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The success of arsenic in acute promyelocytic leukemia (APL) treatment is hardly transferred to non-APL cancers, mainly due to the low selectivity and weak binding affinity of traditional arsenicals to oncoproteins critical for cancer survival. We present herein the reinvention of aliphatic trivalent arsenicals (As) as reversible covalent warheads of As-based targeting inhibitors toward Bruton's tyrosine kinase (BTK). The effects of As warheads' valency, thiol protection, methylation, spacer length, and size on inhibitors' activity were studied. We found that, in contrast to the bulky and rigid aromatic As warhead, the flexible aliphatic As warheads were well compatible with the well-optimized guiding group to achieve nanomolar inhibition against BTK. The optimized As inhibitors effectively blocked the BTK-mediated oncogenic signaling pathway, leading to elevated antiproliferative activities toward lymphoma cells and xenograft tumor. Our study provides a promising strategy enabling rational design of new aliphatic arsenic-based reversible covalent inhibitors toward non-APL cancer treatment.
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Arsênio , Arsenicais , Leucemia Promielocítica Aguda , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Arsenicais/farmacologia , Arsenicais/uso terapêutico , Arsênio/farmacologia , Tirosina Quinase da Agamaglobulinemia , Transdução de Sinais , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêuticoRESUMO
Early diagnosis is paramount for enhancing survival rates and prognosis in the context of malignant diseases. Hepatocellular carcinoma (HCC), the second leading cause of cancer-related deaths worldwide, poses significant challenges for its early detection. In this study, we present an innovative approach which contributed to the early diagnosis of HCC. By lanthanide encoding signal amplification to map glycan-linkages at the single-cell level, the minute quantities of "soft" glycan-linkages on single cell surface were converted into "hard" elemental tags through the use of an MS2 signal amplifier. Harnessing the power of lanthanides encoded within MS2, we achieve nearly three orders of magnitude signal amplification. These encoded tags are subsequently quantified using single-cell inductively coupled plasma mass spectrometry (SC-ICP-MS). Linear discriminant analysis (LDA) identifies seven specific glycan-linkages (α-2,3-Sia, α-Gal, α-1,2-Fuc, α-1,6-Fuc, α-2,6-Sia, α-GalNAc, and Gal-ß-1,3-GalNAc) as biomarkers. Our methodology is initially validated at the cellular level with 100% accuracy in discriminating between hepatic carcinoma HepG2 cells and their normal HL7702 cells. We apply this approach to quantify and classify glycan-linkages on the surfaces of 55 clinical surgical HCC specimens. Leveraging these seven glycan-linkages as biomarkers, we achieve precise differentiation between 8 normal hepatic specimens, 40 early HCC specimens, and 7 colorectal metastasis HCC specimens. This pioneering work represents the first instance of employing single-cell glycan-linkages as biomarkers promising for the early diagnosis of HCC with a remarkable 100% predictive accuracy rate, which holds immense potential for enhancing the feasibility and precision of HCC diagnosis in clinical practice.
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Carcinoma Hepatocelular , Elementos da Série dos Lantanídeos , Neoplasias Hepáticas , Espectrometria de Massas , Polissacarídeos , Análise de Célula Única , Carcinoma Hepatocelular/diagnóstico , Humanos , Neoplasias Hepáticas/diagnóstico , Polissacarídeos/análise , Polissacarídeos/química , Elementos da Série dos Lantanídeos/química , Espectrometria de Massas/métodos , Análise de Célula Única/métodos , Detecção Precoce de Câncer/métodos , Células Hep G2 , Biomarcadores Tumorais/análiseRESUMO
BACKGROUND: Mutations in MPZL2, the characteristic genetic etiology of autosomal recessive deafness loci 111 (DFNB111), cause non-syndromic and moderate sensorineural hearing loss. METHODS: In this study, we analyzed the phenotype and genotype of eight pedigrees consisting of 10 hearing loss patients with bi-allelic pathogenic or likely pathogenic variants in MPZL2. These patients were identified from a 3272 Chinese patient cohort who underwent genetic testing. RESULTS: Apart from symmetrical and moderate sensorineural hearing loss, the MPZL2-related phenotype was characterized by progressive hearing loss with variation in the onset age (congenital defect to onset at the young adult stage). We determined that in the Chinese population, the genetic load of MPZL2 defects was 0.24% (8/3272) in patients diagnosed with hearing loss and 7.02% (8/114) in patients diagnosed with hereditary moderate sensorineural hearing loss caused by STRC, OTOA, OTOG, OTOGL, TECTA, MPZL2 and others. Three known MPZL2 variants (c.220C > T (p.Gln74*), c.68delC (p.Pro23Leufs*2), c.463delG (p.Ala155Leufs*10)) and a novel start loss variant (c.3G > T (p.Met1?)) were identified. MPZL2 c.220C > T was identified as the hotspot variant in the Chinese population and even in East Asia compared with c.72delA (p.Ile24Metfs*22) in European and West Asia through allele frequency. CONCLUSIONS: We concluded that apart from moderate HL, progressive HL is another character of MPZL2-related HL. No specified variant was verified for the progression of HL, the penetrance and expressivity cannot be determined yet. A novel MPZL2 variant at the start codon was identified, enriching the variant spectrum of MPZL2. The hotspot variants of MPZL2 vary in different ethnicities. This study provides valuable data for the diagnosis, prognosis evaluation and genetic counseling of patients with moderate sensorineural hearing loss related to MPZL2.
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Surdez , Perda Auditiva Neurossensorial , Humanos , Adulto Jovem , Povo Asiático/genética , Moléculas de Adesão Celular , China , Surdez/etnologia , Surdez/genética , Perda Auditiva Neurossensorial/etnologia , Perda Auditiva Neurossensorial/genética , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas de MembranaRESUMO
With the expansion of ICP-MS application into the field of bioanalysis, there is an urgent need for novel element tags today. Here, we report the design of a dual-element Ir-Eu tag, opening the door to simultaneous fluorescent imaging and ICP-MS quantification. The ratio of 153Eu/193Ir may serve as a precision control of the labeling process, allowing internal validation of the quantitative results obtained. As for SIRPα and its host cell analysis exemplified here, the Ir-Eu tag demonstrated superior figures of ICP-MS quantification with the LOD (3σ) down to 0.5 (153Eu) and 1.1 (193Ir) pM SIRPα and 220 (153Eu) and 830 (193Ir) RAW264.7 cells more than 130 times more sensitive compared with the LOD (3σ) of 65.2 pM SIRPα at 612 nm using fluorometry. Not limited to these demonstrations, we believe that the design ideas of the dual Ir-Eu tags should be applicable to various cases of bioanalysis when dual optical profiling and ICP-MS quantification are indispensable.
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Espectrometria de Massas , Fluorometria , Espectrometria de Massas/métodos , Análise Espectral , Irídio/química , Európio/química , Corantes Fluorescentes/química , Animais , Camundongos , Receptores Imunológicos/análise , Receptores Imunológicos/química , Células RAW 264.7RESUMO
Background: Cochlear implantation (CI) outcomes in patients with auditory neuropathy (AN) are variable, which hampers patients' decisions on CI. Objective: This study aims to assess the outcomes of CI in individuals diagnosed with AN and to examine the various factors that may influence the effectiveness of this intervention. Methods: A total of 75 patients diagnosed with AN were included in the study. The hearing threshold, the score of categories of auditory performance (CAP), speech intelligibility rating (SIR), and speech audiometry were tested. Genetic testing was conducted by medical exome sequencing in 46 patients. Results: After CI, the average aided hearing threshold for patients with prelingual and post-lingual onset was 38.25 ± 6.63 dB and 32.58 ± 9.26 dB, respectively; CAP score improved to 5.52 ± 1.64 (p < 0.001) and 6.00 ± 0.96 (p < 0.001), respectively; SIR score increased to 3.57 ± 1.22 (p < 0.001) and 4.15 ± 0.95 (p < 0.001), respectively. Maximum speech recognition ranged from 58 to 93% for prelingual onset patients and 43 to 98% for those with post-lingual onset. Speech outcomes of CI in cases with cochlear nerve (CN) deficiency were significantly poorer (p = 0.008). Molecular etiologies, including TWIST1, ACTG1, m.A7445G, and a copy-number variant (CNV) carrying ACTB, were related to AN here. Conclusion: CI is a viable therapy option for patients with AN; CN deficiency might impact outcomes of CI.
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Coffin-Siris syndrome (CSS, OMIM#135900) is a rare congenital disorder associated with neurodevelopmental and dysmorphic features. The primary cause of CSS is pathogenic variants in any of 9 BAF chromatin-remodeling complex encoding genes or the genes SOX11 and PHF6. Herein, we performed whole-exome sequencing (WES) and a series of analyses of growth-related, auditory, and radiological findings in two probands with syndromic sensorineural hearing loss and inner ear malformations who exhibited distinctive facial features, intellectual disability, growth retardation, and fifth finger malformation. Two de novo variants in the SOX11 gene (c.148A>C:p.Lys50Asn; c.811_814del:p.Asn271Serfs*10) were detected in these probands and were identified as pathogenic variants as per ACMG guidelines. These probands were diagnosed as having CSS based upon clinical and genetic findings. This is the first report of CSS caused by variants in SOX11 gene in Chinese individuals. Deleterious SOX11 variants can result in sensorineural hearing loss with inner ear malformation, potentially extending the array of phenotypes associated with these pathogenic variants. We suggest that both genetic and clinical findings be considered when diagnosing syndromic hearing loss.
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Deformidades Congênitas da Mão , Perda Auditiva Neurossensorial , Deficiência Intelectual , Micrognatismo , Humanos , Micrognatismo/diagnóstico , Micrognatismo/genética , Deformidades Congênitas da Mão/diagnóstico , Deformidades Congênitas da Mão/genética , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Pescoço/anormalidades , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/genética , Fatores de Transcrição SOXC/genéticaRESUMO
The chromatography-mass spectrometry hyphenated technique is the most widely adopted tool for quantifying trace analytes in a complex biosample. One issue we frequently encountered, however, is that the separated analyte-containing chromatographic peaks broaden and even remix prior to mass spectrometric quantification due to the inevitable molecular diffusion within the dead-volume introduced by hyphenation. We developed a zero-interfacing approach for coupling microbore (µ) HPLC with inductively coupled plasma mass spectrometry (ICPMS). Zero-interfacing µHPLC to ICPMS has been achieved by a column-nebulizer assembly (COL-NEB) of a self-designed glass framework with a tapered nozzle, in which a capillary chromatographic column can be harbored while an Ar gas flow is blown through the nozzle mouth. The COL-NEB can be positioned just before the base of the Ar-ICP serving as the central sampling channel of a conventional Ar-ICP torch for online nebulization and transportation of the analytes separated on µHPLC into ICPMS, maintaining the molecular resolution obtained on µHPLC and the limit of detection (LOD) of ICPMS. For example, the full width at half-maximum of a SLUGT peptide chromatographic peak was reduced to 1.71 ± 0.07 s (n = 5) with a 0.72 fg LOD (3σ) of 80Se. Moreover, at least 32 Se-containing peptides were determined in the trypsin lysate of the water-soluble fraction (≥3000 MW) from Se-enriched yeast CRM SELM-1 within a 10 min run, the highest record to date. We believe such an approach paves the way to determining accurate information on a heteroatom and its binding biomolecules that play key roles during life processes.
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Peptídeos , Espectrometria de Massas/métodos , Cromatografia Líquida de Alta Pressão/métodos , Análise Espectral , Peptídeos/química , Limite de DetecçãoRESUMO
Selenium (Se) is a mysterious thus tempting element playing a dual bio-chemical function, mainly through selenol, during life processes. Quantification of the selenols is thus of great significance for understanding the biological roles of Se, but remains a big challenge. Herein we report a selenol-specific recognition-mediated and europium (Eu) signal-switched amplification inductively coupled plasma mass spectrometry (ICP-MS) approach for quantifying the free active selenols (act-SeH) in cells. A bifunctional molecule, 2,4-dinitrobenzenesulfonyl-piperidin-4-yl-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic europium (DNBS-DOTA-Eu), was designed and synthesized for the specific recognition and highly sensitive quantification of act-SeH via switching Se to more sensitive Eu ICP-MS signals. The limit of detection (LOD, 3σ) of 3.41 pg/mL (22.43 pmol/L), corresponding to the absolute mass LOD of 6.82 ag act-SeH per cell, is almost 25 times lower than 83.76 pg/mL (1.06 nmol/L), 167.52 ag, when monitoring 80Se. The results indicate that act-SeH in the selenite-precultured cancerous HepG2 and paracancerous HL7702 cells are 0.090 ± 0.002 pg/cell (n = 7) and 0.021 ± 0.006 pg/cell (n = 7), more than 4.28 times higher in HepG2 than in HL7702. Preliminary application of this approach to the cells from real hepatic tissue samples suggested that act-SeH has a positive relationship with the degree of hepatic disease. act-SeH in cells appears to be a very promising relevant index for understanding the biochemical functions of Se, besides the total Se in cells and blood serum and/or plasma.
Assuntos
Európio/química , Espectrometria de Massas/métodos , Compostos de Selênio/química , Linhagem Celular , Humanos , Estrutura Molecular , Compostos Organometálicos/químicaRESUMO
Hearing loss (HL) is one of the most common disabilities in the world. In industrialized countries, HL occurs in 1-2/1,000 newborns, and approximately 60% of HL is caused by genetic factors. Next generation sequencing (NGS) has been widely used to identify many candidate genes and variants in patients with HL, but the data are scattered in multitudinous studies. It is a challenge for scientists, clinicians, and biologists to easily obtain and analyze HL genes and variant data from these studies. Thus, we developed a one-stop database of HL-related genes and variants, Gene4HL (http://www.genemed.tech/gene4hl/), making it easy to catalog, search, browse and analyze the genetic data. Gene4HL integrates the detailed genetic and clinical data of 326 HL-related genes from 1,608 published studies, along with 62 popular genetic data sources to provide comprehensive knowledge of candidate genes and variants associated with HL. Additionally, Gene4HL supports the users to analyze their own genetic engineering network data, performs comprehensive annotation, and prioritizes candidate genes and variations using custom parameters. Thus, Gene4HL can help users explain the function of HL genes and the clinical significance of variants by correlating the genotypes and phenotypes in humans.
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Portable analytical instruments find extensive application in on-site examination because of their significant advantages: these instruments are convenient and easy-to-carry, leading to high time-effectiveness, and involve low reagent consumption. We report a portable micro-liquid chromatograph (p-µLC) that was designed and fabricated in our laboratory. The p-µLC integrates homemade dual large-thrust syringe pumps for delivering the mobile phase, a capillary polymer monolithic column as the stationary phase for the separation of the target analytes, and a specially designed dual-functional optical-fiber microflow-cell for online detection. The dual-thrust syringe pumps can realize isocratic and/or gradient elution as well as reloading of the mobile phase, with flow rates ranging from 0.025 µL/min to 5.6 mL/min and the maximum working pressure of 4.5 MPa. The polymethacrylate based C-18 monolithic column facilitates the separation of small organic molecules and biomacromolecules. A homemade high-power light emission diode (LED) light source and a modified xenon flash lamp are assembled as the light source module. The dual-functional detector consists of an optical fiber microflow-cell with a self-focusing lens and a light-guiding capillary, light source module, and a small-sized grating spectrometer with an output wavelength range of 400-680 nm for the LED light source and 220-700 nm for the xenon flash lamp, enabling online detection of the absorption and fluorescence spectra of the analytes from 220 to 700 nm. A bifurcated optical fiber bundle is prepared and used to connect the light source, microflow-cell, and grating spectrometer so that the incident light leading-in and the fluorescence/scatting light leading-out can be realized simultaneously. The junction end of the bifurcated optical fiber bundles connects to one end of the light path of the microflow-cell, and a straight-through optical fiber connects another end of the microflow-cell. In the UV-Vis absorption mode, the straight-through optical fiber reads out the transmitted light, while in the fluorescence mode, the excitation light beam from the light source irradiates the sample solution in the flow-cell via one branch of the bifurcated optic fiber bundles. The fluorescence leading-out via the other branch of the bifurcated optical fiber bundles in the opposite direction of the excitation light beam is read out by the spectrometer. All the large-thrust syringe pumps and flow-path, capillary monolithic column, and optical fiber mediated flow-cell detection as well as controlling modules are installed in a suitcase with a total weight of less than 8 kg. The p-µLC is powered by DC 12V 3A or 18650 lithium battery pack and controlled by a panel computer with a custom-built windows-based chromatography workstation software for data acquisition. When using the home-made polymethacrylate based C-18 monolithic capillary column (530 µm ID×200 mm in length), the mixed alkylbenzenes can be separated and detected in an isocratic elution mode. The separation efficiency is comparable to that obtained with a commercially available HPLC.
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Polímeros , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Indicadores e ReagentesRESUMO
Although circulating tumor cells (CTCs) have great potential to act as the mini-invasive liquid biopsy cancer biomarker, a rapid and sensitive CTC detection method remains lacking. CRISPR-Cas12a has recently emerged as a promising tool in biosensing applications with the characteristic of fast detection, easy operation, and high sensitivity. Herein, we reported a CRISPR-Cas12a-based CTC detection sensor that is regulated by the multivalent duplexed-aptamer networks (MDANs). MDANs were synthesized on a magnetic bead surface by rolling circle amplification (RCA), which contain multiple duplexed-aptamer units that allow structure switching induced by cell-binding events. The presence of target cells can trigger the release of free "activator DNA" from the MDANs structure to activate the downstream CRISPR-Cas12a for signal amplification. Furthermore, the 3D DNA network formed by RCA products also provided significantly higher sensitivity than the monovalent aptamer. As a proof-of-concept study, we chose the most widely used sgc8 aptamer that specifically recognizes CCRF-CEM cells to validate the proposed approach. The MDANs-Cas12a system could afford a simple and fast CTC detection workflow with a detection limit of 26 cells mL-1. We also demonstrated that the MDANs-Cas12a could directly detect the CTCs in human blood samples, indicating a great potential of the MDANs-Cas12a in clinical CTC-based liquid biopsy.
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Técnicas Biossensoriais , Células Neoplásicas Circulantes , Sistemas CRISPR-Cas/genética , DNA , Humanos , Separação Imunomagnética , OligonucleotídeosRESUMO
Cochlear implantation (CI) is a safe and beneficial surgery for children with congenital inner ear malformations, with the exception of cochlear nerve aplasia. The combination of microtia with middle and inner ear abnormalities is extremely uncommon and sufficiently severe to make a surgical approach to the cochlea difficult. We report herein the case of a 2-year-old girl who presented with profound bilateral sensorineural hearing loss, congenital aural atresia, microtia, and inner ear malformations. High-resolution computed tomography revealed poor development of the bilateral middle ear spaces, absence of the incus and stapes, aberrant courses of facial nerves, aplastic lateral semicircular canals, and covered round windows. With intraoperative imaging assistance, sequential bilateral CI was performed using a transmastoid approach with no complication. We propose that CI is feasible in patients with severe external and middle ear malformations. However, major malformations increase the risk of complications. As the facial nerve and cochlea are difficult to locate due to the lack of important anatomical landmarks, detailed planning and adequate preparation, including review of the preoperative imaging data, and the use of facial nerve monitoring and intraoperative imaging are very important. In addition, experienced surgeons should perform CI to ensure the success of the operation.
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Implante Coclear , Perda Auditiva Neurossensorial , Criança , Pré-Escolar , Cóclea/cirurgia , Implante Coclear/métodos , Feminino , Perda Auditiva Neurossensorial/diagnóstico por imagem , Perda Auditiva Neurossensorial/cirurgia , Humanos , Janela da Cóclea/cirurgia , Canais SemicircularesRESUMO
Fucosylation and its fucosidic linkage-specific motifs are believed to be essential to understand their distinct roles in cellular behavior, but their quantitative information has not yet been fully disclosed due to the requirements of ultra-sensitivity and selectivity. Herein, we report an approach that converts fucose (Fuc) to stable europium (Eu) isotopic mass signal on hard ionization inductively coupled plasma mass spectrometry (ICP-MS). Metabolically assembled azido-fucose on the cell surface allows us to tag them with an alkyne-customized Eu-crafted bacteriophage MS2 capsid nanoparticle for Eu signal multiplication, resulting in an ever lowest detection limit of 4.2 zmol Fuc. Quantitative breakdown of the linkage-specific fucosylation motifs in situ preserved on single cancerous HepG2 and paracancerous HL7702 cells can thus be realized on a single-cell ICP-MS platform, specifying their roles during the cancering process. This approach was further applied to the discrimination of normal hepatocellular cells and highly, moderately, and poorly differentiated hepatoma cells collected from real hepatocellular carcinoma tissues.
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ß-Site amyloid protein cleaving enzyme 1 (BACE1) is a promising therapeutic target for developing inhibitors to alleviate Alzheimer's disease (AD). Herein, we established an inductively coupled plasma mass spectrometry (ICPMS)-based inhibitor screening platform. A biotin-labeled lanthanide-coded peptide probe (LCPP; biotin-PEG2-EVNLDAEC-DOTA-Ln) was designed to determine the activity of BACE1 and evaluate the degree of inhibition of inhibitors. The platform was first validated with two commercially available inhibitors (BSI I and BSI IV) in terms of IC50 values and then applied to two newly designed inhibitors (inhibitors II and III) based on the crystal structure of BACE1 interacting with inhibitor I, and each of them contained an acylguanidine core structure. We found that their inhibition effects were improved as evaluated by the sensitive and accurate LCPP-ICPMS platform, demonstrating its ability for new drug screening.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide , Ácido Aspártico Endopeptidases , Inibidores Enzimáticos/farmacologia , Humanos , Espectrometria de MassasRESUMO
A sensing platform is presented for the determination of alkaline phosphatase (ALP) activity based on the cooperation of DNAzyme-Au spherical nucleic acid nanoprobe with the graphene-oxide-loaded hybridization chain reaction (HCR/GO) system to achieve good detection sensitivity and specificity. This assay takes advantage of the strong affinity of pyrophosphate (PPi) to Cu2+ ions and the fact that ALP can hydrolyze pyrophosphate (PPi) to release free Cu2+ ions. In the presence of ALP, the released Cu2+ can promote the Cu2+-dependent DNAzyme to cleave the substrate that generates a shorter DNA fragment, which is responsible for further triggering the HCR/GO system to form a long fluorescence dsDNA and thereby giving an amplified fluorescence signal. Linear calibration range was obtained from 0.2 to 10 U L-1, and the limit of detection (LOD) is about 0.14 U L-1. The feasibility of the proposed method was validated by spiking ALP standards in bovine serum. The recovery ranged from 97.2 to 104.6%, and a coefficient of variation (CV) of less than 8% (n = 3) was obtained. This assay strategy was also applied to evaluate the ALP inhibitor efficiency, which indicates that the assay has potential for drug screening.
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Fosfatase Alcalina/sangue , DNA Catalítico/química , Grafite/química , Nanopartículas Metálicas/química , Fosfatase Alcalina/química , Animais , Bovinos , Cobre/química , Difosfatos/química , Ouro/química , Humanos , Ácidos Nucleicos Imobilizados/química , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico/métodos , Espectrometria de Fluorescência/métodosRESUMO
We report an approach that polymerizable handle-modified nanosized metal organic frameworks (MOFs) are used as independent monomers to be covalently organized by crosslinking molecules (CLMs) into an orderly MOF-assembled hybrid monolithic stationary phase, overcoming the respective problems of previously reported MOF-mixed or embedded stationary phases so far. It has a hierarchical micro-, meso-, and macropore structure throughout the monolithic matrix that is donated from MOF themselves, formed via CLM crosslinking in-between MOFs and expended by porogenic solvents, and a tunable surface chemistry derived inherently from MOFs, regulated by CLMs and initiated by the mobile phases as well. Such a pore structure and surface chemistry display multiplex interactions of sieving and electrostatic repulsion in addition to the polarity-based interactions that synergistically govern the partitioning way and degree of target molecules between the stationary and mobile phases, thus offering the ability to simultaneously separate small and large molecules during one chromatographic run on a nano-flow capillary high-performance liquid chromatography platform. A baseline mutual separation with the HETP and Rs of, for example, 9.2 µm butylbenzene and 4.56 (butylbenzene and pentylbenzene), 7.9 µm (phenylalanine) and 3.50 (tryptophan and phenylalanine), and 7.0 µm (myoglobin) and 1.91 (bovine serum albumin and myoglobin) was achieved when UiO-66/NH-methacrylate was exemplified as a model of MOFs and 1,6-hexanediol dimethacrylate and stearyl methacrylate together as CLMs. Not limited to the MOFs and CLMs demonstrated here, other available MOFs and CLMs or newly designed and synthesized ones are expected to be used for constructing one's own desired monolithic stationary phases toward her/his particular purposes.
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A pathogenic bacterium has its own mechanisms for not only pathogenic attack but also exogenous invasion defense, in which the bacterial cell wall is the front line of attack and defense. We developed a biochemical lanthanide-encoding approach to quantify the uncanonical d-amino acid (d-X) that was edited in a small proportion into the terminal acyl-d-Ala-d-X of nascent peptidoglycan UDP-MurNAc-pentapeptides in the bacterial cell wall. This approach overcomes the difficulties regarding quantification and accuracy issues encountered by the popular optical imaging and traditional high-performance liquid chromatography-based methods. Newly synthesized azide-d-Leu and ketone-d-Met were used together with alkynyl-d-Ala for their metabolic assembly and then bioorthogonally encoded by the correspondingly fabricated DBCO-DOTA-Gd, H2NO-DOTA-Eu, and azide-DOTA-Sm tags. This approach allows direct quantification of the d-X in situ in the cell wall using 158Gd, 153Eu, and 154Sm species-unspecific isotope dilution inductively coupled plasma mass spectrometry, avoiding any tedious and complex "cell-broken" pretreatment procedures that might induce racemization of the d-X. The obtained site-specific and accurate in situ information about the d-X enables quantitative monitoring of the bacterial response when Staphylococcus aureus meets vancomycin, showing that the amounts of azide-d-Leu and ketone-d-Met assembled are more important after determining the structure- and composition-dependent bacterial antibiotic resistance mechanisms. In addition, we found that the combined use of vancomycin and d-Ala restores the efficacy of vancomycin and might be a wise and simple way to combat vancomycin intermediate-resistant S. aureus.