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While monoradical emitters have emerged as a new route toward efficient organic light-emitting diodes, the luminescence property of organic diradicaloids is still scarcely explored. Herein, by devising a novel radical-radical coupling-based synthetic approach, we report a new class of sulfone-functionalized Chichibabin's hydrocarbon derivatives, SD-1-3, featuring varied substituent patterns and moderate to high diradical characters of 0.44-0.70, as highly stable diradicaloids with rarely seen NIR emission beyond 900 nm. Via comprehensive experimental and theoretical investigations, we reveal that the optoelectronic and magnetic properties of these materials are significantly tuned by the variations of substitutions (H/CF3/OMe) on the molecular skeletons. More importantly, quantum chemical computations indicate that the embedding of sulfone groups has contributed to a breaking of their quasi-C2 symmetry of these diradicaloid molecules and results in an excited-state charge transfer character. Therefore, a remarkably deep NIR emissive wavelength of up to 998 nm, together with a large Stokes shift (â¼386 nm), is achieved for the CF3-based SD-2 molecule in tetrahydrofuran. To the best of our knowledge, such a luminescent wavelength of SD-2 has represented the longest wavelengths among the currently reported organic fluorescent radicals. Overall, our work not only establishes a new synthetic approach toward stable Chichibabin's hydrocarbons but also paves the way for designing NIR emissive open-shell materials with both fundamental understanding and feasible control of their luminescent properties.
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New stimulus-responsive scaffolds are of interest as constituents of hierarchical supramolecular ensembles. 1,3,5-2,4,6-Functionalized, facially segregated benzene moieties have a time-honored role as building blocks for host molecules. However, their user as switchable motifs in the construction of multi-component supramolecular structures remains poorly explored. Here, we report a molecular cageâ 1, which consists of a bent anthracene dimer 3 paired with 1,3,5-tris(aminomethyl)-2,4,6-triethylbenzene 2. As the result of the pH-induced abababâbababa isomerization of the constituent-functionalized benzene units derived from 2, this cage can reversibly convert between an open state and a closed form, both in solution and in the solid state. Cageâ 1 was used to create stimuli-responsive hierarchical superstructures, namely Russian doll-like complexes with [Kâ18-crown-6â1]+ and [Kâcryptand-222â1]+. The reversible assembly and disassembly of these superstructures could be induced by switching cageâ 1 from its open to closed form. The present study thus provides an unusual example where pH-triggered conformation motion within a cage-like scaffold is used to control the formation and disassociation of hierarchical ensembles.
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We describe the application of a novel, bispecific antibody platform termed dual affinity retargeting (DART) to eradicate B-cell lymphoma through coengagement of the B cell-specific antigen CD19 and the TCR/CD3 complex on effector T cells. Comparison with a single-chain, bispecific antibody bearing identical CD19 and CD3 antibody Fv sequences revealed DART molecules to be more potent in directing B-cell lysis. The enhanced activity with the CD19xCD3 DART molecules was observed on all CD19-expressing target B cells evaluated using resting and prestimulated human PBMCs or purified effector T-cell populations. Characterization of a CD19xTCR bispecific DART molecule revealed equivalent potency with the CD19xCD3 DART molecule, demonstrating flexibility of the DART structure to support T-cell/B-cell associations for redirected T cell-killing applications. The enhanced level of killing mediated by DART molecules was not accompanied by any increase in nonspecific T-cell activation or lysis of CD19(-) cells. Cell-association studies indicated that the DART architecture is well suited for maintaining cell-to-cell contact, apparently contributing to the high level of target cell killing. Finally, the ability of the CD19xTCR DART to inhibit B-cell lymphoma in NOD/SCID mice when coadministered with human PBMCs supports further evaluation of DART molecules for the treatment of B-cell malignancies.
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Anticuerpos Biespecíficos/inmunología , Anticuerpos Biespecíficos/farmacología , Linfocitos B/inmunología , Linfoma de Células B , Linfocitos T/inmunología , Animales , Antígenos CD19/inmunología , Antígenos CD19/metabolismo , Linfocitos B/citología , Complejo CD3/inmunología , Complejo CD3/metabolismo , Comunicación Celular/inmunología , Línea Celular Tumoral , Femenino , Humanos , Linfocinas/inmunología , Linfoma de Células B/tratamiento farmacológico , Linfoma de Células B/inmunología , Linfoma de Células B/patología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Sialoglicoproteínas/inmunología , Linfocitos T/citología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The root of Angelica sinensis (Oliv.) Diels (abbreviated as AS) (Danggui) has a long history in Asian herbal medicine. Recently, it was demonstrated that AS possesses anti-cancer and anti-oxidant activities. Because the transcription factor Nrf2 mediates the expression of many cellular anti-oxidative stress genes, including genes that are involved in phase II drug metabolism and anti-oxidative stress, this study sought to investigate whether pure compounds from AS or an AS extract could activate antioxidant response element (ARE)-mediated gene expression and induce anti-inflammatory activities. Z-Ligustilide (Ligu), 3-butylidenephthalide (Buty) and CO2 supercritical fluid-extracted lipophilic AS extract (SFE) were tested in HepG2-C8 cells stabilized with ARE luciferase reporter gene. Ligu and Buty caused significant toxicity only at 100 µm. All three samples induced ARE-luciferase activity; however, SFE at 8.5 µg/ml induced ARE-luciferase activity 2-3 fold more potently than did either of the pure compounds. SFE also significantly increased the endogenous mRNA of Nrf2 and the Nrf2 target anti-oxidative gene NAD(P)H dehydrogenase, quinone 1 (NQO1). The protein expression of NQO1 was also significantly induced by SFE. In RAW 264.7 cells, SFE suppressed lipopolysaccharide (LPS)-induced IL-1ß and TNF-α expression about 2 fold stronger than sulforaphane, whereas both pure compounds and SFE suppressed inflammatory nitric oxide (NO) production. In summary, this study demonstrates that AS has anti-inflammatory effects and activates the Nrf2 pathway, which protects against oxidative stress.
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4-Butirolactona/análogos & derivados , Angelica sinensis , Antiinflamatorios/farmacología , Factor 2 Relacionado con NF-E2/genética , Anhídridos Ftálicos/farmacología , Extractos Vegetales/farmacología , 4-Butirolactona/farmacología , Animales , Línea Celular Tumoral , Expresión Génica , Células Hep G2 , Humanos , Interleucina-1beta/metabolismo , Ratones , NAD(P)H Deshidrogenasa (Quinona)/genética , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Óxido Nítrico/metabolismo , Fitoquímicos/farmacología , ARN Mensajero/metabolismo , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa-1 , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Fu Rong Ye (FRY), the leaf of Hibiscus mutabilis L., is a Chinese medicinal herb used to treat coughs and respiratory diseases. FRY is the major herbal component of the patent medicine Fupo Ganmao Granules for treating common cold. However, its anti-influenza active components and mechanism were not identified. AIM: Here, we aim to a) isolate the anti-influenza phytochemicals from FRY extract and b) explore its anti-flu mechanism. MATERIAL AND METHODS: Bioassay guided isolation was performed to get anti-influenza virus components. Influenza virus infected cells and mouse model were employed for efficacy evaluation. RESULTS: Using bioassay-guided isolation, the flavonoid tiliroside was obtained, which inhibited four IAV strains in MDCK cells with EC50 ranging from 3.87 to 27.61 µM by suppressing the viral ribonucleoprotein activity. Tiliroside also significantly downregulated the expression of cytokines/chemokines in A549 cells, and protected 50% of PR8-infected BALB/c mice from death and at 800 mg/kg/day, improved lung edema conditions. CONCLUSION: Tiliroside is effective for influenza virus infection treatment and promising for further drug development. This study is the first to demonstrate that tiliroside in FRY acts against influenza virus.
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Hibiscus , Gripe Humana , Animales , Perros , Ratones , Humanos , Antivirales/farmacología , Antivirales/uso terapéutico , Gripe Humana/tratamiento farmacológico , Flavonoides , Células de Riñón Canino Madin DarbyRESUMEN
The detrimental impact of obesity on human health is increasingly evident with the rise in obesity-related diseases. Skeletal muscle, the crucial organ responsible for energy balance metabolism, plays a significant role as a secretory organ by releasing various myokines. Among these myokines, interleukin 6 (IL-6) is closely associated with skeletal muscle contraction. IL-6 triggers the process of lipolysis by mobilizing energy-storing adipose tissue, thereby providing energy for physical exercise. This phenomenon also elucidates the health benefits of regular exercise. However, skeletal muscle and adipose tissue maintain a constant interaction, both directly and indirectly. Direct interaction occurs through the accumulation of excess fat within skeletal muscle, known as ectopic fat deposition. Indirect interaction takes place when adipose tissue is mobilized to supply the energy for skeletal muscle during exercise. Consequently, maintaining a functional balance between skeletal muscle and adipose tissue becomes paramount in regulating energy metabolism and promoting overall health. IL-6, as a representative cytokine, participates in various inflammatory responses, including non-classical inflammatory responses such as adipogenesis. Skeletal muscle influences adipogenesis through paracrine mechanisms, primarily by secreting IL-6. In this research paper, we aim to review the role of skeletal muscle-derived IL-6 in lipid metabolism and other physiological activities, such as insulin resistance and glucose tolerance. By doing so, we provide valuable insights into the regulatory function of skeletal muscle-derived myokines in lipid metabolism.
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The assessment of population genetic structure is the basis for understanding the genetic information of indigenous breeds and is important for the protection and management of indigenous breeds. However, the population genetic differentiation of many local breeds still remains unclear. Here, we performed a genome-wide comparative analysis of Jinding, Liancheng white, Putian black, and Shanma ducks based on the genomic sequences using RAD sequencing to understand their population structure and genetic diversity. The population parameters showed that there were obvious genetic differences among the four indigenous breeds, which were separated groups. Among them, Liancheng white and Shanma ducks may come from the same ancestor because the phylogenetic tree forms three tree trunks. In addition, during the runs of homozygosity (ROH), we found that the average inbreeding coefficient of Liancheng white and Putian black ducks was the lowest and the highest, respectively. Five genomic regions were considered to be the hotspots of autozygosity among these indigenous duck breeds, and the candidate genes involved a variety of potential variations, such as muscle growth, pigmentation, and neuroregulation. These findings provide insights into the further improvement and conservation of Fujian duck breeds.
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ETHNOPHARMACOLOGICAL RELEVANCE: Canarium album (Lour.) DC. belongs to the Burseraceae family. Its leaf, named as Ganlanye (GLY), was recorded to treat warm disease symptoms via clearing lung heat and toxicants in medical classics. Its aqueous extract had anti-influenza activity in our previous phenotypic screening. However, its active components and mechanism were not identified. AIM: We aim to isolate the anti-influenza phytochemicals from GLY extract and explore its anti-flu mechanism. MATERIAL AND METHODS: Influenza A virus infected MDCK cells were used to test the compounds and fractions. Structural analyses of new compounds were performed via NMR calculation with the combination of DP4plus probability method and computed electronic circular dichroism (ECD). Hemagglutination inhibitory assay and neuraminidase inhibitory assay were performed to find the target protein. Molecular docking and recombinant virus were used to confirm the action site of the three new canaroleosides. RESULTS: Three new phenolic glycosides, canaroleosides A-C (1-3), and three known flavonoids (4-6), were isolated from the GLY aqueous extract and their anti-influenza virus mechanism was revealed. The absolute configurations of 1-3 were determined by ECD method, with the structure of the 2,5-dihydroxybenzoic acid moiety in 1 assigned by NMR calculation. Compound 1 was found to suppress both hemagglutinin and neuraminidase activities. Compounds 2, 3 4 and 6 inhibited neuraminidase, while compound 5 inhibited hemagglutinin. 1-3 could interact with Arg152 of the viral neuraminidase based on the result of molecular docking and reverse genetics. CONCLUSION: Six phytochemicals were isolated from GLY aqueous extract and found to inhibit influenza A strains. They were found to interact with hemagglutinin or neuraminidase and canaroleosides 1-3 could interact with Arg152 of the viral neuraminidase. This study provided more evidence on the anti-influenza effect of Ganlan and laid the foundation for further generation of potent NA inhibitors.
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Burseraceae , Gripe Humana , Antivirales , Burseraceae/química , Hemaglutininas , Humanos , Simulación del Acoplamiento Molecular , Neuraminidasa , Fitoquímicos/farmacología , Extractos Vegetales/farmacologíaRESUMEN
Luffin P1, the smallest ribosome-inactivating peptide from the seeds of Luffa cylindrica was found to have anti-HIV-1 activity in HIV-1 infected C8166 T-cell lines and be able to bind with HIV Rev Response Element. Nuclear magnetic resonance spectroscopy revealed that the Luffin P1 comprises a helix-loop-helix motif, with the two alpha helices tightly associated by two disulfide bonds. Based on our findings, we conclude that unlike the well-studied ribosome-inactivating proteins, which exert their action through N-glycosidase activities, Luffin P1 demonstrates a novel inactivation mechanism probably through the charge complementation with viral or cellular proteins. Our work also provides a new scaffold for the design of novel inhibitors from a simple helical motif.
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Fármacos Anti-VIH/química , Luffa/química , Péptidos/química , Semillas/química , Fármacos Anti-VIH/farmacología , Dicroismo Circular , Ensayo de Cambio de Movilidad Electroforética , Ensayo de Inmunoadsorción Enzimática , Genes env/genética , VIH-1/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Péptidos/farmacologíaRESUMEN
INTRODUCTION: Response to trastuzumab in metastatic breast cancer correlates with expression of the high binding variant (158V) of the activating Fcγ receptor IIIA (CD16A). We engineered MGAH22, a chimeric anti-HER2 monoclonal antibody with specificity and affinity similar to trastuzumab, with an Fc domain engineered for increased binding to both alleles of human CD16A. METHODS: MGAH22 was compared to an identical anti-HER2 mAb except for a wild type Fc domain. Antibody-dependent cell cytotoxicity (ADCC) assays were performed with HER2-expressing cancer cells as targets and human PBMC or purified NK cells as effectors. Xenograft studies were conducted in mice with wild type murine FcγRs; in mice lacking murine CD16; or in mice lacking murine CD16 but transgenic for human CD16A-158F, the low-binding variant. The latter model reproduces the differential binding between wild type and the Fc-optimized mAb for human CD16A. The JIMT-1 human breast tumor line, derived from a patient that progressed on trastuzumab therapy, was used in these studies. Single and repeat dose toxicology studies with MGAH22 administered intravenously at high dose were conducted in cynomolgus monkeys. RESULTS: The optimized Fc domain confers enhanced ADCC against all HER2-positive tumor cells tested, including cells resistant to trastuzumab's anti-proliferative activity or expressing low HER2 levels. The greatest improvement occurs with effector cells isolated from donors homozygous or heterozygous for CD16A-158F, the low-binding allele. MGAH22 demonstrates increased activity against HER2-expressing tumors in mice transgenic for human CD16A-158F. In single and repeat-dose toxicology studies in cynomolgus monkeys, a species with a HER2 expression pattern comparable to that in humans and Fcγ receptors that exhibit enhanced binding to the optimized Fc domain, MGAH22 was well tolerated at all doses tested (15-150 mg/kg) and exhibited pharmacokinetic parameters similar to that of other anti-HER2 antibodies. Induction of cytokine release by MGAH22 in vivo or in vitro was similar to that induced by the corresponding wild type mAb or trastuzumab. CONCLUSIONS: The data support the clinical development of MGAH22, which may have utility in patients with low HER2 expressing tumors or carrying the CD16A low-binding allele.
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Anticuerpos Monoclonales/farmacología , Antineoplásicos/farmacología , Receptor ErbB-2/antagonistas & inhibidores , Receptores de IgG/metabolismo , Animales , Anticuerpos Monoclonales/metabolismo , Anticuerpos Monoclonales/toxicidad , Anticuerpos Monoclonales Humanizados/farmacología , Citotoxicidad Celular Dependiente de Anticuerpos , Antineoplásicos/metabolismo , Antineoplásicos/toxicidad , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Macaca fascicularis , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Neoplasias/metabolismo , Unión Proteica , Receptor ErbB-2/inmunología , Receptor ErbB-2/metabolismo , TrastuzumabRESUMEN
OBJECTIVE: To study the absorption mechanism of tanshinones in the roots of Salvia miltiorrhiza as well as the interaction between the components in the effective fraction. METHOD: The model of intestinal absorption in vivo was used and the concentrations of the tanshinones were determined by HPLC, the apparent absorption constant (K(a)) and half life of absorption (t1/2) were obtained, the other components in the extract on the absorption of the there components were also studied. RESULT: With the increase of dosage of tanshinone II A or cryptotanshinone, K(a) decreased and absorption half life t1/2 increased, the drug absorption rate constant (K(a)) had little significant effect on duodenum, Jejunum and ileum. Tanshinone I has a good absorbing in the rat small intestine. The absorption of tanshinone II A and cryptotanshinone was promoted by the other components in tanshinones extract while tanshinone I' was decreased. CONCLUSION: When the concentration increases to a certain level, the uptake of tanshinone II A and cryptotanshinone do not increase. The transport mechanism of tanshinone II A and cryptotanshinone in vivo is similar to active transport or facilitated diffusion. They could be well absorbed in general intestinal tract without specific absorption site, and the complex constituents in extract could significant effect the absorption of the pharmaceutical effective constituents.
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Medicamentos Herbarios Chinos/farmacocinética , Intestino Delgado/fisiología , Fenantrenos/farmacocinética , Salvia miltiorrhiza/química , Abietanos , Absorción , Animales , Medicamentos Herbarios Chinos/análisis , Intestino Delgado/efectos de los fármacos , Masculino , Fenantrenos/análisis , Ratas , Ratas Sprague-DawleyRESUMEN
Plants and crops are widely suffered by shade stress in the natural communities or in the agricultural fields. The three main phytohormones auxin, gibberellins (GAs) and brassinosteroids (BRs) were found essential in shade avoidance in Arabidopsis. However, their relationship have been seldom reported in plant shade avoidance control. Here, we report our investigation of the crosstalk of auxin, GAs and BRs in shade-induced hypocotyl elongation of soybean. Exogenous feeding of indol-3-acetic acid (IAA), GA3 or 24-epibrassinolide (EBL) distinctly promoted hypocotyl elongation in the white light, while the potent biosynthesis inhibitors of GA3, IAA, BRs severely diminished shade-induced hypocotyl elongation. Synergistic treatment of their biosynthesis inhibitors showed that GA3 fully, while EBL slightly, restored the hypocotyl elongation that was efficiently repressed by IAA biosynthesis inhibitor, GA3 and IAA dramatically suppressed the hypocotyl growth inhibition by BR biosynthesis inhibitor in the shade, whereas both IAA and EBL feeding cannot suppress the elongation inhibition by GA biosynthesis inhibitor. Further analyses revealed that shade remarkably upregulated expression of key genes of IAA, GA and BR biosynthesis in the soybean hypocotyls, and GA biosynthesis genes were effectively blocked by IAA, GA and BR biosynthesis inhibitors in the shade. Taken together, these results suggest that GAs modulate shade-induced hypocotyl elongation downstream of mutual promotion of auxin and BRs in soybean.
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Proteínas de Arabidopsis , Brasinoesteroides , Giberelinas , Hipocótilo , Ácidos Indolacéticos , Proteínas de Arabidopsis/genética , Brasinoesteroides/farmacología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Giberelinas/farmacología , Hipocótilo/efectos de los fármacos , Hipocótilo/crecimiento & desarrollo , Ácidos Indolacéticos/metabolismo , Mutación , Reguladores del Crecimiento de las Plantas/farmacología , Glycine max/efectos de los fármacosRESUMEN
Preparation of color-tunable and stable plasmonic MoO3 nanomaterials remains challenging, due to the lack of an effective preparation strategy and surface protection in heavily doped MoO3. Herein, we report a facile and reliable method for synthesis of oxygen-deficient MoO3 (MoO3-x ) nanosheets using dopamine as the reducing agent and precursor for the formation of a polydopamine (PDA) surface coating. The PDA-coated MoO3-x nanosheets show stable and tunable localized surface plasmon resonance (LSPR) from the ultraviolet to the near-infrared region (361-809 nm) via altering the pH value of the medium, accompanying the generation of multicolor nanosheet dispersions, such as deep blue, faint bluish, orange, yellow and black. Importantly, the resulting PDA-coated MoO3-x nanosheets are quite stable even in the presence of oxidants, and they can be used as an ultrasensitive surface-enhanced Raman scattering (SERS) substrate. The limit of detection for rhodamine 6G (R6G) dye is down to 0.3 fM concentration, and the corresponding Raman enhancement factor reaches 1 × 1010. The coupling of charge transfer between R6G and PDA-coated MoO3-x nanosheets and molecular resonances may be responsible for the strong SERS effect.
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Halogenated solvents are prevailingly used in the fabrication of nonfullerene organic solar cells (NF-OSCs) at the current stage, imposing significant restraints on their practical applications. By copolymerizing phthalimide or thieno[3,4-c]pyrrole-4,6-dione (TPD) with 1,4-di(3-alkoxy-2-thienyl)-2,5-difluorophenylene (DOTFP), which features intramolecular noncovalent interactions, the backbone planarity of the resulting DOTFP-based polymers can be effectively tuned, yielding distinct solubilities, aggregation characters, and chain packing properties. Polymer DOTFP-PhI with a more twisted backbone showed a lower degree of aggregation in solution but an increased film crystallinity than polymer DOTFP-TPD. An organic thin-film transistor and NF-OSC based on DOTFP-PhI, processed with a nonhalogenated solvent, exhibited a high hole mobility up to 1.20 cm2 V-1 s-1 and a promising power conversion efficiency up to 10.65%, respectively. The results demonstrate that DOTFP is a promising building block for constructing wide bandgap polymers and backbone coplanarity tuning is an effective strategy to develop high-performance organic semiconductors processable with a nonhalogenated solvent.
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In this study, the highly-ordered TiO(2) nanotube (TNT) arrays on titanium sheets were prepared by an anodic oxidation method. Under UV illumination, the TNT films demonstrated the higher photocatalytic activity in terms of 2,3-dichlorophenol (2,3-DCP) degradation in aqueous solution than the conventional TiO(2) thin films prepared by a sol-gel method. The effects of dissolved oxygen (DO) and pH on the photocatalytic degradation of 2,3-DCP were investigated. The results showed that the role of DO in the 2,3-DCP degradation with the TNT film was significant. It was found that 2,3-DCP in alkaline solution was degraded and dechlorinated faster than that in acidic solution whereas dissolved organic carbon removal presented an opposite order in dependence of pH. In the meantime, some main intermediate products from 2,3-DCP degradation were identified by a (1)H NMR technique to explore a possible degradation pathway. A major intermediate, 2-chlororesorcinol, was identified from the 2,3-DCP decomposition as a new species compared to the findings in previous reports. Photocatalytic deactivation was also evaluated in the presence of individual anions (NO(3)(-), Cl(-), SO(4)(2-), and H(2)PO(4)(-)). The inhibition degree of photocatalytic degradation of 2,3-DCP caused by these anions can be ranked from high to low as SO(4)(2-)>Cl(-)>H(2)PO(4)(-)>NO(3)(-). The observed inhibition effect can be attributed to the competitive adsorption and the formation of less reactive radicals during the photocatalytic reaction.
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Clorofenoles/química , Nanotubos/química , Oxígeno/química , Fármacos Fotosensibilizantes/química , Titanio/química , Aniones/química , Catálisis , Concentración de Iones de Hidrógeno , FotoquímicaRESUMEN
The influenza virus RNA genome is transcribed and replicated in the context of the viral ribonucleoprotein (vRNP) complex by the viral RNA polymerase. The nucleoprotein (NP) is the structural component of the vRNP providing a scaffold for the viral RNA. In the vRNP as well as during transcription and replication the viral polymerase interacts with NP but it is unclear which parts of the polymerase and NP mediate these interactions. Previously the C-terminal '627' domain (amino acids 538-693) of PB2 was shown to interact with NP. Here we report that a fragment encompassing amino acids 146-185 of NP is sufficient to mediate this interaction. Using NMR chemical shift perturbation assays we show that amino acid region 601 to 607 of the PB2 '627' domain interacts with this fragment of NP. Substitutions of these PB2 amino acids resulted in diminished RNP activity and surface plasmon resonance assays showed that amino acids D605 was essential for the interaction with NP and V606 may also play a partial role in the interaction. Collectively these results reveal a possible interaction surface between NP and the PB2 subunit of the RNA polymerase complex.
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Subtipo H5N1 del Virus de la Influenza A/química , Subtipo H5N1 del Virus de la Influenza A/genética , Proteínas de Unión al ARN/química , Proteínas de Unión al ARN/genética , ARN Polimerasa Dependiente del ARN/química , ARN Polimerasa Dependiente del ARN/genética , Proteínas del Núcleo Viral/química , Proteínas del Núcleo Viral/genética , Proteínas Virales/química , Proteínas Virales/genética , Sustitución de Aminoácidos , Ácido Aspártico/química , Genoma Viral , Células HEK293 , Humanos , Subtipo H5N1 del Virus de la Influenza A/fisiología , Gripe Humana/virología , Modelos Moleculares , Resonancia Magnética Nuclear Biomolecular , Proteínas de la Nucleocápside , Dominios y Motivos de Interacción de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Resonancia por Plasmón de Superficie , Valina/química , Replicación ViralRESUMEN
We have developed MGD007 (anti-glycoprotein A33 x anti-CD3), a DART protein designed to redirect T cells to target gpA33 expressing colon cancer. The gpA33 target was selected on the basis of an antibody-based screen to identify cancer antigens universally expressed in both primary and metastatic colorectal cancer specimens, including putative cancer stem cell populations. MGD007 displays the anticipated-bispecific binding properties and mediates potent lysis of gpA33-positive cancer cell lines, including models of colorectal cancer stem cells, through recruitment of T cells. Xenograft studies showed tumor growth inhibition at doses as low as 4 µg/kg. Both CD8 and CD4 T cells mediated lysis of gpA33-expressing tumor cells, with activity accompanied by increases in granzyme and perforin. Notably, suppressive T-cell populations could also be leveraged to mediate lysis of gpA33-expressing tumor cells. Concomitant with CTL activity, both T-cell activation and expansion are observed in a gpA33-dependent manner. No cytokine activation was observed with human PBMC alone, consistent with the absence of gpA33 expression on peripheral blood cell populations. Following prolonged exposure to MGD007 and gpA33 positive tumor cells, T cells express PD-1 and LAG-3 and acquire a memory phenotype but retain ability to support potent cell killing. In cynomolgus monkeys, 4 weekly doses of 100 µg/kg were well tolerated, with prolonged PK consistent with that of an Fc-containing molecule. Taken together, MGD007 displays potent activity against colorectal cancer cells consistent with a mechanism of action endowed in its design and support further investigation of MGD007 as a potential novel therapeutic treatment for colorectal cancer. Mol Cancer Ther; 17(8); 1761-72. ©2018 AACR.
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Neoplasias Colorrectales/tratamiento farmacológico , Inmunoterapia/métodos , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Femenino , Haplorrinos , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Metástasis de la NeoplasiaRESUMEN
Pituitary adenylate cyclase-activating polypeptide (PACAP) has been proposed to be the ancestral GHRH. Recently, using grass carp as a model for modern-day bony fish, we demonstrated that PACAP nerve fibers are present in close proximity to carp somatotrophs, and mammalian PACAPs can induce GH secretion in carp pituitary cells. To further examine the role of PACAP as a GH-releasing factor in fish, the structural identity of grass carp PACAP was established by molecular cloning. The newly cloned PACAP was found to be a single-copy gene and expressed in the brain but not other tissues. The mature peptides of PACAP, namely PACAP(27) and PACAP(38), were synthesized. As revealed by nuclear magnetic resonance spectroscopies, carp PACAP(38) is composed of a flexible N terminal from His(1) to Ile(5), an extended central helix from Phe(6) to Val(26), and a short helical tail in the C terminal from Arg(29) to Arg(34). The C-terminal helix is located after a hinge region at Leu(27) to Gly(28) and is absent in the solution structures of PACAP(27). The two forms of PACAPs were effective in elevating GH release and GH transcript expression in grass carp pituitary cells. These stimulatory effects occurred with parallel rises in cAMP and Ca(2+) entry via voltage-sensitive Ca(2+) channels in carp somatotrophs. The present study represents the first report for solution structures of nonmammalian PACAPs and provides evidence that a brain-specific isoform of PACAP in fish can stimulate GH synthesis and release at the pituitary level, presumably by activating the appropriate postreceptor signaling mechanisms.
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Encéfalo/metabolismo , Carpas/fisiología , Expresión Génica , Hormona Liberadora de Hormona del Crecimiento/fisiología , Hormona del Crecimiento/metabolismo , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Calcio/metabolismo , Células Cultivadas , Dicroismo Circular , Clonación Molecular , AMP Cíclico/biosíntesis , Femenino , Hormona del Crecimiento/genética , Membranas Intracelulares/metabolismo , Espectroscopía de Resonancia Magnética , Masculino , Datos de Secuencia Molecular , Concentración Osmolar , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/genética , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/farmacología , Hipófisis/citología , Hipófisis/efectos de los fármacos , Hipófisis/metabolismo , Isoformas de Proteínas/fisiología , ARN Mensajero/metabolismo , Distribución TisularRESUMEN
The turnover product of the committed step of menaquinone biosynthesis was isolated and determined to be (1R,2S,5S,6S)-2-succinyl-5-enolpyruvyl-6-hydroxy-3-cyclohexene-1-carboxylate. Structural determination of this key intermediate represents a critical step to complete elucidation of the biosynthetic pathway.
Asunto(s)
Ácidos Ciclohexanocarboxílicos/química , Cetoácidos/química , Vitamina K 2/química , Vitamina K 2/metabolismo , Ácido Corísmico/química , Ácidos Ciclohexanocarboxílicos/síntesis química , Ciclohexenos/química , Cetoácidos/síntesis química , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Estructura Molecular , Protones , EstereoisomerismoRESUMEN
Purpose: CD19, a B-cell lineage-specific marker, is highly represented in B-cell malignancies and an attractive target for therapeutic interventions. MGD011 is a CD19 x CD3 DART bispecific protein designed to redirect T lymphocytes to eliminate CD19-expressing cells. MGD011 has been engineered with a modified human Fc domain for improved pharmacokinetic (PK) properties and designed to cross-react with the corresponding antigens in cynomolgus monkeys. Here, we report on the preclinical activity, safety and PK properties of MGD011.Experimental Design: The activity of MGD011 was evaluated in several in vitro and in vivo models. PK, safety and pharmacodynamic activity was also assessed in dose-escalation and repeat-dose studies of MGD011 administered once weekly in cynomolgus monkeys.Results: MGD011 mediated killing of human B-cell lymphoma lines by human or cynomolgus monkey PBMCs as well as autologous B-cell depletion in PBMCs from both species. MGD011-mediated killing was accompanied by target-dependent T-cell activation and expansion, cytokine release and upregulation of perforin and granzyme B. MGD011 demonstrated antitumor activity against localized and disseminated lymphoma xenografts reconstituted with human PBMCs. In cynomolgus monkeys, MGD011 displayed a terminal half-life of 6.7 days; once weekly intravenous infusion of MGD011 at doses up to 100 µg/kg, the highest dose tested, was well tolerated and resulted in dose-dependent, durable decreases in circulating B cells accompanied by profound reductions of B lymphocytes in lymphoid organs.Conclusions: The preclinical activity, safety and PK profile support clinical investigation of MGD011 as a therapeutic candidate for the treatment of B-cell malignancies. Clin Cancer Res; 23(6); 1506-18. ©2016 AACR.