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1.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35101990

RESUMO

Emerging evidence indicates that a subset of RNA molecules annotated as noncoding contain short open reading frames that code for small functional proteins called microproteins, which have largely been overlooked due to their small size. To search for cardiac-expressed microproteins, we used a comparative genomics approach and identified mitolamban (Mtlbn) as a highly conserved 47-amino acid transmembrane protein that is abundantly expressed in the heart. Mtlbn localizes specifically to the inner mitochondrial membrane where it interacts with subunits of complex III of the electron transport chain and with mitochondrial respiratory supercomplexes. Genetic deletion of Mtlbn in mice altered complex III assembly dynamics and reduced complex III activity. Unbiased metabolomic analysis of heart tissue from Mtlbn knockout mice further revealed an altered metabolite profile consistent with deficiencies in complex III activity. Cardiac-specific Mtlbn overexpression in transgenic (TG) mice induced cardiomyopathy with histological, biochemical, and ultrastructural pathologic features that contributed to premature death. Metabolomic analysis and biochemical studies indicated that hearts from Mtlbn TG mice exhibited increased oxidative stress and mitochondrial dysfunction. These findings reveal Mtlbn as a cardiac-expressed inner mitochondrial membrane microprotein that contributes to mitochondrial electron transport chain activity through direct association with complex III and the regulation of its assembly and function.


Assuntos
Cardiomiopatias/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias Cardíacas/metabolismo , Proteínas Mitocondriais/metabolismo , Miocárdio/metabolismo , Animais , Cardiomiopatias/genética , Células Cultivadas , Complexo III da Cadeia de Transporte de Elétrons/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Mitocôndrias Cardíacas/genética , Proteínas Mitocondriais/genética , Especificidade de Órgãos
2.
Bioorg Med Chem ; 98: 117578, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38154348

RESUMO

As the ß-phenyl-α,ß-unsaturated carbonyl (PUSC) structure was previously identified to play a key role in tyrosinase inhibition, 14 analogs with a PUSC structure built on a thiazol-4(5H)-one scaffold were synthesized using Knoevenagel condensation to serve as potential tyrosinase inhibitors. Through mushroom tyrosinase inhibition experiments, two analogs 9 and 11 were identified as potent tyrosinase inhibitors, with 11 exhibiting an IC50 value of 0.4 ± 0.01 µM, which indicates its 26-fold greater potency than kojic acid. Kinetic studies using Lineweaver-Burk plots revealed that 9 and 11 are competitive and mixed-type inhibitors, respectively; these kinetic results were supported by docking simulations. According to the B16F10 cell-based experiments, 9 and 11 inhibited melanogenesis more effectively than kojic acid due to their potent cellular tyrosinase inhibitory activity. In addition, analogs 9 and 11 exhibited moderate-to-strong antioxidant capacity, scavenging ABTS+, DPPH, and ROS radicals. In particular, analog 12 with a catechol moiety exhibited very strong ROS-scavenging activity, similar to Trolox. These results suggest that analogs 9 and 11, which exhibit potent tyrosinase inhibitory activity in mushroom and mammalian cells and anti-melanogenic effects in B16F10 cells, are promising antibrowning agents for crops and skin lightening agents for hyperpigmentation-related diseases.


Assuntos
Agaricales , Monofenol Mono-Oxigenase , Animais , Antioxidantes/farmacologia , Relação Estrutura-Atividade , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Cinética , Espécies Reativas de Oxigênio , Simulação de Acoplamento Molecular , Melaninas , Mamíferos/metabolismo
3.
Bioorg Chem ; 150: 107586, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38955001

RESUMO

Compounds with sulfhydryl substituents and azole compounds exhibit potent anti-tyrosinase potency. 2-Thiobenzothiazole (2-TBT), a hybrid structure of sulfhydryl and azole, exists in two tautomeric forms, with the thione form being predominant according to several studies. 2-TBT derivatives were synthesized as potential tyrosinase inhibitors as the thione tautomeric form has the same N-CS moiety as phenylthiourea (PTU), which is suitable for chelation with the copper ions present in the tyrosinase active site. Eight of the ten 2-TBT derivatives inhibited the monophenolase and diphenolase activities of mushroom tyrosinase, with IC50 values of 0.02-0.83 µM. Kinetic studies and molecular dynamics simulations were performed to determine their mode of action and confirm that the 2-TBT derivatives bind to the tyrosinase active site with high stability. Derivatives 3, 4, 8, and 10 strongly inhibited melanogenesis in B16F10 cells in a pattern similar to the results of cellular tyrosinase inhibition, thereby suggesting that their ability to inhibit melanogenesis was due to their tyrosinase inhibitory activity. In a depigmentation experiment using zebrafish embryos, all 2-TBT derivatives showed better potency than kojic acid, even at 400 to 2000 times lower concentration, and 1 and 10 reduced zebrafish larva pigmentation more strongly than PTU even at 20 times lower concentration. Experiments investigating the changes in tyrosinase inhibitory activity of 2-TBT derivatives in the presence and absence of CuSO4 and their copper chelating ability supported that these derivatives exert their anti-melanogenic effect by chelating the copper ions of tyrosinase. These results suggest that 2-TBT derivatives are promising candidates for the treatment of hyperpigmentation-related disorders.

4.
J Gerontol Soc Work ; 67(4): 492-514, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590208

RESUMO

This pilot randomized controlled trial aimed to evaluate the feasibility and potential outcomes of an innovative 16-session multicomponent intervention model to improve cognitive abilities in older adults with mild cognitive impairment (MCI) by promoting healthy lifestyle, cognitive skills, tai chi and mindfulness practices. This study was a multicentre, randomized controlled, two-arm, parallel-group, unblinded trial in Hong Kong. 57 Chinese older adults with MCI recruited from three local elderly centers were randomly assigned to either the control or intervention group. The study results support the feasibility and efficacy of the multicomponent intervention, and recommend future larger-scale randomized control trials.


Assuntos
Disfunção Cognitiva , Humanos , Disfunção Cognitiva/terapia , Idoso , Masculino , Feminino , Projetos Piloto , Hong Kong , Idoso de 80 Anos ou mais , Tai Chi Chuan/métodos , Atenção Plena/métodos , Cognição , Pessoa de Meia-Idade
5.
Oncologist ; 28(2): 131-138, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36321912

RESUMO

PURPOSE: The objective of this study was to determine whether differences in patients' race/ethnicity, preferred language, and other factors were associated with patient enrollment in oncology research studies. PATIENTS AND METHODS: We conducted a retrospective cross-sectional analysis of all adults (>18 and ≤90) seen at a large, metropolitan cancer center from 2005 to 2015, examining if enrollment to a research study, varied by race/ethnicity, preferred language, comorbidities, gender, and age. RESULTS: A total of 233 604 patients were available for initial analysis. Of these, 93 278 (39.9%) were enrolled in a research protocol (therapeutic and non-therapeutic studies). Patients who self-reported their race/ethnicity as Native, Other, Unknown, or Refuse to Answer were less likely to be enrolled on a study. Patients with one or more comorbidities, and those whose preferred language was English, were more likely to be enrolled on a research study. A logistic regression model showed that, although Non-Hispanic Black patients were more likely to have one or more comorbidities and had a higher proportion of their subset selecting English as their preferred language, they were less likely to be enrolled on a study, than our largest population, Non-Hispanic/White patients. CONCLUSIONS: We identified differences in research study enrollment based on preferred language, and within race/ethnicity categories including Native-Populations, Other, Unknown or Refuse to Answer compared to Non-Hispanic/White patients. We also highlighted the lower odds of enrollment among Non-Hispanic/Black patients, in the setting of factors such as comorbidities and English language preference, which were otherwise found to be positive predictors of enrollment. Further investigation is needed to design targeted interventions to reduce disparities in oncology research study enrollment, with particular focus on language diversity.


Assuntos
Etnicidade , Neoplasias , Adulto , Humanos , Estudos Retrospectivos , Estudos Transversais , Neoplasias/epidemiologia , Neoplasias/terapia , Idioma
6.
Oncologist ; 28(4): 351-357, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36745014

RESUMO

BACKGROUND: Adjuvant anti-PD1 treatment improves relapse-free survival (RFS) but has not been shown to improve overall survival (OS) in melanoma and is associated with risks of immune-related adverse events (irAEs), some permanent. We identified factors patients consider in deciding whether to undergo adjuvant anti-PD1 treatment and assessed prospective health-related quality of life (HRQoL), treatment satisfaction, and decisional regret. PATIENTS AND METHODS: Patients with stage IIIB-IV cutaneous melanoma and free of disease, were candidates for adjuvant anti-PD1 immunotherapy, and had not yet discussed adjuvant treatment options with their oncologist were eligible. Participants viewed a 4-minute informational video tailored to their disease stage which communicated comprehensive, quantitative information about the risk of relapse both with and without adjuvant treatment, and risks of each irAE before deciding whether or not to opt for adjuvant therapy. We collected data on demographics, HRQoL, and attitudes toward adjuvant treatment over 1 year. RESULTS: 14/34 patients (41%) opted for adjuvant anti-PD1 immunotherapy, 20/34 (59%) opted for observation. Patients choosing adjuvant immunotherapy scored higher on HRQoL social well-being at pre-treatment, were more likely to endorse positive statements about adjuvant immunotherapy, and to perceive that their physician preferred adjuvant therapy. They had lower decisional regret and higher satisfaction, even if they experienced toxicity or recurrence. CONCLUSIONS: When provided with comprehensive quantitative information about risks and benefits of adjuvant anti-PD1 immunotherapy, 20/34 (59%) of patients opted for observation. Patients choosing adjuvant immunotherapy had lower decisional regret and higher satisfaction over time even if they had poorer outcomes in treatment.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/terapia , Neoplasias Cutâneas/terapia , Qualidade de Vida , Recidiva Local de Neoplasia , Imunoterapia , Melanoma Maligno Cutâneo
7.
Bioorg Chem ; 135: 106504, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37015153

RESUMO

Flavone derivatives were designed and synthesized based on the hypothesis that flavones containing the ß-phenyl-α,ß-unsaturated carbonyl (PUSC) scaffold have potential anti-tyrosinase activity. Flavones 1a and 1e inhibited mushroom tyrosinase more potently than kojic acid, and 1e inhibited monophenolase and diphenolase 61- and 28-fold more than kojic acid, respectively. Kinetic studies on mushroom tyrosinase indicated that 1a and 1e competitively inhibit monophenolase and diphenolase, and docking results supported these results. In an in vitro assay using B16F10 murine cells, 1a and 1e inhibited melanin production more potently than kojic acid, and this was attributed to the inhibition of tyrosinase. Furthermore, 1a and 1e strongly scavenged DPPH and ABTS radicals and ROS, which suggested that their antioxidant properties were at least partly responsible for their anti-melanogenic effects. Moreover, flavone 1a also inhibited the gene expressions of the melanogenesis-related genes tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2. Our findings that flavone derivatives (i) directly inhibit tyrosinase, (ii) act as antioxidants, and (iii) inhibit the expressions of melanogenesis-related genes suggest their potential use as natural melanogenesis inhibitors. Furthermore, the study confirms that the PUSC scaffold confers anti-tyrosinase activity.


Assuntos
Agaricales , Flavonas , Animais , Camundongos , Monofenol Mono-Oxigenase , Melaninas , Cinética , Inibidores Enzimáticos/química , Flavonas/farmacologia
8.
Bioorg Chem ; 136: 106557, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37121106

RESUMO

Acute lung injury (ALI) is a common respiratory disease caused by local or systemic inflammatory reaction. Based on the natural 7-chain diaryl anti-inflammatory framework, a series of diimide indoles derivatives were designed by combining curcumin and indole in this study. The synthesis of diimide compounds was extended using dichloromethane (DCM) as solvent and 1,1'-carbonyldiimidazole (CDI) and sodium hydride (NaH) as double activators, and a total of 40 diimide-indole derivatives were obtained. The results of in vitro anti-inflammatory activity showed that most compounds could inhibit the production of interleukin-6 (IL-6) better than curcumin and indomethacin. Among the compounds, the IC50 of compound 11f on IL-6 reached 1.05 µM with no obvious cytotoxic side effects. Mechanistically, compound 11f could block the expression of NF-κB P65 phosphorylation, and nuclear translocation of P65. The acute toxicity tests in-vivo also showed no obvious toxicity in mice after the intragastric administration of 1000 mg/kg. In addition, the compound 11f could significantly inhibit the LPS-induced inflammatory response in mice and reduce the number of neutrophils and wet/dry lung weight ratio, thereby alleviating ALI. These results indicated that the novel diimide indoles were promising anti-inflammatory agents for the treatment of ALI.


Assuntos
Lesão Pulmonar Aguda , Curcumina , Camundongos , Animais , NF-kappa B/metabolismo , Interleucina-6/farmacologia , Curcumina/farmacologia , Transdução de Sinais , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Anti-Inflamatórios/efeitos adversos , Lipopolissacarídeos/efeitos adversos
9.
Nature ; 551(7681): 494-497, 2017 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-29168804

RESUMO

Ultralow-velocity zones (ULVZs) at Earth's core-mantle boundary region have important implications for the chemical composition and thermal structure of our planet, but their origin has long been debated. Hydrogen-bearing iron peroxide (FeO2Hx) in the pyrite-type crystal structure was recently found to be stable under the conditions of the lowermost mantle. Using high-pressure experiments and theoretical calculations, we find that iron peroxide with a varying amount of hydrogen has a high density and high Poisson ratio as well as extremely low sound velocities consistent with ULVZs. Here we also report a reaction between iron and water at 86 gigapascals and 2,200 kelvin that produces FeO2Hx. This would provide a mechanism for generating the observed volume occupied by ULVZs through the reaction of about one-tenth the mass of Earth's ocean water in subducted hydrous minerals with the effectively unlimited reservoir of iron in Earth's core. Unlike other candidates for the composition of ULVZs, FeO2Hx synthesized from the superoxidation of iron by water would not require an extra transportation mechanism to migrate to the core-mantle boundary. These dense FeO2Hx-rich domains would be expected to form directly in the core-mantle boundary region and their properties would provide an explanation for the many enigmatic seismic features that are observed in ULVZs.

10.
J Prosthet Dent ; 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36635136

RESUMO

STATEMENT OF PROBLEM: Three-dimensional (3D) printers should be capable of fabricating products with high accuracy for potential use in a wide range of dental applications. The trueness and surface characteristics of 3D-printed casts made with different technologies remain unclear. PURPOSE: The purpose of this in vitro study was to evaluate the trueness and surface characteristics of 4 types of dental casts printed using 6 different 3D printers. MATERIAL AND METHODS: Four dental casts prepared for intracoronal and extracoronal restorations were printed using 6 different 3D printers-2 printers of each printing technology (FDM: Creator, Lugo; DLP: D2, ND5100; SLA: Form 2, Form 3). The printed casts were scanned to obtain standard tessellation language (STL) data sets that were superimposed onto the reference to evaluate their trueness (n=15). Trueness was measured based on overall deviations for each cast and for sectional deviations within the cavities. For qualitative evaluation, the surface characteristics of the 3D-printed casts were analyzed by using a digital camera, stereomicroscope, and scanning electron microscope. Statistical analyses were conducted using the Kruskal-Wallis test, followed by multiple Mann-Whitney U tests for pairwise comparisons among groups (α=.05). RESULTS: The overall median trueness values were lowest with the Form 3 (27.9 µm), followed by the ND5100 (30.0 µm), Lugo (37.1 µm), D2 (41.4 µm), Form 2 (46.9 µm), and Creator (83.3 µm) (P<.05). Sectional deviations within the cavity were generally greater than overall deviation. Macroscopic and microscopic images showed that the reproduced casts had the smoothest surface with the SLA, followed by the DLP and FDM printers. Horizontal layers were more discernible with the FDM printer. CONCLUSIONS: The trueness of the 3D-printed casts was influenced by the type of tooth preparation and was printer dependent. Among the tested 3D printers, the Form 3 produced the most accurate casts, while the Creator produced the least accurate casts.

11.
Opt Express ; 30(9): 14677-14685, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473207

RESUMO

We investigated the possibility of using long excitation pulses in fluorescence lifetime imaging microscopy (FLIM) using phasor analysis. It has long been believed that the pulse width of an excitation laser must be shorter than the lifetime of a fluorophore in a time-domain FLIM system. Even though phasor analysis can effectively minimize the pulse effect by using deconvolution, the precision of a measured lifetime can be degraded seriously. Here, we provide a fundamental theory on pulse-width-dependent measurement precisions in lifetime measurement in the phasor plane. Our theory predicts that high-precision lifetimes can be obtained even with a laser whose pulse width is four times larger than the lifetime of a fluorophore. We have experimentally demonstrated this by measuring the lifetimes of fluorescence probes with 2.57 ns and 3.75 ns lifetimes by using various pulse widths (0.52-38 ns) and modulation frequencies (10-200 MHz). We believe our results open a new possibility of using long pulse-width lasers for high-precision FLIM.

12.
Bioorg Chem ; 127: 105985, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35809512

RESUMO

We previously discovered that triterpenoid saponin platycodin D inhibits the SARS-CoV-2 entry to the host cell. Herein, we synthesized various saponin derivatives and established a structure-activity relationship of saponin-based antiviral agents against SARS-CoV-2. We discovered that the C3-glucose, the C28-oligosaccharide moiety that consist of (→3)-ß-d-Xyl-(1 â†’ 4)-α-l-Rham-(1 â†’ 2)-ß-d-Ara-(1 â†’ ) as the last three sugar units, and the C16-hydroxyl group were critical components of saponin-based coronavirus cell entry inhibitors. These findings enabled us to develop minimal saponin-based antiviral agents that are equipotent to the originally discovered platycodin D. We found that our saponin-based antiviral agents inhibited both the endosomal and transmembrane protease serine 2-mediated cell surface viral entries. Cell fusion assay experiment revealed that our newly developed compounds inhibit the SARS-CoV-2 entry by blocking the fusion between the viral and host cell membranes. The effectiveness of the newly developed antiviral agents over various SARS-CoV-2 variants hints at the broad-spectrum antiviral efficacy of saponin-based therapeutics against future coronavirus variants.


Assuntos
COVID-19 , Saponinas , Antivirais/farmacologia , Humanos , Fusão de Membrana , SARS-CoV-2 , Saponinas/farmacologia , Relação Estrutura-Atividade
13.
Bioorg Med Chem Lett ; 45: 128134, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34044120

RESUMO

A series of O-substituted analogs of the C-ring-truncated scaffold of deguelin designed as heat shock protein 90 (HSP90) C-terminal inhibitors were investigated as novel antitumor agents against human epidermal growth factor receptor 2 (HER2)-positive breast cancer. Among the synthesized compounds, compound 37 displayed significant inhibition in both trastuzumab-sensitive and trastuzumab-resistant breast cancer cells with little cytotoxicity to normal cells. Mechanistic studies of compound 37 carried out by HSP90α C-terminal inhibitor screening, the induction of the heat shock response and downregulation of HSP90 client proteins indicated that the antitumor activity of 37 in breast cancer cells could be attributed to the destabilization and inactivation of HSP90 client proteins by the binding of 37 to the C-terminal domain of HSP90. A molecular docking study of compound 37 with a HSP90 homology model indicated that its S-isomer fit well in the ATP binding site of the C-terminal domain, forming key interactions.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Descoberta de Drogas , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Rotenona/análogos & derivados , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Rotenona/síntese química , Rotenona/química , Rotenona/farmacologia , Relação Estrutura-Atividade
14.
J Prosthet Dent ; 126(6): 779-786, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33176925

RESUMO

STATEMENT OF PROBLEM: Studies evaluating the trueness of intraoral scanners (IOSs) at anatomic locations within an intracoronal preparation are lacking. PURPOSE: The purpose of this in vitro study was to evaluate the trueness of digital scans obtained by IOSs at the margin and intaglio surfaces of intracoronal preparations. MATERIAL AND METHODS: Six IOSs (CEREC Omnicam, E4D, FastScan, iTero, TRIOS, Zfx IntraScan) were used to obtain digital scans of various intracoronal preparations. Standard tessellation language (STL) data sets obtained from a reference scanner and each IOS were superimposed, and the deviation of the digital casts was assessed at multiple measuring points along the margin and intaglio surfaces of each preparation. The Kruskal-Wallis test and multiple Mann-Whitney tests were used to detect differences in trueness (α=.05). RESULTS: The overall median trueness values were lowest for TRIOS (23.9 µm), followed by Zfx IntraScan (24.6 µm), iTero (25.4 µm), FastScan (26.1 µm), CEREC Omnicam (26.9 µm), and E4D (77.5 µm). The greatest deviation was generally observed at the line angles between the preparation surfaces. The axiogingival line angle was the most error-prone location in the cavity preparations. An increased tendency to produce a more accurate impression was observed when the cavity had a greater width and more divergent walls. CONCLUSIONS: The trueness of digital scans was influenced by the type of IOS and the location within a prepared cavity. The trueness decreased at the line angles between the preparation surfaces, particularly at the axiogingival line angle. Among the tested IOSs, E4D produced the least accurate digital scans.


Assuntos
Técnica de Moldagem Odontológica , Modelos Dentários , Desenho Assistido por Computador , Arco Dental , Imageamento Tridimensional
15.
Anal Chem ; 92(16): 11357-11364, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32806905

RESUMO

Charge detection mass spectrometry is a single particle technique where the masses of individual ions are determined from simultaneous measurements of each ion's m/z ratio and charge. The ions pass through a conducting cylinder, and the charge induced on the cylinder is detected. The cylinder is usually placed inside an electrostatic linear ion trap so that the ions oscillate back and forth through the cylinder. The resulting time domain signal is analyzed by fast Fourier transformation; the oscillation frequency yields the m/z, and the charge is determined from the magnitudes. The mass resolving power depends on the uncertainties in both quantities. In previous work, the mass resolving power was modest, around 30-40. In this work we report around an order of magnitude improvement. The improvement was achieved by coupling high-accuracy charge measurements (obtained with dynamic calibration) with higher resolution m/z measurements. The performance was benchmarked by monitoring the assembly of the hepatitis B virus (HBV) capsid. The HBV capsid assembly reaction can result in a heterogeneous mixture of intermediates extending from the capsid protein dimer to the icosahedral T = 4 capsid with 120 dimers. Intermediates of all possible sizes were resolved, as well as some overgrown species. Despite the improved mass resolving power, the measured peak widths are still dominated by instrumental resolution. Heterogeneity makes only a small contribution. Resonances were observed in some of the m/z spectra. They result from ions with different masses and charges having similar m/z values. Analogous resonances are expected whenever the sample is a heterogeneous mixture assembled from a common building block.


Assuntos
Proteínas do Capsídeo/análise , Capsídeo/química , Espectrometria de Massas/métodos , Capsídeo/metabolismo , Vírus da Hepatite B/química , Vírus da Hepatite B/metabolismo
16.
Bioorg Med Chem Lett ; 30(14): 127262, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32527560

RESUMO

We previously reported on the monobody E1, which specifically targets the tumor marker hEphA2. In this study, we labeled NOTA-conjugated E1 with 64Cu (64Cu-NOTA-E1) and evaluated biologic characteristics. The uptake of 64Cu-NOTA-E1 in PC3 cells (a human prostate cancer cell line) with high expression of hEphA2 increased in a time-dependent manner. In PC3 xenograft mice, 64Cu-NOTA-E1 injected via the tail vein allowed visualization of tumors on positron emission tomography after 1 h and the highest uptake measured at 24 h post-injection. By contrast, the radioactivity of other tissues either did not increase or decreased over 24 h. This indicates that 64Cu-NOTA-E1 has high tumor uptake and retention, with rapid clearance, and low background values in other tissues. Therefore, 64Cu-NOTA-E1 should be suitable as a novel PET imaging agent for hEphA2-expressing tumors.


Assuntos
Anticorpos/química , Efrina-A2/genética , Tomografia por Emissão de Pósitrons , Neoplasias da Próstata/diagnóstico por imagem , Animais , Radioisótopos de Cobre , Efrina-A2/química , Compostos Heterocíclicos com 1 Anel/química , Humanos , Masculino , Camundongos , Estrutura Molecular , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Células PC-3 , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptor EphA2
17.
Bioorg Med Chem Lett ; 30(14): 127250, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32527550

RESUMO

Seedlings of natural crops are valuable sources of pharmacologically active phytochemicals. In this study, we aimed to identify new active secondary metabolites in Avena sativa L. (oat) seedlings. Two new compounds, avenafuranol (1) and diosgenoside (2), along with eight known compounds (3-10) were isolated from the A. sativa L. seedlings. Their chemical structures were elucidated via 1D and 2D NMR spectroscopy, high-resolution ESIMS, IR spectroscopy, optical rotation analysis, and comparisons with the reported literature. The effect of each isolated compound on alkaline phosphatase (ALP) activity for osteoblast differentiation induced by bone morphogenetic protein-2 (BMP-2) was investigated using the C2C12 immortal mouse myoblast cell line. Compounds 1, 4, 6, 8, and 9 induced dose-dependent increases in ALP expression relative to ALP expression in cells treated with only BMP-2, and no cytotoxicity was observed. These results suggest that A. sativa L. seedlings are a natural source of compounds that may be useful for preventing bone disorders.


Assuntos
Avena/química , Osteoblastos/efeitos dos fármacos , Animais , Avena/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Relação Dose-Resposta a Droga , Camundongos , Estrutura Molecular , Plântula/metabolismo , Relação Estrutura-Atividade
18.
Strahlenther Onkol ; 193(7): 543-551, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28492995

RESUMO

PURPOSE: To evaluate the global health status of long-term cervical cancer survivors (LCCS) who survived for more than 4 years after curative radiation treatment (RT). PATIENTS AND METHODS: Medical records of 562 women treated with RT in our institution between 2003 and 2010 were reviewed. Excluding 259 women who died of disease or were lost to follow-up, disease status and late morbidities were evaluated in 303 LCCS. Quality of life (QoL) was analyzed in 168 LCCS using a questionnaire from the European Organization for the Research and Treatment of Cancer, and the results were compared with an age-matched healthy Korean female population. RESULTS: Median follow-up was 6.8 years (range 4.1-12.5 years). There were 14 deaths (7 cancer specific) and 14 recurrences (5 local recurrences and 9 distant metastases). The median time to recurrence was 6.0 years (range 4.1-8.2 years). Grade ≥2 late toxicities were frequently observed in the bladder (19%) and small/large intestine (15%). Multivariate analysis revealed a higher rate of late toxicity in patients aged ≥51 years at diagnosis (small/large intestine: hazard ratio, HR, 2.5 [1.2-5.5]; bladder: HR 2.4 [1.3-4.5]; and bone: HR 4.3 [1.2-15.8]) than patients aged <51 years. Compared to the general population, LCCS exhibited a significantly higher rate of body image concerns, sexual dysfunction, lymphedema, and peripheral neuropathy. CONCLUSION: New recurrences occurred in 5% of LCCS and grade ≥2 treatment-related morbidities were present in 33%. A significant proportion of LCCS also showed decreased cervical-cancer-specific QoL. These results suggest the need for long-term surveillance and follow-up care for LCCS.


Assuntos
Quimiorradioterapia , Nível de Saúde , Lesões por Radiação/etiologia , Reirradiação , Sobreviventes , Neoplasias do Colo do Útero/terapia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Histerectomia , Intestinos/efeitos da radiação , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Qualidade de Vida/psicologia , Dosagem Radioterapêutica , Análise de Sobrevida , Bexiga Urinária/efeitos da radiação , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/psicologia
19.
J Neurol Neurosurg Psychiatry ; 88(8): 639-647, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28572277

RESUMO

OBJECTIVE: To analyse predictors for relapses and number of attacks under different immunotherapies in patients with neuromyelitis optica spectrum disorder (NMOSD). DESIGN: This is a retrospective cohort study conducted in neurology departments at 21 regional and university hospitals in Germany. Eligible participants were patients with aquaporin-4-antibody-positive or aquaporin-4-antibody-negative NMOSD. Main outcome measures were HRs from Cox proportional hazard regression models adjusted for centre effects, important prognostic factors and repeated treatment episodes. RESULTS: 265 treatment episodes with a mean duration of 442 days (total of 321 treatment years) in 144 patients (mean age at first attack: 40.9 years, 82.6% female, 86.1% aquaporin-4-antibody-positive) were analysed. 191 attacks occurred during any of the treatments (annual relapse rate=0.60). The most common treatments were rituximab (n=77, 111 patient-years), azathioprine (n=52, 68 patient-years), interferon-ß (n=32, 61 patient-years), mitoxantrone (n=34, 32.1 patient-years) and glatiramer acetate (n=17, 10 patient-years). Azathioprine (HR=0.4, 95% CI 0.3 to 0.7, p=0.001) and rituximab (HR=0.6, 95% CI 0.4 to 1.0, p=0.034) reduced the attack risk compared with interferon-ß, whereas mitoxantrone and glatiramer acetate did not. Patients who were aquaporin-4-antibody-positive had a higher risk of attacks (HR=2.5, 95% CI 1.3 to 5.1, p=0.009). Every decade of age was associated with a lower risk for attacks (HR=0.8, 95% CI 0.7 to 1.0, p=0.039). A previous attack under the same treatment tended to be predictive for further attacks (HR=1.5, 95% CI 1.0 to 2.4, p=0.065). CONCLUSIONS: Age, antibody status and possibly previous attacks predict further attacks in patients treated for NMOSD. Azathioprine and rituximab are superior to interferon-ß.


Assuntos
Imunoterapia/métodos , Neuromielite Óptica/tratamento farmacológico , Adulto , Aquaporina 4/imunologia , Autoanticorpos/sangue , Azatioprina/uso terapêutico , Estudos de Coortes , Feminino , Seguimentos , Alemanha , Acetato de Glatiramer/uso terapêutico , Humanos , Interferon beta/uso terapêutico , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Mitoxantrona/uso terapêutico , Neuromielite Óptica/imunologia , Prognóstico , Recidiva , Sistema de Registros , Estudos Retrospectivos , Rituximab/uso terapêutico , Resultado do Tratamento
20.
Bioorg Med Chem Lett ; 27(17): 3968-3973, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28784292

RESUMO

The biological activities of the ethanol extract from Cirsium japonicum var. maackii (ICF-1) and its major component, polyphenol cirsimaritin, were investigated as part of the search for possible alternative drugs for breast cancer. Three in vitro cell-based assays were used: the cell proliferation assay, tube-formation assay, and Western blot analysis. Both the ICF-1 extract and cirsimaritin inhibited the viability of HUVECs in a dose-dependent manner. The inhibition achieved was 36.89% at a level of 200µg/ml by the ICF-1 extract and 62.04% at a level of 100µM by cirsimaritin. The ICF-1 extract and cirsimaritin reduced tube formation by 12.69% at level of 25µg/ml and 32.18% at the levels of 6.25µM, respectively. Cirsimaritin inhibited angiogenesis by downregulation of VEGF, p-Akt and p-ERK in MDA-MB-231 cells, suggesting that cirsimaritin is potentially useful as an anti-metastatic agent. The present study demonstrated that Cirsium japonicum extract and its active component cirsimaritin is an excellent candidate as an alternative anti-breast cancer drug.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Cirsium/química , Flavonas/farmacologia , Neovascularização Patológica/tratamento farmacológico , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Flavonas/química , Flavonas/isolamento & purificação , Humanos , Estrutura Molecular , Neovascularização Patológica/patologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Relação Estrutura-Atividade
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