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2.
OMICS ; 23(6): 318-326, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31120389

RESUMEN

Elizabethkingia meningoseptica is Gram-negative, rod-shaped opportunistic bacterial pathogen increasingly reported in hospital-acquired outbreaks. This bacterium is well known to thrive in the hospital environment. One of the leading causes of meningitis in pediatric and immune-compromised patients, E. meningoseptica has been noted as a "pathogen of interest" in the context of nosocomial diseases associated with device-related infections in particular. This pathogen's multidrug-resistant phenotype and attendant lack of adequate molecular mechanistic data limit the current approaches for its effective management in hospitals and public health settings. This study provides the global proteome of E. meningoseptica. The reference strain E. meningoseptica ATCC 13253 was used for proteomic analysis using high-resolution Fourier transform mass spectrometry. The study provided translational evidence for 2506 proteins of E. meningoseptica. We identified multiple metallo-ß-lactamases, transcriptional regulators, and efflux transporter proteins associated with multidrug resistance. A protein Car D, which is an enzyme of the carbapenem synthesis pathway, was also discovered in E. meningoseptica. Further, the proteomics data were harnessed for refining the genome annotation. We discovered 39 novel protein-coding genes and corrected four existing translations using proteogenomic workflow. Novel translations reported in this study enhance the molecular data on this organism, thus improving current databases. We believe that the in-depth proteomic data presented in this study offer a platform for accelerated research on this pathogen. The identification of multiple proteins, particularly those involved in drug resistance, offers new future opportunities to design novel and specific antibiotics against infections caused by E. meningoseptica.


Asunto(s)
Chryseobacterium/efectos de los fármacos , Chryseobacterium/metabolismo , Enfermedades Transmisibles/metabolismo , Proteómica/métodos , Antibacterianos/farmacología , Humanos , Pruebas de Sensibilidad Microbiana
3.
Trop Doct ; 49(3): 230-232, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30895884

RESUMEN

Osteopetrosis is a rare congenital disease presenting with recurrent fractures, hematopoietic insufficiency and hepatosplenomegaly. Though osteomyelitis is a known complication in osteopetrosis, osteopetrosis presenting as osteomyelitis is rare. Management consists of multidisciplinary approach for complications and bone marrow transplant for the infantile form of disease.


Asunto(s)
Osteomielitis/etiología , Osteopetrosis/diagnóstico por imagen , Niño , Humanos , Masculino , Osteopetrosis/complicaciones , Radiografía
5.
J Environ Manage ; 125: 68-73, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23644591

RESUMEN

Recovery of valuable materials/metals from waste goes hand in hand with environmental protection. This paper deals with the development of a process for the recovery of metals such as Mo, V, Ni, Al from spent hydroprocessing catalyst which may otherwise cause a nuisance if dumped untreated. A detailed study on the separation of molybdenum and vanadium from the leach solution of spent hydroprocessing catalyst of composition: 27.15% MoO3, 1.7% V2O5, 3.75% NiO, 54.3% Al2O3, 2.3% SiO2 and 10.4% LOI is reported in this paper. The catalyst was subjected to roasting under oxidizing atmosphere at a temperature of about 550 °C and leaching in dilute sulphuric acid to dissolve molybdenum, vanadium, nickel and part of aluminium. Metals from the leach solution were separated by solvent extraction. Both molybdenum and vanadium were selectively extracted with a suitable organic solvent leaving nickel and dissolved aluminium in the raffinate. Various parameters such as initial pH of the aqueous feed, organic to aqueous ratio (O:A), solvent concentration etc. were optimized for the complete extraction and recovery of Mo and V. Molybdenum and vanadium from the loaded organic were stripped by ammonia solution. They were recovered as their corresponding ammonium salt by selective precipitation, and were further calcined to get the corresponding oxides in pure form.


Asunto(s)
Residuos Peligrosos , Molibdeno/química , Vanadio/química , Aluminio/química , Catálisis , Níquel/química , Solventes/química
6.
J Environ Manage ; 92(12): 3105-11, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21862202

RESUMEN

Solvent extraction of iron(III) from actual sulphate waste pickle liquor was investigated using trialkylphosphine oxide diluted with kerosene. The waste pickle liquor was procured from a local company which deals with the manufacturing of pipes and tubes made of iron and steel. Various parameters were studied to optimise a suitable condition for the maximum extraction of iron. The composition of the aqueous feed used in the experiment was 60.88 g/L Fe(III), 53 g/L acid with traces of Cu, Ni and Co. An ambient extraction at 30 °C yielded acceptable kinetics and loading efficiency for 40% trialkylphosphine oxide with a saturated loading capacity of 51.85 g/L in four contacts at O/A ratio of 1/1 in a multiple contact mode. Iron from the loaded organic was stripped using various strippants such as distilled water, H(2)SO(4) and oxalic acid. Since only 32% of loaded Fe could be stripped with 2 M H(2)SO(4) in five contacts, further stripping was done with 5% oxalic acid which showed a very promising result. It was found that almost 100% of Fe(III) could be stripped out with 5% oxalic acid at O/A of 1/1 in five contacts.


Asunto(s)
Hierro/química , Sulfatos/química , Administración de Residuos/métodos , Residuos Industriales , Hierro/análisis , Cinética , Solventes/química , Acero
7.
Pharm Methods ; 2(3): 184-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23781453

RESUMEN

BACKGROUND: Hydrotropic solubilization process involves cooperative intermolecular interaction with several balancing molecular forces, rather than either a specific complexation event or a process dominated by a medium effect, such as co-solvency or salting-in. MATERIALS AND METHODS: In the present investigation, hydrotropic solution of 2 M niacinamide was employed as the solubilizing agent to solubilize the poorly water-soluble drug, indomethacin, from the capsule dosage form for spectrophotometric determination in ultraviolet region. RESULTS: Hydrotropic agent used did not interfere in the spectrophotometric analysis. In preliminary solubility studies, it was found that there was more than fivefold enhancement in the aqueous solubility of indomethacin (poorly water-soluble drug) in 2 M niacinamide solution as compared to its aqueous solubility at 28 ± 1°C. CONCLUSION: The proposed method is new, simple, safe, environmentally friendly, economic, accurate and cost-effective and can be successfully employed in routine analysis.

8.
J Hazard Mater ; 171(1-3): 61-75, 2009 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-19632040

RESUMEN

Every metal and metallurgical industry is associated with the generation of waste, which may be a solid, liquid or gaseous in nature. Their impacts on the ecological bodies are noticeable due to their complex and hazardous nature affecting the living and non-living environment which is an alarming issue to the environmentalist. The increasingly stringent regulations regarding the discharge of acid and metal into the environment, and the increasing stress upon the recycling/reuse of these effluents after proper treatment have focused the interest of the research community on the development of new approaches for the recovery of acid and metals from industrial wastes. This paper is a critical review on the acidic waste streams generated from steel and electroplating industries particularly from waste pickle liquor and spent bleed streams. Various aspects on the generation of these streams and the methods used for their treatment either for the recovery of acid for reuse or disposal are being dealt with. Major stress is laid upon the hydrometallurgical methods such as solvent extraction.


Asunto(s)
Ácidos/aislamiento & purificación , Galvanoplastia/instrumentación , Galvanoplastia/métodos , Residuos Industriales , Contaminantes Químicos del Agua/aislamiento & purificación , Ácidos/química , Cromatografía por Intercambio Iónico/métodos , Cobre/química , Electrólisis , Ácido Clorhídrico/análisis , Hidrólisis , Metales/química , Oxidación-Reducción , Solventes/química , Ácidos Sulfúricos/análisis , Purificación del Agua , Zinc/química
9.
J Hazard Mater ; 159(2-3): 458-64, 2008 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-18417285

RESUMEN

Extractive removal of Cr (VI) was carried out from chloride solutions using cyanex 923 mixed with kerosene. The efficiency of this extractant was studied under various experimental conditions, such as concentration of different mineral acids in the aqueous phase, concentration of cyanex 923 and Cr (VI) present in the initial aqueous feed, temperature and time of extraction, organic to aqueous (O/A) phase ratio. Percentage Cr (VI) extraction decreases with the increase in temperature at varying concentration of cyanex 923. The interference of the impurities usually associated with Cr (VI) such as Cr (III), Cu, Ni, Fe (II), Zn, Chloride and sulphate, etc., were examined under the optimized conditions and only Zn was found to interfere. Under the optimum experimental conditions 98.6-99.9% of Cr (VI) was extracted in 3-5 min at O/A of 2 with the initial feed concentration of 1g/L of Cr (VI). The extracted Cr (VI) was quantitatively stripped with 1M NaOH and the organic phase obtained after the stripping of Cr (VI) was washed with dilute HCl solution to neutralize any NaOH trapped/adhered to the solvent and then with distilled water. This regenerated solvent was reused in succeeding extraction of chromium (VI). Finally a few experiments were performed with the synthetic effluent from an electroplating industry.


Asunto(s)
Cromo/aislamiento & purificación , Residuos Industriales/análisis , Contaminantes Químicos del Agua/análisis , Ácidos/química , Concentración de Iones de Hidrógeno , Indicadores y Reactivos , Hidróxido de Sodio , Soluciones , Solventes , Temperatura
10.
J Hazard Mater ; 137(2): 915-24, 2006 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-16716498

RESUMEN

The adsorption equilibrium and kinetics studies of cadmium (Cd) ions from aqueous solutions on manganese nodule residue were carried out by considering the influence of various parameters, such as contact time, solution pH and initial metal concentration in solution, temperature and adsorbent quantity. The adsorption of Cd increased with an increase in the concentrations of this metal in solution. Presence of manganese and iron content in manganese nodule residue (MNR) played a significant role in Cd(II) ions removal. The linear forms of the Langmuir and Freundlich equations were utilized for experiments with metal concentrations of 200 mg/L for Cd(II) as functions of solution pH (2.0-6.0). First-order rate equation and pseudo second-order rate equations were applied to study adsorption kinetics. Mass transfer study was also done to know the reaction rate. Thermodynamic parameters, such as standard Gibb's free energy (deltaG(o)), standard enthalpy (deltaH(o)) and standard entropy (deltaS(o)), were also evaluated by Van't Hoff equation. Thus, adsorption of Cd on this adsorbent was found to be spontaneous and exothermic thermodynamically. The adsorption capacity for Cd was found to be 19.8 mg/g of MNR. Under the optimised conditions, cadmium level was brought down from 100 mg/L to Cd less than detection limits and from 200 to 2 mg/L. Thus, the wastewater after cadmium removal could be safely disposed off on to land or sewage. Finally, the metal loaded adsorbent was subjected to desorption using different mineral acids and leaching by using toxicity characteristic leaching procedure (TCLP), synthetic precipitation leaching procedure (SPLP) tests for its further treatment or its safe disposal.


Asunto(s)
Cadmio/farmacocinética , Contaminantes Ambientales/farmacocinética , Manganeso , Termodinámica , Adsorción , Cinética
11.
J Hazard Mater ; 133(1-3): 299-303, 2006 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-16621270

RESUMEN

A weakly acidic ion exchanger resin containing the iminodiacetate group has been used to separate and recover metal ion from their mixtures. Batch and column methods were applied for the separation studies. Previous study on the kinetics and thermodynamics shows that the selectivity of this resin for transition metals was quite high as compared to that of alkaline earth metals. The efficiency of this resin in different experimental conditions was established and because of the large difference in the distribution coefficient values separation of the metal ions from their mixture was performed.


Asunto(s)
Quelantes/química , Resinas de Intercambio Iónico/química , Plomo/química , Plomo/aislamiento & purificación , Resinas Sintéticas/química , Aleaciones/síntesis química , Aleaciones/química , Cromatografía por Intercambio Iónico , Concentración de Iones de Hidrógeno
12.
Waste Manag Res ; 24(1): 74-9, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16496873

RESUMEN

To recover pigment grade TiO2, operating plants all over the world use chemical processes. Slag-based technology is considered to be attractive because of low waste generation and low chemical cost due to high titanium content and is poised to replace the conventional technology. This paper provides a review of the slag-based technology with the specific aim to produce leachable slag and achieving high titania yield from recovered wastes. Leachable oxides of the lower oxidation state, such as TiO and Ti2O3, facilitate the leaching process. However, during smelting these oxides increase the viscosity of the slag. Formation of titanium carbide or carbonitride is also not desirable as it leads to resistance to the leaching of titanium. This report highlights the problems and their possible solutions to obtain leachable slag.


Asunto(s)
Conservación de los Recursos Naturales , Residuos Industriales , Titanio/aislamiento & purificación , Cloro/química , Metalurgia , Ácidos Sulfúricos/química , Titanio/química
13.
J Colloid Interface Sci ; 281(2): 291-8, 2005 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-15571684

RESUMEN

Lead adsorption from aqueous solutions was studied with the aim of detoxifying industrial effluents before their safe disposal onto land or into river waters. Sea nodule residue (SNR), a waste material containing oxides and oxyhydroxides of manganese, iron, silicon, etc., was used as an effective adsorbent for lead in this study. The effect of various parameters such as contact time, initial lead concentration, pulp density, particle size of the adsorbent, pH, and temperature was studied to optimize the conditions for maximum adsorption. Adsorption followed first-order kinetics and 99% of lead adsorption was achieved at a solid:liquid ratio of 1:330, in the pH range 5.5-6.0 at a particle size of -150 microm in 8 h for solution containing 200 ppm lead. The adsorption capacity was found to be 99.0 mg of lead per gram of SNR and the adsorption isotherms followed the Langmuir and Freundlich adsorption models. The mechanism of adsorption of lead onto the sea nodule residue was also investigated. It was possible to reduce the lead level from 25-200 ppm to acceptable levels (0.1 ppm) by adsorption over this solid waste.

14.
Waste Manag Res ; 22(4): 240-7, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15462331

RESUMEN

Implementation of stricter environmental laws and economic reasons has forced all the metallurgical industries to go for eco-friendly technologies to produce metal and other related products. However, generation of wastes is an integral part of metallurgical industries. If the wastes/residues are hazardous in nature, they generally have to be treated or/and disposed of in safe and designated dumping sites. If these wastes/residues are non-hazardous in nature, then they may be suitable for use as secondary raw material to recover metals such as lead, copper etc., which are in growing demand all over the world. The processing of lead secondaries is important because of their relative high metal content, as well as the low energy and cost involved in recovering the metal. This paper mainly focuses on the current practices and recent trends in the secondary processing of lead. Various processes, particularly hydrometallurgical ones, already developed or in the development stages, are discussed. Attempts made by various Council of Scientific and Industrial Research (CSIR) Laboratories including the National Metallurgical Laboratory (NML) and industries such as Binani Zinc to develop eco-friendly processes for the recovery of lead from secondary raw materials are also described.


Asunto(s)
Plomo/aislamiento & purificación , Metalurgia , Eliminación de Residuos/métodos , Conservación de los Recursos Naturales , Contaminación Ambiental , Residuos Industriales
15.
Waste Manag Res ; 22(4): 248-54, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15462332

RESUMEN

Almost all metallurgical processes are associated with the generation of wastes and residues that may be hazardous or non-hazardous in nature depending upon the criteria specified by institutions such as the US Environment Protection Agency, etc. Wastes containing heavy and toxic metals such as arsenic, cadmium, chromium, nickel, lead, copper, mercury, zinc, etc., that are present beyond permissible limits deemed to be treated or disposed of, and non-hazardous wastes can be utilized for metal recovery or safe disposal. Zinc is in growing demand all over the world. In India, a major amount of zinc is imported and therefore processing of zinc secondaries will assist in satisfying the gap between demand and supply to some extent. This report mainly focuses on the current practices and recent trends on the secondary processing of zinc. Attempts made by various laboratories to develop ecofriendly processes for the recovery of zinc from secondary raw materials are also described and discussed.


Asunto(s)
Contaminación Ambiental/prevención & control , Metalurgia , Eliminación de Residuos/métodos , Zinc/aislamiento & purificación , Conservación de los Recursos Naturales , India , Residuos Industriales , Eliminación de Residuos/economía
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