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1.
Water Sci Technol ; 84(9): 2406-2421, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34810320

RESUMO

This article focuses on the phycoremediation of pollutants from secondary treated coke-oven effluent through a green and economical route. A microalgal sample was collected and identified as a consortium of Chlorella sp. and Synechococcus sp. The culture cost was reduced by using poultry litter extract as supplementary material to BG-11 medium. Since the major pollutants present in real secondary treated coke-oven wastewater are phenol, ammoniacal-N (NH4+) and cyanide, several matrices were designed with these three major pollutants by varying their initial concentrations such as phenol (2-10 mg/L), cyanide (0.3-1 mg/L) and NH4+ (100-200 mg/L), termed as simulated secondary treated coke-oven wastewater. Maximum removal was observed with individual solutions of phenol (4 mg/L), cyanide (0.6 mg/L) and NH4+ (175 mg/L), while maximum removal in simulated secondary treated coke-oven wastewater was observed at higher concentrations of phenol (8 mg/L) and cyanide (0.8 mg/L) and the same concentration of NH4+ (175 mg/L). A consortium was found effective to meet statutory limits of pollutants. Kinetic model was developed for predicting growth of consortium and observed that the poultry litter extract-enriched BG-11 medium showed higher values of maximum specific growth rate (0.56 per day) and carrying capacity (1,330 mg/L) than that in BG-11 medium only.


Assuntos
Chlorella , Coque , Poluentes Ambientais , Animais , Coque/análise , Análise Custo-Benefício , Nutrientes , Aves Domésticas , Águas Residuárias/análise
2.
Environ Sci Pollut Res Int ; 28(15): 19285-19297, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33394392

RESUMO

Vapour-liquid equilibrium (VLE) of CO2 in aqueous dipropylenetriamine (DPTA) is investigated experimentally using a stirred equilibrium cell setup. Equilibrium solubility of CO2 is measured in the temperature and pressure range of (313-333) K and (1-100) kPa respectively. Composition of aqueous DPTA solvent used for the absorption study is in the range of (5-15) mass%. Experimental data shows higher CO2 loading capacity of this solvent compared to conventional solvents like monoethanolamine (MEA), 2-amino-2-methyl-1-propanol (AMP), and N-methyldiethanolamine (MDEA) as well as recently developed polyamine solvents like aminoethylethanolamine (AEEA), piperazine (PZ), and hexamethylenediamine (HMDA). Experimental VLE data is then correlated using the electrolyte non-random two-liquid (e-NRTL) theory which is an activity coefficient-based model for the electrolyte system. Data regression system (DRS) in Aspen Plus® (V8.8) is employed to fit the e-NRTL model equation with the experimental data by regressing the model parameters. Model-predicted data is found to be in good agreement with the experimental VLE data with an average absolute deviation of 22.3%. Performance of aqueous DPTA solvent is also analysed by predicting solvent capacity, equilibrium liquid-phase speciation, and heat of CO2 absorption using the newly developed e-NRTL model for the investigated system.


Assuntos
Dióxido de Carbono , Gases , Etanolamina , Temperatura , Água
3.
Saudi Pharm J ; 28(3): 325-328, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32194334

RESUMO

The amount of polysorbate 80 in pharmaceutical formulations affects the product quality and efficacy. A reliable test method is required to quantify the amount of Polysorbate 80 present in the drug product formulations. The test method for the determination of Polysorbate 80 may be used during process development and final product quality assessment. A simple, fast and efficient quantitative method, making use of HPLC-ELSD and a C18 column without sample pretreatment was developed. The developed method demonstrated specificity to polysorbate 80 with high precision as indicated by percent relative standard deviation (%RSD) of 3.0% for six determinations. The accuracy of this method for the determination of polysorbate 80 in a pharmaceutical formulation was demonstrated with an overall recovery of 94.9%.

4.
J Pharm Sci ; 108(10): 3187-3193, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31226425

RESUMO

Impurity investigations are important in pharmaceutical development to ensure drug purity and safety for the patient. The impurities typically found in drug products are degradants or reaction products of the active pharmaceutical ingredient (API) or leachable compounds from the container closure system. However, secondary reactions may also occur between API degradants, excipient impurities, residual solvents, and leachables to form adduct impurities. We hereby report an adduct-forming interaction of API (moxifloxacin) with a leachable compound (ethylene glycol monoformate) in moxifloxacin ophthalmic solution. The leachable compound originated from a low-density polyethylene bottle used in the packaging of drug products. The adduct impurity was tentatively identified as 1-cyclopropyl-6-fluoro-7-(1-(2-(formyloxy)ethyl) octahydro-6H-pyrrolo[3,4-b]pyridin-6-yl)-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (C24H28FN3O6, MW = 473.19621) using accurate mass LC-QTOF analysis. The mass accuracy error between the theoretical mass and the experimental mass of an impurity was found to be 0.2 ppm. An MS/MS analysis was utilized to provide mass spectrometry fragments to support verification of the proposed structure.


Assuntos
Contaminação de Medicamentos/prevenção & controle , Soluções Oftálmicas/química , Preparações Farmacêuticas/química , Cromatografia Líquida de Alta Pressão/métodos , Embalagem de Medicamentos/métodos , Espectrometria de Massas em Tandem/métodos
5.
J Gastrointest Cancer ; 48(4): 361-368, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27888389

RESUMO

PURPOSE: Gallstone is a high-risk factor for gallbladder pre-malignancy or malignancy (GB PM-M) but which substances of gallstones definitely assist to turn out in to GB PM-M, remains unclear. This study aimed to find out the presence of carcinogenic heavy metals in gallstones and to explore the aetiopathogenesis of gallbladder pre-malignancy and malignancy. METHODS: Presence of elements in gallstones was detected by energy dispersive X-ray spectroscopy (EDS) with scanning electron microscopy (SEM) and then level of carcinogenic heavy metals was estimated in gallstones using atomic absorption spectroscopy (AAS). The experiment was carried out in gallstone samples of 46 patients with gallbladder pre-malignant and malignant condition (PM-M group) and 65 sex and age-matched patients with chronic cholecystitis (C-C group). Gallstones were also classified in to three types such as cholesterol stone, mixed stone, and black pigment stone. RESULTS: EDS analysis detected presence of mercury, lead, and cobalt elements in all types of gallstones of both PM-M and C-C groups. AAS analysis revealed significantly higher amount of mercury (p < 0.001), lead (p < 0.0001), cobalt (p < 0.01), and cadmium (p < 0.01) in the gallstones of PM-M than C-C groups. The presence of these heavy metals also varied among stone types of both groups. EDS phase analysis showed 'dense deposits' of these metals in gallstones. CONCLUSIONS: Presence of significantly higher amount of mercury, lead, cobalt, and cadmium in gallstones may play a pivotal role as risk factors in the development of gallbladder malignancy or pre-malignancy. 'Dense deposits' of these metals in the gallstones which is the first observation, may act as crucial doses of carcinogens.


Assuntos
Neoplasias da Vesícula Biliar/etiologia , Metais Pesados/efeitos adversos , Adulto , Idoso , Feminino , Neoplasias da Vesícula Biliar/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
6.
Photochem Photobiol ; 92(1): 166-72, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26451683

RESUMO

We describe progress on a one-step photodynamic therapy (PDT) technique that is simple: device tip delivery of sensitizer, oxygen and light simultaneously. Control is essential for their delivery to target sites to generate singlet oxygen. One potential problem is the silica device tip may suffer from biomaterial fouling and the pace of sensitizer photorelease is slowed. Here, we have used biomaterial (e.g. proteins, cells, etc.) from SQ20B head and neck tumors and whole blood for an assessment of fouling of the silica tips by adsorption. It was shown that by exchanging the native silica tip for a fluorinated tip, a better nonstick property led to an increased sensitizer output by ~10%. The fluorinated tip gave a sigmoidal photorelease where singlet oxygen is stabilized to physical quenching, whereas the native silica tip with unprotected SiO-H groups gave a slower (pseudolinear) photorelease. A further benefit from fluorinated silica is that 15% less biomaterial adheres to its surface compared to native silica based on a bicinchoninic acid assay (BCA) and X-ray photoelectron spectroscopy (XPS) measurements. We discuss how the fluorination of the device tip increases biofouling resistance and can contribute to a new pointsource PDT tool.


Assuntos
Flúor/química , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Fotoquimioterapia/instrumentação , Materiais Biocompatíveis , Humanos
7.
ACS Appl Mater Interfaces ; 7(42): 23575-88, 2015 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-26372672

RESUMO

Condensation of water vapor is an essential process in power generation, water collection, and thermal management. Dropwise condensation, where condensed droplets are removed from the surface before coalescing into a film, has been shown to increase the heat transfer efficiency and water collection ability of many surfaces. Numerous efforts have been made to create surfaces which can promote dropwise condensation, including superhydrophobic surfaces on which water droplets are highly mobile. However, the challenge with using such surfaces in condensing environments is that hydrophobic coatings can degrade and/or water droplets on superhydrophobic surfaces transition from the mobile Cassie to the wetted Wenzel state over time and condensation shifts to a less-effective filmwise mechanism. To meet the need for a heat-transfer surface that can maintain stable dropwise condensation, we designed and fabricated a hybrid superhydrophobic-hydrophilic surface. An array of hydrophilic needles, thermally connected to a heat sink, was forced through a robust superhydrophobic polymer film. Condensation occurs preferentially on the needle surface due to differences in wettability and temperature. As the droplet grows, the liquid drop on the needle remains in the Cassie state and does not wet the underlying superhydrophobic surface. The water collection rate on this surface was studied using different surface tilt angles, needle array pitch values, and needle heights. Water condensation rates on the hybrid surface were shown to be 4 times greater than for a planar copper surface and twice as large for silanized silicon or superhydrophobic surfaces without hydrophilic features. A convection-conduction heat transfer model was developed; predicted water condensation rates were in good agreement with experimental observations. This type of hybrid superhydrophobic-hydrophilic surface with a larger array of needles is low-cost, robust, and scalable and so could be used for heat transfer and water collection applications.

8.
ACS Appl Mater Interfaces ; 5(18): 8915-24, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-23889192

RESUMO

Multifunctional superhydrophobic nanocomposite surfaces based on photocatalytic materials, such as fluorosilane modified TiO2, have generated significant research interest. However, there are two challenges to forming such multifunctional surfaces with stable superhydrophobic properties: the photocatalytic oxidation of the hydrophobic functional groups, which leads to the permanent loss of superhydrophobicity, as well as the photoinduced reversible hydrolysis of the catalytic particle surface. Herein, we report a simple and inexpensive template lamination method to fabricate multifunctional TiO2-high-density polyethylene (HDPE) nanocomposite surfaces exhibiting superhydrophobicity, UV-induced reversible wettability, and self-cleaning properties. The laminated surface possesses a hierarchical roughness spanning the micro- to nanoscale range. This was achieved by using a wire mesh template to emboss the HDPE surface creating an array of polymeric posts while partially embedding untreated TiO2 nanoparticles selectively into the top surface of these features. The surface exhibits excellent superhydrophobic properties immediately after lamination without any chemical surface modification to the TiO2 nanoparticles. Exposure to UV light causes the surface to become hydrophilic. This change in wettability can be reversed by heating the surface to restore superhydrophobicity. The effect of TiO2 nanoparticle surface coverage and chemical composition on the mechanism and magnitude of wettability changes was studied by EDX and XPS. In addition, the ability of the surface to shed impacting water droplets as well as the ability of such droplets to clean away particulate contaminants was demonstrated.


Assuntos
Nanocompostos/química , Polietilenos/química , Titânio/química , Raios Ultravioleta , Catálise , Interações Hidrofóbicas e Hidrofílicas , Oxirredução , Propriedades de Superfície , Molhabilidade
9.
Perspect Clin Res ; 3(1): 16-21, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22347697

RESUMO

OBJECTIVE: To compare the efficacy of up to 3 epidural butorphanol plus corticosteroid with corticosteroid alone for sciatica due to herniated nucleus pulposus. MATERIALS AND METHODS: In a randomized, double-blind controlled clinical trial, we administered up to 3 epidural injections of either 80 mg (2 mL) of methylprednisolone acetate and 1 mg (1 mL) of butorphanol diluted with 7 mL of isotonic saline or 80 mg (2 mL) of methylprednisolone acetate diluted with 8 mL of isotonic saline by a lumbar interlaminar approach under fluoroscopic guidance to 120 patients (60 patients in each group) with sciatica due to a herniated nucleus pulposus lasting for 4 weeks to 1 year. All patients had scores higher than 30 mm on visual analog scale (VAS). Information on the use of paracetamol, intensity of pain on a VAS ranging from 0 (no pain) to 100 mm (worst pain possible), Schober's test (cm), Straight Leg Raising test, neurologic examination assessing sensory deficits, motor deficits and reflex changes, and Oswestry Low Back Pain Disability Questionnaire were evaluated at 3 weeks, 6 weeks, and 3 months after the first injection. RESULTS: There were no significant differences between the 2 groups with regard to baseline characteristics, withdrawals, and complication rate. Three weeks, 6 weeks, and 3 months after the first injection, all the outcome measures in the butorphanol plus corticosteroid group were significantly different from that of the corticosteroid group. CONCLUSIONS: Epidural butorphanol plus corticosteroid injections, as compared with corticosteroid alone injections, offered marked improvement in pain, reflex, motor and sensory deficits, and functional status and reduced the need for analgesics. LEVEL OF EVIDENCE: Therapeutic Level I.

10.
Injury ; 43(7): 1066-70, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22333561

RESUMO

OBJECTIVE: To compare the safety, efficacy and reliability of FARES (fast, reliable and safe) method with the Eachempati external rotation method for reduction of anterior dislocation of shoulder. METHODS: In a single centre, prospective, randomised clinical trial, conducted in our institution from January 2010 to October 2011, 160 patients with acute anterior dislocation of shoulder (with or without an associated fracture of the greater tuberosity of the humerus) who satisfy the inclusion and exclusion criteria were enrolled in the study. Patients were randomised to receive reduction of dislocation with one of the two methods (FARES and Eachempati method) with 80 patients in each group, according to a table of random numbers. Following successful reduction, the following information was recorded: (i) intensity of pain perceived during reduction by using a visual analogue scale (VAS) ranging from 0 (no pain) to 100 (worst pain possible), (ii) time interval between the dislocation and the first attempt of reduction, (iii) time interval between the start of the reduction manoeuvre and completion of the reduction, (iv) number of attempts taken to complete the reduction and (iv) any post-reduction complications. RESULTS: There were no significant differences between the two groups with regard to baseline characteristics. No post-reduction complications were noted in any of the patients in this study. Successful reduction of shoulder dislocation was achieved with the FARES method in 76 (95%) of 80 patients and with the Eachempati external rotation method in 73 (91.25%) of 80 patients. This difference was not statistically significant (p=0.53, Fisher's exact test). Post-reduction result analysis shows that there was a statistically significant difference between the two methods in favour of the FARES method in terms of speed of reduction, pain felt during reduction and number of attempts taken during reduction. CONCLUSIONS: FARES method, as compared with the Eachempati method, is significantly faster, less painful and less number of attempts required for reduction. As both the methods appeared to be safe and effective compared to the previous traditional techniques, we strongly recommend FARES method as the first-choice method compared to Eachempati method for reduction of acute anterior dislocation of shoulder. LEVEL OF EVIDENCE: Therapeutic Level I.


Assuntos
Manipulação Ortopédica/métodos , Luxação do Ombro/terapia , Doença Aguda , Feminino , Humanos , Masculino , Manipulação Ortopédica/efeitos adversos , Dor/etiologia , Medição da Dor , Satisfação do Paciente/estatística & dados numéricos , Estudos Prospectivos , Reprodutibilidade dos Testes , Rotação , Luxação do Ombro/complicações , Luxação do Ombro/fisiopatologia , Resultado do Tratamento
11.
J Res Med Sci ; 17(8): 772-6, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23798945

RESUMO

BACKGROUND: Hemoglobinopathies are a group of inherited disorders of hemoglobin synthesis. It could be formed a fatal scenario in concern of lacking of actual information. Beside this, ABO and Rh blood grouping are also important matter in transfusion and forensic medicine and to reduce new born hemolytic disease (NHD). MATERIALS AND METHODS: The spectrum and prevalence of various hemoglobinopathies, ABO and rhesus (Rh) blood groups was screened among patients who visited B.S. Medical College and Hospital, Bankura, West Bengal, India. This study was carried out on 958 patients of different ages ranging from child to adults from January to June 2011. High-performance liquid chromatography (HPLC), complete blood count (CBC) and hemagglutination technique were performed for the assessment of abnormal hemoglobin variants, ABO and Rh blood groups, respectively. RESULTS: Results from this study had been shown that there was high prevalence of hemoglobinpathies (27.35%) where ß-thalassemia in heterozygous state occurred more frequent than other hemoglobinopathies. Out of 958 patients, 72.65% were HbAA and 27.35% were hemoglobinopathies individuals where 17.64% ß-thalassemia heterozygous, 2.92% ß-thalassemia homozygous, 3.86% HbAE, 1.15% HbAS trait, 1.25% HbE-ß thalassemia trait and 0.52% HbS-ß thalassemia trait were found. No incidence of HbSS, HbSC, HbCC, HbD and other variants of hemoglobinpathies were observed. The gene frequencies with respect to ABO systems had been shown as O > B > A > AB. Blood group O was the highest (35.8%) and the least percentage distribution was blood group AB (6.68%). Rhesus positive (Rh+) were 97.7%, while the remaining was 2.3% Rhesus negative (Rh-). The frequencies of A(+), B(+), AB(+,) and O(+) blood groups were 22.44%, 33.61%, 6.58%, and 35.07%, respectively. CONCLUSIONS: Remarkable percentages of hemoglobinopathies were prevalent from the present study. An extensive screening of the population is needed to assess the prevalence of hemoglobinopathies, which will help in identification of carriers of hemoglobinopathies and further it will be of assistance in taking adequate therapeutic and preventive measures.

12.
ACS Appl Mater Interfaces ; 3(9): 3508-14, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21797228

RESUMO

Fabricating robust superhydrophobic surfaces for commercial applications is challenging as the fine-scale surface features, necessary to achieve superhydrophobicity, are susceptible to mechanical damage. Herein, we report a simple and inexpensive lamination templating method to create superhydrophobic polymer surfaces with excellent abrasion resistance and water pressure stability. To fabricate the surfaces, polyethylene films were laminated against woven wire mesh templates. After cooling, the mesh was peeled from the polymer creating a 3D array of ordered polymer microposts on the polymer surface. The resulting texture is monolithic with the polymer film and requires no chemical modification to exhibit superhydrophobicity. By controlling lamination parameters and mesh dimensions, polyethylene surfaces were fabricated that exhibit static contact angles of 160° and slip angles of 5°. Chemical and mechanical stability was evaluated using an array of manual tests as well as a standard reciprocating abraser test. Surfaces remained superhydrophobic after more than 5500 abrasion cycles at a pressure of 32.0 kPa. In addition, the surface remains dry after immersing into water for 5 h at 55 kPa. This method is environmental friendly, as it employs no solvents or harsh chemicals and may provide an economically viable path to manufacture large areas of mechanically robust superhydrophobic surfaces from inexpensive polymers and reusable templates.


Assuntos
Polímeros/química , Interações Hidrofóbicas e Hidrofílicas , Polietileno/química , Pressão , Propriedades de Superfície , Água/química
13.
Methods Mol Biol ; 751: 29-42, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21674323

RESUMO

We present here a general methodology for significantly increasing the number of dye/drug molecules that can be attached per protein molecule. As a demonstration of this approach, poly(acrylic acid) (PAA)-based near-infrared fluorescence (NIRF) dye- and glucose-incorporated novel copolymers were synthesized, which were further employed for bioconjugation to avidin and bovine serum albumin (BSA). In this method, azide-terminated poly(tert-butyl acrylate) was synthesized via atom transfer radical polymerization (ATRP). Subsequent deprotection was performed to yield poly(acrylic acid) (PAA) possessing a reactive chain-end. A one-pot sequential amidation of the PAA with the amine derivatives of a near-infrared fluorescent dye (ADS832WS) and glucose produced NIRF dye-incorporated water-soluble copolymers. End-group modifications were performed to produce alkyne/biotin-terminated copolymers, which were further employed to generate dye-incorporated polymer-protein hybrids via the biotin-avidin interaction with avidin or by "click" bioconjugation with azide-modified BSA.


Assuntos
Corantes Fluorescentes/química , Polímeros/química , Proteínas/química , Alcinos/química , Aminas/química , Animais , Avidina/química , Biotina/química , Bovinos , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Glucosamina/química , Ácido Poliglutâmico/química , Soroalbumina Bovina/química
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