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1.
BMC Cancer ; 24(1): 410, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566115

RESUMO

BACKGROUND: High expression of the glycosyltransferase UGT2B17 represents an independent adverse prognostic marker in chronic lymphocytic leukemia (CLL). It also constitutes a predictive marker for therapeutic response and a drug resistance mechanism. The key determinants driving expression of the UGT2B17 gene in normal and leukemic B-cells remain undefined. The UGT2B17 transcriptome is complex and is comprised of at least 10 alternative transcripts, identified by previous RNA-sequencing of liver and intestine. We hypothesized that the transcriptional program regulating UGT2B17 in B-lymphocytes is distinct from the canonical expression previously characterized in the liver. RESULTS: RNA-sequencing and genomics data revealed a specific genomic landscape at the UGT2B17 locus in normal and leukemic B-cells. RNA-sequencing and quantitative PCR data indicated that the UGT2B17 enzyme is solely encoded by alternative transcripts expressed in CLL patient cells and not by the canonical transcript widely expressed in the liver and intestine. Chromatin accessible regions (ATAC-Seq) in CLL cells mapped with alternative promoters and non-coding exons, which may be derived from endogenous retrotransposon elements. By luciferase reporter assays, we identified key cis-regulatory STAT3, RELA and interferon regulatory factor (IRF) binding sequences driving the expression of UGT2B17 in lymphoblastoid and leukemic B-cells. Electrophoretic mobility shift assays and pharmacological inhibition demonstrated key roles for the CLL prosurvival transcription factors STAT3 and NF-κB in the leukemic expression of UGT2B17. CONCLUSIONS: UGT2B17 expression in B-CLL is driven by key regulators of CLL progression. Our data suggest that a NF-κB/STAT3/IRF/UGT2B17 axis may represent a novel B-cell pathway promoting disease progression and drug resistance.


Assuntos
Leucemia Linfocítica Crônica de Células B , NF-kappa B , Humanos , NF-kappa B/metabolismo , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Prognóstico , Apoptose , RNA , Glucuronosiltransferase/genética , Antígenos de Histocompatibilidade Menor
2.
Mol Cell ; 61(4): 520-534, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26853146

RESUMO

Altered energy metabolism is a cancer hallmark as malignant cells tailor their metabolic pathways to meet their energy requirements. Glucose and glutamine are the major nutrients that fuel cellular metabolism, and the pathways utilizing these nutrients are often altered in cancer. Here, we show that the long ncRNA CCAT2, located at the 8q24 amplicon on cancer risk-associated rs6983267 SNP, regulates cancer metabolism in vitro and in vivo in an allele-specific manner by binding the Cleavage Factor I (CFIm) complex with distinct affinities for the two subunits (CFIm25 and CFIm68). The CCAT2 interaction with the CFIm complex fine-tunes the alternative splicing of Glutaminase (GLS) by selecting the poly(A) site in intron 14 of the precursor mRNA. These findings uncover a complex, allele-specific regulatory mechanism of cancer metabolism orchestrated by the two alleles of a long ncRNA.


Assuntos
Glutaminase/genética , Neoplasias/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo , Alelos , Processamento Alternativo , Metabolismo Energético , Células HCT116 , Humanos , Neoplasias/genética , Precursores de RNA/química , Precursores de RNA/metabolismo , RNA Mensageiro/metabolismo
3.
Medicina (Kaunas) ; 60(6)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38929629

RESUMO

Background and Objectives: Malaria continues to be a significant global health challenge. The efficacy of artemisinin-based combination therapies (ACTs) has declined in many parts of the Greater Mekong Subregion, including Vietnam, due to the spread of resistant malaria strains. This study was conducted to assess the efficacy of the Dihydroartemisinin (DHA)-Piperaquine (PPQ) regimen in treating uncomplicated falciparum malaria and to conduct molecular surveillance of antimalarial drug resistance in Binh Phuoc and Dak Nong provinces. Materials and Methods: The study included 63 uncomplicated malaria falciparum patients from therapeutic efficacy studies (TES) treated following the WHO treatment guidelines (2009). Molecular marker analysis was performed on all 63 patients. Methods encompassed Sanger sequencing for pfK13 mutations and quantitative real-time PCR for the pfpm2 gene. Results: This study found a marked decrease in the efficacy of the DHA-PPQ regimen, with an increased rate of treatment failures at two study sites. Genetic analysis revealed a significant presence of pfK13 mutations and pfpm2 amplifications, indicating emerging resistance to artemisinin and its partner drug. Conclusions: The effectiveness of the standard DHA-PPQ regimen has sharply declined, with rising treatment failure rates. This decline necessitates a review and possible revision of national malaria treatment guidelines. Importantly, molecular monitoring and clinical efficacy assessments together provide a robust framework for understanding and addressing detection drug resistance in malaria.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Plasmodium falciparum , Quinolinas , Humanos , Artemisininas/uso terapêutico , Quinolinas/uso terapêutico , Vietnã , Antimaláricos/uso terapêutico , Malária Falciparum/tratamento farmacológico , Masculino , Feminino , Adulto , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Resistência a Medicamentos/genética , Adolescente , Pessoa de Meia-Idade , Quimioterapia Combinada/métodos , Adulto Jovem , Proteínas de Protozoários/genética , Reação em Cadeia da Polimerase em Tempo Real , Mutação , Piperazinas
4.
Br J Cancer ; 128(2): 285-296, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36347965

RESUMO

BACKGROUND: Naturally occurring germline gene deletions (KO) represent a unique setting to interrogate gene functions. Complete deletions and differential expression of the human glycosyltransferase UGT2B17 and UGT2B28 genes are linked to prostate cancer (PCa) risk and progression, leukaemia, autoimmune and other diseases. METHODS: The systemic metabolic consequences of UGT deficiencies were examined using untargeted and targeted mass spectrometry-based metabolomics profiling of carefully matched, treatment-naive PCa cases. RESULTS: Each UGT KO differentially affected over 5% of the 1545 measured metabolites, with divergent metabolic perturbations influencing the same pathways. Several of the perturbed metabolites are known to promote PCa growth, invasion and metastasis, including steroids, ceramides and kynurenine. In UGT2B17 KO, reduced levels of inactive steroid-glucuronides were compensated by sulfated derivatives that constitute circulating steroid reservoirs. UGT2B28 KO presented remarkably lower levels of oxylipins paralleled by reduced inflammatory mediators, but higher ceramides unveiled as substrates of the enzyme in PCa cells. CONCLUSION: The distinctive and broad metabolic rewiring caused by UGT KO reinforces the need to examine their unique and divergent functions in PCa biology.


Assuntos
Glucuronosiltransferase , Neoplasias da Próstata , Humanos , Masculino , Técnicas de Inativação de Genes , Glucuronídeos , Fenótipo , Neoplasias da Próstata/patologia , Esteroides , Glucuronosiltransferase/genética
5.
Anal Biochem ; 675: 115229, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37393974

RESUMO

Glucagon is a peptide involved in controlling the body's blood glucose levels. The majority of analytical methods used for its quantitation are based on immunoassays that suffer from cross-reactivity with other peptides. For accurate routine analysis a liquid chromatography tandem mass spectrometry (LC-MSMS) was developed. Glucagon was extracted from plasma samples by a combination of protein precipitation using ethanol and mixed anion exchange solid phase extraction. Linearity for glucagon was above 0.99 (r2) up to a concentration range of 771 ng/L with a lower limit of quantification established at 19 ng/L. Precision of the method was below 9% (coefficient of variation). Recovery was 93%. Correlations with the existing immunoassay displayed a significant negative bias.


Assuntos
Glucagon , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Imunoensaio , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos
6.
Nanotechnology ; 34(31)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37130513

RESUMO

This paper presents the successful synthesis of AgInS2nanocrystals (NCs) double-shelled with GaSxand ZnS for emitting bright and narrow excitonic luminescence from AgInS2core NCs. Additionally, the AgInS2/GaSx/ZnS NCs with a core/double-shell structure have demonstrated high chemical and photochemical stability. The AgInS2/GaSx/ZnS NCs were prepared via three steps: (i) synthesis of AgInS2core NCs by solvothermal method at 200 °C for 30 min, (ii) shelling GaSxon AgInS2core NCs at 280 °C for 60 min to produce the AgInS2/GaSxcore/shell structure, and (iii) the outermost ZnS shelling at 140 °C for 10 min. The synthesized NCs were characterized in detail by using appropriate techniques such as x-ray diffraction, transmission electron microscopy, and optical spectroscopies. The luminescence evolution of the synthesized NCs is as follows: from the broad spectrum (peaking at 756 nm) of the AgInS2core NCs to become the narrow excitonic emission (at 575 nm) prominent beside the broad one after shelling with GaSx, then only the bright excitonic luminescence (at 575 nm) without broad emission after double-shelling with GaSx/ZnS. The double-shell has made the AgInS2/GaSx/ZnS NCs not only remarkably enhance their luminescence quantum yield (QY) up to ∼60% but also maintain the narrow excitonic emission stably for a long-term storage over 12 months. The outermost ZnS shell is believed to play a key role in enhancing QY and protecting AgInS2and AgInS2/GaSxfrom certain damage.

7.
Food Microbiol ; 115: 104324, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37567633

RESUMO

In dairy industry, filamentous fungi are used as adjunct cultures in fermented products for their technological properties but they could also be responsible for food spoilage and mycotoxin production. The consumer demands about free-preservative products has increased in recent years and lead to develop alternative methods for food preservation. Modified Atmosphere Packaging (MAP) can inhibit fungal growth and therefore increase the food product shelf-life. This study aimed to evaluate radial growth as a function of CO2 and more particularly carbonic acid for fourteen adjuncts and/or fungal spoiler isolated from dairy products or dairy environment by using predictive mycology tools. The impact of the different chemical species linked to CO2 (notably carbonic acid) were study because it was reported previously that undissociated carbonic acid impacted bacterial growth and bicarbonates ions were involved in modifications of physiological process of fungal cells. A significant diversity in the responses of selected strains was observed. Mucor circinelloides had the fastest growth rates (µ > 11 mm. day-1) while Bisifusarium domesticum, Cladosporium herbarum and Penicillium bialowiezense had the slowest growth rates (µ < 1 mm. day-1). Independently of the medium pH, the majority of strains were sensitive to total carbonic acid. In this case, it was not possible to conclude if CO2 active form was gaseous or aqueous so modeling were performed as a function of CO2 percentage. Only Geotrichum candidum and M. circinelloides strains were sensitive to undissociated carbonic acid. Among the fourteen strains, P. bialowiezense was the less sensitive strain to CO2, no growth was observed at 50% of CO2 only for this strain. M. lanceolatus was the less sensitive strain to CO2, the CO250 which reduce the growth rates by 50% was estimated at 138% of CO2. Low CO2 percentage improved the growth of Penicillium expansum, Penicillium roqueforti and Paecilomyces niveus. Mathematical models (without and with optimum) were suggested to describe the impact of CO2 percentage or undissociated carbonic acid concentration on fungal growth rate.


Assuntos
Dióxido de Carbono , Ácido Carbônico , Dióxido de Carbono/farmacologia , Fungos , Laticínios/microbiologia , Conservação de Alimentos/métodos
8.
Food Microbiol ; 115: 104309, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37567615

RESUMO

Penicillium camemberti is a domesticated species adapted to the dairy environment, which is used as adjunct cultures to ripen soft cheeses. A recent population genomics analysis on P. camemberti revealed that P. camemberti is a clonal lineage with two varieties almost identical genetically but with contrasting phenotypes in terms of growth, color, mycotoxin production and inhibition of contaminants. P. camemberti variety camemberti is found on Camembert and Brie cheeses, and P. camemberti variety caseifulvum is mainly found on other cheeses like Saint-Marcellin and Rigotte de Condrieu. This study aimed to evaluate the impact of water activity (aw) reduced by sodium chloride (NaCl) and the increase of carbon dioxide (CO2) partial pressure, on conidial germination and growth of two varieties of P. camemberti: var. Camemberti and var. Caseifulvum. Mathematical models were used to describe the responses of P. camemberti strains to both abiotic factors. The results showed that these genetically distant strains had similar responses to increase in NaCl and CO2 partial pressure. The estimated cardinal values were very close between the strains although all estimated cardinal values were significantly different (Likelihood ratio tests, pvalue = 0.05%). These results suggest that intraspecific variability could be more exacerbated during fungal growth compared with conidial germination, especially in terms of macroscopic morphology. Indeed, var. Caseifulvum seemed to be more sensitive to an increase of CO2 partial pressure, as shown by the fungal morphology, with the occurrence of irregular outgrowths, while the morphology of var. Camemberti remains circular. These data could make it possible to improve the control of fungal development as a function of salt and carbon dioxide partial pressure. These abiotic factors could serve as technological barriers to prevent spoilage and increase the shelf life of cheeses. The present data will allow more precise predictions of fungal proliferation as a function of salt and carbon dioxide partial pressure, which are significant technological hurdles in cheese production.


Assuntos
Queijo , Penicillium , Cloreto de Sódio/farmacologia , Esporos Fúngicos , Dióxido de Carbono , Queijo/microbiologia
9.
J Digit Imaging ; 36(3): 911-922, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36717518

RESUMO

The malignant tumors in nature share some common morphological characteristics. Radiomics is not only images but also data; we think that a probability exists in a set of radiomics signatures extracted from CT scan images of one cancer tumor in one specific organ also be utilized for overall survival prediction in different types of cancers in different organs. The retrospective study enrolled four data sets of cancer patients in three different organs (420, 157, 137, and 191 patients for lung 1 training, lung 2 testing, and two external validation set: kidney and head and neck, respectively). In the training set, radiomics features were obtained from CT scan images, and essential features were chosen by LASSO algorithm. Univariable and multivariable analyses were then conducted to find a radiomics signature via Cox proportional hazard regression. The Kaplan-Meier curve was performed based on the risk score. The integrated time-dependent area under the ROC curve (iAUC) was calculated for each predictive model. In the training set, Kaplan-Meier curve classified patients as high or low-risk groups (p-value < 0.001; log-rank test). The risk score of radiomics signature was locked and independently evaluated in the testing set, and two external validation sets showed significant differences (p-value < 0.05; log-rank test). A combined model (radiomics + clinical) showed improved iAUC in lung 1, lung 2, head and neck, and kidney data set are 0.621 (95% CI 0.588, 0.654), 0.736 (95% CI 0.654, 0.819), 0.732 (95% CI 0.655, 0.809), and 0.834 (95% CI 0.722, 0.946), respectively. We believe that CT-based radiomics signatures for predicting overall survival in various cancer sites may exist.


Assuntos
Neoplasias , Humanos , Estudos Retrospectivos , Neoplasias/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Pescoço , Rim
10.
Int J Mol Sci ; 24(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37834406

RESUMO

Antioxidant and anti-inflammatory mechanisms counteract the pathogenesis of chronic diseases, such as diabetes, aging, and cancer. Therefore, enhancing antioxidant and anti-inflammatory functions may help manage these pathological conditions. This study aimed to assess the antioxidant and anti-inflammatory potentials of lipophilic fraction of Liriope platyphylla seeds (LLPS) using network pharmacology, molecular docking, and in vitro experiments. Here GC-MS analysis tentatively identified forty-three lipophilic compounds in LLPS. LLPS exhibited powerful antioxidant activity, according to the results from chemical-based antioxidant assays on DPPH, ABTS+, superoxide anion, hydrogen peroxide, nitric oxide, and hydroxyl radicals scavenging, lipid peroxidation, reducing antioxidant powers, and total antioxidant capacity. Additionally, LLPS enhanced cellular antioxidant capacity by inhibiting reactive oxygen species formation and elevating antioxidant enzyme levels, including catalase and heme oxygenase-1. Moreover, LLPS attenuated inflammatory response by reducing nitric oxide secretion and downregulating the expression of inducible nitric oxide synthase, cyclooxygenase-2, and interleukin-1ß in lipopolysaccharide-treated macrophages. Network pharmacology and molecular docking analyses showed that key compounds in LPPS, particularly phytosterols and fatty acid esters, exerted antioxidant and anti-inflammatory properties through regulating NFKB1, PTGS1, PTGS2, TLR4, PRKCA, PRKCD, KEAP1, NFE2L2, and NR1l2. Overall, these data suggest that LLPS may be a potential antioxidant and anti-inflammatory agent for developing functional foods.


Assuntos
Antioxidantes , Óxido Nítrico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Simulação de Acoplamento Molecular , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Óxido Nítrico/metabolismo , Farmacologia em Rede , Fator 2 Relacionado a NF-E2/metabolismo , Anti-Inflamatórios/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
11.
BMC Cancer ; 22(1): 526, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35545761

RESUMO

BACKGROUND: A current critical need remains in the identification of prognostic and predictive markers in early breast cancer. It appears that a distinctive trait of cancer cells is their addiction to hyperactivation of ribosome biogenesis. Thus, ribosome biogenesis might be an innovative source of biomarkers that remains to be evaluated. METHODS: Here, fibrillarin (FBL) was used as a surrogate marker of ribosome biogenesis due to its essential role in the early steps of ribosome biogenesis and its association with poor prognosis in breast cancer when overexpressed. Using 3,275 non-metastatic primary breast tumors, we analysed FBL mRNA expression levels and protein nucleolar organisation. Usage of TCGA dataset allowed transcriptomic comparison between the different FBL expression levels-related breast tumours. RESULTS: We unexpectedly discovered that in addition to breast tumours expressing high level of FBL, about 10% of the breast tumors express low level of FBL. A correlation between low FBL mRNA level and lack of FBL detection at protein level using immunohistochemistry was observed. Interestingly, multivariate analyses revealed that these low FBL tumors displayed poor outcome compared to current clinical gold standards. Transcriptomic data revealed that FBL expression is proportionally associated with distinct amount of ribosomes, low FBL level being associated with low amount of ribosomes. Moreover, the molecular programs supported by low and high FBL expressing tumors were distinct. CONCLUSION: Altogether, we identified FBL as a powerful ribosome biogenesis-related independent marker of breast cancer outcome. Surprisingly we unveil a dual association of the ribosome biogenesis FBL factor with prognosis. These data suggest that hyper- but also hypo-activation of ribosome biogenesis are molecular traits of distinct tumors.


Assuntos
Neoplasias da Mama , Biomarcadores/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proteínas Cromossômicas não Histona , Feminino , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribossomos/genética , Ribossomos/metabolismo
12.
Appl Opt ; 61(33): 10064, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36606841

RESUMO

This publisher's note corrects errors in Appl. Opt.61, 9078 (2022)APOPAI0003-693510.1364/AO.471949.

13.
Appl Opt ; 61(30): 9078-9084, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36607040

RESUMO

A reconfigurable metamaterial absorber (MA) in the microwave region is numerically and experimentally demonstrated based on a multi-layered metamaterial. The proposed structure can be mechanically switched between two different configurations to obtain designated absorption behaviors. By rotating the upper ring layer by multiples of 90 deg, two separated absorption modes of the MA are created. The first configuration acts as a single-band absorber, while the second configuration performs multi-band perfect absorption. In addition, the proposed structure can be easily switched into two different configurations to obtain a designated absorption feature. Our work is expected to provide an effective approach to obtaining reconfigurable MAs, which are useful for various applications.

14.
Molecules ; 27(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36234931

RESUMO

Sweet pepper fruits (Capsicum annuum L.) contain various nutrients and phytochemicals that enhance human health and prevent the pathogenesis of certain diseases. Here, we report that oral administration of orange sweet pepper juices prepared by a high-speed blender and low-speed masticating juicer reduces UVB-induced skin damage in SKH-1 hairless mice. Sweet pepper juices reduced UVB-induced skin photoaging by the regulation of genes involved in dermal matrix production and maintenance such as collagen type I α 1 and matrix metalloproteinase-2, 3, 9. Administration of sweet pepper juices also restored total collagen levels in UVB-exposed mice. In addition, sweet pepper juices downregulated the expression of pro-inflammatory proteins such as cyclooxygenase-2, interleukin (IL)-1ß, IL-17, and IL-23, which was likely via inhibiting the NF-κB pathway. Moreover, primary antioxidant enzymes in the skin were enhanced by oral supplementation of sweet pepper juices, as evidenced by increased expression of catalase, glutathione peroxidase, and superoxide dismutase-2. Immunohistochemical staining showed that sweet pepper juices reduced UVB-induced DNA damage by preventing 8-OHdG formation. These results suggest that sweet pepper juices may offer a protective effect against photoaging by inhibiting the breakdown of dermal matrix, inflammatory response, and DNA damage as well as enhancing antioxidant defense, which leads to an overall reduction in skin damage.


Assuntos
Capsicum , Envelhecimento da Pele , Animais , Antioxidantes/farmacologia , Capsicum/metabolismo , Catalase , Colágeno Tipo I , Ciclo-Oxigenase 2 , Glutationa Peroxidase , Humanos , Interleucina-17 , Interleucina-23 , Metaloproteinase 2 da Matriz , Camundongos , Camundongos Pelados , NF-kappa B/metabolismo , Compostos Fitoquímicos , Pele/metabolismo , Raios Ultravioleta/efeitos adversos
15.
Clin Chem Lab Med ; 59(12): 1944-1949, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34473921

RESUMO

OBJECTIVES: In the clinical setting, the analysis and quantification of vitamin C (ascorbic acid) poses several challenges including analyte instability and poor retention by reverse phase HPLC systems. In this article we describe a rapid hydrophilic interaction chromatography ultraviolet method for the measurement of total vitamin C in plasma which overcomes these issues. METHODS: Ascorbic acid and the internal standard were separated under isocratic conditions using a Waters BEH-Amide column and a mobile phase containing 0.005 M potassium phosphate in 80% acetonitrile. RESULTS: The proposed method was validated and showed good precision (coefficient of variation <5%), accuracy (>99%), and analyte stability after extraction (>24 h). CONCLUSIONS: The simple sample preparation allows full automation and rapid analytical run times of the assay and is therefore suitable for a high-throughput clinical chromatography laboratory.


Assuntos
Ácido Ascórbico , Laboratórios , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Reprodutibilidade dos Testes , Vitaminas
16.
Int J Mol Sci ; 22(17)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34502017

RESUMO

Tea is particularly rich in polyphenols, including catechins and theaflavins, thearubigins, flavonols, and phenolic acids, which are believed to contribute to the health benefits of tea. The health-promoting effects of tea polyphenols are believed to be related to their cellular defensive properties. This review is intended to briefly summarize the relationship between the chemical structures of tea polyphenols and their biological activities. Tea polyphenols appear as direct antioxidants by scavenging reactive oxygen/nitrogen species; chelating transition metals; and inhibiting lipid, protein, and DNA oxidations. They also act directly by suppressing "pro-oxidant" enzymes, inducing endogenous antioxidants, and cooperating with vitamins. Moreover, tea polyphenols regulate cellular signaling transduction pathways, importantly contributing to the prevention of chronic diseases and the promotion of physiological functions. Apparently, the features in the chemical structures of tea polyphenols are closely associated with their antioxidant potentials.


Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacologia , Chá/química , Animais , Flavonoides/metabolismo , Humanos , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade
17.
Anal Biochem ; 594: 113616, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32035844

RESUMO

Flavin adenine dinucleotide (FAD) is an active coenzyme of vitamin B2 involved in oxidation and reduction reactions. In this study we have developed a fully automated method for the analysis of FAD by fluorescence detection. FAD is extracted from whole blood samples by trichloroacetic acid, with diethyl ribityl isoalloxazine used as an internal standard. Linearity for FAD was above 0.99 (r2) up to a concentration range of 1000 nmol/L. Precision of the method (intra-day and inter-day) compared against commercial quality control material was below 8% (coefficient of variation) with recovery of FAD exceeding 90%. Accuracy of the protocol was compared against a previous cycle from an external quality assurance program (RCPAQAP) (n = 12) with satisfactory agreement. Overall, this method has increased laboratory workflow and reduced manual labour required in performing FAD analysis.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavina-Adenina Dinucleotídeo/sangue , Fluorescência , Humanos , Fluxo de Trabalho
18.
Malar J ; 19(1): 458, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33384023

RESUMO

BACKGROUND: While the World Health Organization (WHO) Southeast Asia region has the second highest incidence of malaria worldwide, malaria in Vietnam is focal to few provinces, where delayed parasite clearance to anti-malarial drugs is documented. This study aims to understand Plasmodium species distribution and the genetic diversity of msp1 and msp2 of parasite populations using molecular tools. METHODS: A total of 222 clinical isolates from individuals with uncomplicated malaria were subjected to Plasmodium species identification by nested real-time PCR. 166 isolates positive for Plasmodium falciparum mono infections were further genotyped for msp1 (MAD20, K1, and RO33), and msp2 allelic families (3D7 and FC27). Amplicons were resolved through capillary electrophoresis in the QIAxcel Advanced system. RESULTS: Mono-infections were high and with 75% P. falciparum, 14% Plasmodium vivax and 9% P. falciparum/P. vivax co-infections, with less than 1% Plasmodium malariae identified. For msp1, MAD20 was the most prevalent (99%), followed by K1 (46%) allelic family, with no sample testing positive for RO33 (0%). For msp2, 3D7 allelic family was predominant (97%), followed by FC27 (10%). The multiplicity of infection of msp1 and msp2 was 2.6 and 1.1, respectively, and the mean overall multiplicity of infection was 3.7, with the total number of alleles ranging from 1 to 7. CONCLUSIONS: Given the increasing importance of antimalarial drugs in the region, the genetic diversity of P. falciparum msp1 and msp2 should be regularly monitored with respect to treatment outcomes and/or efficacy studies in regions, where there are ongoing changes in the malaria epidemiology.


Assuntos
Antígenos de Protozoários/genética , Variação Genética , Malária/parasitologia , Proteína 1 de Superfície de Merozoito/genética , Plasmodium falciparum/genética , Plasmodium malariae/genética , Plasmodium vivax/genética , Proteínas de Protozoários/genética , Coinfecção/parasitologia , Genótipo , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Vietnã
19.
Appl Opt ; 59(9): 2924-2928, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32225842

RESUMO

We report values of parametric-model (PM) parameters that can be used to obtain dielectric functions (refractive indices) from 1.5 to 6.0 eV for ${{\rm In}_x}{{\rm Al}_{1 - x}}{\rm P}$InxAl1-xP alloys of arbitrary compositions $x$x. Using reported pseudo-dielectric data for several In compositions, we extract their dielectric functions by multilayer calculations, then parameterize them with PM lineshapes that well describe the asymmetric nature of their critical point (CP) contributions. We follow the ${E_0}$E0 fundamental bandgap as a function of $x$x, and determine the composition of the indirect-to-direct crossover.

20.
Clin Chem Lab Med ; 57(5): 617-622, 2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-30307893

RESUMO

Phosphatidylethanol (PEth) are phospholipids produced through non-oxidative ethanol metabolism. They accumulate in red blood cells and have been traditionally analysed in whole blood as potential biomarkers for moderate to long-term alcohol consumption. More recently, their analysis in dried blood spots has been gaining favour, namely, due to the ease in sampling, transport and storage conditions required. This paper aims at providing a short comparative review between analysing PEth in whole blood and dried blood spots and the potential pitfalls that researchers may face when setting up PEth testing for clinical use.


Assuntos
Glicerofosfolipídeos/sangue , Consumo de Bebidas Alcoólicas/sangue , Alcoolismo/sangue , Biomarcadores/sangue , Teste em Amostras de Sangue Seco/métodos , Hematócrito , Humanos
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