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1.
Cell Host Microbe ; 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34492225

RESUMO

The pore-forming protein gasdermin D (GSDMD) executes lytic cell death called pyroptosis to eliminate the replicative niche of intracellular pathogens. Evolution favors pathogens that circumvent this host defense mechanism. Here, we show that the Shigella ubiquitin ligase IpaH7.8 functions as an inhibitor of GSDMD. Shigella is an enteroinvasive bacterium that causes hemorrhagic gastroenteritis in primates, but not rodents. IpaH7.8 contributes to species specificity by ubiquitinating human, but not mouse, GSDMD and targeting it for proteasomal degradation. Accordingly, infection of human epithelial cells with IpaH7.8-deficient Shigella flexneri results in increased GSDMD-dependent cell death compared with wild type. Consistent with pyroptosis contributing to murine disease resistance, eliminating GSDMD from NLRC4-deficient mice, which are already sensitized to oral infection with Shigella flexneri, leads to further enhanced bacterial replication and increased disease severity. This work highlights a species-specific pathogen arms race focused on maintenance of host cell viability.

2.
J Med Microbiol ; 70(8)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34397349

RESUMO

Introduction. Lactococcus petauri LZys1 (L. petauri LZys1) is a type of lactic acid bacteria (LAB), which was initially isolated from healthy human gut.Hypothesis/Gap Statement. It was previously anticipated that L. petauri LZys1 has potential characteristics of probiotic properties. The genetic structure and the regulation functions of L. petauri LZys1 need to be better revealed.Aim. The aim of this study was to detect the probiotic properties L. petauri LZys1 and to reveal the genome information related to its genetic adaptation and probiotic profiles.Methodology. Multiple in vitro experiments were carried out to evaluate its lactic acid-producing ability, resistance to pathogenic bacterial strains, auto-aggregation and co-aggregation ability, and so on. Additionally, complete genome sequencing, gene annotation, and probiotic associated gene analysis were performed.Results. The complete genome of L. petauri LZys1 comprised of 1 985 765 bp, with a DNA G+C content of 38.07 %, containing 50 tRNA, seven rRNA, and four sRNA. A total of 1931 genes were classified into six functional categories by Kyoto Encyclopaedia of Genes and Genomes (KEGG) database. The neighbour-joining phylogeny tree based on the whole genome of L. petauri LZys1 and other probiotics demonstrated that L. petauri LZys1 has a significant similarity to Lactococcus garvieae. The functional genes were detected to expound the molecular mechanism and biochemical processes of its potential probiotic properties, such as atpB gene.Conclusion. All the results described in this study, together with relevant information previously reported, made L. prtauri LZys1 a very interesting potential strain to be considered as a prominent candidate for probiotic use.


Assuntos
Trato Gastrointestinal/microbiologia , Genoma Bacteriano , Lactococcus , Probióticos , Animais , Bactérias/crescimento & desenvolvimento , Bactérias/patogenicidade , Sequência de Bases , Fezes/microbiologia , Genes Bacterianos , Humanos , Lactococcus/citologia , Lactococcus/genética , Lactococcus/isolamento & purificação , Lactococcus/fisiologia , Masculino , Anotação de Sequência Molecular , Mariposas/microbiologia , Filogenia , Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/genética , Sequenciamento Completo do Genoma , Adulto Jovem
3.
Nature ; 596(7870): 97-102, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34290404

RESUMO

Infection-induced aversion against enteropathogens is a conserved sickness behaviour that can promote host survival1,2. The aetiology of this behaviour remains poorly understood, but studies in Drosophila have linked olfactory and gustatory perception to avoidance behaviours against toxic microorganisms3-5. Whether and how enteric infections directly influence sensory perception to induce or modulate such behaviours remains unknown. Here we show that enteropathogen infection in Drosophila can modulate olfaction through metabolic reprogramming of ensheathing glia of the antennal lobe. Infection-induced unpaired cytokine expression in the intestine activates JAK-STAT signalling in ensheathing glia, inducing the expression of glial monocarboxylate transporters and the apolipoprotein glial lazarillo (GLaz), and affecting metabolic coupling of glia and neurons at the antennal lobe. This modulates olfactory discrimination, promotes the avoidance of bacteria-laced food and increases fly survival. Although transient in young flies, gut-induced metabolic reprogramming of ensheathing glia becomes constitutive in old flies owing to age-related intestinal inflammation, which contributes to an age-related decline in olfactory discrimination. Our findings identify adaptive glial metabolic reprogramming by gut-derived cytokines as a mechanism that causes lasting changes in a sensory system in ageing flies.


Assuntos
Envelhecimento/metabolismo , Citocinas/metabolismo , Drosophila melanogaster/metabolismo , Intestinos , Neuroglia/metabolismo , Olfato/fisiologia , Animais , Aprendizagem da Esquiva , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/microbiologia , Feminino , Inflamação/metabolismo , Inflamação/microbiologia , Intestinos/microbiologia , Janus Quinases/metabolismo , Ácido Láctico/metabolismo , Metabolismo dos Lipídeos , Neurônios/metabolismo , Pectobacterium carotovorum , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Taxa de Sobrevida , Fatores de Transcrição/metabolismo
4.
Psychol Rep ; : 332941211013531, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34034570

RESUMO

The 10-item Connor-Davidson Resilience Scale (CD-RISC-10) is a self-report instrument widely used to assess resilience in particular demographics. This study aimed to evaluate the validity and measurement invariance (MI) of the CD-RISC-10 in Chinese left-behind children. A total of 968 children from three middle schools in Guizhou Province participated in this study, with the CD-RISC-10 used twice, at the base line time point and again after six months. The Ego-resilience Scale (ERS), and General Self-efficiency Scale (GSES-10) were also used as criteria-related validity instruments. Confirmatory factor analysis (CFA) was carried out to examine the one-factor model and the MI with regards to gender and left-behind status, as well as the longitudinal measurement invariance (LMI). The study proved satisfactory reliability and validity of the CD-RISC-10, with good criterion validity with the ERS and GSES-10. CFA results showed that the satisfactory model fit for the one-factor structure was supported in all groups (e.g., CFI = .942, TLI = .925, RMSEA = .057). The strict MI was evident across genders, as well as both the left-behind and non-left-behind groups. Additionally, the LMI of the CD-RISC-10 was also adequately supported. Generally speaking, these findings demonstrate that the CD-RISC-10 can effectively measure the resilience level of left-behind children - boys as well as girls - in China.

5.
Proc Natl Acad Sci U S A ; 118(1)2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33443214

RESUMO

Tandem gene amplification is a frequent and dynamic source of antibiotic resistance in bacteria. Ongoing expansions and contractions of repeat arrays during population growth are expected to manifest as cell-to-cell differences in copy number (CN). As a result, a clonal bacterial culture could comprise subpopulations of cells with different levels of antibiotic sensitivity that result from variable gene dosage. Despite the high potential for misclassification of heterogenous cell populations as either antibiotic-susceptible or fully resistant in clinical settings, and the concomitant risk of inappropriate treatment, CN distribution among cells has defied analysis. Here, we use the MinION single-molecule nanopore sequencer to uncover CN heterogeneity in clonal populations of Escherichia coli and Acinetobacter baumannii grown from single cells isolated while selecting for resistance to an optimized arylomycin, a member of a recently discovered class of Gram-negative antibiotic. We found that gene amplification of the arylomycin target, bacterial type I signal peptidase LepB, is a mechanism of unstable arylomycin resistance and demonstrate in E. coli that amplification instability is independent of RecA. This instability drives the emergence of a nonuniform distribution of lepB CN among cells with a range of 1 to at least 50 copies of lepB identified in a single clonal population. In sum, this remarkable heterogeneity, and the evolutionary plasticity it fuels, illustrates how gene amplification can enable bacterial populations to respond rapidly to novel antibiotics. This study establishes a rationale for further nanopore-sequencing studies of heterogeneous cell populations to uncover CN variability at single-molecule resolution.


Assuntos
Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Escherichia coli/genética , Amplificação de Genes/efeitos dos fármacos , Proteínas de Membrana/genética , Sequenciamento por Nanoporos/métodos , Peptídeos Cíclicos/genética , Serina Endopeptidases/genética , Variações do Número de Cópias de DNA , Proteínas de Ligação a DNA/metabolismo , Proteínas de Escherichia coli/metabolismo , Heterogeneidade Genética , Sequenciamento de Nucleotídeos em Larga Escala , Testes de Sensibilidade Microbiana , Mutação , Sequenciamento por Nanoporos/instrumentação , Recombinases Rec A/metabolismo
6.
Phys Chem Chem Phys ; 22(44): 25904-25917, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33164003

RESUMO

Ag-Cu-Au ternary alloys are promising solder materials for wire bonding. Limited experimental studies on Ag-Cu-Au materials can be found due to the high cost of gold. In this study, face-centered-cubic Cu(100), Cu(111), and Cu(110) substrates wetted by molten Ag45Cu42Au13 were investigated via molecular dynamics (MD). As demonstrated by melting simulation results, the Ag45Cu42Au13 alloy has a lower melting temperature compared to the eutectic alloy, Ag60Cu40. MD methods were also used to investigate the dissolutive characteristics of Ag45Cu42Au13/Cu wetting. Density profiles and contact angles show an increase in wettability in the Ag45Cu42Au13/Cu(100) wetting system. For molten Ag60Cu40 and Ag45Cu42Au13 the spreading behavior on Cu(100) shows a promoted tendency, which contrasts with both Cu(111) and Cu(110). Solid-liquid adhesion is indicative of the comparative spreading degrees. The contact angles and PMF analysis of wetting behaviors on rough and smooth Cu substrates illustrate that solid-liquid adhesion in Wenzel states is stronger than in Cassie wetting states.

7.
Int J Biol Macromol ; 150: 823-830, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32068058

RESUMO

The interaction behavior between food bio-macromolecules is the key point to develop the novel functional food ingredients. Effects of high pressure (HP) or microwave treatment (MW) on the physicochemical properties and microstructures of soy protein hydrolysates (SH)/ß-glucan/ferulic acid complexes (S-G-F) were investigated. The results showed that both HP and MW treatment significantly reduced the S-G-F complex particle size and fluorescence intensity along with the improved thermal stability and antioxidant activity but did not affect the zeta potential and the crystal structure. HP treatment changed the conformation of SH by increasing the ß-sheet content and decreasing the unordered structure, while MW treatment induce the increase in random coils content and the decreased in the α-helix content of SH. Accordingly, compared with MW treatment, HP treatment could result in the formation of a more compact structure with the uniform distribution through the stronger hydrogen bonding and hydrophobic interaction between components. This work revealed the interaction behaviors of food multi-component self-assembled nanoscale aggregation under high-technology in the food processing, which could provide a new direction for the development of antioxidant food ingredients by effectively utilizing the interaction between food components.


Assuntos
Ácidos Cumáricos/química , Manipulação de Alimentos/métodos , Tecnologia de Alimentos/métodos , Micro-Ondas , Hidrolisados de Proteína/química , Proteínas de Soja/química , beta-Glucanas/química , Antioxidantes , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Pressão , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Difração de Raios X
8.
Cancer Discov ; 10(2): 232-253, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31699795

RESUMO

With only a fraction of patients responding to cancer immunotherapy, a better understanding of the entire tumor microenvironment is needed. Using single-cell transcriptomics, we chart the fibroblastic landscape during pancreatic ductal adenocarcinoma (PDAC) progression in animal models. We identify a population of carcinoma-associated fibroblasts (CAF) that are programmed by TGFß and express the leucine-rich repeat containing 15 (LRRC15) protein. These LRRC15+ CAFs surround tumor islets and are absent from normal pancreatic tissue. The presence of LRRC15+ CAFs in human patients was confirmed in >80,000 single cells from 22 patients with PDAC as well as by using IHC on samples from 70 patients. Furthermore, immunotherapy clinical trials comprising more than 600 patients across six cancer types revealed elevated levels of the LRRC15+ CAF signature correlated with poor response to anti-PD-L1 therapy. This work has important implications for targeting nonimmune elements of the tumor microenvironment to boost responses of patients with cancer to immune checkpoint blockade therapy. SIGNIFICANCE: This study describes the single-cell landscape of CAFs in pancreatic cancer during in vivo tumor evolution. A TGFß-driven, LRRC15+ CAF lineage is associated with poor outcome in immunotherapy trial data comprising multiple solid-tumor entities and represents a target for combinatorial therapy.This article is highlighted in the In This Issue feature, p. 161.


Assuntos
Fibroblastos Associados a Câncer/imunologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Inibidores de Checkpoint Imunológico/farmacologia , Proteínas de Membrana/metabolismo , Miofibroblastos/imunologia , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/imunologia , Linhagem Celular Tumoral , Linhagem da Célula/genética , Linhagem da Célula/imunologia , Ensaios Clínicos como Assunto , Biologia Computacional , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/imunologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/imunologia , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Camundongos , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/imunologia , RNA-Seq , Análise de Célula Única , Fator de Crescimento Transformador beta/metabolismo , Resultado do Tratamento , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
9.
Microb Pathog ; 137: 103741, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31513894

RESUMO

The aim of this study was to estimate the therapeutic potential of specific egg yolk immunoglobulin (IgY) on dermatophytosis caused by Trichophyton rubrum. The IgY was produced by immunizing hens with cell wall proteins of T. rubrum, extracted from eggs by PEG precipitation and then purified by ammonium sulfate precipitation. The cross-reactivity (CR) with other fungi, growth inhibition on T. rubrum in vitro and therapeutic effect on T. rubrum infection in BALB/C mice of the specific IgY were then evaluated. Anti- T. rubrum cell wall proteins IgY (anti-trCWP IgY) presented a certain degree of cross-reactivity with different fungi. In the in vitro and in vivo activity researches, Anti-trCWP IgY showed a significant dose-dependent growth inhibitory effect on T. rubrum in vitro and a significant dose-dependent therapeutic effect on T. rubrum infection in BALB/C mice.


Assuntos
Anticorpos Antifúngicos/farmacologia , Gema de Ovo/imunologia , Imunoglobulinas/farmacologia , Proteínas de Membrana/imunologia , Tinha/tratamento farmacológico , Trichophyton/efeitos dos fármacos , Animais , Antígenos de Fungos/imunologia , Galinhas , Estudos Transversais , Modelos Animais de Doenças , Imunização , Imunoglobulinas/imunologia , Imunoglobulinas/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Pele/patologia , Tinha/patologia , Trichophyton/imunologia
10.
J Microencapsul ; 36(7): 622-634, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31478411

RESUMO

Aim: To design novel emulsifiers with the ability to improve the storage and digestion stability of curcumin emulsions, besides to investigate the influence of phenolic acids types on the emulsify ability of soy protein-pectin-phenolic acids complexes obtained by ultrasonication. Methods: The ternary complexes were characterised by particle size, morphology, zeta potential, X-ray diffraction, Fourier transform infra-red and fluorescence spectroscopy. Additionally, changes in droplet size, charge, and microstructure were monitored as quantitative stability index of curcumin emulsions. Results: Phenolic acid types significantly affected the formation of ternary complexes. Soy protein-pectin-ferulic acid complex (S-P-F) stabilised curcumin emulsion had the best emulsifying property, followed by soy protein-pectin- ellagic acid (S-P-E), and soy protein-pectin-tannic acid complexes (S-P-T). Moreover, S-P-F emulsion was found to retain efficiently cucumin within 30 days storage (77.35%) and simulated gastrointestinal tract (64.09%). Conclusion: Protein-polysaccharide-phenolic acids emulsions are effective oral delivery systems for hydrophobic bioactives.


Assuntos
Antineoplásicos/administração & dosagem , Curcumina/administração & dosagem , Emulsões/química , Hidroxibenzoatos/química , Pectinas/química , Proteínas de Soja/química , Antineoplásicos/química , Curcumina/química , Digestão , Portadores de Fármacos/química , Estabilidade de Medicamentos , Emulsificantes/química , Humanos
11.
Cancer Res ; 79(19): 4828-4839, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31416841

RESUMO

Mutations in KEAP1 and NFE2L2 (encoding the protein Nrf2) are prevalent in both adeno and squamous subtypes of non-small cell lung cancer, as well as additional tumor indications. The consequence of these mutations is stabilized Nrf2 and chronic induction of a battery of Nrf2 target genes. We show that knockdown of Nrf2 caused modest growth inhibition of cells growing in two-dimension, which was more pronounced in cell lines expressing mutant KEAP1. In contrast, Nrf2 knockdown caused almost complete regression of established KEAP1-mutant tumors in mice, with little effect on wild-type (WT) KEAP1 tumors. The strong dependency on Nrf2 could be recapitulated in certain anchorage-independent growth environments and was not prevented by excess extracellular glutathione. A CRISPR screen was used to investigate the mechanism(s) underlying this dependence. We identified alternative pathways critical for Nrf2-dependent growth in KEAP1-mutant cell lines, including the redox proteins thioredoxin and peroxiredoxin, as well as the growth factor receptors IGF1R and ERBB3. IGF1R inhibition was effective in KEAP1-mutant cells compared with WT, especially under conditions of anchorage-independent growth. These results point to addiction of KEAP1-mutant tumor cells to Nrf2 and suggest that inhibition of Nrf2 or discrete druggable Nrf2 target genes such as IGF1R could be an effective therapeutic strategy for disabling these tumors. SIGNIFICANCE: This study identifies pathways activated by Nrf2 that are important for the proliferation and tumorigenicity of KEAP1-mutant non-small cell lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Transdução de Sinais/fisiologia , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Xenoenxertos , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Neoplasias Pulmonares/genética , Camundongos , Mutação , Fator 2 Relacionado a NF-E2/metabolismo , Receptor ErbB-3/metabolismo , Receptor IGF Tipo 1/metabolismo
12.
J Microencapsul ; 36(4): 385-398, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31238757

RESUMO

Purpose: To evaluate the feasibility of soy protein hydrolysates (SPH)-tannic acid (TA) complex nanoparticle obtained by photocatalysis (SPH-T (P)) to construct curcumin (Cur) delivery vehicles. Methods: The interaction behaviour of SPH-T (P) was investigated using Fourier transform infra-red, X-ray diffraction and differential scanning calorimeter analyzes. Formation and stability of the complexes were characterised by particle size, morphology, zeta potential, and in vitro release. Results: Negatively charged Cur-loaded complex with small size (<100 nm), spherical cluster shape and uniform size distribution were formed through the driving force of electrostatic attraction, followed by hydrogen bonding. The presence of photocatalysis in the complexes significantly improved the storage stability and in vitro sustained release of curcumin by enhancing the hydrogen bonding, hydrophobic effects and π-π stacking interactions between SPH and TA. Conclusion: SPH-T (P) would be a useful and promising delivery vehicle for encapsulating, protecting, and delivering hydrophobic nutraceuticals.


Assuntos
Antineoplásicos/administração & dosagem , Curcumina/administração & dosagem , Portadores de Fármacos/química , Proteínas de Soja/química , Taninos/química , Antineoplásicos/química , Catálise , Curcumina/química , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Hidrólise , Tamanho da Partícula
13.
Nanoscale ; 11(22): 10927-10931, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31139811

RESUMO

Due to the elusive nature of polyoxometallates (POMs) in the assembly of silver clusters, POMs trapped by silver clusters are usually different from the pristine form, which surely increases the novelty of the assembly results but makes the final structure predictability challenging. Herein, three novel high-nuclearity silver-thiolate clusters trapping two kinds of classical POMs, Lindqvist-Mo6O192- and V10O286-, are reported. They are identified to be [(V10O28)@Ag44] (SD/Ag44a), [(V10O28)@Ag46] (SD/Ag46), and [(Mo6O19)@Ag44] (SD/Ag44b) clusters, which are further extended to 1D chain, 2D sql layer, and 3D pcu framework, respectively. Of note, SD/Ag44b contains a regular cubic Mo6O19 core sealed by an Ag44(EtS)24 shell in a pseudo-sodalite unit and six SCl4 planar squares connecting the respective adjacent silver tetragonal faces. This structure is a novel zeolite closely related to the natural alumino-silicate 'sodalite' but exceptionally made of core-shell silver clusters. Moreover, the Oh symmetric Mo6O192- templates an Oh symmetric Ag44 cluster in SD/Ag44b, realizing authentic symmetry delivery from guest to host in this system. This is a rare silver cluster family with classical POMs encapsulated.

14.
Polymers (Basel) ; 11(3)2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30960537

RESUMO

Polymer materials exhibit unique properties in the fabrication of optical waveguide devices, electromagnetic devices, and bio-devices. Direct laser writing (DLW) technology is widely used for micro-structure fabrication due to its high processing precision, low cost, and no need for mask exposure. This paper reviews the latest research progresses of polymer-based micro/nano-devices fabricated using the DLW technique as well as their applications. In order to realize various device structures and functions, different manufacture parameters of DLW systems are adopted, which are also investigated in this work. The flexible use of the DLW process in various polymer-based microstructures, including optical, electronic, magnetic, and biomedical devices are reviewed together with their applications. In addition, polymer materials which are developed with unique properties for the use of DLW technology are also discussed.

15.
Sensors (Basel) ; 19(1)2019 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-30621353

RESUMO

Polymer-based single-microring biosensors usually have a small free spectral range (FSR) that hampers the tracing of the spectrum shifting in the measurement. A cascade of two microring resonators based on the Vernier effect, is applied in this article in order to make up for this defect. A small FSR difference between the reference microring and the sensing microring is designed, in order to superpose the periodic envelope signal onto the constituent peaks, which makes it possible to continuously track the spectrum of the sensor. The optical polymer material, Ormocore, which has a large transparent window, is used in the fabrication. The biosensor is fabricated by using an UV-based soft imprint technique, which is considered to be cost-effective and suitable for mass production. By optimizing the volume ratio of Ormocore and the maT thinner, the device can be fabricated almost without a residual layer. The device works at a wavelength of 840 nm, where water absorption loss is much lower than at the infrared wavelengths. A two-step fitting method, including single-peak fitting and whole-envelope fitting, is applied in order to trace the spectral shift accurately. Finally, the two-cascaded-microrings biosensor is characterized, and the obtained FSR is 4.6 nm, which is 16 times larger than the FSR of the single microring biosensor demonstrated in our previous work. Moreover, the sensitivity can also be amplified by 16-fold, thanks to the Vernier effect.


Assuntos
Técnicas Biossensoriais , Polímeros/química , Refratometria , Água/química , Luz , Polímeros/síntese química , Transdutores
16.
J Pharm Biomed Anal ; 162: 179-184, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30261444

RESUMO

C-peptide level is recognized as an important indicator of diabetes diagnosis. A sensitive and specific double-antibody sandwich enzyme-linked immunosorbent assay for the detection of C-peptide based on double antibody sandwich method was studied in this paper. The rabbit and hen were innunized with PLL-C-peptide and BSA-C-peptide respectively to obtain specific Yolk antibody (IgY) and polyclonal antibody used to construct the sandwich ELISA for the measurement of C-peptide. The limit of detection was 0.51 µg/mL and the half maximal inhibitory concentration (IC50) was 3.26 µg/mL. The method developed in the study showed no evident cross-reactivity with other similar analogs. The detection standard curve of C-peptide exhibited a good linearity (R2 = 0.9896, n = 15). 17 types of the urine of diabetes patients on c-peptide levels compared with the hospital type of diabetes information, with a conclusion of a high consistent rate. Therefore, the methods could be selectively used for rapid screening of C-peptide in human urine, and the type of diabetes has some referential significance.


Assuntos
Anticorpos/imunologia , Peptídeo C/urina , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Adulto , Idoso , Especificidade de Anticorpos , Biomarcadores/urina , Peptídeo C/imunologia , Diabetes Mellitus Tipo 1/urina , Diabetes Mellitus Tipo 2/urina , Diagnóstico Diferencial , Feminino , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Fatores de Tempo , Urinálise , Fluxo de Trabalho , Adulto Jovem
17.
J Agric Food Chem ; 66(30): 8094-8103, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29976058

RESUMO

Nowadays, natural antioxidants abundant in polyphenols have been widely used to substitute synthetic antioxidants in meat products. In general, high doses of natural antioxidants are required to provide comparative antioxidant effects as synthetic antioxidants. Noticeably, the qualities of meat products can be jeopardized due to interactions between polyphenols and myofibrillar proteins (MPs). In this study, methyl-ß-cyclodextrin was used to increase the polyphenol loading amount by preventing interactions between polyphenols and proteins. Solubility, electrophoresis, fluorescence spectroscopy, and surface hydrophobicity analyses indicated that methyl-ß-cyclodextrin could dose-dependently inhibit epigallocatechin-3-gallate-induced attacks on MPs under oxidative stress. Gel strength, cooking loss, confocal laser scanning microscopy, dynamic rheological testing, and Raman spectrum during gelation were further analyzed to investigate the effects of methyl-ß-cyclodextrin on the qualities of epigallocatechin-3-gallate-treated emulsion gel. Methyl-ß-cyclodextrin addition prevented modification of the secondary structure of MPs caused by epigallocatechin-3-gallate. In consequence, the gel and emulsifying properties of MPs were significantly improved. Moreover, ß-cyclodextrins could partly inhibit oxidative attacks on MPs and thus increase their solubility. These results indicated that methyl-ß-cyclodextrin addition effectively enhanced epigallocatechin-3-gallate loading capacity in meat products.


Assuntos
Catequina/análogos & derivados , Proteínas Musculares/química , Miofibrilas/química , Polifenóis/química , beta-Ciclodextrinas/química , Animais , Catequina/química , Emulsões/química , Interações Hidrofóbicas e Hidrofílicas , Miofibrilas/metabolismo , Oxirredução , Ligação Proteica , Solubilidade , Suínos
18.
Sensors (Basel) ; 18(5)2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29748499

RESUMO

A grating-assisted trimodal interferometer biosensor is proposed and numerically analyzed. A long period grating coupler, for adjusting the power between the fundamental mode and the second higher order mode, is investigated, and is shown to act as a conventional directional coupler for adjusting the power between the two arms. The trimodal interferometer can achieve maximal fringe visibility when the powers of the two modes are adjusted to the same value by the grating coupler, which means that a better limit of detection can be expected. In addition, the second higher order mode typically has a larger evanescent tail than the first higher order mode in bimodal interferometers, resulting in a higher sensitivity of the trimodal interferometer. The influence of fabrication tolerances on the performance of the designed interferometer is also investigated. The power difference between the two modes shows inertia to the fill factor of the grating, but high sensitivity to the modulation depth. Finally, a 2050 2π/RIU (refractive index unit) sensitivity and 43 dB extinction ratio of the output power are achieved.

19.
Cell Death Dis ; 9(3): 261, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29449584

RESUMO

The necroptotic cell death pathway is a key component of human pathogen defense that can become aberrantly derepressed during tissue homeostasis to contribute to multiple types of tissue damage and disease. While formation of the necrosome kinase signaling complex containing RIPK1, RIPK3, and MLKL has been extensively characterized, additional mechanisms of its regulation and effector functions likely remain to be discovered. We screened 19,883 mouse protein-coding genes by CRISPR/Cas9-mediated gene knockout for resistance to cytokine-induced necroptosis and identified 112 regulators and mediators of necroptosis, including 59 new candidate pathway components with minimal or no effect on cell growth in the absence of necroptosis induction. Among these, we further characterized the function of PTBP1, an RNA binding protein whose activity is required to maintain RIPK1 protein abundance by regulating alternative splice-site selection.


Assuntos
Processamento Alternativo , Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Fibroblastos/enzimologia , Marcação de Genes/métodos , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Necroptose , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Fibroblastos/patologia , Regulação Enzimológica da Expressão Gênica , Células HEK293 , Células HT29 , Ribonucleoproteínas Nucleares Heterogêneas/genética , Humanos , Camundongos , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Transdução de Sinais
20.
Polymers (Basel) ; 10(6)2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-30966637

RESUMO

Polymers are promising materials for fabricating photonic integrated waveguide devices. Versatile functional devices can be manufactured using a simple process, with low cost and potential mass-manufacturing. This paper reviews the recent progress of polymer photonic integrated devices fabricated using the UV imprinting technique. The passive polymer waveguide devices for wavelength filtering, power splitting, and light collecting, and the active polymer waveguide devices based on the thermal-optic tuning effect, are introduced. Then, the electro-optic (EO) modulators, by virtue of the high EO coefficient of polymers, are described. Finally, the photonic biosensors, which are based on low-cost and biocompatible polymer platforms, are presented.

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