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1.
J Agric Food Chem ; 68(38): 10424-10431, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32172556

RESUMO

Untargeted liquid chromatography/mass spectrometry (LC/MS) flavoromics analysis was carried out on 18 coffee brews ranging in Specialty Coffee Association (SCA) cup scores. Six compounds highly predictive of low cup score were isolated from coffee using multidimensional preparative LC/MS and further evaluated by sensory recombination analysis with certified SCA quality graders. A significant decrease in cup score was demonstrated with four of the six compounds when added to a specialty coffee brew. High-resolution mass spectrometry and mono- and bidimensional nuclear magnetic resonance experiments were used to successfully elucidate four of the structures as 16α,17-dihydroxy-ent-kauran-19-oic acid (compound 1), its diglycosidic compound 16α,17-dihydroxy-ent-kauran-19-diglycoside (compound 2), 16α,17,18-trihydroxy-ent-kauran-19-oic acid (compound 5), and 16α-hydroxy-17-ent-kauren-19-oic acid (compound 6). All four ent-kaurane diterpene compounds were endogenous to green coffee beans, providing direct chemical indicators of low-quality coffee.


Assuntos
Coffea/química , Café/química , Aromatizantes/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Sementes/química
2.
J Physiol ; 598(10): 1865-1880, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32012273

RESUMO

KEY POINTS: Cation-chloride cotransporters (CCCs) play a critical role in controlling the efficacy and polarity of GABAA receptor (GABAA R)-mediated transmission in the brain, yet their expression and function in GABAergic interneurons has been overlooked. We compared the polarity of GABA signalling and the function of CCCs in mouse hippocampal pyramidal neurons and parvalbumin-expressing interneurons. Under resting conditions, GABAA R activation was mostly depolarizing and yet inhibitory in both cell types. KCC2 blockade further depolarized the reversal potential of GABAA R-mediated currents often above action potential threshold. However, during repetitive GABAA R activation, the postsynaptic response declined independently of the ion flux direction or KCC2 function, suggesting intracellular chloride build-up is not responsible for this form of plasticity. Our data demonstrate similar mechanisms of chloride regulation in mouse hippocampal pyramidal neurons and parvalbumin interneurons. ABSTRACT: Transmembrane chloride gradients govern the efficacy and polarity of GABA signalling in neurons and are usually maintained by the activity of cation-chloride cotransporters, such as KCC2 and NKCC1. Whereas their role is well established in cortical principal neurons, it remains poorly documented in GABAergic interneurons. We used complementary electrophysiological approaches to compare the effects of GABAA receptor (GABAA R) activation in adult mouse hippocampal parvalbumin interneurons (PV-INs) and pyramidal cells (PCs). Loose cell-attached, tight-seal and gramicidin-perforated patch recordings all show GABAA R-mediated transmission is slightly depolarizing and yet inhibitory in both PV-INs and PCs. Focal GABA uncaging in whole-cell recordings reveal that KCC2 and NKCC1 are functional in both PV-INs and PCs but differentially contribute to transmembrane chloride gradients in their soma and dendrites. Blocking KCC2 function depolarizes the reversal potential of GABAA R-mediated currents in PV-INs and PCs, often beyond firing threshold, showing KCC2 is essential to maintain the inhibitory effect of GABAA Rs. Finally, we show that repetitive 10 Hz activation of GABAA Rs in both PV-INs and PCs leads to a progressive decline of the postsynaptic response independently of the ion flux direction or KCC2 function. This suggests intraneuronal chloride build-up may not predominantly contribute to activity-dependent plasticity of GABAergic synapses in this frequency range. Altogether our data demonstrate similar mechanisms of chloride regulation in mouse hippocampal PV-INs and PCs and suggest KCC2 downregulation in the pathology may affect the valence of GABA signalling in both cell types.


Assuntos
Cloretos , Parvalbuminas , Animais , Cátions , Cloretos/metabolismo , Hipocampo/metabolismo , Interneurônios/metabolismo , Camundongos , Parvalbuminas/metabolismo , Receptores de GABA-A , Ácido gama-Aminobutírico
3.
Food Chem ; 301: 125250, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377616

RESUMO

Untargeted LC/MS flavoromic profiling was utilized to identify compounds that positively impact coffee quality. The chemical profiles of eighteen coffee samples and the corresponding Specialty Coffee Association (SCA) cup scores were modeled by orthogonal partial least squares (OPLS) analysis with good fit and predictive ability (R2Y > 0.9, Q2 > 0.9). Four highly predictive chemical compounds positively correlated to cup score were subsequently isolated and purified (>90%) by multi-dimensional preparative LC/MS fractionation. Sensory recombination analysis by certified SCA Q-graders (n = 5) confirmed three out of four compounds significantly increased cup score when added to a control coffee (p < 0.001). Based on accurate mass spectrometry and NMR experiments, the compound structures were identified as novel compounds 3-O-caffeoyl-4-O-3-methylbutanoylquinic acid, and the corresponding lactone 3-O-caffeoyl-4-O-3-methylbutanoyl-1,5-quinide, as well as an unknown phenolic derivative containing a 3-methylbutanoyl moiety ([M-H]-1, m/z 671). No direct flavor activity was observed for each compound, indicating these compounds act as flavor-modifiers.


Assuntos
Café/química , Qualidade dos Alimentos , Paladar , Cromatografia Líquida , Lactonas/análise , Análise dos Mínimos Quadrados , Espectrometria de Massas
4.
Mol Med Rep ; 12(1): 498-502, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25760445

RESUMO

Osteosarcoma (OS) is the most common type of malignant bone tumor. Despite aggressive multimodal treatments, including surgical resection, chemotherapy and adjunctive immunotherapies, patients with OS with high-grade malignancy have a poor five-year survival rate that has remained unchanged over the past two decades, highlighting the urgent requirement for novel therapeutic approaches. Signal transducers and activators of transcription 3 (STAT3) has been implicated as an oncogene and therapeutic target in a variety of neoplastic diseases. The aim of the present study was to determine whether inhibition of the janus kinase 2 (JAK2)/STAT3 pathway by FLLL32, a specific JAK2/STAT3 inhibitor, is able to provide a potential therapy for OS. FLLL32 inhibited OS cell growth in vitro and delayed OS growth in an OS xenograft nude mouse model. STAT3 knockdown by short hairpin RNA delayed OS formation in vivo. Thus, the JAK2/STAT3 pathway is important in OS formation. Efficacy of the FLLL32 pharmacological inhibitor in delaying OS growth suggests that targeting JAK2/STAT3 may be a potential therapeutic strategy for patients with OS.


Assuntos
Neoplasias Ósseas/genética , Janus Quinase 2/biossíntese , Osteossarcoma/genética , Fator de Transcrição STAT3/biossíntese , Animais , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Curcumina/administração & dosagem , Curcumina/análogos & derivados , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/genética , Camundongos , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Front Hum Neurosci ; 6: 292, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23125828

RESUMO

The amygdala has been repeatedly implicated in emotional processing of both positive and negative-valence stimuli. Previous studies suggest that the amygdala response to emotional stimuli is lower when the subject is in a meditative state of mindful-attention, both in beginner meditators after an 8-week meditation intervention and in expert meditators. However, the longitudinal effects of meditation training on amygdala responses have not been reported when participants are in an ordinary, non-meditative state. In this study, we investigated how 8 weeks of training in meditation affects amygdala responses to emotional stimuli in subjects when in a non-meditative state. Healthy adults with no prior meditation experience took part in 8 weeks of either Mindful Attention Training (MAT), Cognitively-Based Compassion Training (CBCT; a program based on Tibetan Buddhist compassion meditation practices), or an active control intervention. Before and after the intervention, participants underwent an fMRI experiment during which they were presented images with positive, negative, and neutral emotional valences from the IAPS database while remaining in an ordinary, non-meditative state. Using a region-of-interest analysis, we found a longitudinal decrease in right amygdala activation in the Mindful Attention group in response to positive images, and in response to images of all valences overall. In the CBCT group, we found a trend increase in right amygdala response to negative images, which was significantly correlated with a decrease in depression score. No effects or trends were observed in the control group. This finding suggests that the effects of meditation training on emotional processing might transfer to non-meditative states. This is consistent with the hypothesis that meditation training may induce learning that is not stimulus- or task-specific, but process-specific, and thereby may result in enduring changes in mental function.

6.
Invest New Drugs ; 30(3): 916-26, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21340507

RESUMO

Constitutive activation of Signal Transducers and Activators of Transcription 3 (STAT3) is frequently detected in osteosarcoma, and hence, may serve as a therapeutic target. In order to target STAT3, we tested two new STAT3 inhibitors, LLL12 and FLLL32. LLL12 and FLLL32 inhibit STAT3 phosphorylation and STAT3 downstream targets. LLL12 and FLLL32 also inhibit IL-6 induced STAT3 phosphorylation. The inhibition of STAT3 by LLL12 and FLLL32 resulted in the induction of apoptosis, reduction of plating efficiency, and migration in osteosarcoma cells. Furthermore, LLL12 and FLLL32 inhibited SJSA osteosarcoma cells and OS-33 tumor growth in murine xenografts. These results provide evidence that constitutive STAT3 signaling is required for osteosarcoma survival and migration in vitro and tumor growth in vivo. Blocking persistent STAT3 signaling by LLL12 and FLLL32 may be a novel therapeutic approach for osteosarcoma.


Assuntos
Antraquinonas/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Curcumina/análogos & derivados , Osteossarcoma/tratamento farmacológico , Fator de Transcrição STAT3/antagonistas & inibidores , Sulfonamidas/uso terapêutico , Animais , Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Curcumina/farmacologia , Curcumina/uso terapêutico , Feminino , Humanos , Interleucina-6/farmacologia , Camundongos , Camundongos Nus , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Fosforilação/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Sulfonamidas/farmacologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
BMC Cancer ; 11: 112, 2011 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-21443800

RESUMO

BACKGROUND: Curcumin is a naturally occurring phenolic compound shown to have a wide variety of antitumor activities; however, it does not attain sufficient blood levels to do so when ingested. Using structure-based design, a novel compound, FLLL32, was generated from curcumin. FLLL32 possesses superior biochemical properties and more specifically targets STAT3, a transcription factor important in tumor cell survival, proliferation, metastasis, and chemotherapy resistance. In our previous work, we found that several canine and human osteosarcoma (OSA) cell lines, but not normal osteoblasts, exhibit constitutive phosphorylation of STAT3. Compared to curcumin, we hypothesized that FLLL32 would be more efficient at inhibiting STAT3 function in OSA cells and that this would result in enhanced downregulation of STAT3 transcriptional targets and subsequent death of OSA cells. METHODS: Human and canine OSA cells were treated with vehicle, curcumin, or FLLL32 and the effects on proliferation (CyQUANT®), apoptosis (SensoLyte® Homogeneous AMC Caspase- 3/7 Assay kit, western blotting), STAT3 DNA binding (EMSA), and vascular endothelial growth factor (VEGF), survivin, and matrix metalloproteinase-2 (MMP2) expression (RT-PCR, western blotting) were measured. STAT3 expression was measured by RT-PCR, qRT- PCR, and western blotting. RESULTS: Our data showed that FLLL32 decreased STAT3 DNA binding by EMSA. FLLL32 promoted loss of cell proliferation at lower concentrations than curcumin leading to caspase-3- dependent apoptosis, as evidenced by PARP cleavage and increased caspase 3/7 activity; this could be inhibited by treatment with the pan-caspase inhibitor Z-VAD-FMK. Treatment of OSA cells with FLLL32 decreased expression of survivin, VEGF, and MMP2 at both mRNA and protein levels with concurrent decreases in phosphorylated and total STAT3; this loss of total STAT3 occurred, in part, via the ubiquitin-proteasome pathway. CONCLUSIONS: These data demonstrate that the novel curcumin analog FLLL32 has biologic activity against OSA cell lines through inhibition of STAT3 function and expression. Future work with FLLL32 will define the therapeutic potential of this compound in vivo.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Ósseas/patologia , Curcumina/análogos & derivados , DNA/metabolismo , Osteossarcoma/patologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Animais , Apoptose/genética , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Curcumina/farmacologia , Doenças do Cão/genética , Doenças do Cão/patologia , Cães , Avaliação Pré-Clínica de Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Osteossarcoma/genética , Ligação Proteica/efeitos dos fármacos
8.
Stud Health Technol Inform ; 129(Pt 1): 285-90, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17911724

RESUMO

Patient safety efforts advocate for transforming healthcare from a culture of blame to a non-punitive "culture of safety." One of the most challenging hurdles is to encourage healthcare practitioners to be mindful about their activities. To promote mindfulness during clinical education for entry-level nurses, we developed a web-based dangerous situation and near miss reporting system for a cohort of baccalaureate nursing students (N=156). For this curricular innovation project, we provided wireless handheld devices to students who were required to submit one report for each of their clinical days in the medical-surgical, pediatric, psychiatric, obstetrics and community settings. During a ten-week period, students submitted 1487 reports. Of these, 63% were dangerous situations and 37% were near misses. The most frequently occurring dangerous situations were poor infection control practices. The most commonly reported near misses were medication errors. Free text comments from students identified inadequate patient identification and poor documentation as commonly occurring dangerous situations observed.


Assuntos
Bacharelado em Enfermagem , Erros Médicos/prevenção & controle , Gestão da Segurança/métodos , Humanos , Garantia da Qualidade dos Cuidados de Saúde
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