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1.
Reprod Health ; 21(1): 46, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589866

RESUMO

BACKGROUND: Female genital cosmetic procedures have grown rapidly in most parts of the world. Professional organizations have issued warnings about the complications and long-term consequences of these practices. To be able to adopt the right health policies, it is necessary to know why women decide to perform these procedures. Therefore, the present study will be aim to discover the decision-making process involved in performing female genital cosmetic procedures for Iranian women and construct and validate a results-based logic model for healthy public policy. METHODS: The present study was conducted in three phases. In the initial phase, a qualitative study will be conducted with the Corbin and Strauss ground theory approach. The participants in the study will be healthy women who desire or have undergone female genital cosmetic procedures without medical indications. In this phase, purposive and theoretical sampling will guide recruitment and data collection. The data will be collected via semi-structured interviews, field notes and observations of individual interactions. The data will be analysed using the approach of Corbin and Strauss (2015). MAXQDA 2007 software was used for managing the process of data analysis. In the second phase, the development of a results-based logic model for a healthy public policy is performed based on the findings of the first phase of the study, interviews with key informants and a review of the results of the literature in this field. Finally, validation of the designed program will be performed by the nominal group technique with the presence of a group of experts in the third phase. DISCUSSION: The findings of this study, by identifying women's main concerns related to the studied phenomenon, the existing context, participants' reactions and the consequences of the adopted reactions, can be very important in designing a program that fits Iran's cultural characteristics. In this research, a program using a logical model will be presented that is suitable for policymakers, planners and healthcare service providers to be implemented in the social-cultural context of the study.


Female genital cosmetic procedures refer to a group of cosmetic procedures that change the structure and healthy appearance of the female external genitalia to improve sexual performance or body image. The desire to perform these techniques has become popular in most parts of the world. However, scientific societies have warned about the efficiency, effectiveness and side effects of these techniques. According to these points, the present study aims to discover the decision-making process of performing FGCPs for Iranian women and to construct and validate a program for healthy public policy. This study will be performed in three stages. First, a qualitative study and interviews with healthy women who desire or have undergone female genital cosmetic procedures will be performed. In the following, based on the findings of the first stage, interviews with key informants and a review of literature, a program will be presented to reduce or prevent these procedures, and then this program will be validated. Using the designed program, healthcare practitioners will be able to provide women with more effective advice and guidance to make correct and informed decisions. In addition, this program will enable planners and policymakers to take steps to reduce the demand for these actions and make informed decisions by women by changing and adjusting the conditions and context.


Assuntos
Genitália Feminina , Política de Saúde , Feminino , Humanos , Irã (Geográfico) , Lógica , Literatura de Revisão como Assunto
2.
Sci Rep ; 14(1): 6734, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509145

RESUMO

Boolean networks (BNs) have been extensively used to model gene regulatory networks (GRNs). The dynamics of BNs depend on the network architecture and regulatory logic rules (Boolean functions (BFs)) associated with nodes. Nested canalyzing functions (NCFs) have been shown to be enriched among the BFs in the large-scale studies of reconstructed Boolean models. The central question we address here is whether that enrichment is due to certain sub-types of NCFs. We build on one sub-type of NCFs, the chain functions (or chain-0 functions) proposed by Gat-Viks and Shamir. First, we propose two other sub-types of NCFs, namely, the class of chain-1 functions and generalized chain functions, the union of the chain-0 and chain-1 types. Next, we find that the fraction of NCFs that are chain-0 (also holds for chain-1) functions decreases exponentially with the number of inputs. We provide analytical treatment for this and other observations on BFs. Then, by analyzing three different datasets of reconstructed Boolean models we find that generalized chain functions are significantly enriched within the NCFs. Lastly we illustrate that upon imposing the constraints of generalized chain functions on three different GRNs we are able to obtain biologically viable Boolean models.


Assuntos
Redes Reguladoras de Genes , Modelos Genéticos , Lógica , Modelos Biológicos , Algoritmos
3.
PLoS One ; 19(3): e0296864, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38536833

RESUMO

The modeling of uncertain information is an open problem in ontology research and is a theoretical obstacle to creating a truly semantic web. Currently, ontologies often do not model uncertainty, so stochastic subject matter must either be normalized or rejected entirely. Because uncertainty is omnipresent in the real world, knowledge engineers are often faced with the dilemma of performing prohibitively labor-intensive research or running the risk of rejecting correct information and accepting incorrect information. It would be preferable if ontologies could explicitly model real-world uncertainty and incorporate it into reasoning. We present an ontology framework which is based on a seamless synthesis of description logic and probabilistic semantics. This synthesis is powered by a link between ontology assertions and random variables that allows for automated construction of a probability distribution suitable for inferencing. Furthermore, our approach defines how to represent stochastic, uncertain, or incomplete subject matter. Additionally, this paper describes how to fuse multiple conflicting ontologies into a single knowledge base that can be reasoned with using the methods of both description logic and probabilistic inferencing. This is accomplished by using probabilistic semantics to resolve conflicts between assertions, eliminating the need to delete potentially valid knowledge and perform consistency checks. In our framework, emergent inferences can be made from a fused ontology that were not present in any of the individual ontologies, producing novel insights in a given domain.


Assuntos
Ontologias Biológicas , Semântica , Incerteza , Teorema de Bayes , Bases de Conhecimento , Lógica
4.
Biophys J ; 123(8): 1015-1029, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38486450

RESUMO

To survive, adapt, and develop, cells respond to external and internal stimuli by tightly regulating transcription. Transcriptional regulation involves the combinatorial binding of a repertoire of transcription factors to DNA, which often results in switch-like binary outputs akin to Boolean logic gates. Recent experimental studies have demonstrated that in eukaryotes, transcription factor binding to DNA often involves energy expenditure, thereby driving the system out of equilibrium. The governing principles of transcriptional logic operations out of equilibrium remain unexplored. Here, we employ a simple two-input, single-locus model of transcription that can accommodate both equilibrium and nonequilibrium mechanisms. Using this model, we find that nonequilibrium regimes can give rise to all the logic operations accessible in equilibrium. Strikingly, energy expenditure alters the regulatory function of the two transcription factors in a mutually exclusive manner. This allows for the emergence of new logic operations that are inaccessible in equilibrium. Overall, our results show that energy expenditure can expand the range of cellular decision-making without the need for more complex promoter architectures.


Assuntos
Lógica , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Regiões Promotoras Genéticas , DNA/genética
5.
PLoS One ; 19(3): e0300534, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38489250

RESUMO

The networks proposed here show how neurons can be connected to form flip-flops, the basic building blocks in sequential logic systems. The novel neural flip-flops (NFFs) are explicit, dynamic, and can generate known phenomena of short-term memory. For each network design, all neurons, connections, and types of synapses are shown explicitly. The neurons' operation depends only on explicitly stated, minimal properties of excitement and inhibition. This operation is dynamic in the sense that the level of neuron activity is the only cellular change, making the NFFs' operation consistent with the speed of most brain functions. Memory tests have shown that certain neurons fire continuously at a high frequency while information is held in short-term memory. These neurons exhibit seven characteristics associated with memory formation, retention, retrieval, termination, and errors. One of the neurons in each of the NFFs produces all of the characteristics. This neuron and a second neighboring neuron together predict eight unknown phenomena. These predictions can be tested by the same methods that led to the discovery of the first seven phenomena. NFFs, together with a decoder from a previous paper, suggest a resolution to the longstanding controversy of whether short-term memory depends on neurons firing persistently or in brief, coordinated bursts. Two novel NFFs are composed of two and four neurons. Their designs follow directly from a standard electronic flip-flop design by moving each negation symbol from one end of the connection to the other. This does not affect the logic of the network, but it changes the logic of each component to a logic function that can be implemented by a single neuron. This transformation is reversible and is apparently new to engineering as well as neuroscience.


Assuntos
Memória de Curto Prazo , Neurônios , Memória de Curto Prazo/fisiologia , Neurônios/fisiologia , Lógica , Sinapses , Prazer
6.
Analyst ; 149(7): 1976-1980, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38465447

RESUMO

Nucleic acid-based logic gates have shown great potential in biotechnology, medicine as well as diagnostics. Herein, we have constructed pH-responsive logic devices by utilizing HIV-1 TAR hairpins in combination with a thiazole peptide that exhibits turn-on fluorescence upon interacting with TAR RNA or DNA. Based on this, INHIBIT-AND and YES-INHIBIT-AND logic gates were constructed in parallel. The pH alteration leads to conformational changes of the hairpin structure, enabling the construction of a multi-reset reusable logic system which could be developed for in vitro sensing of the HIV-1 viral RNA.


Assuntos
DNA , RNA , RNA/genética , DNA/genética , DNA/química , Lógica , Concentração de Íons de Hidrogênio , Computadores Moleculares
7.
Adv Neurobiol ; 36: 203-225, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468034

RESUMO

From the morphological point of view, the nervous system exhibits a fractal, self-similar geometry at various levels of observations, from single cells up to cell networks. From the functional point of view, it is characterized by a hierarchical organization in which self-similar structures (networks) of different miniaturizations are nested within each other. In particular, neuronal networks, interconnected to form neuronal systems, are formed by neurons, which operate thanks to their molecular networks, mainly having proteins as components that via protein-protein interactions can be assembled in multimeric complexes working as micro-devices. On this basis, the term "self-similarity logic" was introduced to describe a nested organization where, at the various levels, almost the same rules (logic) to perform operations are used. Self-similarity and self-similarity logic both appear to be intimately linked to the biophysical evidence for the nervous system being a pattern-forming system that can flexibly switch from one coherent state to another. Thus, they can represent the key concepts to describe its complexity and its concerted, holistic behavior.


Assuntos
Sistema Nervoso , Neurônios , Humanos , Neurônios/fisiologia , Lógica , Comunicação Celular
8.
Chem Commun (Camb) ; 60(27): 3721-3724, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38482771

RESUMO

Here, we report a DNA tetrahedron dimer for dual membrane protein logic recognition and interaction inhibition. The DNA tetrahedron dimer not only detects dual proteins that are both overexpressed on target cells in "AND" logic, but also inhibits protein interaction by steric hindrance to suppress cell proliferation, offering new insights for cancer cell diagnosis and treatment.


Assuntos
DNA , Proteínas de Membrana , Lógica
9.
ACS Appl Mater Interfaces ; 16(13): 15907-15915, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38508218

RESUMO

DNA circuits based on successive toehold-mediated DNA displacement reactions, particularly entropy-driven DNA circuit (EDC) systems, have attracted considerable attention as powerful enzyme-free tools for dynamic DNA nanotechnology. However, background leakage (noise signal) often occurs when the circuit is executed nonspecifically, even in the absence of the appropriate catalyst DNA (input). This study designed and developed a new latent toehold-mediated DNA circuit (LDC) system that relies on a bulge-loop structure as a latent toehold toward leakage reduction. Furthermore, the number (size) of nucleotides (nt) in the bulge-loop is found to play a significant role in the performance (i.e., leakage, signal, and kinetics) of LDC systems. In fact, the signal rate for the LDC systems increased as the number of nt in the bulge-loop increased from 4 to 8, whereas the leakage rate of the LDC systems with bulge-loops of 7 nt or less was low, but the leakage rate of the LDC system with a bulge-loop of 8 nt increased significantly. Note that the LDC system with the optimal bulge-loop (7 nt) was capable of not only reducing the leakage but also accelerating the circuit speed without any signal loss, unlike methods of reducing the leakage by reducing the signal reported previously for the conventional EDC systems. These facts indicate that the 7 nt bulge-loop acts as a "latent" toehold for the DNA circuit system. By using the amplification function of output signals with an accelerated circuit and reduced leakage, our LDC system with a 7 nt bulge-loop could be applied directly and successfully to signal-amplifying DNA logic gates such as OR and AND gates, and thus, sufficient output signals could be obtained even with a small amount of input. These findings reveal that our LDC systems with a bulge-loop structure can replace the conventional EDC system and have enormous potential in the field of DNA nanotechnology.


Assuntos
DNA , Lógica , DNA/química , Entropia , Nanotecnologia , Nucleotídeos
10.
PLoS One ; 19(3): e0300073, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38452025

RESUMO

In recent years, non-volatile memory elements have become highly appealing for memory applications to implement a new class of storage memory that could replace flash memories in sequential logic applications, with features such as compactness, low power, fast processing speed, high endurance, and retention. The memristor is one such non-volatile element that fits the fundamental blocks of sequential logic circuits, the latch and flip-flop; hence, in this article, a non-volatile latch architecture using memristor ratioed logic (MRL) inverter and CMOS components is focused, with an additional memristor as a memory element. A Verilog-A model was used to create the memristor element. The simulation findings validated the compact, low-voltage, and reliable design of the latch design. We evolved in technology enough to create a master-slave flip-flop and arrange it to function as a counter and a shift register. Power, number of elements, cell size, energy, programming time, and robustness are compared to comparable non-volatile topologies. The proposed non-volatile latch proves non-volatility and can store data with a 24% reduction in power consumption and a near 10% reduction in area.


Assuntos
Nanotecnologia , Tecnologia , Lógica
11.
Chembiochem ; 25(8): e202400080, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38385968

RESUMO

Due to nucleic acid's programmability, it is possible to realize DNA structures with computing functions, and thus a new generation of molecular computers is evolving to solve biological and medical problems. Pioneered by Milan Stojanovic, Boolean DNA logic gates created the foundation for the development of DNA computers. Similar to electronic computers, the field is evolving towards integrating DNA logic gates and circuits by positioning them on substrates to increase circuit density and minimize gate distance and undesired crosstalk. In this minireview, we summarize recent developments in the integration of DNA logic gates into circuits localized on DNA substrates. This approach of all-DNA integrated circuits (DNA ICs) offers the advantages of biocompatibility, increased circuit response, increased circuit density, reduced unit concentration, facilitated circuit isolation, and facilitated cell uptake. DNA ICs can face similar challenges as their equivalent circuits operating in bulk solution (bulk circuits), and new physical challenges inherent in spatial localization. We discuss possible avenues to overcome these obstacles.


Assuntos
DNA , Lógica , DNA/química , Computadores Moleculares
12.
Cognition ; 246: 105744, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38364443

RESUMO

Counterfactual reasoning helps people to learn from the past to prepare for the future. In contrast to English with counterfactual markers that directly signal counterfactual reasoning, Mandarin Chinese indicates counterfactual reasoning by counterfactuality enhancers, which enhance rather than directly signal entry into the counterfactual realm. There are more counterfactuality enhancers in subtractive than additive counterfactual premises. Hence, Chinese-speaking children might more readily interpret subtractive than additive counterfactual premises, leading to better performance on subtractive than additive counterfactual reasoning tasks. This difference between logical structures might be larger in Chinese than English, as English has counterfactual markers, which enable direct inference of counterfactuality regardless of logical structures. Consistent with these propositions, in two experiments, the present study found that Chinese preschool children's accuracy was significantly higher for subtractive than additive counterfactual reasoning. Also, the difference between logical structures was much larger compared to a previous study in UK children using a similar counterfactual reasoning task. Hence, the use of counterfactuality enhancers in Chinese might shape a developmental difference between subtractive and additive counterfactual reasoning. Parents and teachers may attend to this developmental pattern when scaffolding children's counterfactual reasoning growth.


Assuntos
Lógica , Resolução de Problemas , Humanos , Pré-Escolar , Povo Asiático , China
13.
ACS Nano ; 18(9): 6946-6962, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38377037

RESUMO

Pyroptosis mediated by gasdermin protein has shown great potential in cancer immunotherapies. However, the low expression of gasdermin proteins and the systemic toxicity of nonspecific pyroptosis limit its clinical application. Here, we designed a synthetic biology strategy to construct a tumor-specific pyroptosis-inducing nanoplatform M-CNP/Mn@pPHS, in which a pyroptosis-inducing plasmid (pPHS) was loaded onto a manganese (Mn)-doped calcium carbonate nanoparticle and wrapped in a tumor-derived cell membrane. M-CNP/Mn@pPHS showed an efficient tumor targeting ability. After its internalization by tumor cells, the degradation of M-CNP/Mn@pPHS in the acidic endosomal environment allowed the efficient endosomal escape of plasmid pPHS. To trigger tumor-specific pyroptosis, pPHS was designed according to the logic "AND gate circuit" strategy, with Hif-1α and Sox4 as two input signals and gasdermin D induced pyroptosis as output signal. Only in cells with high expression of Hif-1α and Sox4 simultaneously will the output signal gasdermin D be expressed. Since Hif-1α and Sox4 are both specifically expressed in tumor cells, M-CNP/Mn@pPHS induces the tumor-specific expression of gasdermin D and thus pyroptosis, triggering an efficient immune response with little systemic toxicity. The Mn2+ released from the nanoplatform further enhanced the antitumor immune response by stimulating the cGAS-STING pathway. Thus, M-CNP/Mn@pPHS efficiently inhibited tumor growth with 79.8% tumor regression in vivo. We demonstrate that this logic "AND gate circuit"-based gasdermin nanoplatform is a promising strategy for inducing tumor-specific pyroptosis with little systemic toxicity.


Assuntos
Neoplasias , Piroptose , Humanos , Gasderminas , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias/terapia , Imunoterapia , Lógica
14.
Anal Chem ; 96(10): 4120-4128, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38412037

RESUMO

Efficient and accurate acquisition of cellular biomolecular information is crucial for exploring cell fate, achieving early diagnosis, and the effective treatment of various diseases. However, current DNA biosensors are mostly limited to single-target detection, with few complex logic circuits for comprehensive analysis of three or more targets. Herein, we designed a sea anemone-like DNA nanomachine based on DNA strand displacement composed of three logic gates (YES-AND-YES) and delivered into the cells using gold nano bipyramid carriers. The AND gate activation depends on the trigger chain released by upstream DNA strand displacement reactions, while the output signal relies on the downstream DNAzyme structure. Under the influence of diverse inputs (including enzymes, miRNA, and metal ions), the interconnected logic gates simultaneously perform logical analysis on multiple targets, generating a unique output signal in the YES/NO format. This sensor can successfully distinguish healthy cells from tumor cells and can be further used for the diagnosis of different tumor cells, providing a promising platform for accurate cell-type identification.


Assuntos
DNA Catalítico , Anêmonas-do-Mar , Animais , Anêmonas-do-Mar/genética , DNA/química , DNA Catalítico/química , Lógica , Ouro , Computadores Moleculares
15.
Analyst ; 149(6): 1947-1957, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38385166

RESUMO

Advancements in DNA computation have unlocked molecular-scale information processing possibilities, utilizing the intrinsic properties of DNA for complex logical operations with transformative applications in biomedicine. DNA computation shows promise in molecular diagnostics, enabling precise and sensitive detection of genetic mutations and disease biomarkers. Moreover, it holds potential for targeted gene regulation, facilitating personalized therapeutic interventions with enhanced efficacy and reduced side effects. Herein, we have developed six DNAzyme-based logic gates able to process YES, AND, and NOT Boolean logic. The novelty of this work lies in their additional functionalization with a common DNA scaffold for increased cooperativity in input recognition. Moreover, we explored hierarchical input binding to multi-input logic gates, which helped gate optimization. Additionally, we developed a new design of an allosteric hairpin switch used to implement NOT logic. All DNA logic gates achieved the desired true-to-false output signal when detecting a panel of miRNAs, known for their important role in malignancy regulation. This is the first example of DNAzyme-based logic gates having all input-recognizing elements integrated in a single DNA nanostructure, which provides new opportunities for building DNA automatons for diagnosis and therapy of human diseases.


Assuntos
DNA Catalítico , MicroRNAs , Nanoestruturas , Humanos , DNA Catalítico/química , MicroRNAs/genética , DNA/genética , DNA/química , Lógica , Computadores Moleculares
16.
Eval Rev ; 48(3): 427-460, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38261473

RESUMO

Systematic reviews and meta-analyses are viewed as potent tools for generalized causal inference. These reviews are routinely used to inform decision makers about expected effects of interventions. However, the logic of generalization from research reviews to diverse policy and practice contexts is not well developed. Building on sampling theory, concerns about epistemic uncertainty, and principles of generalized causal inference, this article presents a pragmatic approach to generalizability assessment for use with systematic reviews and meta-analyses. This approach is applied to two systematic reviews and meta-analyses of effects of "evidence-based" psychosocial interventions for youth and families. Evaluations included in systematic reviews are not necessarily representative of populations and treatments of interest. Generalizability of results is limited by high risks of bias, uncertain estimates, and insufficient descriptive data from impact evaluations. Systematic reviews and meta-analyses can be used to test generalizability claims, explore heterogeneity, and identify potential moderators of effects. These reviews can also produce pooled estimates that are not representative of any larger sets of studies, programs, or people. Further work is needed to improve the conduct and reporting of impact evaluations and systematic reviews, and to develop practical approaches to generalizability assessment and guide applications of interventions in diverse policy and practice contexts.


Assuntos
Generalização Psicológica , Lógica , Adolescente , Humanos , Revisões Sistemáticas como Assunto
17.
Bioessays ; 46(3): e2300178, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38247183

RESUMO

Protein post-translational modifications (PTMs) play a crucial role in all cellular functions by regulating protein activity, interactions and half-life. Despite the enormous diversity of modifications, various PTM systems show parallels in their chemical and catalytic underpinnings. Here, focussing on modifications that involve the addition of new elements to amino-acid sidechains, I describe historical milestones and fundamental concepts that support the current understanding of PTMs. The historical survey covers selected key research programmes, including the study of protein phosphorylation as a regulatory switch, protein ubiquitylation as a degradation signal and histone modifications as a functional code. The contribution of crucial techniques for studying PTMs is also discussed. The central part of the essay explores shared chemical principles and catalytic strategies observed across diverse PTM systems, together with mechanisms of substrate selection, the reversibility of PTMs by erasers and the recognition of PTMs by reader domains. Similarities in the basic chemical mechanism are highlighted and their implications are discussed. The final part is dedicated to the evolutionary trajectories of PTM systems, beginning with their possible emergence in the context of rivalry in the prokaryotic world. Together, the essay provides a unified perspective on the diverse world of major protein modifications.


Assuntos
Processamento de Proteína Pós-Traducional , Proteínas , Código das Histonas , Ubiquitinação , Lógica
18.
Behav Brain Sci ; 47: e2, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38224085

RESUMO

Glowacki argues that the human capacity for peace emerged 100,000 years ago, and that the logic of peace is such that the traits and technologies that enable peace are the same that are used to wage war. In my commentary I raise some concerns about these points as well as about Glowacki's understanding of peace.


Assuntos
Condições Sociais , Guerra , Humanos , Lógica
19.
Biosens Bioelectron ; 249: 116035, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244294

RESUMO

As the well-known test-indicator for early prostate cancer (PCa), sarcosine (SA) is closely related to the differential pathological process, which makes its accurate determination increasingly significant. Herein, we for the first time expanded the peroxidase (POD)-like property of facile-synthesized Zn-TCPP(Fe) MOF to fluorescent substrates and exploited it to ratiometric fluorescent (RF) sensing. By harnessing the effective catalytic oxidation of MOF nanozyme toward two fluorescent substrates (Scopoletin, SC; Amplex Red, AR) with contrary changes, and target-responsive (SA + SOx)/MOF/(SC + AR) tandem catalytic reaction, we constructed the first MOF nanozyme-based RF sensor for the quantitative determination of SA. Superior to previous works, the operation of this RF sensor is under the guidance of AND-(AND^NAND) contrary logic circuit. The dual-channel binary output changes (from 1/0 to 0/1) not only enable the intelligent logical recognition of SA, bringing strengthened reliability and accuracy, but also manifest the proof-of-concept discrimination of PCa individuals and healthy ones. Through recording the fluorescence alterations of SC (F465) and AR (F585), two segments of linear relationships between ratiometric values (F585/F465) and varied contents of SA are realized successfully. The LOD for SA could reach to as low as 39.98 nM, which outperforms all nanozyme-originated SA sensors reported till now. Moreover, this sensor also demonstrates high selectivity and satisfactory performance in human serum samples. Furthermore, the portable sensing of SA is realized under the assistance of smartphone-based RGB analysis, demonstrating the potential of point-of-care diagnostics of PCa in the future.


Assuntos
Técnicas Biossensoriais , Sarcosina , Masculino , Humanos , Smartphone , Reprodutibilidade dos Testes , Corantes Fluorescentes/química , Lógica , Catálise
20.
Nanoscale ; 16(6): 3107-3112, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38250822

RESUMO

Living organisms switch their intrinsic biological states to survive environmental turbulence, in which temperature changes are prevalent in nature. Most artificial temperature-responsive DNA nanosystems work as switch modules that transit between "ON-OFF" states, making it difficult to construct nanosystems with diverse functions. In this study, we present a general strategy to build multimode nanosystems based on a temperature-responsive DNA strand displacement reaction. The temperature-responsive DNA strand displacement was controlled by tuning the sequence of the substrate hairpin strands and the invading strands. The nanosystems were demonstrated as logic gates that performed a set of Boolean logical functions at specific temperatures. In addition, an adaptive logic gate was fabricated that could exhibit different logic functions when placed in different temperatures. Specifically, upon the same input strands, the logic gate worked as an XOR gate at 10 °C, an OR gate at 35 °C, an AND gate at 46 °C, and was reset at 55 °C. The design and fabrication of the multifunctional nanosystems would help construct advanced temperature-responsive systems that may be used for temperature-controlled multi-stage drug delivery and thermally-controlled multi-step assembly of nanostructures.


Assuntos
Computadores Moleculares , Nanoestruturas , Temperatura , DNA/química , Lógica
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