RÉSUMÉ
Permeability is a key factor driving the absorption of orally administered drugs. In early discovery, the efficient evaluation of permeability, particularly for compounds violating Lipinski's Rule of 5, remains challenging. Addressing this, we established a high-throughput method to measure the experimental polar surface area (HT-EPSA) as an in vitro surrogate to measure permeability. Compared to earlier methods, HT-EPSA significantly reduces data acquisition time with enhanced sensitivity, selectivity, and data quality. In the effort of translating EPSA to human in vitro and in vivo passive permeability, we demonstrated the application of EPSA for predicting Caco-2 cell and human intestinal permeability, showing improvements over topological polar surface area and the parallel artificial membrane permeability assay for rank-ordering permeability in a proteolysis targeting chimera case study. The HT-EPSA method is expected to be highly beneficial in guiding early stage compound rank-ordering, faster decision-making, and in predicting in vitro and/or in vivo human intestinal permeability.
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To systematically explore the effects of minimally invasive plate osteosynthesis (MIPO) versus intramedullary nail (IMN) on wound infection and wound healing in patients with distal tibia fractures. A computerised search of PubMed, Web of Science, Cochrane Library, Embase, Wanfang, China Biomedical Literature Database (CBM) and China National Knowledge Infrastructure databases was performed, from their inception to October 2023, to identify relevant studies on the application of MIPO and IMN in patients with distal tibial fractures. The quality of the included literature was evaluated by two researchers based on inclusion and exclusion criteria, and basic information of the literature was collected, with wound infection, postoperative complications and wound healing time as the main indicators for analysis. Stata 17.0 software was applied for analysis. Overall, 23 papers and 2099 patients were included, including 1026 patients in the MIPO group and 1073 patients in the IMN group. The results revealed, when compared with IMN treatment, patients with distal tibia fractures who underwent MIPO treatment had a lower incidence of postoperative complications (OR = 0.33, 95% CI: 0.25-0.42, p < 0.001) and a shorter wound healing time (SMD = -1.00, 95% CI: -1.51 to -0.49, p < 0.001), but the incidence of postoperative wound infection was higher (OR = 2.01, 95% CI: 1.35-3.01, p = 0.001). Both MIPO and IMN are excellent treatments for distal tibia fractures. MIPO is effective in reducing the incidence of complications as well as shortening the time of wound healing time but increases the risk of wound infection. In clinical practice, surgeons can make individual choices based on the patient's wishes and proficiency in both techniques.
Sujet(s)
Fractures de la cheville , Ostéosynthese intramedullaire , Fractures du tibia , Humains , Ostéosynthese intramedullaire/méthodes , Consolidation de fracture , Interventions chirurgicales mini-invasives/effets indésirables , Interventions chirurgicales mini-invasives/méthodes , Ostéosynthèse interne/effets indésirables , Fractures du tibia/chirurgie , Infection de plaie opératoire/étiologie , Résultat thérapeutiqueRÉSUMÉ
Animal slurry storage is an important ammonia (NH3) emission source. Sulfuric acid (H2SO4)-modified vermiculite coverage is a new promising technology for controlling NH3 emission from slurry storage. However, the underlying mechanisms in controlling the mitigation effect remain unclear. Here, a series of experiments to determine the effect of H2SO4 on the modified vermiculite properties, floating persistence, and NH3 mitigation effect was conducted. Results showed that abundant H2SO4 and sulfate remained on the outer surface and in the extended inner pores of the vermiculite with acidifying H+ concentrations higher than 5 M. An initial strong instantaneous acidification of surface slurry released rich carbon dioxide bubbles, strengthening cover floating performance. An acidification in the vermiculite cover layer and a good coverage inhibition interacted, being the two leading mechanisms for mitigating NH3 during initial 40-50 days of storage. The bacterial-amoA gene dominated the conversion of NH3 to nitrous oxide after 50 days of storage. Vermiculite with 5 M H+ modification reduced the NH3 emissions by 90 % within the first month of slurry storage and achieved a 64 % mitigation efficiency throughout the 84 days period. With the development of the aerial spraying equipment such as agricultural drones, acidifying vermiculite coverage hold promise as an effective method for reducing NH3 emission while absorbing nutrients from liquid slurry storage tank or lagoon. This design should now be tested under field conditions.
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Silicates d'aluminium , Ammoniac , Acides sulfuriques , Animaux , Ammoniac/analyse , Agriculture , Fumier , Protoxyde d'azote/analyseRÉSUMÉ
Scrub typhus may be one of the world's most prevalent, neglected and serious, but easily treatable, febrile diseases. It has become a significant potential threat to public health in China. In this study we used national disease surveillance data to analyze the incidence and spatial-temporal distribution of scrub typhus in mainland China during 1952-1989 and 2006-2018. Descriptive epidemiological methods and spatial-temporal epidemiological methods were used to investigate the epidemiological trends and identify high-risk regions of scrub typhus infection. Over the 51-year period, a total of 182,991 cases and 186 deaths were notified. The average annual incidence was 0.13 cases/100,000 population during 1952-1989. The incidence increased sharply from 0.09/100,000 population in 2006 to 1.93/100,000 population in 2018 and then exponentially increased after 2006. The incidence was significantly higher in females than males (χ2 = 426.32, P < 0.001). Farmers had a higher incidence of scrub typhus than non-farmers (χ2 = 684.58, P < 0.001). The majority of cases each year were reported between July and November with peak incidence occurring during October each year. The trend surface analysis showed that the incidence of scrub typhus increased gradually from north to south, and from east and west to the central area. The spatial autocorrelation analysis showed that a spatial positive correlation existed in the prevalence of scrub typhus on a national scale, which had the characteristic of aggregated distribution (I = 0.533, P < 0.05). LISA analysis showed hotspots (High-High) were primarily located in the southern and southwestern provinces of China with the geographical area expanding annually. These findings provide scientific evidence for the surveillance and control of scrub typhus which may contribute to targeted strategies and measures for the government.
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Fièvre fluviale du Japon , Mâle , Femelle , Humains , Fièvre fluviale du Japon/épidémiologie , Saisons , Analyse spatiale , Incidence , Chine/épidémiologieRÉSUMÉ
The objective of this paper is to gain insights into the synergistic advantage of anaerobic co-fermentation of heat-treated sludge (HS) with food waste (FW) and heat-treated food waste (HFW) for hydrogen production. The results showed that, compared with raw sludge (RS) mixed with FW (RS-FW), the co-substrate of HS mixed with either FW (HS-FW) or HFW (HS-HFW) effectively promoted hydrogen production, with HS-HFW promoted more than HS-FW. The maximum specific hydrogen production (MSHP) and the maximum hydrogen concentration (MHC) of HS-HFW were 40.53 mL H2/g dry weight and 57.22%, respectively, and 1.21- and 1.45-fold as high as those from HS-FW. The corresponding fermentation was ethanol type for HS-HFW and butyric acid type for HS-FW. The net energy production from RS-FW and HS-FW was both negative, but it was positive (2.57 MJ) from 40% HFW addition to HS-HFW. Anaerobic fermentation was more viable for HS-HFW.
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Élimination des déchets , Eaux d'égout , Fermentation , , Anaérobiose , Bioréacteurs , Aliments , Température élevée , HydrogèneRÉSUMÉ
Following the highly successful Chinese American Society for Mass Spectrometry (CASMS) conferences in the previous 2 years, the 3rd CASMS Conference was held virtually on August 28-31, 2023, using the Gather.Town platform to bring together scientists in the MS field. The conference offered a 4-day agenda with a scientific program consisting of two plenary lectures, and 14 parallel symposia in which a total of 70 speakers presented technological innovations and their applications in proteomics and biological MS and metabo-lipidomics and pharmaceutical MS. In addition, 16 invited speakers/panelists presented at two research-focused and three career development workshops. Moreover, 86 posters, 12 lightning talks, 3 sponsored workshops, and 11 exhibitions were presented, from which 9 poster awards and 2 lightning talk awards were selected. Furthermore, the conference featured four young investigator awardees to highlight early-career achievements in MS from our society. The conference provided a unique scientific platform for young scientists (i.e. graduate students, postdocs, and junior faculty/investigators) to present their research, meet with prominent scientists, learn about career development, and job opportunities (http://casms.org).
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Spectrométrie de masse , Lipidomique , Préparations pharmaceutiques , Protéomique , Congrès comme sujetRÉSUMÉ
Macrophages are heterogenic phagocytic cells that play distinct roles in physiological and pathological processes. Targeting different types of macrophages has shown potent therapeutic effects in many diseases. Although many approaches are developed to target anti-inflammatory macrophages, there are few researches on targeting pro-inflammatory macrophages, which is partially attributed to their non-s pecificity phagocytosis of extracellular substances. In this study, a novel recombinant protein is constructed that can be anchored on an exosome membrane with the purpose of targeting pro-inflammatory macrophages via antigen recognition, which is named AnCar-ExoLaIMTS . The data indicate that the phagocytosis efficiencies of pro-inflammatory macrophages for different AnCar-ExoLaIMTS show obvious differences. The AnCar-ExoLaIMTS3 has the best targeting ability for pro-inflammatory macrophages in vitro and in vivo. Mechanically, AnCar-ExoLaIMTS3 can specifically recognize the leucine-rich repeat domain of the TLR4 receptor, and then enter into pro-inflammatory macrophages via the TLR4-mediated receptor endocytosis pathway. Moreover, AnCar-ExoLaIMTS3 can efficiently deliver therapeutic cargo to pro-inflammatory macrophages and inhibit the synovial inflammatory response via downregulation of HIF-1α level, thus ameliorating the severity of arthritis in vivo. Collectively, the work established a novel gene/drug delivery system that can specifically target pro-inflammatory macrophages, which may be beneficial for the treatments of arthritis and other inflammatory diseases.
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Arthrite , Macrophages , Humains , Macrophages/métabolisme , Arthrite/traitement médicamenteux , Phagocytose , Anti-inflammatoires/usage thérapeutique , Communication cellulaireRÉSUMÉ
RNA interference (RNAi) is a powerful tool that post-transcriptionally silences target genes in eukaryotic cells. However, silencing efficacy varies greatly among different insect species. Recently, we met with little success when attempting to knock down genes in the mirid bug Apolygus lucorum via dsRNA injection. The disappearance of double-stranded RNA (dsRNA) could be a potential factor that restricts RNAi efficiency. Here, we found that dsRNA can be degraded in midgut fluids, and a dsRNase of A. lucorum (AldsRNase) was identified and characterized. Sequence alignment indicated that its 6 key amino acid residues and the Mg2+ -binding site were similar to those of other insects' dsRNases. The signal peptide and endonuclease non-specific domain shared high sequence identity with the brown-winged green stinkbug Plautia stali dsRNase. AldsRNase showed high salivary gland and midgut expression and was continuously expressed through the whole life cycle, with peaks at the 4th instar ecdysis in the whole body. The purified AldsRNase protein obtained by heterologously expressed can rapidly degrade dsRNA. When comparing the substrate specificity of AldsRNase, 3 specific substrates (dsRNA, small interfering RNA, and dsDNA) were all degraded, and the most efficient degradation is dsRNA. Subsequently, immunofluorescence revealed that AldsRNase was expressed in the cytoplasm of midgut cells. Through cloning and functional study of AldsRNase, the enzyme activity and substrate specificity of the recombinant protein, as well as the subcellular localization of nuclease, the reason for the disappearance of dsRNA was explained, which was useful in improving RNAi efficiency in A. lucorum and related species.
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Heteroptera , ARN double brin , Animaux , ARN double brin/génétique , Alignement de séquences , Interférence par ARN , Insectes/génétique , Clonage moléculaire , Heteroptera/génétiqueRÉSUMÉ
Disease represents a major problem in sustainable agricultural development. Plants interact closely with various microorganisms during their development and in response to the prevailing environment. In particular, pathogenic microorganisms can cause plant diseases, affecting the fertility, yield, and longevity of plants. During the long coevolution of plants and their pathogens, plants have evolved both molecular pattern-triggered immunity (PTI) and effector-triggered immunity (ETI) signaling networks in order to regulate host cells in response to pathogen infestation. Additionally, in the postgenomic era, alternative splicing (AS) has become uncovered as one of the major drivers of proteome diversity, and abnormal RNA splicing is closely associated with bacterial infections. Currently, the complexity of host-bacteria interactions is a much studied area of research that has shown steady progress over the past decade. Although the development of high-throughput sequencing technologies and their application in transcriptomes have revolutionized our understanding of AS, many mechanisms related to host-bacteria interactions remain still unclear. To this end, this review summarizes the changes observed in AS during host-bacteria interactions and outlines potential therapeutics for bacterial diseases based on existing studies. In doing so, we hope to provide guidelines for plant disease management in agriculture.
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The 16th Workshop on Recent Issues in Bioanalysis (16th WRIB) took place in Atlanta, GA, USA on September 26-30, 2022. Over 1000 professionals representing pharma/biotech companies, CROs, and multiple regulatory agencies convened to actively discuss the most current topics of interest in bioanalysis. The 16th WRIB included 3 Main Workshops and 7 Specialized Workshops that together spanned 1 week in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on ICH M10 BMV final guideline (focused on this guideline training, interpretation, adoption and transition); mass spectrometry innovation (focused on novel technologies, novel modalities, and novel challenges); and flow cytometry bioanalysis (rising of the 3rd most common/important technology in bioanalytical labs) were the special features of the 16th edition. As in previous years, WRIB continued to gather a wide diversity of international, industry opinion leaders and regulatory authority experts working on both small and large molecules as well as gene, cell therapies and vaccines to facilitate sharing and discussions focused on improving quality, increasing regulatory compliance, and achieving scientific excellence on bioanalytical issues. This 2022 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2022 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 2) covers the recommendations on LBA, Biomarkers/CDx and Cytometry. Part 1 (Mass Spectrometry and ICH M10) and Part 3 (Gene Therapy, Cell therapy, Vaccines and Biotherapeutics Immunogenicity) are published in volume 15 of Bioanalysis, issues 16 and 14 (2023), respectively.
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Dosage biologique , Rapport de recherche , Cytométrie en flux/méthodes , Ligands , Marqueurs biologiques/analyse , Dosage biologique/méthodesRÉSUMÉ
Nanobio interaction studies have generated a significant amount of data. An important next step is to organize the data and design computational techniques to analyze the nanobio interactions. Here we developed a computational technique to correlate the nanoparticle spatial distribution within heterogeneous solid tumors. This approach led to greater than 88% predictive accuracy of nanoparticle location within a tumor tissue. This proof-of-concept study shows that tumor heterogeneity might be defined computationally by the patterns of biological structures within the tissue, enabling the identification of tumor patterns for nanoparticle accumulation.
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Nanoparticules , Tumeurs , Humains , Nanoparticules/composition chimiqueRÉSUMÉ
Coronavirus disease (COVID-19) has disrupted health, economy, and society globally. Thus, many countries, including China, have adopted lockdowns to prevent the epidemic, which has limited human activities while affecting air quality. These affects have received attention from academics, but very few studies have focused on western China, with a lack of comparative studies across lockdown periods. Accordingly, this study examines the effects of lockdowns on air quality and pollution, using the hourly and daily air monitoring data collected from Lanzhou, a large city in Northwest China. The results indicate an overall improvement in air quality during the three lockdowns compared to the average air quality in the recent years, as well as reduced PM2.5, PM10, SO2, NO2, and CO concentrations with different rates and increased O3 concentration. During lockdowns, Lanzhou's "morning peak" of air pollution was alleviated, while the spatial characteristics remained unchanged. Further, ordered multi-classification logistic regression models to explore the mechanisms by which socioeconomic backgrounds and epidemic circumstances influence air quality revealed that the increment in population density significantly aggravated air pollution, while the presence of new cases in Lanzhou, and medium- and high-risk areas in the given district or county both increase the likelihood of air quality improvement in different degrees. These findings contribute to the understanding of the impact of lockdown on air quality, and propose policy suggestions to control air pollution and achieve green development in the post-epidemic era.
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Plant virual infections are mainly caused by plant-virus parasitism which affects ecological communities. Some viruses are highly pathogen specific that can infect only specific plants, while some can cause widespread harm, such as tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV). After a virus infects the host, undergoes a series of harmful effects, including the destruction of host cell membrane receptors, changes in cell membrane components, cell fusion, and the production of neoantigens on the cell surface. Therefore, competition between the host and the virus arises. The virus starts gaining control of critical cellular functions of the host cells and ultimately affects the fate of the targeted host plants. Among these critical cellular processes, alternative splicing (AS) is an essential posttranscriptional regulation process in RNA maturation, which amplify host protein diversity and manipulates transcript abundance in response to plant pathogens. AS is widespread in nearly all human genes and critical in regulating animal-virus interactions. In particular, an animal virus can hijack the host splicing machinery to re-organize its compartments for propagation. Changes in AS are known to cause human disease, and various AS events have been reported to regulate tissue specificity, development, tumour proliferation, and multi-functionality. However, the mechanisms underlying plant-virus interactions are poorly understood. Here, we summarize the current understanding of how viruses interact with their plant hosts compared with humans, analyze currently used and putative candidate agrochemicals to treat plant-viral infections, and finally discussed the potential research hotspots in the future. This article is categorized under: RNA Processing > Splicing Mechanisms RNA Processing > Splicing Regulation/Alternative Splicing.
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Eucaryotes , Virus , Humains , Animaux , Épissage alternatif , Maladies des plantesRÉSUMÉ
Large variabilities in ammonia (NH3) released from animal manure and emitted from different livestock buildings were frequently reported, but the factors influencing the emissions were not sufficiently investigated. In this paper, continuously monitored data of NH3 emissions and other relevant environmental variables under controlled conditions in a 12-room experimental swine building for a 155-d complete wean-to-finish cycle were studied. Measurement data mining was conducted at both spatial and temporal dimensions using panel data analysis with heterogeneous time trends. The pig diet, total pig weight, and the pit air temperature were identified as the major influencing factors for the variabilities by using multivariate linear regression. Two unidentified factors that imposed substantial influences on the NH3 emission variabilities were predicted. They were most possibly related to variations in microenvironment and microbial activity inside the manure in the pit. The results suggest necessary future research to identify physical properties of the new NH3 emissions factors in microbiological and biochemical processes.
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Ammoniac , Fumier , Suidae , Animaux , Ammoniac/analyse , Fumier/analyse , Régime alimentaireRÉSUMÉ
Implantable tubes, shunts, and other medical conduits are crucial for treating a wide range of conditions from ears and eyes to brain and liver but often impose serious risks of device infection, obstruction, migration, unreliable function, and tissue damage. Efforts to alleviate these complications remain at an impasse because of fundamentally conflicting design requirements: Millimeter-scale size is required to minimize invasiveness but exacerbates occlusion and malfunction. Here, we present a rational design strategy that reconciles these trade-offs in an implantable tube that is even smaller than the current standard of care. Using tympanostomy tubes (ear tubes) as an exemplary case, we developed an iterative screening algorithm and show how unique curved lumen geometries of the liquid-infused conduit can be designed to co-optimize drug delivery, effusion drainage, water resistance, and biocontamination/ingrowth prevention in a single subcapillary-length-scale device. Through extensive in vitro studies, we demonstrate that the engineered tubes enabled selective uni- and bidirectional fluid transport; nearly eliminated adhesion and growth of common pathogenic bacteria, blood, and cells; and prevented tissue ingrowth. The engineered tubes also enabled complete eardrum healing and hearing preservation and exhibited more efficient and rapid antibiotic delivery to the middle ear in healthy chinchillas compared with current tympanostomy tubes, without resulting in ototoxicity at up to 24 weeks. The design principle and optimization algorithm presented here may enable tubes to be customized for a wide range of patient needs.
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Otite moyenne sécrétoire , Humains , Otite moyenne sécrétoire/diagnostic , Ventilation de l'oreille moyenne/méthodes , Oreille moyenne/anatomopathologie , Prothèses et implants , AntibactériensRÉSUMÉ
In contrast to quantification of biotherapeutics, endogenous protein biomarker and target quantification using LC-MS based targeted proteomics can require a much more stringent and time-consuming tryptic signature peptide selection for each specific application. While some general criteria exist, there are no tools currently available in the public domain to predict the ionization efficiency for a given signature peptide candidate. Lack of knowledge of the ionization efficiencies forces investigators to choose peptides blindly, thus hindering method development for low abundant protein quantification. Here, the authors propose a tryptic signature peptide selection workflow to achieve a more efficient method development and to improve success rates in signature peptide selection for low abundant endogenous target and protein biomarker quantification.
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Protéomique , Spectrométrie de masse en tandem , Chromatographie en phase liquide , Flux de travaux , Peptides , Marqueurs biologiquesRÉSUMÉ
While bioanalytical outsourcing is widely adopted in the pharmaceutical industry, AbbVie is one of the few large biopharmaceutical companies having an internal bioanalytical unit to support nearly all its drug metabolism and pharmacokinetic studies. This article highlights our experience and perspective in building an integrated and centralized laboratory to provide early discovery and preclinical-stage bioanalytical support with high operational efficiency, cost-effectiveness and data integrity. The advantages of in-house nonregulated bioanalytical support include better control of data quality, faster turnaround times, real-time knowledge sharing and troubleshooting, and lower near- and long-term costs. The success of an in-house model depends upon a comprehensively optimized and streamlined workflow, fueled by continuous improvements and implementation of innovative technologies.
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Laboratoires , Services externalisés , Automatisation , Technologie , Industrie pharmaceutiqueRÉSUMÉ
In order to solve the limitation of tumor microenvironment on the anticancer effect of nanozymes, a multifunctional nanoenzyme Co/La-PB@MOF-199/GOx was designed in this work. By doping Co2+ and La3+ in different proportions, Co/La-PB with the optimal photothermal-enhanced catalytic performance was screened, which can catalyze H2O2 to generate more hydroxyl radicals (â¢OH) and oxygen, showing peroxidase (POD)-like and catalase(CAT)-like property. Through MOF-199 coating and loading glucose oxidase (GOx), a multifunctional nanoenzyme Co/La-PB@MOF-199/GOx was achieved. Due to the pH response of MOF-199, GOx can be accurately released into tumors to catalyze the reaction of glucose and oxygen to produce H2O2. In this process, the oxygen consumption can be compensated by the CAT-like property to realize continuous consumption of glucose and self-supply of H2O2 to continuously produce â¢OH. In the presence of high oxidation state metal ions (Co3+ and Fe3+), GSH consumption is accelerated to avoid weakening of â¢OH, showing the glutathione oxidase (GPx-like) activity. Besides, magnetic resonance imaging (MRI) experiments showed the potential application in imaging guided therapy. In vivo anti-tumor experiments showed a satisfactory anti-cancer effect through multi-enzymatic activities.
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Peroxyde d'hydrogène , Tumeurs , Humains , Tumeurs/thérapie , Glucose , Glucose oxidase , Oxygène , Microenvironnement tumoralRÉSUMÉ
RATIONALE: The in-sample calibration curve (ISCC) approach of quantification utilizes the response of isotopologue ions from spiked-in stable isotope labeled internal standard (SIL-IS) to build a standard curve. The quantitative analysis of the study sample is achieved based on the response of selected monoisotopic analyte ion against the calibration curve. Although this methodology has been demonstrated to be feasible by unit and high-resolution mass spectrometers, quantitation on high-resolution mass spectrometer with product ions has not been tested. We tested the feasibility of this approach using product ions on an high-resolution mass spectrometer equipped with an Orbitrap detector. METHODS: Using a proteomics workflow for sample preparation, two surrogate peptides were quantified from a complex matrix of protein digest from human peripheral blood mononuclear cells (hPBMCs). SIL-IS was spiked in at different levels to construct calibration curves in a traditional manner. ISCCs were prepared using extracted ion chromatograms from isotopically resolved mass spectra and compared with traditional calibration curves. RESULTS: A linear response was observed with ISCC approach for at least two to three orders of magnitude in MS1 as well as targeted MS2 (tMS2). From protein digests, isobaric interferences were observed for endogenous peptides on the MS1 level; this was circumvented with product-ion-based quantitation where for one peptide, %CV for endogenous levels was more than 20% with ISCC but higher with the traditional calibration curve approach. For the second peptide, endogenous levels could not be determined in the traditional approach as calibrant levels did not bracket the lower end, and with the ISCC approach, isotopologues at abundances lower than the endogenous level allowed for quantitative assessments. CONCLUSIONS: ISCC demonstrated improved precision across surrogate peptides from endogenous protein digests. In samples where endogenous analyte concentrations were low in abundance, ISCC rescued what would have been a non-reportable result in a traditional bioanalytical assay as calibrant levels were not prepared at adequately low levels to bracket unknowns. ISCC using high-resolution mass spectrometer is feasible and ideal compared to unit resolution mass spectrometers. High-resolution mass spectrometer allows for isotopic resolution for analytes with > + 2 charge state and provides flexibility in quantification using multiple product ions. ISCC using high-resolution mass spectrometer allows for simultaneous assaying of low abundance isotopologues, the signal acquisition of which is not constrained by limits in data acquisition or calibrant preparation as with other approaches but rather limited by platform sensitivity. In contrast to unit resolution mass spectrometers, these features offered by high-resolution mass spectrometer could be especially useful for the drug discovery assay support where there is less lead time for assay development than for the assays to support the drug development studies.