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1.
J Transl Med ; 22(1): 498, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38796431

RESUMO

OBJECTIVE: The aim of the present pilot study was to assess the effectiveness of the platelet-rich fibrin (PRF) apical barrier for the placement of MTA for the treatment of teeth with periapical lesions and open apices. METHODS: A total of thirty teeth on twenty-eight patients with open apices and periapical periodontitis were enrolled and divided into two groups in the present pilot study. In the PRF group (fourteen teeth in thirteen patients), nonsurgical endodontic treatment was performed using PRF as an apical matrix, after which the apical plug of the MTA was created. For the non-PRF group (fourteen teeth in fourteen patients), nonsurgical endodontic therapy was performed using only the MTA for an apical plug with no further periapical intervention. Clinical findings and periapical digital radiographs were used for evaluating the healing progress after periodic follow-ups of 1, 3, 6, and 9 months. The horizontal dimension of the periapical lesion was gauged, and the changes in the dimensions were recorded each time. The Friedman test, Dunn-Bonferroni post hoc correction, and Mann-Whitney U test were used for statistical analysis, with P < 0.05 serving as the threshold for determining statistical significance. RESULTS: All patients in both groups in the present pilot study had no clinical symptoms after 1 month, with a significant reduction in the periapical lesion after periodic appointments. The lesion width of the PRF group was significantly smaller than that of the non-PRF group in the sixth and ninth month after treatment. CONCLUSIONS: PRF is a promising apical barrier matrix when combined with MTA for the treatment of teeth with open apices and periapical periodontitis. Small number of study subjects and the short time of follow-up period limit the generalizability of these results. TRIAL REGISTRATION: TCTR, TCTR20221109006. Registered 09 November 2022 - Retrospectively registered, https://www.thaiclinicaltrials.org/show/TCTR20221109006 .


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Fibrina Rica em Plaquetas , Silicatos , Ápice Dentário , Humanos , Projetos Piloto , Fibrina Rica em Plaquetas/metabolismo , Feminino , Masculino , Compostos de Alumínio/uso terapêutico , Silicatos/uso terapêutico , Compostos de Cálcio/uso terapêutico , Adulto , Ápice Dentário/patologia , Ápice Dentário/diagnóstico por imagem , Combinação de Medicamentos , Pessoa de Meia-Idade , Óxidos/uso terapêutico , Periodontite Periapical/terapia , Periodontite Periapical/diagnóstico por imagem
2.
Cardiovasc Diabetol ; 23(1): 197, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849829

RESUMO

OBJECTIVE: Sodium glucose cotransporter 2 (SGLT2) inhibitors significantly improve cardiovascular outcomes in diabetic patients; however, the mechanism is unclear. We hypothesized that dapagliflozin improves cardiac outcomes via beneficial effects on systemic and cardiac inflammation and cardiac fibrosis. RESEARCH AND DESIGN METHODS: This randomized placebo-controlled clinical trial enrolled 62 adult patients (mean age 62, 17% female) with type 2 diabetes (T2D) without known heart failure. Subjects were randomized to 12 months of daily 10 mg dapagliflozin or placebo. For all patients, blood/plasma samples and cardiac magnetic resonance imaging (CMRI) were obtained at time of randomization and at the end of 12 months. Systemic inflammation was assessed by plasma IL-1B, TNFα, IL-6 and ketone levels and PBMC mitochondrial respiration, an emerging marker of sterile inflammation. Global myocardial strain was assessed by feature tracking; cardiac fibrosis was assessed by T1 mapping to calculate extracellular volume fraction (ECV); and cardiac tissue inflammation was assessed by T2 mapping. RESULTS: Between the baseline and 12-month time point, plasma IL-1B was reduced (- 1.8 pg/mL, P = 0.003) while ketones were increased (0.26 mM, P = 0.0001) in patients randomized to dapagliflozin. PBMC maximal oxygen consumption rate (OCR) decreased over the 12-month period in the placebo group but did not change in patients receiving dapagliflozin (- 158.9 pmole/min/106 cells, P = 0.0497 vs. - 5.2 pmole/min/106 cells, P = 0.41), a finding consistent with an anti-inflammatory effect of SGLT2i. Global myocardial strain, ECV and T2 relaxation time did not change in both study groups. GOV REGISTRATION: NCT03782259.


Assuntos
Compostos Benzidrílicos , Biomarcadores , Diabetes Mellitus Tipo 2 , Glucosídeos , Mediadores da Inflamação , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Compostos Benzidrílicos/uso terapêutico , Compostos Benzidrílicos/efeitos adversos , Glucosídeos/uso terapêutico , Glucosídeos/efeitos adversos , Feminino , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Masculino , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Pessoa de Meia-Idade , Idoso , Resultado do Tratamento , Mediadores da Inflamação/sangue , Biomarcadores/sangue , Fatores de Tempo , Anti-Inflamatórios/uso terapêutico , Fibrose , Inflamação/tratamento farmacológico , Inflamação/sangue , Inflamação/diagnóstico , Método Duplo-Cego , Miocárdio/patologia , Miocárdio/metabolismo , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/prevenção & controle , Cardiomiopatias Diabéticas/diagnóstico por imagem , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/sangue
3.
Emerg Infect Dis ; 29(5): 1002-1006, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37015283

RESUMO

We analyzed 1,303 SARS-CoV-2 whole-genome sequences from Vietnam, and found the Alpha and Delta variants were responsible for a large nationwide outbreak of COVID-19 in 2021. The Delta variant was confined to the AY.57 lineage and caused >1.7 million infections and >32,000 deaths. Viral transmission was strongly affected by nonpharmaceutical interventions.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , SARS-CoV-2/genética , Vietnã/epidemiologia , Surtos de Doenças
4.
J Infect Chemother ; 28(12): 1632-1638, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36049613

RESUMO

BACKGROUND: Ventilator-associated pneumonia (VAP) has emerged as a critical issue in the intensive care unit (ICU) because of its high burden on patients and medical staff. Here, we examined the potential for reducing VAP incidence through physical oral care interventions without any medication. METHODS: This prospective interventional study compared VAP incidence during an 8-month baseline period (usual oral care) and a 9-month intervention period (physical oral care with sponge brush) among patients who received mechanical ventilation for >48 h in a tertiary care hospital in Vietnam from 2017 to 2019. Physical oral care was provided by general ICU nurses who had been trained by dentists and infection control nurses. VAP was diagnosed using the Clinical Pulmonary Infection Score. RESULTS: In total, 423 patients were enrolled in the baseline group and 454 patients were enrolled in the intervention group; 303 and 300 patients, respectively, were included in the analysis. Two hundred thirty-eight VAP episodes were identified: 135 (44.6%) during the baseline period and 103 (34.3%) during the intervention period. Univariate analysis revealed significant reduction of VAP occurrence in the intervention period (odds ratio = 0.65; 95% confidence interval = 0.47-0.90; P = 0.010). The incidences of VAP per 1000 ventilator-days were 63.4 (135/2128) during the baseline period and 48.4 (103/2128) during the intervention period (P = 0.038). CONCLUSIONS: Physical oral care without any medication (e.g., chlorhexidine) reduced VAP incidence in the ICU. This method could be used to reduce VAP incidence, particularly in countries with limited medical resources.


Assuntos
Pneumonia Associada à Ventilação Mecânica , Clorexidina/uso terapêutico , Humanos , Incidência , Unidades de Terapia Intensiva , Pneumonia Associada à Ventilação Mecânica/tratamento farmacológico , Pneumonia Associada à Ventilação Mecânica/epidemiologia , Pneumonia Associada à Ventilação Mecânica/prevenção & controle , Estudos Prospectivos , Respiração Artificial/efeitos adversos , Vietnã/epidemiologia
5.
Chem Biodivers ; 19(4): e202100882, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35146904

RESUMO

Four compounds, luteolin (1), 6-γ,γ-dimethylallylquercetin 7-O-ß-D-glucopyranoside (2), 6-γ,γ-dimethylallylkaempferol 7-O-ß-D-glucopyranoside (3), and 6-γ,γ-dimethylallyldihydrokaempferol 7-O-ß-D-glucoside (4), were isolated for the first time from AcOEt extract of the O. integerrima flower. We then evaluated the antioxidant effects of AcOEt, butanol, and MeOH extracts and their effects on H2 O2 against oxidative stress in HaCaT keratinocyte cell lines. Furthermore, 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH⋅) radical scavenging activities of 1-4 were determined and their mechanisms of action on tyrosinase were predicted by in silico studies. The results revealed that the AcOEt extract and 1-3 exhibited good DPPH⋅ radical scavenging activity. Furthermore, this extract also had a significant protective effect against H2 O2 -induced oxidative stress in HaCaT cells. In silico studies indicated that the activity of 1-3 may be due to tyrosinase inhibition with MM-GBSA free binding energies of -78.9, -70.1, and -71.1 kcal mol-1 , respectively, compared to 4 with an energy -56.9 kcal mol-1 .


Assuntos
Antioxidantes , Ochnaceae , Antioxidantes/química , Antioxidantes/farmacologia , Flores , Queratinócitos , Monofenol Mono-Oxigenase , Extratos Vegetais/química , Extratos Vegetais/farmacologia
6.
Int J Forecast ; 38(3): 1129-1157, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035005

RESUMO

We develop a variant of intervention analysis designed to measure a change in the law of motion for the distribution of individuals in a cross-section, rather than modeling the moments of the distribution. To calculate a counterfactual forecast, we discretize the distribution and employ a Markov model in which the transition probabilities are modeled as a multinomial logit distribution. Our approach is scalable and is designed to be applied to micro-level data. A wide panel often carries with it several imperfections that complicate the analysis when using traditional time-series methods; our framework accommodates these imperfections. The result is a framework rich enough to detect intervention effects that not only shift the mean, but also those that shift higher moments, while leaving lower moments unchanged. We apply this framework to document the changes in credit usage of consumers during the COVID-19 pandemic. We consider multinomial logit models of the dependence of credit-card balances, with categorical variables representing monthly seasonality, homeownership status, and credit scores. We find that, relative to our forecasts, consumers have greatly reduced their use of credit. This result holds for homeowners and renters as well as consumers with both high and low credit scores.

7.
Can J Econ ; 55(Suppl 1): 88-114, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38607843

RESUMO

The recent COVID-19 pandemic has devastated economies worldwide. Using detailed, monthly data from a major consumer credit reporting agency in Canada, we have examined individuals' use of credit cards and home-equity lines of credit (HELOCs). We found a dramatic leftward shift in the distribution of credit card and HELOC outstanding balances, providing evidence for a widespread reduction in credit usage. Our findings suggest that, during the COVID-19 recession, Canadian consumers were able to meet their financial needs without increasing their debt burdens. These results complement other findings concerning a decline in consumer spending and the results of government assistance programs, and imply that the economic consequences of this pandemic are very different from those in other recessions.


Recours au crédit à la consommation au Canada au cours de la pandémie de coronavirus. La récente pandémie de COVID­19 a ravagé les économies mondiales. Grâce aux données mensuelles détaillées d'une des agences d'évaluation du crédit les plus importantes du pays, nous avons examiné le recours aux cartes de crédit et aux marges de crédit hypothécaires des Canadiens. Sur les figures illustrant la distribution des soldes impayés de cartes de crédit et de marges de crédit hypothécaires, nous constatons un important déplacement vers la gauche, ce qui reflète un fléchissement généralisé du recours au crédit. Nos résultats suggèrent qu'au cours de la récession provoquée par la COVID­19, les consommateurs canadiens ont pu satisfaire leurs besoins financiers sans alourdir leurs dettes. Ces conclusions complètent d'autres observations, notamment sur la baisse des dépenses de consommation ou sur l'effet des programmes d'aide du gouvernement, et laissent entendre que les conséquences économiques de cette pandémie sont très différentes de celles observées dans d'autres types de récession.

9.
J Nanobiotechnology ; 19(1): 73, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712008

RESUMO

BACKGROUND: Blood prostate-specific antigen (PSA) levels are widely used as diagnostic biomarkers for prostate cancer. Lateral-flow immunoassay (LFIA)-based PSA detection can overcome the limitations associated with other methods. LFIAbased PSA detection in clinical samples enables prognosis and early diagnosis owing to the use of high-performance signal reporters. RESULTS: Here, a semiquantitative LFIA platform for PSA detection in blood was developed using Au-Ag nanoparticles (NPs) assembled on silica NPs (SiO2@Au-Ag NPs) that served as signal reporters. Synthesized SiO2@Au-Ag NPs exhibited a high absorbance at a wide wavelength range (400-800 nm), with a high scattering on nitrocellulose membrane test strips. In LFIA, the color intensity of the test line on the test strip differed depending on the PSA concentration (0.30-10.00 ng/mL), and bands for the test line on the test strip could be used as a standard. When clinical samples were assessed using this LFIA, a visual test line with particular color intensity observed on the test strip enabled the early diagnosis and prognosis of patients with prostate cancer based on PSA detection. In addition, the relative standard deviation of reproducibility was 1.41%, indicating high reproducibility, and the signal reporter showed good stability for 10 days. CONCLUSION: These characteristics of the signal reporter demonstrated the reliability of the LFIA platform for PSA detection, suggesting potential applications in clinical sample analysis.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Antígeno Prostático Específico/sangue , Antígeno Prostático Específico/isolamento & purificação , Neoplasias da Próstata/diagnóstico , Dióxido de Silício/química , Prata/química , Técnicas Biossensoriais/métodos , Colorimetria , Humanos , Imunoensaio/métodos , Limite de Detecção , Masculino , Reprodutibilidade dos Testes
10.
Adv Exp Med Biol ; 1309: 235-255, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33782875

RESUMO

Nanobiotechnology is known as the application of nanoscaled techniques in biology which bridges natural science to living organism for improving the quality of life of humans. Nanotechnology was first issued in 1959 and has been rapidly developed, supplying numerous benefits to basic scientific academy and to clinical application including human healthcare, specifically in cancer therapy. This chapter discusses recent advances and potentials of nanotechnology in pharmaceutics, therapeutics, biosensing, bioimaging, and gene delivery that demonstrate the multifunctionality of nanotechnology.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Humanos , Nanomedicina , Nanotecnologia , Qualidade de Vida
11.
Chem Biodivers ; 18(12): e2100499, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34761862

RESUMO

A new natural Diels-Alder adduct (3) was isolated from the leaves and stem bark of Artocarpus integer, along with seventeen known compounds (1, 2, and 4-18). Structural elucidation was conducted using NMR and HR-ESI-MS data, and comparisons were made with previous studies. Deoxyartonin I (3) exhibited the most potent α-glucosidase inhibition (IC50 7.80±0.1 µM), outperforming the acarbose positive control. This was mixed-mode inhibition, as indicated by the intersect in the second quadrant of each respective plot. An in silico molecular docking model and the pharmacokinetic features of 3 suggest that it is a potential inhibitor of enzyme α-glucosidase, and is therefore a lead candidate as a drug against diabetes mellitus.


Assuntos
Artocarpus/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , alfa-Glucosidases/metabolismo , Relação Dose-Resposta a Droga , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Humanos , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
12.
Int J Mol Sci ; 22(5)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802614

RESUMO

In this study, dense gold-assembled SiO2 nanostructure (SiO2@Au) was successfully developed using the Au seed-mediated growth. First, SiO2 (150 nm) was prepared, modified by amino groups, and incubated by gold nanoparticles (ca. 3 nm Au metal nanoparticles (NPs)) to immobilize Au NPs to SiO2 surface. Then, Au NPs were grown on the prepared SiO2@Au seed by reducing chloroauric acid (HAuCl4) by ascorbic acid (AA) in the presence of polyvinylpyrrolidone (PVP). The presence of bigger (ca. 20 nm) Au NPs on the SiO2 surface was confirmed by transmittance electronic microscopy (TEM) images, color changes to dark blue, and UV-vis spectra broadening in the range of 450 to 750 nm. The SiO2@Au nanostructure showed several advantages compared to the hydrofluoric acid (HF)-treated SiO2@Au, such as easy separation, surface modification stability by 11-mercaptopundecanoic acid (R-COOH), 11-mercapto-1-undecanol (R-OH), and 1-undecanethiol (R-CH3), and a better peroxidase-like catalysis activity for 5,5'-Tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2) reaction. The catalytic activity of SiO2@Au was two times better than that of HF-treated SiO2@Au. When SiO2@Au nanostructure was used as a surface enhanced Raman scattering (SERS) substrate, the signal of 4-aminophenol (4-ATP) on the surface of SiO2@Au was also stronger than that of HF-treated SiO2@Au. This study provides a potential method for nanoparticle preparation which can be replaced for Au NPs in further research and development.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Nanoestruturas/química , Dióxido de Silício/química , Aminofenóis/química , Benzidinas/química , Técnicas Biossensoriais/métodos , Catálise , Ácido Fluorídrico/química , Peróxido de Hidrogênio/química , Limite de Detecção , Povidona/química , Prata/química , Compostos de Sulfidrila/química
13.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204265

RESUMO

Human epidermal growth factor receptor 2 (HER-2) is overexpressed in many malignant tumors. The anti-HER2 antibody trastuzumab has been approved for treating HER2-positive early and metastatic breast cancers. Pseudomonas exotoxin A (PE), a bacterial toxin of Pseudomonas aeruginosa, consists of an A-domain with enzymatic activity and a B-domain with cell binding activity. Recombinant immunotoxins comprising the HER2(scFv) single-chain Fv from trastuzumab and the PE24B catalytic fragment of PE display promising cytotoxic effects, but immunotoxins are typically insoluble when expressed in the cytoplasm of Escherichia coli, and thus they require solubilization and refolding. Herein, a recombinant immunotoxin gene was fused with maltose binding protein (MBP) and overexpressed in a soluble form in E. coli. Removal of the MBP yielded stable HER2(scFv)-PE24B at 91% purity; 0.25 mg of pure HER2(scFv)-PE24B was obtained from a 500 mL flask culture. Purified HER2(scFv)-PE24B was tested against four breast cancer cell lines differing in their surface HER2 level. The immunotoxin showed stronger cytotoxicity than HER2(scFv) or PE24B alone. The IC50 values for HER2(scFv)-PE24B were 28.1 ± 2.5 pM (n = 9) and 19 ± 1.4 pM (n = 9) for high HER2-positive cell lines SKBR3 and BT-474, respectively, but its cytotoxicity was lower against MDA-MB-231 and MCF7. Thus, fusion with MBP can facilitate the soluble expression and purification of scFv immunotoxins.


Assuntos
ADP Ribose Transferases , Antineoplásicos Imunológicos/farmacologia , Toxinas Bacterianas , Exotoxinas , Imunotoxinas/farmacologia , Proteínas Ligantes de Maltose , Receptor ErbB-2/antagonistas & inibidores , Proteínas Recombinantes de Fusão/farmacologia , Anticorpos de Cadeia Única , Fatores de Virulência , ADP Ribose Transferases/genética , Toxinas Bacterianas/genética , Linhagem Celular Tumoral , Sobrevivência Celular , Relação Dose-Resposta a Droga , Escherichia coli/genética , Escherichia coli/metabolismo , Exotoxinas/genética , Expressão Gênica , Engenharia Genética , Vetores Genéticos/genética , Humanos , Imunotoxinas/genética , Imunotoxinas/isolamento & purificação , Proteínas Ligantes de Maltose/genética , Espectrometria de Massas , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Anticorpos de Cadeia Única/genética , Fatores de Virulência/genética , Exotoxina A de Pseudomonas aeruginosa
14.
Int J Mol Sci ; 22(10)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067755

RESUMO

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a member of the colony-stimulating factor (CSF) family, which functions to enhance the proliferation and differentiation of hematopoietic stem cells and other hematopoietic lineages such as neutrophils, dendritic cells, or macrophages. These proteins have thus generated considerable interest in clinical therapy research. A current obstacle to the prokaryotic production of human GM-CSF (hGM-CSF) is its low solubility when overexpressed and subsequent complex refolding processes. In our present study, the solubility of hGM-CSF was examined when combined with three N-terminal fusion tags in five E. coli strains at three different expression temperatures. In the five E. coli strains BL21 (DE3), ClearColi BL21 (DE3), LOBSTR, SHuffle T7 and Origami2 (DE3), the hexahistidine-tagged hGM-CSF showed the best expression but was insoluble in all cases at each examined temperature. Tagging with the maltose-binding protein (MBP) and the b'a' domain of protein disulfide isomerase (PDIb'a') greatly improved the soluble overexpression of hGM-CSF at 30 °C and 18 °C. The solubility was not improved using the Origami2 (DE3) and SHuffle T7 strains that have been engineered for disulfide bond formation. Two conventional chromatographic steps were used to purify hGM-CSF from the overexpressed PDIb'a'-hGM-CSF produced in ClearColi BL21 (DE3). In the experiment, 0.65 mg of hGM-CSF was isolated from a 0.5 L flask culture of these E. coli and showed a 98% purity by SDS-PAGE analysis and silver staining. The bioactivity of this purified hGM-CSF was measured at an EC50 of 16.4 ± 2 pM by a CCK8 assay in TF-1 human erythroleukemia cells.


Assuntos
Cromatografia em Gel/métodos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/isolamento & purificação , Isomerases de Dissulfetos de Proteínas/metabolismo , Diferenciação Celular , Eletroforese em Gel de Poliacrilamida/métodos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Humanos , Proteínas Ligantes de Maltose/metabolismo , Células Procarióticas/metabolismo , Isomerases de Dissulfetos de Proteínas/fisiologia , Transporte Proteico , Solubilidade
15.
Int J Mol Sci ; 22(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198626

RESUMO

Human stem-cell factor (hSCF) stimulates the survival, proliferation, and differentiation of hematopoietic cells by binding to the c-Kit receptor. Various applications of hSCF require the efficient and reliable production of hSCF. hSCF exists in three forms: as two membrane-spanning proteins hSCF248 and hSCF229 and truncated soluble N-terminal protein hSCF164. hSCF164 is known to be insoluble when expressed in Escherichia coli cytoplasm, requiring a complex refolding procedure. The activity of hSCF248 has never been studied. Here, we investigated novel production methods for recombinant hSCF164 and hSCF248 without the refolding process. To increase the solubility of hSCF164, maltose-binding protein (MBP) and protein disulfide isomerase b'a' domain (PDIb'a') tags were attached to the N-terminus of hSCF164. These fusion proteins were overexpressed in soluble form in the Origami 2(DE3) E. coli strain. These solubilization effects were enhanced at a low temperature. His-hSCF248, the poly-His tagged form of hSCF248, was expressed in a highly soluble form without a solubilization tag protein, which was unexpected because His-hSCF248 contains a transmembrane domain. hSCF164 was purified using affinity and ion-exchange chromatography, and His-hSCF248 was purified by ion-exchange and gel filtration chromatography. The purified proteins stimulated the proliferation of TF-1 cells. Interestingly, the EC50 value of His-hSCF248 was 1 pg/mL, 100-fold lower than 9 ng/mL hSCF164. Additionally, His-hSCF248 decreased the doubling time, increased the proportion of S and G2/M stages in the cell cycle, and increased the c-Myc expression at a 1000-fold lower concentration than hSCF164. In conclusion, His-hSCF248 was expressed in a soluble form in E. coli and had stronger activity than hSCF164. The molecular chaperone, MBP, enabled the soluble overexpression of hSCF164.


Assuntos
Fator de Células-Tronco/biossíntese , Sequência de Aminoácidos , Ciclo Celular , Proliferação de Células , Regulação da Expressão Gênica , Humanos , Plasmídeos/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Solubilidade , Fator de Células-Tronco/química
16.
Molecules ; 26(17)2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34500805

RESUMO

Panax vietnamensis, or Vietnamese ginseng (VG), an endemic Panax species in Vietnam, possesses a unique saponin profile and interesting biological activities. This plant is presently in danger of extinction due to over-exploitation, resulting in many preservation efforts towards the geographical acclimatization of VG. Yet, no information on the saponin content of the acclimatized VG, an important quality indicator, is available. Here, we analyzed the saponin content in the underground parts of two- to five-year-old VG plants acclimatized to Lam Dong province. Nine characteristic saponins, including notoginsenoside-R1, ginsenoside-Rg1, -Rb1, -Rd, majonoside-R1, -R2 vina-ginsenoside-R2, -R11, and pseudoginsenoside-RT4, were simultaneously determined by HPLC coupled with UV and with a charged aerosol detector (CAD). Analyzing the results illustrated that the detection of characteristic ocotillol-type saponins in VG by CAD presented a superior capacity compared with that of UV, thus implying a preferential choice of CAD for the analysis of VG. The quantitative results indicating the saponin content in the underground parts of VG showed an increasing tendency from two to five years old, with the root and the rhizome exhibiting different saponin accumulation patterns. This is the first study that reveals the preliminary success of VG acclimatization and thereby encourages the continuing efforts to develop this valuable saponin-rich plant.


Assuntos
Panax/química , Saponinas/análise , Cromatografia Líquida de Alta Pressão , Raios Ultravioleta , Vietnã
17.
BMC Med ; 18(1): 364, 2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33243267

RESUMO

BACKGROUND: In dengue-endemic countries, targeting limited control interventions to populations at risk of severe disease could enable increased efficiency. Individuals who have had their first (primary) dengue infection are at risk of developing more severe secondary disease, thus could be targeted for disease prevention. Currently, there is no reliable algorithm for determining primary and post-primary (infection with more than one flavivirus) status from a single serum sample. In this study, we developed and validated an immune status algorithm using single acute serum samples from reporting patients and investigated dengue immuno-epidemiological patterns across the Philippines. METHODS: During 2015/2016, a cross-sectional sample of 10,137 dengue case reports provided serum for molecular (anti-DENV PCR) and serological (anti-DENV IgM/G capture ELISA) assay. Using mixture modelling, we re-assessed IgM/G seroprevalence and estimated functional, disease day-specific, IgG:IgM ratios that categorised the reporting population as negative, historical, primary and post-primary for dengue. We validated our algorithm against WHO gold standard criteria and investigated cross-reactivity with Zika by assaying a random subset for anti-ZIKV IgM and IgG. Lastly, using our algorithm, we explored immuno-epidemiological patterns of dengue across the Philippines. RESULTS: Our modelled IgM and IgG seroprevalence thresholds were lower than kit-provided thresholds. Individuals anti-DENV PCR+ or IgM+ were classified as active dengue infections (83.1%, 6998/8425). IgG- and IgG+ active dengue infections on disease days 1 and 2 were categorised as primary and post-primary, respectively, while those on disease days 3 to 5 with IgG:IgM ratios below and above 0.45 were classified as primary and post-primary, respectively. A significant proportion of post-primary dengue infections had elevated anti-ZIKV IgG inferring previous Zika exposure. Our algorithm achieved 90.5% serological agreement with WHO standard practice. Post-primary dengue infections were more likely to be older and present with severe symptoms. Finally, we identified a spatio-temporal cluster of primary dengue case reporting in northern Luzon during 2016. CONCLUSIONS: Our dengue immune status algorithm can equip surveillance operations with the means to target dengue control efforts. The algorithm accurately identified primary dengue infections who are at risk of future severe disease.


Assuntos
Vírus da Dengue/patogenicidade , Dengue/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Masculino , Filipinas , Adulto Jovem
18.
Rev Med Virol ; 29(1): e2011, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30306730

RESUMO

Maternofetal transmission of cytomegalovirus (CMV) is the most common infectious cause of congenital malformation in developed countries. Maternal infection often results from close contact with infected children, and this may occur in day care centres (DCCs). A systematic review of observational studies was conducted to examine the prevalence of CMV infection among children attending DCCs. Meta-analysis using the random effect model was performed for studies including controls. Sources included PubMed, EMBASE (until August 2018), and references from identified publications. Inclusion criteria were studies reporting CMV infection prevalence among childcare children aged less than 7 years of age. Controls were children without childcare exposure. CMV infection was defined as viral excretion detected by culture, polymerase chain reaction, or CMV seropositivity. Twenty-eight publications including 8347 participants met the eligibility criteria. The pooled prevalence of CMV infection among children in childcare from all studies was 32% (95% CI 23-41). Within case-controlled studies, prevalence among children attending DCCs was 34% (95% CI 25-44), whereas prevalence among those without childcare exposure was 22% (95% CI 15-30). Meta-analysis showed a significant association between DCC attendance and CMV infection (odds ratio 2.69, 95% CI 1.68-4.30; heterogeneity χ2 /df = 8; I2  = 84%, P < 0.00001). Attendance at DCCs is significantly associated with increased risk of childhood CMV infection. Prevention strategies to reduce risk of CMV infection of pregnant women and children should involve review of DCC exposure and consideration of preventative hygiene strategies.


Assuntos
Creches , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/transmissão , Citomegalovirus/isolamento & purificação , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Controle de Infecções/métodos , Prevalência
19.
Chem Biodivers ; 17(5): e2000037, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32163220

RESUMO

The ocotillol (OCT)-type saponins have been known as a tetracyclic triterpenoid, possessing five- or six-membered epoxy ring in the side chain. Interestingly, this type saponin was mostly found in Panax vietnamensis Ha et Grushv., Araliaceae (VG), hence making VG unique from the other Panax spp. Five OCT-type saponins, majonoside R2, vina-ginsenoside R2, majonoside R1, pseudoginsenoside RT4, vina-ginsenoside R11, together with three protopanaxadiol (PPD)-type saponins and four protopanaxatriol (PPT)-type saponins from VG were evaluated for their antimelanogenic activity. All of isolates were found to be active. More importantly, the five OCT-type saponins inhibited melanin production in B16-F10 mouse melanoma cells, without showing any cytotoxicity. Besides ginsenoside Rd and ginsenoside Rg3 in PPD and notoginsenoside R1 in PPT-type saponins, majonoside R2 was the most potent melanogenesis inhibitory activity in OCT-type saponins. In this article, we highlighted antimelanogenic activity of OCT-type saponins and potential structure-activity relationship (SAR) of ginsenosides. Our results suggested that OCT-type saponins could be used as a depigmentation agent.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Ginsenosídeos/farmacologia , Melanoma/tratamento farmacológico , Panax/química , Saponinas/farmacologia , Animais , Antineoplásicos Imunológicos/química , Antineoplásicos Imunológicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ginsenosídeos/química , Ginsenosídeos/isolamento & purificação , Melaninas/antagonistas & inibidores , Melaninas/metabolismo , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Conformação Molecular , Plantas Medicinais , Saponinas/química , Saponinas/isolamento & purificação , Relação Estrutura-Atividade , Células Tumorais Cultivadas
20.
Int J Mol Sci ; 21(14)2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32708351

RESUMO

Metallic alloy nanoparticles are synthesized by combining two or more different metals. Bimetallic or trimetallic nanoparticles are considered more effective than monometallic nanoparticles because of their synergistic characteristics. In this review, we outline the structure, synthesis method, properties, and biological applications of metallic alloy nanoparticles based on their plasmonic, catalytic, and magnetic characteristics.


Assuntos
Ligas/química , Ligas/síntese química , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Ligas/uso terapêutico , Catálise , Diagnóstico por Imagem/métodos , Campos Magnéticos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Nanopartículas/uso terapêutico
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