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BACKGROUND: The efficacy of Vonoprazan-amoxicillin dual therapy (VAT) in the treatment of Helicobacter pylori (H. pylori) is controversial. AIM: To evaluate the efficacy of VAT in the Chinese population. METHODS: This prospective, multicenter, randomized, open-label, and two-stage study was conducted at 23 centers in Fujian, China (May 2021-April 2022). H. pylori-infected patients were randomized to bismuth quadruple therapy (BQT), BQT-Vonoprazan (BQT-V), seven-day VAT (VAT-7), ten-day VAT (VAT-10), and fourteen-day VAT (VAT-14) groups. The primary endpoint was the H. pylori eradication rate. The secondary endpoint was the frequency of adverse events. This study was registered with the Chinese Clinical Trial Registry, ChiCTR2100045778. RESULTS: In the first stage, VAT-7 and BQT-V groups were selected for early termination because less than 23 among 28 cases were eradicated. In the second stage, the eradication rates for BQT, VAT-10, and VA-14 were 80.2% [95% confidence interval (95%CI): 71.4%-86.8%], 93.2% (86.6%-96.7%), 92.2% (85.3%-96.0%) in the intention-to-treat (ITT) analysis, and 80.9% (95%CI: 71.7%-87.5%), 94.0% (87.5%-97.2%), and 93.9% (87.4%-97.2%) in the per-protocol analysis. The ITT analysis showed a higher eradication rate in the VAT-10 and VAT-14 groups than in the BQT group (P = 0.022 and P = 0.046, respectively). The incidence of adverse events in the VAT-10 and VAT-14 groups was lower than in the BQT group (25.27% and 13.73% vs 37.62%, respectively; P < 0.001). CONCLUSION: VAT with a duration of 10 or 14 days achieves a higher eradication rate than the BQT, with a more tolerable safety profile in H. pylori-infected patients in Fujian.
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Amoxicilina , Antibacterianos , Quimioterapia Combinada , Infecções por Helicobacter , Helicobacter pylori , Inibidores da Bomba de Prótons , Pirróis , Sulfonamidas , Humanos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/diagnóstico , Pessoa de Meia-Idade , Masculino , Sulfonamidas/efeitos adversos , Sulfonamidas/administração & dosagem , Sulfonamidas/uso terapêutico , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/isolamento & purificação , Feminino , Estudos Prospectivos , Amoxicilina/administração & dosagem , Amoxicilina/efeitos adversos , Amoxicilina/uso terapêutico , China/epidemiologia , Quimioterapia Combinada/métodos , Pirróis/uso terapêutico , Pirróis/efeitos adversos , Pirróis/administração & dosagem , Resultado do Tratamento , Adulto , Inibidores da Bomba de Prótons/uso terapêutico , Inibidores da Bomba de Prótons/administração & dosagem , Inibidores da Bomba de Prótons/efeitos adversos , Antibacterianos/efeitos adversos , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Idoso , População do Leste AsiáticoRESUMO
Non-Hermitian physics has emerged as a new paradigm that profoundly changes our understanding of non-equilibrium systems, introducing novel concepts such as exceptional points, spectral topology, and non-Hermitian skin effects (NHSEs). Most existing studies focus on non-Hermitian eigenstates, whereas dynamic properties have been discussed only recently, and the dynamic NHSEs are not yet confirmed in experiments. Here, we report the experimental observation of non-Hermitian skin dynamics using tunable one-dimensional nonreciprocal double-chain mechanical systems with glide-time symmetry. Remarkably, dynamic NHSEs are observed with various behaviors in different dynamic phases, which can be understood via the generalized Brillouin zone and the related concepts. Moreover, the observed dynamic NHSEs, amplifications, bulk unidirectional wave propagation, and boundary wave trapping provide promising ways to manipulate waves in a controllable and robust way. Our findings open a new pathway toward non-Hermitian dynamics, which will fertilize the study of non-equilibrium phases of matter.
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Evidence on the link of long-term exposure to ozone (O3) with childhood asthma, rhinitis, conjunctivitis and eczema is inconclusive. We did a population-based cross-sectional survey, including 177,888 children from 173 primary and middle schools in 14 Chinese cities. A satellite-based spatiotemporal model was employed to assess four-year average O3 exposure at both residential and school locations. Information on asthma, allergic rhinitis, eczema and conjunctivitis was collected by a standard questionnaire developed by the American Thoracic Society. We used generalized non-linear and linear mixed models to test the associations. We observed linear exposure-response associations between O3 and all outcomes. The odds ratios of doctor-diagnosed asthma, rhinitis, eczema, and conjunctivitis associated with per interquartile increment in home-school O3 concentration were 1.31 (95 % confidence interval [CI]: 1.28, 1.34), 1.25 (95 %CI: 1.23, 1.28), 1.19 (95 %CI: 1.16, 1.21), and 1.28 (95 %CI: 1.21, 1.34), respectively. Similar associations were observed for asthma-related outcomes including current asthma, wheeze, current wheeze, persistent phlegm, and persistent cough. Moreover, stronger associations were observed among children who were aged > 12 years, physically inactive, and exposed to higher temperature. In conclusion, long-term O3 exposure was associated with higher risks of asthma, allergic rhinitis, conjunctivitis and eczema in children.
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Transition metals exhibit high reactivity for Fenton-like catalysis in environmental remediation, but how to save consumption and reduce pollution is of great interest. In this study, rationally designed defect-engineered Fe@MoS2 (Fe@D-MoS2) was prepared by incorporating reactive iron onto structural defects generated from the chemical acid-etching, aiming to improve the energetic consumption of the catalyst in Fenton-like applications. Morphological and structural properties were elucidated in details, the Fenton-like reactivity was evaluated with five phenolic contaminants for oxidant activation, radical generation and environmental remediation. Compared to Fe@MoS2, Fe@D-MoS2 exhibited a 18.9-fold increase in phenol degradation (0.09 versus 1.79 min-1). Quenching experiments, electron paramagnetic resonance tests and electrochemical measurements revealed the dominant sulfate and superoxide radicals. Rendered by strong metal-substrate surface and electronic interactions from regulated chemical environment and coordination structure, the inert ≡Fe(III) was reduced to the reactive ≡Fe(II) accompanied by the ≡Mo(IV) oxidation to ≡Mo(V) in MoS2 lattice, with adjacent sulfur serving as the key electron transfer bridge. Therefore, this work shows that the incorporation of reactive centers is able to boost two-dimensional sulfide materials for environmental catalysis applications.
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The microbially-mediated reduction processes have potential for the bioremediation of acid mine drainage (AMD), which represents a worldwide environment problem. However, we know little about the microbial interactions in anaerobic AMD sediments. Here we utilized genome-resolved metagenomics to uncover the nature of cooperative and competitive metabolic interactions in 90 AMD sediments across Southern China. Our analyses recovered well-represented prokaryotic communities through the reconstruction of 2625 population genomes. Functional analyses of these genomes revealed extensive metabolic handoffs which occurred more frequently in nitrogen metabolism than in sulfur metabolism, as well as stable functional redundancy across sediments resulting from populations with low genomic relatedness. Genome-scale metabolic modeling showed that metabolic competition promoted microbial co-occurrence relationships, suggesting that community assembly was dominated by habitat filtering in sediments. Notably, communities colonizing more extreme conditions tended to be highly competitive, which was typically accompanied with increased network complexity but decreased stability of the microbiome. Finally, our results demonstrated that heterotrophic Thermoplasmatota associated with ferric iron and sulfate reduction contributed most to the elevated levels of competition. Our study shed light on the cooperative and competitive metabolisms of microbiome in the hazardous AMD sediments, which may provide preliminary clues for the AMD bioremediation in the future.
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We conducted a thorough genome-wide investigation of protein phosphorylation in the halotolerant bacterium Mangrovibacter phragmitis (MPH) ASIOC01, using the Fe-IMAC enrichment method combined with tandem mass spectrometry under low- and high-salinity conditions. The phosphoproteome comprises 86 unique phosphorylated proteins, crucially involving pathways such as glycolysis/gluconeogenesis, the citrate cycle, chaperones, ribosomal proteins, and cell division. This study represents the first and most extensive investigation to-date comparing the bacterial phosphoproteome under different osmotic conditions using a gel-free approach. We identified 45 unique phosphoproteins in MPH cultured in media containing 1 % NaCl, and 33 exclusive phosphoproteins in MPH cultured in media containing 5 % NaCl. Eight phosphoproteins were detected in both growth conditions. Analysis of high-confidence phosphosites reveals that phosphorylation predominantly occurs on serine residues (52.3 %), followed by threonine (35.1 %) and tyrosine (12.6 %) residues. Interestingly, 34 % of the phosphopeptides display multiple phosphosites. Currently, prokaryotic phosphorylation site prediction platforms like MPSite and NetPhosBac 1.0 demonstrate an average prediction accuracy of only 21 % when applied to our dataset. Fourteen phosphoproteins did not yield matches when compared against dbPSP 2.0 (database of Phosphorylation Sites in Prokaryotes), indicating that these proteins may be novel phosphoproteins. These unique proteins undergoing phosphorylation under high salinity growth conditions potentially enhance their adaptive capabilities to environmental challenges.
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This study investigated the effect of anaerobic treatment on the non-volatile components and angiotensin-converting enzyme (ACE) inhibitory activity in purple-colored leaf tea. Results showed that after 8 h of anaerobic treatment, the γ-aminobutyric acid (GABA) content significantly increased from 0.02 mg/g to 1.72 mg/g (p < 0.05), while lactic acid content gradually rose from non-detectable levels to 3.56 mg/g. Notably, certain flavonols like quercetin and myricetin exhibited significant increments, whereas the total anthocyanins (1.01 mg/g) and epigallocatechin-3-(3''-O-methyl) gallate (13.47 mg/g) contents remained almost unchanged. Furthermore, the ACE inhibition rate of purple-colored leaf tea increased significantly from 42.16% to 49.20% (p < 0.05) at a concentration of 2 mg/mL. Moreover, galloylated catechins showed stronger ACE inhibitory activity than non-galloylated catechins in both in vitro ACE inhibitory activity and molecular docking analysis. These findings might contribute to the development of special purple-colored leaf tea products with potential therapy for hypertension.
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Endophytic fungus Serendipita indica can bolster plant growth and confer protection against various biotic and abiotic stresses. However, S. indica-reshaped rhizosphere microecology interactions and root-soil interface processes in situ at the submicrometer scale remain poorly understood. We combined amplicon sequencing and high-resolution nano X-ray fluorescence (nano-XRF) imaging of the root-soil interface to reveal cadmium (Cd) rhizosphere processes. S. indica can successfully colonize the roots of Sedum alfredii Hance, which induces a remarkable increase in shoot biomass by 211.32% and Cd accumulation by 235.72%. Nano-XRF images showed that S. indica colonization altered the Cd distribution in the rhizosphere and facilitated the proximity of more Cd and sulfur (S) to enter the roots and transport to the shoot. Furthermore, the rhizosphere-enriched microbiota demonstrated a more stable network structure after the S. indica inoculation. Keystone species were strongly associated with growth promotion and Cd absorption. For example, Comamonadaceae are closely related to the organic acid cycle and S bioavailability, which could facilitate Cd and S accumulation in plants. Meanwhile, Sphingomonadaceae could release auxin and boost plant biomass. In summary, we construct a mutualism system for beneficial fungi and hyperaccumulation plants, which facilitates high-efficient remediation of Cd-contaminated soils by restructuring the rhizosphere microbiota.
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Cádmio , Microbiota , Rizosfera , Sedum , Poluentes do Solo , Enxofre , Cádmio/metabolismo , Sedum/metabolismo , Poluentes do Solo/metabolismo , Enxofre/metabolismo , Basidiomycota , Solo/química , Biodegradação Ambiental , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologiaRESUMO
Bivalves are often employed for biomonitoring contaminants in marine environments; however, in these large-scale programs, unavoidably, using multiple species presents a significant challenge. Interspecies differences in contaminant bioaccumulation can complicate data interpretation, and direct comparisons among species may result in misleading conclusions. Here, we propose a robust framework based on toxicokinetic measurements that accounts for interspecies differences in bioaccumulation. Specifically, via a recently developed double stable isotope tracer technique, we determined the toxicokinetics of cadmium (Cd)âa metal known for its high concentrations in bivalves and significant interspecies bioaccumulation variabilityâin six widespread bivalve species including mussels (Perna viridis, Mytilus unguiculatus, Mytilus galloprovincialis) and oysters (Magallana gigas, Magallana hongkongensis, Magallana angulata). Results show that oysters generally have higher Cd uptake rate constants (ku: 1.18-3.09 L g-1 d-1) and lower elimination rate constants (ke: 0.008-0.017 d-1) than mussels (ku: 0.21-0.64 L g-1 d-1; ke: 0.018-0.037 d-1). The interspecies differences in tissue Cd concentrations are predominantly due to Cd uptake rather than elimination. Utilizing toxicokinetic parameters to back-calculate Cd concentrations in seawater, we found that the ranking of Cd contamination levels at the six sites markedly differs from those based on tissue Cd concentrations. We propose that this approach will be useful for interpreting data from past and future biomonitoring programs.
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Bivalves , Cádmio , Toxicocinética , Poluentes Químicos da Água , Animais , Cádmio/metabolismo , Cádmio/farmacocinética , Cádmio/toxicidade , Bivalves/metabolismo , Monitoramento Ambiental/métodos , Mytilus/metabolismo , Monitoramento Biológico , Especificidade da EspécieRESUMO
As smart materials, electrorheological elastomers (EREs) formed by pre-treating active electrorheological particles are attracting more and more attention. In this work, four Mg-doped strontium titanate (Mg-STO) particles with spherical, dendritic, flake-like, and pinecone-like morphologies were obtained via hydrothermal and low-temperature co-precipitation. XRD, SEM, Raman, and FT-IR were used to characterize these products. The results showed that Mg-STOs are about 1.5-2.0 µm in size, and their phase structures are dominated by cubic crystals. These Mg-STOs were dispersed in a hydrogel composite elastic medium. Then, Mg-STO/glycerol/gelatin electrorheological composite hydrophilic elastomers were obtained with or without an electric field. The electric field response properties of Mg-doped strontium titanate composite elastomers were investigated. We concluded that dendritic Mg-STO composite elastomers are high-performance EREs, and the maximum value of their energy storage was 8.70 MPa. The significant electrorheological performance of these products is helpful for their applications in vibration control, force transducers, smart structures, dampers, and other fields.
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Lymphocyte decline, particularly the depletion of NK cells, is a prominent feature of immunosuppression following severe tissue injury, heightening the susceptibility of severe trauma patients to life-threatening infections. Previous research indicates that the reduction in the number of NK cells is closely associated with the process of cell death. Nonetheless, the precise mechanism of NK cell death remains unknown. Here, we discovered that following severe traumatic injury, NK cells undergo several cell death pathways, dominated by apoptosis and pyroptosis with coexistence of necrotic cell death, immunogenic cell death, ferroptosis, and autophagy. These NK cells with different paradigms of death have diverse cytokine expression profiles and diverse interactions with other immune cells. Further exploration revealed that hypoxia was strongly associated with this diverse paradigm of NK cell death. Detailed investigation of paradigms of cell death may help to enhance comprehension of lymphopenia post-severe trauma, to develop new strategy in preventing immunosuppression, and then to improve outcome for severe trauma population.
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Células Matadoras Naturais , Ferimentos e Lesões , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Humanos , Ferimentos e Lesões/imunologia , Ferimentos e Lesões/patologia , Masculino , Autofagia , Ferroptose , Piroptose , Apoptose , Animais , Morte Celular , Citocinas/metabolismo , Feminino , Necrose , AdultoRESUMO
Spider silk is a high-performance biomaterial known for its outstanding combination of strength and flexibility. Among the six distinct types of spider silk, eggcase silk stands out as it is exclusively produced from the tubuliform gland, playing a specialized role in offspring protection. In the spider species Latrodectus hesperus, eggcase silk is spun from a large spidroin complex, including the major silk component tubuliform spidroin 1 (TuSp1) and at least six different minor silk components. One of these minor components is eggcase protein 3 (ECP3), a small silk protein of 11.8 kDa that lacks the typical spidroin architecture. ECP3 shows very limited homology to all known spidroins. In this study, we report nearly complete backbone and side-chain resonance assignments of ECP3 as a basis for studying the structural mechanisms involved in eggcase silk formation.
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The widespread application of genome editing to treat or even cure disease requires the delivery of genome editors into the nucleus of target cells. Enveloped Delivery Vehicles (EDVs) are engineered virally-derived particles capable of packaging and delivering CRISPR-Cas9 ribonucleoproteins (RNPs). However, the presence of lentiviral genome encapsulation and replication components in EDVs has obscured the underlying delivery mechanism and precluded particle optimization. Here we show that Cas9 RNP nuclear delivery is independent of the native lentiviral capsid structure. Instead, EDV-mediated genome editing activity corresponds directly to the number of nuclear localization sequences on the Cas9 enzyme. EDV structural analysis using cryo-electron tomography and small molecule inhibitors guided the removal of ~80% of viral residues, creating a minimal EDV (miniEDV) that retains full RNP delivery capability. MiniEDVs are 25% smaller yet package equivalent amounts of Cas9 RNPs relative to the original EDVs, and demonstrated increased editing in cell lines and therapeutically-relevant primary human T cells. These results show that virally-derived particles can be streamlined to create efficacious genome editing delivery vehicles that could simplify production and manufacturing.
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The physiological and genotypic characteristics of Mangrovibacter (MGB) remain largely unexplored, including their distribution and abundance within ecosystems. M. phragmitis (MPH) ASIOC01 was successfully isolated from activated sludge (AS), which was pre-enriched by adding 1,3-dichloro-2-propanol and 3-chloro-1,2-propanediol as carbon sources. The new isolate, MPH ASIOC01, exhibited resilience in a medium containing sodium chloride concentration up to 11% (with optimal growth observed at 3%) and effectively utilizing glycerol as their sole carbon source. However, species delimitation of MGBs remains challenging due to high 16S rRNA sequence similarity (greater than 99% ANI) among different MGBs. In contrast, among the housekeeping gene discrepancies, the tryptophan synthase beta chain gene can serve as a robust marker for fast species delimitation among MGBs. Furthermore, the complete genome of MPH ASIOC01 was fully sequenced and circlized as a single contig using the PacBio HiFi sequencing method. Comparative genomics revealed genes potentially associated with various phenotypic features of MGBs, such as nitrogen-fixing, phosphate-solubilizing, cellulose-digesting, Cr-reducing, and salt tolerance. Computational analysis suggested that MPH ASIOC01 may have undergone horizontal gene transfer events, possibly contributing unique traits such as antibiotic resistance. Finally, our findings also disclosed that the introduction of MPH ASIOC01 into AS can assist in the remediation of wastewater chemical oxygen demand, which was evaluated using gas chromatograph-mass spectrometry. To the best of our knowledge, this study offers the most comprehensive understanding of the phenotypic and genotypic features of MGBs to date.
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This systematic review and meta-analysis aimed to compare perioperative and oncologic outcomes in patients with pancreatic ductal adenocarcinoma (PDAC) treated with robotic-assisted surgery versus open laparotomy. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Randomized controlled trials (RCTs) and cohort studies up to June 15, 2024, were identified using PubMed, EMBASE, and Google Scholar. Additionally, reference lists of included studies, relevant review articles, and clinical guidelines were manually searched. The primary outcomes evaluated were length of stay, 90-day mortality, postoperative pancreatic fistula (POPF), and Post-pancreatectomy haemorrhage (PPH). Secondary outcomes included estimated blood loss, reoperation rate, lymph node yield, and operative time. The final analysis included 10 retrospective cohort studies involving 23,272 patients (2,179 robotic-assisted and 21,093 open surgery). There were no significant differences between the two procedures in terms of postoperative pancreatic fistula, Post-pancreatectomy haemorrhage, lymph node yield, and operative time. However, patients undergoing robotic-assisted surgery had shorter lengths of stay, lower 90-day mortality, and less estimated blood loss compared to those undergoing open surgery. The reoperation rate was higher for the robotic-assisted group. Robotic-assisted surgery for pancreatic ductal adenocarcinoma is safe and feasible. Compared to open surgery, it offers better perioperative and short-term oncologic outcomes, but with a higher risk of reoperation.
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Carcinoma Ductal Pancreático , Tempo de Internação , Pancreatectomia , Neoplasias Pancreáticas , Procedimentos Cirúrgicos Robóticos , Procedimentos Cirúrgicos Robóticos/métodos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Humanos , Carcinoma Ductal Pancreático/cirurgia , Carcinoma Ductal Pancreático/mortalidade , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/mortalidade , Pancreatectomia/métodos , Resultado do Tratamento , Tempo de Internação/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Duração da Cirurgia , Fístula Pancreática/etiologia , Fístula Pancreática/epidemiologia , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Reoperação/estatística & dados numéricos , Laparotomia/métodosRESUMO
Gas chromatography-ion mobility spectrometry (GC-IMS) is a smart method that has been applied to determine the volatile compounds in Chinese teas, but its use in comparing the volatile compounds of different types of tea has not been mentioned. In this study, the volatile compounds found in four types of samples (green, yellow, white, and black teas) made with fresh leaves of Camellia sinensis (L.) Kuntze 'Zhongcha 111' were analyzed using GC-IMS. The results showed that 93 volatile compounds were identified from our tea samples and that the average volume of aldehydes was higher than that for other compounds, especially in white tea. The different samples were successfully categorized using multivariate statistical analysis. Using partial least squares discriminant analysis (PLS-DA), we found 15 key compounds, including four differential components: (E)-2-hexenal, 2-furanmethanethio, 2-hexanol, and 1-octene. There were 29 common components, and their total content reached 386.0 µg/g. Moreover, the 3-methyl-2-butenal and dimethyl disulfide detected in the four samples were also differential compounds, varying according to the manufacturing technology. Thus, this study demonstrates that different types of teas can be discriminated easily using GC-IMS and that this is helpful to shorten the time for improving tea quality and developing new products.
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Proximity labeling proteomics (PLP) strategies are powerful approaches to yield snapshots of protein neighborhoods. Here, we describe a multiscale PLP method with adjustable resolution that uses a commercially available photocatalyst, Eosin Y, which upon visible light illumination activates different photo-probes with a range of labeling radii. We applied this platform to profile neighborhoods of the oncogenic epidermal growth factor receptor and orthogonally validated more than 20 neighbors using immunoassays and AlphaFold-Multimer prediction. We further profiled the protein neighborhoods of cell-cell synapses induced by bispecific T cell engagers and chimeric antigen receptor T cells. This integrated multiscale PLP platform maps local and distal protein networks on and between cell surfaces, which will aid in the systematic construction of the cell surface interactome, revealing horizontal signaling partners and reveal new immunotherapeutic opportunities.
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Amarelo de Eosina-(YS) , Corantes Fluorescentes , Proteômica , Coloração e Rotulagem , Humanos , Catálise , Membrana Celular/metabolismo , Membrana Celular/química , Receptores ErbB/metabolismo , Luz , Processos Fotoquímicos , Mapas de Interação de Proteínas , Proteômica/métodos , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/imunologia , Coloração e Rotulagem/métodos , Amarelo de Eosina-(YS)/química , Corantes Fluorescentes/químicaRESUMO
Mechanistic models are powerful tools for chromatographic process development and optimization. However, hydrophobic interaction chromatography (HIC) mechanistic models lack an effective and logical parameter estimation method, especially for multi-component system. In this study, a parameter-by-parameter method for multi-component system (called as mPbP-HIC) was derived based on the retention mechanism to estimate the six parameters of the Mollerup isotherm for HIC. The linear parameters (ks,i and keq,i) and nonlinear parameters (ni and qmax,i) of the isotherm can be estimated by the linear regression (LR) and the linear approximation (LA) steps, respectively. The remaining two parameters (kp,i and kkin,i) are obtained by the inverse method (IM). The proposed method was verified with a two-component model system. The results showed that the model could accurately predict the protein elution at a loading of 10 g/L. However, the elution curve fitting was unsatisfactory for high loadings (12 g/L and 14 g/L), which is mainly attributed to the demanding experimental conditions of the LA step and the potential large estimation error of the parameter qmax. Therefore, the inverse method was introduced to further calibrate the parameter qmax, thereby reducing the estimation error and improving the curve fitting. Moreover, the simplified linear approximation (SLA) was proposed by reasonable assumption, which provides the initial guess of qmax without solving any complex matrix and avoids the problem of matrix unsolvable. In the improved mPbP-HIC method, qmax would be initialized by the SLA and finally determined by the inverse method, and this strategy was named as SLA+IM. The experimental validation showed that the improved mPbP-HIC method has a better curve fitting, and the use of SLA+IM reduces the error accumulation effect. In process optimization, the parameters estimated by the improved mPbP-HIC method provided the model with excellent predictive ability and reasonable extrapolation. In conclusion, the SLA+IM strategy makes the improved mPbP-HIC method more rational and can be easily applied to the practical separation of protein mixture, which would accelerate the process development for HIC in downstream of biopharmaceuticals.
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Interações Hidrofóbicas e Hidrofílicas , Cromatografia Líquida/métodos , Modelos Lineares , Proteínas/isolamento & purificação , Proteínas/química , Proteínas/análise , Modelos QuímicosRESUMO
[This corrects the article DOI: 10.1155/2014/237067.].