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1.
Cell ; 154(5): 1074-1084, 2013 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-23993097

RESUMO

Growth of prostate cancer cells is dependent upon androgen stimulation of the androgen receptor (AR). Dihydrotestosterone (DHT), the most potent androgen, is usually synthesized in the prostate from testosterone secreted by the testis. Following chemical or surgical castration, prostate cancers usually shrink owing to testosterone deprivation. However, tumors often recur, forming castration-resistant prostate cancer (CRPC). Here, we show that CRPC sometimes expresses a gain-of-stability mutation that leads to a gain-of-function in 3ß-hydroxysteroid dehydrogenase type 1 (3ßHSD1), which catalyzes the initial rate-limiting step in conversion of the adrenal-derived steroid dehydroepiandrosterone to DHT. The mutation (N367T) does not affect catalytic function, but it renders the enzyme resistant to ubiquitination and degradation, leading to profound accumulation. Whereas dehydroepiandrosterone conversion to DHT is usually very limited, expression of 367T accelerates this conversion and provides the DHT necessary to activate the AR. We suggest that 3ßHSD1 is a valid target for the treatment of CRPC.


Assuntos
3-Hidroxiesteroide Desidrogenases/genética , Di-Hidrotestosterona/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , 3-Hidroxiesteroide Desidrogenases/metabolismo , Androgênios/metabolismo , Animais , Humanos , Masculino , Camundongos , Neoplasias da Próstata/metabolismo , Proteólise , Ubiquitinação
2.
Genome Res ; 34(2): 272-285, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38479836

RESUMO

mRNA translation relies on identifying translation initiation sites (TISs) in mRNAs. Alternative TISs are prevalent across plant transcriptomes, but the mechanisms for their recognition are unclear. Using ribosome profiling and machine learning, we developed models for predicting alternative TISs in the tomato (Solanum lycopersicum). Distinct feature sets were predictive of AUG and nonAUG TISs in 5' untranslated regions and coding sequences, including a novel CU-rich sequence that promoted plant TIS activity, a translational enhancer found across dicots and monocots, and humans and viruses. Our results elucidate the mechanistic and evolutionary basis of TIS recognition, whereby cis-regulatory RNA signatures affect start site selection. The TIS prediction model provides global estimates of TISs to discover neglected protein-coding genes across plant genomes. The prevalence of cis-regulatory signatures across plant species, humans, and viruses suggests their broad and critical roles in reprogramming the translational landscape.


Assuntos
Eucariotos , Iniciação Traducional da Cadeia Peptídica , Humanos , Iniciação Traducional da Cadeia Peptídica/genética , Eucariotos/genética , Plantas/genética , Regiões 5' não Traduzidas , RNA Mensageiro/genética , Códon de Iniciação
3.
Proc Natl Acad Sci U S A ; 121(42): e2401950121, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39378086

RESUMO

Anthropogenic activities emit ~2,000 Mg y-1 of the toxic pollutant mercury (Hg) into the atmosphere, leading to long-range transport and deposition to remote ecosystems. Global anthropogenic emission inventories report increases in Northern Hemispheric (NH) Hg emissions during the last three decades, in contradiction with the observed decline in atmospheric Hg concentrations at NH measurement stations. Many factors can obscure the link between anthropogenic emissions and atmospheric Hg concentrations, including trends in the reemissions of previously released anthropogenic ("legacy") Hg, atmospheric sink variability, and spatial heterogeneity of monitoring data. Here, we assess the observed trends in gaseous elemental mercury (Hg0) in the NH and apply biogeochemical box modeling and chemical transport modeling to understand the trend drivers. Using linear mixed effects modeling of observational data from 51 stations, we find negative Hg0 trends in most NH regions, with an overall trend for 2005 to 2020 of -0.011 ± 0.006 ng m-3 y-1 (±2 SD). In contrast to existing emission inventories, our modeling analysis suggests that annual NH anthropogenic emissions must have declined by at least 140 Mg between the years 2005 and 2020 to be consistent with observed trends. Faster declines in 95th percentile Hg0 values than median values in Europe, North America, and East Asian measurement stations corroborate that the likely cause is a decline in nearby anthropogenic emissions rather than background legacy reemissions. Our results are relevant for evaluating the effectiveness of the Minamata Convention on Mercury, demonstrating that existing emission inventories are incompatible with the observed Hg0 declines.

4.
Nature ; 579(7800): 544-548, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32214266

RESUMO

Observations show robust near-surface trends in Southern Hemisphere tropospheric circulation towards the end of the twentieth century, including a poleward shift in the mid-latitude jet1,2, a positive trend in the Southern Annular Mode1,3-6 and an expansion of the Hadley cell7,8. It has been established that these trends were driven by ozone depletion in the Antarctic stratosphere due to emissions of ozone-depleting substances9-11. Here we show that these widely reported circulation trends paused, or slightly reversed, around the year 2000. Using a pattern-based detection and attribution analysis of atmospheric zonal wind, we show that the pause in circulation trends is forced by human activities, and has not occurred owing only to internal or natural variability of the climate system. Furthermore, we demonstrate that stratospheric ozone recovery, resulting from the Montreal Protocol, is the key driver of the pause. Because pre-2000 circulation trends have affected precipitation12-14, and potentially ocean circulation and salinity15-17, we anticipate that a pause in these trends will have wider impacts on the Earth system. Signatures of the effects of the Montreal Protocol and the associated stratospheric ozone recovery might therefore manifest, or have already manifested, in other aspects of the Earth system.


Assuntos
Atmosfera/química , Política Ambiental/legislação & jurisprudência , Cooperação Internacional/legislação & jurisprudência , Ozônio/análise , Vento , Regiões Antárticas , Atividades Humanas/legislação & jurisprudência , Oceanos e Mares , Chuva , Salinidade , Movimentos da Água
5.
Brief Bioinform ; 24(3)2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37088981

RESUMO

BACKGROUND: Ubiquitous presence of short extrachromosomal circular DNAs (eccDNAs) in eukaryotic cells has perplexed generations of biologists. Their widespread origins in the genome lacking apparent specificity led some studies to conclude their formation as random or near-random. Despite this, the search for specific formation of short eccDNA continues with a recent surge of interest in biomarker development. RESULTS: To shed new light on the conflicting views on short eccDNAs' randomness, here we present DeepCircle, a bioinformatics framework incorporating convolution- and attention-based neural networks to assess their predictability. Short human eccDNAs from different datasets indeed have low similarity in genomic locations, but DeepCircle successfully learned shared DNA sequence features to make accurate cross-datasets predictions (accuracy: convolution-based models: 79.65 ± 4.7%, attention-based models: 83.31 ± 4.18%). CONCLUSIONS: The excellent performance of our models shows that the intrinsic predictability of eccDNAs is encoded in the sequences across tissue origins. Our work demonstrates how the perceived lack of specificity in genomics data can be re-assessed by deep learning models to uncover unexpected similarity.


Assuntos
DNA Circular , DNA , Humanos , Genoma , Células Eucarióticas , Biomarcadores
6.
Plant Physiol ; 196(3): 1840-1856, 2024 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-39028839

RESUMO

The involvement of nuclear factor Y (NF-Y) in transcriptional reprogramming during arbuscular mycorrhizal symbiosis has been demonstrated in several plant species. However, a comprehensive picture is lacking. We showed that the spatial expression of NF-YC3 was observed in cortical cells containing arbuscules via the cis-regulatory element GCC boxes. Moreover, the NF-YC3 promoter was transactivated by the combination of CYCLOPS and autoactive calcium and calmodulin-dependent kinase (CCaMK) via GCC boxes. Knockdown of NF-YC3 significantly reduced the abundance of all intraradical fungal structures and affected arbuscule size. BCP1, SbtM1, and WRI5a, whose expression associated with NF-YC3 levels, might be downstream of NF-YC3. NF-YC3 interacted with NF-YB3a, NF-YB5c, or NF-YB3b, in yeast (Saccharomyces cerevisiae) and in planta, and interacted with NF-YA3a in yeast. Spatial expression of 3 NF-YBs was observed in all cell layers of roots under both mock and mycorrhizal conditions. Simultaneous knockdown of 3 NF-YBs, but not individually, reduced the fungal colonization level, suggesting that there might be functional redundancy of NF-YBs to regulate AM symbiosis. Collectively, our data suggest that NF-YC3 and NF-YBs positively regulate AM symbiosis in tomato, and arbuscule-related NF-YC3 may be an important downstream gene of the common symbiosis signaling pathway.


Assuntos
Fator de Ligação a CCAAT , Regulação da Expressão Gênica de Plantas , Micorrizas , Proteínas de Plantas , Solanum lycopersicum , Simbiose , Micorrizas/fisiologia , Simbiose/genética , Simbiose/fisiologia , Solanum lycopersicum/microbiologia , Solanum lycopersicum/genética , Solanum lycopersicum/fisiologia , Fator de Ligação a CCAAT/metabolismo , Fator de Ligação a CCAAT/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regiões Promotoras Genéticas/genética , Técnicas de Silenciamento de Genes , Raízes de Plantas/microbiologia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
7.
Proc Natl Acad Sci U S A ; 119(10): e2108801119, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35239440

RESUMO

SignificanceWe introduce an approach to identify latent topics in large-scale text data. Our approach integrates two prominent methods of computational text analysis: topic modeling and word embedding. We apply our approach to written narratives of violent death (e.g., suicides and homicides) in the National Violent Death Reporting System (NVDRS). Many of our topics reveal aspects of violent death not captured in existing classification schemes. We also extract gender bias in the topics themselves (e.g., a topic about long guns is particularly masculine). Our findings suggest new lines of research that could contribute to reducing suicides or homicides. Our methods are broadly applicable to text data and can unlock similar information in other administrative databases.


Assuntos
Bases de Dados Factuais , Homicídio , Modelos Teóricos , Violência , Humanos , Estados Unidos
8.
Nano Lett ; 24(38): 11847-11852, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39264273

RESUMO

The pseudomagnetic field effect may offer unique opportunities for the emergence of intriguing phenomena. To date, investigations into pseudomagnetic field effects on phonons have been limited to sound waves in metamaterials. The revelation of this exotic effect on the atomic vibration of natural materials remains elusive. Our simulations of twisted graphene nanoribbons reveal well-defined Landau spectra and sublattice polarization of phonon states, mimicking the behavior of Dirac Fermions in magnetic fields. Both valley-specified helical edge currents and snake orbits are obtained. Analysis of dynamics indicates that phonon Landau states have extended lifetimes, which are crucial for the realization of Landau-level lasing. Our findings demonstrate the occurrence of the phonon pseudomagnetic field effect in natural materials, which has important implications for the mechanical tuning of phonon quantum states at the atomic scale.

9.
Nano Lett ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739551

RESUMO

The Dzyaloshinskii-Moriya interaction (DMI) is understood to be forbidden by the symmetry of centrosymmetric systems, thus restricting the candidate types for investigating many correlated physical phenomena. Here, we report the hidden DMI existing in centrosymmetric magnets driven by the local inversion symmetry breaking of specific spin sublattices. The opposite DMI spatially localized on the inverse spin sublattice favors the separated spin spiral with opposite chirality. Furthermore, we elucidate that hidden DMI widely exists in many potential candidates, from the first-principles calculations on the mature crystal database. Interestingly, novel topological spin configurations, such as the anti-chirality-locked merons and antiferromagnetic-ferromagnetic meron chains, are stabilized as a consequence of hidden DMI. Our understanding enables the effective control of DMI by symmetry operations at the atomic level and enlarges the range of currently useful magnets for topological magnetism.

10.
Nano Lett ; 24(1): 411-416, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38146896

RESUMO

We elucidate the flexoelectricity of semiconductors in the high strain gradient regime, the underlying mechanism of which is less understood. By using the generalized Bloch theorem, we uncover a strong flexoelectric-like effect in bent thinfilms of Si and Ge due to a high-strain-gradient-induced band gap closure. We show that an unusual type-II band alignment is formed between the compressed and elongated sides of the bent film. Therefore, upon the band gap closure, electrons transfer from the compressed side to the elongated side to reach the thermodynamic equilibrium, leading to a pronounced change of polarization along the film thickness dimension. The obtained transverse flexoelectric coefficients are unexpectedly high with a quadratic dependence on the film thickness. This new mechanism is extendable to other semiconductor materials with moderate energy gaps. Our findings have important implications for the future applications of flexoelectricity in semiconductor materials.

11.
Nano Lett ; 24(7): 2181-2187, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38340079

RESUMO

Recently discovered as an intrinsic antiferromagnetic topological insulator, MnBi2Te4 has attracted tremendous research interest, as it provides an ideal platform to explore the interplay between topological and magnetic orders. MnBi2Te4 displays distinct exotic topological phases that are inextricably linked to the different magnetic structures of the material. In this study, we conducted electrical transport measurements and systematically investigated the anomalous Hall response of epitaxial MnBi2Te4 films when subjected to an external magnetic field sweep, revealing the different magnetic structures stemming from the interplay of applied fields and the material's intrinsic antiferromagnetic (AFM) ordering. Our results demonstrate that the nonsquare anomalous Hall loop is a consequence of the distinct reversal processes within individual septuple layers. These findings shed light on the intricate magnetic structures in MnBi2Te4 and related materials, offering insights into understanding their transport properties and facilitating the implementation of AFM topological electronics.

12.
J Neurosci ; 43(39): 6628-6652, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37620156

RESUMO

A prominent theoretical framework spanning philosophy, psychology, and neuroscience holds that selective attention penetrates early stages of perceptual processing to alter the subjective visual experience of behaviorally relevant stimuli. For example, searching for a red apple at the grocery store might make the relevant color appear brighter and more saturated compared with seeing the exact same red apple while searching for a yellow banana. In contrast, recent proposals argue that data supporting attention-related changes in appearance reflect decision- and motor-level response biases without concurrent changes in perceptual experience. Here, we tested these accounts by evaluating attentional modulations of EEG responses recorded from male and female human subjects while they compared the perceived contrast of attended and unattended visual stimuli rendered at different levels of physical contrast. We found that attention enhanced the amplitude of the P1 component, an early evoked potential measured over visual cortex. A linking model based on signal detection theory suggests that response gain modulations of the P1 component track attention-induced changes in perceived contrast as measured with behavior. In contrast, attentional cues induced changes in the baseline amplitude of posterior alpha band oscillations (∼9-12 Hz), an effect that best accounts for cue-induced response biases, particularly when no stimuli are presented or when competing stimuli are similar and decisional uncertainty is high. The observation of dissociable neural markers that are linked to changes in subjective appearance and response bias supports a more unified theoretical account and demonstrates an approach to isolate subjective aspects of selective information processing.SIGNIFICANCE STATEMENT Does attention alter visual appearance, or does it simply induce response bias? In the present study, we examined these competing accounts using EEG and linking models based on signal detection theory. We found that response gain modulations of the visually evoked P1 component best accounted for attention-induced changes in visual appearance. In contrast, cue-induced baseline shifts in alpha band activity better explained response biases. Together, these results suggest that attention concurrently impacts visual appearance and response bias, and that these processes can be experimentally isolated.


Assuntos
Potenciais Evocados , Córtex Visual , Humanos , Masculino , Feminino , Incerteza , Cognição , Sinais (Psicologia) , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Estimulação Luminosa/métodos , Eletroencefalografia
13.
Neuroimage ; 291: 120596, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38554783

RESUMO

BACKGROUND: Left prefrontal intermittent theta-burst stimulation (iTBS) has emerged as a safe and effective transcranial magnetic stimulation (TMS) treatment protocol in depression. Though network effects after iTBS have been widely studied, the deeper mechanistic understanding of target engagement is still at its beginning. Here, we investigate the feasibility of a novel integrated TMS-fMRI setup and accelerated echo planar imaging protocol to directly observe the immediate effects of full iTBS treatment sessions. OBJECTIVE/HYPOTHESIS: In our effort to explore interleaved iTBS-fMRI feasibility, we hypothesize that TMS will induce acute BOLD signal changes in both the stimulated area and interconnected neural regions. METHODS: Concurrent TMS-fMRI with full sessions of neuronavigated iTBS (i.e. 600 pulses) of the left dorsolateral prefrontal cortex (DLPFC) was investigated in 18 healthy participants. In addition, we conducted four TMS-fMRI sessions in a single patient on long-term maintenance iTBS for bipolar depression to test the transfer to clinical cases. RESULTS: Concurrent TMS-fMRI was feasible for iTBS sequences with 600 pulses. During interleaved iTBS-fMRI, an increase of the BOLD signal was observed in a network including bilateral DLPFC regions. In the clinical case, a reduced BOLD response was found in the left DLPFC and the subgenual anterior cingulate cortex, with high variability across individual sessions. CONCLUSIONS: Full iTBS sessions as applied for the treatment of depressive disorders can be established in the interleaved iTBS-fMRI paradigm. In the future, this experimental approach could be valuable in clinical samples, for demonstrating target engagement by iTBS protocols and investigating their mechanisms of therapeutic action.


Assuntos
Imageamento por Ressonância Magnética , Estimulação Magnética Transcraniana , Humanos , Estimulação Magnética Transcraniana/métodos , Imageamento por Ressonância Magnética/métodos , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Giro do Cíngulo , Córtex Pré-Frontal Dorsolateral
14.
J Am Chem Soc ; 146(5): 3125-3135, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38288596

RESUMO

The chapter on the thiol-related hydrogen bond (H-bond) and its excited-state intramolecular proton-transfer (ESIPT) reaction was recently opened where compound 4'-diethylamino-3-mercaptoflavone (3NTF) undergoes ESIPT in both cyclohexane solution and solid, giving a 710 nm tautomer emission with an anomalously large Stokes shift of 12,230 cm-1. Considering the thiol H-bond to be unconventional compared to the conventional Pauling-type -OH or -NH H-bond, it is thus essential and timely to probe its fundamental difference between their ESIPT. However, thiol-associated ESIPT tends to be nonemissive due to the dominant nπ* character of the tautomeric lowest excited state. Herein, based on the 3-mercaptoflavone scaffold and π-elongation concept, a new series of 4'-substituted-7-diethylamino-3-mercaptoflavones, NTFs, was designed and synthesized with varied H-bond strength and 690-720 nm tautomeric emission upon ultraviolet (UV) excitation in cyclohexane. The order of their H-bonding strength was experimentally determined to be N-NTF < O-NTF < H-NTF < F-NTF, while the rate of -SH ESIPT measured by fluorescence upconversion was F-NTF (398 fs)-1 < H-NTF (232 fs)-1 < O-NTF (123 fs)-1 < N-NTF (101 fs)-1 in toluene. Unexpectedly, the strongest H-bonded F-NTF gives the slowest ESIPT, which does not conform to the traditional ESIPT model. The results are rationalized by the trend of carbonyl oxygen basicity rather than -SH acidity. Namely, the thiol acidity relevant to the H-bond strength plays a minor role in the driving force of ESIPT. Instead, the proton-accepting strength governs ESIPT. That is to say, the noncanonical thiol H-bonding system undergoes an unconventional type of ESIPT.

15.
Hippocampus ; 34(1): 7-13, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37933097

RESUMO

There are limited therapeutic options for patients with Dravet syndrome (DS). The equilibrative nucleoside transporters 1 (ENT1) mediate both the influx and efflux of adenosine across the cell membrane exerted beneficial effects in the treatment of epilepsy. This study aimed to evaluate the anticonvulsant effect of the ENT1 inhibitor in an animal model of DS (Scn1aE1099X/+ mice). J7 (5 mg/kg) treatment was efficacious in elevating seizure threshold in Scn1aE1099X/+ mice after hyperthermia exposure. Moreover, the J7 treatment significantly reduced the frequency of spontaneous excitatory post-synaptic currents (sEPSCs, ~35% reduction) without affecting the amplitude in dentate gyrus (DG) granule cells. Pretreatment with the adenosine A1 receptor (A1R) antagonist, DPCPX, abolished the J7 effects on sEPSCs. These observations suggest that the J7 shows an anticonvulsant effect in hyperthermia-induced seizures in Scn1aE1099X/+ mice. This effect possibly acts on presynaptic A1R-mediated signaling modulation in granule cells.


Assuntos
Epilepsias Mioclônicas , Epilepsia , Humanos , Camundongos , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Nucleosídeos/uso terapêutico , Epilepsias Mioclônicas/tratamento farmacológico , Epilepsias Mioclônicas/genética , Epilepsias Mioclônicas/metabolismo , Neurônios/metabolismo , Modelos Animais de Doenças , Canal de Sódio Disparado por Voltagem NAV1.1/genética
16.
Artigo em Inglês | MEDLINE | ID: mdl-39209206

RESUMO

BACKGROUND & AIMS: A functional cure is an essential endpoint in the management of patients with chronic hepatitis B virus (HBV) infection. We evaluated the cumulative probability and predictors of functional cure in patients with chronic HBV infection after hepatitis B e antigen (HBeAg) seroconversion. METHODS: We retrospectively analyzed 413 (249 males and 164 females) initially HBeAg-positive chronic HBV-infected patients who were followed up for a mean of 26.36 ± 0.53 years. All underwent HBeAg seroconversion during follow-up. A functional cure was defined as durable HBsAg and HBV DNA loss without antiviral treatment for more than 24 weeks. RESULTS: After 10,888 person-years of follow-up, the cumulative probability of functional cure was 14.53% (n = 60). There were 24 (40%) subjects with functional cure after antiviral therapy. The annual functional cure rate was 0.55% per person-year, and increased to 0.96% per person-year after HBeAg seroconversion. In subjects with functional cure, the HBsAg and HBV DNA titers after HBeAg seroconversion were positively correlated with the time to functional cure (P < .001 and < .001, respectively). Multivariate Cox proportional hazards analysis of the cohort revealed that HBeAg seroconversion at <18 years of age, high-genetic-barrier nucleos(t)ide analogue(s) therapy before HBeAg seroconversion, and a serum HBsAg titer <1000 IU/mL at 18 months after HBeAg seroconversion were significant predictors of functional cure (P < .001, .001, and .001, respectively). CONCLUSIONS: In a cohort of chronic HBV-infected patients with long-term follow-up, HBeAg seroconversion in childhood, high-genetic-barrier nucleos(t)ide analogue(s) therapy, and low HBsAg titers after HBeAg seroconversion were significant predictors of functional cure.

17.
Small ; 20(24): e2310732, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38299771

RESUMO

Spherical nucleic acids (SNAs) with exceptional colloidal stability, multiple modularity, and programmability are excellent candidates to address common molecular delivery-related issues. Based on this, the higher targeting accuracy and enhanced controllability of stimuli-responsive SNAs render them precise nanoplatforms with inestimable prospects for diverse biomedical applications. Therefore, tailored diagnosis and treatment with stimuli-responsive SNAs may be a robust strategy to break through the bottlenecks associated with traditional nanocarriers. Various stimuli-responsive SNAs are engineered through the incorporation of multifunctional modifications to meet biomedical demands with the development of nucleic acid functionalization. This review provides a comprehensive overview of prominent research in this area and recent advancements in the utilization of stimuli-responsive SNAs in biosensing, bioimaging, and therapeutics. For each aspect, SNA nanoplatforms that exhibit responsive behavior to both internal stimuli (including sequence, enzyme, redox reactions, and pH) and external stimuli (such as light and temperature) are highlighted. This review is expected to offer inspiration and guidance strategies for the rational design and development of stimuli-responsive SNAs in the field of biomedicine.


Assuntos
Técnicas Biossensoriais , Ácidos Nucleicos , Técnicas Biossensoriais/métodos , Ácidos Nucleicos/química , Humanos , Animais
18.
Small ; 20(11): e2307219, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37882353

RESUMO

High power conversion efficiencies (PCEs) in perovskite solar cells (PSCs) have always been awe-inspiring, but perovskite films scalability is an exacting precondition for PSCs commercial deployment, generally unachievable through the antisolvent technique. On the contrary, in the two-step sequential method, the perovskite's uncontrolled crystallization and unnecessary PbI2 residue impede the device's performance. These two issues motivated to empower the PbI2 substrate with orthorhombic RbPbI3 crystal seeds, which act as grown nuclei and develop orientated perovskites lattice stacks, improving the perovskite films morphologically and reducing the PbI2 content in eventual perovskite films. Thence, achieving a PCE of 24.17% with suppressed voltage losses and an impressive life span of 1140 h in the open air.

19.
Chembiochem ; 25(20): e202400249, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-38819725

RESUMO

Herein, we report the finding that a naturally sunflower pollen-derived microspheres (HSECs) with hierarchical structures can selectively absorb polyC and polyA with high efficiency and affinity. HSECs exhibit the capability to selectively absorb polyC and polyA ssDNA under neutral and acidic conditions. It has been observed that the presence of metal cations, specifically Ca2+, enhances the absorption efficiency of HSECs. Mechanically, this absorption phenomenon can be attributed to both electrostatic interactions and cation-π interactions. Such an appealing property enables the functionalization of HSECs for broad potential biomedical applications, such as microRNA detection.


Assuntos
Helianthus , MicroRNAs , Microesferas , Pólen , MicroRNAs/análise , Helianthus/química , Pólen/química , Poli A/química , DNA/química , Poliaminas/química , DNA de Cadeia Simples/química
20.
Cardiovasc Diabetol ; 23(1): 367, 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39420429

RESUMO

BACKGROUND: Non-alcoholic fatty liver diseases (NAFLDs)/non-alcoholic steatohepatitis (NASH) are the most common liver disorders among patients with type 2 diabetes. Newer classes of glucose-lowering agents (GLAs), such as glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter 2 inhibitors (SGLT2is), have been shown to improve liver-related biomarkers. However, their effects on the development of NAFLD/NASH remain inconclusive. METHODS: A nested case-control study was conducted using Taiwan's National Health Insurance Research Database for 2011-2018. Patients aged ≥ 40 years, diagnosed with type 2 diabetes, having stable non-insulin GLA use, and without NAFLD/NASH history were included. Patients with incident NAFLD/NASH were matched up to 10 randomly sampled controls based on individual's age, gender, cohort entry date, type 2 diabetes diagnosis date, and disease risk score. Conditional logistic regression analyses were employed to estimate the association between liver risk and treatment exposure. Dose-response analysis was also performed. RESULTS: There were 621,438 study patients included for analysis. During 1.8 years of median follow-up, the incidence of NAFLD/NASH was 2.7 per 1000 person-years. After matching, 5,730 incident NAFLD cases (mean age: 57.6 years, male: 53.2%) and 45,070 controls (57.7 years, 52.7%) were identified. Using GLP-1RAs or SGLT2is was associated with an insignificantly lower NAFLD/NASH risk (i.e., odds ratios [95% CIs]: 0.84 [0.46-1.52] and 0.85 [0.63-1.14], respectively) and increased cumulative SGLT2i doses were significantly associated with a reduced NAFLD/NASH risk (0.61 [0.38-0.97]). CONCLUSION: GLP-1RA and SGLT2i therapies in type 2 diabetes patients might prevent NAFLD/NASH development, with a significantly lower risk related to greater treatment exposure.


Assuntos
Bases de Dados Factuais , Diabetes Mellitus Tipo 2 , Receptor do Peptídeo Semelhante ao Glucagon 1 , Hepatopatia Gordurosa não Alcoólica , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/sangue , Masculino , Pessoa de Meia-Idade , Feminino , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Fatores de Risco , Taiwan/epidemiologia , Idoso , Medição de Risco , Incidência , Resultado do Tratamento , Fatores de Tempo , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/efeitos adversos , Adulto , Incretinas/uso terapêutico , Incretinas/efeitos adversos , Estudos de Casos e Controles , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon
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