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1.
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
2.
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
3.
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
4.
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
5.
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
6.
Nanotechnology ; 32(33)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-33979787

RESUMO

Measuring solution concentration plays an important role in chemical, biochemical, clinical diagnosis, environmental monitoring, and biological analyses. In this work, we develop a transmission-mode localized surface plasmon resonance sensor chip system and convenient method which is highly efficient, highly sensitive for detection sensing using multimode fiber. The plasmonically active sensor's surface AuNPs with high-density NPs were decorated onto 1 cm sensing length of various clad-free fiber in the form of homogeneous monolayer utilizing a self-assembly process for immobilization of the target molecule. The carboxyl bond is formed through a functional reaction on the sensor head. Using the significance in the refractive index difference and numerical aperture, which is caused by a variation in the concentration of measuring bovine serum albumin (BSA) protein which can be accurately measured by the output signal. The refractive index variation of the medium analyte layer can be converted to signal output power change at the He-Ne wavelength of 632.8 nm. The sensor detection limit was estimated to be 0.075 ng ml-1for BSA protein which shows high sensitivity compared to other types of label-free optical biosensors. This also leads to a possibility of finding the improvement in the sensitivity label-free biosensors. The conventional method should allow multimode fiber biosensors to become a possible replacement for conventional biosensing techniques based on fluorescence.

7.
BMC Infect Dis ; 21(1): 1130, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34727869

RESUMO

BACKGROUND: To investigate the knowledge, attitudes, and practices of the healthcare professionals (HCPs) including physicians and nurses regarding dengue transmission, diagnosis and clinical classification using the warning signs of World Health Organization (WHO) 2009 classification. RESULTS: Out of 471 respondents from three countries, 80.9% of physicians and 74% of nurses did not receive previous training regarding the dengue infection. The majority of respondents could identify the primary dengue vector (86%), while only a third of HCPs knew the biting time of dengue mosquitoes. Only half of our respondents knew about immunity induced by serotypes; Moreover, half of our participants could determine the diagnostic tests. On the other hand, about 90% of the respondents took responsibility for talking to the patients about preventive measures. Our respondents also showed wide variations in definition of warning signs listed in the WHO 2009 classification. Multivariate analysis linked the impact of different cofactors including prior training on dengue infection, type of profession, frequency of taking care of dengue patients and country on how HCPs defined these warning signs. CONCLUSIONS: This study could declare the variation in employing the warning signs listed in the WHO 2009 classification. We have figured that most of the HCPs did not take prior training on the dengue viral infection; Also, we found gaps in the knowledge regarding various topics in dengue fever. This paper recommends the gathering of efforts to establish the proper knowledge of dengue infection and the warning signs listed by the WHO.


Assuntos
Dengue , Conhecimentos, Atitudes e Prática em Saúde , Animais , Dengue/diagnóstico , Pessoal de Saúde , Humanos , Mosquitos Vetores , Inquéritos e Questionários
8.
Nanotechnology ; 31(33): 335712, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32357358

RESUMO

We integrate superparamagnetic iron oxide nanoparticles with polyaspartamide (PA) biopolymer to form a biological construct that functions as a tracking, targeting and drug-delivery system for cancer diagnosis and therapy. Iron oxide nanoparticles with uniformly distributed average spherical diameters of around 10 nm and superparamagnetic characteristics play a key role in increasing the transverse 1/T 2 relaxation rate or darkening the T 2-weighted MR image for cancer diagnosis using MRI. In in vitro MRI testing on cancer cells, the MR images of samples with the bio-constructshow a much clearer contrast effect than those of controls. The PA biopolymer plays an essential role in enhancing the hydrophilicity and biocompatibility of the bio-construct. In addition, as a multifunctional polymer, PA is conjugated with biotin and doxorubicin (Dox) functional groups to enhance targeting and impairment of cancer cells. In in vivo testing on cancer tumors, injection with the bio-construct decreased the magnitude of cancer tumor volume growth by three times compared with that of uninjected controls. The physicochemical characteristics of the bio-construct and the roles of biotin and Dox functional groups are examined and discussed in detail.


Assuntos
Antineoplásicos/administração & dosagem , Biopolímeros/administração & dosagem , Biotina/química , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Meios de Contraste/administração & dosagem , Células 3T3 , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Biopolímeros/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Meios de Contraste/química , Doxorrubicina , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas Magnéticas de Óxido de Ferro , Imageamento por Ressonância Magnética , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Mar Drugs ; 18(9)2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32937930

RESUMO

A new compound containing a triene, a tetrahydropyran ring and glycine ester functionalities, restricticin B (1), together with four known compounds (2-5) were obtained from the EtOAc extract of the marine-derived fungus Penicillium janthinellum. The planar structure of 1 was determined by detailed analyses of MS, 1D and 2D NMR data. The relative and absolute configurations of 1 were established via the analyses of NOESY spectroscopy data, the comparison of optical rotation values with those of reported restricticin derivatives and electronic circular dichroism (ECD). All the compounds were screened for their anti-neuroinflammatory effects in lipopolysaccharide (LPS)-induced BV-2 microglia cells. Restricticin B (1) and N-acetyl restricticin (2) exhibited anti-neuroinflammatory effects by suppressing the production of pro-inflammatory mediators in activated microglial cells.


Assuntos
Anti-Inflamatórios/farmacologia , Microglia/efeitos dos fármacos , Óxido Nítrico/metabolismo , Penicillium/metabolismo , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Sedimentos Geológicos/microbiologia , Microglia/metabolismo , Estrutura Molecular , Óxido Nítrico Sintase Tipo II/metabolismo , Relação Estrutura-Atividade
10.
Mar Drugs ; 18(6)2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32498331

RESUMO

Fucoidans from brown macroalgae (brown seaweeds) have different structures and many interesting bioactivities. Fucoidans are classically extracted from brown seaweeds by hot acidic extraction. Here, we report a new targeted enzyme-assisted methodology for fucoidan extraction from brown seaweeds. This enzyme-assisted extraction protocol involves a one-step combined use of a commercial cellulase preparation (Cellic®CTec2) and an alginate lyase from Sphingomonas sp. (SALy), reaction at pH 6.0, 40 °C, removal of non-fucoidan polysaccharides by Ca2+ precipitation, and ethanol-precipitation of crude fucoidan. The workability of this method is demonstrated for fucoidan extraction from Fucus distichus subsp. evanescens (basionym Fucus evanescens) and Saccharina latissima as compared with mild acidic extraction. The crude fucoidans resulting directly from the enzyme-assisted method contained considerable amounts of low molecular weight alginate, but this residual alginate was effectively removed by an additional ion-exchange chromatographic step to yield pure fucoidans (as confirmed by 1H NMR). The fucoidan yields that were obtained by the enzymatic method were comparable to the chemically extracted yields for both F. evanescens and S. latissima, but the molecular sizes of the fucoidans were significantly larger with enzyme-assisted extraction. The molecular weight distribution of the fucoidan fractions was 400 to 800 kDa for F. evanescens and 300 to 800 kDa for S. latissima, whereas the molecular weights of the corresponding chemically extracted fucoidans from these seaweeds were 10-100 kDa and 50-100 kDa, respectively. Enzyme-assisted extraction represents a new gentle strategy for fucoidan extraction and it provides new opportunities for obtaining high yields of native fucoidan structures from brown macroalgae.


Assuntos
Celulase , Fucus/química , Polissacarídeo-Liases , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Alga Marinha/química , Phaeophyceae
11.
Mar Drugs ; 17(6)2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31212583

RESUMO

Five new sesterterpenes, 14,15-dehydro-6-epi-ophiobolin K (1), 14,15-dehydro- ophiobolin K (2), 14,15-dehydro-6-epi-ophiobolin G (3), 14,15-dehydro-ophiobolin G (4) and 14,15-dehydro-(Z)-14-ophiobolin G (5), together with four known ophiobolins (6-9) were isolated from the marine fungus Aspergillus flocculosus derived from the seaweed Padina sp. collected in Vietnam. The five new ophiobolins were first isolated as ophiobolin derivatives consisting of a fully unsaturated side chain. Their structures were elucidated via spectroscopic methods including 1D, 2D NMR and HR-ESIMS. The absolute configurations were determined by the comparison of chemical shifts and optical rotation values with those of known ophiobolins. All compounds (1-9) were then evaluated for their cytotoxicity against six cancer cell lines, HCT-15, NUGC-3, NCI-H23, ACHN, PC-3 and MDA-MB-231. All the compounds showed potent cytotoxicity with GI50 values ranging from 0.14 to 2.01 µM.


Assuntos
Organismos Aquáticos/química , Aspergillus/química , Fungos/química , Sesterterpenos/química , Sesterterpenos/farmacologia , Linhagem Celular Tumoral , Humanos , Células PC-3 , Alga Marinha/microbiologia , Vietnã
12.
Mar Drugs ; 17(10)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614563

RESUMO

Four new compounds were isolated from the Vietnamese marine sediment-derived fungus Aspergillus flocculosus, one aspyrone-related polyketide aspilactonol G (2), one meroterpenoid 12-epi-aspertetranone D (4), two drimane derivatives (7,9), together with five known metabolites (1,3,5,6,8,10). The structures of compounds 1-10 were established by NMR and MS techniques. The absolute stereoconfigurations of compounds 1 and 2 were determined by a modified Mosher's method. The absolute configurations of compounds 4 and 7 were established by a combination of analysis of ROESY data and coupling constants as well as biogenetic considerations. Compounds 7 and 8 exhibited cytotoxic activity toward human prostate cancer 22Rv1, human breast cancer MCF-7, and murine neuroblastoma Neuro-2a cells.


Assuntos
Antineoplásicos/farmacologia , Organismos Aquáticos/metabolismo , Aspergillus/metabolismo , Produtos Biológicos/farmacologia , Fungos/metabolismo , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Sedimentos Geológicos/microbiologia , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética/métodos , Biologia Marinha/métodos , Camundongos , Sesquiterpenos Policíclicos/farmacologia , Policetídeos/farmacologia , Sesquiterpenos/farmacologia
13.
Molecules ; 25(1)2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878044

RESUMO

Seven known echinulin-related indolediketopiperazine alkaloids (1-7) were isolated from the Vietnamese sediment-derived fungus Aspergillus niveoglaucus. Using chiral HPLC, the enantiomers of cryptoechinuline B (1) were isolated as individual compounds for the first time. (+)-Cryptoechinuline B (1a) exhibited neuroprotective activity in 6-OHDA-, paraquat-, and rotenone-induced in vitro models of Parkinson's disease. (-)-Cryptoechinuline B (1b) and neoechinulin C (5) protected the neuronal cells against paraquat-induced damage in a Parkinson's disease model. Neoechinulin B (4) exhibited cytoprotective activity in a rotenone-induced model, and neoechinulin (7) showed activity in the 6-OHDA-induced model.


Assuntos
Alcaloides/farmacologia , Aspergillus/química , Fármacos Neuroprotetores/farmacologia , Piperazina/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Humanos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Paraquat/toxicidade , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/tratamento farmacológico , Piperazina/análogos & derivados , Piperazina/química , Piperazina/isolamento & purificação
14.
Environ Manage ; 63(4): 444-454, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29453646

RESUMO

Radioactivity concentrations of nuclides of the 232Th and 238U radioactive chains and 40K, 90Sr, 137Cs, and 239+240Pu were surveyed for raw and cooked food of the population in the Red River delta region, Vietnam, using α-, γ-spectrometry, and liquid scintillation counting techniques. The concentration of 40K in the cooked food was the highest compared to those of other radionuclides ranging from (23 ± 5) (rice) to (347 ± 50) Bq kg-1 dw (tofu). The 210Po concentration in the cooked food ranged from its limit of detection (LOD) of 5 mBq kg-1 dw (rice) to (4.0 ± 1.6) Bq kg-1 dw (marine bivalves). The concentrations of other nuclides of the 232Th and 238U chains in the food were low, ranging from LOD of 0.02 Bq kg-1 dw to (1.1 ± 0.3) Bq kg-1 dw. The activity concentrations of 90Sr, 137Cs, and 239+240Pu in the food were minor compared to that of the natural radionuclides. The average annual committed effective dose to adults in the study region was estimated and it ranged from 0.24 to 0.42 mSv a-1 with an average of 0.32 mSv a-1, out of which rice, leafy vegetable, and tofu contributed up to 16.2%, 24.4%, and 21.3%, respectively. The committed effective doses to adults due to ingestion of regular diet in the Red River delta region, Vietnam are within the range determined in other countries worldwide. This finding suggests that Vietnamese food is safe for human consumption with respect to radiation exposure.


Assuntos
Contaminação Radioativa de Alimentos , Adulto , Ingestão de Alimentos , Humanos , Rios , Vietnã
15.
J Nanosci Nanotechnol ; 18(5): 3624-3630, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442876

RESUMO

In order to improve dispersiveness of nanosilica in polymer matrix, surface organo-modification of nanosilica is necessary. This work reveals silica nanoparticles modified by titanate coupling agent isopropyltri (dioctylphosphate) titanate (KR12) in toluene solvent. Effect of reaction temperature, reaction time and reactant ratio on grafting efficiency have been studied by Thermogravimetric Analysis (TGA). The obtained results exhibit the grafted percentage of titanate coupling agent KR-12 on the surface of nanosilica increased quickly from 4.97 to 13.11 wt.% as increasing the content of KR-12 from 5 to 15 wt.% and raise slower from 13.21 to 13.43 wt.% as content of KR-12 in the range of 30 to 45 wt.%, respectively. The KR-12 content and grafting reaction time affect significantly on the grafting efficiency while temperature of grafting reaction is negative to the grafting efficiency. The results of analysis related to Infrared Spectroscopy and Energy-Dispersive X-ray spectroscopy (EDS) displayed titanate coupling agent KR-12 have been covalently bonded to surface of the nanosilica. The Transmission Electron Microscopy (TEM) images and size distribution indicated that after organic modification, nanosilica particles had average size about 86 nm and the agglomeration of nanoparticles decreased significantly. The obtained results showed that surface treatment of nanosilica with titanate coupling agent KR-12 was successful.

16.
Mar Drugs ; 16(1)2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29304006

RESUMO

A new α-pyrone merosesquiterpenoid possessing an angular tetracyclic carbon skeleton, ochraceopone F (1), and four known secondary metabolites, aspertetranone D (2), cycloechinulin (3), wasabidienone E (4), and mactanamide (5), were isolated from the marine fungus Aspergillus flocculosus derived from a sponge Stylissa sp. collected in Vietnam. The structures of Compounds 1-5 were elucidated by analysis of 1D and 2D NMR spectra and MS data. All the isolated compounds were evaluated for anti-proliferation activity and their suppression effects on receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclast differentiation using tartate-resisant acid phosphatase (TRAP). Compounds 1-5 had no anti-proliferative effect on human cancer cell lines up to 30 µg/mL. Among these compounds, aspertetranone D (2) and wasabidienone E (4) exhibited weak osteoclast differentiation inhibitory activity at 10 µg/mL. However, mactanamide (5) showed a potent suppression effect of osteoclast differentiation without any evidence of cytotoxicity.


Assuntos
Aspergillus/metabolismo , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Poríferos/microbiologia , Animais , Aspergillus/isolamento & purificação , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Osteoclastos/metabolismo , Ligante RANK/metabolismo , Metabolismo Secundário , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Vietnã
17.
Clin Infect Dis ; 64(12): 1784-1787, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28158507

RESUMO

We utilized polymerase chain reaction (PCR) to demonstrate that Angiostrongylus cantonensis was responsible for 67.3% of 55 cases of eosinophilic meningitis from a cohort of 1,690 adult patients with CNS infection at a tertiary hospital in southern Vietnam. Longer duration of illness, depressed consciousness, and peripheral blood eosinophilia were associated with PCR positivity.


Assuntos
Angiostrongylus cantonensis/isolamento & purificação , Eosinofilia/parasitologia , Meningite/parasitologia , Infecções por Strongylida/parasitologia , Adolescente , Adulto , Angiostrongylus cantonensis/genética , Animais , Estudos de Coortes , Eosinofilia/epidemiologia , Feminino , Humanos , Masculino , Meningite/epidemiologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , Infecções por Strongylida/diagnóstico , Infecções por Strongylida/epidemiologia , Centros de Atenção Terciária , Vietnã/epidemiologia , Adulto Jovem
18.
Virol J ; 12: 85, 2015 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-26050791

RESUMO

BACKGROUND: Hand foot and mouth disease (HFMD) is a disease of public health importance across the Asia-Pacific region. The disease is caused by enteroviruses (EVs), in particular enterovirus A71 (EV-A71). In EV-A71-associated HFMD, the infection is sometimes associated with severe manifestations including neurological involvement and fatal outcome. The availability of a robust diagnostic assay to distinguish EV-A71 from other EVs is important for patient management and outbreak response. METHODS: We developed and validated an internally controlled one-step single-tube real-time RT-PCR in terms of sensitivity, linearity, precision, and specificity for simultaneous detection of EVs and EV-A71. Subsequently, the assay was then applied on throat and rectal swabs sampled from 434 HFMD patients. RESULTS: The assay was evaluated using both plasmid DNA and viral RNA and has shown to be reproducible with a maximum assay variation of 4.41 % and sensitive with a limit of detection less than 10 copies of target template per reaction, while cross-reactivity with other EV serotypes was not observed. When compared against a published VP1 nested RT-PCR using 112 diagnostic throat and rectal swabs from 112 children with a clinical diagnosis of HFMD during 2014, the multiplex assay had a higher sensitivity and 100 % concordance with sequencing results which showed EVs in 77/112 (68.8 %) and EV-A71 in 7/112 (6.3 %). When applied to clinical diagnostics for 322 children, the assay detected EVs in throat swabs of 257/322 (79.8 %) of which EV-A71 was detected in 36/322 (11.2 %) children. The detection rate increased to 93.5 % (301/322) and 13.4 % (43/322) for EVs and EV-A71, respectively, when rectal swabs from 65 throat-negative children were further analyzed. CONCLUSION: We have successfully developed and validated a sensitive internally controlled multiplex assay for rapid detection of EVs and EV-A71, which is useful for clinical management and outbreak control of HFMD.


Assuntos
Infecções por Enterovirus/diagnóstico , Enterovirus/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Animais , Ásia , Criança , Pré-Escolar , Enterovirus/classificação , Enterovirus/genética , Feminino , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase Multiplex/normas , Faringe/virologia , Reação em Cadeia da Polimerase em Tempo Real/normas , Reto/virologia , Padrões de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Sensibilidade e Especificidade
19.
Int J Biol Macromol ; 263(Pt 2): 130299, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387633

RESUMO

In this study, development of bioactive coatings containing 1 % (w/v) chitosan (CS), 0.6 % (w/v) diepoxy-polyethylene glycol (PEG), and trans-cinnamaldehyde (CIN) was achieved. The physicochemical and biological properties of the coatings were investigated. The tensile strength, light transmission, water vapor permeability (WVP), and antibacterial properties were enhanced by the incorporation of CIN. The CIN-containing films appeared compact and rough, as observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). In addition, the quality attributes of the bananas were evaluated at room temperature for 24 days, and the results showed that the CS/PEG/CIN coating delayed the respiration peak, weight loss, sugar content loss, and maintained firmness, color, total soluble solids (TSS), titratable acid (TA), and the appearance of the bananas. Principal component analysis (PCA) revealed that the bioactive coating significantly affected the respiration rate and weight loss of bananas.


Assuntos
Acroleína/análogos & derivados , Quitosana , Musa , Óleos Voláteis , Quitosana/química , Polietilenoglicóis/química , Óleos Voláteis/farmacologia , Redução de Peso
20.
Int J Biol Macromol ; 262(Pt 1): 130014, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340933

RESUMO

The incorporation of ginger oil (GO) influenced the physical, optical, and structural properties of the chitosan (CH) film including the decreases of moisture content (60.15 %), water solubility (35.37 %) and water vapor permeability (WVP) (32.79 %) and the increases of tensile strength (TS) (125 %), elongation at break (EAB) (2.74 %) and opacity (131.08 %). Antifungal capacity of the CH film was enhanced when GO was added to the film. The CH + GO film showed a less homogeneous surface that the presence of the oil droplets on the film surface. Moreover, the CH and CH + GO coatings reduced weight loss of persimmon by 14.87 %, and 21.13 %, respectively, compared to the control. Moisture content loss of the coated CH- and the coated CH + GO- persimmons was decreased by 1.94 % and 4.92 %, respectively, compared to that of the control persimmon. Furthermore, the CH and CH + GO coatings decreased in color changes, respiration rate, ethylene production, changes in pH and TSS, and remained firmness of persimmon during storage at 25 °C. In addition, X-ray CT images can be used to monitor internal changes and observe the tissue breakdown during storage period. The ΔGS value can be used as a predictor of persimmon internal qualities. Thus, the CH film containing GO can be applied as an active packaging material.


Assuntos
Quitosana , Diospyros , Filmes Comestíveis , Óleos Voláteis , Zingiber officinale , Quitosana/química , Tomografia Computadorizada por Raios X , Permeabilidade , Embalagem de Alimentos
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