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1.
Artigo em Inglês | MEDLINE | ID: mdl-38568462

RESUMO

PURPOSE: This study aimed to identify the genetic causes of male infertility and primary ciliary dyskinesia (PCD)/PCD-like phenotypes in three unrelated Han Chinese families. METHODS: We conducted whole-exome sequencing of three patients with male infertility and PCD/PCD-like phenotypes from three unrelated Chinese families. Ultrastructural and immunostaining analyses of patient spermatozoa and respiratory cilia and in vitro analyses were performed to analyze the effects of SPEF2 variants. Intracytoplasmic sperm injection (ICSI) was administered to three affected patients. RESULTS: We identified four novel SPEF2 variants, including one novel homozygous splicing site variant [NC_000005.10(NM_024867.4): c.4447 + 1G > A] of the SPEF2 gene in family 1, novel compound heterozygous nonsense variants [NC_000005.10(NM_024867.4): c.1339C > T (p.R447*) and NC_000005.10(NM_024867.4): c.1645G > T (p.E549*)] in family 2, and one novel homozygous missense variant [NC_000005.10(NM_024867.4): c.2524G > A (p.D842N)] in family 3. All the patients presented with male infertility and PCD/likely PCD. All variants were present at very low levels in public databases, predicted to be deleterious in silico prediction tools, and were further confirmed deleterious by in vitro analyses. Ultrastructural analyses of the spermatozoa of the patients revealed the absence of the central pair complex in the sperm flagella. Immunostaining of the spermatozoa and respiratory cilia of the patients validated the pathogenicity of the SPEF2 variants. All patients carrying SPEF2 variants underwent one ICSI cycle and delivered healthy infants. CONCLUSION: Our study reported four novel pathogenic variants of SPEF2 in three male patients with infertility and PCD/PCD-like phenotypes, which not only extend the spectrum of SPEF2 mutations but also provide information for genetic counseling and treatment of such conditions.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38581337

RESUMO

Objective: With the improvement of living standards, consumers are paying more and more attention to the quality of rice. Traditional rice quality detection relies on human sensory judgment, which is inaccurate and inefficient. With the continuous development of molecular imaging technology, more and more scholars at home and abroad have begun to pay attention to its application in the nondestructive testing of agricultural products. Molecular imaging technology combines the advantages of spectral technology and image technology, which can achieve rapid, nondestructive and accurate detection of rice quality. In this paper, taking rice as the research object, we carried out nondestructive detection research on rice varieties, moisture and starch content using molecular imaging technology. We proposed a rapid detection method based on molecular imaging technology for rice variety identification, moisture content and starch content. Molecular images of the rice samples from four origins were obtained using a molecular imaging system, the regions of interest of the rice were identified and, spectral data, textural features and morphological features of the rice were extracted. Spectral, textural and morphological features were selected by principal component analysis (PCA), and nine feature wavelengths were obtained and an optimal model was established with an accuracy of 91.67%, which demonstrated the feasibility of molecular imaging. By comparing the models, the BCC-LS-SVR model based on the RB function had the highest accuracy with R2 of 0.989, RMSEP of 0.767%, R2 of 0.985, and RMSEC of 0.591%. Moreover, starchy rice was detected using molecular imaging. The PCA-SVR model based on the RBF kernel function had the highest accuracy with R2 of 0.989, RMSEC of 0.445%, R2 of 0.991, and RMSEP of 0.669%. Our models demonstrated high accuracy in identifying rice varieties, as well as quantifying moisture and starch content, showcasing the feasibility of molecular imaging technology in rice quality assessment. This research offers a rapid, nondestructive, and accurate method for rice quality assessment, promising significant benefits for agricultural producers and consumers.

3.
Biotechnol J ; 19(1): e2300150, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37750457

RESUMO

Decellularized calfskins are a well-established skin substitute that retains the dermal tissue's spatial structure, facilitating skin regeneration, and is already available in the market. However, their mechanical properties can change with degradation, leading to tearing at the suture. Moreover, decellularized calfskins do not possess inherent antimicrobial abilities, which can lead to wound infection and further injury during the healing process. With the objectives of supporting the clinical use of decellularized calfskins, minimizing the probability of decellularized calfskin fracture and damage during usage, and improving their anti-infective properties, this study utilized a post-loading method to load gentamicin sulfate onto the decellularized calfskin to functionalize it for antimicrobial purposes. In addition, the mechanical and physicochemical properties of the drug-carrying film were investigated to see if they could meet the clinical requirements. The results revealed that vancomycin sulfate could be loaded onto the decellularized calfskin without affecting collagen. The tensile strength of the drug-loaded membrane was determined to be in the range of 5.53-29.25 MPa, meeting the clinical requirements. Thermal analysis and pH analysis experiments demonstrated that the drug-loaded membrane did not undergo thermal denaturation or decomposition during skin repair and remained within the normal pH range of the skin, avoiding significant fluctuations in wound pH.


Assuntos
Anti-Infecciosos , Cicatrização , Biodegradação Ambiental , Pele , Antibacterianos/farmacologia
4.
Phytochemistry ; 217: 113912, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37918620

RESUMO

Artemisia argyi Levl. Et Vant, commonly known as "Chinese Mugwort," has been utilized in traditional Chinese medicine and cuisine for centuries. Aged Chinese Mugwort has been uncovered to possess superior quality and safety, and its ethyl acetate extract has been found to exhibit anti-hepatitis B virus (HBV) activity. In this study, twenty-five sesquiterpenoids were isolated and characterized from three-year-aged A. argyi. Among them, 14 previously undescribed sesquiterpenoids (1-14), featuring double bond oxidation or ring opening. It is hypothesized that during the aging process, sesquiterpenes undergo oxidative transformation of their double bonds to form alcohols due to external factors and inherent properties. The anti-HBV activity and cytotoxicity of all compounds were assessed in vitro using HepG 2.2.15 cells, and their structure-activity relationships were analyzed through three-dimensional quantitative structure-activity relationship (3D-QASR) techniques. The α-methylene-γ-lactone sesquiterpenoid derivatives were discovered to have potent inhibitory activity against HBV. This research may broaden the potential applications of Chinese Mugwort and offer further guidance for its development and utilization as functional food or traditional Chinese medicine.


Assuntos
Artemisia , Sesquiterpenos , Vírus da Hepatite B , Relação Quantitativa Estrutura-Atividade , Artemisia/química , Medicina Tradicional Chinesa , Sesquiterpenos/farmacologia
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 303: 123189, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37506455

RESUMO

In recent years, the excessive use of pesticides has posed significant hazards to the ecological environment and human health in the pursuit of high crop yields. In this work, we developed a simple, sensitive, and eco-friendly approach for rapid detection of thiabendazole in apple juice using surface-enhanced Raman scattering (SERS) coupled with silver-coated gold nanoparticles (Au@Ag NPs). The developed Au@Ag NPs exhibited excellent sensitivity, allowing for the detection of thiabendazole in standard solutions at a minimum concentration of 50 ng/mL. Furthermore, two sample preparation methods were compared for detecting thiabendazole in apple juice. As the direct detection method for SERS analysis failed to detect thiabendazole at levels below the maximum residue limit based on the Chinese standard (3000 ng/mL), the effects of main matrix components in apple juice on the detection of thiabendazole were further investigated. The results revealed that both sugars and organic acids in apple juice interfered with the SERS measurement to varying degrees. Consequently, we optimized the QuEChERS method for sample preparation and achieved a higher sensitivity with a minimum detectable concentration of 250 ng/mL, a limit of detection of 0.06 mg/L and the recoveries of spiked samples were ranged from 80.2 % to 108.6 %. This study demonstrated the feasibility of proposed SERS method for pesticide residue analysis, addressing the need for food safety monitoring.


Assuntos
Malus , Nanopartículas Metálicas , Humanos , Malus/química , Ouro/química , Tiabendazol/análise , Prata/química , Análise Espectral Raman/métodos , Contaminação de Alimentos/análise , Nanopartículas Metálicas/química
6.
Odontology ; 111(4): 813-829, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37402971

RESUMO

Titanium and its alloys are the preferred materials for medical implants. However, easy infection is a fatal shortcoming of Ti implants. Fortunately, the ongoing development of antibacterial implant materials is a promising solution, and Ti alloys with antibacterial properties hold immense potential for medical applications. In this review, we briefly outline the mechanisms of bacterial colonization and biofilm formation on implants; discuss and classify the major antimicrobials currently in use and development, including inorganic and organic antimicrobials; and describe the important role of antimicrobials in the development of implant materials for clinical applications. Strategies and challenges related to improving the antimicrobial properties of implant materials as well as the prospects of antibacterial Ti alloys in the medical field are also discussed.


Assuntos
Implantes Dentários , Titânio , Titânio/farmacologia , Ligas/farmacologia , Teste de Materiais , Staphylococcus aureus , Antibacterianos/farmacologia , Materiais Dentários , Propriedades de Superfície
7.
Wien Klin Wochenschr ; 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37256422

RESUMO

The well-known impact of ovarian endometriosis on female quality of life and the established role of lncRNA LINC01465 in ovarian cancer pathogenesis have been extensively documented; however, the relationship between LINC01465 and ovarian endometriosis is still not clear. This study seeks to explore the potential involvement of LINC01465 in the disease. The study analyzed a sample of 80 endometriosis patients and 80 healthy women. The expression of LINC01465 was measured in ectopic and eutopic endometrial tissues through RT-qPCR. The diagnostic potential of serum LINC01465 levels was evaluated using ROC curve analysis, and the patients were followed up for 3 years after treatment to monitor recurrence. The results revealed that the expression of LINC01465 was significantly lower in ectopic endometrial tissues in comparison to paired eutopic tissues for most of the patients. No correlation was found between the patient's age or lifestyle and serum LINC01465 levels. After treatment, the serum LINC01465 level increased, and patients who experienced recurrence had significantly lower levels compared to those who did not. In conclusion, the study findings suggest that the downregulation of LINC01465 plays a role in the pathogenesis of ovarian endometriosis and may serve as a diagnostic and prognostic biomarker for the disease.

8.
Arch Virol ; 168(4): 112, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918497

RESUMO

In this study, rectal samples collected from 60 stray dogs in dog shelters were screened for canine kobuvirus and other enteroviruses by quantitative real-time reverse transcription polymerase chain reaction. Canine kobuvirus was detected in 25% (15/60) of the samples. In the 15 positive samples, the coinfection rates of canine distemper virus, canine coronavirus, canine astrovirus, canine norovirus, and canine rotavirus were 26.67%, 20.00%, 73.33%, 0%, and 20.00%, respectively. Phylogenetic analysis based on partial VP1 sequences identified a novel canine kobuvirus that was a recombinant of canine and feline kobuvirus. Bayesian evolutionary analysis revealed that the rate of evolution of the VP1 gene of canine kobuvirus was 1.36 × 10-4 substitutions per site per year (95% highest posterior density interval, 6.28 × 10-7 - 4.30 × 10-4 substitutions per site per year). Finally, the divergence time of VP1 was around 19.44 years ago (95% highest posterior density interval, 12.96-27.57 years).


Assuntos
Doenças do Gato , Doenças do Cão , Kobuvirus , Infecções por Picornaviridae , Cães , Animais , Gatos , Kobuvirus/genética , Filogenia , Teorema de Bayes , China/epidemiologia , Fezes
9.
ACS Appl Bio Mater ; 5(12): 5826-5831, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36441583

RESUMO

It is necessary to develop reliable chemiluminescence strategies for determination of intracellular adenosine triphosphate (ATP), which is vital in life science and clinical diagnosis. However, the current chemiluminescence methods based on firefly luciferase suffered from low delivery efficiency, unsatisfied targeting performance, and autohydrolysis in living biosystem. To circumvent these drawbacks, a thermoresponsive polymer nanocomposite modified with firefly luciferase and ATP aptamer (PFLNC@aptamer) was fabricated, which targeted ATP and determined the intracellular ATP levels via measuring the chemiluminescence signals at different temperatures. The PFLNC@aptamer exhibited capability for the enzymolysis efficiency regulation, increased 21.0% with temperature change from 37.0 to 25.0 °C. The ATP detection limit was 3.3 nM with a linear relationship from 10.0 nM to 0.1 mM. Moreover, the thermoresponsive nanocomposite could also effectively avoid the interference during delivering firefly luciferase into the living cells and effectively discriminate ATP via the immobilized ATP aptamer, which further confirmed its reliability for practical applications. It paves a specific avenue for effective intracellular ATP monitoring in fundamental and applied research.


Assuntos
Trifosfato de Adenosina , Nanocompostos , Luciferases de Vaga-Lume , Polímeros , Reprodutibilidade dos Testes
10.
J Environ Manage ; 324: 116300, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36174467

RESUMO

Microbially induced carbonate precipitation (MICP) technology is difficult to be used for phosphogypsum (PG) treatment because the pH of PG is too low to be suitable for the growth of some bacteria. When acidophilus bacteria are used to treat PG, their low mineralization rate leads to low removal of the impurities. Based on the above problems, this study reports a new method that uses enzyme induced carbonate precipitation (EICP) modified acidophilus bacteria solution to remove phosphorus (P) and fluorine (F) in PG. Five kinds of mixtures of MICP and EICP (ME) were used to leach the PG column, and its mechanism was discussed. The results show that when the ratio of MICP to EICP is 2:1, the removal ratio of P and F is the highest, which reaches 72.87-74.92%. Compared with the single traditional bacillus solution or single acidophilic bacteria solution, the impurity removal ratio of the ME21 (MICP:EICP=2:1) mixture is increased by about 13%. The good acid resistance of the urease enzyme and acidophilic bacteria improves their growth and activity, thus increasing the biomineralization rate by about 22%. Additionally, the ME treatment is 30% cheaper than the traditional binder treatment. Therefore, this new treatment is a low-cost and environmentally friendly method.


Assuntos
Carbonato de Cálcio , Flúor , Fósforo , Carbonatos , Bactérias , Fluoretos , Precipitação Química
11.
Sensors (Basel) ; 22(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36015965

RESUMO

Monocular 3D object detection is very challenging in autonomous driving due to the lack of depth information. This paper proposes a one-stage monocular 3D object detection network (MDS Net), which uses the anchor-free method to detect 3D objects in a per-pixel prediction. Firstly, a novel depth-based stratification structure is developed to improve the network's ability of depth prediction, which exploits the mathematical relationship between the size and the depth in the image of an object based on the pinhole model. Secondly, a new angle loss function is developed to further improve both the accuracy of the angle prediction and the convergence speed of training. An optimized Soft-NMS is finally applied in the post-processing stage to adjust the confidence score of the candidate boxes. Experiment results on the KITTI benchmark demonstrate that the proposed MDS-Net outperforms the existing monocular 3D detection methods in both tasks of 3D detection and BEV detection while fulfilling real-time requirements.

12.
Anal Chem ; 93(44): 14743-14747, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34709796

RESUMO

A long-standing challenge has been the simultaneous sensing of intracellular temperature and norepinephrine (NE) variations to explore signaling pathways and depression pathogeny. Here, we designed a fluorescent probe using poly(N-isopropylacrylamide) and 1-[4-(7-nitro-benzo [1,2,5]oxadiazol-4-yl)-piperazin-1-yl]-propenone (PNIPAm-AANBD) and (E)-1-(4-boronobenzyl)-2-(2-(1,3-dioxo-1H,3H-benzo[de]isochromen-6-yl)vinyl)pyridin-1-ium bromide (PHE) for simultaneously measuring the temperature and NE with high selectivity. The fluorescence intensity of the PNIPAm-AANBD moiety exhibited a good response to temperature changes. The PHE moiety could selectively sense NE due to the naphthalic anhydride group in PHE, which formed naphthalimide upon bonding with the primary amino group of NE. The hydroxyl-terminated ligand recognized the phenolic hydroxyl group of NE through the formation of hydrogen bonds. Using the proposed fluorescent probe, variations in the intracellular temperature and NE during NE reuptake could be simultaneously measured. It was first discovered that with the inhibition of antidepressant drugs, the intracellular temperature increased by 1.2-2.1 °C, and the NE reuptake decreased by about 21.5 µM. The measured variations in intracellular temperature and NE during neurotransmitter reuptake can shed light on the underlying mechanism of neurotransmitter signaling pathways, which may facilitate the treatment of depression.


Assuntos
Corantes Fluorescentes , Norepinefrina , Antidepressivos , Naftalimidas , Temperatura
13.
Huan Jing Ke Xue ; 42(7): 3348-3357, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212660

RESUMO

Protein-like dissolved organic matter (pDOM), which is ubiquitous in natural waters, is a critical precursor of nitrogenous disinfection byproducts. Recently, the control and elimination of pDOM have been a growing concern during drinking water treatment processes. In this study, a high-performance size exclusion chromatography system coupled with photo-diode array, fluorescence detector, and online organic carbon detector (HPSEC-PDA/FLD/OCD) was used to determine the removal behaviors of different-sized pDOM from two full-scale drinking water treatment plants (DWTPs). Coagulation and activated carbon adsorption were selected for bench-scale experiments to further assess the removal behavior of pDOM during conventional water treatment processes. The results showed that different-sized pDOM fractions exhibited different removal characteristics. Pre-oxidation can effectively remove some tyrosine-like and tryptophan-like components with high MW, and as the oxidization effect was enhanced, more high MW fractions decomposed into low MW ones. Conversely, some aliphatic pDOM fractions in high MW (e.g., aliphatic proteins) were not subject to pre-oxidation removal. The coagulation-sedimentation unit was efficient in removing high MW fractions, specifically tryptophan-like fractions. Additionally, some pDOM components may be released during coagulation. pDOM with low MW and high hydrophobicity were easily removed during activated carbon filtration. However, long-term operation of the activated carbon filter may breed microorganisms, resulting in the partial release of pDOM fractions. Moreover, UV disinfection processes promoted the degradation of low MW pDOM components. Due to the complex water quality and uncontrollable microbial activities, the aforementioned water treatment units did not exhibit a synergistic effect on pDOM removal. In comparison with humic-like substances, pDOM was susceptible to water quality changes, and its removal was limited in the surveyed DWTPs. Therefore, DWTPs must strengthen pDOM monitoring in influent and effluent and adjust the operating parameters of different treatment units in a timely manner. Moreover, the combination of advanced water treatment processes, such as ozone-biological activated carbon process and nanofiltration, should also be considered to strictly control pDOM component removal.


Assuntos
Água Potável , Poluentes Químicos da Água , Purificação da Água , Carvão Vegetal , Filtração , Compostos Orgânicos/análise , Poluentes Químicos da Água/análise
14.
Pest Manag Sci ; 77(11): 5278-5285, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34302708

RESUMO

BACKGROUND: The purpose of this study was to use folic acid and zinc nitrate to construct a biocompatible supramolecular hydrogel loaded with the herbicide dicamba as an ultra-low-volume spray formulation. The drift potential of the hydrogel was studied by simulating the field environment in a wind tunnel. RESULTS: The three-dimensional network structure of the successfully prepared dicamba hydrogel system was observed using cryo-scanning electron microscopy. A rheological study of the dicamba hydrogel showed that it has shear-thinning and self-healing properties. Using a laser particle size analyzer, it was shown that the droplet size of the dicamba gel (approximately 100 µm) was significantly larger than that of the control group water and dicamba-KOH droplets. Droplet collectors and water-sensitive papers were arranged in the wind tunnel to evaluate the drift-reduction performance of the dicamba gel. Compared with dicamba-KOH aqueous solution, dicamba gel has a good effect in reducing drift. CONCLUSION: This hydrogel containing no organic solvents showed biocompatibility and biodegradability due to its natural and readily available raw materials. The main way in which hydrogels reduce drift is by increasing the droplet size and this is due to the three-dimensional network structure inside the gel. This research provides a new strategy to reduce spray drift from the perspective of pesticide formulation, and also has prospects for the application of supramolecular hydrogels in agriculture.


Assuntos
Praguicidas , Agricultura , Ácido Fólico , Hidrogéis , Tamanho da Partícula , Praguicidas/análise , Zinco
15.
Anal Chem ; 93(19): 7317-7322, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33949860

RESUMO

Sialic acid (SA) is an important monosaccharide that is involved in incurable cancer immunotherapy. However, it is difficult to detect SA in situ using the existing strategy based on the SA-terminated glycopeptide extraction from the cell lysate. The countermeasures of the bottleneck caused by cell disruption and peptide extraction should be designed based on a "cell-surface attachment and controlled enzymolysis" protocol. Herein, a poly(styrene-co-maleic anhydride-acrylic acid-concanavalin A) (PSM-PAA-ConA) was synthesized and developed as a pH-regulated enzyme nanoreactor after being loaded with sialidase and myoglobin. The nanoreactor showed controllable biocatalysis induced by a cascade enzyme reaction and applied for the in situ detection of SA on a living cell surface. The addition of an acidic solution resulted in a decrease in the size of the nanoreactor and enhancement of its permeability, triggering an "on" state of the SA catalysis. Subsequent pH increase led to increased hydrophilicity of the nanoreactor, increasing its size and resulting in the catalytic "off" state. ConA assisted the cell-surface attachment of the enzyme reactor. Furthermore, SA on the surface of living cancer cells was successfully monitored by the pH-regulated enzyme nanoreactor, demonstrating the feasibility of high specificity in situ analysis for SA. This pH-induced catalytic efficiency control by the enzyme nanoreactor provides a potential platform for functional stimuli-responsive catalytic systems as well as a strategy for in situ analysis of biomolecules on the cell surface.


Assuntos
Ácido N-Acetilneuramínico , Polímeros , Concentração de Íons de Hidrogênio , Imunoterapia , Nanotecnologia
16.
Anal Bioanal Chem ; 413(4): 979-985, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33200243

RESUMO

The use of nanomaterials as mimic enzymes provides a promising way to implement bio-molecule detection in living systems. However, to achieve highly efficient catalytic processes with gold nanocluster-based nanozymes is still challenging. In this study, a facile reduction method was utilized to synthesize gold nanoclusters with 1-methyl-D-tryptophan as the reducing and capping agent. The obtained gold nanoclusters exhibited a peroxidase-mimicking property in the redox reaction of 3,3',5,5'-tetramethylbenzidine to blue oxidized 3,3',5,5'-tetramethylbenzidine in the presence of H2O2. The addition of norfloxacin endowed the nanozymes with a 10-fold enhancement in catalytic efficiency due to the surface charge-controlled electron transfer modulation. The colorimetric sensing system presented a high selectivity toward norfloxacin. The good linear relationship of norfloxacin monitoring was gained in the range of 1.25~8.0 µM (R2 = 0.996), with a detection limit of 0.2 µM. The practical application of the proposed protocol for the measurement of norfloxacin in capsules was realized. This demonstrates that on account of their significant catalytic efficiency enhancement, the gold nanocluster-based nanozymes hold great promise in realizing the selective detection of drugs. Graphical Abstract.


Assuntos
Antibacterianos/análise , Ouro/química , Nanopartículas Metálicas/química , Norfloxacino/análise , Benzidinas/química , Cápsulas , Catálise , Colorimetria/métodos , Peróxido de Hidrogênio/química , Limite de Detecção , Nanopartículas Metálicas/ultraestrutura , Oxirredução , Peroxidase/química
17.
Analyst ; 145(10): 3564-3568, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32307504

RESUMO

Gold nanoclusters (AuNCs) have emerged as a new generation of "nanozymes" based on their intrinsic catalytic activity. However, highly selective and colorimetric detection of drugs is still far from adequately developed due to the lack of means of regulating the catalytic activity of nanozymes. Herein, d-histidine stabilized AuNCs (d-His@AuNCs) were synthesized and their nanozyme ability was demonstrated in the catalytic oxidation of the peroxidase substrate, 3,3',5,5'-tetramethylbenzidine, for the promotion of hydrogen peroxide. Copper ions led to the aggregation of d-His@AuNCs and inhibited their peroxidase-like activity. The addition of doxycycline restored the enzyme-mimicking catalytic activity of d-His@AuNCs, which was based on the strong coordination interaction between copper ions and doxycycline. A highly sensitive and colorimetric assay for determining the amount of doxycycline was developed at a detection wavelength of 650 nm. The color intensity and ultraviolet-visible absorbance intensity of the testing assay displayed a good linear relationship in the doxycycline concentration range of 5.0-12.5 µM, with a limit of detection of 1.0 µM. Moreover, the metabolic process of doxycycline in serum was further investigated with the proposed monitoring system after the drug was abdominally injected into rats. Notably, the tunable catalytic activity performance of the nanozymes indicates their significant potential in clinical application.


Assuntos
Materiais Biomiméticos/química , Análise Química do Sangue/métodos , Colorimetria/métodos , Doxiciclina/sangue , Ouro/química , Histidina/química , Nanoestruturas/química , Peroxidase/metabolismo , Catálise
18.
ChemistryOpen ; 7(12): 977-983, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30524923

RESUMO

Some N-tosylhydrazone derivatives were effectively synthesized under solvent-free conditions by using a grinding method at room temperature. The short reaction time, clean and mild process with simple workup and easy purification of the target compounds were salient features of the present protocol, which enables straightforward access to N-tosylhydrazones. Among the tosylhydrazone derivatives evaluated, compound 3 l exhibits excellent apoptosis-promoting and anticancer potential against triple-negative breast cancer (TNBC) cell lines. This research shows that our synthesized compound 3 l may be a desirable and effective therapeutic drug against TNBC.

19.
Soft Matter ; 14(39): 8030-8035, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30246851

RESUMO

The relationship between adhesion force and the height drops containing difenoconazole-loaded mesoporous silica nanoparticles (DF-MSNs)/Tween 80 bounce on cabbage leaf surfaces was investigated as a function of Tween 80 concentration. The adhesion force of a pesticide droplet on cabbage leaf surfaces was assessed using a high-sensitivity microelectromechanical balance system and the impact behavior was recorded with a high-speed camera. The height droplets bounced decreased with increasing adhesion force, with a negative correlation between the height of the bouncing drops and adhesion force. Although droplets containing ≥0.06% Tween 80 adhered to the cabbage leaves, the retraction height was still observed to decrease as the adhesion force increased. The experimental results indicate that for cabbage leaf surfaces, the adhesion force has a significant effect on the height drops bounce. The results provide new insights into how researchers can screen for formulations for hydrophobic target crops and how to increase spray adhesion to difficult-to-wet crop leaf surfaces.

20.
J Am Chem Soc ; 138(21): 6805-12, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27195582

RESUMO

Condensation reactions such as Guerbet and aldol are important since they allow for C-C bond formation and give higher molecular weight oxygenates. An initial study identified Pd-supported on hydrotalcite as an active catalyst for the transformation, although this catalyst showed extensive undesirable decarbonylation. A catalyst containing Pd and Cu in a 3:1 ratio dramatically decreased decarbonylation, while preserving the high catalytic rates seen with Pd-based catalysts. A combination of XRD, EXAFS, TEM, and CO chemisorption and TPD revealed the formation of CuPd bimetallic nanoparticles with a Cu-enriched surface. Finally, density functional theory studies suggest that the surface segregation of Cu atoms in the bimetallic alloy catalyst produces Cu sites with increased reactivity, while the Pd sites responsible for unselective decarbonylation pathways are selectively poisoned by CO.

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