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Ring-fused azacyclic compounds are important building units in the synthesis of biorelevant natural products, pharmaceutical agents, and molecular materials. Herein, we present a new approach to these condensed azacycles by a biomimetic cascade cyclization of arylalkenyl dioxazolones. This cascade reaction was found to proceed with excellent stereoselectivity and a high functional group tolerance. The substrate scope of arylalkenyl dioxazolones turned out to be highly flexible and extendable to additional terminating subunits, such as heteroaryl and alkynyl moieties. This biomimetic cyclization was elucidated to be initiated by an intramolecular transfer of the in situ generated electrophilic Ir-acylnitrenoid to the tethered olefinic double bond, leading to a key N-acylaziridine intermediate, which is in turn reacted with pendant (hetero)arenes or alkynes in a highly regio- and stereoselective manner to produce ring-fused azacyclic compounds.
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As antibiotic resistance has risen as one of the major health concerns associated with infectious diseases due to the reduced efficacy of antibiotics, rapid and sensitive detection of antibiotic resistance genes is critical for more effective and faster treatment of infectious diseases. A class of programmable DNA-binding domains called transcriptional activator-like effectors (TALEs) provides a novel scaffold for designing versatile DNA-binding proteins due to their modularity and predictability. Here, we developed a simple, rapid, and sensitive system for detecting antibiotic resistance genes by exploring the potential of TALE proteins for the creation of a sequence-specific DNA diagnostic along with 2D-nanosheet graphene oxide (GO). TALEs were engineered to directly recognize the specific double-stranded (ds) DNA sequences present in the tetracycline resistance gene (tetM), avoiding the need for dsDNA denaturation and renaturation. We take advantage of the GO as an effective signal quencher to quantum dot (QD)-labeled TALEs for creating a turn-on strategy. QD-labeled TALEs are adsorbed on the GO surface, which will bring QDs in close proximity to GO. Due to the fluorescence quenching ability of GO, QDs are expected to be quenched by GO via fluorescence resonance energy transfer (FRET). QD-labeled TALE binding to the target dsDNA would lead to the conformational change, which would result in dissociation from the GO surface, thereby restoring the fluorescence signal. Our sensing system was able to detect low concentrations of dsDNA sequences in the tetM gene after only 10-minute incubation with the DNA, providing a limit of detection as low as 1 fM of Staphylococcus aureus genomic DNA. This study demonstrated that our approach of utilizing TALEs as a new diagnostic probe along with GO as a sensing platform can provide a highly sensitive and rapid method for direct detection of the antibiotic resistance gene without requiring DNA amplification or labeling.
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Técnicas Biossensoriais , Grafite , Antibacterianos/farmacologia , Grafite/química , DNA/química , Transferência Ressonante de Energia de Fluorescência/métodos , Técnicas Biossensoriais/métodos , Óxidos/químicaRESUMO
The laboratory diagnosis of latent tuberculosis is often performed using interferon-gamma release assays. Here, we compared two enzyme-linked immunosorbent assay-based interferon-gamma release assays, namely, the newly developed Standard E TB-Feron enzyme-linked immunosorbent assay (STFE) and the QuantiFERON-TB Gold PLUS assay (QFT-GP), using samples from 155 participants. The STFE is based on using whole EAST6 and CFP10 recombinant antigens for latent tuberculosis diagnosis. The participants were classified into four groups and screened using both assays per the manufacturers' instructions. Thereafter, two statistical analyses were conducted to compare the obtained results. First, the STFE results were compared with the QTF-GP results (used as the gold standard) to calculate the total concordance, sensitivity, and specificity of STFE. Second, positivity and negativity concordances were calculated to differentiate healthy participants from participants with tuberculosis. The STFE showed 97% and 94% sensitivity and specificity, respectively. Furthermore, its positivity and negativity concordances were 91% and 98%, respectively. These results indicate the coordinated clinical performance of STFE in detecting latent tuberculosis and its improved performance in targeting tuberculosis-infected participants. Based on the comparison of the latent tuberculosis diagnostic abilities of STFE and QFT-GP, we establish the suitability and superior performance of STFE as a diagnostic tool.
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Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose , Humanos , Tuberculose Latente/diagnóstico , Tuberculose/diagnóstico , Testes de Liberação de Interferon-gama/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Sensibilidade e Especificidade , Mycobacterium tuberculosis/genéticaRESUMO
BACKGROUND: Middle East respiratory syndrome (MERS) is a highly lethal respiratory disease caused by a zoonotic betacoronavirus. The development of effective vaccines and control measures requires a thorough understanding of the immune response to this viral infection. METHODS: We investigated cellular immune responses up to 5 years after infection in a cohort of 59 MERS survivors by performing enzyme-linked immunospot assay and intracellular cytokine staining after stimulation of peripheral blood mononuclear cells with synthetic viral peptides. RESULTS: Memory T-cell responses were detected in 82%, 75%, 69%, 64%, and 64% of MERS survivors from 1-5 years post-infection, respectively. Although the frequency of virus-specific interferon gamma (IFN-γ)-secreting T cells tended to be higher in moderately/severely ill patients than in mildly ill patients during the early period of follow-up, there was no significant difference among the different clinical severity groups across all time points. While both CD4+ and CD8+ T cells were involved in memory T-cell responses, CD4+ T cells persisted slightly longer than CD8+ T cells. Both memory CD4+ and CD8+ T cells recognized the E/M/N proteins better than the S protein and maintained their polyfunctionality throughout the period examined. Memory T-cell responses correlated positively with antibody responses during the initial 3-4 years but not with maximum viral loads at any time point. CONCLUSIONS: These findings advance our understanding of the dynamics of virus-specific memory T-cell immunity after MERS-coronavirus infection, which is relevant to the development of effective T cell-based vaccines.
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Infecções por Coronavirus , Coronavírus da Síndrome Respiratória do Oriente Médio , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Humanos , Memória Imunológica , Leucócitos Mononucleares , Células T de Memória , SobreviventesRESUMO
BACKGROUND: Astrocyte is a key regulator of neuronal activity and excitatory/inhibitory balance via gliotransmission. Recently, gliotransmission has been identified as a novel target for neurological diseases. However, using the properties of nanomaterials to modulate gliotransmission has not been uncovered. RESULTS: We prepared non-invasive CNT platforms for cells with different nanotopography and properties such as hydrophilicity and conductivity. Using CNT platforms, we investigated the effect of CNT on astrocyte functions participating in synaptic transmission by releasing gliotransmitters. Astrocytes on CNT platforms showed improved cell adhesion and proliferation with upregulated integrin and GFAP expression. In addition, intracellular GABA and glutamate in astrocytes were augmented on CNT platforms. We also demonstrated that gliotransmitters in brain slices were increased by ex vivo incubation with CNT. Additionally, intracellular resting Ca2+ level, which is important for gliotransmission, was also increased via TRPV1 on CNT platforms. CONCLUSION: CNT can improve astrocyte function including adhesion, proliferation and gliotransmission by increasing resting Ca2+ level. Therefore, our study suggests that CNT would be utilized as a new therapeutic platform for central nervous system diseases by modulating gliotransmission.
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Nanotubos de Carbono , Astrócitos , Encéfalo , Neurônios/metabolismo , Transmissão Sináptica/fisiologiaRESUMO
[Purpose] This study investigated two-point discrimination (TPD) and the electrical sensory threshold of the blind to define the effect of using Braille on the tactile and electrical senses. [Subjects and Methods] Twenty-eight blind participants were divided equally into a text-reading and a Braille-reading group. We measured tactile sensory and electrical thresholds using the TPD method and a transcutaneous electrical nerve stimulator. [Results] The left palm TPD values were significantly different between the groups. The values of the electrical sensory threshold in the left hand, the electrical pain threshold in the left hand, and the electrical pain threshold in the right hand were significantly lower in the Braille group than in the text group. [Conclusion] These findings make it difficult to explain the difference in tactility between groups, excluding both palms. However, our data show that using Braille can enhance development of the sensory median nerve in the blind, particularly in terms of the electrical sensory and pain thresholds.
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To develop a universal coronavirus (CoV) vaccine, long-term immunity against multiple CoVs, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, Middle East respiratory syndrome (MERS)-CoV, and future CoV strains, is crucial. Following the 2015 Korean MERS outbreak, we conducted a long-term follow-up study and found that although neutralizing antibodies and memory T cells against MERS-CoV declined over 5 years, some recovered patients exhibited increased antibody levels during the COVID-19 pandemic. This likely resulted from cross-reactive immunity induced by SARS-CoV-2 vaccines or infections. A significant correlation in antibody responses across various CoVs indicates shared immunogenic epitopes. Two epitopes-the spike protein's stem helix and intracellular domain-were highly immunogenic after MERS-CoV infection and after SARS-CoV-2 vaccination or infection. In addition, memory T cell responses, especially polyfunctional CD4+ T cells, were enhanced during the pandemic, correlating significantly with MERS-CoV spike-specific antibodies and neutralizing activity. Therefore, incorporating these cross-reactive and immunogenic epitopes into pan-CoV vaccine formulations may facilitate effective vaccine development.
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COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , Humanos , COVID-19/epidemiologia , Vacinas contra COVID-19 , Pandemias , Seguimentos , SARS-CoV-2 , Imunidade Adaptativa , EpitoposRESUMO
C1 domains, the recognition motif of the second messenger diacylglycerol and of the phorbol esters, are classified as typical (ligand-responsive) or atypical (not ligand-responsive). The C1 domain of Vav1, a guanine nucleotide exchange factor, plays a critical role in regulation of Vav activity through stabilization of the Dbl homology domain, which is responsible for exchange activity of Vav. Although the C1 domain of Vav1 is classified as atypical, it retains a binding pocket geometry homologous to that of the typical C1 domains of PKCs. This study clarifies the basis for its failure to bind ligands. Substituting Vav1-specific residues into the C1b domain of PKCδ, we identified five crucial residues (Glu(9), Glu(10), Thr(11), Thr(24), and Tyr(26)) along the rim of the binding cleft that weaken binding potency in a cumulative fashion. Reciprocally, replacing these incompatible residues in the Vav1 C1 domain with the corresponding residues from PKCδ C1b (δC1b) conferred high potency for phorbol ester binding. Computer modeling predicts that these unique residues in Vav1 increase the hydrophilicity of the rim of the binding pocket, impairing membrane association and thereby preventing formation of the ternary C1-ligand-membrane binding complex. The initial design of diacylglycerol-lactones to exploit these Vav1 unique residues showed enhanced selectivity for C1 domains incorporating these residues, suggesting a strategy for the development of ligands targeting Vav1.
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Diglicerídeos/metabolismo , Ésteres de Forbol/metabolismo , Proteínas Proto-Oncogênicas c-vav/química , Proteínas Proto-Oncogênicas c-vav/metabolismo , Sequência de Aminoácidos , Linhagem Celular Tumoral , Humanos , Lactonas/metabolismo , Ligantes , Masculino , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fosfolipídeos/metabolismo , Neoplasias da Próstata , Ligação Proteica/fisiologia , Proteína Quinase C-delta/metabolismo , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-vav/genética , Transdução de Sinais/fisiologiaRESUMO
The recent progress in nanoparticle applications, such as tumor-targeting, has enabled specific delivery of chemotherapeutics to malignant tissues with enhanced local efficacy while limiting side effects. However, existing delivery systems leave much room for improvement in terms of achieving enhanced colloidal stability in fluid medium, efficient targeting of intended sites, and effective release of therapeutic drugs into diseased cells. Here, an efficient stimuli-responsive nanocarrier for mammalian cells, termed RGD-NAMs, was developed, which enabled temperature- and pH-sensitive release of drug loads. The RGD-NAMs comprise two parts: a stimuli-responsive copolymer shell (NIBIm-AA-RGD) and drug-container core (MSNs). The RGD-NAMs have a stable drug-loading capacity with a marked difference in the release rate depending on the temperature and pH conditions. The RGD-NAMs also exhibit high colloidal stability in SBF (Stimulated body fluid) solutions and minimal toxicity in skeletal myoblasts (C2C12) and bovine arterial endothelial cells (BAEC). The doxorubicin-loaded RGD-NAMs induced a cytotoxic effect in a dose-dependent manner, which was furthered by an increase in temperature from 37 to 40 °C. Moreover, significant control of the release rate and the amount were achieved through pH change. This novel, smart drug-delivery system with high responsiveness to temperature and pH changes has wide application prospects in biomedical fields, including the theragnosis of tumors and vascular diseases.
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Nanopartículas , Neoplasias , Animais , Bovinos , Humanos , Portadores de Fármacos/farmacologia , Dióxido de Silício , Células Endoteliais , Sistemas de Liberação de Medicamentos , Doxorrubicina/farmacologia , Nanopartículas/uso terapêutico , Oligopeptídeos , Concentração de Íons de Hidrogênio , Porosidade , MamíferosRESUMO
Sensors, such as optical, chemical, and electrical sensors, play an important role in our lives. While these sensors already have widespread applications, such as humidity sensors, most are generally incompatible with flexible/inactive substrates and rely on conventional hard materials and complex manufacturing processes. To overcome this, we develop a CNT-based, low-resistance, and flexible humidity sensor. The core-shell structured CNT@CPM is prepared with Chit and PAMAM to achieve reliability, accuracy, consistency, and durability, resulting in a highly sensitive humidity sensor. The average response/recovery time of optimized sensor is only less than 20 s, with high sensitivity, consistent responsiveness, good linearity according to humidity rates, and low hysteresis (- 0.29 to 0.30 %RH). Moreover, it is highly reliable for long-term (at least 1 month), repeated bending (over 15,000 times), and provides accurate humidity measurement results. We apply the sensor to smart-wear, such as masks, that could conduct multi-respiratory monitoring in real-time through automatic ventilation systems. Several multi-respiratory monitoring results demonstrate its high responsiveness (less than 1.2 s) and consistent performance, indicating highly desirable for healthcare monitoring. Finally, these automatic ventilation systems paired with flexible sensors and applied to smart-wear can not only provide comfort but also enable stable and accurate healthcare in all environments.
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Smart hydrogels that are responsive to various external (e.g. electrical and/or thermal) stimulation have become increasingly popular in recent years for simple, rapid, and precise drug delivery that can be controlled and turned on or off with external stimuli. For such a switchable drug delivery material, highly homogeneous dispersion and distribution of the hydrophobic, electrically conductive nanomaterials throughout a hydrophilic three-dimensional (3D) hydrogel network remains a challenge and is essential for achieving well-connected electrical and thermal conducting paths. Herein we developed electrical and thermal stimulus-responsive 3D hydrogels based on (i) carbon nanotubes (CNTs) as the core unit and an electrical/thermal conductor, (ii) chitosan (Chit) as the shell unit and a hydrophilic dispersant, and (iii) poly(NIPAAm-co-BBVIm) (pNIBBIm) as the drug carrier and a temperature-responsive copolymer. By formulating the CNT-core and Chit-shell units and constructing a CNT sponge framework, uniform distribution and 3D connectivity of the CNTs were improved. The 3D hydrogel based on the CNT sponge, namely the 3D frame CNT-Chit/pNIBBIm hydrogel, delivered approximately 37% of a drug, ketoprofen used for the treatment of musculoskeletal pain, during about 30% shrinkage after electrical and thermal switches on/off and exhibited the best potential for future use in a smart transdermal drug delivery system. The physicochemical, mechanical, electrical, thermal, and biocompatible characteristics of this nanocarbon-based 3D frame hydrogel led to remarkable electrical and thermal stimulus-responsive properties capable of developing an excellent controllable and switchable drug delivery platform for biomedical engineering and medicine applications.
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Quitosana , Nanotubos de Carbono , Condutividade Elétrica , Hidrogéis , PolímerosRESUMO
OBJECTIVE: CCL23 [Ckß8-1/myeloid progenitor inhibitory factor 1 (MPIF1)/macrophage inflammatory protein-3 (MIP3)], a member of the CC chemokine family, is involved in leukocyte trafficking, and implicated in inflammatory diseases. In the present study, we investigated the role of CCL23 in the development of human atherosclerosis, which is characterized by an inflammatory disease. METHODS: CCL23 transcripts were measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and CCL23 protein by immunohistochemistry and enzyme-linked immunosorbent assay (ELISA). Expression of adhesion molecules was determined by flow cytometry, and matrix metalloproteinase-2 (MMP-2) levels by zymography. RESULTS: Proatherogenic factors such as oxidized low-density lipoprotein (oxLDL) and oxidative stress markedly enhanced CCL23 release from human THP-1 macrophages. CCL23 stimulated chemotaxis of human THP-1 monocytes in a dose-dependent manner and enhanced the expression of adhesion molecule CD11c, as well as release of MMP-2 from the THP-1 monocytes. Moreover, CCL23 expression at the mRNA level was significantly higher in human atherosclerotic lesions than in normal arteries, and CCL23 protein was co-expressed with CD68, a specific marker for macrophages. Circulating levels of plasma CCL23 were higher in atherosclerotic patients than in normal subjects. CONCLUSION: These findings suggest that CCL23 plays a role in the development of human atherosclerosis. CCL23 may be a useful target for the development of antiatherogenic agents.
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Aterosclerose/imunologia , Aterosclerose/patologia , Moléculas de Adesão Celular/metabolismo , Quimiocinas CC/imunologia , Quimiotaxia/fisiologia , Metaloproteinase 2 da Matriz/metabolismo , Monócitos/metabolismo , Animais , Aterosclerose/sangue , Antígeno CD11c/metabolismo , Células Cultivadas , Quimiocina CCL2/metabolismo , Quimiocinas CC/sangue , Quimiocinas CC/genética , Feminino , Humanos , Lipoproteínas LDL/metabolismo , Masculino , Monócitos/citologia , Estresse OxidativoRESUMO
We aimed to evaluate muscle mass changes after injection of botulinum toxin (BoNT) in children with spastic hemiplegic cerebral palsy (CP). Children aged between 2 and 12 years who were diagnosed with hemiplegic CP with spastic equinus foot were prospectively recruited and administered BoNT in the affected leg. Lean body mass (LBM) of both legs and total limbs was measured by dual-energy X-ray absorptiometry (DXA) preinjection and 4 and 12 weeks after injection. A total of 15 children were enrolled into the study. LBM of both legs and total limbs increased significantly over 12 weeks of growth. The ratio of LBM of the affected leg to total limbs and to the unaffected leg significantly reduced at 4 weeks after injection compared with preinjection but significantly increased at 12 weeks after injection compared with 4 weeks after injection. In conclusion, the muscle mass of the affected leg after BoNT injection in children with hemiplegic spastic CP decreased at 4 weeks after BoNT injection but significantly recovered after 12 weeks after injection.
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Toxinas Botulínicas Tipo A/administração & dosagem , Paralisia Cerebral/tratamento farmacológico , Hemiplegia/tratamento farmacológico , Músculo Esquelético/efeitos dos fármacos , Fármacos Neuromusculares/administração & dosagem , Absorciometria de Fóton , Fatores Etários , Toxinas Botulínicas Tipo A/efeitos adversos , Paralisia Cerebral/diagnóstico , Paralisia Cerebral/fisiopatologia , Criança , Pré-Escolar , Feminino , Hemiplegia/diagnóstico , Hemiplegia/fisiopatologia , Humanos , Injeções Intramusculares , Masculino , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/crescimento & desenvolvimento , Fármacos Neuromusculares/efeitos adversos , Estudos Prospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
In this research, alternative deposition process of ZnO-based thin films have been studied for transparent conducting oxide (TCO) application. To improve the electrical and optical properties of transparent oxide thin films, alternatively stacked Al-doped ZnO and In-doped ZnO thin films were investigated. Multilayer structure of alternative 6 layers of thin films were prepared in this research. Especially, Aluminum and Indium were chosen as dopant materials. Thin films of Al-doped ZnO (AZO) and In-doped ZnO (IZO) were alternatively deposited by spin coating with sol-gel method. After deposition of multilayered thin films, multi steps of furnace (F), rapid thermal annealing (R) and CO2 laser annealing (L) processes were carried out and investigated thin film properties by dependence of post-annealing sequence and thin film structures. The electrical and optical properties of thin films were investigated by 4-point probe and UV-vis spectroscopy and its shows the greatest sheet resistance value of 0.59 kΩ/sq. from AZO/IZO multilayered structure and upper 85% of transmittance. The structural property and surface morphology were measured by X-Ray Diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The Al- and In-doped ZnO thin film shows the highest intensity value at (002) peak of AZO/IZO multilayer structure which was performed FRL process.
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A series of DAG-lactones with polar 3-alkylidene substituents have been investigated as PKC-alpha ligands and antitumor agents. Extensive analysis of structure-activity relationships for the 3-alkylidene chain revealed that polar groups such as ether, hydroxyl, aldehyde, ester, acyloxy, and amido were tolerated with similar binding affinities and reduced lipophilicities compared to the corresponding unsubstituted alkylidene chain. Among the derivatives, compounds 5, 6 and 8 with an ether type of side chain showed high binding affinities in range of K(i)= 3-5 nM and excellent antitumor profiles, particularly against the colo205 colon cancer and the K562 leukemia cell lines.
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4-Butirolactona/análogos & derivados , Antineoplásicos/química , Antineoplásicos/metabolismo , Proteína Quinase C/metabolismo , Valeratos/química , Valeratos/metabolismo , 4-Butirolactona/química , 4-Butirolactona/metabolismo , Células HL-60 , Humanos , Células K562 , Lactonas/química , Lactonas/metabolismo , LigantesRESUMO
It may be difficult to diagnose congenital osseous torticollis based on physical examinations or plain X-rays, especially when children have no other accompanying congenital defects. This study reports the children with torticollis caused by the vertebral anomaly with the symptom of abnormal head and neck posture only. We retrospectively reviewed the records of 1015 patients diagnosed with congenital torticollis in a single tertiary hospital (Incheon St. Mary's Hospital, Korea) who were referred from a primary local clinic. We included those with deficits in passive range of motion (PROM) of neck. Ultrasonography of the sternocleidomastoid (SCM) muscles, ophthalmologic and neurologic examinations, and cervical X-rays were performed for all patients. If bony malalignment was suspected from X-ray, three-dimensional volume-rendered computed tomography (3D-CT) was performed. Ten patients were diagnosed with osseous torticollis with no defect other than bony anomalies. Although X-ray images were acquired for all patients, vertebral anomalies were definitely confirmed in three cases (30.0%) only, and the others (70.0%) were confirmed by CT. The most common type of vertebral anomaly was single-level fusion. Identifying congenital vertebral anomalies is challenging especially when the degree of invasion is only one level. Although abnormal findings on X-rays may be subtle, a careful examination must be performed to avoid misdiagnosis.
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In this study, Ga-doped ZnO thin films were prepared, and their potential for transparent conducting oxide applications was assessed. To increase the electrical mobility and reduce the resistance of Ga-doped ZnO thin films, CO2 laser annealing was employed. Recently, the use of transparent conducting oxides (TCOs) have increased, particularly ZnO-based TCOs have been intensively investigated for display applications. To enhance the electrical and optical properties of ZnO thin films, Ga was used as a dopant. First, Ga-doped ZnO thin-film precursors were prepared by the sol-gel method. Subsequently, Ga-doped ZnO thin films were coated on glass substrates by spin coating. Electrical furnace treatment and rapid thermal annealing were employed to obtain and anneal a wurtzite ZnO based structure. The electrical and optical properties of the annealed thin films were optimized by varying the Ga doping concentration. Via Ga doping and optimized laser annealing, the resistivity of the ZnO film could be decreased from 16.32 Ω· cm to 0.45 Ω·cm; notably, the transmittance was similar (85%) in the 380-800 nm range. The transmittance properties of the films are not presented in this paper. Moreover, after an optical CO2 laser annealing process, the conductivity of the films improved by more than 40 times. Furthermore, the electrical properties (mobility, resistivity, and bulk and sheet concentrations) of the CO2-laser-annealed Ga-doped ZnO thin films were optimized.
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Light Emitting Diodes (LED) are highly energy efficient and offer long-life times for display applications. Long life and minimal energy consumption are often the most attractive advantages for electronic devices. Because LEDs are based on compound semiconductors, which explore the direct transition between the conduction and valance band edges, thermal energy loss can be minimized during operation. However, even though these types of LEDs are based on direct transition type semiconductors, thermal energy is still emitted during operation owing to forward conduction and reverse leakage currents. This research proposes capturing this energy loss through thermoelectric module-based energy recycling methods to improve the energy efficiency of LED applications, achieving savings of up to 18%. Additional analysis was performed on high power LED sources resulting in the manufacture of a high-power LED light grid system.
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A leucine-rich repeat receptor-like kinase (LRR-RLK) encoded by one of the genes highly expressed in a specific stage of soybean seed development, referred to as GmLRK1, was identified and characterized. Examination of its kinase domain indicated that GmLRK1 may be a catalytically inactive atypical receptor kinase. An autophosphorylation assay confirmed that GmLRK1 is incapable of autophosphorylation in vitro. However, the phosphorylation of GmRLK1 could be induced after incubation with plant protein extracts, suggesting that some plant proteins may interact with GmLRK1 and phosphorylate the protein in vivo. Analyses of the expression profiles of GmLRK1 and its Arabidopsis ortholog At2g36570 revealed that they may be involved in regulation of more fundamental metabolic and/or developmental pathways, rather than a specialized developmental program such as seed development. Our results further indicate that the GmLRK1 and At2g36570 may play a role in the regulation of certain cellular processes that lead to cell elongation and expansion.
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Crescimento Celular , Glycine max/citologia , Glycine max/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas de Soja/genética , Sequência de Aminoácidos , Arabidopsis/citologia , Arabidopsis/enzimologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , DNA Complementar/química , DNA Complementar/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Hibridização In Situ , Dados de Sequência Molecular , Mutação , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sementes/enzimologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Proteínas de Soja/metabolismo , Glycine max/enzimologiaRESUMO
OBJECTIVE: To investigate chemokines and their receptors gene expression in the intra-abdominal adipose tissue of diabetic/obese mice. METHODS: KKAy mice were fed either by a high-fat diet (HFD) or a low-fat diet (LFD) and obese characteristics were analyzed. Various adipose tissues were isolated from HFD-fed obese KKAy mice and from obese controls. We carried out RT-PCR, GeneChip microarray, and real-time PCR analyses on samples derived from the adipose tissues. RESULTS: The HFD-feded obese KKAy mice had the physiological characteristics of obese animal and had increased levels of the transcripts of several chemokine and chemokine receptor genes, such as CCL5, CCL19, CCL25, CXCL10, CXCL13, CCR6, and CCR7, in their intra-abdominal adipose tissue. The strong expression of CCR6 and CCR7 was verified by microarray and quantitative real-time PCR analysis. The HFD increased CCR6 and CCR7 expression only in mesenteric (ME) adipose tissue, not in subcutaneous (SC) adipose tissue. DISCUSSION: Since the enhanced expression of such molecules is likely to contribute to the inflammation in chronic inflammatory disease, our data suggest that the increased levels of CCR6 and CCR7 are involved in the inflammation response in the intra-abdominal adipose tissue of the obese/diabetic mice.