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1.
Bioorg Med Chem Lett ; 99: 129623, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38242331

RESUMO

Dengue virus (DENV) is a significant global health threat, causing millions of cases worldwide each year. Developing antiviral drugs for DENV has been a challenging endeavor. Our previous study identified anti-DENV properties of two (-)-cytisine derivatives contained substitutions within the 2-pyridone core from a pool of 19 (-)-cytisine derivatives. This study aimed to expand on the previous research by investigating the antiviral potential of N-methylcytisine thio (mCy thio) derivatives against DENV, understanding the molecular mechanisms of antiviral activity for the active thio derivatives. The inhibitory assays on DENV-2-induced cytopathic effect and infectivity revealed that mCy thio derivatives 3 ((1R,5S)-3-methyl-1,2,3,4,5,6-hexahydro-8H-1,5-methanopyrido[1,2-a][1,5]diazocine-8-thione) and 6 ((1S,5R)-3-methyl-2-thioxo-1,2,3,4,5,6-hexahydro-8H-1,5-methanopyrido[1,2-a][1,5]diazocin-8-one) were identified as the active compounds against both DENV-1 and DENV-2. Derivative 6 displayed robust antiviral activity against DENV-2, with EC50 values ranging from 0.002 to 0.005 µM in different cell lines. Derivative 3 also exhibited significant antiviral activity against DENV-2. The study found that these compounds are effective at inhibiting DENV-2 at both the entry stage (including virus attachment) and post-entry stages of the viral life cycle. The study also investigated the inhibition of the DENV-2 NS2B-NS3 protease activity by these compounds. Derivative 6 demonstrated notably stronger inhibition compared to mCy thio 3, revealing its dual antiviral action at both the entry and post-entry stages. Molecular docking simulations indicated that mCy thio derivatives 3 and 6 bind to the domain I and III of the DENV E protein, as well as the active of NS2B-NS3 protease, suggesting their molecular interactions with the virus. The study demonstrates the antiviral efficacy of N-methylcytisine thio derivatives against DENV. It provides valuable insights into the potential interactions between these compounds and viral target proteins, which could be useful in the development of antiviral drugs for DENV.


Assuntos
Vírus da Dengue , Alcaloides Quinolidizínicos , Simulação de Acoplamento Molecular , Proteínas do Envelope Viral , Peptídeo Hidrolases , Serina Endopeptidases/metabolismo , Antivirais/farmacologia , Antivirais/metabolismo , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais
2.
J Phys Chem A ; 126(42): 7787-7793, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36240026

RESUMO

Two-photon entangled generation is used to produce an entangled photon source which is a key and core element concerning the technology applications of quantum computing, quantum communication, and quantum precision measurement. In this work, we have deduced the formulas of dynamic susceptibility and phase-matching angle of two-photon entangled generation in nonlinear optical crystals. The formulas are employed to compute the susceptibilities and phase-matching angles of these optical processes for uniaxial and biaxial crystals. The susceptibility magnitude and phase-matching condition of two-photon entangled generation affect the performance of the source. The calculated results by these formulas are employed to study properties and estimate the performance of an entangled photon source. In this way, we discuss the phase matching among waves and working wavelength in an entangled source that affects the efficiency of satellite communication with the ground during the day and night.

3.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36142222

RESUMO

Dengue virus (DENV) is one of the most geographically distributed mosquito-borne flaviviruses, like Japanese encephalitis virus (JEV), and Zika virus (ZIKV). In this study, a library of the known and novel Glycyrrhizic acid (GL) derivatives bearing amino acid residues or their methyl/ethyl esters in the carbohydrate part were synthesized and studied as DENV inhibitors in vitro using the cytopathic effect (CPE), viral infectivity and virus yield assays with DENV1 and DENV-2 in Vero E6 and A549 cells. Among the GL conjugates tested, compound hits GL-D-ValOMe 3, GL-TyrOMe 6, GL-PheOEt 11, and GL-LysOMe 21 were discovered to have better antiviral activity than GL, with IC50 values ranging from <0.1 to 5.98 µM on the in vitro infectivity of DENV1 and DENV2 in Vero E6 and A549 cells. Compound hits 3, 6, 11, and 21 had a concentration-dependent inhibition on the virus yield in Vero E6, in which GL-D-ValOMe 3 and GL-PheOEt 11 were the most active inhibitors of DENV2 yield. Meanwhile, the time-of-addition assay indicated that conjugates GL-D-ValOMe 3 and GL-PheOEt 11 exhibited a substantial decrease in the DENV2 attachment stage. Subsequently, chimeric single-round infectious particles (SRIPs) of DENV2 C-prM-E protein/JEV replicon and DENV2 prM-E/ZIKV replicon were utilized for the DENV envelope I protein-mediated attachment assay. GL conjugates 3 and 11 significantly reduced the attachment of chimeric DENV2 C-prM-E/JEV and DENV2 prM-E/ZIKV SRIPs onto Vero E6 cells in a concentration-dependent manner but did not impede the attachment of wild-type JEV CprME/JEV and ZIKV prM-E/ZIKV SRIPs, indicating the inhibition of Compounds 3 and 11 on DENV2 E-mediated attachment. Molecular docking data revealed that Compounds 3 and 11 have hydrophobic interactions within a hydrophobic pocket among the interfaces of Domains I, II, and the stem region of the DENV2 envelope (E) protein. These results displayed that Compounds 3 and 11 were the lead compounds targeting the DENV E protein. Altogether, our findings provide new insights into the structure−activity relationship of GL derivatives conjugated with amino acid residues and can be the new fundamental basis for the search and development of novel flavivirus inhibitors based on natural compounds.


Assuntos
Vírus da Dengue , Dengue , Vírus da Encefalite Japonesa (Espécie) , Vírus da Encefalite Japonesa (Subgrupo) , Flavivirus , Infecção por Zika virus , Zika virus , Aminoácidos/metabolismo , Animais , Antivirais/metabolismo , Antivirais/farmacologia , Carboidratos , Dengue/tratamento farmacológico , Ácido Glicirrízico/metabolismo , Ácido Glicirrízico/farmacologia , Humanos , Simulação de Acoplamento Molecular
4.
Viruses ; 14(7)2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35891552

RESUMO

Zika virus (ZIKV) is a positive-sense single-stranded RNA virus in the Flaviviridae, which is classified into two different lineages Asian and African. The outbreak of ZIKV Asian lineage isolates in 2015-2016 is associated with the increase in cases with prenatal microcephaly and Guillain-Barré syndrome, and has sparked attention throughout the world. Genome sequence alignment and the analysis of Asian and African lineage isolates indicate that amino acid changes, particular in positively charged amino acid substitutions in the pr region of prM protein might involve a phenotypic change that links with the global outbreak of ZIKV Asian-lineage. The study generated and characterized the virological properties of wild type and mutants of single-round infectious particles (SRIPs) and infectious clones (i.c.s) of ZIKV Asian-lineage Natal RGN strain, and then identified the function of amino acid substitutions at the positions 139 [Asn139→Ser139 (N139S)] and 143 [Glu143→Lys143 (E143K)] in ZIKV polyproteins (located within the pr region of prM protein) in the infectivity and cytopathogenicity. The E143K SRIP and i.c. of Natal RGN strain exhibited relatively higher levels of cytopathic effect, EGFP reporter, viral RNA and protein synthesis, and virus yield in three types of human cell lines, TE617, SF268 and HMC3, compared to wild type (WT), N139S SRIPs and i.c.s, which displayed more efficiency in replication kinetics. Additionally, E143K Natal RGN i.c. had greater activities of virus attachment and entry, yielded higher titers of intracellular and extracellular virions, and assembled the E proteins near to the plasma membrane in infected cells than the other i.c.s. The results indicate that the positively charged amino acid residue Lys143, a conserved residue in the pr region of prM of ZIKV African lineages, plays a crucial role in viral replication kinetics, including viral attachment, entry, assembly and egress. Thus, the negatively charged amino acid residue Glu143 within the pr region of prM leads to an alteration of the phenotypes, in particular, a lower replication efficiency of ZIKV Asian-lineage isolates with the attenuation of infectivity and cytopathicity.


Assuntos
Proteínas do Envelope Viral , Infecção por Zika virus , Zika virus , Aminoácidos/genética , Feminino , Humanos , Mutação , Gravidez , Proteínas do Envelope Viral/genética , Replicação Viral , Zika virus/patogenicidade
5.
Infect Chemother ; 53(4): 730-740, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34951532

RESUMO

INTRODUCTION: Zika virus (ZIKV), a mosquito-borne flavivirus, causes the outbreaks of Latin America in 2015 - 2016, with the incidence of neurological complications. Sunitinib malate, an orally bioavailable malate salt of the tyrosine kinase inhibitor, is suggested as a broad-spectrum antiviral agent against emerging viruses like severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2. MATERIALS AND METHODS: This study investigated the antiviral efficacy and antiviral mechanisms of sunitinib malate against ZIKV infection using cytopathic effect reduction, virus yield, and time-of-addition assays. RESULTS: Sunitinib malate concentration-dependently reduced ZIKV-induced cytopathic effect, the expression of viral proteins, and ZIKV yield in supernatant with 50% inhibitory concentration (IC50) value of 0.015 µM, and the selectivity index of greater than 100 against ZIKV infection, respectively. Sunitinib malate had multiple antiviral actions during entry and post-entry stages of ZIKV replication. Sunitinib malate treatment at entry stage significantly reduced the levels of ZIKV RNA replication with the reduction of (+) RNA to (-) RNA ratio and the production of new intracellular infectious particles in infected cells. The treatment at post-entry stage caused a concentration-dependent increase in the levels of ZIKV (+) RNA and (-) RNA in infected cells, along with enlarging the ratio of (+) RNA to (-) RNA, but caused a pointed increase in the titer of intracellular infectious particles by 0.01 and 0.1 µM, and a substantial decrease in the titer of intracellular infectious particles by 1 µM. CONCLUSION: The study discovered the antiviral actions of sunitinib malate against ZIKV infection, demonstrating a repurposed, host-targeted approach to identify potential antiviral drugs for treating emerging and global viral diseases.

6.
Inorg Chem ; 60(20): 15593-15598, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34590833

RESUMO

The quaternary selenide Ba4GeSb2Se11 was prepared by a high-temperature solid state reaction method. Ba4GeSb2Se11 crystallizes in an acentric orthorhombic space group Cmc21 with the lattice constants a = 9.370(11) Å, b = 25.850(0) Å, and c = 8.798(10) Å. The compound is composed of a [SbSe3]3- trigonal pyramid, [GeSbSe5]3- dimers, V-shaped Se32-, and the adjacent Ba2+ ions. It has indirect band gap of 1.35 eV and exhibits a second harmonic generation intensity of about 0.2 times that of the benchmark compound AgGaS2 at the same particle size. Interestingly, theoretical analyses show that the central Se atom of Se32- has the largest contribution (8.1%) to d31 compared to that of other Se atoms, which may be due to its easy swing in the a-axis direction.

7.
Oncol Lett ; 19(3): 2397-2403, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32194739

RESUMO

Furoquinolone and its derivatives exhibit antimicrobial, anti-allergic, anti-inflammatory and anticancer properties. The present study investigated the anti-tumor activity of synthesized intermediates of furoquinolone in human promyelocytic leukemia HL-60 cells. The biological effects of the active compound ethyl 2-anilino-4-oxo-4,5-dihydrofuran-3-carboxylate (compound 131) were examined in HL-60 cells. The following properties were analyzed: Cell survival, cell cycle profile, caspase-3 activity, Bax and Bcl-2 expression, the amount of intracellular Ca2+, the number of reactive oxygen species (ROS) and the mitochondrial membrane potential. Compound 131 (50% cytotoxic concentration, 23.5 µM) significantly reduced the proliferation of HL-60 cells and was revealed to induce apoptosis in HL-60 cells in a concentration-dependent manner. Moreover, this was associated with the activation of caspase-3, upregulation of Bax, an increase in intracellular Ca2+ and ROS production, and a decrease in mitochondrial membrane potential and Bcl-2 expression levels. Compound 131, a novel 4,5-dihydrofuran-3-carboxylate, induced apoptosis in HL-60 cells via the increase of intracellular Ca2+ and ROS to alter the mitochondrial membrane potential and the protein level of Bax and Bcl-2, as well as activating caspase-3. The results of the current study indicate that compound 131 may represent a promising compound for the development of anti-leukemia therapeutics.

8.
Viruses ; 11(11)2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683628

RESUMO

Zika virus (ZIKV) is transmitted by Aedes mosquitoes and exhibits genetic variation with African and Asian lineages. ZIKV Natal RGN strain, an Asian-lineage virus, has been identified in brain tissues from fetal autopsy cases with microcephaly and is suggested to be a neurotropic variant. However, ZIKV Natal RGN strain has not been isolated; its biological features are not yet illustrated. This study rescued and characterized recombinant, single-round infectious particles (SRIPs) of the ZIKV Natal RGN strain using reverse genetic and synthetic biology techniques. The DNA-launched replicon of ZIKV Natal RGN was constructed and contains the EGFP reporter, lacks prM-E genes, and replicates under CMV promoter control. The peak in the ZIKV Natal RGN SRIP titer reached 6.25 × 106 TCID50/mL in the supernatant of prM-E-expressing packaging cells 72 h post-transfection with a ZIKV Natal RGN replicon. The infectivity of ZIKV Natal RGN SRIPs has been demonstrated to correlate with the green florescence intensity of the EGFP reporter, the SRIP-induced cytopathic effect, and ZIKV's non-structural protein expression. Moreover, ZIKV Natal RGN SRIPs effectively self-replicated in rhabdomyosarcoma/muscle, glioblastoma/astrocytoma, and retinal pigmented epithelial cells, displaying unique cell susceptibility with differential attachment activity. Therefore, the recombinant ZIKV Natal RGN strain was rescued as SRIPs that could be used to elucidate the biological features of a neurotropic strain regarding cell tropism and pathogenic components, apply for antiviral agent screening, and develop vaccine candidates.


Assuntos
Replicação Viral , Zika virus/genética , Linhagem Celular , DNA Recombinante , Genes Reporter/genética , Humanos , Microcefalia/virologia , Replicon/genética , Genética Reversa , Biologia Sintética , Carga Viral , Proteínas não Estruturais Virais/metabolismo , Montagem de Vírus , Zika virus/patogenicidade , Infecção por Zika virus/virologia
9.
Bioorg Med Chem Lett ; 29(23): 126742, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648857

RESUMO

Japanese encephalitis virus (JEV), a mosquito-borne flavivirus, occasionally causes severe central nervous system disorders in the risk zone where more than 3 billion people reside. Our prior studies demonstrated antiviral potential of 4,5-dihydrofuran-3-carboxylate compound CW-33 (ethyl 2-(3',5'-dimethylanilino)-4-oxo-4,5-dihydrofuran-3-carboxylate) and its derivative CW-33A ((ethyl 2-(2-fluoroanilino)-4-oxo-4,5-dihydrofuran-3-carboxylate) against JEV infection ((Int. J. Mol. Sci. 2016, 17: E1386; Sci. Rep. 2018, 8: 16595). This study synthesized six new CW-33 derivatives containing chloro, or bromo groups at the C-2, C-3, or C-4 of anilino ring of CW-33, and assessed the antiviral activity and mechanisms of these chloro- and bromo-anilino substitutedderivatives. CW-33K, CW-33L and CW-33M had the bromo-substituents at the C-2, C-3, or C-4 of anilino ring of CW-33, respectively, showing the higher anti-JEV activity than CW-33 and other derivatives. CW-33K (ethyl 2-(2-bromoanilino)-4-oxo-4,5-dihydrofuran-3-carboxylate) exhibited the highest antiviral efficacy and therapeutic index. The IC50 value of CW-33K was less than 5 µM for reducing JEV-induced cytopathic effect, virus infectivity and virus yield. CW-33K significantly inhibited the JEV replication at the early and late stages, suppressing viral RNA synthesis and intracellular JEV particle production. The study demonstrated that the CW-33 derivative with a bromosubstitutionat the C-2 anilino ring improved the antiviral activity JEV, providing the structure-antiviral activity relationship for the development of anti-JEV agents.


Assuntos
Antivirais/uso terapêutico , Efeito Citopatogênico Viral/efeitos dos fármacos , Vírus da Encefalite Japonesa (Espécie)/efeitos dos fármacos , Antivirais/farmacologia , Humanos
10.
Virus Res ; 273: 197767, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31560964

RESUMO

Human coronavirus NL63 (HCoV-NL63), one of the main circulating HCoVs worldwide, causes respiratory tract illnesses like runny nose, cough, bronchiolitis and pneumonia. Recently, a severe respiratory illness outbreak of HCoV-NL63 has been reported in a long-term care facility. Sambucus FormosanaNakai, a species of elderberry, is a traditional medicinal herb with anti-inflammatory and antiviral potential. The study investigated the antiviral activity of Sambucus FormosanaNakai stem ethanol extract and some phenolic acid constituents against HCoV-NL63. The extract was less cytotoxic and concentration-dependently increased anti-HCoV-NL63 activities, including cytopathicity, sub-G1 fraction, virus yield (IC50 = 1.17 µg/ml), plaque formation (IC50 = 4.67 µg/ml) and virus attachment (IC50 = 15.75 µg/ml). Among the phenolic acid constituents in Sambucus FormosanaNakai extract, caffeic acid, chlorogenic acid and gallic acid sustained the anti-HCoV-NL63 activity that was ranked in the following order of virus yield reduction: caffeic acid (IC50 = 3.54 µM) > chlorogenic acid (IC50 = 43.45 µM) > coumaric acid (IC50 = 71.48 µM). Caffeic acid significantly inhibited the replication of HCoV-NL63 in a cell-type independent manner, and specifically blocked virus attachment (IC50 = 8.1 µM). Therefore, the results revealed that Sambucus Formosana Nakai stem ethanol extract displayed the strong anti-HCoV-NL63 potential; caffeic acid could be the vital component with anti-HCoV-NL63 activity. The finding could be helpful for developing antivirals against HCoV-NL63.


Assuntos
Antivirais/farmacologia , Coronavirus Humano NL63/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Hidroxibenzoatos/farmacologia , Extratos Vegetais/farmacologia , Sambucus/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Infecções por Coronavirus , Células Epiteliais/virologia , Humanos , Hidroxibenzoatos/química , Concentração Inibidora 50 , Rim/citologia , Rim/virologia , Macaca mulatta , Extratos Vegetais/química , Caules de Planta/química , Sistema Respiratório/citologia , Sistema Respiratório/virologia , Ligação Viral/efeitos dos fármacos
11.
Angew Chem Int Ed Engl ; 58(43): 15344-15348, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31449706

RESUMO

An unusual tetra-nuclear linear cyanido-bridged complex [Ru2 (µ-ap)4 -CN-Ru2 (µ-ap)4 ](BPh4 ) (1) (ap=2-anilinopyridinate) has been synthesized and well characterized. The crystallographic data, magnetic measurement, IR, EPR and theoretical calculation results demonstrate that complex 1 is the first example of mixed spin Ru2 5+ -based complex with uncommon electronic configurations of S=1/2 for the cyanido-C bound Ru2 5+ and S=3/2 for the cyanido-N bound Ru2 5+ . This phenomenon can be understood by the theoretical calculation results that from the precursor Ru2 (µ-ap)4 (CN) (S=3/2) to complex 1 the energy gap between π* and δ* orbitals of the cyanido-C bound Ru2 5+ core increases from 0.57 to 1.61 eV due to the enhancement of asymmetrical π back-bonding effect, but that of the cyanido-N bound Ru2 5+ core is essential identical (0.56 eV). Besides, the analysis of UV/Vis-NIR spectra suggests that there exists metal to metal charge transfer (MMCT) from the cyanido-N bound Ru2 5+ (S=3/2) to the cyanido-C bound Ru2 5+ (S=1/2), supported by the TDDFT calculations.

12.
Biomedicine (Taipei) ; 9(2): 13, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31124459

RESUMO

Aeromonas peritonitis is a rare, but serious infection, as associated with spontaneous bacterial peritonitis, peritonitis in chronic ambulatory peritoneal dialysis, and intestinal perforation. Here, we reported a case of monomicrobial non-neutrocytic bacterascites caused by Aeromonas hydrophila (A. hydrophila). The patient, a 57-year-old man who had a history of alcoholic liver disease and chronic hepatitis C-related Child- Pugh class C liver cirrhosis, was admitted to our hospital with fever, dyspnea and a localized wound pain over left ankle. Ascitic fluid analysis demonstrated that ascitic polymorphonuclear cell count was 30 cells/ mm3. Empirical antimicrobial treatment with a combination of ceftriaxone and clindamycin were administered. However, the patient died due to fatal septic shock on Day 3. His blood and ascites cultures were positive for A. hydrophila. The case report presents the diagnosis, management, and literature review of Aeromonas monomicrobial non-neutrocytic bacterascites.

13.
Inorg Chem ; 58(6): 3990-3999, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30821449

RESUMO

Mid- and far-infrared nonlinear optical (MFIR NLO) materials are important in modern laser technologies. However, it is very challenging to develop materials that can achieve a subtle balance between the key requirements, such as large NLO response, high laser-induced damage threshold (LIDT), wide IR transparency, and phase-matching. In this work, a new wide IR transparency (0.38-15.3 µm) NLO crystal Ba10In6Zn7S26 (SS26) is synthesized. Further, its composite system Ba10In6Zn7S26- nZnS is synthesized by eutectic reaction. In particular, Ba10In6Zn7S26-14ZnS (SS40) shows excellent balanced NLO performance that includes a large band gap of 3.05 eV, high LIDT (13.3 × AgGaS2), large second harmonic generation (SHG) response (2.1 × AgGaS2 at 2050 nm, 5.2 × KDP at 1064 nm), and wide optical transmission window (0.37-15.4 µm). Importantly, the phase-matching condition is realized for SS40 by interfaces formed between the crystal face (112) of matrix SS26 and the crystal face (111) of reinforcement cubic ZnS by topological chemical reaction, and the NLO performance can be tuned by different concentrations of ZnS. First-principles simulations are employed to study NLO properties of SS26 and the interfaces. This work demonstrates that SS40 is a promising MFIR NLO material, and tuning components of the composite material system is a useful way to develop new MFIR NLO materials with excellent comprehensive performance.

14.
Biomol Ther (Seoul) ; 27(1): 54-62, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30261716

RESUMO

Cis-3-O-p-hydroxycinnamoyl ursolic acid (HCUA), a triterpenoid compound, was purified from Elaeagnus oldhamii Maxim. This traditional medicinal plant has been used for treating rheumatoid arthritis and lung disorders as well as for its anti-inflammation and anticancer activities. This study aimed to investigate the anti-proliferative and apoptotic-inducing activities of HCUA in oral cancer cells. HCUA exhibited anti-proliferative activity in oral cancer cell lines (Ca9-22 and SAS cells), but not in normal oral fibroblasts. The inhibitory concentration of HCUA that resulted in 50% viability was 24.0 µM and 17.8 µM for Ca9-22 and SAS cells, respectively. Moreover, HCUA increased the number of cells in the sub-G1 arrest phase and apoptosis in a concentration-dependent manner in both oral cancer cell lines, but not in normal oral fibroblasts. Importantly, HCUA induced p53-mediated transcriptional regulation of pro-apoptotic proteins (Bax, Bak, Bim, Noxa, and PUMA), which are associated with mitochondrial apoptosis in oral cancer cells via the loss of mitochondrial membrane potential. HCUA triggered the production of intracellular reactive oxygen species (ROS) that was ascertained to be involved in HCUA-induced apoptosis by the ROS inhibitors YCG063 and N-acetyl-L-cysteine. As a result, HCUA had potential antitumor activity to oral cancer cells through eliciting ROS-dependent and p53-mediated mitochondrial apoptosis. Overall, HCUA could be applicable for the development of anticancer agents against human oral cancer.

15.
J Am Chem Soc ; 139(36): 12474-12479, 2017 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-28837322

RESUMO

Luminescent supramolecular lanthanide edifices have many potential applications in biology, environments, and materials science. However, it is still a big challenge to improve the luminescent performance of multinuclear lanthanide assemblies in contrast to their mononuclear counterparts. Herein, we demonstrate that combination of intraligand charge transfer (ILCT) sensitization and coordination-driven self-assembly gives birth to bright EuIII tetrahedral cages with a record emission quantum yield of 23.1%. The ILCT sensitization mechanism has been unambiguously confirmed by both time-dependent density functional theory calculation and femtosecond transient absorption studies. Meanwhile, dual-responsive sensing toward both anions and cations has been demonstrated making use of the ILCT transition on the ligand. Without introduction of additional recognition units, high sensitivity and selectivity are revealed for the cage in both turn-off luminescent sensing toward I- and turn-on sensing toward Cu2+. This study offers important design principles for the future development of luminescent lanthanide molecular materials.

16.
J Am Chem Soc ; 139(24): 8237-8244, 2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-28558197

RESUMO

Lanthanide-containing molecules have many potential applications in material science and biology, that is, luminescent sensing/labling, MRI, magnetic refrigeration, and catalysis among others. Coordination-directed self-assembly has shown great power in the designed construction of well-defined supramolecular systems. However, application of this strategy to the lanthanide edifices is challenging due to the complicated and greatly labile coordination numbers and geometries for lanthanides. Here we demonstrate a sensitive structural switching phenomenon during the stereocontrolled self-assembly of a group of Ln2nL3n (Ln for lanthanides, L for organic ligands, and n = 1, 2, 4) compounds. Systematic variation of the offset distances between the two chelating arms on the bis(tridentate) ligands dictated the final outcomes of the lanthanide assembly, ranging from Ln2L3 helicates and Ln4L6 tetrahedra to Ln8L12 cubes. Remarkably, the borderline case leading to the formation of a mixture of the helicate and the tetrahedron was clearly revealed. Moreover, the concentration-dependent self-assembly of an unprecedented cubic Ln8L12 complex was also confirmed. The luminescent lanthanide cubes can serve as excellent turn-off sensors in explosives detection, featuring high selectivity and sensitivity toward picric acid. All complexes were confirmed by NMR, ESI-TOF-MS, and single crystal X-ray diffraction studies. Our results provide valuable design principles for the coordination self-assembly of multinuclear functional lanthanide architectures.

17.
Angew Chem Int Ed Engl ; 56(6): 1605-1609, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28079947

RESUMO

The heterometallic complexes trans-[Cp(dppe)FeNCRu(o-bpy)CNFe(dppe)Cp][PF6 ]n (1[PF6 ]n , n=2, 3, 4; o-bpy=1,2-bis(2,2'-bipyridyl-6-yl)ethane, dppe=1,2-bis(diphenylphosphino)ethane, Cp=1,3-cyclopentadiene) in three distinct states have been synthesized and fully characterized. 13+ [PF6 ]3 and 14+ [PF6 ]4 are the one- and two-electron oxidation products of 12+ [PF6 ]2 , respectively. The investigated results suggest that 1[PF6 ]3 is a Class II mixed valence compound. 1[PF6 ]4 after a thermal treatment at 400 K shows an unusually delocalized mixed valence state of [FeIII -NC-RuIII -CN-FeII ], which is induced by electron transfer from the central RuII to the terminal FeIII in 1[PF6 ]4 , which was confirmed by IR spectroscopy, magnetic data, and EPR and Mössbauer spectroscopy.

18.
Chemphyschem ; 18(5): 519-525, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28019076

RESUMO

We theoretically evaluated the integrated knowledge that contributes to conversion efficiency, including the phonon, photon, and electron properties of infrared nonlinear optical materials such as SnGa4 Q7 (Q=S, Se), which are terahertz (THz) sources. Specifically, we developed a new formula to calculate the susceptibility of the difference frequency generation (DFG) optical process. By evaluating the characteristics of the materials themselves in the THz region, we found that a larger nonlinear susceptibility or a large figure of merit resulted in a large efficiency of the THz source by comparing the findings of SnGa4 Se7 and SnGa4 S7 under the same experimental conditions; furthermore, THz absorption was found to reduce the efficiency of the THz source for the two SnGa4 Q7 (Q=S, Se) materials. The efficiency of the THz source also depended on the experimental conditions. A large crystal size, strong pump intensity, and small THz wavelength resulted in better efficiency of the THz source based on the DFG process. The efficiency was found to be a comprehensive index to evaluate the THz source based on the DFG process.

19.
J Microbiol Immunol Infect ; 50(6): 763-770, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26746130

RESUMO

BACKGROUND/PURPOSE: Human coronavirus (HCoV) NL63 is recognized in association with upper or lower respiratory tract illnesses in children. This study surveyed the prevalence of HCoV-NL63 and influenza viruses in patients with influenza-like illness in Taiwan during 2010-2011. METHODS: Throat samples from 107 hospitalized patients with pneumonia and 175 outpatients with influenza-like illness were examined using real-time polymerase chain reaction assays with virus-specific primers, and then virus-positive specimens were confirmed by sequencing the polymerase chain reaction products. RESULTS: HCoV-NL63 infection was identified in 8.4% (9/107) of hospitalized patients with pneumonia, but not found in outpatients with influenza-like illness. Age distribution of HCoV-NL63 infection in hospitalized patients with pneumonia indicated that the group aged 16-25 years (20%) had the highest positive rate compared with the other groups, and exhibited a similar age-specific pattern to influenza A/H1N1 infection, but not influenza A/H3N2 and B infections in hospitalized patients. Seasonal prevalence of HCoV-NL63 infection was late winter, overlapping the highest peak of the influenza A/H1N1 epidemic during December 2010 to March 2011 in Taiwan. Co-infection of HCoV-NL63 and influenza A/H1N1 was detected in three hospitalized patients. Clinical manifestation analysis indicated that the main symptoms for HCoV-NL63 infection included fever (88.9%), cough (77.8%), and pneumonia (100%). Co-infection caused significantly higher rates of breathing difficulties, cough, and sore throat than those of single infection with HCoV-NL63 and influenza A/H1N1. Phylogenetic analysis indicated a low level of heterogeneity between Taiwan and global HCoV-NL63 strains. CONCLUSION: Understanding epidemiology of HCoV-NL63 in Taiwan provides an insight for worldwide surveillance of HCoV-NL63 infection.


Assuntos
Infecções por Coronavirus/epidemiologia , Coronavirus Humano NL63/classificação , Influenza Humana/epidemiologia , Pneumonia/epidemiologia , Adolescente , Adulto , Idoso , Sequência de Bases , Coinfecção/patologia , Coinfecção/virologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Coronavirus Humano NL63/isolamento & purificação , Coronavirus Humano NL63/patogenicidade , Humanos , Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/patologia , Influenza Humana/virologia , Pessoa de Meia-Idade , Filogenia , Pneumonia/diagnóstico , Pneumonia/patologia , Pneumonia/virologia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Estações do Ano , Análise de Sequência de RNA , Taiwan/epidemiologia , Adulto Jovem
20.
Lancet Oncol ; 17(11): 1590-1598, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27733243

RESUMO

BACKGROUND: Few effective treatments exist for patients with advanced urothelial carcinoma that has progressed after platinum-based chemotherapy. We assessed the activity and safety of nivolumab in patients with locally advanced or metastatic urothelial carcinoma whose disease progressed after previous platinum-based chemotherapy. METHODS: In this phase 1/2, multicentre, open-label study, we enrolled patients (age ≥18 years) with urothelial carcinoma of the renal pelvis, ureter, bladder, or urethra at 16 sites in Finland, Germany, Spain, the UK, and the USA. Patients were not selected by PD-L1 expression, but tumour PD-L1 membrane expression was assessed retrospectively. Patients received nivolumab 3 mg/kg intravenously every 2 weeks until disease progression or treatment discontinuation because of unacceptable toxicity or other protocol-defined reasons, whichever occurred later. The primary endpoint was objective response by investigator assessment. All patients who received at least one dose of the study drug were included in the analyses. We report an interim analysis of this ongoing trial. CheckMate 032 is registered with ClinicalTrials.gov, NCT01928394. FINDINGS: Between June 5, 2014, and April 24, 2015, 86 patients with metastatic urothelial carcinoma were enrolled in the nivolumab monotherapy group and 78 received at least one dose of treatment. At data cutoff (March 24, 2016), the minimum follow-up was 9 months (median 15·2 months, IQR 12·9-16·8). A confirmed investigator-assessed objective response was achieved in 19 (24·4%, 95% CI 15·3-35·4) of 78 patients. Grade 3-4 treatment-related adverse events occurred in 17 (22%) of 78 patients; the most common were elevated lipase (four [5%]), elevated amylase (three [4%]), and fatigue, maculopapular rash, dyspnoea, decreased lymphocyte count, and decreased neutrophil count (two [3%] each). Serious adverse events were reported in 36 (46%) of 78 patients and eight (10%) had a serious adverse event judged to be treatment related. Two (3%) of 78 patients discontinued because of treatment-related adverse events (grade 4 pneumonitis and grade 4 thrombocytopenia) and subsequently died. INTERPRETATION: Nivolumab monotherapy was associated with a substantial and durable clinical response and a manageable safety profile in previously treated patients with locally advanced or metastatic urothelial carcinoma. These data support further investigation of nivolumab monotherapy in advanced urothelial carcinoma. FUNDING: Bristol-Myers Squibb.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Urológicas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/patologia , Nivolumabe , Neoplasias Urológicas/patologia
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