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1.
Artigo em Inglês | MEDLINE | ID: mdl-38522713

RESUMO

Statins, widely prescribed for cholesterol management by inhibiting HMG-CoA reductase in the cholesterol biosynthesis pathway, may also influence vertebrate development. In this study, we investigated the developmental effects of two widely used statins, atorvastatin (ATO) and pravastatin (PRA), on zebrafish offspring. For ATO, we administered doses classified as low (1 µM), medium (5 µM), and high (10 µM), while for PRA, the corresponding concentrations were set at low (18 µM), medium (180 µM), and high (270 µM). Our results showed significant reductions in birth and hatching rates, along with decreased body length in offspring at all ATO concentrations and medium to high PRA concentrations. A notable increase in malformation rates, especially in the spine and heart, was observed across all ATO treatments and in medium and high PRA groups. Additionally, we observed reduced heart contraction rates, decreased heart size, lower bone volumes, and diminished expression of mRNA osteogenic markers. Elevated venous sinus-artery bulb (SV-BA) ratios, increased thoracic area, and abnormal cartilage development were also prominent in all ATO-treated groups. Transcriptome analysis revealed alterations in genes predominantly associated with ion channels. These findings provide insights into the potential impacts of specific concentrations of statins on offspring development and highlight potential gene interactions with statins.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Animais , Inibidores de Hidroximetilglutaril-CoA Redutases/toxicidade , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Peixe-Zebra/genética , Transcriptoma , Pravastatina/farmacologia , Pravastatina/uso terapêutico , Atorvastatina/toxicidade , Canais Iônicos
2.
Adv Mater ; 36(16): e2313155, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38228320

RESUMO

The electrosynthesis of nitrate catalyzed by electrochemical nitrogen oxidation reaction (NOR) is considered as an alternative and sustainable approach to the conventional industrial manufacture, but optimizing the electrocatalytic NOR performance and fabricating the efficient NOR electrocatalysts at the design level still encounter great challenges. Herein, unique Pd2+- and S2--doped TiO2 (Pb/S-TiO2) nanoparticles are successfully in situ grown on the surface of 2-methylimidazolium-functionalized polypyrrole/graphene oxide (2-MeIm/PPy/GO), which present the typical hierarchical micro-nanostructures, resulting in the excellent electrocatalytic NOR performance with the highest NO3 - yield of 72.69 µg h-1 mg-1 act. and the maximum Faraday efficiency of 8.92% at 2.04 V (vs reversible hydrogen electrode) due to the synergistic effect of each component. Due to the doping effect, the appropriate oxygen evolution reaction (OER) activity is achieved by Ti-site, where OER principally occurs, providing *O during the non-electrochemical step of NOR, while the electrocatalytic NOR process as the electrochemical conversion of inert N2 to active *NO intermediates mainly occurs at the Pd-site. Especially, the sulfate radicals in situ formed on Pb/S-TiO2@2-MeIm/PPy/GO further promote nitrogen adsorption and decrease the reaction energy barrier, resulting in the acceleration of NOR. It provides theoretical and practical experience for the design and preparation of NOR electrocatalysts.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 308: 123748, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38091651

RESUMO

Herein, blue-emitting gold nanoclusters (Au NCs) were carried out through tryptophan as the protecting and reducing agents. In aqueous solution of Au NCs@tryptophan, the addition of furaltadone guaranteed the interaction of furaltadone with tryptophan around Au NCs. The propinquity of furaltadone to Au NCs caused that the fluorescence of Au NCs was weakened by furaltadone based on the inner filter effect (IFE). Under the optimal measurement conditions, the logarithm of relative fluorescence intensity of Au NCs@tryptophan was linearly carried out with the furaltadone amount increasing from 0.5 to 100 µM, the corresponding detection limit was 0.087 µM. The fluorescence change of Au NCs@tryptophan displayed excellent selectivity and sensitivity for furaltadone than other possible substance in the human body. In view of Au NCs@tryptophan, the as-performed fluorescence nanosensor suggested outstanding ability for furaltadone sensing in real samples. Obviously, this nanoprobe of furaltadone could implement the naked-eye visual fluorescence determination of furaltadone.


Assuntos
Nanopartículas Metálicas , Nitrofuranos , Oxazolidinonas , Triptofano , Humanos , Espectrometria de Fluorescência/métodos , Ouro , Corantes Fluorescentes
4.
Nanomicro Lett ; 16(1): 27, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37989893

RESUMO

Lithium-oxygen battery with ultra-high theoretical energy density is considered a highly competitive next-generation energy storage device, but its practical application is severely hindered by issues such as difficult decomposition of discharge products at present. Here, we have developed N-doped carbon anchored atomically dispersed Ru sites cathode catalyst with open hollow structure (h-RuNC) for Lithium-oxygen battery. On one hand, the abundance of atomically dispersed Ru sites can effectively catalyze the formation and decomposition of discharge products, thereby greatly enhancing the redox kinetics. On the other hand, the open hollow structure not only enhances the mass activity of atomically dispersed Ru sites but also improves the diffusion efficiency of catalytic molecules. Therefore, the excellent activity from atomically dispersed Ru sites and the enhanced diffusion from open hollow structure respectively improve the redox kinetics and cycling stability, ultimately achieving a high-performance lithium-oxygen battery.

5.
Opt Lett ; 48(18): 4865-4868, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37707923

RESUMO

Herein, we demonstrate the generation of optical vortex arrays pulses using a Sagnac common-path interferometric vortex generator. Hermite-Gaussian (HG) modes with different orders are initially obtained from a SESAM mode-locked laser in the positive dispersion regime. Then, in the interferometric vortex generator, by controlling the phase difference and sheering displacement between two HG modes, optical vortex pulses with different numbers of phase singularities are generated through superposition. The generated HG10 mode has a pulse width of 2 ps and maximum energy of 0.75 nJ. One-dimensional vortex arrays and triangular vortex arrays are also generated, which are formed by HGm0 and HG0n modes, respectively. This work has potential applications in the massive manipulation of microparticles, optical communication, and so on.

6.
Nano Lett ; 23(19): 9119-9125, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37773017

RESUMO

The discharge product Li2O2 is difficult to decompose in lithium-oxygen batteries, resulting in poor reversibility and cycling stability of the battery, and the morphology of Li2O2 has a great influence on its decomposition during the charging process. Therefore, reasonable design of the catalyst structure to improve the density of catalyst active sites and make Li2O2 form a morphology which is easy to decompose in the charging process will help improve the performance of battery. Here, we demonstrate a series of hollow nanoboxes stacked by Co3O4 nanoparticles with different sizes. The results show that the surface of the nanoboxes composed of smaller size Co3O4 nanoparticles contains abundant pore structure and higher concentration of oxygen vacancies, which changes the adsorption energy of reactants and intermediates, providing more nucleation sites for Li2O2, thereby forming Li2O2 with high dispersion, which is easier to decompose during charging, and eventually improve the performance of the battery. This provides an important idea for the structural design of the cathode catalyst in lithium-oxygen batteries and the regulation of Li2O2 morphology.

7.
Opt Lett ; 48(10): 2692-2695, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37186742

RESUMO

The demand for high-dimensional encoding techniques for communication systems is increasing. Vortex beams carrying orbital angular momentum (OAM) provide new degrees of freedom for optical communication. In this study, we propose an approach for increasing the channel capacity of free-space optical communication systems by integrating superimposed orbital angular momentum (OAM) states and deep learning techniques. We generate composite vortex beams with topological charges ranging from -4 to 8 and radial coefficients ranging from 0 to 3. A phase difference among each OAM state is introduced to significantly increase the number of available superimposed states, achieving up to 1024-ary codes with distinct features. To accurately decode the high-dimensional codes, we propose a two-step convolutional neural network (CNN). The first step is to make a coarse classification of the codes, while the second step is to finely identify the code and achieve decoding. Our proposed method demonstrates 100% accuracy achieved for the coarse classification after 7 epochs, 100% accuracy achieved for the fine identification after 12 epochs, and 99.84% accuracy achieved for testing, which is much faster and more accurate than one-step decoding. To demonstrate the feasibility of our method, we successfully transmitted a 24-bit true-color Peppers image once with a resolution of 64 × 64 in the laboratory, yielding a bit error rate of 0.

8.
Stem Cell Reports ; 18(3): 706-719, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36827976

RESUMO

Loss of function (LoF) of TAR-DNA binding protein 43 (TDP-43) and mis-localization, together with TDP-43-positive and hyperphosphorylated inclusions, are found in post-mortem tissue of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) patients, including those carrying LoF variants in the progranulin gene (GRN). Modeling TDP-43 pathology has been challenging in vivo and in vitro. We present a three-dimensional induced pluripotent stem cell (iPSC)-derived paradigm-mature brain organoids (mbOrg)-composed of cortical-like-astrocytes (iA) and neurons. When devoid of GRN, mbOrgs spontaneously recapitulate TDP-43 mis-localization, hyperphosphorylation, and LoF phenotypes. Mixing and matching genotypes in mbOrgs showed that GRN-/- iA are drivers for TDP-43 pathology. Finally, we rescued TDP-43 LoF by adding exogenous progranulin, demonstrating a link between TDP-43 LoF and progranulin expression. In conclusion, we present an iPSC-derived platform that shows striking features of human TDP-43 proteinopathy and provides a tool for the mechanistic modeling of TDP-43 pathology and patient-tailored therapeutic screening for FTD and ALS.


Assuntos
Esclerose Amiotrófica Lateral , Demência Frontotemporal , Humanos , Esclerose Amiotrófica Lateral/patologia , Demência Frontotemporal/genética , Granulinas/genética , Granulinas/metabolismo , Progranulinas/genética , Progranulinas/metabolismo , Astrócitos/metabolismo , Mutação , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Encéfalo/metabolismo
10.
Opt Express ; 30(26): 46888-46899, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558629

RESUMO

Focusing light through scattering media is essential for high-resolution optical imaging and deep penetration. Here, a two-step focusing method based on neural networks (NNs) and multi-pixel coding is proposed to achieve high-quality focusing with theoretical maximum enhancement. In the first step, a single-layer neural network (SLNN) is used to obtain the initial mask, which can be used to focus with a moderate enhancement. In the second step, we use multi-pixel coding to encode the initial mask. The coded masks and their corresponding speckle patterns are used to train another SLNN to get the final mask and achieve high-quality focusing. In this experiment, for a mask of 16 × 16 modulation units, in the case of using 8 pixels in a modulation unit, focus with the enhancement of 40.3 (only 0.44 less than the theoretical value) has been achieved with 3000 pictures (1000 pictures in the first step and 2000 pictures in the second step). Compared with the case of employing only the initial mask and the direct multi-pixel encoded mask, the enhancement is increased by 220% and 24%. The proposed method provides a new idea for improving the focusing effect through the scattering media using NNs.

11.
Opt Express ; 30(18): 31998-32009, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36242270

RESUMO

Noise-like pulses (NLP) are extremely sought after in low-coherence tomography and supercontinuum, etc. Here, we propose an effective method to form the NLP in the all-normal-dispersion (ANDi) fiber laser by weakening the spectrum filtering for the first time. Numerical explorations are performed in detail and demonstrate that the NLP can be originated from the clustering behavior of amplified random sub-pulses led by the saturable absorber. By simulating the pulse-pattern distribution in the two-dimensional parameter space, it is further found that this kind of NLP pattern is widely distributed where are with a weak spectrum filtering. Since, the weaker the filtering, the harder the dissipative system to achieve balance, which helps to avoid the evolution from the pulse cluster to other coherent states and supports the NLP stability. To prove the feasibility experimentally, we built an ANDi fiber laser based on the nonlinear polarization rotating (NPR). The built laser can operate at the stable dissipative soliton (DS) state with a spectrum filter, which also with a 45 nm wavelength tuning performance. Replacing the filter, only NLP with a 40.2 ps pedestal and 237 fs spike can be attained. The experiments agree well with the numerical predictions. This exploration significantly broadens the design possibilities for ultrafast lasers, making them much more accessible to produce desired pulse patterns.

12.
Opt Lett ; 47(3): 521-524, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103666

RESUMO

Flat-top beams have plenty of applications in theoretical and applied research, but they are not eigenmodes of the wave equation. Here, we propose an effective strategy for generating flat-top beams in fibers, which originates from the incoherent superposition of orbital angular momentum (OAM) and fundamental (LP01) modes. The designed all-fiber passively Q-switched laser can realize high-quality pulsed flat-top and OAM beam emissions. The normalized root mean square of the flat-top beam is around 4.7%, and the purity of the OAM mode is calculated to be higher than 98%. For the first time to the best of our knowledge, pulsed emission of a flat-top beam is achieved using an all-fiber laser. Moreover, its repetition rate and duration can be controlled by adjusting the pump.

13.
Methods Mol Biol ; 2417: 121-130, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35099796

RESUMO

Many biochemical and biophysical related questions require the isolation of functional synaptic vesicles. Isolated synaptic vesicles can be used for transporter kinetics studies, synaptic vesicle content analysis and immuno-labeling of specific synaptic vesicle proteins, etc. Here I describe a fast and reliable isolation procedure to allow researchers to isolate a large amount, as well as physiologically functional synaptic vesicles, by following the subsequent order of cryogrinding, gradient ultracentrifugation, and size exclusion liquid chromatography. This process enriches over 90% of the synaptic vesicle population, with low contamination of Golgi or endoplasmic reticulum vesicles.


Assuntos
Complexo de Golgi , Vesículas Sinápticas , Cromatografia em Gel , Complexo de Golgi/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Vesículas Sinápticas/metabolismo , Ultracentrifugação
14.
J Biol Chem ; 298(3): 101587, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35032550

RESUMO

Catabolite control protein A (CcpA) of the human pathogen Staphylococcus aureus is an essential DNA regulator for carbon catabolite repression and virulence, which facilitates bacterial survival and adaptation to a changing environment. Here, we report that copper (II) signaling mediates the DNA-binding capability of CcpA in vitro and in vivo. Copper (II) catalyzes the oxidation of two cysteine residues (Cys216 and Cys242) in CcpA to form intermolecular disulfide bonds between two CcpA dimers, which results in the formation and dissociation of a CcpA tetramer of CcpA from its cognate DNA promoter. We further demonstrate that the two cysteine residues on CcpA are important for S. aureus to resist host innate immunity, indicating that S. aureus CcpA senses the redox-active copper (II) ions as a natural signal to cope with environmental stress. Together, these findings reveal a novel regulatory mechanism for CcpA activity through copper (II)-mediated oxidation.


Assuntos
Proteínas de Bactérias , Cobre , DNA Bacteriano , Proteínas Repressoras , Staphylococcus aureus , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Cátions Bivalentes , Cobre/química , Cobre/metabolismo , Cisteína/química , Cisteína/metabolismo , DNA Bacteriano/metabolismo , Oxirredução , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo , Staphylococcus aureus/metabolismo
15.
Chemistry ; 27(17): 5453-5460, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33220013

RESUMO

Bacterial biofilms are a serious global health concern, often responsible for persistent infections. New strategies to prevent and treat bacterial infections by eradication of the biofilms are urgently needed. A novel ruthenium-based compound is reported in this study that functions as both a boronic acid-decorated photosensitizer (PS) and a light-triggered nitric oxide (NO) releasing agent. The compound can selectively attach to the bacterial membrane and biofilms and it is highly potent at eradicating Pseudomonas aeruginosa biofilms through the simultaneous release of NO and reactive oxygen species (ROS). The compound, which is more effective than clinical antibiotic tobramycin, also has excellent bacterial specificity and shows no significant cytotoxicity to human cells. The results reveal potential applications of this innovative dual-functional photoactivated ruthenium compound to combat bacterial biofilm infections.


Assuntos
Infecções Bacterianas , Fármacos Fotossensibilizantes , Antibacterianos/farmacologia , Infecções Bacterianas/tratamento farmacológico , Biofilmes , Humanos , Óxido Nítrico , Fármacos Fotossensibilizantes/farmacologia , Pseudomonas aeruginosa
16.
ACS Infect Dis ; 6(3): 347-354, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32027109

RESUMO

Catabolite control protein A is a highly conserved transcriptional regulator in Gram-positive bacteria. Herein, we report a specific small-molecule inhibitor of Staphylococcus aureus catabolite control protein A (SaCcpA). The compound abrogates the regulatory function of SaCcpA, resulting in decreased expression of an S. aureus major cytotoxin, α-hemolysin. The observed synergism between the compound and antibiotics against S. aureus suggests its potential application in a combination therapy to combat antimicrobial resistance.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas Repressoras/antagonistas & inibidores , Proteína Estafilocócica A/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Sinergismo Farmacológico , Proteínas Hemolisinas/genética , Relação Estrutura-Atividade
17.
Ecotoxicol Environ Saf ; 190: 110082, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31855791

RESUMO

Selenium (Se) and zinc (Zn) are two important trace elements for human being and animals. The interaction between Se and Zn on the bioavailability of Zn in soil is still unclear. Therefore, pot experiments exposed to different dosages of zinc sulfate (ZnSO4) (0, 20, and 50 mg/kg soil) and sodium selenite (Na2SeO3) (0, 0.5, 1.0, and 2.5 mg/kg soil) were conducted to investigate the effects of selenite application on Zn bioavailability in calcareous soil and its related mechanisms. The total Zn content of different tissues (roots and shoots) of pak choi (Brassica chinensis L.) and the changes in Zn fraction distribution in soil before planting and after harvest were determined, and the mobility factor (MF) and distribution index (DI) of Zn in soils were calculated. In addition, the Pearson correlation and path analysis were conducted to clarify the relationships between Zn fractions in soil and the Zn uptake of pak choi. Results showed that Se amendment elevated soil Zn bioavailability at appropriate levels of Se and Zn. When 1.0 and 2.5 mg/kg of Se and 20 mg/kg of Zn were applied in soil, the proportion of exchangeable Zn (Ex-Zn) and Zn weakly bound to organic matter (Wbo-Zn) to the total content of Zn was significantly increased by 28.14%-82.52% compared with that of the corresponding single Zn treatment. Therefore, the Zn concentration in the shoots of pak choi was significantly increased by 27.2%-31.1%. High Zn (50 mg/kg) and Se co-amended treatments showed no significantly beneficial effect on the bioavailability of Zn. In addition, the potential available Zn content in soil (weakly bound to organic matter and carbonate bound Zn) and MF and DI values were all positively correlated with the Zn concentrations in pak choi, indicating that these indexes can be used to predict the bioavailability of Zn in soil. This study can provide a good reference for Se and Zn biofortification of plants in calcareous soil.


Assuntos
Selênio/química , Poluentes do Solo/química , Zinco/química , Brassica/metabolismo , Raízes de Plantas/química , Ácido Selenioso/química , Selenito de Sódio/química , Solo , Poluentes do Solo/análise , Zinco/análise
19.
Med Sci Monit ; 24: 4510-4515, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-29959890

RESUMO

BACKGROUND The correlation between serum concentration of neuron specific enolase (NSE), S100B, and the prognosis of patients with acute spinal cord injury (ASCI) remains controversial. MATERIAL AND METHODS Sixty patients with confirmed diagnosis of ASCI were recruited for this study from February 2015 to January 2017. The serum level of NSE and S100B were dynamically measured: on the day of injury and for 2 weeks. The 60 cases were divided into Group A (1 or more than 1 ASIA grade improved at 6 months after the injury) and Group B (ASIA grades changed <1 at 6 months after the injury). The serum level of the 2 groups were compared at different time points. And the prognostic value of serum NSE and S100B as biomarkers in patients with ASCI were calculated by Bayes theorem. RESULTS The serum levels of NSE in Groups A and B on the 2nd day of injury reached a peak at 66.80±13.76 g/L and 98.87±20.12 µg/L, respectively, and then declined gradually. On the 14th day of injury, the serum levels of NSE in both groups were 21.23±8.45 and 39.32±16.31 µg/L, respectively, which were much lower than those on the 2nd day (P<0.05). The serum levels of S100B in Groups A and B rose after the injury and reached a peak on the 4th day of injury. Then, the levels declined gradually to 1.14±0.64 and 1.97±0.98 µg/L, respectively, 2 weeks after the injury. Serum levels of NSE and S100B were good biomarkers for predicting the prognosis of ASCI patients with the sensitivity of 74.35% and 71.79%, the specificity of 71.43% and 66.67%. The cutoff value for serum NSE and S100B were 29.07 µg/L and 1.67 µg/L respectively. The AUCs were 0.78 (95% CI: 0.66-0.89) and 0.76 (95% CI: 0.63-0.89) respectively for serum NSE and S100B. CONCLUSIONS Serum levels of NSE and S100B protein can reflect the degree of spinal cord injury and could be potential biomarkers for the prognosis of acute spinal cord injury.


Assuntos
Fosfopiruvato Hidratase/sangue , Subunidade beta da Proteína Ligante de Cálcio S100/sangue , Traumatismos da Medula Espinal/sangue , Doença Aguda , Adulto , Teorema de Bayes , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Traumatismos da Medula Espinal/enzimologia , Traumatismos da Medula Espinal/patologia
20.
Genom Data ; 12: 52-53, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28367405

RESUMO

Synaptic vesicles (SVs) are presynaptic organelles that load and release small molecule neurotransmitters at chemical synapses. In addition to classic neurotransmitters, we have demonstrated that SVs isolated from the Peripheral Nervous Systems (PNS) of the electric organ of Torpedo californica, a model cholinergic synapse, and SVs isolated from the Central Nervous System (CNS) of Mus musculus (mouse) contain small ribonucleic acids (sRNAs; ≤ 50 nucleotides) (Scientific Reports, 5:1-14(14918) Li et al. (2015) [1]). Our previous publication provided the five most abundant sequences associated with the T. californica SVs, and the ten most abundant sequences associated with the mouse SVs, representing 59% and 39% of the total sRNA reads sequenced, respectively). We provide here a full repository of the SV sRNAs sequenced from T. californica and the mouse deposited in the NCBI as biosamples. Three data studies are included: SVs isolated from the electric organ of T. californica using standard techniques, SVs isolated from the electric organ of T. californica using standard techniques with an additional affinity purification step, and finally, SVs isolated from the CNS of mouse. The three biosamples are available at https://www.ncbi.nlm.nih.gov/biosample/ SRS1523467, SRS1523466, and SRS1523472 respectively.

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