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RAS oncogenes (collectively NRAS, HRAS and especially KRAS) are among the most frequently mutated genes in cancer, with common driver mutations occurring at codons 12, 13 and 611. Small molecule inhibitors of the KRAS(G12C) oncoprotein have demonstrated clinical efficacy in patients with multiple cancer types and have led to regulatory approvals for the treatment of non-small cell lung cancer2,3. Nevertheless, KRASG12C mutations account for only around 15% of KRAS-mutated cancers4,5, and there are no approved KRAS inhibitors for the majority of patients with tumours containing other common KRAS mutations. Here we describe RMC-7977, a reversible, tri-complex RAS inhibitor with broad-spectrum activity for the active state of both mutant and wild-type KRAS, NRAS and HRAS variants (a RAS(ON) multi-selective inhibitor). Preclinically, RMC-7977 demonstrated potent activity against RAS-addicted tumours carrying various RAS genotypes, particularly against cancer models with KRAS codon 12 mutations (KRASG12X). Treatment with RMC-7977 led to tumour regression and was well tolerated in diverse RAS-addicted preclinical cancer models. Additionally, RMC-7977 inhibited the growth of KRASG12C cancer models that are resistant to KRAS(G12C) inhibitors owing to restoration of RAS pathway signalling. Thus, RAS(ON) multi-selective inhibitors can target multiple oncogenic and wild-type RAS isoforms and have the potential to treat a wide range of RAS-addicted cancers with high unmet clinical need. A related RAS(ON) multi-selective inhibitor, RMC-6236, is currently under clinical evaluation in patients with KRAS-mutant solid tumours (ClinicalTrials.gov identifier: NCT05379985).
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Antineoplásicos , Mutación , Neoplasias , Proteína Oncogénica p21(ras) , Proteínas Proto-Oncogénicas p21(ras) , Animales , Humanos , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Guanosina Trifosfato/metabolismo , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/patología , Proteína Oncogénica p21(ras)/antagonistas & inhibidores , Proteína Oncogénica p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The peptide hormone angiotensin II regulates blood pressure mainly through the type 1 angiotensin II receptor AT1 R and its downstream signaling proteins Gq and ß-arrestin. AT1 R blockers, clinically used as antihypertensive drugs, inhibit both signaling pathways, whereas AT1 R ß-arrestin-biased agonists have shown great potential for the treatment of acute heart failure. Here, we present a cryo-electron microscopy (cryo-EM) structure of the human AT1 R in complex with a balanced agonist, Sar1 -AngII, and Gq protein at 2.9 Å resolution. This structure, together with extensive functional assays and computational modeling, reveals the molecular mechanisms for AT1 R signaling modulation and suggests that a major hydrogen bond network (MHN) inside the receptor serves as a key regulator of AT1 R signal transduction from the ligand-binding pocket to both Gq and ß-arrestin pathways. Specifically, we found that the MHN mutations N1113.35 A and N2947.45 A induce biased signaling to Gq and ß-arrestin, respectively. These insights should facilitate AT1 R structure-based drug discovery for the treatment of cardiovascular diseases.
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Angiotensina II , Transducción de Señal , Humanos , Microscopía por Crioelectrón , Transducción de Señal/fisiología , beta-Arrestinas/metabolismo , Angiotensina II/química , Angiotensina II/metabolismo , Angiotensina II/farmacología , Receptores de Angiotensina/metabolismoRESUMEN
The biophysical properties of lipid vesicles are important for their stability and integrity, key parameters that control the performance when these vesicles are used for drug delivery. The vesicle properties are determined by the composition of lipids used to form the vesicle. However, for a given lipid composition, they can also be tailored by tethering polymers to the membrane. Typically, synthetic polymers like polyethyleneglycol are used to increase vesicle stability, but the use of polysaccharides in this context is much less explored. Here, we report a general method for functionalizing lipid vesicles with polysaccharides by binding them to cholesterol. We incorporate the polysaccharides on the outer membrane leaflet of giant unilamellar vesicles (GUVs) and investigate their effect on membrane mechanics using micropipette aspiration. We find that the presence of the glycolipid functionalization produces an unexpected softening of GUVs with fluid-like membranes. By contrast, the functionalization of GUVs with polyethylene glycol does not reduce their stretching modulus. This work provides the potential means to study membrane-bound meshworks of polysaccharides similar to the cellular glycocalyx; moreover, it can be used for tuning the mechanical properties of drug delivery vehicles.
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Polisacáridos , Liposomas Unilamelares , Liposomas Unilamelares/química , Liposomas Unilamelares/metabolismo , Polisacáridos/química , Polisacáridos/metabolismo , Polietilenglicoles/química , Colesterol/química , Colesterol/metabolismo , Lípidos/químicaRESUMEN
Characterizing unknown viruses is essential for understanding viral ecology and preparing against viral outbreaks. Recovering complete genome sequences from environmental samples remains computationally challenging using metagenomics, especially for low-abundance species with uneven coverage. We present an experimental method for reliably recovering complete viral genomes from complex environmental samples. Individual genomes are encapsulated into droplets and amplified using multiple displacement amplification. A unique gene detection assay, which employs an RNA-based probe and an exonuclease, selectively identifies droplets containing the target viral genome. Labeled droplets are sorted using a microfluidic sorter, and genomes are extracted for sequencing. We demonstrate this method's efficacy by spiking two known viral genomes, Simian virus 40 (SV40, 5,243 bp) and Human Adenovirus 5 (HAd5, 35,938 bp), into a sewage sample with a final abundance in the droplets of around 0.1% and 0.015%, respectively. We achieve 100% recovery of the complete sequence of the spiked-in SV40 genome with uniform coverage distribution. For the larger HAd5 genome, we cover approximately 99.4% of its sequence. Notably, genome recovery is achieved with as few as one sorted droplet, which enables the recovery of any desired genomes in complex environmental samples, regardless of their abundance. This method enables single-genome whole-genome amplification and targeting characterizations of rare viral species and will facilitate our ability to access the mutational profile in single-virus genomes and contribute to an improved understanding of viral ecology.
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Genoma Viral , Virus 40 de los Simios , Genoma Viral/genética , Virus 40 de los Simios/genética , Virus 40 de los Simios/aislamiento & purificación , Metagenómica/métodos , Humanos , Adenovirus Humanos/genética , Adenovirus Humanos/aislamiento & purificación , Aguas del Alcantarillado/virologíaRESUMEN
The quantification and characterization of aggregated α-synuclein in clinical samples offer immense potential toward diagnosing, treating, and better understanding neurodegenerative synucleinopathies. Here, we developed digital seed amplification assays to detect single α-synuclein aggregates by partitioning the reaction into microcompartments. Using pre-formed α-synuclein fibrils as reaction seeds, we measured aggregate concentrations as low as 4 pg/mL. To improve our sensitivity, we captured aggregates on antibody-coated magnetic beads before running the amplification reaction. By first characterizing the pre-formed fibrils with transmission electron microscopy and size exclusion chromatography, we determined the specific aggregates targeted by each assay platform. Using brain tissue and cerebrospinal fluid samples collected from patients with Parkinson's Disease and multiple system atrophy, we demonstrated that the assay can detect endogenous pathological α-synuclein aggregates. Furthermore, as another application for these assays, we studied the inhibition of α-synuclein aggregation in the presence of small-molecule inhibitors and used a custom image analysis pipeline to quantify changes in aggregate growth and filament morphology.
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Atrofia de Múltiples Sistemas , Enfermedad de Parkinson , Sinucleinopatías , Humanos , alfa-Sinucleína , AnticuerposRESUMEN
Gastrin releasing peptide receptor (GRPR), a member of the bombesin (BBN) G protein-coupled receptors, is aberrantly overexpressed in several malignant tumors, including those of the breast, prostate, pancreas, lung, and central nervous system. Additionally, it also mediates non-histaminergic itch and pathological itch conditions in mice. Thus, GRPR could be an attractive target for cancer and itch therapy. Here, we report the inactive state crystal structure of human GRPR in complex with the non-peptide antagonist PD176252, as well as two active state cryo-electron microscopy (cryo-EM) structures of GRPR bound to the endogenous peptide agonist gastrin-releasing peptide and the synthetic BBN analog [D-Phe6, ß-Ala11, Phe13, Nle14] Bn (6-14), in complex with Gq heterotrimers. These structures revealed the molecular mechanisms for the ligand binding, receptor activation, and Gq proteins signaling of GRPR, which are expected to accelerate the structure-based design of GRPR antagonists and agonists for the treatments of cancer and pruritus.
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Neoplasias , Receptores de Bombesina , Masculino , Humanos , Ratones , Animales , Receptores de Bombesina/agonistas , Receptores de Bombesina/metabolismo , Microscopía por Crioelectrón , Bombesina/farmacología , Péptido Liberador de Gastrina/metabolismo , Prurito/metabolismoRESUMEN
A wide range of macromolecules can undergo phase separation, forming biomolecular condensates in living cells. These membraneless organelles are typically highly dynamic, formed reversibly, and carry out essential functions in biological systems. Crucially, however, a further liquid-to-solid transition of the condensates can lead to irreversible pathological aggregation and cellular dysfunction associated with the onset and development of neurodegenerative diseases. Despite the importance of this liquid-to-solid transition of proteins, the mechanism by which it is initiated in normally functional condensates is unknown. Here we show, by measuring the changes in structure, dynamics, and mechanics in time and space, that single-component FUS condensates do not uniformly convert to a solid gel, but rather that liquid and gel phases coexist simultaneously within the same condensate, resulting in highly inhomogeneous structures. Furthermore, our results show that this transition originates at the interface between the condensate and the dilute continuous phase, and once initiated, the gelation process propagates toward the center of the condensate. To probe such spatially inhomogeneous rheology during condensate aging, we use a combination of established micropipette aspiration experiments together with two optical techniques, spatial dynamic mapping and reflective confocal dynamic speckle microscopy. These results reveal the importance of the spatiotemporal dimension of the liquid-to-solid transition and highlight the interface of biomolecular condensates as a critical element in driving pathological protein aggregation.
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Condensados Biomoleculares , Agregación Patológica de Proteínas , Humanos , Microscopía Confocal , Reología , Proteína FUS de Unión a ARNRESUMEN
The testes are the organs of gamete production and testosterone synthesis. Up to date, no model system is available for mammalian testicular development, and only few studies have characterized the mouse testis transcriptome from no more than three postnatal ages. To describe the transcriptome landscape of the developing mouse testis and identify the potential molecular mechanisms underlying testis maturation, we examined multiple RNA-seq data of mouse testes from 3-week-old (puberty) to 11-week-old (adult). Sperm cells appeared as expected in 5-week-old mouse testis, suggesting the proper sample collection. The principal components analysis revealed the genes from 3w to 4w clustered away from other timepoints, indicating they may be the important nodes for testicular development. The pairwise comparisons at two adjacent timepoints identified 7,612 differentially expressed genes (DEGs), resulting in 58 unique mRNA expression patterns. Enrichment analysis identified functions in tissue morphogenesis (3-4w), regulation of peptidase activity (4-5w), spermatogenesis (7-8w), and antigen processing (10-11w), suggesting distinct functions in different developmental periods. 50 hub genes and 10 gene cluster modules were identified in the testis maturation process by protein-protein interaction (PPI) network analysis, and the miRNA-lncRNA-mRNA, miRNA-circRNA-mRNA and miRNA-circRNA-lncRNA-mRNA competing endogenous RNA (ceRNA) networks were constructed. The results suggest that testis maturation is a complex developmental process modulated by various molecules, and that some potential RNA-RNA interactions may be involved in specific developmental stages. In summary, this study provides an update on the molecular basis of testis development, which may help to understand the molecular mechanisms of mouse testis development and provide guidance for mouse reproduction.
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Perfilación de la Expresión Génica , Testículo , Animales , Masculino , Testículo/metabolismo , Testículo/crecimiento & desarrollo , Ratones , Regulación del Desarrollo de la Expresión Génica , Transcriptoma , Redes Reguladoras de Genes , Mapas de Interacción de Proteínas , MicroARNs/genética , MicroARNs/metabolismoRESUMEN
Colorectal cancer (CRC) is a frequent gastrointestinal malignancy with high rates of morbidity and mortality; 85% of these tumours are proficient mismatch repair (pMMR)-microsatellite instability-low (MSI-L)/microsatellite stable (MSS) CRC known as 'cold' tumours that are resistant to immunosuppressive drugs. Monotherapy with programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors is ineffective for treating MSS CRC, making immunotherapy for MSS CRC a bottleneck. Recent studies have found that the multi-pathway regimens combined with PD-1/PD-L1 inhibitors can enhance the efficacy of anti-PD-1/PD-L1 in MSS CRC by increasing the number of CD8+ T cells, upregulating PD-L1 expression and improving the tumour microenvironment. This paper reviews the research progress of PD-1/PD-L1 inhibitors in combination with cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) inhibitors, oncolytic virus, intestinal flora, antiangiogenic agents, chemotherapy, radiotherapy and epigenetic drugs for the treatment of pMMR-MSI-L/MSS CRC.
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Antígeno B7-H1 , Neoplasias Colorrectales , Inhibidores de Puntos de Control Inmunológico , Inmunoterapia , Inestabilidad de Microsatélites , Receptor de Muerte Celular Programada 1 , Humanos , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/terapia , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/farmacología , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Inmunoterapia/métodos , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/metabolismo , Microambiente Tumoral/inmunología , Animales , Terapia CombinadaRESUMEN
Recently, metal-mediated electrochemical conversion of nitrogen and hydrogen to ammonia (M-eNRRs) has been attracting intense research attention as a potential route for ammonia synthesis under ambient conditions. However, which metals should be used to mediate M-eNRRs remains unanswered. This work provides an extensive comparison of the energy consumption in the classical Haber Bosch (H-B) process and the M-eNRRs. The results indicate that when employing lithium and calcium, metals popularly used to mediate the M-eNRRs, the energy consumption is more than 10 times greater than that of the H-B process even assuming a 100% Faradaic efficiency and zero overpotentials. Only electrosynthesis with a cell voltage not exceeding 0.38 V might have the potential to rival the H-B process from an energetic perspective. A further analysis of other metals in the periodic table reveals that only some heavy metals, including In, Tl, Co, Ni, Ga, Mo, Sn, Pb, Fe, W, Ge, Re, Bi, Cu, Po, Tc, Ru, Rh, Ag, Hg, Pd, Ir, Pt, and Au, can potentially consume less energy than that of the H-B process purely from a thermodynamic standpoint, but whether they can activate N2 under ambient conditions is yet to be explored. This work shows the importance of performing thermodynamic analysis for the development of an innovative strategy to synthesize ammonia with the ultimate goal of replacing the H-B process on a large scale.
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Immune checkpoint inhibitors (ICIs) have been extensively used in immunological therapy primarily due to their ability to prolong patient survival. Although ICIs have achieved success in cancer treatment, the resistance of ICIs should not be overlooked. Ferroptosis is a newly found cell death mode characterized by the accumulation of reactive oxygen species (ROS), glutathione (GSH) depletion, and glutathione peroxidase 4 (GPX4) inactivation, which has been demonstrated to be beneficial to immunotherapy and combining ferroptosis and ICIs to exploit new immunotherapies may reverse ICIs resistance. Exosomes act as mediators in cell-to-cell communication that may regulate ferroptosis to influence immunotherapy through the secretion of biological molecules. Thus, utilizing exosomes to target ferroptosis has opened up exciting possibilities for reversing ICIs resistance. In this review, we summarize the mechanisms of ferroptosis improving ICIs therapy and how exosomes regulate ferroptosis through adjusting iron metabolism, blocking the ROS accumulation, controlling ferroptosis defense systems, and influencing classic signaling pathways and how engineered exosomes target ferroptosis and improve ICIs efficiency.
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Resistencia a Antineoplásicos , Exosomas , Ferroptosis , Inhibidores de Puntos de Control Inmunológico , Neoplasias , Animales , Humanos , Exosomas/metabolismo , Ferroptosis/efectos de los fármacos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/farmacología , Inmunoterapia/métodos , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Neoplasias/metabolismo , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Microglial abnormality and heterogeneity are observed in autism spectrum disorder (ASD) patients and animal models of ASD. Microglial depletion by colony stimulating factor 1-receptor (CSF1R) inhibition has been proved to improve autism-like behaviors in maternal immune activation mouse offspring. However, it is unclear whether CSF1R inhibition has extensive effectiveness and pharmacological heterogeneity in treating autism models caused by genetic and environmental risk factors. Here, we report pharmacological functions and cellular mechanisms of PLX5622, a small-molecule CSF1R inhibitor, in treating Cntnap2 knockout and valproic acid (VPA)-exposed autism model mice. For the Cntnap2 knockout mice, PLX5622 can improve their social ability and reciprocal social behavior, slow down their hyperactivity in open field and repetitive grooming behavior, and enhance their nesting ability. For the VPA model mice, PLX5622 can enhance their social ability and social novelty, and alleviate their anxiety behavior, repetitive and stereotyped autism-like behaviors such as grooming and marble burying. At the cellular level, PLX5622 restores the morphology and/or number of microglia in the somatosensory cortex, striatum, and hippocampal CA1 regions of the two models. Specially, PLX5622 corrects neurophysiological abnormalities in the striatum of the Cntnap2 knockout mice, and in the somatosensory cortex, striatum, and hippocampal CA1 regions of the VPA model mice. Incidentally, microglial dynamic changes in the VPA model mice are also reported. Our study demonstrates that microglial depletion and repopulation by transient CSF1R inhibition is effective, and however, has differential pharmacological functions and cellular mechanisms in rescuing behavioral deficits in the two autism models.
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Trastorno Autístico , Modelos Animales de Enfermedad , Proteínas de la Membrana , Ratones Noqueados , Proteínas del Tejido Nervioso , Conducta Social , Ácido Valproico , Animales , Ácido Valproico/farmacología , Ácido Valproico/uso terapéutico , Ratones , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Trastorno Autístico/tratamiento farmacológico , Trastorno Autístico/genética , Trastorno Autístico/inducido químicamente , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones Endogámicos C57BL , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/antagonistas & inhibidores , Masculino , Femenino , Microglía/efectos de los fármacos , Microglía/metabolismo , Microglía/patología , Conducta Animal/efectos de los fármacosRESUMEN
The exploration of new properties and functionality of covalent organic frameworks (COFs) rely mostly on the covalent modification of the starting building blocks or linkages. Noncovalent forces that guide the assembly and adhesion of layers to develop two-dimensional (2D) COFs and improve their bulk properties and functionalities, however, are rarely explored. Herein, the "conformational lock" (CL) effect in 2D hydrazine-linked COFs with intralayer F-H interaction is discovered and regulated to stabilize interlayer adhesion and develop a facile strategy to increase their stability, promote selectivity and efficiency in reactive singlet oxygen (1O2)-triggered photocatalytic transformation when acting as photocatalysts. The CL strategy endows the fluorinated COFs with an efficient intersystem crossing process for 1O2 generation and strong interlayer π-π stacking interaction. The 4F-COF with the strongest F-H noncovalent interaction exhibits the highest photocatalytic conversion and selectivity (exceeding 98%) in typical 1O2-dependent transformations, even over 7 continuous photocatalytic cycles. This work demonstrates that promoting intralayer noncovalent interaction in 2D-COFs can impart high photocatalytic activity and stability, and would vigorously inspire their developments in heterogeneous catalysis.
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BACKGROUND: In the management of complex diseases, the strategic adoption of combination therapy has gained considerable prominence. Combination therapy not only holds the potential to enhance treatment efficacy but also to alleviate the side effects caused by excessive use of a single drug. Presently, the exploration of combination therapy encounters significant challenges due to the vast spectrum of potential drug combinations, necessitating the development of efficient screening strategies. METHODS: In this study, we propose a prediction scoring method that integrates heterogeneous data using a weighted Bayesian method for drug combination prediction. Heterogeneous data refers to different types of data related to drugs, such as chemical, pharmacological, and target profiles. By constructing a multiplex drug similarity network, we formulate new features for drug pairs and propose a novel Bayesian-based integration scheme with the introduction of weights to integrate information from various sources. This method yields support strength scores for drug combinations to assess their potential effectiveness. RESULTS: Upon comprehensive comparison with other methods, our method shows superior performance across multiple metrics, including the Area Under the Receiver Operating Characteristic Curve, accuracy, precision, and recall. Furthermore, literature validation shows that many top-ranked drug combinations based on the support strength score, such as goserelin and letrozole, have been experimentally or clinically validated for their effectiveness. CONCLUSIONS: Our findings have significant clinical and practical implications. This new method enhances the performance of drug combination predictions, enabling effective pre-screening for trials and, thereby, benefiting clinical treatments. Future research should focus on developing new methods for application in various scenarios and for integrating diverse data sources.
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Teorema de Bayes , Humanos , Combinación de Medicamentos , Curva ROC , Reproducibilidad de los Resultados , Quimioterapia CombinadaRESUMEN
Rotation is a critical component in 3D reconstruction systems, where accurate calibration of rotation axis parameters is essential for 3D stitching. In this study, what we believe to be a novel parameters estimation-based method for calibrating rotation axis parameters using 2D planar targets is proposed. Compared to traditional circle fitting methods, this method takes both orientation and position information into account, resulting in better precision performance. By leveraging the transmission of spatial pose relationships, the parameters estimation-based calibration method also effectively mitigates the impact of noise for more accurate calibration of rotation axis parameters. Error validation and 3D reconstruction experiments proved the superior performance of the proposed method. The experiment results demonstrate the effectiveness and applicability of the approach in enhancing the calibration of rotation axis parameters for 3D reconstruction systems.
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Directed evolution generates novel biomolecules with desired functions by iteratively diversifying the genetic sequence of wildtype biomolecules, relaying the genetic information to the molecule with function, and selecting the variants that progresses towards the properties of interest. While traditional directed evolution consumes significant labor and time for each step, continuous evolution seeks to automate all steps so directed evolution can proceed with minimum human intervention and dramatically shortened time. A major application of continuous evolution is the generation of novel enzymes, which catalyze reactions under conditions that are not favorable to their wildtype counterparts, or on altered substrates. The challenge to continuously evolve enzymes lies in automating sufficient, unbiased gene diversification, providing selection for a wide array of reaction types, and linking the genetic information to the phenotypic function. Over years of development, continuous evolution has accumulated versatile strategies to address these challenges, enabling its use as a general tool for enzyme engineering. As the capability of continuous evolution continues to expand, its impact will increase across various industries. In this review, we summarize the working mechanisms of recently developed continuous evolution strategies, discuss examples of their applications focusing on enzyme evolution, and point out their limitations and future directions.
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Evolución Molecular Dirigida , Enzimas , Ingeniería de Proteínas , Enzimas/metabolismo , Enzimas/química , Enzimas/genética , Evolución Molecular Dirigida/métodos , Biocatálisis , HumanosRESUMEN
DNA mixture analysis poses a significant challenge in forensic genetics, particularly when dealing with degraded and trace amount DNA samples. Multi-SNPs (MNPs) are genetic markers similar to microhaplotypes but with smaller molecular sizes (< 75 bp), making them theoretically more suitable for analyzing degraded and trace amount samples. In this case report, we investigated a cold case involving a campstool stored for over a decade, aiming to detect and locate the suspect's DNA. We employed both conventional capillary electrophoresis-based short tandem repeat (CE-STR) analysis and next-generation sequencing-based multi-SNP (NGS-MNP) analysis. The typing results and deconvolution of the mixed CE-STR profiles were inconclusive regarding the presence of the suspect's DNA in the mixed samples. However, through NGS-MNP analysis and presence probability calculations, we determined that the suspect's DNA was present in the samples from Sect. 4-1 with a probability of 1-8.41 × 10- 6 (99.999159%). This evidence contradicted the suspect's statement and aided in resolving the case. Our findings demonstrate the significant potential of MNP analysis for examining degraded and trace amount DNA mixtures in forensic investigations.
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Degradación Necrótica del ADN , Dermatoglifia del ADN , Electroforesis Capilar , Secuenciación de Nucleótidos de Alto Rendimiento , Repeticiones de Microsatélite , Polimorfismo de Nucleótido Simple , Humanos , Dermatoglifia del ADN/métodos , ADN/análisis , Masculino , Análisis de Secuencia de ADNRESUMEN
BACKGROUND: The accuracy of decoding fine motor imagery (MI) tasks remains relatively low due to the dense distribution of active areas in the cerebral cortex. METHODS: To enhance the decoding of unilateral fine MI activity in the brain, a weight-optimized EEGNet model is introduced that recognizes six types of MI for the right upper limb, namely elbow flexion/extension, wrist pronation/supination and hand opening/grasping. The model is trained with augmented electroencephalography (EEG) data to learn deep features for MI classification. To address the sensitivity issue of the initial model weights to classification performance, a genetic algorithm (GA) is employed to determine the convolution kernel parameters for each layer of the EEGNet network, followed by optimization of the network weights through backpropagation. RESULTS: The algorithm's performance on the three joint classification is validated through experiment, achieving an average accuracy of 87.97%. The binary classification recognition rates for elbow joint, wrist joint, and hand joint are respectively 93.92%, 90.2%, and 94.64%. Thus, the product of the two-step accuracy value is obtained as the overall capability to distinguish the six types of MI, reaching an average accuracy of 81.74%. Compared to commonly used neural networks and traditional algorithms, the proposed method outperforms and significantly reduces the average error of different subjects. CONCLUSIONS: Overall, this algorithm effectively addresses the sensitivity of network parameters to initial weights, enhances algorithm robustness and improves the overall performance of MI task classification. Moreover, the method is applicable to other EEG classification tasks; for example, emotion and object recognition.
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Electroencefalografía , Imaginación , Redes Neurales de la Computación , Extremidad Superior , Humanos , Electroencefalografía/métodos , Extremidad Superior/fisiología , Imaginación/fisiología , Adulto , Aprendizaje Profundo , Actividad Motora/fisiología , Adulto Joven , Masculino , Aprendizaje AutomáticoRESUMEN
Improving resource use is a pressing research issue because of the huge potential organic waste market. Composting is a recycling technique, treatment to achieve the dual effect of resource recovery and zero waste. Waste composition varies: for example, chicken manure is rich in protein, straw contains wood fibres, fruit and vegetables contain sugar, and food waste contains starch. When considering combining waste streams for composting, it is important to ask if this approach can reduce overall composting costs while achieving a more concentrated result. Chicken manure, in particular, presents a unique challenge. This is due to its high protein content. The lack of precursor sugars for glucosamine condensation in chicken manure results in lower humus content in the final compost than other composting methods. To address this, we conducted experiments to investigate whether adding sugary fruits and vegetables to a chicken manure composting system would improve compost quality. To improve experimental results, we used sucrose and maltose instead of fruit and vegetable waste. Sugars added to chicken manure composting resulted in a significant increase in humic substance (HS) content, with improvements of 9.0% and 17.4%, respectively, compared to the control. Sucrose and maltose have a similar effect on the formation of humic substances. These results demonstrate the feasibility of composting fruit and vegetable waste with chicken manure, providing a theoretical basis for future composting experiments.
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Compostaje , Eliminación de Residuos , Animales , Estiércol , Pollos , Azúcares , Maltosa , Secuestro de Carbono , Suelo , Sustancias Húmicas , Verduras , Sacarosa , CarbonoRESUMEN
BACKGROUND: The inconsistency between serum total IgE (tIgE) and allergen-specific IgE (sIgE) results is often encountered in clinical practice, but the distribution and influencing factors of the inconsistent results have not been fully understood. OBJECTIVE: The aim of this study was to analyze the distribution and inconsistency between tIgE and sIgE test results. METHODS: A retrospective study, from the electronic medical records of 2139 patients who underwent both tIgE and sIgE tests, from January to December 2023 was reviewed. The tIgE and sIgE results and their distribution, as well as their inconsistency, were analyzed based on sex, age, and disease subgroups. RESULTS: 36.2% of the patients had a positive sIgE, and 43.7% had an elevated tIgE level. sIgE and tIgE results were discordant in nearly 30% of patients, with no difference between genders, while individuals aged over 60 exhibited a significantly higher inconsistency rate than the other age groups, and the inconsistency rate between tIgE and sIgE results was significantly different among different tIgE levels, sIgE grades, positive allergen count and positive allergen types. In addition, patients with chronic urticaria (CU) had a higher inconsistency rate than those with other allergic diseases, but the difference was not statistically significant. CONCLUSION: The overall inconsistency rate between tIgE and sIgE results was about 30%. The elderly group older than 60 years old is more likely to have inconsistent results, and tIgE level, sIgE level, the number and type of positive allergens also affected the consistency of tIgE and sIgE results.