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1.
J Cell Mol Med ; 28(13): e18526, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38957036

RESUMO

A genome-wide association study (GWAS) is a powerful tool in investigating genetic contribution, which is a crucial factor in the development of complex multifactorial diseases, such as type 2 diabetes mellitus. Type 2 diabetes mellitus is a major healthcare burden in the Western Pacific region; however, there is limited availability of genetic-associated data for type 2 diabetes in Southeast Asia, especially among the Kinh Vietnamese population. This lack of information exacerbates global healthcare disparities. In this study, 997 Kinh Vietnamese individuals (503 with type 2 diabetes and 494 controls) were prospectively recruited and their clinical and paraclinical information was recorded. DNA samples were collected and whole genome genotyping was performed. Standard quality control and genetic imputation using the 1000 Genomes database were executed. A polygenic risk score for type 2 diabetes was generated in different models using East Asian, European, and mix ancestry GWAS summary statistics as training datasets. After quality control and genetic imputation, 107 polymorphisms reached suggestive statistical significance for GWAS (≤5 × 10-6) and rs11079784 was one of the potential markers strongly associated with type 2 diabetes in the studied population. The best polygenic risk score model predicting type 2 diabetes mellitus had AUC = 0.70 (95% confidence interval = 0.62-0.77) based on a mix of ancestral GWAS summary statistics. These data show promising results for genetic association with a polygenic risk score estimation in the Kinh Vietnamese population; the results also highlight the essential role of population diversity in a GWAS of type 2 diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2 , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Herança Multifatorial , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/genética , Estratificação de Risco Genético , Herança Multifatorial/genética , Projetos Piloto , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , População do Sudeste Asiático/genética , Vietnã/epidemiologia
2.
Zoolog Sci ; 41(3): 275-280, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38809866

RESUMO

Aposematic coloration plays a crucial role in animal defense, and it is shaped by a complex interplay of factors such as physiological limitations and sexual and natural selection. Warty newts within the genus Paramesotriton exhibit significant variation in ventral coloration. In this study, we quantified the percentage of red ventral area to investigate aposematic ventral coloration in Paramesotriton deloustali and P. guangxiensis across eight populations in northern Vietnam. To assess the interaction between predators and the aposematic signals, we conducted experiments employing three types of clay replicas of newts: dorsal, red ventral, and black ventral models. Our findings revealed a significant variation in the red ventral area among different populations. Additionally, a significant correlation was detected between the red ventral area of the newt and the annual temperature range. In clay model experiments, a significant difference in predator attack rates was observed between dorsal and ventral clay models. Interestingly, there was no significant difference in attack rates between red and black ventral types. Our study suggested that the variation in the red ventral area of warty newts is probably influenced by multiple factors, including genetic constraints, sex, ambient environment, and diet. Furthermore, our results supported the effectiveness of displaying aposematic coloration as an antipredator defense mechanism in warty newts. However, variations in body size and the pressure of mammal predation might not play a significant role in determining aposematic coloration.


Assuntos
Pigmentação , Animais , Pigmentação/fisiologia , Masculino , Feminino , Comportamento Predatório/fisiologia , Mimetismo Biológico/fisiologia , Vietnã
3.
Bratisl Lek Listy ; 125(6): 392-398, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38757598

RESUMO

OBJECTIVES: This study aims to determine the malnutrition status among Vietnamese patients newly diagnosed with gastric cancer (GC). BACKGROUND: GC remains the top rank of common and deadly diseases. With limited clinical manifestation, most GC patients were diagnosed at late stages when tumor is not radically resected. Malnutrition was associated with poor prognosis of GC, such as prolonged hospitalization, limited treatment efficacy and low survival rate. METHODS: The cross-sectional descriptive study recruited 77 patients newly diagnosed with GC and 90 healthy individuals (HC). The data used for this study were approved by the local Ethical Committee. The data were analysed on STATA 14.0 and GraphPad Prism 8.0. RESULTS: We observed the male dominant distribution in GC cohort and over 65% of GC were firstly diagnosed at advanced stages (III and IV). Anemia was detected in about 50% of GC patients. Hyponutrition was prevalent in newly diagnosed GC. We found the decreased tendency of anemia related indexes from HC to early stages (I and II) and advanced stages (III and IV) of GC patients. CONCLUSION: Anemia and hypoproteinemia occurred frequently among Vietnamese newly diagnosed GC. The nutrition therapy would benefit GC patients (Tab. 4, Fig. 4, Ref. 20).


Assuntos
Anemia , Desnutrição , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Masculino , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Vietnã/epidemiologia , Anemia/diagnóstico , Anemia/etiologia , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Idoso , Adulto , Estadiamento de Neoplasias
4.
Microb Pathog ; 175: 105986, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36638852

RESUMO

In 2021, pomelo (Citrus grandi) trees grown in Tuyen Quang and Phu Tho in northern Vietnam suffered from leaf yellowing, gummosis on stems, brown rot on fruit, and black rot on roots. Based on morphological and sequence analysis of the ITS and cox1 gene regions, the pathogen causing gummosis and root rot of citrus trees was identified as Phytophthora parvispora. Pathogenicity assays using mycelial plugs and zoospore suspension showed that P. parvispora induces disease symptoms on both the upper and lower parts of various citrus trees, including pomelo, orange (C. sinensis), and lime (C. aurantiifolia). This is the first report of P. parvispora as the causative agent of gummosis and root rot on various citrus trees in South-East Asia as well as in Vietnam. Further, P. parvispora was sensitive to all tested fungicides, including mancozeb, chlorothalonil, fosetyl aluminium, potassium phosphonate, and dimethomorph. These findings will have important implications for the effective management of gummosis and root rot disease of citrus trees.


Assuntos
Citrus , Fungicidas Industriais , Phytophthora , Fungicidas Industriais/farmacologia , Phytophthora/genética , Árvores , Virulência
5.
J Nutr ; 153(1): 138-147, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36913447

RESUMO

BACKGROUND: Children and young adults with HIV infection may exhibit vitamin D deficiency, which is harmful to bone health as well as the endocrine and immune systems. OBJECTIVES: This study sought to investigate the effect of vitamin D supplementation on children and young adults with HIV infection. METHODS: The PubMed, Embase, and Cochrane databases were searched. Randomized controlled trials that have evaluated the effects of vitamin D supplementation (ergocalciferol or cholecalciferol) at any dose or for any duration in children and young adults with HIV infection, aged 0-25 y, were included. A random-effects model was used, and the standardized mean difference (SMD) and 95% CI were calculated. RESULTS: Ten trials, with 21 publications and 966 participants (mean age: 17.9 y), were included in the meta-analysis. The supplementation dose and the duration of the studies included ranged from 400 to 7000 IU/d and from 6 to 24 mo, respectively. Vitamin D supplementation was associated with a significantly higher serum 25(OH)D concentration at 12 mo (SMD: 1.14; 95% CI: 0.64, 1.65; P < 0.00001) compared with a placebo. No significant difference was observed in spine BMD (SMD: -0.09; 95% CI: -0.47, 0.3; P = 0.65) at 12 mo between these 2 groups. However, participants who received higher doses (1600-4000 IU/d) had significantly higher total BMD (SMD: 0.23; 95% CI: 0.02, 0.44; P = 0.03) and nonsignificantly higher spine BMD (SMD: 0.3; 95% CI: -0.02, 0.61; P = 0.07) at 12 mo compared with those who received standard doses (400-800 IU/d). CONCLUSIONS: Vitamin D supplementation in children and young adults with HIV infection increases the serum 25(OH)D concentration. A relatively high daily dose of vitamin D (1600-4000 IU) improves total BMD at 12 mo and results in sufficient 25(OH)D concentrations.


Assuntos
Infecções por HIV , Deficiência de Vitamina D , Humanos , Criança , Adulto Jovem , Adolescente , Infecções por HIV/complicações , Suplementos Nutricionais , Ensaios Clínicos Controlados Aleatórios como Assunto , Vitamina D , Colecalciferol , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/tratamento farmacológico
6.
Environ Res ; 231(Pt 1): 115984, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37156354

RESUMO

In the quest of improving the photocatalytic efficiency of photocatalysts, the combination of two and more semiconductors recently has garnered significant attention among scientists in the field. The doping of conductive metals is also an effective pathway to improve photocatalytic performance by avoiding electron/hole pair recombination and enhancing photon energy absorption. This work presented a design and fabrication of porphyrin@g-C3N4/Ag nanocomposite using acid-base neutralization-induced self-assembly approach from monomeric porphyrin and g-C3N4/Ag material. g-C3N4/Ag material was synthesized by a green reductant of Cleistocalyx operculatus leaf extract. Electron scanning microscopy (SEM), X-ray diffraction (XRD), FT-IR spectroscopy, and UV-vis spectrometer were utilized to analyse the properties of the prepared materials. The prepared porphyrin@g-C3N4/Ag nanocomposite showed well integration of porphyrin nanostructures on the g-C3N4/Ag's surface, in which porphyrin nanofiber was of the diameter in nanoscales and the length of several micrometers, and Ag NPs had an average particle size of less than 20 nm. The photocatalytic behavior of the resultant nanocomposite was tested for the degradation of Rhodamine B dye, which exhibited a remarkable RhB photodegrading percentage. The possible mechanism for photocatalysis of the porphyrin@g-C3N4/Ag nanocomposite toward Rhodamine B dye was also proposed and discussed.


Assuntos
Nanocompostos , Porfirinas , Espectroscopia de Infravermelho com Transformada de Fourier , Corantes , Elétrons
7.
BMC Public Health ; 23(1): 445, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882752

RESUMO

BACKGROUND: University students are vulnerable to changes due to COVID-19 pandemic. Although warning has been made about the impact of this crisis on students' mental health, there are barely any sufficient study. This work investigated how the pandemic affected the mental health of students at the Vietnam National University of Ho Chi Minh City (VNU-HCMC) and efficiency of available mental health supportive methods. METHODS: An online survey was conducted among students at Vietnam National University of Ho Chi Minh City (VNU-HCMC) from October 18, 2021, to October 25, 2021. Microsoft Excel 16.51 (Microsoft, USA) and R language, Epi packages 2.44 and 4.1.1 (rdrr.io) were used for data analysis. RESULTS: Thirty-seven thousand one hundred fifty students participated in the survey, including 48.4% female and 51.6% male. Online learning pressure was mainly recorded (65.1%). Many students suffered from sleeping disorders (56.2%). Some reported being victims of abuse (5.9%). Female students expressed a significantly higher level of distress than males, particularly the feeling of ambiguity about the purpose of life (p-value < 0.0001, OR: 0.94, 95% CI: [0.95-0.98]). Third-year students suffered higher stress levels than others, especially in online learning (68.8%, p-value < 0.05). Mental health statuses among students of different lockdown status regions were not significantly different. Therefore, lockdown status did not affect the stress levels of students which suggested that poor mental health outcomes seemed to root in the suspension of everyday university life rather than the prohibition of going out. CONCLUSIONS: During COVID-19, students experienced lots of stress and mental problems. These findings underscore the importance of academic and innovative activities, bringing attention to the needs of interactive study and extra-curricular activities.


Assuntos
COVID-19 , Saúde Mental , Estudantes , Feminino , Humanos , Masculino , Controle de Doenças Transmissíveis , COVID-19/epidemiologia , Estudos Transversais , Pandemias , População do Sudeste Asiático , Vietnã/epidemiologia , Estudantes/psicologia
8.
J Clin Lab Anal ; 37(15-16): e24958, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37621139

RESUMO

OBJECTIVE: To develop and validate an LC-M/SMS method for the determination of tacrolimus in human whole blood. METHOD: The LC-MS/MS method for the determination of tacrolimus in whole blood was developed and validated according to the guidelines. Concentrations of TAC in 100 kidney transplant patients measured by LC-MS/MS were compared with CMIA using correlation analysis and Bland-Altman plots. RESULTS: The method had a total chromatographic run time of 5 min. The calibration curves were linear over the range of 0.5-100.0 ng/mL with a lower limit of quantification of 1 ng/mL. The intra- and interday accuracy was within the range of 93.3%-109.2% and 96.0%-108.4%, respectively, with precision ranging from 0.8 to 9.4%. The mean extraction recoveries of TAC ranged from 102.6 to 107.8%. The mean concentrations of TAC in whole blood of kidney transplant patients measured by the two assays were different at 1, 3 months and all time points (p < 0.001), but no significant difference was observed at 6 months (p = 0.094). The correlation of data was good with the correlation coefficients (r2 ) of 0.7581, 0.8811, 0.8777, and 0.8077, respectively. Passing-Bablok regression analysis demonstrated good correlations with r2 values higher than 0.88 between TAC levels measured by LC-MS/MS and CMIA. Using Bland-Altman plots yielded average biases of 1.29, 0.79, 0.11, and 0.65 ng/mL at 1, 3, and 6 months and all time points. CONCLUSION: The LC-MS/MS method was validated for the accurate determination of TAC in human whole blood. The comparison of tacrolimus concentrations measured by the LC-MS/MS with CMIA showed a good correlation and agreement of two methods, suggesting LC-MS/MS should be used routinely to monitor TAC concentrations in kidney transplant patients.


Assuntos
Transplante de Rim , Tacrolimo , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Monitoramento de Medicamentos/métodos , Imunossupressores
9.
Mar Drugs ; 21(11)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37999380

RESUMO

Ulvan, a sulfated heteropolysaccharide with structural and functional properties of interest for various uses, was extracted from the green seaweed Ulva papenfussii. U. papenfussii is an unexplored Ulva species found in the South China Sea along the central coast of Vietnam. Based on dry weight, the ulvan yield was ~15% (w/w) and the ulvan had a sulfate content of 13.4 wt%. The compositional constitution encompassed L-Rhamnose (Rhap), D-Xylose (Xylp), D-Glucuronic acid (GlcAp), L-Iduronic acid (IdoAp), D-Galactose (Galp), and D-Glucose (Glcp) with a molar ratio of 1:0.19:0.35:0.52:0.05:0.11, respectively. The structure of ulvan was determined using High-Performance Liquid Chromatography (HPLC), Fourier Transform Infrared Spectroscopy (FT-IR), and Nuclear Magnetic Resonance spectroscopy (NMR) methods. The results showed that the extracted ulvan comprised a mixture of two different structural forms, namely ("A3s") with the repeating disaccharide [→4)-ß-D-GlcAp-(1→4)-α-L-Rhap 3S-(1→]n, and ("B3s") with the repeating disaccharide [→4)-α-L-IdoAp-(1→4)-α-L-Rhap 3S(1→]n. The relative abundance of A3s, and B3s was 1:1.5, respectively. The potential anticarcinogenic attributes of ulvan were evaluated against a trilogy of human cancer cell lineages. Concomitantly, Quantitative Structure-Activity Relationship (QSAR) modeling was also conducted to predict potential adverse reactions stemming from pharmacological interactions. The ulvan showed significant antitumor growth activity against hepatocellular carcinoma (IC50 ≈ 90 µg/mL), human breast cancer cells (IC50 ≈ 85 µg/mL), and cervical cancer cells (IC50 ≈ 67 µg/mL). The QSAR models demonstrated acceptable predictive power, and seven toxicity indications confirmed the safety of ulvan, warranting its candidacy for further in vivo testing and applications as a biologically active pharmaceutical source for human disease treatment.


Assuntos
Antineoplásicos , Clorófitas , Neoplasias , Ulva , Humanos , Ulva/química , Espectroscopia de Infravermelho com Transformada de Fourier , Polissacarídeos/farmacologia , Polissacarídeos/química , Clorófitas/química , Antineoplásicos/farmacologia , Dissacarídeos
10.
Int J Mol Sci ; 24(9)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37175852

RESUMO

The metabolic profile of the Aspergillus sp. 1901NT-1.2.2 sponge-associated fungal strain was investigated using the HPLC MS technique, and more than 23 peaks in the HPLC MS chromatogram were detected. Only two minor peaks were identified as endocrocin and terpene derivative MS data from the GNPS database. The main compound was isolated and identified as known anthraquinone derivative vismione E. The absolute stereochemistry of vismione E was established for the first time using ECD and quantum chemical methods. Vismione E showed high cytotoxic activity against human breast cancer MCF-7 cells, with an IC50 of 9.0 µM, in comparison with low toxicity for normal human breast MCF-10A cells, with an IC50 of 65.3 µM. It was found that vismione E inhibits MCF-7 cell proliferation and arrests the cell cycle in the G1 phase. Moreover, the negative influence of vismione E on MCF-7 cell migration was detected. Molecular docking of vismione E suggested the IMPDH2 enzyme as one of the molecular targets for this anthraquinone derivative.


Assuntos
Antineoplásicos , Poríferos , Animais , Humanos , Simulação de Acoplamento Molecular , Linhagem Celular Tumoral , Aspergillus , Fungos , Antineoplásicos/química , Antraquinonas/farmacologia , Estrutura Molecular
11.
Langmuir ; 38(30): 9285-9293, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35853180

RESUMO

Ultrasound-assisted extraction coupled with gas bubble flotation was developed as a green method for extracting ß-amyrin fromDischidia major. The solvent system was water:ethanol (9:1). To improve the adsorption of ß-amyrin onto the air/liquid interface during flotation, surfactants were employed; however, the positive effect was only observed with cationic surfactants. High-performance liquid chromatography with spectrophotometric detection (HPLC-PDA) was, for the first time, applied to quantify the ß-amyrin content in D. major and its extracts. With the assistance of surfactants, the foam layer collected from flotation showed high selectivity toward ß-amyrin. The product content was notably increased after surfactants had been removed from the solution.


Assuntos
Ácido Oleanólico , Tensoativos , Adsorção , Ácido Oleanólico/análogos & derivados , Solventes/química , Tensoativos/química
12.
AIDS Behav ; 26(4): 1095-1109, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34570314

RESUMO

Coronavirus disease 2019 (COVID-19) and associated social responses may uniquely affect people living with HIV (PLHIV). SARS-CoV-2 antibody testing and a cross-sectional survey on COVID-19's socio-behavioral impacts were conducted among a large PLHIV cohort in Hanoi, Vietnam. We examined anonymous antibody test results for 1243 PLHIV (99.8%) from whom plasma was obtained and completed surveys were collected in June/July 2020, just after the end of the first COVID-19 outbreak and nationwide lockdown. Three participants (0.2%) tested positive for anti-SARS-CoV-2 IgG antibodies. HIV treatment was generally maintained without antiretroviral therapy interruption, but COVID-19 had substantial impacts on economic security and risky health behaviors among PLHIV, which may have amplified psychological stress. These findings highlight the need for continuous monitoring of COVID-19's impacts on PLHIV and for efforts to mitigate these impacts.


Assuntos
COVID-19 , Infecções por HIV , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Continuidade da Assistência ao Paciente , Estudos Transversais , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Comportamentos de Risco à Saúde , Humanos , Saúde Mental , SARS-CoV-2 , Vietnã/epidemiologia
13.
Jpn J Clin Oncol ; 52(7): 707-715, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35383373

RESUMO

BACKGROUND: Colorectal cancer is a leading cancer incidence and cause of death worldwide and in Vietnam. Although screening is considered an effective measure to prevent and control colorectal cancer, there is no such effort in Vietnam. METHODS: Between 01 January 2018 and 31 October 2019, a population-based colorectal cancer screening program was conducted in Hanoi, Vietnam. A health advocacy campaign and follow-up phone calls were used to enroll residents aged ≥40 years old to complete an immunochemical-fecal occult blood testing. Positive immunochemical-fecal occult blood testing was followed by a colonoscopy. We also conducted a systematic review of the colorectal cancer screening programs in the Asia-Pacific region that used similar approach by searching Ovid Medline and PubMed databases. RESULTS: During study period, 103 542 individuals among 672 742 eligible residents attended the screening of whom 81.5% participants finished immunochemical-fecal occult blood testing test and the positive rate was 6.1%. The coverage rate for immunochemical-fecal occult blood testing test was 11.9%. Among 2278 individuals who underwent colonoscopy, 3.5% were histologically diagnosed with cancer, 17.8% with advanced adenomas, and 23.1% with non-advanced adenomas. Males had significantly higher detection rate of advanced adenomas, cancer or ≥ two polyps/tumor than females (P < 0.0001). The systematic review showed that in two-step modality (i.e. immunochemical-fecal occult blood testing/fecal immunochemical test and colonoscopy), the test positive was from 4.1 to 10.6%. Once colonoscopy was performed subsequently, the rate of cancer among positive participants was from 1.7 to 16.4% and that of advanced adenomas was from 7.1 to 23.1%. CONCLUSION: We showed that the two-step modality is a promising strategy for colorectal cancer screening in Vietnam that might apply to similar settings with limited resources.


Assuntos
Adenoma , Neoplasias Colorretais , Adenoma/diagnóstico , Adulto , Ásia , Colonoscopia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Detecção Precoce de Câncer , Feminino , Humanos , Masculino , Programas de Rastreamento , Sangue Oculto , Vietnã/epidemiologia
14.
Environ Res ; 206: 112631, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-34973199

RESUMO

TiO2 is a well-known semiconductor used widely in the photocatalyst field, but its photocatalytic applications are hampered by a fast electron-hole recombination rate and low visible light absorption due to a wide-band-gap energy. Herein, we present a simple, low cost, and green approach to obtain carbon dots from microalgae, namely microalgae-based carbon dots (MCDs), using an unprecedented microwave-assisted treatment. The MCDs were successfully decorated on the surface of TiO2 nanoparticles. The as-prepared composite exhibited a superior photodegradation of methylene blue, compared with pristine TiO2 (83% and 27%, respectively) under visible light irradiation. The MCDs in TiO2-MCDs serve as electron reservoirs to trap photoinduced electrons and as photosensitizers for the improvement of visible light absorption; both factors play an important role in the improvement of the TiO2 photocatalytic activity. Furthermore, the as-prepared composite photocatalyst also exhibits high photostability and recyclability during the photodegradation of methylene blue. Therefore, this work provides an original approach to the development of environmentally friendly and highly effective photocatalysts for the treatment of various organic pollutants, which can go a long way toward ensuring a safe and sustainable environment.


Assuntos
Microalgas , Nanopartículas , Carbono , Catálise , Fotólise , Titânio
15.
Nucleic Acids Res ; 48(19): 11068-11082, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33035335

RESUMO

tRNAs play a central role during the translation process and are heavily post-transcriptionally modified to ensure optimal and faithful mRNA decoding. These epitranscriptomics marks are added by largely conserved proteins and defects in the function of some of these enzymes are responsible for neurodevelopmental disorders and cancers. Here, we focus on the Trm11 enzyme, which forms N2-methylguanosine (m2G) at position 10 of several tRNAs in both archaea and eukaryotes. While eukaryotic Trm11 enzyme is only active as a complex with Trm112, an allosteric activator of methyltransferases modifying factors (RNAs and proteins) involved in mRNA translation, former studies have shown that some archaeal Trm11 proteins are active on their own. As these studies were performed on Trm11 enzymes originating from archaeal organisms lacking TRM112 gene, we have characterized Trm11 (AfTrm11) from the Archaeoglobus fulgidus archaeon, which genome encodes for a Trm112 protein (AfTrm112). We show that AfTrm11 interacts directly with AfTrm112 similarly to eukaryotic enzymes and that although AfTrm11 is active as a single protein, its enzymatic activity is strongly enhanced by AfTrm112. We finally describe the first crystal structures of the AfTrm11-Trm112 complex and of Trm11, alone or bound to the methyltransferase inhibitor sinefungin.


Assuntos
Proteínas Arqueais , Archaeoglobus fulgidus/enzimologia , RNA Arqueal/metabolismo , RNA de Transferência/metabolismo , tRNA Metiltransferases , Proteínas Arqueais/química , Proteínas Arqueais/metabolismo , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Conformação Proteica , Processamento de Proteína Pós-Traducional , tRNA Metiltransferases/química , tRNA Metiltransferases/metabolismo
16.
Mar Drugs ; 20(5)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35621956

RESUMO

Fucoidans are complex bioactive sulfated fucosyl-polysaccharides primarily found in brown macroalgae. Endo-fucoidanases catalyze the specific hydrolysis of α-L-fucosyl linkages in fucoidans and can be utilized to tailor-make fucoidan oligosaccharides and elucidate new structural details of fucoidans. In this study, an endo-α(1,3)-fucoidanase encoding gene, Mef2, from the marine bacterium Muricauda eckloniae, was cloned, and the Mef2 protein was functionally characterized. Based on the primary sequence, Mef2 was suggested to belong to the glycosyl hydrolase family 107 (GH107) in the Carbohydrate Active enZyme database (CAZy). The Mef2 fucoidanase showed maximal activity at pH 8 and 35 °C, although it could tolerate temperatures up to 50 °C. Ca2+ was shown to increase the melting temperature from 38 to 44 °C and was furthermore required for optimal activity of Mef2. The substrate specificity of Mef2 was investigated, and Fourier transform infrared spectroscopy (FTIR) was used to determine the enzymatic activity (Units per µM enzyme: Uf/µM) of Mef2 on two structurally different fucoidans, showing an activity of 1.2 × 10-3 Uf/µM and 3.6 × 10-3 Uf/µM on fucoidans from Fucus evanescens and Saccharina latissima, respectively. Interestingly, Mef2 was identified as the first described fucoidanase active on fucoidans from S. latissima. The fucoidan oligosaccharides released by Mef2 consisted of a backbone of α(1,3)-linked fucosyl residues with unique and novel α(1,4)-linked fucosyl branches, not previously identified in fucoidans from S. latissima.


Assuntos
Phaeophyceae , Hidrolases , Oligossacarídeos/química , Phaeophyceae/química , Polissacarídeos/química
17.
Mar Drugs ; 20(6)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35736183

RESUMO

Fucosylated chondroitin sulfates (FCSs) FCS-BA and FCS-HS, as well as fucan sulfates (FSs) FS-BA-AT and FS-HS-AT were isolated from the sea cucumbers Bohadschia argus and Holothuria (Theelothuria) spinifera, respectively. Purification of the polysaccharides was carried out by anion-exchange chromatography on DEAE-Sephacel column. Structural characterization of polysaccharides was performed in terms of monosaccharide and sulfate content, as well as using a series of non-destructive NMR spectroscopic methods. Both FCSs were shown to contain a chondroitin core [→3)-ß-d-GalNAc-(1→4)-ß-d-GlcA-(1→]n bearing sulfated fucosyl branches at O-3 of every GlcA residue in the chain. These fucosyl residues were different in pattern of sulfation: FCS-BA contained Fuc2S4S, Fuc3S4S and Fuc4S at a ratio of 1:8:2, while FCS-HS contained these residues at a ratio of 2:2:1. Polysaccharides differed also in content of GalNAc4S6S and GalNAc4S units, the ratios being 14:1 for FCS-BA and 4:1 for FCS-HS. Both FCSs demonstrated significant anticoagulant activity in clotting time assay and potentiated inhibition of thrombin, but not of factor Xa. FS-BA-AT was shown to be a regular linear polymer of 4-linked α-L-fucopyranose 3-sulfate, the structure being confirmed by NMR spectra of desulfated polysaccharide. In spite of considerable sulfate content, FS-BA-AT was practically devoid of anticoagulant activity. FS-HS-AT cannot be purified completely from contamination of some FCS. Its structure was tentatively represented as a mixture of chains identical with FS-BA-AT and other chains built up of randomly sulfated alternating 4- and 3-linked α-L-fucopyranose residues.


Assuntos
Holothuria , Pepinos-do-Mar , Animais , Anticoagulantes/química , Anticoagulantes/farmacologia , Sulfatos de Condroitina/química , Fucose/química , Holothuria/química , Polissacarídeos/farmacologia , Pepinos-do-Mar/química , Sulfatos/farmacologia
18.
J Mater Sci Mater Med ; 33(10): 72, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36195780

RESUMO

Hepatocellular carcinoma is a common type of cancer associated with a high mortality rate. Among several bioactive compounds, Murrayafoline A (MuA) has been proved as a bio substance that exhibits great potentials in treating liver cancer. In order to overcome the high cytotoxicity and low solubility of MuA, a delivery system based on nanocarriers is necessary to deliver MuA towards the desired target. In the present study, 18ß-glycyrrhetinic acid (GA), which is known as a ligand for liver targeting, was used to construct the cholesterol-poly (ethylene glycol)-glycyrrhetinic acid (GA-PEG-Chol) conjugate and liposome for MuA administration. The compound was then examined for therapeutic efficacy and safety in HUVEC and HepG2 cells in 2D and 3D cell cultures. Results have shown that MuA-loaded liposomes had IC50 value of 2 µM in HepG2 and had the cytosolic absorption of 8.83 ± 0.97 ng/105 cells, while The IC50 value of MuA-loaded liposomes in HUVEC cell lines was 15 µM and the the cytosolic absorption was recorded as 3.62 ± 0.61 cells. The drug test on the 3D cancer sphere platform of the HepG2 cancer sphere showed that MuA-loaded GA liposomes had the highest efficacy at a concentration of 100 µg/mL. In short, these results suggest that MuA-loaded GA liposomes have the potential for maintenance drug delivery and liver targeting.


Assuntos
Carcinoma Hepatocelular , Ácido Glicirretínico , Neoplasias Hepáticas , Alcaloides , Carbazóis , Carcinoma Hepatocelular/tratamento farmacológico , Colesterol , Ácido Glicirretínico/uso terapêutico , Células Hep G2 , Humanos , Ligantes , Lipossomos , Neoplasias Hepáticas/tratamento farmacológico
19.
Molecules ; 27(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36364472

RESUMO

The new polyketides lopouzanones A and B, as well as the new 1-O-acetyl and 2-O-acetyl derivatives of dendrodochol B, were isolated from the sponge-derived marine fungus Lopadostoma pouzarii strain 168CLC-57.3. Moreover, six known polyketides, gliorosein, balticolid, dendrodolide G, dihydroisocoumarine, (-)-5-methylmellein, and dendrodochol B, were identified. The structures of the isolated compounds were determined by a combination of NMR and ESIMS techniques. The absolute configurations of the lopouzanones A and B were determined using the Mosher's method. The cytotoxicity of the isolated compounds against human prostate cancer cells PC-3 and normal rat cardiomyocytes H9c2 was investigated. Gliorosein showed weak DPPH radical-scavenging activity and in vitro cardioprotective effects toward rotenone toxicity and CoCl2-mimic hypoxia.


Assuntos
Ascomicetos , Policetídeos , Humanos , Ratos , Animais , Policetídeos/química , Ascomicetos/química , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular
20.
Cancer Control ; 28: 1073274821989320, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33517745

RESUMO

BACKGROUND: Data about the risk factors and pancreatic cancer in developing countries remain limited. We investigated for the first time the role of a number of risk factors (family cancer history, smoking, alcohol consumption, diabetes, inflammation disease, HBV infection) associated with pancreatic cancer among Vietnamese patients. METHODS: We included all patients hospitalized at 4 Northern Vietnamese hospitals (Vietnam National Cancer Hospital, Bach Mai, Viet Duc, Thai Nguyen) and diagnosed with pancreatic cancer during the period from 2017 to 2019. Risk factors of eligible patients were collected and assessed the associations using a matched control study and logistic regression model analysis. RESULTS: We identified 196 patients with diagnosis of pancreatic cancer of which 114 males and 82 females. The average age of the patient at the time of diagnosis was 58.28 years (standard deviation of 12.94, ranging from 25 to 87). Most of patients were diagnosed at advanced stage (85%). Smoking, diabetes, inflammation disease significantly increased the cancer risks (OR and 95% CI were 2.42 (1.38-4.37), 3.09 (1.54-6.68), 2.21 (1.42-3.45), respectively). HBV infection demonstrated a significant link with pancreatic cancer in univariate model (OR = 2.94 (1.08-9.36)), but not in multivariate model. However, cancer family history and alcohol drinkers did not show any significantly increased risk related to pancreatic cancer. CONCLUSIONS: Our finding showed smoking, diabetes, inflammation disease significantly increased the risk of pancreatic cancer in Vietnam.


Assuntos
Complicações do Diabetes , Neoplasias Pancreáticas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/efeitos adversos , Estudos de Casos e Controles , Países em Desenvolvimento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/etiologia , Fatores de Risco , Fumar/efeitos adversos , Vietnã
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