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1.
J Am Chem Soc ; 146(10): 6955-6961, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38422479

RESUMO

Machine learning is gaining momentum in the prediction and discovery of materials for specific applications. Given the abundance of metal-organic frameworks (MOFs), computational screening of the existing MOFs for propane/propylene (C3H8/C3H6) separation could be equally important for developing new MOFs. Herein, we report a machine learning-assisted strategy for screening C3H8-selective MOFs from the CoRE MOF database. Among the four algorithms applied in machine learning, the random forest (RF) algorithm displays the highest degree of accuracy. We experimentally verified the identified top-performing MOF (JNU-90) with its benchmark selectivity and separation performance of directly producing C3H6. Considering its excellent hydrolytic stability, JNU-90 shows great promise in the energy-efficient separation of C3H8/C3H6. This work may accelerate the development of MOFs for challenging separations.

2.
Angew Chem Int Ed Engl ; 63(27): e202403209, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647582

RESUMO

Metal-organic frameworks (MOFs) that exhibit dynamic phase-transition behavior under external stimuli could have great potential in adsorptive separations. Here we report on a zinc-based microporous MOF (JNU-80) and its reversible transformation between two crystalline phases: large pore (JNU-80-LP) and narrow pore (JNU-80-NP). Specifically, JNU-80-LP can undergo a dehydration-induced cluster consolidation under heat treatment, resulting in JNU-80-NP with a reduced channel that allows exclusion of di-branched hexane isomers while high adsorption of linear and mono-branched hexane isomers. We further demonstrate the fabrication of MOF-polymer composite (JNU-80-NP-block) and its application in the purification of di-branched isomers from liquid-phase hexane mixtures (98 % di-branched) at room temperature, affording the di-branched hexane isomers with 99.5 % purity and close to 90 % recovery rate over ten cycles. This work illustrates an interesting dehydration-induced cluster consolidation in MOF structure and the ensuing channel shrinkage for sieving di-branched hexane isomers, which may have important implications for the development of MOFs with dynamic behavior and their potential applications in non-thermal driven separation technologies.

3.
Small ; 19(43): e2303294, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37356060

RESUMO

The uncontrollable growth and uneven nucleation of lithium metal can be addressed by utilizing spatial confinement structures in conjunction with lithiophilic sites. However, their complex fabrication technique and the inhomogeneous dispersion of lithiophilic sites make the application ineffective. In this work, ultra-uniformly dispersed SiOx seeds and defects are produced in situ to achieve the spatially restricted protection within the reduced graphene oxide (rGO) layer. The in situ formed SiOx and defects during annealing double constrain lithium nucleation and growth behaviors thanks to the superlithiophilic characteristic, while both provide the fast Li+ transport channel to utilize the interlayer protection of rGO in limiting lithium dendrite growth. Furthermore, XANES and XPS analyze the SiOx seeds that are dominated by various valence states, and theoretical calculations further verify the control on the nucleation of lithium atoms. Benefiting from the optimum average valence of three for the "control site", the host realizes steady circulation. In asymmetric cells, the host demonstrates excellent coulombic efficiency of 99.1% and stable lifespans over 1250 h at 1 mA cm-2 . When assembled in LiFePO4 full cells, it retains a favorable capacity of 116.2 mA h g-1 after 170 cycles.

4.
Small ; 19(17): e2207167, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36703536

RESUMO

Because of its high specific capacity, the silicon-graphite composite (SGC) is regarded as a promising anode for new-generation lithium-ion batteries. However, the frequently employed two-section preparation process, including the modification of silicon seed and followed mixture with graphite, cannot ensure the uniform dispersion of silicon in the graphite matrix, resulting in a stress concentration of aggregated silicon domains and cracks in composite electrodes during cycling. Herein, inspired by powder engineering, the two independent sections are integrated to construct multistage stable silicon-graphite hybrid granules (SGHGs) through wet granulation and carbonization. This method assembles silicon nanoparticles (Si NPs) and graphite and improves compatibility between them, addressing the issue of severe stress concentration caused by uncombined residue of Si NPs. The optimal SGHG prepared with 20% pitch content exhibits a highly reversible specific capacity of 560.0 mAh g-1 at a current density of 200 mA g-1 and a considerable stability retention of 86.1% after 1000 cycles at 1 A g-1 . Moreover, as a practical application, the full cell delivers an outstanding capacity retention of 85.7% after 400 cycles at 2 C. The multistage stable structure constructed by simple wet granulation and carbonization provides theoretical guidance for the preparation of commercial SGC anodes.

5.
Phys Chem Chem Phys ; 25(16): 11717-11724, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37066517

RESUMO

Lattice water effects on the structures and magnetic properties of single-molecule magnets (SMMs) have attracted considerable attention. Herein, we have successfully synthesized two centrosymmetric binuclear compounds [Dy2(2,3'-ppcad)2(C2H3O2)4(H2O)2] (1) and [Dy2(2,3'-ppcad)2(C2H3O2)4(H2O)2]·6H2O (2) (2,3'-Hppcad = N3-(2-pyrazinyl)-3-pyridinecarboxamidrazone) by elaborately varying the amount of the base (LiOH·H2O). Through isothermal titration calorimetry (ITC), the interactions between DyIII ions and 2,3'-Hppcad with different amounts of LiOH·H2O were monitored in real time. Magnetic studies reveal that two compounds exhibit the typical zero-field single-molecule magnet behavior with different energy barrier (Ueff) values of 103.43 K for 1 and 386.48 K for 2, wherein the SMM performance for 2 stands out among the reported nine-coordinated Dy2-SMMs systems with spherical capped square antiprism (C4v) geometries. To rationalize the observed difference in the magnetic properties of 1 and 2, ab initio calculations have been performed. The introduction of lattice water molecules leads to differences in the J values observed for 1 and 2. The stronger antiferromagnetic DyIII-DyIII couplings in 2 were presented and the fast quantum tunneling of magnetization was further suppressed, thereby achieving a higher Ueff value. This work provides an effective strategy to enhance the SMM performance, and combines with ab initio calculations to explain how lattice water molecules can affect the magnetic interactions of Dy2-SMMs.

6.
Alzheimers Dement ; 19(1): 261-273, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35357079

RESUMO

HYPOTHESIS: We hypothesized that Lomecel-B, an allogeneic medicinal signaling cell (MSC) therapeutic candidate for Alzheimer's disease (AD), is safe and potentially disease-modifying via pleiotropic mechanisms of action. KEY PREDICTIONS: We prospectively tested the predictions that Lomecel-B administration to mild AD patients is safe (primary endpoint) and would provide multiple exploratory indications of potential efficacy in clinical and biomarker domains (prespecified secondary/exploratory endpoints). STRATEGY AND KEY RESULTS: Mild AD patient received a single infusion of low- or high-dose Lomecel-B, or placebo, in a double-blind, randomized, phase I trial. The primary safety endpoint was met. Fluid-based and imaging biomarkers indicated significant improvement in the Lomecel-B arms versus placebo. The low-dose Lomecel-B arm showed significant improvements versus placebo on neurocognitive and other assessments. INTERPRETATION: Our results support the safety of Lomecel-B for AD, suggest clinical potential, and provide mechanistic insights. This early-stage study provides important exploratory information for larger efficacy-powered clinical trials.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/tratamento farmacológico , Resultado do Tratamento , Método Duplo-Cego , Biomarcadores
7.
Int J Mol Sci ; 23(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36077599

RESUMO

Salmonella enterica, serovar Gallinarum, biovar Pullorum, is an avian-specific pathogen which has caused considerable economic losses to the poultry industry worldwide. Two-component systems (TCSs) play an essential role in obtaining nutrients, detecting the presence of neighboring bacteria and regulating the expression of virulence factors. The genome analysis of S. Pullorum strain S06004 suggesting the carriage of 22 pairs of TCSs, which belong to five families named CitB, OmpR, NarL, Chemotaxis and LuxR. In the CitB family, three pairs of TCSs, namely CitA-CitB, DcuS-DcuR and DpiB-DpiA, remain unaddressed in S. Pullorum. To systematically investigate the function of the CitB family in S. Pullorum, four mutants, ΔcitAB (abbreviated as Δcit), ΔdcuSR (Δdcu), ΔdpiBA (Δdpi) and ΔcitABΔdcuSRΔdpiBA (Δ3), were made using the CRISPR/Cas9 system. The results demonstrated that the CitB family did not affect the growth of bacteria, the results of biochemical tests, invasion and proliferation in chicken macrophage HD-11 cells and the expression of fimbrial protein. But the mutants showed thicker biofilm formation, higher resistance to antimicrobial agents, enhanced tolerance to inhibition by egg albumen and increased virulence in chicken embryos. Moreover, the deletion of Dpi TCS was detrimental to survival after exposure to hyperosmotic and oxidative environments, as well as the long-term colonization of the small intestine of chickens. Collectively, we provided new knowledge regarding the possible role of the CitB family involved in the pathogenic processes of S. Pullorum.


Assuntos
Doenças das Aves Domésticas , Salmonelose Animal , Salmonella enterica , Animais , Embrião de Galinha , Galinhas/microbiologia , Doenças das Aves Domésticas/microbiologia , Salmonella/genética , Salmonelose Animal/microbiologia
8.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(1): 99-102, 2022 Jan 30.
Artigo em Zh | MEDLINE | ID: mdl-35150118

RESUMO

OBJECTIVE: Improve the quality of testing in medical device manufacturers clean workshops to ensure the authenticity and reliability of testing data. METHODS: Analyze the problems and influencing factors found in the process of testing of medical device manufacturers clean workshops from 2016 to 2020, and put forward reasonable suggestions to ensure the quality of testing. RESULTS: In the process of testing, there are six factors that affect the quality of testing, including testing personnel, instruments and equipment, testing consumables, testing methods, testing environment and actual operation. CONCLUSIONS: To improve the quality of testing, should strengthen the training of testing personnel, continuously improve the testing quality management system, establish an effective information communication mechanism, find out the influencing factors in time, provide objective, real and effective testing data for medical device manufacturing enterprises, and provide technical support for the production and supervision of medical devices.


Assuntos
Comércio , Equipamentos e Provisões , Reprodutibilidade dos Testes
9.
J Proteome Res ; 20(6): 3134-3149, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34014671

RESUMO

Multiple myeloma is an incurable hematological malignancy that impacts tens of thousands of people every year in the United States. Treatment for eligible patients involves induction, consolidation with stem cell rescue, and maintenance. High-dose therapy with a DNA alkylating agent, melphalan, remains the primary drug for consolidation therapy in conjunction with autologous stem-cell transplantation; as such, melphalan resistance remains a relevant clinical challenge. Here, we describe a proteometabolomic approach to examine mechanisms of acquired melphalan resistance in two cell line models. Drug metabolism, steady-state metabolomics, activity-based protein profiling (ABPP, data available at PRIDE: PXD019725), acute-treatment metabolomics, and western blot analyses have allowed us to further elucidate metabolic processes associated with melphalan resistance. Proteometabolomic data indicate that drug-resistant cells have higher levels of pentose phosphate pathway metabolites. Purine, pyrimidine, and glutathione metabolisms were commonly altered, and cell-line-specific changes in metabolite levels were observed, which could be linked to the differences in steady-state metabolism of naïve cells. Inhibition of selected enzymes in purine synthesis and pentose phosphate pathways was evaluated to determine their potential to improve melphalan's efficacy. The clinical relevance of these proteometabolomic leads was confirmed by comparison of tumor cell transcriptomes from newly diagnosed MM patients and patients with relapsed disease after treatment with high-dose melphalan and autologous stem-cell transplantation. The observation of common and cell-line-specific changes in metabolite levels suggests that omic approaches will be needed to fully examine melphalan resistance in patient specimens and define personalized strategies to optimize the use of high-dose melphalan.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Humanos , Melfalan/farmacologia , Metabolômica , Mieloma Múltiplo/tratamento farmacológico , Transplante Autólogo
10.
Nano Lett ; 20(1): 372-383, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31840517

RESUMO

Angiogenesis is the hallmark of melanoma that nurtures the tumor microenvironment (TME) for rapid tumor progression. Vessel normalization could benefit melanoma treatment through TME reconstruction, while its limited duration and extent are still the drag. Herein, two kinds of look-like nanodrugs, called Gemini-like nanodrugs (GLnano), were constructed separately with the same scaffold of antiangiogenic low molecular weight heparin (LMWH) and mixed upon administration in vivo. For one, doxorubicin (DOX) was encapsulated into LMWH-chrysin nanodrug (LCY) with DSPE-PEG-anisamide decoration (D-LCA nanodrugs) for active targeting and direct cell killing toward melanoma cells. For another, matrix metalloproteinases (MMPs)-sensitive peptide was conjugated to LMWH to encapsulate celecoxib (Cel) (C-Lpep nanodrugs), disassembling in TME by MMPs and releasing Cel for M2-to-M1 reprogramming of tumor-associated macrophages. Our results showed that GLnano could remarkably elongate the vessel normalization window up to 12 days with the highest pericyte coverage of nearly 75%, compared to only 4 days by LCY monotherapy. Furthermore, GLnano could spontaneously form the "treatment-delivery" loop to promote nanodrugs toward deep tumor regions, leading to a potent tumor inhibition, metastasis prevention, and overall TME improvements.


Assuntos
Doxorrubicina , Sistemas de Liberação de Medicamentos , Heparina de Baixo Peso Molecular , Melanoma Experimental , Nanopartículas , Neovascularização Patológica , Microambiente Tumoral/efeitos dos fármacos , Animais , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Heparina de Baixo Peso Molecular/química , Heparina de Baixo Peso Molecular/farmacocinética , Heparina de Baixo Peso Molecular/farmacologia , Melanoma Experimental/sangue , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Nanopartículas/química , Nanopartículas/uso terapêutico , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Células RAW 264.7
11.
Genet Med ; 20(4): 470-473, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28837159

RESUMO

PurposeThe Genomic Oligoarray and SNP Array Evaluation Tool 3.0 matches candidate genes within regions of homozygosity with a patient's phenotype, by mining OMIM for gene entries that contain a Clinical Synopsis. However, the tool cannot identify genes/disorders whose OMIM entries lack a descriptor of the mode of (Mendelian) inheritance. This study aimed to improve the tool's diagnostic power by building a database of autosomal recessive diseases not diagnosable through OMIM.MethodsWe extracted a list of all genes in OMIM that produce disease phenotypes but lack Clinical Synopses or other statements of mode of inheritance. We then searched PubMed for literature regarding each gene in order to infer its inheritance pattern.ResultsWe analyzed 1,392 genes. Disorders associated with 372 genes were annotated as recessive and 430 as dominant. Autosomal genes were ranked from 1 to 3, with 3 indicating the strongest evidence behind the inferred mode of inheritance. Of 834 autosomal genes, 158 were ranked as 1, 228 as 2, and 448 as 3.ConclusionThe 372 genes associated with recessive disorders will be contributed to the SNP array tool, and the entire database to OMIM. We anticipate that these findings will be useful in rare disease diagnostics.


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Padrões de Herança , Genômica/métodos , Genótipo , Humanos , Anotação de Sequência Molecular , Fenótipo
12.
Mol Cancer ; 16(1): 85, 2017 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-28454577

RESUMO

BACKGROUND: The BRAF protein kinase is widely studied as a cancer driver and therapeutic target. However, the regulation of its expression is not completely understood. RESULTS: Taking advantage of the RNA-seq data of more than 4800 patients belonging to 9 different cancer types, we show that BRAF mRNA exists as a pool of 3 isoforms (reference BRAF, BRAF-X1, and BRAF-X2) that differ in the last part of their coding sequences, as well as in the length (BRAF-ref: 76 nt; BRAF-X1 and BRAF-X2: up to 7 kb) and in the sequence of their 3'UTRs. The expression levels of BRAF-ref and BRAF-X1/X2 are inversely correlated, while the most prevalent among the three isoforms varies from cancer type to cancer type. In melanoma cells, the X1 isoform is expressed at the highest level in both therapy-naïve cells and cells with acquired resistance to vemurafenib driven by BRAF gene amplification or expression of the Δ[3-10] splicing variant. In addition to the BRAF-ref protein, the BRAF-X1 protein (the full length as well as the Δ[3-10] variant) is also translated. The expression levels of the BRAF-ref and BRAF-X1 proteins are similar, and together they account for BRAF functional activities. In contrast, the endogenous BRAF-X2 protein is hard to detect because the C-terminal domain is selectively recognized by the ubiquitin-proteasome pathway and targeted for degradation. CONCLUSIONS: By shedding light on the repertoire of BRAF mRNA and protein variants, and on the complex regulation of their expression, our work paves the way to a deeper understanding of a crucially important player in human cancer and to a more informed development of new therapeutic strategies.


Assuntos
Melanoma/genética , Neoplasias/genética , Isoformas de Proteínas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Processamento Alternativo/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Éxons/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Indóis/administração & dosagem , Melanoma/tratamento farmacológico , Melanoma/patologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , RNA Mensageiro/genética , Sulfonamidas/administração & dosagem , Vemurafenib
14.
Appl Math Comput ; 256: 37-51, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25843986

RESUMO

Let [Formula: see text] be the open unit disk, [Formula: see text] an analytic self-map of [Formula: see text] and [Formula: see text] an analytic function on [Formula: see text]. Let D be the differentiation operator and [Formula: see text] the weighted composition operator. The boundedness and compactness of the product-type operator [Formula: see text] from the weighted Bergman-Orlicz space to the Bers type space, weighted Bloch space and weighted Zygmund space on [Formula: see text] are characterized.

15.
ACS Nano ; 18(18): 11941-11954, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38652811

RESUMO

Closed pores play a crucial role in improving the low-voltage (<0.1 V) plateau capacity of hard carbon anodes for sodium-ion batteries (SIBs). However, the lack of simple and effective closed-pore construction strategies, as well as the unclear closed-pore formation mechanism, has severely hindered the development of high plateau capacity hard carbon anodes. Herein, we present an effective closed-pore construction strategy by one-step pyrolysis of zinc gluconate (ZG) and elucidate the corresponding mechanism of closed-pore formation. The closed-pore formation mechanism during the pyrolysis of ZG mainly involves (i) the precipitation of ZnO nanoparticles and the ZnO etching on carbon under 1100 °C to generate open pores of 0.45-4 nm and (ii) the development of graphitic domains and the shrinkage of the partial open pores at 1100-1500 °C to convert the open pores to closed pores. Benefiting from the considerable closed-pore content and suitable microstructure, the optimized hard carbon achieves an ultrahigh reversible specific capacity of 481.5 mA h g-1 and an extraordinary plateau capacity of 389 mA h g-1 for use as the anode of SIBs. Additionally, some in situ and ex situ characterizations demonstrate that the high-voltage slope capacity and the low-voltage plateau capacity stem from the adsorption of Na+ at the defect sites and Na-cluster formation in closed pores, respectively.

16.
Elife ; 132024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38959062

RESUMO

Bacterial exonuclease III (ExoIII), widely acknowledged for specifically targeting double-stranded DNA (dsDNA), has been documented as a DNA repair-associated nuclease with apurinic/apyrimidinic (AP)-endonuclease and 3'→5' exonuclease activities. Due to these enzymatic properties, ExoIII has been broadly applied in molecular biosensors. Here, we demonstrate that ExoIII (Escherichia coli) possesses highly active enzymatic activities on ssDNA. By using a range of ssDNA fluorescence-quenching reporters and fluorophore-labeled probes coupled with mass spectrometry analysis, we found ExoIII cleaved the ssDNA at 5'-bond of phosphodiester from 3' to 5' end by both exonuclease and endonuclease activities. Additional point mutation analysis identified the critical residues for the ssDNase action of ExoIII and suggested the activity shared the same active center with the dsDNA-targeted activities of ExoIII. Notably, ExoIII could also digest the dsDNA structures containing 3'-end ssDNA. Considering most ExoIII-assisted molecular biosensors require the involvement of single-stranded DNA (ssDNA) or nucleic acid aptamer containing ssDNA, the activity will lead to low efficiency or false positive outcome. Our study revealed the multi-enzymatic activity and the underlying molecular mechanism of ExoIII on ssDNA, illuminating novel insights for understanding its biological roles in DNA repair and the rational design of ExoIII-ssDNA involved diagnostics.


Assuntos
DNA de Cadeia Simples , Escherichia coli , Exodesoxirribonucleases , Exodesoxirribonucleases/metabolismo , Exodesoxirribonucleases/genética , DNA de Cadeia Simples/metabolismo , DNA de Cadeia Simples/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/enzimologia , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética
17.
Sci Data ; 11(1): 244, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413596

RESUMO

Infectious disease outbreaks transcend the medical and public health realms, triggering widespread panic and impeding socio-economic development. Considering that self-limiting diarrhoea of sporadic cases is usually underreported, the Salmonella outbreak (SO) study offers a unique opportunity for source tracing, spatiotemporal correlation, and outbreak prediction. To summarize the pattern of SO and estimate observational epidemiological indicators, 1,134 qualitative reports screened from 1949 to 2023 were included in the systematic review dataset, which contained a 506-study meta-analysis dataset. In addition to the dataset comprising over 50 columns with a total of 46,494 entries eligible for inclusion in systematic reviews or input into prediction models, we also provide initial literature collection datasets and datasets containing socio-economic and climate information for relevant regions. This study has a broad impact on advancing knowledge regarding epidemic trends and prevention priorities in diverse salmonellosis outbreaks and guiding rational policy-making or predictive modeling to mitigate the infringement upon the right to life imposed by significant epidemics.


Assuntos
Surtos de Doenças , Intoxicação Alimentar por Salmonella , Infecções por Salmonella , Humanos , China/epidemiologia , Coleta de Dados , Salmonella , Intoxicação Alimentar por Salmonella/epidemiologia , Infecções por Salmonella/epidemiologia , Revisões Sistemáticas como Assunto , Metanálise como Assunto
18.
BMC Genomics ; 14: 917, 2013 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-24365332

RESUMO

BACKGROUND: Myzus persicae, the green peach aphid, is a polyphagous herbivore that feeds from hundreds of species of mostly dicot crop plants. Like other phloem-feeding aphids, M. persicae rely on the endosymbiotic bacterium, Buchnera aphidicola (Buchnera Mp), for biosynthesis of essential amino acids and other nutrients that are not sufficiently abundant in their phloem sap diet. Tobacco-specialized M. persicae are typically red and somewhat distinct from other lineages of this species. To determine whether the endosymbiotic bacteria of M. persicae could play a role in tobacco adaptation, we sequenced the Buchnera Mp genomes from two tobacco-adapted and two non-tobacco M. persicae lineages. RESULTS: With a genome size of 643.5 kb and 579 predicted genes, Buchnera Mp is the largest Buchnera genome sequenced to date. No differences in gene content were found between the four sequenced Buchnera Mp strains. Compared to Buchnera APS from the well-studied pea aphid, Acyrthosiphon pisum, Buchnera Mp has 21 additional genes. These include genes encoding five enzymes required for biosynthesis of the modified nucleoside queosine, the heme pathway enzyme uroporphyrinogen III synthase, and asparaginase. Asparaginase, which is also encoded by the genome of the aphid host, may allow Buchnera Mp to synthesize essential amino acids from asparagine, a relatively abundant phloem amino acid. CONCLUSIONS: Together our results indicate that the obligate intracellular symbiont Buchnera aphidicola does not contribute to the adaptation of Myzus persicae to feeding on tobacco.


Assuntos
Afídeos/microbiologia , Buchnera/genética , Genoma Bacteriano , Simbiose , Adaptação Biológica , Animais , Buchnera/classificação , Mapeamento Cromossômico , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Repetições de Microssatélites , Plasmídeos/genética , Análise de Sequência de DNA , Nicotiana
19.
Genet Med ; 15(5): 354-60, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23100014

RESUMO

PURPOSE: This report describes a fast online tool to accelerate and improve clinical interpretation of single nucleotide polymorphism array results for diagnostic purposes, when consanguinity or inbreeding is identified. METHODS: We developed a web-based program that permits entry of regions of homozygosity and, using OMIM, UCSC, and NCBI databases, retrieves genes within these regions as well as their associated autosomal recessive disorders. Relevant OMIM Clinical Synopses can be searched, using key clinical terms permitting further filtering for candidate genes and disorders. RESULTS: The tool aids the clinician by arriving at a short list of relevant candidate disorders, guiding the continued diagnostic work-up. Its efficacy is illustrated by presenting seven patients who were diagnosed using this tool. CONCLUSION: The online single nucleotide polymorphism array evaluation tool rapidly and systematically identifies relevant genes and associated conditions mapping to identified regions of homozygosity. The built-in OMIM clinical feature search allows the user to further filter to reach a short list of candidate conditions relevant for the diagnosis, making it possible to strategize more focused diagnostic testing. The tabulated results can be downloaded and saved to the desktop in an Excel format. Its efficacy is illustrated by providing a few clinical examples.Genet Med 2013:15(5):354-360.


Assuntos
Consanguinidade , Genes Recessivos , Serviços em Genética , Polimorfismo de Nucleotídeo Único , Software , Algoritmos , Criança , Pré-Escolar , Bases de Dados de Ácidos Nucleicos , Feminino , Homozigoto , Humanos , Lactente , Recém-Nascido , Internet , Masculino , Informática Médica/métodos
20.
ACS Appl Mater Interfaces ; 15(36): 43048-43059, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37647234

RESUMO

High performance has always been the research focus of elastomers. However, there are inherent conflicts among properties of elastomers, such as strength and toughness, strength and damping performance, strength and self-healing ability, etc. Herein, first, we synthesized a unique structure of the dangling chain containing proton donors and receptors. Then, we design and fabricate a kind of high-performance elastomer with a gradient distribution of a dangling chain and a dynamic bond structure. The dangling chains of different lengths intertwine with each other and self-assemble to form a "dense accumulation" structure driven by hydrogen bonds, and the elastomer exhibits special micro/nano scale aggregated states and microphase separation. The "dense accumulation" structure plays a vital role in the increase of mechanical properties. Meanwhile, under the joint action of a dangling chain and a dynamic bond, the damping performance and self-healing performance of the elastomer are greatly enhanced. High strength (27.5 MPa), toughness (121.9 MJ·m-3), 94.8% healing efficiency and outstanding damping performance (tan δ ≥ 0.4, high damping temperature range up to 144 °C) are simultaneously achieved beyond the current state-of-the-art. This topoarchitected polymer with a gradient distribution of dangling chains successfully solves the defects of conventional branched polymers in deteriorating their mechanical properties. This material design provides a new strategy for the development of high-performance structural and functional integrated elastomers.

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