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1.
Dev Biol ; 493: 1-11, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36265686

RESUMEN

Hedgehog (HH) signaling is a major driver of tissue patterning during embryonic development through the regulation of a multitude of cell behaviors including cell fate specification, proliferation, migration, and survival. HH ligands signal through the canonical receptor PTCH1 and three co-receptors, GAS1, CDON and BOC. While previous studies demonstrated an overlapping and collective requirement for these co-receptors in early HH-dependent processes, the early embryonic lethality of Gas1;Cdon;Boc mutants precluded an assessment of their collective contribution to later HH-dependent signaling events. Specifically, a collective role for these co-receptors during limb development has yet to be explored. Here, we investigate the combined contribution of these co-receptors to digit specification, limb patterning and long bone growth through limb-specific conditional deletion of Cdon in a Gas1;Boc null background. Combined deletion of Gas1, Cdon and Boc in the limb results in digit loss as well as defects in limb outgrowth and long bone patterning. Taken together, these data demonstrate that GAS1, CDON and BOC are collectively required for HH-dependent patterning and growth of the developing limb.


Asunto(s)
Moléculas de Adhesión Celular , Proteínas Hedgehog , Receptores de Superficie Celular , Femenino , Embarazo , Proteínas Portadoras , Moléculas de Adhesión Celular/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas Ligadas a GPI/metabolismo , Proteínas Hedgehog/metabolismo , Receptores de Superficie Celular/metabolismo , Animales
2.
Chemistry ; 30(27): e202304118, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38433408

RESUMEN

New chiral ligands could be obtained by introducing proline moieties and imidazoline moieties to binaphthyl skeletons. The chiral ligands exhibited balanced rigidity and flexibility which could allow the change of the conformations during the reactions on one hand, and could provide sufficient asymmetric induction on the other. The proline moiety could act as a linker connecting the binaphthyl skeletons and the imidazoline moieties as well as a coordinating group for the central metal, and the electronic and steric properties of the imidazoline groups could be carefully fine-tuned by the use of different substituents. In the presence of Cu(II) catalyst bearing such chiral ligands, aza-Friedel-Crafts reaction of 1-naphthols and electron-rich phenols with isatin-derived ketimines provided the desired products with good to excellent yields and up to 99 % ee. The reactions showed good scalability, and excellent ee could still be obtained when the reaction was carried out in gram-scale.

3.
Pharmacol Res ; 202: 107125, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38438091

RESUMEN

G protein-coupled receptors (GPCRs) are currently the most widely focused drug targets in the clinic, exerting their biological functions by binding to chemicals and activating a series of intracellular signaling pathways. Formyl-peptide receptor 1 (FPR1) has a typical seven-transmembrane structure of GPCRs and can be stimulated by a large number of endogenous or exogenous ligands with different chemical properties, the first of which was identified as formyl-methionine-leucyl-phenylalanine (fMLF). Through receptor-ligand interactions, FPR1 is involved in inflammatory response, immune cell recruitment, and cellular signaling regulation in key cell types, including neutrophils, neural stem cells (NSCs), and microglia. This review outlines the critical roles of FPR1 in a variety of heart and brain diseases, including myocardial infarction (MI), ischemia/reperfusion (I/R) injury, neurodegenerative diseases, and neurological tumors, with particular emphasis on the milestones of FPR1 agonists and antagonists. Therefore, an in-depth study of FPR1 contributes to the research of innovative biomarkers, therapeutic targets for heart and brain diseases, and clinical applications.


Asunto(s)
Encefalopatías , Receptores de Formil Péptido , Humanos , N-Formilmetionina Leucil-Fenilalanina/metabolismo , Receptores de Formil Péptido/metabolismo , Encéfalo/metabolismo
4.
Prostaglandins Other Lipid Mediat ; 172: 106833, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38460760

RESUMEN

Smoking causes several diseases such as chronic obstructive pulmonary disease (COPD). Aspirin-triggered-resolvin D1 (AT-RvD1) is a lipid mediator produced during the resolution of inflammation and demonstrates anti-inflammatory and pro-resolution effects in several inflammatory experimental models including in the airways. Here we evaluated the role of AT-RvD1 (100 nM) in bronchial epithelial cells (BEAS-2B) stimulated by cigarette smoke extract (CSE; 1%; 1 cigarette) for 24 h. CSE induced the productions of IL-1ß, TNF-α, IL-10, IL-4 and IFN-γ as well as the activations of NF-κB and STAT3 and the expression of ALX/FPR2 receptor. AT-RvD1 reduced the IL-1ß and TNF-α production and increased the production of IFN-γ. These effects were reversed BOC2, an antagonist of ALX/FPR2 receptor for AT-RvD1. The production of IL-4 and IL-10 were not altered by AT-RvD1. In addition, AT-RvD1 reduced the phosphorylation of NF-κB and STAT3 when compared to CSE-stimulated BEAS-2B cells. No alteration of ALX/FPR2 expression was observed by AT-RvD1 when compared to CSE group. In the human monocytic leukemia cell line, the relative number of copies of IL-1ß and IL-4 was significantly higher in CSE + AT-RvD1 group compared CSE group, however, the expression of M1 cytokine was more pronounced than M2 profile. AT-RvD1 could be an important target for the reduction of inflammation in the airways associated with smoking.


Asunto(s)
Antiinflamatorios , Aspirina , Bronquios , Ácidos Docosahexaenoicos , Células Epiteliales , Humanos , Ácidos Docosahexaenoicos/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Bronquios/efectos de los fármacos , Bronquios/citología , Bronquios/metabolismo , Aspirina/farmacología , Antiinflamatorios/farmacología , FN-kappa B/metabolismo , Factor de Transcripción STAT3/metabolismo , Línea Celular , Humo/efectos adversos , Citocinas/metabolismo , Nicotiana , Receptores de Lipoxina/metabolismo
5.
Macromol Rapid Commun ; : e2400471, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39183584

RESUMEN

Molecularly imprinted silica nanoparticles (SP-MIP) are synthesized for the real-time optical detection of low-molecular-weight compounds. Azo-initiator-modified silica beads are functionalized through reversible addition-fragmentation chain transfer (RAFT) polymerization, which leads to efficient control of the grafted layer. The copolymerization of methacrylic acid (MAA) and ethylene glycol dimethacrylate (EDMA) on azo initiator-coated silica particles (≈100 nm) using chain transfer agent (2-phenylprop-2-yl-dithiobenzoate) is carried out in the presence of a target analyte molecule (l-Boc-phenylalanine anilide, l-BFA). The chemical and morphological properties of SP-MIP are characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, Brunauer-Emmett-Teller surface analysis, and thermogravimetric analysis. Finally, SP-MIP is located on the gold surface to be used as a biorecognition layer on the surface plasmon resonance spectrometer (SPR). The sensitivity, response time, and selectivity of SP-MIP are investigated by three similar analogous molecules (l-Boc-Tryptophan, l-Boc-Tyrosine, and l-Boc-Phenylalanine) and the imprinted particle surface showed excellent relative selectivity toward l-Boc-Phenylalanine (l-BFA) (k = 61), while the sensitivity is recorded as limit of detection = 1.72 × 10-4 m.

6.
Development ; 147(23)2020 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-33060130

RESUMEN

The Hedgehog (HH) pathway controls multiple aspects of craniofacial development. HH ligands signal through the canonical receptor PTCH1, and three co-receptors: GAS1, CDON and BOC. Together, these co-receptors are required during embryogenesis to mediate proper HH signaling. Here, we investigated the individual and combined contributions of GAS1, CDON and BOC to HH-dependent mammalian craniofacial development. Notably, individual deletion of either Gas1 or Cdon results in variable holoprosencephaly phenotypes in mice, even on a congenic background. In contrast, we find that Boc deletion results in facial widening that correlates with increased HH target gene expression. In addition, Boc deletion in a Gas1 null background partially ameliorates the craniofacial defects observed in Gas1 single mutants; a phenotype that persists over developmental time, resulting in significant improvements to a subset of craniofacial structures. This contrasts with HH-dependent phenotypes in other tissues that significantly worsen following combined deletion of Gas1 and Boc Together, these data indicate that BOC acts as a multi-functional regulator of HH signaling during craniofacial development, alternately promoting or restraining HH pathway activity in a tissue-specific fashion.


Asunto(s)
Moléculas de Adhesión Celular/genética , Proteínas de Ciclo Celular/genética , Desarrollo Embrionario/genética , Inmunoglobulina G/genética , Receptores de Superficie Celular/genética , Animales , Anomalías Craneofaciales/genética , Anomalías Craneofaciales/patología , Proteínas Ligadas a GPI/genética , Eliminación de Gen , Proteínas Hedgehog/genética , Holoprosencefalia/genética , Holoprosencefalia/patología , Humanos , Ratones , Receptor Patched-1/genética , Transducción de Señal/genética
7.
Bioorg Med Chem Lett ; 90: 129346, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37217024

RESUMEN

We present a general efficient green method for the preparation of nitro N,N'-diaryl thioureas via a one-pot method using cyrene as a solvent with almost quantitative yields. This confirmed the viability of cyrene as a green alternative to THF in the synthesis of thiourea derivatives. After screening different reducing conditions, the nitro N,N'-diaryl thioureas were selectively reduced using Zn dust in the presence of water and acid to the corresponding amino N,N'-diaryl thioureas. These were then used to test the installation of the Boc-protected guanidine group with N,N'-bis-Boc protected pyrazole-1-carboxamidine as a guanidylating reagent not requiring mercury(II) activation. Finally, the TFA salts obtained after Boc-deprotection of two sample compounds were tested for their affinity towards DNA showing no binding.


Asunto(s)
Guanidinas , Tiourea , Guanidina , Tiourea/química
8.
Molecules ; 28(3)2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36770988

RESUMEN

The photosynthetic tetrapyrroles share a common structural feature comprised of a ß-ketoester motif embedded in an exocyclic ring (ring E). As part of a total synthesis program aimed at preparing native structures and analogues, 3-(3-methoxy-1,3-dioxopropyl)pyrrole was sought. The pyrrole is a precursor to analogues of ring C and the external framework of ring E. Four routes were developed. Routes 1-3 entail a Pd-mediated coupling process of a 3-iodopyrrole with potassium methyl malonate, whereas route 4 relies on electrophilic substitution of TIPS-pyrrole with methyl malonyl chloride. Together, the four routes afford considerable latitude. A long-term objective is to gain the capacity to create chlorophylls and bacteriochlorophylls and analogues thereof by facile de novo means for diverse studies across the photosynthetic sciences.


Asunto(s)
Pirroles , Tetrapirroles , Pirroles/química , Clorofila/química , Bacterioclorofilas/química , Fotosíntesis
9.
Angew Chem Int Ed Engl ; 62(1): e202214053, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36344442

RESUMEN

Chemical synthesis of proteins bearing base-labile post-translational modifications (PTMs) is a challenging task. For instance, O-acetylation and S-palmitoylation PTMs cannot survive Fmoc removal conditions during Fmoc-solid phase peptide synthesis (SPPS). In this work, we developed a new Boc-SPPS-based strategy for the synthesis of peptide C-terminal salicylaldehyde (SAL) esters, which are the key reaction partner in Ser/Thr ligation and Cys/Pen ligation. The strategy utilized the semicarbazone-modified aminomethyl (AM) resin, which could support the Boc-SPPS and release the peptide SAL ester upon treatment with TFA/H2 O and pyruvic acid. The non-oxidative aldehyde regeneration was fully compatible with all the canonical amino acids. Armed with this strategy, we finished the syntheses of the O-acetylated protein histone H3(S10ac, T22ac) and the hydrophobic S-palmitoylated peptide derived from caveolin-1.


Asunto(s)
Péptidos , Proteínas , Péptidos/química , Aldehídos , Ésteres/química
10.
Mar Drugs ; 20(4)2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35447911

RESUMEN

Cancer stem cells (CSCs) drive aggressiveness and metastasis by utilizing stem cell-related signals. In this study, 5-O-(N-Boc-l-alanine)-renieramycin T (OBA-RT) was demonstrated to suppress CSC signals and induce apoptosis. OBA-RT exerted cytotoxic effects with a half-maximal inhibitory concentration of approximately 7 µM and mediated apoptosis as detected by annexin V/propidium iodide using flow cytometry and nuclear staining assays. Mechanistically, OBA-RT exerted dual roles, activating p53-dependent apoptosis and concomitantly suppressing CSC signals. A p53-dependent pathway was indicated by the induction of p53 and the depletion of anti-apoptotic Myeloid leukemia 1 (Mcl-1) and B-cell lymphoma 2 (Bcl-2) proteins. Cleaved poly (ADP-ribose) polymerase (Cleaved-PARP) was detected in OBA-RT-treated cells. Interestingly, OBA-RT exerted strong CSC-suppressing activity, reducing the ability to form tumor spheroids. In addition, OBA-RT could induce apoptosis in CSC-rich populations and tumor spheroid collapse. CSC markers, including prominin-1 (CD133), Octamer-binding transcription factor 4 (Oct4), and Nanog Homeobox (Nanog), were notably decreased after OBA-RT treatment. Upstream CSCs regulating active Akt and c-Myc were significantly decreased; indicating that Akt may be a potential target of action. Computational molecular modeling revealed a high-affinity interaction between OBA-RT and an Akt molecule. This study has revealed a novel CSC inhibitory effect of OBA-RT via Akt inhibition, which may improve cancer therapy.


Asunto(s)
Neoplasias Pulmonares , Proteínas Proto-Oncogénicas c-akt , Alanina/farmacología , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Humanos , Neoplasias Pulmonares/patología , Células Madre Neoplásicas , Proteínas Proto-Oncogénicas c-akt/metabolismo , Tetrahidroisoquinolinas , Proteína p53 Supresora de Tumor/metabolismo
11.
J Labelled Comp Radiopharm ; 65(8): 206-222, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35466460

RESUMEN

Pharmaceutical grade 3'-deoxy-3'-[18 F]fluorothymidine [18 F]FLT was synthesized using 3-N-Boc-5'-O-dimethoxytrityl-3'-O-nosyl-thymidine (BOC-Nosyl) precursor, in the general purpose TRACERlab FX modules. Purification of [18 F]FLT, via solid phase extraction (SPE) after radiosynthesis, using a combination of different SPE cartridges, yielded satisfactory results, with radiochemical and chemical purity >99%. While the non-decay corrected radiochemical yield (RCY) with 20 mg (24 µmole) of BOC-Nosyl precursor was found to be 6.80 ± 0.16%, the decay corrected radiochemical yield (RCY) was 9.95 ± 0.24%. Residual acetone, acetonitrile, and ethanol levels were found to be 22.97 ± 0.76, 109.08 ± 0.93, and 7,666.45 ± 3.7 ppm, respectively. A simplified method for solid-phase purification of [18 F]FLT was developed, circumventing the need for HPLC purification. Biodistribution in C57BL/6 mice with B16F10 cell line-induced melanoma showed tumor to blood ratio of ~3.8 at 90 min. PET/CT imaging of normal rabbit injected with [18 F]FLT shows selective uptake in the bone marrow and small intestine. [18 F]FLT was found to be excreted through the kidneys and get collected in the urinary bladder, 120 min post injection. PET/CT imaging performed in rabbit model at 30, 60, 90, and 120 min post [18 F]FLT injections showed concordance with tissue distribution kinetics of mice tumor model.


Asunto(s)
Didesoxinucleósidos , Neoplasias , Animales , Inmunoglobulina G , Ratones , Ratones Endogámicos C57BL , Preparaciones Farmacéuticas , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones , Conejos , Radiofármacos , Receptores de Superficie Celular , Timidina , Distribución Tisular
12.
Pharmacol Res ; 169: 105658, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33992797

RESUMEN

Pancreatic cancer is one of the most aggressive cancers with a poor prognosis and 5-year low survival rate. In the present study, we report that bruceine A, a quassinoid found in Brucea javanica (L.) Merr. has a strong antitumor activity against human pancreatic cancer cells both in vitro and in vivo. Human proteome microarray reveals that 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 4 (PFKFB4) is the candidate target of bruceine A and both fluorescence measurement and microscale thermophoresis suggest bruceine A binds to PFKFB4. Bruceine A suppresses glycolysis by inhibiting PFKFB4, leading to cell cycle arrest and apoptosis in MIA PaCa-2 cells. Furthermore, glycogen synthase kinase-3 ß (GSK3ß) is identified as a downstream target of PFKFB4 and an PFKFB4-interacting protein. Moreover, bruceine A induces cell growth inhibition and apoptosis through GSK3ß, which is dysregulated in pancreatic cancer and closely related to the prognosis. In all, these findings suggest that bruceine A inhibits human pancreatic cancer cell growth via PFKFB4/GSK3ß-mediated glycolysis, and it may serve as a potent agent for curing human pancreatic cancer.


Asunto(s)
Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Neoplasias Pancreáticas/tratamiento farmacológico , Fosfofructoquinasa-2/metabolismo , Cuassinas/uso terapéutico , Transducción de Señal/efectos de los fármacos , Animales , Antineoplásicos/farmacología , Western Blotting , Línea Celular Tumoral , Humanos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Microscopía Fluorescente , Trasplante de Neoplasias , Neoplasias Pancreáticas/metabolismo , Reacción en Cadena de la Polimerasa , Cuassinas/farmacología
13.
Bioorg Med Chem ; 42: 116234, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34098191

RESUMEN

We described a mode of catalytic activation that accomplished the α-alkylation of N-Boc saturated heterocycles with DNA-linked acrylamide via photoredox-mediated hydrogen atom transfer (HAT) catalysis. This C(sp3)-C(sp3) bond formation reaction tolerated five-, six- and seven-membered cyclic substrates, substantially streamline synthetic efforts to functionalize the α-position of heterocycles with native CH functional handle. This photoredox catalyzed CH functionalization proceeded in mild DNA-compatible condition, and suited for the construction of DNA-encoded libraries.


Asunto(s)
ADN/química , Hidrógeno/química , Acrilamida/química , Catálisis , Estructura Molecular , Oxidación-Reducción , Procesos Fotoquímicos
14.
Pharmacology ; 106(5-6): 305-315, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33756489

RESUMEN

BACKGROUND: Piperidines are biogenic amines studied mainly in toxicology because they were initially found as alkaloids from peppers and insect venoms. Piperidines are also produced in the human body, and their actions seem to be related to wakefulness/sleep and other cognitive phenomena. Piperidines have been minimally characterized for therapeutic applications. In this context, 1-Boc-piperidine-4-carboxaldehyde (1-Boc-piperidine) is a piperidine-derivative molecule with no mechanism of action reported, although its uses include the synthesis of GPR119 selective agonists that have been patented as anti-obesity drugs. OBJECTIVES: The aim of this work was to study the effects of 1-Boc-piperidine on binge-eating behaviour and anxiety in Wistar rats. METHODS: In experimental protocol 1, binge-eating behaviour was induced in animals that received pre-treatment (i.p.) with (i) vehicle (methanol 10%; 1 mL/kg), (ii) 1-Boc-piperidine (1 µmol kg-1), or (iii) 1-Boc-piperidine (10 µmol kg-1). In experimental protocol 2, mildly stressed animals were evaluated in the elevated plus maze under the acute effects of the pre-treatments applied in experimental protocol 1. RESULTS AND CONCLUSIONS: 1-Boc-piperidine decreased, in a dose-dependent manner, the intake of calories from a succulent hyper-caloric food in a binge-eating protocol in female rats, whereas the acute exposition to this piperidine exerted an anxiolytic effect in the male rat. In both effects, the mechanism of action remains to be characterized.


Asunto(s)
Ansiedad/tratamiento farmacológico , Trastorno por Atracón/tratamiento farmacológico , Animales , Ansiedad/etiología , Conducta Animal/efectos de los fármacos , Trastorno por Atracón/etiología , Relación Dosis-Respuesta a Droga , Ingestión de Energía/efectos de los fármacos , Conducta Alimentaria/efectos de los fármacos , Inyecciones Intraperitoneales , Ligandos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Dolor/complicaciones , Unión Proteica , Ratas Wistar , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Serotonina/química , Receptores de Serotonina/metabolismo , Estrés Psicológico/complicaciones , Aumento de Peso/efectos de los fármacos
15.
Sensors (Basel) ; 21(6)2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33799727

RESUMEN

Binary offset carrier (BOC) modulation is a new modulation method that has been gradually applied to the Global Satellite Navigation System (GNSS) in recent years. However, due to the multi-peaks in its auto-correlation function (ACF), it will incur a false lock and generate synchronization ambiguous potentially. In this paper, an unambiguous synchronization method based on a reconstructed correlation function is proposed to solve the ambiguity problem. First, through the shape code vector constructed in this paper, the general cross-correlation function (CCF) expression of the BOC modulated signal will be obtained. Based on the features of the signal correlation function, it is decomposed into a matrix form of trigonometric functions. Then, it generates two local signal waves using a specific method, then the proposed method is implemented to obtain a no-side-peak correlation function by reconstructing the cross-correlation between the received signal and the two local signals. Simulations showed that it fully eliminates the side-peak threat and significantly removes the ambiguity during the synchronization of the BOC signals. This paper also gives the improved structure of acquisition and tracking. The detailed theoretical deduction of detection probability and code tracking error is demonstrated, and the corresponding phase discrimination function is given. In terms of de-blurring ability and detection probability performance, the proposed method outperformed other conventional approaches. The tracking performance was superior to the comparison methods and the phase discrimination curve only had a zero-crossing, which successfully removed the false lock points. In addition, in multipath mitigation, it outperformed the ACF of the BOC signal, and performs as well as the autocorrelation side-peak cancellation technique (ASPeCT) for BOC(kn,n) signals.

16.
Angiogenesis ; 23(3): 357-369, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32152757

RESUMEN

N-formyl peptide receptors (FPRs) are G protein-coupled receptors involved in the recruitment and activation of immune cells in response to pathogen-associated molecular patterns. Three FPRs have been identified in humans (FPR1-FPR3), characterized by different ligand properties, biological function and cellular distribution. Recent findings from our laboratory have shown that the peptide BOC-FLFLF (L-BOC2), related to the FPR antagonist BOC2, acts as an angiogenesis inhibitor by binding to various angiogenic growth factors, including vascular endothelial growth factor-A165 (VEGF). Here we show that the all-D-enantiomer of L-BOC2 (D-BOC2) is devoid of any VEGF antagonist activity. At variance, D-BOC2, as well as the D-FLFLF and succinimidyl (Succ)-D-FLFLF (D-Succ-F3) D-peptide variants, is endowed with a pro-angiogenic potential. In particular, the D-peptide D-Succ-F3 exerts a pro-angiogenic activity in a variety of in vitro assays on human umbilical vein endothelial cells (HUVECs) and in ex vivo and in vivo assays in chick and zebrafish embryos and adult mice. This activity is related to the capacity of D-Succ-F3 to bind FRP3 expressed by HUVECs. Indeed, the effects exerted by D-Succ-F3 on HUVECs are fully suppressed by the G protein-coupled receptor inhibitor pertussis toxin, the FPR2/FPR3 antagonist WRW4 and by an anti-FPR3 antibody. A similar inhibition was observed following WRW4-induced FPR3 desensitization in HUVECs. Finally, D-Succ-F3 prevented the binding of the anti-FPR3 antibody to the cell surface of HUVECs. In conclusion, our data demonstrate that the angiogenic activity of D-Succ-F3 is due to the engagement and activation of FPR3 expressed by endothelial cells, thus shedding a new light on the biological function of this chemoattractant receptor.


Asunto(s)
Células Endoteliales de la Vena Umbilical Humana/metabolismo , Neovascularización Fisiológica/efectos de los fármacos , Oligopéptidos/farmacología , Receptores de Formil Péptido , Humanos , Oligopéptidos/síntesis química , Oligopéptidos/química , Receptores de Formil Péptido/agonistas , Receptores de Formil Péptido/metabolismo
17.
J Pept Sci ; 26(6): e3251, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32249520

RESUMEN

During the final step of t-Boc/Bzl, solid-phase peptide synthesis (SPPS)-protecting groups from amino acids (aa) side chains must be removed from the target peptides during cleavage from the solid support. These reaction steps involve hydrolysis with hydrogen fluoride (HF) in the presence of a nucleophile (scavenger), whose function is to trap the carbocations produced during SN 1-type reactions. Five peptide sequences were synthesised for evaluating p-methoxyphenol effectiveness as a potent scavenger. After the synthesis, the resin-peptide was then separated into two equal parts to be cleaved using two scavengers: conventional reactive p-cresol (reported in the literature as an effective acyl ion eliminator) and p-methoxyphenol (hypothesised as fulfilling the same functions as the routinely used scavenger). Detailed analysis of the electrostatic potential map (EPM) revealed similarities between these two nucleophiles, regarding net atomic charge, electron density distribution, and similar pKa values. Good scavenger efficacy was observed by chromatography and mass spectrometry results for the synthesised molecules, which revealed that p-methoxyphenol can be used as a potent scavenger during SPPS by t-Boc/Bzl strategy, as similar results were obtained using the conventional scavenger.


Asunto(s)
Anisoles/química , Péptidos/síntesis química , Técnicas de Síntesis en Fase Sólida , Estructura Molecular , Péptidos/química
18.
Sensors (Basel) ; 20(2)2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31952201

RESUMEN

The autocorrelation function (ACF) of the Binary Offset Carrier modulation (BOC) signal for Global Navigation Satellite System (GNSS) has multiple peaks, ambiguity is easily generated during the synchronization of the baseband signal. Some methods have been proposed to remove the ambiguity, but the performance is not suitable for high-order BOC signals or does not maintain narrow correlation characteristics. This paper proposes a sub-function reconstruction synchronization algorithm to solve this problem, of which the key is to design a new local auxiliary code: the local Pseudo-Random Noise (PRN) code is divided into several new codes with different delays. The auxiliary code performs a coherent integration operation with the received signal. Then, a correlation function without any positive side peaks is obtained by multiplying the two correlation results to make the acquisition/tracking completely unambiguous. The paper gives a design scheme of navigation signal acquisition/tracking and deduces the theoretical analysis of detection performance. The phase discrimination function is provided. The performance of the method is analyzed from both theoretical and simulation aspects. Compared with the Binary phase shift keying-like (BPSK-LIKE) method, Subcarrier Phase Cancellation (SCPC) method and the Autocorrelation Side-Peak Cancellation Technique (ASPeCT) method, the proposed method has the best detection probability for the acquisition, which is 0.5 dB-Hz better than ASPeCT. For tracking, the proposed method performs best in terms of phase-detection curve, anti-multipath performance, and anti-noise performance. For high-order BOC signals, the SRSA technique successfully removes the false lock points, and there is only one multipath error envelope, and the code tracking error is almost the same as the ASPeCT method.

19.
Sensors (Basel) ; 20(12)2020 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-32630365

RESUMEN

Global Navigation Satellite Systems (GNSS) are the main source of position, navigation, and timing (PNT) information and will be a key player in the next-generation intelligent transportation systems and safety-critical applications, but several limitations need to be overcome to meet the stringent performance requirements. One of the open issues is how to provide precise PNT solutions in harsh propagation environments. Under nominal conditions, the former is typically achieved by exploiting carrier phase information through precise positioning techniques, but these methods are very sensitive to the quality of phase observables. Another option that is gaining interest in the scientific community is the use of large bandwidth signals, which allow obtaining a better baseband resolution, and therefore more precise code-based observables. Two options may be considered: (i) high-order binary offset carrier (HO-BOC) modulations or (ii) the concept of GNSS meta-signals. In this contribution, we assess the time-delay and phase maximum likelihood (ML) estimation performance limits of such signals, together with the performance translation into the position domain, considering single point positioning (SPP) and RTK solutions, being an important missing point in the literature. A comprehensive discussion is provided on the estimators' behavior, the corresponding ML threshold regions, the impact of good and bad satellite constellation geometries, and final conclusions on the best candidates, which may lead to precise solutions under harsh conditions. It is found that if the receiver is constrained by the receiver bandwidth, the best choices are the L1-M or E6-Public Regulated Service (PRS) signals. If the receiver is able to operate at 60 MHz, it is recommended to exploit the full-bandwidth Galileo E5 signal. In terms of robustness and performance, if the receiver can operate at 135 MHz, the best choice is to use the GNSS meta-signals E5 + E6 or B2 + B3, which provide the best overall performances regardless of the positioning method used, the satellite constellation geometry, or the propagation conditions.

20.
Biochem Biophys Res Commun ; 512(1): 49-52, 2019 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-30857637

RESUMEN

Lipoblastoma is a rare benign adipose tissue tumor that occurs mostly in infants and children. Histological diagnosis of lipoblastoma is sometimes difficult because it closely resembles other lipomatous tumors. The detection of PLAG1 gene rearrangement is useful for the diagnosis of lipoblastoma. Four PLAG1 fusion partner genes are known in lipoblastoma: HAS2 at 8q24.1, COL1A2 at 7q22, COL3A1 at 2q32, and RAB2A at 8q12. Herein, we describe a novel fusion gene in a case of lipoblastoma of left back origin. We identified a potential PLAG1 fusion partner using 5' rapid amplification of cDNA ends, and sequence analysis revealed the novel fusion gene, BOC-PLAG1. The BOC-PLAG1 fusion transcript consists of the first exon of the BOC gene fused to exon 2 or exon 3 of the PLAG1 gene. PLAG1 expression was found to be 35.7 ±â€¯2.1 times higher in the tumor specimen than in human adipocytes by qRT-PCR. As a result of the translocation, the constitutively active promoter of BOC leads to PLAG1 overexpression. The identification of the BOC-PLAG1 fusion gene will lead to more accurate diagnosis of lipoblastoma.


Asunto(s)
Proteínas de Unión al ADN/genética , Inmunoglobulina G/genética , Lipoblastoma/genética , Fusión de Oncogenes , Receptores de Superficie Celular/genética , Adipocitos/metabolismo , Dorso , Secuencia de Bases , Niño , ADN de Neoplasias/genética , Femenino , Expresión Génica , Humanos , Lipoblastoma/diagnóstico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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