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1.
J Nat Prod ; 87(1): 58-67, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38159296

RESUMO

Phytochemical investigation of the MeOH extract of Pinus eldarica needles led to the isolation and identification of a new clerodane-type diterpene, pinuseldarone (1), along with a known flavonoid, 5,4'-dihydroxy-3,7,8-trimethoxy-6-C-methylflavone (2), through HPLC purification. The structure of the new compound 1 was elucidated using spectroscopic methods, including 1D and 2D NMR, as well as HRESIMS. Its absolute configuration was established through NOESY analysis and computational methods, including electronic circular dichroism (ECD) calculations and gauge-including atomic orbital NMR chemical shift calculations, followed by DP4+ probability analysis. The metabolic implications of the isolated compounds were assessed using a cultured brown adipocyte model derived from murine brown adipose tissue. It was observed that treatment with dihydroxy-3,7,8-trimethoxy-6-C-methylflavone (2) downregulates the adipogenic marker C/EBPδ and fatty acid transporter CD36, resulting in a significant reduction in lipid accumulation during brown adipocyte differentiation. However, pinuseldarone (1) treatment did not affect brown adipocyte differentiation. Interestingly, pretreatment with pinuseldarone (1) potentiated the pharmacological stimulation of brown adipocytes, seemingly achieved by sensitizing their response to ß3-adrenoreceptor signaling. Therefore, our findings indicate that phytochemicals derived from P. eldarica needles could potentially serve as valuable compounds for adjusting the metabolic activity of brown adipose tissue, a vital component in maintaining whole-body metabolic homeostasis.


Assuntos
Diterpenos Clerodânicos , Pinus , Animais , Camundongos , Adipogenia , Adipócitos Marrons/metabolismo , Termogênese
2.
Cell Rep ; 42(12): 113541, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-38060444

RESUMO

Neuroblastoma originates from developing neural crest and can interconvert between the mesenchymal (MES) and adrenergic (ADRN) states, each of which are controlled by different sets of transcription factors forming the core regulatory circuit (CRC). However, the roles of CRC factors in induction and maintenance of specific state are poorly understood. Here, we demonstrate that overexpression of ASCL1, an ADRN CRC factor, in MES neuroblastoma cells opens closed chromatin at the promoters of key ADRN genes, accompanied by epigenetic activation and establishment of enhancer-promoter interactions, initiating the ADRN gene expression program. ASCL1 inhibits the transforming growth factor ß-SMAD2/3 pathway but activates the bone morphogenetic protein SMAD1-ID3/4 pathway. ASCL1 and other CRC members potentiate each other's activity, increasing the expression of the original targets and inducing a new set of genes, thereby fully inducing the ADRN program. Our results demonstrate that ASCL1 serves as a pioneer factor and cooperates with CRC factors to characterize the ADRN gene expression program.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Neuroblastoma , Humanos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Adrenérgicos , Fatores de Transcrição/metabolismo , Regiões Promotoras Genéticas/genética , Neuroblastoma/genética , Neuroblastoma/metabolismo
3.
bioRxiv ; 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37905014

RESUMO

Transposon-derived transcripts are abundant in RNA sequences, yet their landscape and function, especially for fusion transcripts derived from unannotated or somatically acquired transposons, remains underexplored. Here, we developed a new bioinformatic tool to detect transposon-fusion transcripts in RNA-sequencing data and performed a pan-cancer analysis of 10,257 cancer samples across 34 cancer types as well as 3,088 normal tissue samples. We identified 52,277 cancer-specific fusions with ~30 events per cancer and hotspot loci within transposons vulnerable to fusion formation. Exonization of intronic transposons was the most prevalent genic fusions, while somatic L1 insertions constituted a small fraction of cancer-specific fusions. Source L1s and HERVs, but not Alus showed decreased DNA methylation in cancer upon fusion formation. Overall cancer-specific L1 fusions were enriched in tumor suppressors while Alu fusions were enriched in oncogenes, including recurrent Alu fusions in EZH2 predictive of patient survival. We also demonstrated that transposon-derived peptides triggered CD8+ T-cell activation to the extent comparable to EBV viruses. Our findings reveal distinct epigenetic and tumorigenic mechanisms underlying transposon fusions across different families and highlight transposons as novel therapeutic targets and the source of potent neoantigens.

4.
J Vis Exp ; (200)2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37870308

RESUMO

Brown adipose tissue (BAT) plays a crucial role in regulating metabolic homeostasis through a unique energy expenditure process known as non-shivering thermogenesis. To achieve this, BAT utilizes a diverse menu of circulating nutrients to support its high metabolic demand. Additionally, BAT secretes metabolite-derived bioactive factors that can serve as either metabolic fuels or signaling molecules, facilitating BAT-mediated intratissue and/or intertissue communication. This suggests that BAT actively participates in systemic metabolite exchange, an interesting feature that is beginning to be explored. Here, we introduce a protocol for in vivo mouse-level optimized BAT arteriovenous metabolomics. The protocol focuses on relevant methods for thermogenic stimulations and an arteriovenous blood sampling technique using Sulzer's vein, which selectively drains interscapular BAT-derived venous blood and systemic arterial blood. Next, a gas chromatography-based metabolomics protocol using those blood samples is demonstrated. The use of this technique should expand the understanding of BAT-regulated metabolite exchange at the inter-organ level by measuring the net uptake and release of metabolites by BAT.


Assuntos
Tecido Adiposo Marrom , Metabolismo Energético , Camundongos , Animais , Tecido Adiposo Marrom/metabolismo , Termogênese/fisiologia , Homeostase , Transdução de Sinais
5.
BMB Rep ; 56(10): 569-574, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37605616

RESUMO

Aberrant DNA methylation plays a pivotal role in the onset and progression of colorectal cancer (CRC), a disease with high incidence and mortality rates in Korea. Several CRC-associated diagnostic and prognostic methylation markers have been identified; however, due to a lack of comprehensive clinical and methylome data, these markers have not been validated in the Korean population. Therefore, in this study, we aimed to obtain the CRC methylation profile using 172 tumors and 128 adjacent normal colon tissues of Korean patients with CRC. Based on the comparative methylome analysis, we found that hypermethylated positions in the tumor were predominantly concentrated in CpG islands and promoter regions, whereas hypomethylated positions were largely found in the open-sea region, notably distant from the CpG islands. In addition, we stratified patients by applying the CpG island methylator phenotype (CIMP) to the tumor methylome data. This stratification validated previous clinicopathological implications, as tumors with high CIMP signatures were significantly correlated with the proximal colon, higher prevalence of microsatellite instability status, and MLH1 promoter methylation. In conclusion, our extensive methylome analysis and the accompanying dataset offers valuable insights into the utilization of CRC-associated methylation markers in Korean patients, potentially improving CRC diagnosis and prognosis. Furthermore, this study serves as a solid foundation for further investigations into personalized and ethnicity-specific CRC treatments. [BMB Reports 2023; 56(10): 569-574].


Assuntos
Neoplasias Colorretais , Metilação de DNA , Humanos , Metilação de DNA/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Ilhas de CpG/genética , República da Coreia , Fenótipo
6.
Food Sci Biotechnol ; 31(3): 365-376, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35273827

RESUMO

Benzyl chloride is a harmful chemical that contaminates air, water, and food. A static headspace GC-MS method for determining benzyl chloride in food was developed and validated. Two food matrices (fat/oil and chicken) were used for method validation. Sample preparation involved ultrasonication extraction and purification (syringe filtration). Linearity (R 2) was > 0.99, accuracy ranged from 86.91% to 110%, the limit of detection was 0.04-0.17 mg/kg, and the limit of quantification was 0.13-0.52 mg/kg. Recovery varied from 88.19% to 111.77%, and precision ranged from 0.10% to 1.17% in intraday and interday analyses. Among 102 food items (oils, fats, meat, marine, and egg products) distributed in Korea, benzyl chloride was only detected in six of the marine products. The validated analytical method can be used for routine monitoring of benzyl chloride residues in food and thereby prevent the human health risks associated with the consumption of food contaminated with this chemical.

7.
Lang Speech ; 65(3): 531-553, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34399633

RESUMO

This exploratory study investigates the acoustic correlates of the Korean three-way laryngeal stop distinction in Gyeongsang long-term (LT) transplants who were born in the Gyeongsang region but moved to Seoul to pursue higher education. Acoustic data were collected from eight LT transplants, five short-term (ST) transplants, and 11 Seoul speakers to examine whether exposure to Seoul Korean (SK) affects Gyeongsang speakers' cue-weighting in distinguishing stops in production. LT transplants produced stimuli in both Gyeongsang and Seoul dialects. A cue-weighting model based on the acoustic data reveals that voice onset time (VOT) is less important to distinguish lenis from aspirated stops for Seoul speakers and for LT transplants' SK, as compared to ST transplants and LT transplants' Gyeongsang Korean (GK). In addition, fundamental frequency (F0) is more important for the lenis-aspirated distinction for Seoul speakers and LT transplants' SK, as compared to ST and LT transplants' GK, showing that LT transplants rely less on VOT and more on F0 to distinguish lenis from aspirated stops compared to ST transplants. LT transplants' SK reveals that they rely more on VOT and less on F0 compared to SK speakers. The cue-weighting model of the LT transplants provide empirical evidence that a series of sound changes in GK is due to inter-dialect contact.


Assuntos
Idioma , Voz , Acústica , Humanos , Fonética , Seul , Acústica da Fala
8.
J Dermatol Sci ; 104(2): 83-94, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34690024

RESUMO

BACKGROUND: Urban pollution is correlated with an increased prevalence of skin pigmentation disorders, however the physiological processes underlying this association are unclear. OBJECTIVES: To delineate the relationship between polycyclic aromatic hydrocarbons (PAHs), a key constituent of atmospheric pollution, and immunity/skin pigmentation pathways. METHODS: We exposed peripheral blood mononuclear cells (PBMC) to PAHs and performed cytokines/chemokine profiling. We then examined the effect of immune activation on pigmentation by co-culturing PBMC and Benzo(a)pyrene (BaP) with reconstructed human pigmented epidermis (RHPE). To study the mechanism, we treated keratinocytes with conditioned medium from BaP-exposed PBMC and studied DNA damage responses, aryl hydrocarbon receptor (AhR) activation and pro-pigmentation factor, proopiomelanocortin (POMC) secretion. RESULTS: PAHs induced up-regulation of inflammatory cytokines/chemokine in PBMC. Co-culturing of RHPE with PBMC+BaP resulted in increased melanin content and localization. BaP-conditioned medium significantly increased DNA damage, p53 stabilization, AhR activation and POMC secretion in keratinocytes. We found that IFNγ induced DNA damage, while TNFα and IL-8 potentiated POMC secretion in keratinocytes. Importantly, BaP-conditioned medium-induced DNA damage and POMC secretion is prevented by antioxidants vitamin E, vitamin C and sulforaphane, as well as the prototypical corticosteroid dexamethasone. Finally, vitamin C and sulforaphane enhanced the genome protective and depigmentation effects of dexamethasone, providing proof-of-concept for a combinatorial approach for the prevention and/or correction of PAH-induced pigment spots formation. CONCLUSION: Our study reveals the importance of systemic immunity in regulating PAH-induced skin pigmentation, and provide a new keratinocyte DNA damage response mechanistic target for the prevention or reversal of pollution-associated skin pigmentation.


Assuntos
Antioxidantes/farmacologia , Citocinas/metabolismo , Reparo do DNA , Hidrocarbonetos Policíclicos Aromáticos/imunologia , Pigmentação da Pele/efeitos dos fármacos , Pigmentação da Pele/imunologia , Anti-Inflamatórios/farmacologia , Ácido Ascórbico/farmacologia , Benzo(a)pireno/farmacologia , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Dano ao DNA/efeitos dos fármacos , Dexametasona/farmacologia , Epiderme , Humanos , Fenômenos do Sistema Imunitário , Interferon gama/metabolismo , Interleucina-8/metabolismo , Isotiocianatos/farmacologia , Queratinócitos , Leucócitos Mononucleares , Melaninas/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Pró-Opiomelanocortina/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Sulfóxidos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Vitamina E/farmacologia
9.
J Acoust Soc Am ; 149(6): 3703, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34241448

RESUMO

We investigate whether acoustic cue weightings are transferred from the native language to the second language [research question 1 (RQ1)], how cue weightings change with increasing second-language proficiency (RQ2), and whether individual cues are used independently or together in the second language (RQ3). Vowel reduction is a strong cue to lexical stress in English but not Dutch. Native English listeners and Dutch second-language learners of English completed a cue-weighting stress perception experiment. Participants heard sentence-final pitch-accented auditory stimuli and identified them as DEsert (initial stress) or deSSERT (final stress). The stimuli were manipulated in seven steps from initial to final stress, manipulating two dimensions at a time: vowel quality and pitch, vowel quality and duration, and pitch and duration (other dimensions neutralized). Dutch listeners relied less on vowel quality and more on pitch than English listeners, with Dutch listeners' sensitivity to vowel quality increasing with English proficiency but their sensitivity to pitch not varying with proficiency; Dutch listeners evidenced similar or weaker reliance on duration than did English listeners, and their sensitivity to duration increased with proficiency; and Dutch listeners' use of pitch and duration were positively related. These results provide general support for a cue-based transfer approach to the perception of lexical stress.


Assuntos
Sinais (Psicologia) , Percepção da Fala , Humanos , Idioma , Fonética , Acústica da Fala
10.
J Colloid Interface Sci ; 600: 740-751, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34052529

RESUMO

Designing a novel composite material with hierarchical nanostructures as a negative electrode material with high capacitance and outstanding stability is challenging. To this end, we synthesized carbon nanotubes (CNTs)-protected vanadium phosphate (VPO) nanoparticles trapped within an electrospun carbon matrix (CNTs@VPO@CNFs) for potential use in energy storage applications. Temperature was found to be the major controlling factor for the fabrication of composites with CNT decoration. CNTs@VPO@CNFs exhibited the highest capacitance of 576.1F g-1 at a current density of 0.66 A g-1 among other corresponding electrode materials. Furthermore, this electrode exhibited outstanding stability of up to 99% after 5000 cycles, which was attributed to the coating of core-forming VPO@CNFs by the CNTs as the sheath material. Interestingly, the as-fabricated material worked in a wide potential range from -1.2 to 0.6, thereby providing the opportunity to assemble a symmetric supercapacitor device (SSCD). The SSCD showed an exceptionally high energy density of 69.1 W h kg-1 at a power density of 3.2 kW h and ~ 90% stability after 5000 cycles. Thus, this work presents a strategy for fabricating a new composite as a negative electrode material that can be used in a symmetrical supercapacitor device with an ultrahigh energy density.

11.
ACS Appl Mater Interfaces ; 13(20): 23732-23742, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33977710

RESUMO

The fabrication of an economic and efficient multifunctional advanced nanomaterial with a rational composition and configuration by a facile methodology is a crucial challenge. Herein, we are the first to report the growth of Co nanoparticle-integrated nitrogen-doped carbon nanotubes (N-CNTs) on porous carbon nanofibers by simply heating in the situ-developed metal-organic framework (MOF)-based electrospun nanofibrous membrane with no need for an external supply of any additional precursors and reducing gases. The long and entangled N-CNTs originating from highly porous and graphitic carbon nanofibers offer good flexibility, large surface area, high porosity, high conductivity, the homogeneous incorporation of heteroatoms and metallic constituents, and an abundant exposure of active nanocatalytic sites. The as-developed nanoassembly demonstrates attractive characteristics for electrocatalytic hydrogen and oxygen evolution reactions and electrochemical energy storage. This strategy of integrating the essence of an MOF with electrospinning offers a new, direct, and cost-effective approach for making N-doped CNT-based multifunctional membranes.

12.
J Korean Med Sci ; 36(7): e49, 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33619917

RESUMO

BACKGROUND: The risk of tick-borne diseases is decreased by increasing awareness and knowledge through prevention education. The aim of the present study was to evaluate the effect of long-lasting permethrin impregnated (LLPI) socks for tick bites. METHODS: A randomized open label study was conducted to determine the effectiveness of LLPI socks for prevention of tick bites among 367 adults living in a rural area. Participants completed questionnaires at the start of follow-up (July 2014) and at the end of follow-up (December 2014), and tick bites were reported. RESULTS: A total of 332 subjects completed the follow-up survey. The tick bite rate of the two groups was not significantly different (3.6% vs. 3.1%). But the tick bite rate of lower extremities of subjects wearing LLPI socks was significantly lower compared to that of subjects wearing general socks. CONCLUSION: The tick bite rate was not different between the two groups, but the tick bite rate of lower extremities of LLPI was significantly lower than general groups. Further study is needed to investigate the effect of LLPI clothes with larger populations.


Assuntos
Inseticidas/farmacologia , Permetrina/farmacologia , Roupa de Proteção , Picadas de Carrapatos/prevenção & controle , Carrapatos/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Conhecimento , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Tifo por Ácaros/patologia , Tifo por Ácaros/prevenção & controle , Inquéritos e Questionários , Picadas de Carrapatos/epidemiologia
13.
J Vet Sci ; 21(4): e52, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32735091

RESUMO

BACKGROUND: Intradural-intramedullary intervertebral disc extrusion (IIVDE) is a rare condition of intervertebral disc disease. However, the diagnosis of IIVDE is challenging because the prognosis and imaging characteristics are poorly characterized. OBJECTIVES: We aimed to describe the clinical and imaging characteristics of tentatively diagnosed IIVDE in dogs to assess the prognostic utility of neurological grade and magnetic resonance imaging (MRI) findings. METHODS: Twenty dogs were included in this retrospective cohort study. RESULTS: Nonchondrodystrophic breeds (n = 16) were more predisposed than chondrodystrophic breeds. Most dogs showed acute onset of clinical signs. Neurological examination at admission showed predominant non-ambulatory paraparesis (n = 9); paresis (n = 16) was confirmed more frequently than paralysis (n = 4). Follow-up neurological examination results were only available for 11 dogs, ten of whom showed neurological improvement and 8 showed successful outcomes at 1 month. The characteristic MRI findings include thoracic vertebra (T)2 hyperintense, T1 hypointense, intramedullary linear tracts with reduced disc volume, and cleft of the annulus fibrosus. None of the MRI measurements were significantly correlated with neurological grade at admission. Neurological grade did not differ according to the presence of parenchymal hemorrhage, parenchymal contrast enhancement, and meningeal contrast enhancement. Neurological grades at admission showed a statistical correlation with those observed at the 1-month follow-up (r = 0.814, p = 0.02). CONCLUSIONS: IIVDE is a rare form of disc extrusion commonly experienced after physical activity or trauma and most frequently affects the cranial-cervical and thoracolumbar regions of nonchondrodystrophic dog breeds. Neurological score at admission emerged as a more useful prognostic indicator than MRI findings in dogs with suspected IIVDE.


Assuntos
Doenças do Cão/diagnóstico , Degeneração do Disco Intervertebral/veterinária , Deslocamento do Disco Intervertebral/veterinária , Vértebras Torácicas/patologia , Animais , Doenças do Cão/diagnóstico por imagem , Cães , Feminino , Degeneração do Disco Intervertebral/diagnóstico , Degeneração do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/diagnóstico , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Imageamento por Ressonância Magnética/veterinária , Masculino , Estudos Retrospectivos , Vértebras Torácicas/diagnóstico por imagem
14.
J Phycol ; 56(6): 1696-1711, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32725784

RESUMO

Giant clams harbor three genera of symbiotic dinoflagellates (Symbiodinium, Cladocopium, and Durusdinium) as extracellular symbionts (zooxanthellae). While symbiotic dinoflagellates can synthesize amino acids to benefit the host, they are nitrogen-deficient. Hence, the host must supply them with nitrogen including urea, which can be degraded to ammonia and carbon dioxide by urease (URE). Here, we report three complete coding cDNA sequences of URE, one for each genus of dinoflagellate, obtained from the colorful outer mantle of the giant clam, Tridacna squamosa. The outer mantle had higher transcript level of Tridacna squamosa zooxanthellae URE (TSZURE) than the whitish inner mantle, foot muscle, hepatopancreas, and ctenidium. TSZURE was immunolocalized strongly and atypically in the plastid, moderately in the cytoplasm, and weakly in the cell wall and plasma membrane of symbiotic dinoflagellates. In the outer mantle, illumination upregulated the protein abundance of TSZURE, which could enhance urea degradation in photosynthesizing dinoflagellates. The urea-nitrogen released could then augment synthesis of amino acids to be shared with the host for its general needs. Illumination also enhanced gene and protein expression levels of TSZURE/TSZURE in the inner mantle and foot muscle, which contain only small quantities of symbiotic dinoflagellate, have no iridocyte, and lack direct exposure to light. With low phototrophic potential, dinoflagellates in the inner mantle and foot muscle might need to absorb carbohydrates in order to assimilate the urea-nitrogen into amino acids. Amino acids donated by dinoflagellates to the inner mantle and the foot muscle could be used especially for synthesis of organic matrix needed for light-enhanced shell formation and muscle protein, respectively.


Assuntos
Bivalves , Dinoflagellida , Animais , Dinoflagellida/genética , Iluminação , Simbiose , Urease
15.
Nanoscale Adv ; 2(10): 4918-4929, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36132926

RESUMO

Transition metal phosphate (TMPi)-based composites as anode electrode materials in supercapacitor applications are less reported. Herein, we report a phytic acid (PA)-assisted in situ-formed amorphous cobalt phosphate/carbon (CoPi/C) composite grown on a flexible woven carbon cloth (CC) via a simple one-step carbonization approach. The tunable synthesis of amorphous and crystalline composites is shown by simply controlling the concentration of the cobalt salts. The strategy for high mass loading to 12 mg cm-2 is also shown in this report. Importantly, the resulting amorphous electrode materials exhibit electric double-layer capacitance (EDLC) behavior that works over a wide potential range from -1.4 to +0.5 V in an aqueous solution of potassium hydroxide (2 M KOH) and from -1.5 to +1.5 V in sodium sulfate (1 M Na2SO4). The amorphous electrode as an anode is capable of delivering an areal capacitance up to 2.15 F cm-2 at a current density of 4 mA cm-2 (gravimetric capacitance up to 606.1 F g-1 at 1 Ag-1) and has a retention of 94.2% at 10 000 cycles. The flexible solid-state symmetric device fabricated shows an energy density of approximately 620.0 µW h cm-2 at a power density of 4.7 mW cm-2 (31.1 W h kg-1 at 476.0 W kg-1). This study offers a novel route for the generation of metal phosphate-based anode materials with high capacitance for symmetrical supercapacitor device with high energy density.

16.
Nano Lett ; 19(10): 7534-7539, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31490079

RESUMO

Future scalable and integrated quantum photonic systems require deterministic generation and control of multiple quantum emitters. Although various approaches for spatial and spectral control of the quantum emitters have been developed, on-chip control of both position and frequency is still a long-standing goal in solid-state quantum emitters. Here, we demonstrate simultaneous control of position and frequency of the quantum emitters from transition metal dichalcogenide monolayers. Atomically thin two-dimensional materials are inherently sensitive to external strain and offer a new opportunity of creating and controlling the quantum emitters by engineering strain. We fabricate an electrostatically actuated microcantilever with nanopyramid patterns, providing a local strain engineering platform for the WSe2 monolayer. The integrated WSe2 generates high-purity single photon emission at patterned positions with a tuning range up to 3.5 meV. Together with the position and frequency control, we investigate the strain response on the fine-structure splitting and confirm 11% reduction in the fine splitting at the estimated tensile strain of 0.07%.

18.
Enzyme Microb Technol ; 107: 7-14, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28899489

RESUMO

Inefficient transport of xylose into Saccharomyces cerevisiae is a major hurdle for production of xylitol, a natural sweetener with five carbons. To facilitate the xylose transport and hence increase xylose conversion to xylitol, the araE gene encoding an arabinose:H+ symporter (AraE) from Bacillus subtilis and the XYL1 gene from Scheffersomyces stipitis were expressed in Saccharomyces cerevisiae EBY.VW4000, a hxt null mutant. The resulting strain of EXHA exhibited 4.1 fold increases in xylose consumption rate and xylitol productivity, relative to the control strain without AraE. Also, overexpression of AraE in wild type S. cerevisiae D452-2 having all hexose transporters and the XYL1 gene increased both xylose consumption and xylitol production considerably. In a glucose-limited fed-batch culture with intermittent addition of xylose, the DXXA strain with multiple copies of araE and XYL1 produced 177.8g/L xylitol with 2.47g/L-h productivity, which were 26.9 and 17.6 times higher than those for a batch culture of the DX strain expressing the XYL1 gene only, respectively. It was concluded that B. subtilis AraE might be a potent xylose transporter and conferred much higher xylose-consuming and xylitol-producing abilities to S. cerevisiae.


Assuntos
Aldeído Redutase/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Xilitol/biossíntese , Xilose/metabolismo , Aldeído Redutase/genética , Arabinose/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Técnicas de Cultura Celular por Lotes , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Cinética , Proteínas de Transporte de Monossacarídeos/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/genética , Saccharomycetales/metabolismo
19.
J Korean Med Sci ; 31(10): 1656-61, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27550497

RESUMO

The aim of this study was to investigate the efficiency of domestic physician-staffed helicopter emergency medical service (HEMS) for the transport of patients with severe trauma to a hospital. The study included patients with blunt trauma who were transported to our hospital by physician-staffed HEMS (Group P; n = 100) or nonphysician-staffed HEMS (Group NP; n = 80). Basic patient characteristics, transport time, treatment procedures, and medical treatment outcomes assessed using the Trauma and Injury Severity Score (TRISS) were compared between groups. We also assessed patients who were transported to the hospital within 3 h of injury in Groups P (Group P3; n = 50) and NP (Group NP3; n = 74). The severity of injury was higher, transport time was longer, and time from hospital arrival to operation room transfer was shorter for Group P than for Group NP (P < 0.001). Although Group P patients exhibited better medical treatment outcomes compared with Group NP, the difference was not statistically significant (P = 0.134 vs. 0.730). However, the difference in outcomes was statistically significant between Groups P3 and NP3 (P = 0.035 vs. 0.546). Under the current domestic trauma patient transport system in South Korea, physician-staffed HEMS are expected to increase the survival of patients with severe trauma. In particular, better treatment outcomes are expected if dedicated trauma resuscitation teams actively intervene in the medical treatment process from the transport stage and if patients are transported to a hospital to receive definitive care within 3 hours of injury.


Assuntos
Despacho de Emergência Médica/métodos , Ferimentos e Lesões/patologia , Adulto , Resgate Aéreo , Feminino , Pessoal de Saúde , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , República da Coreia , Análise de Sobrevida , Centros de Atenção Terciária , Fatores de Tempo , Resultado do Tratamento , Ferimentos e Lesões/mortalidade
20.
Biotechnol J ; 11(11): 1443-1451, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27440394

RESUMO

The protein-stabilizing and cell-penetrating activities of Bombyx mori 30Kc19 α-helix domain (30Kc19α) are investigated. Recently, 30Kc19 protein has been studied extensively as it has both protein-stabilizing and cell-penetrating properties. However, it is unknown which part of 30Kc19 is responsible for those properties. 30Kc19 protein is composed of two distinct domains, an α-helix N-terminal domain (30Kc19α) and a ß-trefoil C-terminal domain (30Kc19ß). The authors construct and produce truncated forms of 30Kc19 to demonstrate their biological functions. Interestingly, 30Kc19α was shown to be responsible for both the protein-stabilizing and cell-penetrating properties of 30Kc19 protein. 30Kc19α shows even higher protein delivery activity than did whole 30Kc19 protein and has low cytotoxicity when added to cell culture medium. Therefore, based on its multifunctional properties, 30Kc19α can be developed as a novel candidate for a therapeutic protein carrier into various cells and tissues.


Assuntos
Bombyx/genética , Peptídeos Penetradores de Células/química , Sistemas de Liberação de Medicamentos , Proteínas de Insetos/química , Animais , Bombyx/química , Peptídeos Penetradores de Células/genética , Regulação da Expressão Gênica , Humanos , Proteínas de Insetos/genética , Proteínas de Insetos/uso terapêutico , Conformação Proteica em alfa-Hélice , Domínios Proteicos , Estabilidade Proteica
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