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1.
Br J Cancer ; 131(8): 1387-1398, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39266624

RESUMO

BACKGROUND: Temozolomide (TMZ) is the first-line chemotherapeutic drug for gliomas treatment. However, the clinical efficacy of TMZ in glioma patients was very limited. Therefore, it is urgently needed to discover a novel approach to increase the sensitivity of glioma cells to TMZ. METHODS: Western blot, immunohistochemical staining, and qRT-PCR assays were used to explore the mechanisms underlying TMZ promoting DKK1 expression and andrographolide (AND) inhibiting DKK1 expression. HPLC was used to detect the ability of andrographolide (AND) to penetrate the blood-brain barrier. MTT assay, bioluminescence images, magnetic resonance imaging (MRI) and H&E staining were employed to measure the proliferative activity of glioma cells and the growth of intracranial tumors. RESULTS: TMZ can promote DKK1 expression in glioma cells and brain tumors of an orthotopic model of glioma. DKK1 could promote glioma cell proliferation and tumor growth in an orthotopic model of glioma. Mechanistically, TMZ increased EGFR expression and subsequently induced the activation of its downstream MEK-ERK and PI3K-Akt pathways, thereby promoting DKK1 expression in glioma cells. Andrographolide inhibited TMZ-induced DKK1 expression through inactivating MEK-ERK and PI3K-Akt pathways. Andrographolide can cross the blood-brain barrier, the combination of TMZ and andrographolide not only improved the anti-tumor effects of TMZ but also showed a survival benefit in an orthotopic model of glioma. CONCLUSION: Andrographolide can enhance anti-tumor activity of TMZ against glioma by inhibiting DKK1 expression.


Assuntos
Antineoplásicos Alquilantes , Neoplasias Encefálicas , Proliferação de Células , Diterpenos , Glioma , Peptídeos e Proteínas de Sinalização Intercelular , Temozolomida , Diterpenos/farmacologia , Diterpenos/uso terapêutico , Temozolomida/farmacologia , Glioma/tratamento farmacológico , Glioma/patologia , Glioma/genética , Glioma/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Humanos , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Camundongos , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Camundongos Nus , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sinergismo Farmacológico , Receptores ErbB/genética , Receptores ErbB/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
2.
Biomed Chromatogr ; 38(3): e5795, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38071756

RESUMO

Following the highly successful Chinese American Society for Mass Spectrometry (CASMS) conferences in the previous 2 years, the 3rd CASMS Conference was held virtually on August 28-31, 2023, using the Gather.Town platform to bring together scientists in the MS field. The conference offered a 4-day agenda with a scientific program consisting of two plenary lectures, and 14 parallel symposia in which a total of 70 speakers presented technological innovations and their applications in proteomics and biological MS and metabo-lipidomics and pharmaceutical MS. In addition, 16 invited speakers/panelists presented at two research-focused and three career development workshops. Moreover, 86 posters, 12 lightning talks, 3 sponsored workshops, and 11 exhibitions were presented, from which 9 poster awards and 2 lightning talk awards were selected. Furthermore, the conference featured four young investigator awardees to highlight early-career achievements in MS from our society. The conference provided a unique scientific platform for young scientists (i.e. graduate students, postdocs, and junior faculty/investigators) to present their research, meet with prominent scientists, learn about career development, and job opportunities (http://casms.org).


Assuntos
Espectrometria de Massas , Lipidômica , Preparações Farmacêuticas , Proteômica , Congressos como Assunto
3.
Nano Lett ; 23(15): 7197-7205, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37506224

RESUMO

Nanobio interaction studies have generated a significant amount of data. An important next step is to organize the data and design computational techniques to analyze the nanobio interactions. Here we developed a computational technique to correlate the nanoparticle spatial distribution within heterogeneous solid tumors. This approach led to greater than 88% predictive accuracy of nanoparticle location within a tumor tissue. This proof-of-concept study shows that tumor heterogeneity might be defined computationally by the patterns of biological structures within the tissue, enabling the identification of tumor patterns for nanoparticle accumulation.


Assuntos
Nanopartículas , Neoplasias , Humanos , Nanopartículas/química
4.
Int Wound J ; 21(3): e14715, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38494179

RESUMO

To systematically explore the effects of minimally invasive plate osteosynthesis (MIPO) versus intramedullary nail (IMN) on wound infection and wound healing in patients with distal tibia fractures. A computerised search of PubMed, Web of Science, Cochrane Library, Embase, Wanfang, China Biomedical Literature Database (CBM) and China National Knowledge Infrastructure databases was performed, from their inception to October 2023, to identify relevant studies on the application of MIPO and IMN in patients with distal tibial fractures. The quality of the included literature was evaluated by two researchers based on inclusion and exclusion criteria, and basic information of the literature was collected, with wound infection, postoperative complications and wound healing time as the main indicators for analysis. Stata 17.0 software was applied for analysis. Overall, 23 papers and 2099 patients were included, including 1026 patients in the MIPO group and 1073 patients in the IMN group. The results revealed, when compared with IMN treatment, patients with distal tibia fractures who underwent MIPO treatment had a lower incidence of postoperative complications (OR = 0.33, 95% CI: 0.25-0.42, p < 0.001) and a shorter wound healing time (SMD = -1.00, 95% CI: -1.51 to -0.49, p < 0.001), but the incidence of postoperative wound infection was higher (OR = 2.01, 95% CI: 1.35-3.01, p = 0.001). Both MIPO and IMN are excellent treatments for distal tibia fractures. MIPO is effective in reducing the incidence of complications as well as shortening the time of wound healing time but increases the risk of wound infection. In clinical practice, surgeons can make individual choices based on the patient's wishes and proficiency in both techniques.


Assuntos
Fraturas do Tornozelo , Fixação Intramedular de Fraturas , Fraturas da Tíbia , Humanos , Fixação Intramedular de Fraturas/métodos , Consolidação da Fratura , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fixação Interna de Fraturas/efeitos adversos , Fraturas da Tíbia/cirurgia , Infecção da Ferida Cirúrgica/etiologia , Resultado do Tratamento
5.
Rapid Commun Mass Spectrom ; 36(22): e9377, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-35940586

RESUMO

RATIONALE: The in-sample calibration curve (ISCC) approach of quantification utilizes the response of isotopologue ions from spiked-in stable isotope labeled internal standard (SIL-IS) to build a standard curve. The quantitative analysis of the study sample is achieved based on the response of selected monoisotopic analyte ion against the calibration curve. Although this methodology has been demonstrated to be feasible by unit and high-resolution mass spectrometers, quantitation on high-resolution mass spectrometer with product ions has not been tested. We tested the feasibility of this approach using product ions on an high-resolution mass spectrometer equipped with an Orbitrap detector. METHODS: Using a proteomics workflow for sample preparation, two surrogate peptides were quantified from a complex matrix of protein digest from human peripheral blood mononuclear cells (hPBMCs). SIL-IS was spiked in at different levels to construct calibration curves in a traditional manner. ISCCs were prepared using extracted ion chromatograms from isotopically resolved mass spectra and compared with traditional calibration curves. RESULTS: A linear response was observed with ISCC approach for at least two to three orders of magnitude in MS1 as well as targeted MS2 (tMS2). From protein digests, isobaric interferences were observed for endogenous peptides on the MS1 level; this was circumvented with product-ion-based quantitation where for one peptide, %CV for endogenous levels was more than 20% with ISCC but higher with the traditional calibration curve approach. For the second peptide, endogenous levels could not be determined in the traditional approach as calibrant levels did not bracket the lower end, and with the ISCC approach, isotopologues at abundances lower than the endogenous level allowed for quantitative assessments. CONCLUSIONS: ISCC demonstrated improved precision across surrogate peptides from endogenous protein digests. In samples where endogenous analyte concentrations were low in abundance, ISCC rescued what would have been a non-reportable result in a traditional bioanalytical assay as calibrant levels were not prepared at adequately low levels to bracket unknowns. ISCC using high-resolution mass spectrometer is feasible and ideal compared to unit resolution mass spectrometers. High-resolution mass spectrometer allows for isotopic resolution for analytes with > + 2 charge state and provides flexibility in quantification using multiple product ions. ISCC using high-resolution mass spectrometer allows for simultaneous assaying of low abundance isotopologues, the signal acquisition of which is not constrained by limits in data acquisition or calibrant preparation as with other approaches but rather limited by platform sensitivity. In contrast to unit resolution mass spectrometers, these features offered by high-resolution mass spectrometer could be especially useful for the drug discovery assay support where there is less lead time for assay development than for the assays to support the drug development studies.


Assuntos
Leucócitos Mononucleares , Espectrometria de Massas em Tandem , Calibragem , Humanos , Isótopos , Peptídeos , Espectrometria de Massas em Tandem/métodos
6.
BMC Endocr Disord ; 22(1): 55, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35255870

RESUMO

BACKGROUND: The study was aimed at investigating the potential role of chronic lymphocytic thyroiditis (CLT) in papillary thyroid cancer (PTC) aggressiveness for patients aged below 55, as well as to figure out factors influencing potential recurrence risk in different age groups. METHODS: A total of 635 adult patients were retrospectively analyzed. 188 patients were diagnosed with coexistent CLT and the remaining 447 were classified as non-CLT. Then the characteristics of CLT-coexisted patients and non-CLT ones were compared respectively when patients were aged ≥ 55 years or below. The association among postoperative clinicopathological features were also analyzed using multivariate regression. In addition, the prognostic value of several variables relating to high-risk recurrence were estimated within different age groups. RESULTS: When divided in two age groups (55 years as the borderline), non-CLT group (aged below 55 years) had a remarkable frequency of small size lesion (Dmax ≤ 1 cm) compared with CLT-coexisted patients (54.6% to 43.0%, p = 0.02). In addition, non-CLT patients tended to have intrathyroidal extension as opposed to those with coexistent CLT (20.2% to 28.2%, p = 0.05). In multivariate analysis, CLT still significantly acted as an independent risk factor of greater lesion size (Dmin > 1 cm) (OR = 1.7, p = 0.02) and mildly promoted gross extrathyroidal extension (ETE) (OR = 1.4, p = 0.06). However, associations didn't emerge in the characteristics mentioned above with CLT when patients were ≥ 55 years old. The prognostic value of CLT in high-risk recurrence was evident only in patients aged 35-44 years. (OR = 2.4, 95%CI:1.2-5.4, p = 0.02). Greater lesion size independently promoted gross ETE, no matter patients were aged above 55 years or not. Its prognostic value of high-risk recurrence was significant throughout all age groups. CONCLUSION: These findings revealed that CLT coexistence might be the unfavorable factor of PTC aggressiveness in patients aged below 55 years. Its role as well as greater tumor size may potentially predict higher recurrence risk according to results figured out in the prediction model.


Assuntos
Doença de Hashimoto/patologia , Recidiva Local de Neoplasia/patologia , Câncer Papilífero da Tireoide/patologia , Adulto , Fatores Etários , Idoso , China/epidemiologia , Feminino , Doença de Hashimoto/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Câncer Papilífero da Tireoide/complicações
7.
FASEB J ; 34(4): 5178-5192, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32061112

RESUMO

Hepatic fibrosis occurs during chronic hepatic injury and is involved in hepatic stellate cells (HSCs) activated by several types of immune cells. Among the immune cells, hepatic macrophages and their crosstalk with HSCs play a vital role in all stages of hepatic fibrosis. Exosomes, which are 30-150 nm lipid bilayer vehicles, can transfer specific lipid, nucleic acids, proteins, and other bioactive molecules. Exosomes can act as good communication between macrophages and HSCs. Herein, we investigated the role of exosomes between THP-1 macrophage and HSCs in the progression of liver fibrosis. Exosomes originating from lipopolysaccharide (LPS)-treated THP-1 macrophages promoted HSCs proliferation and induced the increased expression of fibrotic genes. LPS could alter the miRNA profile in exosomes secreted from THP-1 macrophages. The changed miR-103-3p in exosomes could promote HSCs proliferation and activation by targeting Krüppel-like factor 4 (KLF4) and it plays important roles in the crosstalk between THP-1 macrophages and HSCs during the progression of liver fibrosis. Moreover, miR-103-3p in serum exosomes from liver fibrosis patients could be a biomarker for liver fibrosis. Therefore, exosomes may have important roles in the crosstalk between macrophage and HSCs in the progression of chronic liver diseases.


Assuntos
Exossomos/genética , Células Estreladas do Fígado/patologia , Lipopolissacarídeos/efeitos adversos , Cirrose Hepática/patologia , Macrófagos/patologia , MicroRNAs/genética , Biomarcadores/sangue , Estudos de Casos e Controles , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , MicroRNAs/sangue , Transdução de Sinais
8.
J Nat Prod ; 84(7): 1954-1966, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34170694

RESUMO

Cdc37 associates kinase clients to Hsp90 and promotes the development of cancers. Celastrol, a natural friedelane triterpenoid, can disrupt the Hsp90-Cdc37 interaction to provide antitumor effects. In this study, 31 new celastrol derivatives, 2a-2d, 3a-3g, and 4a-4t, were designed and synthesized, and their Hsp90-Cdc37 disruption activities and antiproliferative activities against cancer cells were evaluated. Among these compounds, 4f, with the highest tumor cell selectivity (15.4-fold), potent Hsp90-Cdc37 disruption activity (IC50 = 1.9 µM), and antiproliferative activity against MDA-MB-231 cells (IC50 = 0.2 µM), was selected as the lead compound. Further studies demonstrated 4f has strong antitumor activities both in vitro and in vivo through disrupting the Hsp90-Cdc37 interaction and inhibiting angiogenesis. In addition, 4f exhibited less toxicity than celastrol and showed a good pharmacokinetics profile in vivo. These findings suggest that 4f may be a promising candidate for development of new cancer therapies.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Chaperoninas/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Triterpenos Pentacíclicos/farmacologia , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos Nus , Simulação de Acoplamento Molecular , Estrutura Molecular , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra
9.
J Clean Prod ; 307: 1-8, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34924700

RESUMO

Few studies have investigated the performance of anaerobic digestion (AD) to convert animal and agro-industrial wastes to organic fertilizers over a long-term field conditions. This paper studied three large-scale mesophilic digesters (D1eD3) over two years for their effects on feedstocks, which were dairy manure for D1 and D2 and co-digestion mixed manure and agro-industrial wastes for D3. Hydraulic retention times (HRT) were 9 d for D1, 12 d for D2, and 34 d for D3. Digester influent and effluent samples were taken every two months from the digesters and analyzed for pH, and concentrations of total solids (TS), ammonium nitrogen (NH4-N), total Kjeldahl nitrogen (TKN), total phosphorus (TP), and eight metals. The study revealed high variability in converting feedstock in the three digesters. Compared with their respective influent, the mean digester effluent pH decreased from 7.9 by 0.6 in D1 (p < 0.01) and by 0.3 in D2 (p < 0.01), but it increased from 6.1 by 1.8 in D3 (p < 0.01). The mean digester effluent TS increased from 3.4% by 0.1% (p > 0.05) in D1, but it decreased from 4.9% by 1.3% in D2 (p < 0.05) and from 12.3% by 4.8% in D3 (p < 0.01). All three digesters significantly increased NH4-N concentrations by 21.4 e81.8% (p < 0.05), but insignificantly changed TKN and TP concentrations (p > 0.05). Effects of AD on all metal concentrations were mixed and were insignificant (p > 0.05) because of large concentration variations. However, study of a ratio quotient (q Mg ) using magnesium (Mg) as the reference discovered accumulation of NH4-N, copper, potassium, and sodium, but loss of TKN, TP, iron, manganese, zinc, and calcium during AD for D2 and D3. The impact of AD conversion was closely related with types of feedstock (on pH) and HRT (on TS and NH4-N). The results of this study can assist in developing strategies for cleaner production using AD in an environmentally sustainable manner.

10.
Org Biomol Chem ; 18(6): 1135-1139, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-31967630

RESUMO

Biomimetic total syntheses of baefrutones A-D (1-4), baeckenon B (5), and frutescones A, D-F (6-9), isolated from the leaves of Baeckea frutescens, were achieved in 9, 8, and 5 steps, respectively, in moderate to good yields (72-83%). The synthetic routes feature the Michael addition, oxidative [4 + 2] cycloaddition, and water-promoted Diels-Alder click reactions as the key steps. This study helped gain thorough mechanistic insights into the biosynthetic origins and provided a facile approach for the construction of a library of natural tasmanone-based meroterpenoid analogues. Moreover, compounds 1-9 show potent inhibitory effects against S. paratyphi and/or C. albicans with MIC values of 3.125-25 µg mL-1, and they could be promising lead molecules for the design of new antibiotic agents.


Assuntos
Materiais Biomiméticos/farmacologia , Monoterpenos/farmacologia , Terpenos/farmacologia , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/química , Candida albicans/efeitos dos fármacos , Reação de Cicloadição , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Monoterpenos/síntese química , Monoterpenos/química , Oxirredução , Pseudomonas aeruginosa/efeitos dos fármacos , Salmonella/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade , Terpenos/síntese química , Terpenos/química
11.
J Am Chem Soc ; 141(5): 2111-2121, 2019 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30615836

RESUMO

A porous hydrogen-bonded organic framework (HOF) responsive to acid was constructed from a hexaazatrinaphthylene derivative with carboxyphenyl groups (CPHATN). Precise structures of both 1,2,4-trichlorobenzene solvate [CPHATN-1(TCB)] and activated HOF with permanent porosity (CPHATN-1a) were successfully determined by single-crystalline X-ray diffraction analysis. Permanent porosity of CPHATN-1a was evaluated by gas sorption experiments at low temperature. CPHATN-1a also shows significant thermal stability up to 633 K. Its crystals exhibit a rich photochemistry thanks to intramolecular charge-transfer and interunit proton-transfer reactions. Femtosecond (fs) experiments on crystals demonstrate that these events occur in ≤200 fs and 1.2 ps, respectively. Moreover, single-crystal fluorescence microscopy reveals a shift of the emission spectra most probably as a result of defects and a high anisotropic behavior, reflecting an ordered crystalline structure with a preferential orientation of the molecular dipole moments. Remarkably, CPHATN-1a, as a result of the protonation of pyradyl nitrogen atoms embedded in its π-conjugated core, shows reversible vapor acid-induced color changes from yellow to reddish-brown, which can be also followed by an ON/OFF of its emission. To the best of our knowledge, this is the first HOF that exhibits acid-responsive color changes. The present work provides new findings for developing stimuli responsive HOFs.

12.
New Phytol ; 224(3): 1133-1141, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31032938

RESUMO

Water-mediated fertilization is ubiquitous in early land plants. This ancestral mode of fertilization has, however, generally been considered to have been lost during the evolutionary history of terrestrial flowering plants. We investigated reproductive mechanisms in the subtropical ginger Cautleya gracilis (Zingiberaceae), which has two pollen conditions - granular and filiform masses - depending on external conditions. We tested whether rain transformed granular pollen into filiform masses and whether this then promoted pollen-tube growth and fertilization of ovules. Using experimental manipulations in the field we investigated the contribution of water-mediated fertilization to seed production. Rain caused granular pollen to form filiform masses of germinating pollen tubes, which transported sperm to ovules, resulting in fertilization and seed set. Flowers exposed to rain produced significantly more seeds than those protected from the rain, which retained granular pollen. Insect pollination made only a limited contribution to seed set because rainy conditions limited pollinator service. Our results reveal a previously undescribed fertilization mechanism in flowering plants involving water-mediated fertilization stimulated by rain. Water-mediated fertilization is likely to be adaptive in the subtropical monsoon environments in which C. gracilis occurs by ensuring reproductive assurance when persistent rain prevents insect-mediated pollination.


Assuntos
Fertilização/fisiologia , Água , Zingiberaceae/fisiologia , Animais , Abelhas/fisiologia , Flores/fisiologia , Germinação/fisiologia , Modelos Lineares , Polinização , Chuva , Sementes/fisiologia , Autofertilização
14.
J Nat Prod ; 82(12): 3267-3278, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31738062

RESUMO

Psiguadiols A-J (1-10), new meroterpenoids with rearranged skeletons, were isolated from the leaves of Psidium guajava. Compounds 1-3 represent the first examples of 6,8-diformyl-5,7-dihydroxy-4-phenylchromane-coupled sesquiterpenoids with an unprecedented C-8-spiro-fused 6/6/9/4 tetracyclic ring system. Compounds 4 and 5 represent two unusual scaffolds featuring 1ß,6ß- and 3α,5α-epoxy rings, respectively. The combination of spectroscopic data analyses, comparison of experimental and calculated ECD data, and single-crystal X-ray diffraction data of 1, 6, and 8 allowed for the assignment of the structures. A putative biosynthetic pathway for 1-10 is discussed. Compounds 1, 7, and 8 exhibited inhibitory activities against PTP1B with IC50 values of 4.7, 6.2, and 9.2 µM, respectively. In addition, molecular docking was performed to investigate the mechanism of action.


Assuntos
Inibidores Enzimáticos/farmacologia , Monoterpenos/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Psidium/química , Cristalografia por Raios X , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Humanos , Monoterpenos/química , Monoterpenos/isolamento & purificação , Análise Espectral/métodos
15.
J Nat Prod ; 82(4): 859-869, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30848923

RESUMO

Five new phloroglucinol derivatives, eucalyptins C-G (1-5), together with 13 known analogues (6-18) were isolated from the fruits of Eucalyptus globulus. The structures and absolute configurations of 1-5 were established by means of spectroscopic data analysis, computational calculation methods, and single-crystal X-ray diffraction. Compounds 1-18 were investigated for their immunosuppressive effects in vitro, and 1, 2, 6, and 7 displayed moderate inhibitory activities with IC50 values of 11.8, 10.2, 18.2, and 19.1 µM, respectively. The stimulation index (SI) of 1 was 64.2 and was compared to that of cyclosporine A (SI = 149.57). Further study demonstrated that 1 exhibited an immunosuppressive effect through inducing apoptosis and inhibiting cytokine secretion.


Assuntos
Eucalyptus/química , Imunossupressores/farmacologia , Floroglucinol/farmacologia , Animais , Células Cultivadas , Cristalografia por Raios X , Citocinas/metabolismo , Humanos , Imunossupressores/química , Concentração Inibidora 50 , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Floroglucinol/química
16.
Langmuir ; 34(1): 191-197, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29256617

RESUMO

Autofluorescent bovine serum albumin (BSA) hydrogel microspheres were prepared through the spray-drying of glutaraldehyde cross-linked BSA nanoparticles and then used for a proteinase K based degradation study in an aqueous solution. Experimental results and empirical models are presented to characterize the kinetics of BSA hydrogel microsphere degradation, as well as the accompanying release of synthesized fluorophore. The BSA gel degradation dynamics is primarily controlled by the concentration of proteinase K within the Tris buffer. The coupling of swelling dynamics and the transient distributions of fluorophore are traced by confocal microscopy. Models are developed based on the linear theory of elastic deformation coupled to enzyme and fluorophore transport. This study represents a fundamental investigation of the degradation and release kinetics of protein-based materials, which can potentially be applied for the dynamic and photostable tracking of relevant in vivo systems.


Assuntos
Endopeptidase K/metabolismo , Corantes Fluorescentes/química , Microesferas , Proteólise , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Animais , Bovinos , Glutaral/química , Hidrogéis/química , Modelos Moleculares , Conformação Proteica
17.
Org Biomol Chem ; 16(44): 8513-8524, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30357224

RESUMO

Baefrutones A-F (1-6), six new meroterpenoids with rare triketone-phloroglucinol-monoterpene/sesquiterpene frameworks, together with their biosynthetically related intermediate (±)-baeckenon B (7), were isolated from the aerial part of Baeckea frutescens under the guidance of HPLC-Q/TOF-MS2 investigation. Compounds 1-4 represent the first examples of natural meroterpenoids existing as four pairs of inseparable diastereomeric atropisomers (2 : 1, 1H NMR integration) caused by the restricted rotation around the C-6-C-7-C-1' bonds arising from the intramolecular hydrogen bond between C-1 carbonyl and 2'-OH. The discovery of these architectures not only largely enriched the chemodiversity of the meroterpenoid and atropisomer library, but also might be exciting and challenging for asymmetric organic synthesis. Their structures and absolute configurations were established by extensive spectroscopic analysis, X-ray diffraction, and ECD calculations. Compounds 5 and 6 were biomimetically synthesized from 7 and ß-caryophyllene via a regioselective oxidative hetero-Diels-Alder reaction, thus providing access to the construction of the 6/6/9/4 tetracyclic ring system. The anti-inflammatory activities of these meroterpenoids were also discussed.

18.
Fish Physiol Biochem ; 44(4): 1019-1026, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29725939

RESUMO

Cytochrome P450 enzymes (CYP enzymes) catalyze important metabolic reactions of exogenous and endogenous substrates, including fatty acid. In this study, we cloned the complete CDS of the cytochrome P450 2AA (CYP2AA) gene from the grass carp (Ctenopharyngodon idella) for the first time. CYP2AA consisted of 1500 bp, which encoded a predicted protein of 499 amino acids. The identities of CYP2AA between C. idella and zebrafish were 86%. It consists of the conserved heme-binding motif FXXGXXXCXG. Quantitative real-time PCR analysis indicated that CYP2AA mRNA in C. idella was highly expressed in liver and adipose tissue. The effects of fish oil and lard oil in diets on expression of CYP2AA mRNA in vivo were also investigated. The fish oil (FO) group exhibited significantly higher CYP2AA expression in adipose tissue than the lard oil (LO) group (P < 0.01), whereas the mRNA expression of CYP2AA was not notably different in liver. It suggested that the high abundance of CYP2AA mRNA expression in adipose tissue could be induced by fish oil. Our findings provided molecular characterization and expression profile of CYP2AA, and enhanced our understanding of CYP2AA in fish lipid metabolism.


Assuntos
Carpas/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Dieta , Proteínas de Peixes/genética , Transcriptoma , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Sequência de Bases , Carpas/crescimento & desenvolvimento , Clonagem Molecular , Gorduras na Dieta/administração & dosagem , Óleos de Peixe/administração & dosagem , Regulação da Expressão Gênica , Fígado/efeitos dos fármacos , Fígado/metabolismo , Especificidade de Órgãos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homologia de Sequência
19.
J Org Chem ; 82(3): 1448-1457, 2017 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-28029250

RESUMO

Frutescone A-G [(1-6), (+)-7, (-)-7], a new group of naturally occurring tasmanone-based meroterpenoids, were isolated from the aerial parts of Baeckea frutescens L. Compounds 1 and 4 featured a rare carbon skeleton with an unprecedented oxa-spiro[5.8] tetradecadiene ring system, existing as two favored equilibrating conformers in CDCl3 solution, identified by variable-temperature NMR. The regioselective syntheses of 4-7 were achieved in a concise manner by a biomimetically inspired key hetero-Diels-Alder reaction "on water". Compounds 1, 4, and 5 exhibited moderate cytotoxicities in vitro.


Assuntos
Myrtaceae/química , Componentes Aéreos da Planta/química , Terpenos/isolamento & purificação , Estrutura Molecular , Estereoisomerismo , Terpenos/química
20.
BMC Infect Dis ; 17(1): 463, 2017 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-28673256

RESUMO

BACKGROUND: Cryptococcal infection has become a public health challenge globally. However, information about cryptococcal infection in patients with hematological diseases remains relatively rare. METHODS: HIV-uninfected cryptococcosis cases with hematological diseases admitted to Huashan Hospital from January 2001 to December 2014 were reviewed. RESULTS: In total, 33 cryptococcosis patients were enrolled, including 12 malignant and 21 non-malignant hematological cases. Twenty-six patients had central nervous system (CNS) involvement, which was observed more often in patients with non-malignancies than with malignancies (20/21 vs. 6/12, P = 0.001) Most patients (25/26) with CNS infection were confirmed by cerebrospinal fluid (CSF) culture or smear, and 100% (20/20) of them tested positive for the CSF cryptococcal antigen test. Eighteen out of 26 cryptococcal meningitis patients were treated with amphotericin B (AmB)-based therapy, 16 of them with AmB deoxycholate (d-AmB) and 2 patients with liposomal AmB. The clinical success rate was 55.6%. D-AmB was well-tolerated at 0.35-0.59 mg/kg/d (median 0.43 mg/kg/d) and only 12 patients had mild adverse events. CONCLUSIONS: CNS cryptococcal infection was more frequent in patients with hematological non-malignancies, and cryptococcal antigen test as well as the CSF fungal culture or smear are suggested for early diagnosis. D-AmB could be used as an alternative therapy for CNS-infected patients with hematological diseases.


Assuntos
Antifúngicos/uso terapêutico , Criptococose/etiologia , Doenças Hematológicas/microbiologia , Adolescente , Adulto , Idoso , Anfotericina B/uso terapêutico , Infecções Fúngicas do Sistema Nervoso Central/tratamento farmacológico , Infecções Fúngicas do Sistema Nervoso Central/microbiologia , Criptococose/tratamento farmacológico , Ácido Desoxicólico/uso terapêutico , Combinação de Medicamentos , Feminino , Doenças Hematológicas/complicações , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/microbiologia , Humanos , Masculino , Meningite Criptocócica/tratamento farmacológico , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Centros de Atenção Terciária , Adulto Jovem
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