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1.
Environ Res ; 214(Pt 3): 114001, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35934144

RESUMEN

Polyhydroxyalkanoates (PHA), especially poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is considered as the most suitable candidate to replace petrochemical plastics. However, the high production cost and the composition of the monomers in the copolymer are the major constraints in production. The 3-hydroxyvalerate (3HV) rich copolymers are ideal for various applications due to their lower melting points, improved elasticity, and ductility. Haloferax mediterranei is a suitable microorganism for the production of biopolymer PHBV from biowaste. Nevertheless, the potential of H. mediterranei cultivated on food waste as sustainable substrate and levulinic acid as an inducer has not been explored for PHBV production. This study aims at the valorization of food waste as low-cost substrate and evaluation of effect of levulinic acid in the production and composition of PHBV using H. mediterranei. Shake-flask fermentations using different concentrations of salt, glucose and levulinic acid were first performed to optimize the cultivation conditions. The highest growth of the halophile was observed at salt concentration of 15% and glucose of concentration 10 g/L. Under optimized growth conditions, H. mediterranei was cultivated for PHBV production in fed-batch bioreactor with pulse fed levulinic acid. The maximum biomass of 3.19 ± 0.66 g/L was achieved after 140 h of cultivation with 3 g/L of levulinic acid. A decrease in H. mediterranei growth was noticed with the increase in levulinic acid concentration in the range of 3-10 g/L. The overall yield of PHBV at 3, 5, 7 and 10 g/L of levulinic acid were 18.23%, 56.70%, 31.54%, 21.29%, respectively. The optimum concentration of 5 g/L of levulinic acid was found to produce the maximum yield of 56.70% PHBV with 18.55 mol% 3HV content. A correlation between levulinic acid concentrations and PHBV production established in this study can serve as an important reference for future large-scale production.


Asunto(s)
Haloferax mediterranei , Polihidroxialcanoatos , Eliminación de Residuos , Alimentos , Glucosa , Ácidos Levulínicos , Poliésteres/química , Polihidroxialcanoatos/química
2.
Life Sci ; 346: 122616, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38599316

RESUMEN

Liposomes, as a colloidal drug delivery system dating back to the 1960s, remain a focal point of extensive research and stand as a highly efficient drug delivery method. The amalgamation of technological and biological advancements has propelled their evolution, elevating them to their current status. The key attributes of biodegradability and biocompatibility have been instrumental in driving substantial progress in liposome development. Demonstrating a remarkable ability to surmount barriers in drug absorption, enhance stability, and achieve targeted distribution within the body, liposomes have become pivotal in pharmaceutical research. In this comprehensive review, we delve into the intricate details of liposomal drug delivery systems, focusing specifically on their pharmacokinetics and cell membrane interactions via fusion, lipid exchange, endocytosis etc. Emphasizing the nuanced impact of various liposomal characteristics, we explore factors such as lipid composition, particle size, surface modifications, charge, dosage, and administration routes. By dissecting the multifaceted interactions between liposomes and biological barriers, including the reticuloendothelial system (RES), opsonization, enhanced permeability and retention (EPR) effect, ATP-binding cassette (ABC) phenomenon, and Complement Activation-Related Pseudoallergy (CARPA) effect, we provide a deeper understanding of liposomal behaviour in vivo. Furthermore, this review addresses the intricate challenges associated with translating liposomal technology into practical applications, offering insights into overcoming these hurdles. Additionally, we provide a comprehensive analysis of the clinical adoption and patent landscape of liposomes across diverse biomedical domains, shedding light on their potential implications for future research and therapeutic developments.


Asunto(s)
Membrana Celular , Sistemas de Liberación de Medicamentos , Liposomas , Animales , Humanos , Membrana Celular/metabolismo , Distribución Tisular
3.
J Control Release ; 355: 709-729, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36805872

RESUMEN

Novel therapies and drug delivery systems (DDS) emphasis on localized, personalized, triggered, and regulated drug administration have heavily implicated electrically responsive DDS. An ideal DDS must deliver drugs to the target region at therapeutically effective concentrations to elicit a pharmacological response, resulting in better prophylaxis of the disease and the treatment. Biodegradable polymers are frequently employed for in-vivo long-term release; however, dose dumping can be anticipated. As a result, current DDSs can be tagged as dubbed "Smart Biomaterials" since they only focus on an on-demand cargo release in response to a trigger or stimulation. These organic materials have been recognized for their metal-like conductivity, as well as their mechanical stability and ease of production. These biomaterials can be programmed to respond to both internal and external stimuli. External pulsed triggers are required for extrinsic stimuli-responsive materials, whereas intrinsic stimuli-responsive materials rely on localized changes in the tissue environment. Furthermore, these materials have the ability to deliver active pharmaceutical agents at a varied concentration levels and across a broad spectrum of action. Drug delivery, biomedical implant technology, biosensor technology, and tissue engineering can be listed as a few prominent applications that have sparked immense interest for conductive polymers-based research and advancements in academia as well as in industry. This review comprehensively covers a cutting-edge collection of electrically conductive polymers and composites, and provide detailed insights of recent trends and advancements allied to conductive polymers for their potential applicability in an array of diverse meadows primarily focusing on drug delivery, biosensing and therapeutics. Furthermore, progressions in their synthesis, structural and functional properties have been presented in conjunction with futuristic directions for the smooth clinical translations.


Asunto(s)
Polímeros , Polímeros de Estímulo Receptivo , Polímeros/química , Sistemas de Liberación de Medicamentos , Materiales Biocompatibles/química , Ingeniería de Tejidos/métodos
4.
Bioresour Technol ; 320(Pt A): 124278, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33099158

RESUMEN

The aim of this work was to study the pyrolysis of waste biomass and plastics and use the produced biochar for the removal of heavy metals from aqueous solution. The batch experiments of Fe, Ni, Cu, Cr, Cd and Pb with biochars and plastic chars were carried for determining the effects of various experimental parameters (feedstock, contact time, adsorbent dose, pH and pyrolysis temperature). The isothermal sorption models demonstrated that the sorption capacities of biochars are higher in comparison to the plastic chars. The maximum removal efficiency shown by biochars and plastic chars at pH 4 was 99.86% and 99.93%, respectively. Both the carbon materials are thereby recognized as an environment-friendly and efficient pollutant control material at various studied parameters.


Asunto(s)
Metales Pesados , Pirólisis , Adsorción , Biomasa , Carbón Orgánico , Plásticos
5.
J Ethnopharmacol ; 206: 376-392, 2017 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-28502905

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Careya arborea Roxb. (Lecythidaceae) is a large tree found throughout India in deciduous forests and grasslands. C. arborea is traditionally used in tumors, inflammation, anthelmintic, bronchitis, epileptic fits, astringents, antidote to snake-venom, skin disease, diarrhea, dysentery with bloody stools, dyspepsia, ulcer, tooth ache, and ear pain. AIM OF THE STUDY: In our previous work, the methanolic extract of Careya arborea stem bark showed significant anti-inflammatory activity. As a continuity of that work, this study aimed at the isolation and evaluation of the anti-inflammatory effect of coumaroyl lupendioic acid, a new lupane-type triterpene from Careya arborea stem bark. Further, to give an insight into the underlying mechanism of action of the compound on the modulation of proinflammatory mediators. MATERIALS AND METHODS: Methanolic extract of Careya arborea stem bark was suspended in water, and sequentially fractionated with n-hexane and ethyl acetate. Further ethyl acetate fraction was subjected to medium pressure liquid chromatography (MPLC) to isolate the active molecules. The isolated compounds were characterized by the various spectral techniques namely UV, IR, 1H NMR, 13C NMR, DEPT, 1H-1H COSY, HMBC and Mass spectral techniques. In vitro COX-1 and COX-2 enzyme inhibition assays using human whole blood was performed to investigate the inhibitory effect of the isolated compounds. The resulted potent COX-2 inhibitor of the isolated constituents compound 5, designated as coumaroyl lupendioic acid (CLA), was investigated in carrageenan induced inflammation and its effect was also compared with betulinic acid (BA) at the doses of 10 and 20mgkg-1, p.o. using indomethacin and celecoxib (10 and 20mgkg-1, p.o., respectively) as reference drugs. The effect of CLA on the production of NO, MPO, PGE2, TNF-α, IL-1ß and IL-6 were assessed. In addition, the histopathology and immunohistochemistry (NF-Ò¡B, COX-2 and TNF-α protein expression) in paw tissues were also carried out. RESULTS: The chromatographic fractionation of the methanolic extract resulted in isolation of six new derivatives of lupane type triterpenes for the first time from the stem bark of C. arborea; 3ß-hydroxy-lup-5,20 (29),21-trien-28-oic acid (Compound 1), 1, 3, 13, 16-tetrahydroxy-lup-9(11), 20(29)-diene-28-oic acid (Compound 2), 1, 7-di hydroxy betulinic acid (Compound 3), 3ß-O-dihydrocinnamyl betulinic acid (Compound 4), 3ß-O-trans-coumaryl-lup-6, 9(11), 20(29)-triene-27, 28-dioic acid (Compound 5), 16ß-hydroxy-2, 3-seco-lup-5, 20(29)-dien-2, 3, 28-trioic acid (Compound 6). Among the all isolated compounds 3ß-O-trans-coumaryl-lup-6, 9(11), 20(29)-triene-27, 28-olioic acid designated as coumaroyl lupendioic acid (CLA) showed higher COX-2 selectivity which is comparable to reference drug (celecoxib). CLA significantly reduced carrageenan induced inflammation whereas CLA revealed greater effect as compared to BA at the similar corresponding doses. Moreover, CLA significantly inhibited pro-inflammatory mediators elevated by carrageenan. CLA also preserved the tissue architecture as evidenced by the histopathology. Furthermore, immunohistochemical studies revealed that CLA significantly down regulated NF-Ò¡B, COX-2 and TNF-α protein expression. CONCLUSION: The study gives an insight into the molecular mechanisms of coumaroyl lupendioic acid and suggests that the down-regulations of proinflammatory mediators provide credence to the ethno botanical use of the plant in the management of inflammation.


Asunto(s)
Modelos Animales de Enfermedad , Mediadores de Inflamación/antagonistas & inhibidores , Inflamación/tratamiento farmacológico , Lecythidaceae/química , Extractos Vegetales/farmacología , Animales , Extractos Vegetales/uso terapéutico , Ratas , Ratas Wistar , Análisis Espectral
6.
Int J Clin Pediatr Dent ; 9(1): 39-44, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27274154

RESUMEN

BACKGROUND: Dermatoglyphics refers to study of the intricate dermal ridge configurations on the skin covering the palmar and plantar surfaces of hand and feet. The basis of considering dermatoglyphic patterns as genetic marker for dental caries is that the epithelium of finger buds as well as enamel has ectodermal origin, and both develop at the same time of intrauterine life. AIM: To assess the relationship between fingerprint patterns and dental caries among preschool children of Lucknow city. STUDY DESIGN: This study was of cross-sectional design. MATERIALS AND METHODS: The study group comprised 512 preschool children 2-6 years of age. The prevalence of caries was recorded using "Dentition status and treatment needs" (WHO basic oral health assessment form, 1997). They were divided into three groups as follows: Group I (dmft score = 0-2), group II (dmft score = 3-4) and group III (dmft score ≥5). The handprints of each child were taken using a stamp pad. The fingertip patterns were analyzed according to the classical method and were classified according to the topological method. The frequency of occurrence of type of dermatoglyphic pattern on fingertip of each digit was noted. STATISTICS: Chi-square test was used to test the significant difference in proportions. Means were compared using Student's t-test and analysis of variance (ANOVA) or F-test. RESULTS: Subjects belonging to groups II and III showed maximum occurrence of whorl pattern on all digits. Group I subjects had maximum occurrence of arch pattern. All the variables had statistically significant value, with a degree of divergence of specific dermatoglyphic patterns among all three groups. CONCLUSION: The dental caries susceptibility of an individual increased with incidence of whorl pattern and it decreased with incidence of arch pattern. How to cite this article: Singh E, Saha S, Jagannath GV, Singh S, Saha S, Garg N. Association of Dermatoglyphic Peculiarities with Dental Caries in Preschool Children of Lucknow, India. Int J Clin Pediatr Dent 2016;9(1):39-44.

7.
J Clin Diagn Res ; 9(1): ZC35-8, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25738083

RESUMEN

AIM: To assess the effectiveness of outreach program in the 12 years school going children during a three year follow up period of Lucknow city. MATERIALS AND METHODS: A random sample of 298 school going children of age 12 years was drawn from adopted schools of Lucknow. Three years later the same population was re-examined with a population of 242 children of 15 y age group. The oral health status of these children was accessed by using WHO 1997 profoma. RESULTS: Significantly (p<0.001) higher proportion of children had healthy gingival, healthy periodontal status after three years. The difference in regard to crowding in the incisal segment in 2010 and 2013 was statistically highly significant (p<0.001). CONCLUSION: The findings of the study showed that after providing regular dental check up and treatment camps in the three adopted schools after three year follow up study from 2010-2013 showed positive impact on the children oral hygiene status and has been estimated to be on the more positive aspect in future also.

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