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1.
Biomacromolecules ; 25(9): 5995-6006, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39133657

RESUMEN

Sacran is a cyanobacterial supergiant polysaccharide with carboxylate and sulfate groups that exhibits antiallergic and antiinflammatory properties. However, its high anionic functions restrict cell compatibility. Quaternary ammonium groups were substituted to form sacran ampholytes, and the cell compatibility of the cationized sacran hydrogels was evaluated. The cationization process involved the reaction of N-(3-chloro-2-hydroxypropyl)trimethylammonium chloride with the primary amine or hydroxyl groups of sacran. The degree of cationization ranged from 32 to 87% for sugar residues. Hydrogels of sacran ampholytes were prepared by annealing their dried sheets by thermal cross-linking; these hydrogels exhibited anisotropic expansion properties. The water contact angle on the hydrogels decreased from 26.5 to 15.3° with an increase in the degree of cationization, thereby enhancing hydrophilicity. The IC50 values of sacran ampholytes decreased with an increased degree of cationization, resulting in a reduction in cytotoxicity toward the L-929 mouse fibroblast cell line. This reduction was associated with an increase in the cell proliferation density after 3 days of incubation. Scanning electron microscopy images showed fibroblast intercellular connections. Therefore, the sacran ampholyte hydrogel exhibited increased hydrophilicity and cell compatibility, which is beneficial for various biomedical applications.


Asunto(s)
Cianobacterias , Hidrogeles , Polisacáridos , Hidrogeles/química , Hidrogeles/farmacología , Ratones , Animales , Polisacáridos/química , Polisacáridos/farmacología , Cianobacterias/química , Fibroblastos/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Cationes/química , Compuestos de Amonio Cuaternario/química , Compuestos de Amonio Cuaternario/farmacología , Sulfatos/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Propanoles
2.
ScientificWorldJournal ; 2022: 7120662, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35991089

RESUMEN

A clearer understanding of research streams and players involved in efforts to address the sustainability of global food and agricultural systems is needed to clarify the current state of scientific knowledge and form collaborations to pursue future research directions. This study presents new insights into this issue through a scientometric process involving a case study of technologies for extending fruit shelf-life. The text mining software was utilized to analyze 3,131 Web of Science-indexed articles published between 2000 and 2020 as a means to glean the conceptual structure of current knowledge and conduct a social network analysis to explore scientific and publication activity. The findings were mapped onto a strategic diagram of research productivity and collaboration between players at the national, organizational, and individual levels. This research's main findings highlight that research on shelf-life technology is in continuous development, and academic institutions from China, Spain, and the U.S. are the core national players in this field. The results provide insights for further investigation to strengthen co-research and technological development programs in other fields. Researchers who are exploring networking opportunities can use the model and process presented as a guideline for identifying emerging and future research trends and formulating strategies.


Asunto(s)
Bibliometría , Tecnología , China , Conocimiento , Esperanza de Vida
3.
Pharmacol Rev ; 70(3): 412-445, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29669750

RESUMEN

Glioblastoma multiforme (GBM), the most common and aggressive primary brain tumor, has a high mortality rate despite extensive efforts to develop new treatments. GBM exhibits both intra- and intertumor heterogeneity, lending to resistance and eventual tumor recurrence. Large-scale genomic and proteomic analysis of GBM tumors has uncovered potential drug targets. Effective and "druggable" targets must be validated to embark on a robust medicinal chemistry campaign culminating in the discovery of clinical candidates. Here, we review recent developments in GBM drug discovery and delivery. To identify GBM drug targets, we performed extensive bioinformatics analysis using data from The Cancer Genome Atlas project. We discovered 20 genes, BOC, CLEC4GP1, ELOVL6, EREG, ESR2, FDCSP, FURIN, FUT8-AS1, GZMB, IRX3, LITAF, NDEL1, NKX3-1, PODNL1, PTPRN, QSOX1, SEMA4F, TH, VEGFC, and C20orf166AS1 that are overexpressed in a subpopulation of GBM patients and correlate with poor survival outcomes. Importantly, nine of these genes exhibit higher expression in GBM versus low-grade glioma and may be involved in disease progression. In this review, we discuss these proteins in the context of GBM disease progression. We also conducted computational multi-parameter optimization to assess the blood-brain barrier (BBB) permeability of small molecules in clinical trials for GBM treatment. Drug delivery in the context of GBM is particularly challenging because the BBB hinders small molecule transport. Therefore, we discuss novel drug delivery methods, including nanoparticles and prodrugs. Given the aggressive nature of GBM and the complexity of targeting the central nervous system, effective treatment options are a major unmet medical need. Identification and validation of biomarkers and drug targets associated with GBM disease progression present an exciting opportunity to improve treatment of this devastating disease.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Animales , Antineoplásicos/administración & dosificación , Barrera Hematoencefálica/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Sistemas de Liberación de Medicamentos , Descubrimiento de Drogas , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Proteómica
4.
AAPS PharmSciTech ; 18(4): 1104-1115, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27796908

RESUMEN

Lung cancer is one of the most of cancer type founds and a leading cause of death worldwide. Through the development of new candidate compound (3,4,5-tribenzyloxybenzoic acid (GAOBn)) and a drug delivery system of our design of quaternized chitosan-gallic acid-folic acid stabilized gold nanoparticles (Au@QCS-GA-FA) as the targeted nanocarrier for treatment of lung cancer, we have found that GAOBn not only showed high cytotoxicity against lung cancer cells (CHAGO) with more than tenfold than cisplatin, but also showed low toxicity against normal cells (CRL-1947). The combination Au@QCS-GA-FA/GAOBn showed highly efficient cellular uptake and localization of gold nanoparticles via the active targeting of cancer cells. This established the potential of Au@QCS-GA-FA as a nanocarrier for anticancer agent-targeted delivery for treatment of lung cancer.


Asunto(s)
Quitosano , Cisplatino , Ácido Fólico/farmacología , Ácido Gálico/farmacología , Oro , Neoplasias Pulmonares/tratamiento farmacológico , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Quitosano/química , Quitosano/farmacología , Cisplatino/administración & dosificación , Cisplatino/farmacocinética , Sistemas de Liberación de Medicamentos , Excipientes/farmacología , Oro/química , Oro/farmacología , Humanos , Nanopartículas del Metal
5.
J Microencapsul ; 32(5): 450-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26052720

RESUMEN

The purpose of this study was to design and characterise an oral mucoadhesive micellar drug carrier. In this regard, a mucoadhesive hydrophobic cationic aminocellulose was easily synthesised under mild homogeneous conditions with high yield. The cellulose derivative resulted in strongly improved mucoadhesive properties but was pH dependent. Furthermore, the hydrophobic anticancer drug camptothecin was successfully encapsulated into the mucoadhesive cellulose derivative micelles with spherical shape stability of 233 nm in diameter and low particle size distribution. The CPT-loaded nanocarriers provided high encapsulation efficiency about 86.4%. In vitro release, CPT-loaded cellulose derivative micelles showed a reduction in release rate compared with physically pure CPT solution. The release results also indicated that a sustained release of CPT to >80% over 4 d for pH 6.8 and 7.4. Therefore, mucoadhesive hydrophobic cationic aminocellulose micelles seem to be a promising carrier for various pharmaceutical applications especially for poorly water-soluble drug delivery system.


Asunto(s)
Camptotecina/química , Celulosa/química , Micelas , Nanocápsulas/química , Animales , Solubilidad , Porcinos
6.
Bioorg Med Chem Lett ; 24(13): 2845-50, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24835201

RESUMEN

Four series of cassiarin A derivatives with alkanoyl (3a-3d), aroyl (4a-4d), hydroxy/amino-substituted ethylene glycol (5a-5c) and selenium-containing (6a) side chains were synthesized. Their antitumor activities were evaluated against BT474, CHAGO, HepG2, KATO-III, SW620 and CaSki cancer cell lines. Preliminary results demonstrated that 5b had moderate activities against HepG2 and KATO-III cell lines, while 5c showed moderate to high cytotoxicity against most tested cell lines. In addition, 6a exhibited moderate cytotoxicity against cervical cells, CaSki. DNA-binding and ethidium bromide displacement experiments suggested that 5c and 5b binds to DNA via an intercalative mode, whereas 6a did not. However, the selenium-containing cassiarin A derivative 6a inhibited topoisomerase II with more than 95% inhibition at the concentration of 50 µM. These cassiarin A derivatives showed lower toxicity to normal cells, WI-38 than amonafide therefore they are potential lead compounds to be further developed as new anticancer agents.


Asunto(s)
Antineoplásicos/farmacología , ADN-Topoisomerasas de Tipo II/metabolismo , ADN/efectos de los fármacos , Compuestos Heterocíclicos con 3 Anillos/farmacología , Inhibidores de Topoisomerasa II/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Sitios de Unión/efectos de los fármacos , Bovinos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , ADN/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células Hep G2 , Compuestos Heterocíclicos con 3 Anillos/síntesis química , Compuestos Heterocíclicos con 3 Anillos/química , Humanos , Estructura Molecular , Relación Estructura-Actividad , Inhibidores de Topoisomerasa II/síntesis química , Inhibidores de Topoisomerasa II/química
7.
Anim Biosci ; 37(8): 1440-1451, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38575120

RESUMEN

OBJECTIVE: This study aimed to develop and evaluate the effectiveness of a water-soluble microencapsulation method for probiotic strains using gum Arabic (GA) and skim milk (SKM) over a three-month storage period following processing. METHODS: Four strains of Pediococcus acidilactici (BYF26, BYF20, BF9, and BF14) that were typical lactic acid bacteria (LAB) isolated from the chicken gut were mixed with different ratios of GA and SKM as coating agents before spray drying at an inlet temperature 140°C. After processing, the survivability and probiotic qualities of the strains were assessed from two weeks to three months of storage at varied temperatures, and de-encapsulation was performed to confirm the soluble properties. Finally, the antibacterial activity of the probiotics was assessed under simulated gastrointestinal conditions. RESULTS: As shown by scanning electron microscopy, spray-drying produced a spherical, white-yellow powder. The encapsulation efficacy (percent) was greatest for a coating containing a combination of 30% gum Arabic: 30% skim milk (w/v) (GA:SKM30) compared to lower concentrations of the two ingredients (p<0.05). Coating with GA:SKM30 (w/v) significantly enhanced (p<0.05) BYF26 survival under simulated gastrointestinal conditions (pH 2.5 to 3) and maintained higher survival rates compared to non-encapsulated cells under an artificial intestinal juices condition of pH 6. De-encapsulation tests indicated that the encapsulated powder dissolved in water while keeping viable cell counts within the effective range of 106 for 6 hours. In addition, following three months storage at 4°C, microencapsulation of BYF26 in GA:SKM30 maintained both the number of viable cells (p<0.05) and the preparation's antibacterial efficacy against pathogenic bacteria, specifically strains of Salmonella. CONCLUSION: Our prototype water-soluble probiotic microencapsulation GA:SKM30 effectively maintains LAB characteristics and survival rates, demonstrating its potential for use in preserving probiotic strains that can be used in chickens and potentially in other livestock.

8.
Bioorg Med Chem Lett ; 23(22): 6156-60, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24095089

RESUMEN

Overcoming drug resistance with remarkable cytotoxic activity by anthracene-9,10-dione derivatives would offer a potential therapeutic strategy. In this study, we report the synthesis and the cytotoxicity of a novel set of anthraquninones. (4-(4-Aminobenzylamino)-9,10-dioxo-9,10-dihydroanthracen-1-yl-4-methylbenzenesulfonate) (3) has excellent in vitro cytotoxicity against doxorubicin-resistant cancer cell line (IC50=0.8 µM), 20-fold higher than doxorubicin. The cytotoxic effect via G2/M arrest does not appear to be ROS.


Asunto(s)
Antraquinonas/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Doxorrubicina/farmacología , Antraquinonas/química , Antibióticos Antineoplásicos/farmacología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos
9.
Sci Rep ; 13(1): 1844, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36725957

RESUMEN

Herein, a sensitive colorimetric detection strategy is proposed for Ag+ detection based on the use of environmentally friendly synthesis of gold nanoparticles (AuNPs), at room temperature, using (tannic acid, TA), as the reductant and pullulan (PUL) as stabilizing agent. The colloidal solution (TA/PUL-AuNPs), at the optimal synthesis conditions, showed maximum absorbance at 529 nm with a berry red color. TEM and FESEM validated that the particles are spherical and monodispersed, while other characterization results elucidated the role of pullulan in the nano-synthesis. Ag+ addition to the probe (TA/PUL-AuNPs), pH 11, resulted in naked-eye color changes, owing to Au@Ag core shell nanostructure formation. Further, the added Ag+ is reduced to AgNPs, on the surface of the TA/PUL-AuNPs probe. A hypsochromic shift in the absorption maximum, from 529 to 409 nm was observed, while (AAg+-Abl)@409 nm exhibited linearity with Ag+ concentrations, from 0.100 to 150 µM. The estimated limit of detection was 30.8 nM, which is far lower than the acceptable limit of 0.930 µM from the regulatory agency. The TA/PUL-AuNPs probe was further tested for Ag+ detection in lake water samples, and it displayed satisfactory detection performances for real sample applications.

10.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 8): o2550-1, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22904982

RESUMEN

THE TITLE COMPOUND (SYSTEMATIC NAME: methyl 2-{(1R,2R)-2-[(1aS,4S,4aS,8aS)-4-(furan-3-yl)-4a-methyl-8-methyl-ene-2-oxoocta-hydro-oxireno[2,3-d]isochromen-7-yl]-2,6,6-trimethyl-5-oxocyclo-hex-3-en-1-yl}acetate), C(27)H(32)O(7), was isolated from X. moluccensis seeds from Thailand. The conformations of the six-membered rings are distorted half-chair, chair and half-chair for the isolated cyclo-hexane, fused cyclo-hexane and lactone rings, respectively. In addition, the lactone ring bears in an equatorial orientation an essentially planar furan ring (r.m.s. deviation = 0.004 Å), which forms an angle of 63.87 (13)° with the mean plane defined by the ten atoms of the two fused six-membered rings (r.m.s. deviation = 0.213 Å). The absolute configuration was fixed on the basis of literature data.

11.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): m775, 2012 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-22719328

RESUMEN

In the title compound, [Cu(C(2)H(3)O(2))(2)(C(12)H(12)N(2))(2)]·H(2)O, the Cu(II) atom exhibits a distorted octa-hedral coordination geometry, defined by two N atoms from one 4,4'-dimethyl-2,2'-bipyridine ligand and four O atoms from two acetate ligands. In the crystal, O-H⋯O hydrogen bonds are observed between the coordinated carboxyl-ate O atoms and the solvent water mol-ecule.

12.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): o1423-4, 2012 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-22590307

RESUMEN

The title mol-ecule, C(28)H(20)O(8)S(2), has a T-shaped conformation. The central 9,10-anthraquinone moiety is bow-shaped with the two outer aromatic rings being inclined to one another by 13.99 (11)°. The benzenesulfonate rings are inclined to one another by 47.35 (12)°, and by 34.51 (11) and 17.88 (11)° to the bridging aromatic ring of the 9,10-anthraquinone moiety. In the crystal, C-H⋯O interactions link the mol-ecules into ribbons in [100].

13.
Carbohydr Polym ; 277: 118858, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34893265

RESUMEN

We report herein the development of the novel nanohybrids of gold nanoparticles reduced/stabilized/coated with collagen (AuNPs@collagen) in the first layer and subsequently modified with biotin-quat188-chitosan (Bi-QCS) in the outer layer for 5-fluorouracil (5-FU) delivery to improve cellular uptake and promote specific cell targeting of the nanocarrier. The fabrication of the layer-by-layer technique on the surface of gold nanoparticles (AuNPs) can overcome the limitation of poor drug loading capacity of the classic AuNPs from 64.67% to 87.46%. The AuNPs@collagen coated by the Bi-QCS exhibits strong electrostatic interactions between drug anion (5-FU) and amine groups of the modified chitosan as well as hydrogen bonding. Furthermore, the Bi-QCS-AuNPs@collagen demonstrated a significantly higher anti-inflammatory activity in RAW264.7 macrophage cell line. The Bi-QCS-AuNPs@collagen enhanced the activity of 5-FU approximately 3.3-fold (HeLa) and 6.2-fold (A549), compared to the free 5-Fluorouracil. According to these results, it is very promising that Bi-QCS-AuNPs@collagen can be used as an effective drug delivery carrier in the future.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Antimetabolitos Antineoplásicos/farmacología , Sistemas de Liberación de Medicamentos , Fluorouracilo/farmacología , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Antimetabolitos Antineoplásicos/síntesis química , Antimetabolitos Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Quitosano/química , Colágeno/química , Liberación de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Fluorouracilo/síntesis química , Fluorouracilo/química , Oro/química , Humanos , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Nanopartículas del Metal/química , Ratones , Estructura Molecular , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Tamaño de la Partícula , Células RAW 264.7
14.
Sci Rep ; 12(1): 7210, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35505092

RESUMEN

Lactiplantibacillus plantarum (strains 22F and 25F) and Pediococcus acidilactici (strain 72N) have displayed antibacterial activity in vitro, suggesting that they could be used to support intestinal health in pigs. The aim of this study was to determine if microencapsulated probiotics could reduce the severity of infection with enterotoxigenic Escherichia coli (ETEC) in weaned pigs. Sixty healthy neonatal piglets were cross-fostered and separated into five groups. Piglets to be given the microencapsulated probiotics received these orally on days 0, 3, 6, 9, and 12. Only piglets in groups 1 and 5 did not receive probiotics: those in groups 2 and 4 received the three microencapsulated probiotic strains (multi-strain probiotic), and piglets in group 3 received microencapsulated P. acidilactici strain 72N. After weaning, the pigs in groups 3-5 were challenged with 5 mL (at 109 CFU/mL) of pathogenic ETEC strain L3.2 carrying the k88, staP, and stb virulence genes. The multi-strain probiotic enhanced the average daily gain (ADG) and feed conversion ratio (FCR) of weaned piglets after the ETEC challenge (group 4), whilst supplementing with the single-strain probiotic increased FCR (group 3). Piglets in groups 3 and 4 developed mild to moderate diarrhoea and fever. In the probiotic-fed piglets there was an increase in lactic acid bacteria count and a decrease in E. coli count in the faeces. By using real-time PCR, virulence genes were detected at lower levels in the faeces of pigs that had received the probiotic strains. Using the MILLIPLEX MAP assay, probiotic supplementation was shown to reduce pro-inflammatory cytokines (IL-1α, IL-6, IL-8, and TNFα), while group 4 had high levels of anti-inflammatory cytokine (IL-10). Challenged piglets receiving probiotics had milder intestinal lesions with better morphology, including greater villous heights and villous height per crypt depth ratios, than pigs just receiving ETEC. In conclusion, prophylactic administration of microencapsulated probiotic strains may improve outcomes in weaned pigs with colibacillosis.


Asunto(s)
Escherichia coli Enterotoxigénica , Pediococcus acidilactici , Probióticos , Enfermedades de los Porcinos , Animales , Diarrea/microbiología , Probióticos/farmacología , Probióticos/uso terapéutico , Porcinos , Enfermedades de los Porcinos/microbiología , Enfermedades de los Porcinos/prevención & control
15.
Bioorg Med Chem Lett ; 21(16): 4813-8, 2011 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21741833

RESUMEN

6-Deoxyclitoriacetal (1) and a series of 11 further derivatives of it (2-12) were synthesized and evaluated for their cytotoxic and topoisomerase IIα inhibitory activities. Compounds bearing epoxide (2), morpholine (6) and benzylamine (10) moieties showed promising in vitro cytotoxic activities against four cancer cell lines, with IC(50) values ranging from 0.38 to 0.73 µM. These three compounds also strongly inhibited topoisomerase II activity at 68.3-93.5% and showed a moderately high DNA intercalating property.


Asunto(s)
Antineoplásicos/farmacología , ADN-Topoisomerasas de Tipo II/metabolismo , Inhibidores Enzimáticos/farmacología , Rotenona/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Bovinos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Estructura Molecular , Rotenona/análogos & derivados , Rotenona/síntesis química , Estereoisomerismo , Relación Estructura-Actividad , Temperatura
16.
Bioorg Med Chem Lett ; 21(15): 4485-9, 2011 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-21733687

RESUMEN

A new andirobin, thaimoluccensin A (1), and two new phragmalin-type limonoids, thaimoluccensins B (2) and C (3), were isolated from seeds of a Thai mangrove plant, Xylocarpus moluccensis, together with eight known compounds. The structures of these compounds were elucidated on the basis of spectroscopic data. Only 7-deacetylgedunin (7), a gedunin-type limonoid, exhibited significant inhibitory activity against nitric oxide production from activated macrophages with IC(50) value less than 10 µM, suggesting that the compound has anti-inflammatory activity.


Asunto(s)
Antiinflamatorios/química , Cumarinas/química , Limoninas/química , Meliaceae/química , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Cumarinas/aislamiento & purificación , Cumarinas/farmacología , Humanos , Limoninas/aislamiento & purificación , Limoninas/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Espectroscopía de Resonancia Magnética , Conformación Molecular , Óxido Nítrico/metabolismo , Semillas/química , Tailandia
17.
Mar Drugs ; 9(9): 1649-1663, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22131963

RESUMEN

The controlled release of diclofenac sodium (DFNa) from a chitosan-oxidized konjac glucomannan (CTS-OKG) polymer film was studied. Konjac glucomannan (KGM) was initially oxidized by sodium periodate and then cross-linked to CTS via imine bonds (-C=N-) to form the new CTS-OKG copolymer. The DFNa loaded CTS-OKG polymers were characterized by Fourier transformed infrared spectroscopy (FT-IR) and X-ray diffractometry (XRD). Finally, the release profiles of DFNa from the CTS-OKG polymer matrices were evaluated in a simulated gastrointestinal fluid system comprised of two hours in simulated gastric fluid (SGF; pH 1.2) followed by 24 h in simulated intestinal fluid (SIF; pH 7.4). A 1:2:1 (w/w/w) ratio of CTS:OKG:DFNa prepared at room temperature for 3 hours gave the highest % encapsulation efficiency (EE) of 95.6 ± 0.6 and resulted in a minimal release of DFNa (<1% over 2 h) in SGF (pH 1.2) and a significantly improved sustained release in SIF (pH 7.4) with ~6% and 19% release over 8 and 24 h, respectively), some 15- and five-fold lower than that of the two commercial DFNa preparations, Diclosian and Voltaren. This formulation may be used for further study as a long term intestine controlled release drug model (at least 3 days).


Asunto(s)
Quitosano/administración & dosificación , Diclofenaco/administración & dosificación , Mananos/administración & dosificación , Preparaciones de Acción Retardada , Diclofenaco/química , Oxidación-Reducción , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
18.
AAPS PharmSciTech ; 12(1): 35-45, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21161458

RESUMEN

Sustained release mucoadhesive amoxicillin tablets with tolerance to acid degradation in the stomach were studied. The sustained-release tablets of amoxicillin were prepared from amoxicillin coated with ethyl cellulose (EC) and then formulated into tablets using chitosan (CS) or a mixture of CS and beta-cyclodextrin (CD) as the retard polymer. The effects of various (w/w) ratios of EC/amoxicillin, the particle sized of EC coated amoxicillin and the different (w/w) ratios of CS/CD for the retard polymer, on the amoxicillin release profile were investigated. The physicochemical properties of the EC coated amoxicillin particles and tablets were determined by scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry. The result showed that the release profiles of amoxicillin were greatly improved upon coating with EC, while the inclusion of CD to the CS retardant additionally prolonged the release of the drug slightly. Overall, a sustained release of amoxicillin was achieved using amoxicillin coated with EC at a (w/w) ratio of 1:1 and a particle size of 75-100 µm. Therefore, the tablet formulation of amoxicillin may be an advantageous alternative as an orally administered sustained-release formulation for the treatment of peptic ulcers.


Asunto(s)
Amoxicilina/administración & dosificación , Amoxicilina/química , Antibacterianos/administración & dosificación , Antibacterianos/química , Quitosano/química , Sistemas de Liberación de Medicamentos , beta-Ciclodextrinas/química , Rastreo Diferencial de Calorimetría , Celulosa/análogos & derivados , Celulosa/química , Preparaciones de Acción Retardada , Portadores de Fármacos , Composición de Medicamentos , Excipientes/química , Ácido Gástrico/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Comprimidos , Difracción de Rayos X
19.
IEEE Access ; 9: 45001-45016, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34812387

RESUMEN

As a global pandemic threatens health and livelihoods, finding effective treatments has become a vital issue that requires worldwide collaboration. This study examines research collaboration and network profiles through a case study of coronavirus diseases, including both the extinct severe acute respiratory syndrome coronavirus (SARS-CoV) and the emerging species (SARS-CoV-2). A scientometric process was designed to apply quantitative tools and a qualitative approach employing technological expertise to accomplish a three-level collaboration analysis. The text mining software, VantagePoint, was used to analyze research articles from the Web of Science database to identify the key national, organizational, and individual players in the coronavirus research field combined with indicators, namely, the breadth and depth of collaboration. The results show that China and the United States are at the center of coronavirus research networks at all three levels, including many endeavors involving single or joint entities. This study demonstrates how governments, public sectors, and private sectors, such as the pharmaceutical industry, can use scientometric analysis to gain insight into the holistic research trends and networks of players in this field, leading to the formulation of strategies to strengthen research and development programs. Furthermore, this approach can be utilized as a visualization and decision support tool for further policy planning, identification and execution of collaboration, and research exchange opportunities. This scientometric process should be directly applicable to other fields.

20.
Sci Rep ; 11(1): 13753, 2021 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-34215824

RESUMEN

Lactic acid bacteria (LAB) are used as a probiotic alternative to antibiotics in livestock production. Microencapsulation technology is widely used for probiotic preservation. A variety of microencapsulation protocols have been proposed and compared based on chemicals and mechanical procedures. This study aimed to develop a double-encapsulated coating from alginate (1.5%) and chitosan (0.5%) by extrusion, emulsion, and spray drying methods using the LAB strains Lactobacillus plantarum strains 31F, 25F, 22F, Pediococcus pentosaceus 77F, and P. acidilactici 72N, and to monitor the basic probiotic properties of the encapsulated prototypes. The final products from each microencapsulation protocol were analysed for their appearance, probiotic properties and viable cell count. Using the spray drying method, particles smaller than 15 µm in diameter with a regular spherical shape were obtained, whereas the other methods produced larger (1.4-52 mm) and irregularly shaped microcapsules. After storage for 6 months at room temperature, the LAB viability of the spray-dried particles was the highest among the three methods. In all the LAB strains examined, the encapsulated LAB retained their probiotic properties in relation to acid-bile tolerance and antibacterial activity. This study highlights the efficacy of double-coating microencapsulation for preserving LAB properties and survival rate, and demonstrates its potential for probiotic application in livestock farms.


Asunto(s)
Composición de Medicamentos , Lactobacillales/química , Lactobacillus plantarum/química , Probióticos/uso terapéutico , Animales , Cápsulas/química , Ganado/microbiología , Viabilidad Microbiana/efectos de los fármacos , Preservación Biológica/métodos
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