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1.
Int J Biol Macromol ; 165(Pt A): 333-345, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32980413

RESUMEN

The current study aims to check various behavioural, developmental, cytotoxic, and genotoxic effects of Fe3O4-GG nanocomposite (GGNCs) on Drosophila melanogaster. Fe3O4 nanoparticles were prepared by the chemical co-precipitation method and cross-linked with guargum nanoparticles to prepare the nanocomposites. The nanocomposites were characterized by using transmission electron microscopy (TEM), X-ray diffraction (XRD), and FTIR techniques. To investigate the biomolecular interaction, GGNCs was further tagged with Fluorescein isothiocyanate. Various concentrations of nanocomposites were mixed with the food and flies were allowed to complete the life cycle. The life cycle of the flies was studied as a function of various concentrations of GGNCs. The 1st instar larvae after hatching from the egg start eating the food mixed with GGNCs. The 3rd instar larvae were investigated for various behavioural and morphological abnormalities within the gut. The 3rd instar larva has defective crawling speed, crawling path, and more number of micronuclei within the gut. Similarly, in adult flies thermal sensitivity, climbing behaviour was found to be altered. In adult flies, a significant reduction in body weight was found which is further correlated with variation of protein, carbohydrate, triglyceride, and antioxidant enzymes. Altogether, the current study suggests GGNCs as a non-genotoxic nanoparticle for various biological applications.


Asunto(s)
Materiales Biocompatibles Revestidos , Daño del ADN , Óxido Ferrosoférrico , Galactanos , Mananos , Gomas de Plantas , Animales , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Drosophila melanogaster , Óxido Ferrosoférrico/química , Óxido Ferrosoférrico/farmacología , Galactanos/química , Galactanos/farmacología , Larva/crecimiento & desarrollo , Mananos/química , Mananos/farmacología , Gomas de Plantas/química , Gomas de Plantas/farmacología
2.
Carbohydr Res ; 491: 107983, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32229325

RESUMEN

Herein we report the synthesis of newer guar gum cinnamate esters (GGC) following a Hofmeister cation guided homogeneous phase reaction. High degree of substitution (DS) guar gum cinnamate was obtained using, cinnamic acid halide reactant at a 1:3 M ratio. The biopolymer was fully characterized in FT-IR,13C NMR, XRD and thermal analysis. Nanoparticles were further developed in a facile ouzo solvent diffusion technique. SEM studies confirmed quasi spherical shape of the nanoparticles (GGCN) with an average size of 200 nm. Nanoparticles GGCN, expressed antibacterial activity against water borne gram negative and gram positive bacteria. The MIC was recorded at 300 µg mL-1against Escherichia coli and 500 µg mL-1against Staphylococcus aureus. Bacterial contact killing was confirmed from the bacterial morphology studies in SEM. Thus, nanoparticles from GGC may be employed for bacterial killing and water decontamination.


Asunto(s)
Antibacterianos/farmacología , Cinamatos/farmacología , Escherichia coli/efectos de los fármacos , Ésteres/farmacología , Galactanos/farmacología , Mananos/farmacología , Nanopartículas/química , Gomas de Plantas/farmacología , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Cinamatos/síntesis química , Cinamatos/química , Relación Dosis-Respuesta a Droga , Ésteres/síntesis química , Ésteres/química , Galactanos/síntesis química , Galactanos/química , Mananos/síntesis química , Mananos/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Gomas de Plantas/síntesis química , Gomas de Plantas/química , Relación Estructura-Actividad , Microbiología del Agua
3.
Int J Biol Macromol ; 120(Pt B): 1823-1833, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30287366

RESUMEN

The present work reports the synthesis of new generation semi-interpenetrating (s-IPN) hydrogels from carboxymethyl guar gum (CMGG) and gelatin with enhanced gel properties for suitable drug delivery applications. Hydrogels are three dimensional polymer networks which respond to water and ion interactions. Irreversible s-IPN hydrogels were prepared by CMGG interactions in gelatin and characterized in FT-IR, SEM and thermal studies. CMGG was synthesized by Hofmeister ion guided homogeneous phase reactions. The swelling kinetics of the newer s-IPN hydrogels followed Schott's pseudo second order model. Furthermore, the hydrogels were hemocompatible, non-cytotoxic and appropriate for applications in physiological environment. Model drug ciprofloxacin was loaded within the hydrogels and the drug release was found to be a combination of both diffusion and hydrogel degradation. New generation s-IPN biopolymer hydrogels of carboxymethyl guar gum and gelatin holds promise for its application as sustained drug delivery device or alternatively as hydrogel sorbents for bio-toxins and molecules of biomedical importance.


Asunto(s)
Ciprofloxacina/química , Portadores de Fármacos/química , Galactanos/química , Gelatina/química , Hidrogeles/química , Mananos/química , Gomas de Plantas/química , Animales , Preparaciones de Acción Retardada , Portadores de Fármacos/toxicidad , Hidrogeles/toxicidad , Cinética , Ensayo de Materiales , Fenómenos Mecánicos , Ratones , Células 3T3 NIH , Temperatura
4.
Int J Biol Macromol ; 95: 818-825, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27923567

RESUMEN

A carbonyl reductase (cr) gene from Candida glabrata CBS138 has been heterologously expressed in cofactor regenerating E. coli host to convert Ethyl-4-chloro-3-oxobutanoate (COBE) into Ethyl-4-chloro-3-hydroxybutanoate (CHBE). The CR enzyme exhibited marked velocity at substrate concentration as high as 363mM with highest turnover number (112.77±3.95s-1). Solitary recombineering of such catalytic cell reproduced CHBE 161.04g/L per g of dry cell weight (DCW). Introduction of combinatorially engineered crp (crp*, F136I) into this heterologous E. coli host yielded CHBE 477.54g/L/gDCW. Furthermore, using nerolidol as exogenous cell transporter, the CHBE productivity has been towered to 710.88g/L/gDCW. The CHBE production has thus been upscaled to 8-12 times than those reported so far. qRT-PCR studies revealed that both membrane efflux channels such as acrAB as well as ROS scavenger genes such as ahpCF have been activated by engineering crp. Moreover, membrane protecting genes such as manXYZ together with solvent extrusion associated genes such as glpC have been upregulated inside mutant host. Although numerous proteins have been investigated to convert COBE to CHBE; this is the first approach to use engineering triad involving crp engineering, recombinant DNA engineering and transporter engineering together for improving cell performance during two-phase biocatalysis.


Asunto(s)
Oxidorreductasas de Alcohol/genética , ADN Ribosómico/genética , Escherichia coli/citología , Escherichia coli/genética , Ingeniería de Proteínas , Acetatos/farmacología , Acetoacetatos/metabolismo , Biotransformación/efectos de los fármacos , Butiratos/metabolismo , Candida glabrata/enzimología , Candida glabrata/genética , Relación Dosis-Respuesta a Droga , Escherichia coli/metabolismo , Sesquiterpenos/farmacología
5.
Carbohydr Polym ; 134: 30-7, 2015 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-26428096

RESUMEN

This work is meant for environmentally friendly synthesis and functional evaluation of silver nanoparticles in a newer cationic guar biopolymer (GGAA). Assembly of molecules in lower size range (∼ 10 nm) was attained in a biopolymer entrapped bottom-up synthesis. Guar gum is a filming biopolymer. Nanoparticles encaged in cationic guar (GGAgnC) were preserved as films for months without any significant effect on particle size, distribution or plasmonic intensity. The new nano-bio-composite and films were characterized fully in FTIR, XRD, SEM and TEM studies. Silver nanoparticles induced surface water repellency remarkably and lowered moisture permeability. GGAgnC film water contact angle was recorded as 115° while, that in case of GGAA was 59°. GGAgnC expressed intense antimicrobial activity when tested against a range of microorganisms. Immobilized silver nanoparticles in GGAA can feasibly be used as filming microbicidals suitable for textiles, packaging and biomedical device applications.


Asunto(s)
Antibacterianos/química , Galactanos/química , Tecnología Química Verde , Mananos/química , Nanopartículas del Metal/química , Gomas de Plantas/química , Plata/química , Aminación , Antibacterianos/síntesis química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Cationes/síntesis química , Cationes/química , Cationes/farmacología , Galactanos/síntesis química , Galactanos/farmacología , Tecnología Química Verde/métodos , Mananos/síntesis química , Mananos/farmacología , Nanopartículas del Metal/ultraestructura , Nanotecnología/métodos , Gomas de Plantas/síntesis química , Gomas de Plantas/farmacología , Plata/farmacología , Vapor , Microbiología del Agua
6.
Mater Sci Eng C Mater Biol Appl ; 46: 521-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25492017

RESUMEN

Guar gum (GG) is a galactomannan obtained from the seeds of Cyamopsis tetragonoloba. GG polysaccharide is used in a range of technology arenas and its properties in water environment elicited a lot of interest. We report a simple acid hydrolysis technique to derive water dispersible spherical nanoparticles from GG for the first time without any stabilizing surfactant. The particles demonstrated colloidal stability and were observed to carry negative surface charges in aqueous environment. The TEM study of guar gum nanoparticles (GGn) indicated a size range of 30-80 nm with a mean at 48.8 nm. Mineral acid at apposite concentration have apparently solubilized the amorphous regions of the polymer chain leaving the crystalline parts. GGn were further covalently functionalized in aqueous environment with fluorescein isothiocyanate (FITC) using a hydroxy-propyl amine spacer group. Nanoparticle fluorescence intensity can be modulated with pH changes and a significant augmentation in the intensity was noticed at the physiologically relevant range of 6-8. New fluorescently labeled nanoparticles have potential for applications in bioimaging, biomolecular interaction studies and as a pH sensing probe in sub cellular environment.


Asunto(s)
Galactanos , Mananos , Nanopartículas , Gomas de Plantas , Agua/química , Colorantes Fluorescentes , Microscopía Electrónica de Transmisión , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Tensoactivos/análisis , Difracción de Rayos X
7.
J Minim Access Surg ; 10(2): 93-6, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24761086

RESUMEN

Double gallbladder is a rare embryological anomaly of clinical significance. Despite availability of modern imaging, only 50% of recently reported cases had preoperative diagnosis, which is desirable in every case to avoid serious operative complications. Double pathology in double gallbladder is extremely rare with only 3 reporting's available till date to the best of author's knowledge. With a preoperative diagnosis of double gallbladder, laparoscopic cholecystectomy can be safely and successfully performed with meticulous dissection, aided by operative cholangiogram. However in all such attempts a lower threshold should be kept for conversion to open surgery. Awareness about this anomaly amongst radiologists and surgeons is of crucial importance. Double gallbladder does not present with any specific symptom, neither it increases disease possibility in either lobe. Prophylactic cholecystectomy has no role in asymptomatic cases diagnosed accidentally. Author reports a case of a symptomatic young male with double gallbladder who presented with short history of dyspepsia, abdominal pain and fever. Definite preoperative diagnosis was reached with ultrasound scan and magnetic resonance cholangio pancreatography and subsequently dealt with laparoscopically. Calculous cholecystitis affected one lobe and acalculous empyema the other. While the 1st lobe drained though a cystic duct into common bile duct (CBD), the 2nd was without any communication with either CBD or its counterpart, thus remained as a blind vesicle.

8.
Bull Emerg Trauma ; 1(3): 127-9, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27162840

RESUMEN

Major pancreatic injury following blunt abdominal trauma by itself is a relatively rare occurrence, and in vast majority of cases (95%) it is associated with injury to adjacent major vessels and organs; thus making isolated major pancreatic injury even rarer. While most pancreatic injuries are managed by simple measures like debridement and drainage, complex proximal injury poses surgical challenge regarding surgical skill and judgement. Disproportionate approach at any stage of management can contribute  to high mortality and morbidity. Emergency pancreatoduodenectomy plays a limited but important role in managing serious trauma to proximal pancreas and duodenum. Author presents a case where isolated injury to head of pancreas required emergency pancreatoduodenectomy. After a bizarre road accident, a middle aged male underwent emergency laparotomy for intraperitoneal bleeding and during exploration a deep transverse laceration with ampullary disruption was found in the head of the organ. Duodenum in all its part was intact and there was no other injury. The nature and site of injury made emergency pancreatoduodenectomy the only viable option. Leaking pancreatojejunostomy enhances infective complications that lead to late mortality. To circumvent this problem there is enthusiasm for staged surgery with resection and tube pancreatostomy in first stage, leaving the difficult anastomosis for a later date, However, if the patient is haemodynamically stable and operated reasonably early, one stage pancreatoduodenectomy gives good result and avoids repeating surgery with inherent problems and reduces hospital stay. For successful management of pancreatic trauma it is essential to make early diagnosis of duct disruption, with sound application of operative skill and judgement by treating surgeon.

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