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Nonanal, (E)-2-nonenal, (E,E)-2,4-nonadienal, and (E,Z)-2,6-nonadienal were used to study the effect of number and position of the unsaturated bond in aliphatic aldehydes on meat flavorings. Cysteine-Amadori and thiazolidine derivatives were synthesized, identified by UPLC-TOF/MS and NMR, and quantitatively by UPLC-MS/MS. The polyunsaturated aldehydes exhibited higher inhibition than monounsaturated aldehydes, and monounsaturated aldehydes exhibited higher inhibition than saturated aldehydes, mainly manifested by the inhibition of the cysteine-Amadori formation and acceleration of the thiazolidine derivatives formation. The effect of unsaturated bonds position in aliphatic aldehydes on the initial Maillard reaction stage was similar. The cysteine played an important role in catalyzing the reaction of aliphatic aldehydes. A total of 109 volatile compounds derived by heating prepared thiazolidine derivatives degradation were detected by GC-MS. Formation pathways of volatile compounds were proposed by retro-aldol, oxidation, etc. Particularly, a route to form thiazole by the decarboxylation reaction of thiazolidine derivatives which derivatives from formaldehyde reacting with cysteine was proposed.
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Digital PCR (dPCR) holds immense potential for precisely detecting nucleic acid markers essential for personalized medicine. However, its broader application is hindered by high consumable costs, complex procedures, and restricted multiplexing capabilities. To address these challenges, an all-in-one dPCR system is introduced that eliminates the need for microfabricated chips, offering fully automated operations and enhanced multiplexing capabilities. Using this innovative oscillation-induced droplet generation technique, OsciDrop, this system supports a comprehensive dPCR workflow, including precise liquid handling, pipette-based droplet printing, in situ thermocycling, multicolor fluorescence imaging, and machine learning-driven analysis. The system's reliability is demonstrated by quantifying reference materials and evaluating HER2 copy number variation in breast cancer. Its multiplexing capability is showcased with a quadruplex dPCR assay that detects key EGFR mutations, including 19Del, L858R, and T790M in lung cancer. Moreover, the digital stepwise melting analysis (dSMA) technique is introduced, enabling high-multiplex profiling of seven major EGFR variants spanning 35 subtypes. This innovative dPCR system presents a cost-effective and versatile alternative, overcoming existing limitations and paving the way for transformative advances in precision diagnostics.
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Neoplasias de la Mama , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa/métodos , Patología Molecular/métodos , Receptores ErbB/genética , Variaciones en el Número de Copia de ADN/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/diagnóstico , Receptor ErbB-2/genética , Reacción en Cadena de la Polimerasa Multiplex/métodos , Mutación , FemeninoRESUMEN
INTRODUCTION: To explore the current situation of exposure of Korean adolescents to secondhand smoke (SHS) in households our study aimed to determine the relationship between family member smoking status, exposure to tobacco information through mass media, and household SHS exposure. METHODS: The present study uses pooled data from the Korean adolescent health behavior online survey conducted in 2015, 2018 and 2021, with 157944 participants. The regression models were used to explore the association between the smoking status of households, and exposure to tobacco information through mass media, and household SHS exposure in adolescents, controlling for potential confounding factors. RESULTS: SHS exposure duration of Korean adolescents in households was 0.88 days per week. The households with smokers including the father (ß=1.087; 95% CI: 1.0-1.126), mother (ß=1.461; 95% CI: 1.379- 1.543), siblings (ß=0.545; 95% CI: 0.493-0.597), grandparents (ß=0.224; 95% CI: 0.174-0.272), and other relatives (ß=0.170; 95% CI: 0.126-0.214), showed a positive association with SHS exposure in adolescents within the household. At the same time, information about anti-smoking ads on television (ß= -0.042; 95% CI: -0.069 - -0.015) and public transportation (ß= -0.031; 95% CI: -0.054 - -0.010), showed a negative association with SHS exposure in adolescents. However, broadcasts, online, and newspaper non-smoking ads were not associated with SHS exposure (p>0.05). In addition, regression models revealed that exposure to cigarette advertising in magazines (ß=0.131; 95% CI: 0.097-0.166), networks (ß=0.151; 95% CI: 0.127-0.175), convenience stores (ß=0.061; 95% CI: 0.035-0.087), and supermarkets (ß=0.133; 95% CI: 0.108-0.158) is associated with SHS exposure in adolescents. Finally, our study showed stronger ties between SHS exposure, family smoking, and tobacco ads in girls. The link between maternal smoking, supermarket ads, and adolescent SHS exposure intensified in 2021 compared to 2015. CONCLUSIONS: Family and media were identified as potential factors associated with SHS exposure in adolescents. Therefore, publicity and education regarding household SHS hazards, and smoking bans in media, can be helpful in protecting adolescents from SHS.
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[This corrects the article DOI: 10.18332/tid/175705.].
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This work describes µMET, a novel microfluidic device for precise microbial enumeration tests (MET), essential in pharmaceutical, cosmetic, and food industries for ensuring microbiological safety standards. The µMET chip, comprising two hydrophobic glass plates, features a 15-µm deep µMET chamber enhanced by nanopillars and air supply units, facilitating both immediate and growth-dependent MET. Experimental results, with E. coli as a model bacterium, demonstrate that µMET provides counting linearity that outperforms traditional hemocytometers. The chip's design mitigates challenges like evaporation and ensures high-resolution imaging, making it a cost-effective and reusable alternative to conventional methods. Notably, bright-field µMET eliminates the need for fluorescent staining, streamlining operations with deep-learning algorithms for bacterial counts. Furthermore, we have developed a high-parallel µMET chip featuring 16 counting chambers, enhancing throughput and accommodating immediate and growth-dependent MET approaches. Its innovative design and adaptability render the µMET chip as a valuable tool for microbiology, medicine, and industry applications.
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Escherichia coli , Microfluídica , Microfluídica/métodos , Coloración y Etiquetado , Dispositivos Laboratorio en un Chip , BacteriasRESUMEN
BACKGROUND: Children affected by severe early childhood caries (S-ECC) usually need comprehensive caries treatment due to the extensive of caries. How the oral microbiome changes after caries therapy within the short-term warrant further study. AIM: This study aimed to investigate the short-term impact of comprehensive caries treatment on the supragingival plaque microbiome of S-ECC children. DESIGN: Thirty-three children aged 2-4 years with severe caries (dt > 7) were recruited. Comprehensive caries treatment was performed under general anesthesia in one session and included restoration, pulp treatment, extraction, and fluoride application. Supragingival plaque was sampled pre- and 1-month posttreatment. The genomic DNA of the supragingival plaque was extracted, and bacterial 16S ribosomal RNA gene sequencing was performed. RESULTS: Our data showed that the microbial community evenness significantly decreased posttreatment. Furthermore, comprehensive caries treatment led to more diverse microbial structures among the subjects. The interbacterial interactions reflected by the microbial community's co-occurrence network tended to be less complex posttreatment. Caries treatment increased the relative abundance of Corynebacterium matruchotii, Corynebacterium durum, Actinomyces naeslundii, and Saccharibacteria HMT-347, as well as Aggregatibacter HMT-458 and Haemophilus influenzae. Meanwhile, the relative abundance of Streptococcus mutans, three species from Leptotrichia, Neisseria bacilliformis, and Provotella pallens significantly decreased posttreatment. CONCLUSION: Our results suggested that comprehensive caries treatment may contribute to the reconstruction of a healthier supragingival microbiome.
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Caries Dental , Microbiota , Humanos , Caries Dental/microbiología , Caries Dental/terapia , Preescolar , Masculino , Femenino , Placa Dental/microbiología , ARN Ribosómico 16SRESUMEN
BACKGROUND: The pathology of keloid and especially the roles of bacteria on it were not well understood. METHODS: In this study, multi-omics analyses including microbiome, metaproteomics, metabolomic, single-cell transcriptome and cell-derived xenograft (CDX) mice model were used to explore the roles of bacteria on keloid disease. FINDINGS: We found that the types of bacteria are significantly different between keloid and healthy skin. The 16S rRNA sequencing and metaproteomics showed that more catalase (CAT) negative bacteria, Clostridium and Roseburia existed in keloid compared with the adjacent healthy skin. In addition, protein mass spectrometry shows that CAT is one of the differentially expressed proteins (DEPs). Overexpression of CAT inhibited the proliferation, migration and invasion of keloid fibroblasts, and these characteristics were opposite when CAT was knocked down. Furthermore, the CDX model showed that Clostridium butyricum promote the growth of patient's keloid fibroblasts in BALB/c female nude mice, while CAT positive bacteria Bacillus subtilis inhibited it. Single-cell RNA sequencing verified that oxidative stress was up-regulated and CAT was down-regulated in mesenchymal-like fibroblasts of keloid. INTERPRETATION: In conclusion, our findings suggest that bacteria and CAT contribute to keloid disease. FUNDING: A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.
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Queloide , Humanos , Femenino , Animales , Ratones , Queloide/genética , Queloide/metabolismo , Queloide/patología , Catalasa/genética , Ratones Desnudos , Multiómica , ARN Ribosómico 16S/genética , Proliferación Celular , Células CultivadasRESUMEN
Nonanal, (E)-2-nonenal, (E,E)-2,4-nonadienal, and (E,Z)-2,6-nonadienal were used to reveal the effect of the number and position of unsaturated bond in aliphatic aldehydes on Maillard reaction for the generation of 88 stewed meat-like volatile compounds. The results showed that (E,E)-2,4-nonadienal and (E,Z)-2,6-nonadienal exhibited greater inhibition of the cysteine reaction with glucose than nonanal and (E)-2-nonenal. However, the positions of the unsaturated bonds in aliphatic aldehydes in the Maillard reaction stage were similar. A carbohydrate module labeling approach was used to present the formation pathways of 34 volatile compounds derived from the Maillard reaction with aliphatic aldehyde systems. The number and position of unsaturated bonds in aliphatic aldehydes generate multiple pathways of flavor compound formation. 2-Propylfuran and (E)-2-(2-pentenyl)furan resulted from aliphatic aldehydes. 5-Butyldihydro-2(3H)-furanone and 2-methylthiophene were produced from the Maillard reaction. 2-Furanmethanol, 2-thiophenecarboxaldehyde, and 5-methyl-2-thiophenecarboxaldehyde were derived from the interaction of aliphatic aldehydes and the Maillard reaction. In Particular, the addition of aliphatic aldehydes changed the formation pathway of 2-propylthiophene, thieno[3,2-b]thiophene, and 2,5-thiophenedicarboxaldehyde. Heatmap and PLS-DA analysis could discriminate volatile compound compositions of the five systems and screen the marker compounds differentiating volatile compounds.
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Cisteína , Glucosa , Cisteína/química , Glucosa/química , Aldehídos/químicaRESUMEN
To comprehensively understand the volatile flavor composition of dry-rendered beef fat, solvent-assisted flavor evaporation (SAFE) with four extraction solvents (dichloromethane, pentane, ethyl ether, and methanol) combined with gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactormetry (GC-O) were performed. GC-MS analysis found 96 different volatile compounds in total using the four extraction solvents. According to the GC-MS results and the heat map and principal component analysis (PCA), most of the volatile compounds resulted from dichloromethane and pentane extraction, followed by ethyl ether. Methanol extraction found a few volatile compounds of higher polarity, which was supplementary to the analysis results. Moreover, GC-O analysis found 73 odor-active compounds in total using the four extraction solvents. The GC-O results found that pentane and dichloromethane extraction had a significantly larger number of odor-active compounds than ethyl ether and methanol extraction. This indicated that pentane and dichloromethane were more effective solvents for the extraction of odor-active compounds than the other two solvents. Finally, a total of 15 compounds of odor-active values (OAVs) ≥ 1 were determined to be the key aroma compounds in the dry-rendered beef fat, including 2-methyl-3-furanthiol, 3-methylthiopropanal, (E,E)-2,4-nonadienal, 12-methyltridecanal, and 1-octen-3-one.
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Within the supergroup Rotosphaeromycetes, or "Holomycota"/"Nucletmycea", there are several well-recognised unicellular clades in the earliest diverging fungi (EDF). However, we know little about their occurrence. Here, we investigated EDF in the rhizosphere and bulk soils from cropland, forest, orchard, and wetland ecosystems around the Beijing-Hebei area, China, to illustrate their niche and ecosystem preference. More than 500 new operational taxonomic units (OTUs) of EDF were detected based on the 18S rRNA genes. Microsporida and Aphelida constitute dominant groups, whereas Rozellosporida was quite rare. Although the EDF community was site-specific, the soil chemical characteristics, vegetation, and other eukaryotic microorganisms were the key factors driving the occurrence of EDF. Moreover, the stochastic process consisted the most of the EDF community assembly.
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Apple is an important cash crop in China, and the prediction of its freshness can effectively reduce its storage risk and avoid economic loss. The change in the concentration of odor information such as ethylene, carbon dioxide, and ethanol emitted during apple storage is an important feature to characterize the freshness of apples. In order to accurately predict the freshness level of apples, an electronic nose system based on a gas sensor array and wireless transmission module is designed, and a neural network prediction model using an improved Sparrow Search Algorithm (SSA) based on chaotic sequence (Tent) to optimize Back Propagation (BP) is proposed. The odor information emitted by apples is studied to complete an apple freshness prediction. Furthermore, by fitting the relationship between the prediction coefficient and the input vector, the accuracy benchmark of the prediction model is set, which further improves the prediction accuracy of apple odor information. Compared with the traditional prediction method, the system has the characteristics of simple operation, low cost, reliable results, mobile portability, and it avoids the damage to apples in the process of freshness prediction to realize non-destructive testing.
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The COVID-19 pandemic has significantly changed the teaching model, promoting educational institutions to initiate more explorations in online teaching. This study examines the factors influencing teachers' online teaching performance and satisfaction in universities during the COVID-19. We applied a model of technology acceptance (TAM), expectation confirmation (ECM), and computer self-efficacy (CSE) to develop a questionnaire. The survey was used to collect data from 347 teachers from 6 universities in eastern China to identify factors affecting teachers' performance and satisfaction during the COVID-19. The results indicated that teachers' performance of online teaching is significantly affected by satisfaction, perceived usefulness, and perceived ease of use of online teaching. Meanwhile, confirmation of online teaching expectations and computer self-efficacy significantly impacted teachers' satisfaction with online teaching. This work is an original empirical study guided by multiple theories. It contributes to the online education literature and provides advice regarding how teachers' online teaching satisfaction and performance can be developed in a situation like the one that occurred with COVID-19. This work also broadens the application of TAM and provides an alternative theoretical framework for future research on teachers' online teaching performance.
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As the seed precursor, the ovule produces the female gametophyte (or embryo sac), and the subsequent double fertilization occurs in it. The integuments emerge sequentially from the integument primordia at the early stages of ovule development and finally enwrap the embryo sac gradually during gametogenesis, protecting and nursing the embryo sac. However, the mechanisms regulating integument development are still obscure. In this study, we show that SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASES (SERKs) play essential roles during integument development in Arabidopsis thaliana. The serk1/2/3 triple mutant shows arrested integuments and abnormal embryo sacs, similar defects also found in the triple loss-of-function mutants of ERECTA family (ERf) genes. Ovules of serk1/2/3 er erl1/2 show defects similar to er erl1/2 and serk1/2/3. Results of yeast two-hybrid analyses, bimolecular fluorescence complementation (BiFC) analyses, and co-immunoprecipitation assays demonstrated that SERKs interact with ERf, which depends on EPIDERMAL PATTERNING FACTOR-LIKE (EPFL) family small peptides. The sextuple mutant epfl1/2/3/4/5/6 shows integument defects similar to both of er erl1/2 and serk1/2/3. Our results demonstrate that ERf-SERK-mediated EPFL signaling orchestrates the development of the female gametophyte and the surrounding sporophytic integuments.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Transducción de Señal , Reproducción , Óvulo Vegetal/metabolismo , Regulación de la Expresión Génica de las PlantasRESUMEN
Recent characterization of the obligate episymbiont Saccharibacteria (TM7) belonging to the candidate phyla radiation (CPR) has expanded the extent of microbial diversity. However, the episymbiotic lifestyle of TM7 is still underexploited due to the deficiency of cultivated representatives. Here, we describe gene-targeted TM7 cultivation guided by repurposing epicPCR (emulsion, paired isolation, and concatenation PCR) to capture in situ TM7âhost associations. Using this method, we obtained a novel Saccharibacteria isolate TM7i and its host Leucobacter aridicollis J1 from Cicadae Periostracum, the castoff shell of cicada. Genomic analyses and microscopic characterizations revealed that TM7i could bind to J1 through twitching-like motility mediated by type IV pili (T4P). We further showed that the inhibition of T4P extrusion suppressed the motility and host adherence of TM7i, resulting in its reduced growth. However, the inactivation of T4P had little effect on the growth of TM7i that had already adhered to J1, suggesting the essential role of T4P in host recognition by TM7i. By capturing CPRâhost association and elaborating the T4P-dependent episymbiotic association mechanism, our studies shed light on the distinct yet widespread lifestyle of CPR bacteria.
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Actinomycetales , Fimbrias Bacterianas , Fimbrias Bacterianas/genética , Bacterias , Reacción en Cadena de la Polimerasa , GenómicaRESUMEN
It is demonstrated that the subjective well-being (SWB) of older people greatly relies on their social participation. However, there are few studies on reciprocity beliefs as a mediating mechanism between social participation and SWB. In this study, 297 participants aged 60 and over in Chengdu, Sichuan Province, China, completed a questionnaire of social participation, reciprocity beliefs, and SWB. We used multiple linear regression and mediation analyses to verify the mediating effect of reciprocity beliefs. Results showed that social participation was positively relative to SWB and reciprocity beliefs, and reciprocity beliefs played an intermediary role in social participation and SWB. These findings suggest the importance of social participation for SWB, with reciprocity beliefs (behaviors) playing a positive mediating role, particularly in China. In conclusion, analysis of the mediating effect of reciprocity beliefs provides us with knowledge that could help in achieving a healthy old age. Additionally, this study opens up new perspectives of research.
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Pueblos del Este de Asia , Participación Social , Humanos , Persona de Mediana Edad , Anciano , China , Estado de Salud , Encuestas y CuestionariosRESUMEN
Post-treatment apical periodontitis (PoAP) occurs when root canal treatment has not adequately eliminated bacterial invasion and infection. Yet little is known about the bacterial composition and changes related to the etiology and pathogenesis of PoAP. In this study, clinical samples classified as root apex (HARD) and periapical granulation tissues (SOFT) were separately collected from 10 patients with PoAP. The microbiota of each sample was characterized by 16S rRNA gene sequencing, and the obtained dataset was coanalyzed with 20 NCBI sequence read archive (SRA) datasets of healthy oral (HO) and primary apical periodontitis (PAP). We observed 2522 operational taxonomic units (OTUs) belonging to 29 phyla, and all samples shared 86.5% of the sequence reads. The OTUs affiliated with Bacteroidetes, Firmicutes, Proteobacteria, Fusobacteria, and Actinobacteria, were identified as core microbiota, which accounted for nearly 90% of 16S rRNA sequences in all samples. However, the principal coordinates analysis (PCoA) of the beta diversity demonstrated that the three periapical statuses have distinct microbial compositions. Compared with HO and PoAP, Actinomyces has a significantly increased abundance in PAP. The microbial diversities in PoAP were significantly lower than those in the HO and PAP (p<0.05). The relative abundance of most bacterial taxa was decreasing, except that Clostridia and Synergistia were increased. Furthermore, we explored the potential metabolic differences of the microbial communities by KEGG pathway prediction. We revealed that the microbiota of PoAP might have a more active metabolic capacity, including carbohydrate metabolism, energy metabolism, and enzyme cofactor/carrier biosynthesis (p<0.05). Our study revealed that invasion of opportunistic pathogens such as Clostridia and Synergistia might play a significant role in PoAP, thus guiding the further study of complex microbial-host interactions and the development of more effective diagnostic and therapeutic methods.
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Microbiota , Periodontitis Periapical , Bacterias/genética , Coenzimas , ADN Bacteriano/análisis , ADN Bacteriano/genética , Firmicutes/genética , Humanos , Microbiota/genética , Periodontitis Periapical/microbiología , Periodontitis Periapical/terapia , ARN Ribosómico 16S/genéticaRESUMEN
In the development of new cancer treatment, an essential step is to determine the maximum tolerated dose in a phase I clinical trial. In general, phase I trial designs can be classified as either model-based or algorithm-based approaches. Model-based phase I designs are typically more efficient by using all observed data, while there is a potential risk of model misspecification that may lead to unreliable dose assignment and incorrect maximum tolerated dose identification. In contrast, most of the algorithm-based designs are less efficient in using cumulative information, because they tend to focus on the observed data in the neighborhood of the current dose level for dose movement. To use the data more efficiently yet without any model assumption, we propose a novel approximate Bayesian computation approach to phase I trial design. Not only is the approximate Bayesian computation design free of any dose-toxicity curve assumption, but it can also aggregate all the available information accrued in the trial for dose assignment. Extensive simulation studies demonstrate its robustness and efficiency compared with other phase I trial designs. We apply the approximate Bayesian computation design to the MEK inhibitor selumetinib trial to demonstrate its satisfactory performance. The proposed design can be a useful addition to the family of phase I clinical trial designs due to its simplicity, efficiency and robustness.
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Teorema de Bayes , Ensayos Clínicos Fase I como Asunto , Algoritmos , Simulación por Computador , Dosis Máxima ToleradaRESUMEN
Bacteria have evolved multiple signal transduction systems that permit an adaptation to changing environmental conditions. Chemoreceptor-based signaling cascades are very abundant in bacteria and are among the most complex signaling systems. Currently, our knowledge on the molecular features that determine signal recognition at chemoreceptors is limited. Chemoreceptor McpA of Bacillus velezensis SQR9 has been shown to mediate chemotaxis to a broad range of different ligands. Here we show that its ligand binding domain binds directly 13 chemoattractants. We provide support that organic acids and amino acids bind to the membrane-distal and membrane-proximal module of the dCache domain, respectively, whereas binding of sugars/sugar alcohols occurred at both modules. Structural biology studies combined with site-directed mutagenesis experiments have permitted to identify 10 amino acid residues that play key roles in the recognition of multiple ligands. Residues in membrane-distal and membrane-proximal regions were central for sensing organic acids and amimo acids, respectively, whereas all residues participated in sugars/sugar alcohol sensing. Most characterized chemoreceptors possess a narrow and well-defined ligand spectrum. We propose here a sensing mechanism involving both dCache modules that allows the integration of very diverse signals by a single chemoreceptor.
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Bacillus , Proteínas Bacterianas , Quimiotaxis , Proteínas Quimiotácticas Aceptoras de Metilo , Bacillus/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Ligandos , Proteínas Quimiotácticas Aceptoras de Metilo/química , Proteínas Quimiotácticas Aceptoras de Metilo/metabolismo , Unión Proteica , Dominios Proteicos , Azúcares/químicaRESUMEN
This paper describes OsciDrop, a versatile chip-free droplet generator used to produce size-tunable droplets on demand. Droplet generation is fundamental to miniaturized analysis. We designed OsciDrop to segment the fluid flowing out of the orifice of a disposable pipette tip into droplets by oscillating its distal end underneath an immiscible continuous phase. We described the theoretical model and investigated the effect of flow rate, oscillating amplitude, frequency, and waveform on droplet generation. Our study revealed a previously underexplored Weber number-dominated regime that leverages inertial force instead of viscous force to generate droplets. The same pipette tip allowed robust and deterministic generation of monodisperse droplets with programmable sizes ranging from 200 pL to 2 µL by asymmetrical oscillation. We validated this platform with two droplet-based nucleic acid amplification tests: a digital loop-mediated isothermal amplification assay for absolute quantification of African swine fever virus and a multi-volume digital polymerase chain reaction assay for the high dynamic range measurement of human genomic DNA. The OsciDrop method opens a facile avenue to miniaturization, integration, and automation, exhibiting full accessibility for digital molecular diagnostics.
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Virus de la Fiebre Porcina Africana , Animales , Bioensayo , ADN/genética , Patología Molecular , Reacción en Cadena de la Polimerasa , PorcinosRESUMEN
Enzymes that can decompose synthetic plastics such as polyethylene terephthalate (PET) are urgently needed. Still, a bottleneck remains due to a lack of techniques for detecting and sorting environmental microorganisms with vast diversity and abundance. Here, we developed a fluorescence-activated droplet sorting (FADS) pipeline for high-throughput screening of PET-degrading microorganisms or enzymes (PETases). The pipeline comprises three steps: generation and incubation of droplets encapsulating single cells, picoinjection of fluorescein dibenzoate (FDBz) as the fluorogenic probe, and screening of droplets to obtain PET-degrading cells. We characterized critical factors associated with this method, including specificity and sensitivity for discriminating PETase from other enzymes. We then optimized its performance and compatibility with environmental samples. The system was used to screen a wastewater sample from a PET textile mill. We successfully obtained PET-degrading species from nine different genera. Moreover, two putative PETases from isolates Kineococcus endophyticus Un-5 and Staphylococcus epidermidis Un-C2-8 were genetically derived, heterologously expressed, and preliminarily validated for PET-degrading activities. We speculate that the FADS pipeline can be widely adopted to discover new plastic-degrading microorganisms and enzymes in various environments and may be utilized in the directed evolution of degrading enzymes using synthetic biology.