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1.
J Mech Behav Biomed Mater ; 146: 106080, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37643540

RESUMEN

The present work describes green-mediated copper oxide nanoparticles as a potential corrosion inhibitor for the dental alloy Ti-6Al-4V. The salt of copper was reduced to metal nanoparticles using Murraya koenigii leaves, which helps with the agglomeration and nanocluster formation through a reduction mechanism. The current synthesis is a single-step process and is cost-effective. The synthesized nanoparticle was characterized using UV, FTIR, XRD, Zeta potential and Particle size analyzer, SEM, and EDX. The particles were then electrodeposited on Ti-6Al-4V alloy, and the corrosion resistivity in the dental medium was analyzed using Electrochemical parameters such as Corrosion current, Corrosion potential, and anodic and cathodic intercepts through the Tafel and Nyquist plots. The synthesized nanoparticles showed characteristic absorbance at 359 nm. FTIR peaks confirm the phytochemical constituents present in the Murraya koenigii that accounts for the formation of nanoparticles. The XRD predicts the crystalline nature, which is further studied using SEM and EDX. The Zeta potential and Particle size analyzer confirms the negative-negative interactive nature of the synthesized CuO NPs. The NPs showed explicit corrosion inhibition properties with an overall inhibition efficiency of 58.15% and 25.6%, respectively. The study confirms the advantage of using Copper Oxide nanoparticles as a potential coating agent in dental implant alloys in increasing its corrosion efficiency.


Asunto(s)
Nanopartículas del Metal , Murraya , Corrosión , Cobre , Aleaciones , Aleaciones Dentales , Óxidos
2.
Sci Rep ; 13(1): 6209, 2023 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-37069316

RESUMEN

In this work, five acrylonitrile adducts were screened for antibacterial activity against Gram-positive Bacillus subtilis, Microbial Type Culture Collection and Gene Bank (MTCC 1305) and Gram-negative Escherichia coli (MTCC 443). Synthesis was followed by aza-Michael addition reaction, where the acrylonitrile accepts an electron pair from the respective amines and results in the formation of n-alkyliminobis-propionitrile and n-alkyliminopropionitrile under microwave irradiation. Characterization of the compounds were performed using Fourier Transform Infrared (FTIR), Proton Nuclear Magnetic Resonance (1H NMR) and Electrospray Ionisation Mass Spectrometry (ESI-MS). The particle size characterization was done by Dynamic Light Scattering (DLS) technique. The antibacterial study showed higher inhibition rate for both Gram-positive and Gram-negative bacteria. The antibacterial ability was found to be dose dependent. The minimum inhibitory concentration against both bacteria were found to be 1, 3, 0.4, 1, 3 µl/ml for E. coli and 6, 6, 0.9, 0.5, 5 µl/ml for B. subtilis. Time-kill kinetics evaluation showed that the adducts possess bacteriostatic action. Further it was evaluated for high-throughput in vitro assays to determine the compatibility of the adducts for drug delivery. The haemolytic and thrombolytic activity was analysed against normal mouse erythrocytes. The haemolytic activity showed prominent results, and thereby projecting this acrylonitrile adducts as potent antimicrobial and haemolytic agent.


Asunto(s)
Acrilonitrilo , Antiinfecciosos , Animales , Ratones , Antibacterianos/farmacología , Antibacterianos/química , Acrilonitrilo/farmacología , Fibrinolíticos , Escherichia coli , Bacterias Gramnegativas , Antiinfecciosos/farmacología , Pruebas de Sensibilidad Microbiana , Bacillus subtilis
3.
Adv Exp Med Biol ; 1052: 63-74, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29785481

RESUMEN

The present study aims at synthesizing gelatin A-pectin complex coacervates and encapsulation of theophylline in the polymer system. Variation and optimization of different reaction parameters such as pH, ratio between the polymers and cross-linker concentration was carried out to attain higher product yield. Relative viscosity, turbidity and UV-visible measurements were done for optimization. The optimum ratio between gelatin A-pectin was fixed at weight ratio 42:8 and pH=3.5. It was further observed that adhesion between the microcapsules decreased by the use of sodium carboxymethyl cellulose (SCMC) to the coacervate. The synthesized microcapsules were characterized by using spectroscopic techniques to assess their formation, drug loading and chemical interaction between theophylline and coacervate. Scanning electron microscopy (SEM) revealed the formation of microcapsules. Study relating to the encapsulation efficiency and swelling of the complex coacervates were also carried out.


Asunto(s)
Cápsulas/química , Gelatina/química , Pectinas/química , Polímeros/química , Teofilina/química , Coloides/química , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Concentración de Iones de Hidrógeno , Espectroscopía Infrarroja por Transformada de Fourier , Teofilina/farmacología , Viscosidad
4.
Adv Colloid Interface Sci ; 239: 136-145, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27296302

RESUMEN

Polysaccharide-protein complex coacervates are amongst the leading pair of biopolymer systems that has been used over the past decades for encapsulation of numerous active ingredients. Complex coacervation of polysaccharides and proteins has received increasing research interest for the practical application in encapsulation industry since the pioneering work of complex coacervation by Bungenburg de Jong and co-workers on the system of gelatin-acacia, a protein-polysaccharide system. Because of the versatility and numerous potential applications of these systems essentially in the fields of food, pharmaceutical, cosmetics and agriculture, there has been intense interest in recent years for both fundamental and applied studies. Precisely, the designing of the micronscale and nanoscale capsules for encapsulation and control over their properties for practical applications garners renewed interest. This review discusses on the overview of polysaccharide-protein complex coacervates and their use for the encapsulation of diverse active ingredients, designing and controlling of the capsules for delivery systems and developments in the area.


Asunto(s)
Polisacáridos/química , Proteínas/química , Electricidad Estática , Animales , Cápsulas , Humanos
5.
J Ind Microbiol Biotechnol ; 43(10): 1373-86, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27514666

RESUMEN

Human interleukin-3 (hIL-3) is a therapeutically important cytokine involved in the maturation and differentiation of various cells of the immune system. The codon-optimized hIL-3 gene was cloned in fusion with the N-terminus α-mating factor signal peptide of Saccharomyces cerevisiae under an inducible alcohol oxidase 1 (AOX1) and constitutive glyceraldehyde-3-phosphate dehydrogenase (GAP) promoter. A Zeocin concentration up to 2000 mg/L was used to select hyper-producers. The shake flask cultivation studies in the Pichia pastoris GS115 host resulted a maximum recombinant hIL-3 expression level of 145 mg/L in the extracellular medium under the control of AOX1 promoter. The batch fermentation strategy allowed us to attain a fairly pure glycosylated hIL-3 protein in the culture supernatant at a final concentration of 475 mg/L with a high volumetric productivity of 4.39 mg/L/h. The volumetric product concentration achieved at bioreactor level was 3.28 folds greater than the shake flask results. The 6x His-tagged protein was purified using Ni-NTA affinity chromatography and confirmed further by western blot analysis using anti-6x His tag antibody. The glycosylation of recombinant hIL-3 protein was confirmed in a PNGase F deglycosylation reaction where it showed a molecular weight band pattern similar to E. coli produced non-glycosylated hIL-3 protein. The structural properties of recombinant hIL-3 protein were confirmed by CD and fluorescence spectroscopy where protein showed 40 % α-helix, 12 % ß-sheets with an emission maxima at 343 nm. MALDI-TOF-TOF analysis was used to establish the protein identity. The biological activity of purified protein was confirmed by the human erythroleukemia TF-1 cell proliferation assay.


Asunto(s)
Interleucina-3/biosíntesis , Pichia/genética , Oxidorreductasas de Alcohol/genética , Reactores Biológicos , Codón , Fermentación , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Humanos , Interleucina-3/química , Interleucina-3/genética , Pichia/metabolismo , Regiones Promotoras Genéticas , Señales de Clasificación de Proteína/genética , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo
6.
Appl Microbiol Biotechnol ; 100(23): 9979-9994, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27342246

RESUMEN

Human interleukin-7 (hIL-7) is a therapeutically important cytokine involved in lymphocyte development and survival. In previous reports, a uniformly poor expression of hIL-7 has been shown in Escherichia coli host with the problem of inclusion body formation. In this study, the role of codon optimization and N-terminus blocking using various solubility enhancer fusion tags was explored to improve its soluble expression. The use of codon optimization strategy improved its expression to 80 ± 5 mg/L at shake flask level. The utilization of pelB leader sequence resulted in an unprocessed protein in the form of cytoplasmic inclusion bodies with lower expression yields. The N-terminus fusion of small ubiquitin-like modifier (SUMO), thioredoxin (Trx), and NusA tags increased the expression in the range of 90-140 mg/L, where >90 % of the fusion protein was obtained in soluble form. The fed-batch fermentation of SUMO-tagged hIL-7 protein was optimized at bioreactor level, where a high volumetric product concentration of 2.65 g/L was achieved by controlling the plasmid segregation instability using high antibiotic concentration. The specific product yield (YP/X) and volumetric product concentration were 1.38 and 2.55-fold higher compared to batch results, respectively. A preparative scale affinity chromatography resulted in a high recovery yield of 50.6 mg/L with ∼90 % purity. The conformational property of purified recombinant hIL-7 from CD spectroscopy showed a typical helical structure with 31.5 % α-helix and 26.43 % ß-sheet. The biological activity of purified protein was tested using IL-7-dependent murine immature B lymphocyte (2E8) cell line by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide salt (MTT) assay, where it showed a similar biological activity as standard control.


Asunto(s)
Escherichia coli/metabolismo , Expresión Génica , Interleucina-7/metabolismo , Ingeniería de Proteínas , Proteínas Recombinantes de Fusión/metabolismo , Solubilidad , Animales , Linfocitos B/efectos de los fármacos , Linfocitos B/fisiología , Técnicas de Cultivo Celular por Lotes , Reactores Biológicos/microbiología , Proliferación Celular , Cromatografía de Afinidad , Escherichia coli/genética , Interleucina-7/química , Interleucina-7/genética , Ratones , Conformación Proteica , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Análisis Espectral
7.
Int J Biol Macromol ; 83: 50-60, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26631635

RESUMEN

Streptokinase is a biological macromolecule involved in dissolution of fibrin blood clot and favourably used in various clinical applications. This protein is poorly expressed in soluble form due to its toxic effects on host physiology. The extracellular expression of recombinant streptokinase (SK) with and without 6xHis tag was obtained by cloning its gene under the α-mating factor signal sequence and alcohol inducible AOX1 promoter. Host-vector combinations were optimized to select a hyper producer. From shake flask optimization studies, a maximum expression of 582 mg/L of rSK (non-tagged) and 538 mg/L of rSK-His (His-tagged) protein was obtained when cells were induced at OD600 of 20. The high cell density fermentation increased the volumetric product concentration of rSK-His to a level of 4.25 g/L with a 7.9 folds increase from shake flask results. The specific product yield (YP/X) was 49.75 mg/g DCW along with a high volumetric productivity of 57.43 mg/L/h. The protein was predicted to have 15.43% α-helix and 26.43% ß-sheet with tryptophan emission maxima of around 347 nm. The highest specific activity of rSK-His was 64,903 IU/mg with 1.48 folds purification whereas specific activity of rSK was 55,240 IU/mg with 1.22 folds purification.


Asunto(s)
Pichia/genética , Pichia/metabolismo , Estreptoquinasa/genética , Estreptoquinasa/metabolismo , Técnicas de Cultivo Celular por Lotes/métodos , Clonación Molecular/métodos , Fermentación/genética , Expresión Génica/genética , Factor de Apareamiento , Péptidos/genética , Péptidos/metabolismo , Regiones Promotoras Genéticas/genética , Señales de Clasificación de Proteína/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
8.
Oman Med J ; 27(1): e030, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28861184

RESUMEN

We report the first case of a giant serous cystadenoma approximately 7.5kg in weight in a 28-year old primigravida at 8 weeks of gestation which was successfully excised laparoscopically. Postoperatively, she had a quick recovery and she was discharged on post op day 3 with an intact pregnancy and no complications. This is the largest ovarian cyst in early pregnancy that has been ever reported from our hospital. We also believe this cyst to be the largest cyst in early pregnancy ever reported in the literature that has been managed by Laparoscopy.

9.
Drug Dev Ind Pharm ; 36(1): 56-63, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19681667

RESUMEN

BACKGROUND: Microspheres of gelatin-A and κ-carrageenan were prepared by using genipin, a naturally occurring crosslinker, and sunflower oil as reaction media. METHOD: The variations in the size of the microspheres formed by varying the amount of surfactant (0.33-1.0 g/g of polymer), polymer (1.5-3.0 g), and crosslinker (0.2-0.8 mmol) were studied by scanning electron microscopy. The encapsulation of isoniazid was carried out by absorption. The isoniazid content in the prepared microspheres was determined. The release characteristic of isoniazid was also studied at pH values 1.2 and 7.4 by using UV-spectrophotometer. RESULTS: Characterization of the isoniazid-loaded microspheres was carried out by using Fourier transform infrared spectrophotometry, differential scanning calorimetry, and X-ray diffractometery.


Asunto(s)
Carragenina/química , Gelatina/química , Iridoides/química , Isoniazida/administración & dosificación , Antituberculosos/administración & dosificación , Rastreo Diferencial de Calorimetría , Reactivos de Enlaces Cruzados/química , Portadores de Fármacos/química , Electrólitos/química , Concentración de Iones de Hidrógeno , Microesferas , Tamaño de la Partícula , Aceites de Plantas/química , Espectroscopía Infrarroja por Transformada de Fourier , Aceite de Girasol , Tensoactivos/química , Difracción de Rayos X
10.
Exp Toxicol Pathol ; 62(5): 461-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19581075

RESUMEN

BACKGROUND: Cervical cancer is the second most common cause of cancer death in women. We have demonstrated previously that zerumbone (ZER) has an anti-cancer effect towards human cervical cancer cells (HeLa). METHODS: Anti-cancer properties of ZER were investigated using female Balb/c mice exposed prenatally to diethylstilboestrol. Female offspring have been treated with ZER (4, 8 and 16 mg/kg), normal saline and cisplatin (10mg/kg; positive control). The anti-cancer properties of ZER were evaluated using histopathology, TdT-mediated dUTP nick end labeling (TUNEL) Assay and immunohistochemical staining of Bcl-2-associated X protein (Bax), a key protein in mitochondrial pathway of apoptosis. In addition, laser capture microdissection microscopy isolated RNA was amplified using reverse transcriptase polymerase chain reaction (RT-PCR) based on the specific primer of B-cell lymphoma 2 (Bcl-2). RESULTS: Treatment with ZER resulted (P<0.05, chi(2) statistics) in the regression of cervical intraepithelial neoplasia (CIN) resembling cisplatin effect (10mg/kg). TUNEL micrographs showed the absence of apoptosis in cancerous tissues treated with normal saline compared to ZER and cisplatin where abundant apoptotic cells were noticed. A post hoc analysis showed a significant (P<0.01) difference in mean percentage of apoptosis between normal saline treatment (0%), ZER (15.7%) and cisplatin (21.7%). Immunohistochemical staining of Bax protein revealed that ZER modulates the expression of this apoptosis marker. Administration of ZER has also modulated the expression of Bcl-2 gene. CONCLUSION: These findings showed that ZER induces apoptosis efficiently in cervical tissues from female Balb/c mice treated prenatally with diethylstilboestrol. This suggested that ZER, a plant-derived compound, could be introduced as a new chemo-preventive agent for CIN in future.


Asunto(s)
Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Sesquiterpenos/uso terapéutico , Displasia del Cuello del Útero/prevención & control , Neoplasias del Cuello Uterino/prevención & control , Animales , Carcinógenos/toxicidad , Dietilestilbestrol/toxicidad , Femenino , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Ratones , Ratones Endogámicos BALB C , Microscopía Confocal , Mitocondrias/efectos de los fármacos , Embarazo , Efectos Tardíos de la Exposición Prenatal , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias del Cuello Uterino/inducido químicamente , Neoplasias del Cuello Uterino/patología , Displasia del Cuello del Útero/inducido químicamente , Displasia del Cuello del Útero/patología
11.
AAPS PharmSciTech ; 10(4): 1412-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19937282

RESUMEN

The ratio of gelatin to sodium carboxymethyl cellulose (SCMC) at which maximum yield was obtained was optimized. This optimized ratio of gelatin to SCMC along with other parameters was used to prepare microparticles of different sizes. Vegetable oil was used as emulsion medium. Effect of various factors like amount of surfactant, concentration of polymer on the formation, and size of the microparticles was investigated. These microparticles were used as carrier for isoniazid. Among different cross-linkers, glutaraldehyde was found to be the most effective cross-linker at the temperature and pH at which the reaction was carried out. The loading efficiency and release behavior of loaded microparticles were found to be dependent on the amount of cross-linker used, concentration of drug, and time of immersion. Maximum drug loading efficiency was observed at higher immersion time. The release rate of isoniazid was more at higher pH compared to that of at lower pH. The sizes of the microparticles were investigated by scanning electron microscope. In all the cases, the microparticles formed were found spherical in shape except to those at low stirring speed where they were agglomerated. Fourier transform infrared study indicated the successful incorporation of isoniazid into the microparticles. Differential scanning calorimetry study showed a molecular level dispersion of isoniazid in the microparticles. X-ray diffraction study revealed the development of some crystallinity due to the encapsulation of isoniazid.


Asunto(s)
Antituberculosos/administración & dosificación , Carboximetilcelulosa de Sodio/administración & dosificación , Gelatina/administración & dosificación , Isoniazida/administración & dosificación , Rastreo Diferencial de Calorimetría , Preparaciones de Acción Retardada , Isoniazida/química , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
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