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1.
Int J Mol Sci ; 25(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38473763

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by the gradual loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc), resulting in reduced dopamine levels in the striatum and eventual onset of motor symptoms. Linalool (3,7-dimethyl-1,6-octadien-3-ol) is a monoterpene in aromatic plants exhibiting antioxidant, antidepressant, and anti-anxiety properties. The objective of this study is to evaluate the neuroprotective impacts of linalool on dopaminergic SH-SY5Y cells, primary mesencephalic and cortical neurons treated with 1-methyl-4-phenylpyridinium ion (MPP+), as well as in PD-like mice induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Cell viability, α-tubulin staining, western blotting, immunohistochemistry and behavioral experiments were performed. In MPP+-treated SH-SY5Y cells, linalool increased cell viability, reduced neurite retraction, enhanced antioxidant defense by downregulation of apoptosis signaling (B-cell lymphoma 2 (Bcl-2), cleaved caspase-3 and poly ADP-ribose polymerase (PARP)) and phagocyte NADPH oxidase (gp91phox), as well as upregulation of neurotrophic signaling (brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF)) and nuclear factor-erythroid 2 related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. In MPP+-treated primary mesencephalic neurons, linalool enhanced the expressions of tyrosine hydroxylase (TH), Sirtuin 1 (SirT1), and parkin. In MPP+-treated primary cortical neurons, linalool upregulated protein expression of SirT1, γ-Aminobutyric acid type A-α1 (GABAA-α1), and γ-Aminobutyric acid type B (GABAB). In PD-like mice, linalool attenuated the loss of dopamine neurons in SNpc. Linalool improved the motor and nonmotor behavioral deficits and muscle strength of PD-like mice. These findings suggest that linalool potentially protects dopaminergic neurons and improves the impairment symptoms of PD.


Assuntos
Monoterpenos Acíclicos , Neuroblastoma , Fármacos Neuroprotetores , Doença de Parkinson , Humanos , Camundongos , Animais , Doença de Parkinson/metabolismo , Neurônios Dopaminérgicos/metabolismo , Antioxidantes/metabolismo , Odorantes , Sirtuína 1/metabolismo , Fármacos Neuroprotetores/farmacologia , Neuroblastoma/metabolismo , 1-Metil-4-fenilpiridínio , Força Muscular , Modelos Teóricos , Ácido gama-Aminobutírico/metabolismo
2.
Curr Issues Mol Biol ; 45(6): 4908-4922, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37367061

RESUMO

BACKGROUND/AIM: Colorectal cancer (CRC) is the third most common cancer with a high mortality rate worldwide. Although gallic acid and hesperidin exert anticancer activity, synergistic effects of gallic acid and hesperidin against CRC remain elusive. This study aims to investigate the therapeutic mechanism of a novel combination of gallic acid and hesperidin against CRC cell growth, including cell viability, cell-cycle-associated proteins, spheroid formation, and stemness. METHODS: Gallic acid and hesperidin derived from Hakka pomelo tea (HPT) were detected by colorimetric methods and high-performance liquid chromatography using ethyl acetate as an extraction medium. CRC cell lines (HT-29 and HCT-116) treated with the combined extract were investigated in our study for cell viability (trypan blue or soft agar colony formation assay), cell cycle (propidium iodide staining), cell-cycle-associated proteins (immunoblotting), and stem cell markers (immunohistochemistry staining). RESULTS: Compared with other extraction methods, HPT extraction using an ethyl acetate medium exerts the most potent effect on inhibiting HT-29 cell growth in a dose-dependent manner. Furthermore, the treatment with combined extract had a higher inhibitory effect on CRC cell viability than gallic acid or hesperidin alone. The underlying mechanism was involved in G1-phase arrest and Cip1/p21 upregulation that could attenuate HCT-116 cell proliferation (Ki-67), stemness (CD-133), and spheroid growth in a 3D formation assay mimicking in vivo tumorigenesis. CONCLUSION: Gallic acid and hesperidin exert synergistic effects on cell growth, spheroids, and stemness of CRC and may serve as a potential chemopreventive agent. Further testing for the safety and effectiveness of the combined extract in large-scale randomized trials is required.

3.
Curr Issues Mol Biol ; 44(9): 3980-4000, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36135185

RESUMO

Polyphenols and flavonoids from non-fermented green tea and fully-fermented black tea exhibit antioxidant abilities that function as natural health foods for daily consumption. Nonetheless, evidence regarding prophylactic effects of purple shoot tea on immunomodulation remains scarce. We compared the immunomodulatory effects of different tea processes on oxidative stress and cytokine expressions in lipopolysaccharide (LPS)-stimulated macrophages. Major constituents of four tea products, Taiwan Tea Experiment Station No.12 (TTES No. 12) black and green tea and purple shoot black and purple shoot green tea (TB, TG, PB and PG, respectively), were analyzed to explore the prophylactic effects on expressions of free radicals, nitric oxide (NO), monocyte chemoattractant protein-1 (MCP-1), interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) in LPS-activated RAW264.7 cell models. PG contained abundant levels of total polyphenols, flavonoids, condensed tannins and proanthocyanidins (371.28 ± 3.83; 86.37 ± 1.46; 234.67 ± 10.1; and 24.81 ± 0.75 mg/g, respectively) contributing to excellent free radical scavenging potency. In both the LPS-activated inflammation model and the prophylactic model, all tea extracts suppressed NO secretion in a dose-dependent manner, especially for PG. Intriguingly, most tea extracts enhanced expressions of IL-6 in LPS-stimulated macrophages, except PG. However, all teas disrupted downstream transduction of chemoattractant MCP-1 for immune cell trafficking. In the prophylactic model, all teas inhibited inflammatory responses by attenuating expressions of IL-6 and TNF-α in a dose-dependent manner, especially for TG and PG. Our prophylactic model demonstrated PG exerts robust effects on modulating LPS-induced cytokine expressions of MCP-1, IL-6 and TNF-α through scavenging free radicals and NO. In light of the prophylactic effects on LPS-related inflammation, PG effectively scavenges free radicals to modulate cytokine cascades that could serve as a functional beverage for immunomodulation.

4.
Proc Natl Acad Sci U S A ; 116(8): 3300-3309, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30723146

RESUMO

The rice SUB1A-1 gene, which encodes a group VII ethylene response factor (ERFVII), plays a pivotal role in rice survival under flooding stress, as well as other abiotic stresses. In Arabidopsis, five ERFVII factors play roles in regulating hypoxic responses. A characteristic feature of Arabidopsis ERFVIIs is a destabilizing N terminus, which functions as an N-degron that targets them for degradation via the oxygen-dependent N-end rule pathway of proteolysis, but permits their stabilization during hypoxia for hypoxia-responsive signaling. Despite having the canonical N-degron sequence, SUB1A-1 is not under N-end rule regulation, suggesting a distinct hypoxia signaling pathway in rice during submergence. Herein we show that two other rice ERFVIIs gene, ERF66 and ERF67, are directly transcriptionally up-regulated by SUB1A-1 under submergence. In contrast to SUB1A-1, ERF66 and ERF67 are substrates of the N-end rule pathway that are stabilized under hypoxia and may be responsible for triggering a stronger transcriptional response to promote submergence survival. In support of this, overexpression of ERF66 or ERF67 leads to activation of anaerobic survival genes and enhanced submergence tolerance. Furthermore, by using structural and protein-interaction analyses, we show that the C terminus of SUB1A-1 prevents its degradation via the N-end rule and directly interacts with the SUB1A-1 N terminus, which may explain the enhanced stability of SUB1A-1 despite bearing an N-degron sequence. In summary, our results suggest that SUB1A-1, ERF66, and ERF67 form a regulatory cascade involving transcriptional and N-end rule control, which allows rice to distinguish flooding from other SUB1A-1-regulated stresses.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Oryza/genética , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Adaptação Fisiológica/genética , Anaerobiose/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Oryza/crescimento & desenvolvimento , Transdução de Sinais/genética , Especificidade por Substrato
5.
Toxicol Appl Pharmacol ; 424: 115581, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34019859

RESUMO

Oral squamous cell carcinoma (OSCC) is among the most prevalent cancers of the head and neck. This study revealed that isoorientin attenuates OSCC cell stemness and epithelial-mesenchymal transition potential through the inhibition of JAK/signal transducer and activator of transcription 3 (STAT3) and Wnt/ß-catenin signaling in cell lines. Our findings indicated that isoorientin is a potential inhibitor of ß-catenin/STAT3 in vitro and in vivo. We analyzed possible synergism between isoorientin and cisplatin in OSCC. A sulforhodamine B assay, colony formation assay, tumorsphere-formation assay, and Wnt reporter activity assay were used for determining cell invasion, cell migration, drug cytotoxicity, and cell viability with potential molecular mechanisms in vitro. Isoorientin reduced the expression of p-STAT3, ß-catenin, and p-GSK3 as well as downstream effectors TCF1/TCF7 and LEF1 and significantly reduced ß-catenin colocalization in the nucleus. Isoorientin markedly strengthened the cytotoxic effects of cisplatin against SAS and SCC-25. Therefore, combining isoorientin and cisplatin treatments can potentially improve the anticancer effect of cisplatin. Isoorientin inhibited the tumorigenicity and growth of OSCC through the abrogation of Wnt/ß-catenin/STAT3 signaling in vivo. Thus, isoorientin disrupted the ß-catenin signaling pathway through the inactivation of STAT3 signaling. In conclusion, targeting OSCC-SC-mediated stemness with isoorientin to eradicate OSCC-SCs may be an effective strategy for preventing relapse and metastasis of OSCC and providing long-term survival benefits.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Luteolina/farmacologia , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Luteolina/administração & dosagem , Luteolina/química , Camundongos , Estrutura Molecular , Neoplasias Experimentais , Células-Tronco Neoplásicas , Interferência de RNA , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
6.
Toxicol Appl Pharmacol ; 422: 115493, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33727089

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) has a more aggressive phenotype and poorer prognosis than hormone receptor (HR+) and human epidermal growth factor receptor (HER2 -) subtypes. Inhibition of cyclin-dependent kinase (CDK)4 and CDK6 was successful in patients with advanced metastatic HR+/HER2- breast cancer, but those with TNBC exhibited low or no response to this therapeutic approach. This study investigated the dual therapeutic targeting of CDK2 and CDK4 by using 4-acetyl-antroquinonol B (4-AAQB) against TNBC cells. METHODS: We examined the effects of CDK2, CDK4, and CDK6 inhibition through 4-AAQB treatment on TNBC cell lines and established an orthotropic xenograft mouse model to confirm the in vitro results of inhibiting CDK2, CDK4, and CDK6 by 4-AAQB treatment. RESULTS: High expression and alteration of CDK2 and CDK4 but not CDK6 significantly correlated with poor overall survival of patients with breast cancer. CDK2 and CDK4 were positively correlated with damage in DNA replication and repair pathways. Docking results indicated that 4-AAQB was bound to CDK2 and CDK4 with high affinity. Treatment of TNBC cells with 4-AAQB suppressed the expression of CDK2 and CDK4 in vitro. Additionally, 4-AAQB induced cell cycle arrest, DNA damage, and apoptosis in TNBC cells. In vivo study results confirmed that the anticancer activity of 4-AAQB suppressed tumor growth through the inhibition of CDK2 and CDK4. CONCLUSION: The expression level of CDK2 and CDK4 and DNA damage response (DDR) signaling are prominent in TNBC cell cycle regulation. Thus, 4-AAQB is a potential agent for targeting CDK2/4 and DDR in TNBC cells.


Assuntos
4-Butirolactona/análogos & derivados , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Quinase 2 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Cicloexanonas/farmacologia , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , 4-Butirolactona/farmacologia , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase 2 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/genética , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/enzimologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Arch Biochem Biophys ; 705: 108895, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33933426

RESUMO

BACKGROUND: Adipose-derived stem cells (ADSCs), a subpopulation of mesenchymal stem cells, are characterized by their potential to differentiate into multiple cell lineages. Due to their abundance and relative ease of procurement, ADSCs are widely used for tissue repair and regeneration. However, the molecular mechanisms of the therapeutic effect of ADSCs remain unknown. METHODS: MicroRNAs have emerged as important signaling molecules in skin wound healing, and their roles in ADSC-based therapies must be addressed. Here, we investigated the potential of ADSCs in improving cutaneous wound healing in vitro and in vivo. RESULTS: We simulated the microenvironment of the wound site by coculturing human dermal fibroblasts (HDFs) with ADSCs. We found that cocultured HDFs expressed significantly higher levels of miR-29b and miR-21 and had higher proliferation and migration rates than ADSCs cultured without HDFs. Moreover, increased expression of Collagen Type I Alpha 1 Chain (COL1A1), Collagen Type III Alpha 1 Chain (COL3A1), alpha-smooth muscle actin (α-SMA), vascular endothelial growth factor (VEGF), and Phosphoinositide 3-kinase (PI3K), p-Akt and decreased expression of Phosphatase and tensin homolog (PTEN) and matrix metalloproteinase (MMP)-1 was detected, suggesting extracellular remodeling and fibroblast activation and proliferation. We validated the in vitro results by using a rodent skin excisional wound model and implanted ADSC sheets in the wound. Compared with the controls, wounds implanted with ADSC sheets had significantly higher rates of wound-closure; increased expression of α-SMA, VEGF, PI3k, PTEN, COL1A1, and COL3A1; decreased expression of PTEN and MMP1; and upregulated levels of miR-29b and miR-21 in the skin. CONCLUSION: In summary, we evidenced that ADSCs facilitate the increase in miR-29b and miR-21 levels and promote the activation and proliferation of dermal fibroblasts and extracellular matrix (ECM) remodeling, with the associated release of VEGF. Thus, the ADSC-mediated increase in microRNAs is essential in tissue repair and has a therapeutic potential in cutaneous wound healing.


Assuntos
Tecido Adiposo/citologia , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células-Tronco/citologia , Regulação para Cima , Cicatrização , Cadeia alfa 1 do Colágeno Tipo I , Humanos , Transdução de Sinais
8.
Nutr Cancer ; 72(2): 209-217, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31179754

RESUMO

To investigate the influence of longan flower extract (LFE) on the sensitization of colorectal cancer (CRC) cells to 5-fluorouracil (5-FU) treatment, HT-29, Colo 320DM and SW480 cells were treated with LFE and 5-FU alone and in combination, and the cell viability was then assessed by trypan blue exclusion, the cell cycle by propidium iodide staining, the mitochondria membrane potential by rhodamine 123 staining, and the expression levels of associated genes by immunoblotting and quantitative real-time polymerase chain reaction. LFE and 5-FU synergistically inhibited cell proliferation of HT-29 and Colo 320DM cells. Combined treatment also elevated the level of loss of mitochondria membrane potential of these two CRC cells and arrested HT-29 cells in the S phase of the cell cycle, in association with down-regulation of cyclin A mRNA expression. LFE synergistically potentiated chemosensitivity to 5-FU in at least two CRC cell lines. The results indicated that LFE has potential as a novel agent for the sensitization of CRC cells to 5-FU.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Sinergismo Farmacológico , Flores/química , Fluoruracila/farmacologia , Extratos Vegetais/farmacologia , Sapindaceae/química , Apoptose , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Humanos , Extratos Vegetais/química
9.
Int Ophthalmol ; 39(12): 2731-2739, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31359236

RESUMO

BACKGROUND: To investigate the incidence and prevalence of dry eye disease (DED) in Taiwan and to explore its potential risk factors. METHODS: Population-based longitudinal data from 2000 to 2013 based on Taiwan National Health Insurance Research Database were used in this study. To explore potential risks factor of interest, patients who had DED diagnosis before the exposure were excluded. Each patient from the exposure and his/her matched non-exposure controls were followed until either the diagnosis of DED or censorship. Kaplan-Meier method was used to compare the hazard of DED between cohorts. Stratified Cox proportional hazard models were applied to estimate the adjusted effect. RESULTS: The age-adjusted prevalence for men and women were 6.81% and 16.16%, respectively. The age-gender rate of the same period was 549 per 105 person-years. The propensity-adjusted hazard ratio of DED is 1.816 for the presbyopia versus non-presbyopia (with 95% CI = [1.737, 1.897] with p value < 0.0001). CONCLUSIONS: The DED incidence for women peaked at age 50-74, while that for men peaked at age ≧ 75. The incidence in young people seems stable both for women and for men. While exploring the factors of DED, there is a significant association between presbyopia and DED even after matching age/gender and comorbidity conditions. Further clinical studies are needed to justify whether the corrective refractive treatment such as presbyopic glasses to treat the frequently hyperopic status of these patients could be beneficial to both dry eye and presbyopic condition.


Assuntos
Síndromes do Olho Seco/epidemiologia , Presbiopia/complicações , Adulto , Distribuição por Idade , Idoso , Estudos Transversais , Síndromes do Olho Seco/etiologia , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Modelos de Riscos Proporcionais , Fatores de Risco , Taiwan/epidemiologia , Adulto Jovem
10.
Biol Reprod ; 96(3): 707-719, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28339678

RESUMO

Spermatogonial stem cells (SSC) are essential for spermatogenesis and male fertility. In addition, these adult tissue stem cells can be used as vehicles for germline modification in animal models and may have application for treating male infertility. To facilitate the investigation of SSCs and germ lineage development in rats, we generated a DEAD-box helicase 4 (DDX4) (VASA) promoter-enhanced green fluorescent protein (EGFP) reporter transgenic rat. Quantitative real-time polymerase chain reaction and immunofluorescence confirmed that EGFP was expressed in the germ cells of the ovaries and testes and was absent in somatic cells and tissues. Germ cell transplantation demonstrated that the EGFP-positive germ cell population from DDX4-EGFP rat testes contained SSCs capable of establishing spermatogenesis in experimentally infertile mouse recipient testes. EGFP-positive germ cells could be easily isolated by fluorescence-activated cells sorting, while simultaneously removing testicular somatic cells from DDX4-EGFP rat pup testes. The EGFP-positive fraction provided an optimal cell suspension to establish rat SSC cultures that maintained long-term expression of zinc finger and BTB domain containing 16 (ZBTB16) and spalt-like transcription factor 4 (SALL4), two markers of mouse SSCs that are conserved in rats. The novel DDX4-EGFP germ cell reporter rat described here combined with previously described GCS-EGFP rats, rat SSC culture and gene editing tools will improve the utility of the rat model for studying stem cells and germ lineage development.


Assuntos
RNA Helicases DEAD-box/genética , Células Germinativas/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Modelos Animais , Espermatogênese , Células-Tronco Germinativas Adultas , Animais , Células Cultivadas , Feminino , Genes Reporter , Masculino , Regiões Promotoras Genéticas , Ratos Sprague-Dawley , Ratos Transgênicos
11.
BMC Complement Altern Med ; 17(1): 16, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28056952

RESUMO

BACKGROUND: Litchi seeds possess rich amounts of phenolics and have been shown to inhibit proliferation of several types of cancer cells. However, the suppression of EGFR signaling in non-small cell lung cancer (NSCLC) by litchi seed extract (LCSE) has not been fully understood. METHODS: In this study, the effects of LCSE on EGFR signaling, cell proliferation, the cell cycle and apoptosis in A549 adenocarcinoma cells and NCI- H661 large-cell carcinoma cells were examined. RESULTS: The results demonstrated that LCSE potently reduced the number of cancer cells and induced growth inhibition, cell-cycle arrest in the G1 or G2/M phase, and apoptotic death in the cellular experiment. Only low cytotoxicity effect was noted in normal lung MRC-5 cells. LCSE also suppressed cyclins and Bcl-2 and elevated Kip1/p27, Bax and caspase 8, 9 and 3 activities, which are closely associated with the downregulation of EGFR and its downstream Akt and Erk-1/-2 signaling. CONCLUSION: The results implied that LCSE suppressed EGFR signaling and inhibited NSCLC cell growth. This study provided in vitro evidence that LCSE could serve as a potential agent for the adjuvant treatment of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/metabolismo , Litchi/química , Neoplasias Pulmonares/metabolismo , Sementes/química , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/fisiopatologia
12.
Crit Rev Food Sci Nutr ; 56(2): 292-305, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-24762327

RESUMO

This review discusses an analytical technique that combines differential scanning calorimetry and Fourier-transform infrared (DSC-FTIR) microspectroscopy, which simulates the accelerated stability test and detects decomposition products simultaneously in real time. We show that the DSC-FTIR technique is a fast, simple and powerful analytical tool with applications in food sciences. This technique has been applied successfully to the simultaneous investigation of: encapsulated squid oil stability; the dehydration and intramolecular condensation of sweetener (aspartame); the dehydration, rehydration and solidification of trehalose; and online monitoring of the Maillard reaction for glucose (Glc)/asparagine (Asn) in the solid state. This technique delivers rapid and appropriate interpretations with food science applications.


Assuntos
Varredura Diferencial de Calorimetria/métodos , Análise de Alimentos/métodos , Análise de Alimentos/normas , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Varredura Diferencial de Calorimetria/instrumentação , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier/instrumentação
13.
Nano Lett ; 13(6): 2387-92, 2013 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-23621647

RESUMO

Using cross-sectional scanning tunneling microscope (XSTM) with samples cleaved in situ in an ultrahigh vacuum chamber, this study demonstrates the direct visualization of high-resolution interfacial band mapping images across the film thickness in an optimized bulk heterojunction polymer solar cell consisting of nanoscale phase segregated blends of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM). We were able to achieve the direct observation of the interfacial band alignments at the donor (P3HT)-acceptor (PCBM) interfaces and at the interfaces between the photoactive P3HT:PCBM blends and the poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) anode modification layer with an atomic-scale spatial resolution. The unique advantage of using XSTM to characterize polymer/fullerene bulk heterojunction solar cells allows us to explore simultaneously the quantitative link between the vertical morphologies and their corresponding local electronic properties. This provides an atomic insight of interfacial band alignments between the two opposite electrodes, which will be crucial for improving the efficiencies of the charge generation, transport, and collection and the corresponding device performance of polymer solar cells.

14.
Int J Nurs Stud ; 156: 104797, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38788263

RESUMO

BACKGROUND: ICU readmissions and post-discharge mortality pose significant challenges. Previous studies used EHRs and machine learning models, but mostly focused on structured data. Nursing records contain crucial unstructured information, but their utilization is challenging. Natural language processing (NLP) can extract structured features from clinical text. This study proposes the Crucial Nursing Description Extractor (CNDE) to predict post-ICU discharge mortality rates and identify high-risk patients for unplanned readmission by analyzing electronic nursing records. OBJECTIVE: Developed a deep neural network (NurnaNet) with the ability to perceive nursing records, combined with a bio-clinical medicine pre-trained language model (BioClinicalBERT) to analyze the electronic health records (EHRs) in the MIMIC III dataset to predict the death of patients within six month and two year risk. DESIGN: A cohort and system development design was used. SETTING(S): Based on data extracted from MIMIC-III, a database of critically ill in the US between 2001 and 2012, the results were analyzed. PARTICIPANTS: We calculated patients' age using admission time and date of birth information from the MIMIC dataset. Patients under 18 or over 89 years old, or who died in the hospital, were excluded. We analyzed 16,973 nursing records from patients' ICU stays. METHODS: We have developed a technology called the Crucial Nursing Description Extractor (CNDE), which extracts key content from text. We use the logarithmic likelihood ratio to extract keywords and combine BioClinicalBERT. We predict the survival of discharged patients after six months and two years and evaluate the performance of the model using precision, recall, the F1-score, the receiver operating characteristic curve (ROC curve), the area under the curve (AUC), and the precision-recall curve (PR curve). RESULTS: The research findings indicate that NurnaNet achieved good F1-scores (0.67030, 0.70874) within six months and two years. Compared to using BioClinicalBERT alone, there was an improvement in performance of 2.05 % and 1.08 % for predictions within six months and two years, respectively. CONCLUSIONS: CNDE can effectively reduce long-form records and extract key content. NurnaNet has a good F1-score in analyzing the data of nursing records, which helps to identify the risk of death of patients after leaving the hospital and adjust the regular follow-up and treatment plan of relevant medical care as soon as possible.


Assuntos
Redes Neurais de Computação , Alta do Paciente , Humanos , Alta do Paciente/estatística & dados numéricos , Registros de Enfermagem , Registros Eletrônicos de Saúde , Pessoa de Meia-Idade , Feminino , Idoso , Masculino , Medição de Risco/métodos , Processamento de Linguagem Natural , Estudos de Coortes
15.
J Agric Food Chem ; 72(15): 8760-8773, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38536213

RESUMO

Roasting is pivotal for enhancing the flavor of Wuyi rock tea (WRT). A study investigated a novel compound that enhances the umami taste of WRT. Metabolomics of Shuixian tea (SXT) and Rougui tea (RGT) under light roasting (LR), medium roasting (MR), and heavy roasting (HR) revealed significant differences in nonvolatiles compounds. Compared LR reducing sugars and amino acids notably decreased in MR and HR, with l-alanine declining by 69%. Taste-guided fractionation identified fraction II-B as having high umami and sweet intensities. A surprising taste enhancer, N-(1-carboxyethyl)-6-(hydroxymethyl) pyridinium-3-ol (alapyridaine), was discovered and identified. It formed via the Maillard reaction, positively correlated with roasting in SXT and RGT. Alapyridaine levels were highest in SXT among the five oolong teas. Roasting tea with glucose increased alapyridaine levels, while EGCG inhibited its formation. HR-WRT exhibited enhanced umami and sweet taste, highlighting alapyridaine's impact on WRT's flavor profile. The formation of alapyridaine during the roasting process provides new insights into the umami and sweet perception of oolong tea.


Assuntos
Alanina/análogos & derivados , Reação de Maillard , Piridinas , Paladar , Alanina/química , Chá
16.
J Agric Food Chem ; 72(15): 8715-8730, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38564531

RESUMO

Wuyi Rock tea, specifically Shuixian and Rougui, exhibits distinct sensory characteristics. In this study, we investigated the sensory and metabolite differences between Shuixian and Rougui. Quantitative description analysis revealed that Rougui exhibited higher intensity in bitter, thick, harsh, and numb tastes, while Shuixian had stronger salty and umami tastes. Nontargeted metabolomics identified 151 compounds with 66 compounds identified as key differential metabolites responsible for metabolic discrimination. Most of the catechins and flavonoids were enriched in Rougui tea, while epigallocatechin-3,3'-di-O-gallate, epigallocatechin-3,5-di-O-gallate, gallocatechin-3,5-di-O-gallate, isovitexin, and theaflavanoside I were enriched in Shuixian tea. Catechins, kaempferol, quercetin, and myricetin derivatives were positively correlated with bitter taste and numb sensation. Sour taste was positively correlated to organic acids. Amino acids potentially contributed to salty and umami tastes. These results provide further insights into the taste characteristics and the relationship between taste attributes and specific metabolites in Wuyi Rock tea.


Assuntos
Catequina , Paladar , Chá/química , Espectrometria de Massa com Cromatografia Líquida , Cromatografia Líquida , Espectrometria de Massas em Tandem , Metabolômica/métodos
17.
Curr Res Food Sci ; 6: 100442, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36687170

RESUMO

Roasting plays important roles in shaping the volatile profile of oolong tea. In this study, the sensory attributes and volatile compositions of 153 roasted or unroasted oolong tea samples, belonging to four typical types, namely, High Mountain oolong tea (HMT), Tieguanyin tea (TGYT), Dongding oolong tea (DDT) and Wuyi rock tea (WRT), were studied in detail. Based on the sensory evaluation by tea evaluation experts, their respective sensory profiles were established and compared. Unroasted teas had more pronounced fresh and green flavors, while roasted teas had higher scores in pungent and caramel flavors. In particular, WRT demonstrated a unique fragrance of floral fruity flavors. By using HS-SPME-GC-MS analysis, a total of 128 compounds were identified across all samples. Notably, it was found that roasting largely increased the variety of volatile compounds in oolong tea. Furthermore, the characteristic volatile compounds of each type of tea were identified by PLS-DA modeling. Linalool and geraniol were the characteristic volatiles of HMT. Four volatiles, including (E)-nerolidol, jasmin lactone, benzeneacetaldehyde, and 4-methyl benzaldehyde oxime were identified as the characteristic volatiles of TGYT. Seven volatiles, including N-ethyl pyrrole, 3-(hydroxy methyl) pyridine, 4-pyridylcarbinol, 1-methyl pyrrole-2-carboxaldehyde, 2-ethyl-3,5-dimethyl pyrazine, 4-amino-2,3-xylenol, and 4,6-dimethyl pyrimidine were the characteristic volatiles of DDT. For WRT, 2,2,6-trimethyl cyclohexan-1-one, hexanoic acid, benzaldehyde, benzyl alcohol, ß-cyclocitral, (E)-ß-ionone, α-ionone, and octanoic acid were the characteristic volatiles. These findings expand our knowledge of the volatile fingerprints of oolong tea.

18.
PNAS Nexus ; 2(7): pgad229, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37492276

RESUMO

Most rice (Oryza sativa) cultivars cannot survive under prolonged submergence. However, some O. sativa ssp. indica cultivars, such as FR13A, are highly tolerant owing to the SUBMERGENCE 1A-1 (SUB1A-1) allele, which encodes a Group VII ethylene-responsive factor (ERFVII) protein; other submergence-intolerant cultivars contain a SUB1A-2 allele. The two alleles differ only by a single substitution at the 186th amino acid position from serine in SUB1A-1 to proline in SUB1A-2 resulting in only SUB1A-1 being able to be phosphorylated. Two other ERFVIIs, ERF66 and ERF67, function downstream of SUB1A-1 to form a regulatory cascade in response to submergence stress. Here, we show that SUB1A-1, but not SUB1A-2, interacts with ADA2b of the ADA2b-GCN5 acetyltransferase complex, in which GCN5 functions as a histone acetyltransferase. Phosphorylation of SUB1A-1 at serine 186 enhances the interaction of SUB1A-1 with ADA2b. ADA2b and GCN5 expression was induced under submergence, suggesting that these two genes might play roles in response to submergence stress. In transient assays, binding of SUB1A-1 to the ERF67 promoter and ERF67 transcription were highly induced when SUB1A-1 was expressed together with the ADA2b-GCN5 acetyltransferase complex. Taken together, these results suggest that phospho-SUB1A-1 recruits the ADA2-GCN5 acetyltransferase complex to modify the chromatin structure of the ERF66/ERF67 promoter regions and activate gene expression, which in turn enhances rice submergence tolerance.

19.
Foods ; 12(17)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37685091

RESUMO

The Dong Ding oolong tea (DDT), grown and produced in Taiwan, is widely appreciated for its unique flavor. Despite its popularity, research on the aroma components of DDT remains incomplete. To address this gap, this study employed a sensomics approach to comprehensively characterize the key aroma compounds in DDT. Firstly, sensory evaluation showed that DDT had a prominent caramel aroma. Subsequent analysis using gas chromatography-olfactory mass spectrometry (GC-O-MS) and comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF-MS) identified a total of 23 aroma-active compounds in DDT. Notably, three pyrazine compounds with roasted notes, namely 2-ethyl-5-methylpyrazine, 2-ethyl-3,5-dimethylpyrazine, and 2,3-diethyl-5-methylpyrazine, along with seven floral- and fruit-smelling compounds, namely 6-methyl-5-hepten-2-one, 3,5-octadien-2-one, linalool, (E)-linalool oxide, geraniol, (Z)-jasmone, and (E)-nerolidol, were identified as the key aroma compounds of DDT. Omission experiments further validated the significant contribution of the three pyrazines to the caramel aroma of DDT. Moreover, the content of 2-ethyl-3,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine, (Z)-jasmone, 6-methyl-5-hepten-2-one and 2-ethyl-5-methylpyrazine was found to be higher in the high-grade samples, while (E)-nerolidol, linalool, geraniol and 3,5-octadien-2-one were found to be more abundant in the medium-grade samples. These findings provide valuable information for a better understanding of the flavor attributes of DDT.

20.
Mar Pollut Bull ; 195: 115344, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37793285

RESUMO

This study investigated the conditions of abandoned, lost, discarded fishing gear (ALDFG) in natural and artificial reef zones and removed it afterward in Penghu Islands. Various feasible suggestions for improving ALDFG management were proposed for the county government to manage and reduce the generation of ALDFG in the future and maintain the marine ecosystem. This study divided the ocean areas of Penghu into five sub-areas for carrying out research and surveys. 165 boat trips of ALDFG investigation and removal were conducted from July 2018 to October 2019. The results show the ALDFG in natural reef areas is mostly large-mesh gillnets (26 %). The rest are single-layer bottom gillnets (21 %) and multi-layer bottom gillnets (20 %). In line with the recent efforts of the Penghu County Government to address ALDFG, it is recommended that the participation of citizen scientists and the promotion of ocean education can be utilized for fishery co-management in Penghu.


Assuntos
Ecossistema , Caça , Taiwan , Pesqueiros
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