for allowing minor adjustment of heading date and yield traits.


Assuntos
Mapeamento Cromossômico , Pleiotropia Genética , Oryza/crescimento & desenvolvimento , Oryza/genética , Locos de Características Quantitativas , Alelos , Cruzamento , Cromossomos de Plantas , Marcadores Genéticos , Fenótipo , Fotoperíodo
7.
Toxicol Appl Pharmacol ; 267(1): 113-24, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23274516

RESUMO

Compound C, a well-known inhibitor of the intracellular energy sensor AMP-activated protein kinase (AMPK), has been reported to cause apoptotic cell death in myeloma, breast cancer cells and glioma cells. In this study, we have demonstrated that compound C not only induced autophagy in all tested skin cancer cell lines but also caused more apoptosis in p53 wildtype skin cancer cells than in p53-mutant skin cancer cells. Compound C can induce upregulation, phosphorylation and nuclear translocalization of the p53 protein and upregulate expression of p53 target genes in wildtype p53-expressing skin basal cell carcinoma (BCC) cells. The changes of p53 status were dependent on DNA damage which was caused by compound C induced reactive oxygen species (ROS) generation and associated with activated ataxia-telangiectasia mutated (ATM) protein. Using the wildtype p53-expressing BCC cells versus stable p53-knockdown BCC sublines, we present evidence that p53-knockdown cancer cells were much less sensitive to compound C treatment with significant G2/M cell cycle arrest and attenuated the compound C-induced apoptosis but not autophagy. The compound C induced G2/M arrest in p53-knockdown BCC cells was associated with the sustained inactive Tyr15 phosphor-Cdc2 expression. Overall, our results established that compound C-induced apoptosis in skin cancer cells was dependent on the cell's p53 status.


Assuntos
Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Pirazóis/antagonistas & inibidores , Pirimidinas/antagonistas & inibidores , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Proteína Supressora de Tumor p53/fisiologia , Proteínas Quinases Ativadas por AMP/fisiologia , Apoptose/fisiologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Linhagem Celular Tumoral , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Neoplasias Cutâneas/enzimologia
8.
Dalton Trans ; 52(23): 8051-8057, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37232003

RESUMO

A ruthenium complex [Ru(phen)2(phen-5-amine)-C14] (Ru-C14) with broad-spectrum antibacterial activity was designed and synthesized; positively charged Ru-C14 could target bacteria via electrostatic interactions and showed high binding effectiveness to cell membranes. In addition, Ru-C14 could act as a photosensitizer. Under 465 nm light irradiation, Ru-C14 could generate 1O2, thus disrupting the bacterial intracellular redox balance and leading to bacterial death. Ru-C14 also exhibited minimum inhibitory concentration values of 6.25 µM against Escherichia coli and 3.125 µM against Staphylococcus aureus; these values are lower than those of streptomycin and methicillin. This work combined the merits of cell membrane targeting and photodynamic therapy for antibacterial activity. The findings might open up a new avenue for effective anti-infection treatment and other medical applications.


Assuntos
Complexos de Coordenação , Rutênio , Fármacos Fotossensibilizantes/química , Rutênio/química , Complexos de Coordenação/química , Antibacterianos/química , Membrana Celular
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 272: 120963, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35144079

RESUMO

In this study, we prepared nitrogen-doped carbon dots (xNCDs) using hydrothermally-treated bitter tea oil residue with urea for the detection of metal ions by monitoring the photoluminescence quenching. The quantum yields of the xNCDs increased from approximately 3.85% (CDs) to 5.5% (3NCDs) and 7.2% (1NCDs), revealing that nitrogen doping effectively increases the fluorescence emission. The increased emission of the xNCDs can be attributed to radiative recombination resulting from the π-π* transition of the C=C or the n-π* transition between the C=O or N=O of sp3 units. Moreover, the CDs have abundant surface-attached phenolic and hydroxyl groups that coordinate with Fe3+ ions and quench the fluorescence. Conversely, Hg2+ ions preferentially adsorb on nitrogen-containing groups, such as amide-carbonyl groups (O=C-NH2) and pyridinic and pyrrolic functionalities, on the surface of the NCDs owing to their strong affinity, quenching the substantial photoluminescence emissions. Our results suggest that bitter tea oil residue-derived carbon dots can be used to selectively detect metal ions, such as Fe3+ and Hg2+, by doping with nitrogen using urea as a nitrogen precursor.


Assuntos
Mercúrio , Pontos Quânticos , Carbono/química , Íons , Mercúrio/análise , Nitrogênio/química , Pontos Quânticos/química , Espectrometria de Fluorescência , Chá , Ureia
10.
Huan Jing Ke Xue ; 43(10): 4622-4629, 2022 Oct 08.
Artigo em Zh | MEDLINE | ID: mdl-36224147

RESUMO

In order to understand the composition and accumulation characteristics of phthalates esters (PAEs) in agricultural soils in Gansu province, a total of 41 soil samples from four agricultural soils in Gansu province were collected, and the content of six PAEs compounds was analyzed using a gas chromatography-single quadrupole mass spectrometer (GC-MS). The results showed that the average value of PAEs compounds in agricultural soils in Gansu province was 432.4 µg·kg-1. The detection rates of DMP, DEP, DnBP, DEHP, and DNOP in the soil were 100%, and BBP was not detected. The order of the average value of PAEs content in the four agricultural soils in Gansu province was:greenhouse>farmland (open field)>forest>grassland. The exceeding rates of dibutyl phthalate (DnBP), dimethyl phthalate (DMP), and dimethyl phthalate (DEP) were 94%, 28%, and 27%, and the remaining three did not exceed the standard. The composition of PAEs in different agricultural soils was different due to their different sources. DEHP and DnBP components in the six different PAEs monomers accounted for a higher proportion and were the main pollutants of PAEs in agricultural soils in Gansu province. In this study, the contents of soil PAEs and DEHP were significantly positively correlated with the residual amount of mulch film in the farmland (P<0.05). In general, the content of soil PAEs in the Hexi area of Gansu province was significantly higher than that in the Longdong area.


Assuntos
Dietilexilftalato , Poluentes Ambientais , Ácidos Ftálicos , Poluentes do Solo , 2,4-Dinitrofenol/análogos & derivados , China , Dibutilftalato , Ésteres , Solo , Poluentes do Solo/análise
11.
Nat Biotechnol ; 40(8): 1259-1269, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35301496

RESUMO

Living bacteria therapies have been proposed as an alternative approach to treating a broad array of cancers. In this study, we developed a genetically encoded microbial encapsulation system with tunable and dynamic expression of surface capsular polysaccharides that enhances systemic delivery. Based on a small RNA screen of capsular biosynthesis pathways, we constructed inducible synthetic gene circuits that regulate bacterial encapsulation in Escherichia coli Nissle 1917. These bacteria are capable of temporarily evading immune attack, whereas subsequent loss of encapsulation results in effective clearance in vivo. This dynamic delivery strategy enabled a ten-fold increase in maximum tolerated dose of bacteria and improved anti-tumor efficacy in murine models of cancer. Furthermore, in situ encapsulation increased the fraction of microbial translocation among mouse tumors, leading to efficacy in distal tumors. The programmable encapsulation system promises to enhance the therapeutic utility of living engineered bacteria for cancer.


Assuntos
Escherichia coli , Neoplasias , Animais , Escherichia coli/genética , Escherichia coli/metabolismo , Imunoterapia , Camundongos , Neoplasias/genética , Neoplasias/terapia
12.
Food Funct ; 13(9): 5050-5060, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35403637

RESUMO

Due to the rapid evolution of antibiotic resistance in Staphylococcus aureus, antivirulence therapy may be a promising alternative for the effective control of the spread of resistant pathogens. The Chinese Materia Medica has been widely used for the treatment of diseases and production of health foods, and it remains a valuable resource for the discovery of compounds possessing antivirulence activity. Through a Caenorhabditis elegans infection model, an EtOAc-soluble fraction of 80% EtOH extract of Salvia miltiorrhiza Bunge (SMEA) was found to possess potential anti-infective activity against S. aureus. Then, several in vitro assays indicated that SMEA had robust antivirulence activity at the dose of 400 µg mL-1, reducing hemolytic activity and α-hemolysin expression in S. aureus. Furthermore, at 100 mg kg-1, SMEA reduced abscess formation in the main organs of mice challenged with S. aureus. In order to identify the bioactive components of SMEA and investigate the mechanisms underlying the antivirulence activity, SMEA was separated using bioassay-guided fractionation. As a result, eight compounds were identified in SMEA. Among them, tanshinone IIB (TNB) showed strong antivirulence activity both in vitro and in vivo. Furthermore, at 24 µg mL-1, TNB significantly reduced the expression of RNAIII and psmα, indicating that the mechanism underlying TNB activity was related to the accessory gene regulator quorum sensing system. In conclusion, TNB's antivirulence properties make it a promising candidate for drug development against S. aureus infections.


Assuntos
Anti-Infecciosos , Salvia miltiorrhiza , Infecções Estafilocócicas , Animais , Antibacterianos/metabolismo , Anti-Infecciosos/farmacologia , Camundongos , Percepção de Quorum , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus , Virulência
13.
Genes (Basel) ; 13(8)2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-36011261

RESUMO

Although salinity stress is one of the principal abiotic stresses affecting crop yield, a suitable concentration of NaCl has proven to be useful for increasing crop quality. This study used low salinity (34 mmol/L NaCl) and high salinity (85 mmol/L) to cultivate purple sweetpotato. Using transcriptomics and metabolomics to profile the pathway indicated that glycometabolism, secondary metabolite biosynthesis and the starch catabolic process were the significant pathways under the salinity stress. Further research showed that purple sweetpotato could regulate genes related to the regulation of the cellular Na+, K+, and other ions concentration in response to the low salinity tolerance, but loses this ability under high salinity. Meanwhile, under low salinity, the activity of antioxidant enzymes and their related gene expression are maintained at a high level. The low salinity influences the monosaccharide composition as well as the content and regulation of genes related to starch synthesis. Quality analysis showed that the low salinity could increase the starch content and influence the amylopectin biosynthesis. It suggested that low salinity promotes substance accumulation. High salinity could increase the anthocyanins biosynthesis and low salinity had a significant impact on phenolic acid and flavonol. Finally, the gene expression levels also prove the low salinity could change the composition and content level of the purple sweetpotato. This study showed that an appropriate concentration of NaCl can be used as an elicitor for application in purple sweetpotato planting.


Assuntos
Ipomoea batatas , Adaptação Psicológica , Antocianinas/genética , Antocianinas/metabolismo , Ipomoea batatas/genética , Salinidade , Cloreto de Sódio/metabolismo , Cloreto de Sódio/farmacologia , Amido/metabolismo
14.
Nat Prod Res ; 35(13): 2137-2144, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31512485

RESUMO

One new xanthone, (±) garciesculenxanthone C (1), two new biphenyls, garciesculenbiphenyls A (2) and B (3), together with two known compounds, doitungbiphenyl B (4) and morusignin D (5), were isolated from Garcinia esculenta. The structures of new compounds were elucidated by spectroscopic analysis, and the absolute configuration of (±) garciesculenxanthone C (1) was assigned by a modified Mosher's method. All isolates were evaluated for their antistaphylococcal activities against Staphylococcus aureus Newman, USA300 LAC, USA400 MW2, and Mu50 strains. Among these, (±) garciesculenxanthone C (1) showed the best antistaphylococcal activity, and its effect was determined to be bactericidal by time-kill experiment.


Assuntos
Antibacterianos/farmacologia , Compostos de Bifenilo/isolamento & purificação , Compostos de Bifenilo/farmacologia , Garcinia/química , Prenilação , Staphylococcus aureus/efeitos dos fármacos , Xantonas/isolamento & purificação , Xantonas/farmacologia , Antibacterianos/química , Compostos de Bifenilo/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Testes de Sensibilidade Microbiana , Estereoisomerismo , Xantonas/química
15.
ACS Omega ; 6(48): 33159-33170, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34901667

RESUMO

In this study, we used one-pot A2 + B3 polymerizations to synthesize two aliphatic + alicyclic polymer dots (PDs) having non-conjugated hyperbranched structures, employing two types of dianhydrides as the A2 components, possessing bridged bicyclic alkene (PD-BT) and non-alkene (PD-ET) units, and Jeffamine T403 polyetheramine (T403) as the B3 components. We prepared PD-ET from commercially available ethylenediaminetetraacetic dianhydride (EDTAD, A2) and T403 (B3) and PD-BT from bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BCDA, A2) and T403 (B3). These two types of PDs possessed non-conjugated hyperbranched poly(amic acid) structures with terminal amino functional groups. PD-BT and PD-ET exhibited non-conventional fluorescence with emissions at 435 and 438 nm, respectively, and quantum yields of 12.8 and 14.0%, respectively. The fluorescence intensity of PD-ET was influenced by the pH, but PD-BT was less affected because of its rigid aliphatic bridged bicyclic structure. In aqueous solutions, the sizes of the PD-BT and PD-ET nanoparticles were 3-5 nm, and their net charges can be adjusted by varying the pH. These PDs were non-cytotoxic toward human MCF-7 breast cancer cells and human keratinocyte HaCaT cells at concentrations of 50 µg mL-1 for PD-BT and 500 µg mL-1 for PD-ET. Confocal microscopic bioimaging revealed that the PDs were located within the cells after treatment for 6 h. These PDs were easy to prepare, highly water-soluble, and possessed a large number of peripheral functional groups for further modification. Combined with their non-conventional fluorescence, they appear to have potential uses in bioimaging and as drug-labeling carriers.

16.
ACS Appl Mater Interfaces ; 13(1): 1152-1157, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33350805

RESUMO

Rapid detection of the handiness of chiral molecules is an important topic for pharmaceutical industries because chiral drugs with opposing handiness sometimes exhibit unwanted side effects. In this research, a rapid optical method is proposed to determine the handiness of the chiral drug "Thalidomide". The platform is a large array of three-dimensional (3D) twisted metamaterials fabricated with a novel method by combining nanospherical-lens lithography (NLL) and hole-mask lithography (HML). The fabrication is high-throughput and the twisted metamaterials cover a large area. Strong circular dichroism (CD) response is observed in the near-infrared (NIR) region, which enables the chiral detection to be performed by a low-cost and portable spectroscope system. The proposed nanofabrication method significantly improves the capabilities of NLL and HML, which can be quickly adapted to fabricate various periodic 3D metamaterials. In addition, the results of this research pave the road for the rapid penetration of nanophotonics into the pharmaceutical industries.


Assuntos
Nanoestruturas/química , Talidomida/química , Dicroísmo Circular/métodos , Estereoisomerismo
17.
RSC Adv ; 11(27): 16661-16674, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35479143

RESUMO

In this study we prepared six types of carbon nanodots (CNDs) from natural plant materials - through carbonization of two species of bamboo (Bamboo-I, Bamboo-II) and one type of wood (Wood), and through hydrothermal processing of the stem and root of the herb Mahonia oiwakensis Hayata (MO) and of the agricultural waste of two species of pineapple root (PA, PB). The resulting CNDs were spherical with dimensions on the nanoscale (3-7 nm); furthermore, CND-Bamboo I, CND-Wood, CND-Bamboo II, CND-MO, CND-PA, and CND-PB displayed fluorescence quantum yields of 9.63, 12.34, 0.90, 10.86, 0.35, and 0.71%, respectively. X-ray diffraction revealed that the carbon nanostructures possessed somewhat ordered and disordered lattices, as evidenced by broad signals at values of 2θ between 20 and 30°. CND-Bamboo I, CND-Wood, and CND-Bamboo II were obtained in yields of 2-3%; CND-MO, CND-PA, and CND-PB were obtained in yields of 17.64, 9.36, and 22.47%, respectively. Cytotoxicity assays for mouse macrophage RAW264.7 cells treated with the six types of CNDs and a commercial sample of Ag nanoparticles (NPs) revealed that each of our CNDs provided a cell viability of 90% at 2000 µg mL-1, whereas it was only 20% after treatment with the Ag NPs at 62.5 µg mL-1. The six types of CNDs also displayed low cytotoxicity toward human keratinocyte HacaT cells, human MCF-7 breast cancer cells, and HT-29 colon adenocarcinoma cells when treated at 500 µg mL-1. Moreover, confocal microscopic cell imaging revealed that the fluorescent CND-Bamboo I particles were located on the MCF-7 cell membrane and inside the cells after treatment for 6 and 24 h, respectively. We have thoroughly investigated the photoluminescence properties and carbon nanostructures of these highly dispersed CNDs. Because of the facile green synthesis of these six types of CNDs and their sourcing from abundant natural plants, herbs, and agriculture waste, these materials provide a cost-effective method, with low cytotoxicity and stable fluorescence, for biolabeling and for developing cell nanocarriers.

18.
Front Plant Sci ; 12: 804444, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35126429

RESUMO

Grain size is a key constituent of grain weight and appearance in rice. However, insufficient attention has been paid to the small-effect quantitative trait loci (QTLs) on the grain size. In the present study, residual heterozygous populations were developed for mapping two genetically linked small-effect QTLs for grain size. After the genotyping and the phenotyping of five successive generations, qGS7.1 was dissected into three QTLs and two were selected for further analysis. The qTGW7.2a was finally mapped into a 21.10 kb interval containing four annotated candidate genes. Transcript levels assay showed that the expression of the candidates LOC_Os07g39490 and the LOC_Os07g39500 were significantly reduced in the NIL-qTGW7.2aBG1 . The cytological observation indicated that qTGW7.2a regulated the grain width through controlling the cell expansion. Using the same strategy, qTGW7.2b was fine-mapped into a 52.71 kb interval containing eight annotated candidate genes, showing a significant effect on the grain length and width with opposite allelic directions, but little on the grain weight. Our study provides new genetic resources for yield improvement and for fine-tuning of grain size in rice.

19.
Nat Biotechnol ; 39(10): 1228-1238, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34183859

RESUMO

Temporary cardiac pacemakers used in periods of need during surgical recovery involve percutaneous leads and externalized hardware that carry risks of infection, constrain patient mobility and may damage the heart during lead removal. Here we report a leadless, battery-free, fully implantable cardiac pacemaker for postoperative control of cardiac rate and rhythm that undergoes complete dissolution and clearance by natural biological processes after a defined operating timeframe. We show that these devices provide effective pacing of hearts of various sizes in mouse, rat, rabbit, canine and human cardiac models, with tailored geometries and operation timescales, powered by wireless energy transfer. This approach overcomes key disadvantages of traditional temporary pacing devices and may serve as the basis for the next generation of postoperative temporary pacing technology.


Assuntos
Implantes Absorvíveis , Marca-Passo Artificial , Animais , Bloqueio Atrioventricular/terapia , Modelos Animais de Doenças , Cães , Desenho de Equipamento , Humanos , Camundongos , Coelhos , Ratos , Tecnologia sem Fio
20.
Sci Adv ; 6(35): eabb1093, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32923633

RESUMO

Implantable drug release platforms that offer wirelessly programmable control over pharmacokinetics have potential in advanced treatment protocols for hormone imbalances, malignant cancers, diabetic conditions, and others. We present a system with this type of functionality in which the constituent materials undergo complete bioresorption to eliminate device load from the patient after completing the final stage of the release process. Here, bioresorbable polyanhydride reservoirs store drugs in defined reservoirs without leakage until wirelessly triggered valve structures open to allow release. These valves operate through an electrochemical mechanism of geometrically accelerated corrosion induced by passage of electrical current from a wireless, bioresorbable power-harvesting unit. Evaluations in cell cultures demonstrate the efficacy of this technology for the treatment of cancerous tissues by release of the drug doxorubicin. Complete in vivo studies of platforms with multiple, independently controlled release events in live-animal models illustrate capabilities for control of blood glucose levels by timed delivery of insulin.

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