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Pandey M, Xess I, Sachdev J, Sharad N, Gupta S, Singh G, Yadav RK, Rana B, Raj S, Ahmad MN, Nityadarshini N, Baitha U, Soneja M, Shalimar, Prakash B, Sikka K, Mathur P, Jyotsna VP, Kumar R, Wig N, Gourav S, Biswas A, Thakar A. Utility of an in-house real-time PCR in whole blood samples as a minimally invasive method for early and accurate diagnosis of invasive mould infections. J Infect 2024; 88:106147. [PMID: 38555035 DOI: 10.1016/j.jinf.2024.106147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 03/11/2024] [Accepted: 03/24/2024] [Indexed: 04/02/2024]
Abstract
INTRODUCTION Invasive mould infections (IMIs) are a leading cause of death in patients with compromised immune systems. Proven invasive mould infection requires detection of a fungus by histopathological analysis of a biopsied specimen, sterile culture, or fungal DNA amplification by PCR in tissue. However, the clinical performance of a PCR assay on blood samples taken from patients suspected of invasive mould disease has not been fully evaluated, particularly for the differential diagnosis of invasive aspergillosis (IA) and invasive Mucormycosis (IM). OBJECTIVES To assess the diagnostic utility of our previously validated in-house real-time PCR in blood samples for diagnosis of invasive aspergillosis and mucormycosis in patients with suspected invasive mould infection. METHODS All patients with suspected invasive mould infection were prospectively enrolled from May 2021 to July 2021. Conventional fungal diagnosis was performed using tissue and respiratory samples. In-house PCR was performed on blood samples and its diagnostic performance evaluated. RESULTS A total of 158 cases of suspected invasive mould infection were enrolled in the study. The sensitivity and specificity of in-house PCR performed on blood samples was found to be 92.5% and 81.4% respectively for diagnosis of probable IA, and 65% and 84.62% respectively for diagnosis of proven and probable IM. It was also able to detect 3 out of 5 cases of possible IM where no other microbiological evidence of IM was obtained. CONCLUSIONS This assay could be helpful in minimally invasive diagnosis of IMIs for patients in whom invasive sampling is not feasible, especially as a preliminary or screening test. It can help in early diagnosis, anticipating conventional laboratory confirmation by days or weeks. Possible correlation between fungal load and mortality can help in initiating aggressive treatment for patients with high initial fungal load.
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Affiliation(s)
- Mragnayani Pandey
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Immaculata Xess
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India.
| | - Janya Sachdev
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Neha Sharad
- Department of Lab medicine JPNATC, All India Institute of Medical Sciences, New Delhi, India
| | - Sonakshi Gupta
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Gagandeep Singh
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Renu Kumari Yadav
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Bhaskar Rana
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Stephen Raj
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - M Nizam Ahmad
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Neha Nityadarshini
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Upendra Baitha
- Department of Medicine, All India Institute of Medical Sciences, New Delhi, India
| | - Manish Soneja
- Department of Medicine, All India Institute of Medical Sciences, New Delhi, India
| | - Shalimar
- Department of Gastroenterology, All India Institute of Medical Sciences, New Delhi, India
| | - Bindu Prakash
- Department of Medicine, All India Institute of Medical Sciences, New Delhi, India
| | - Kapil Sikka
- Department of ENT, All India Institute of Medical Sciences, New Delhi, India
| | - Purva Mathur
- Department of Lab medicine JPNATC, All India Institute of Medical Sciences, New Delhi, India
| | - Viveka P Jyotsna
- Department of Endocrinology, All India Institute of Medical Sciences, New Delhi, India
| | - Rakesh Kumar
- Department of ENT, All India Institute of Medical Sciences, New Delhi, India
| | - Naveet Wig
- Department of Medicine, All India Institute of Medical Sciences, New Delhi, India
| | - Sudesh Gourav
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Ashutosh Biswas
- Department of Medicine, All India Institute of Medical Sciences, New Delhi, India
| | - Alok Thakar
- Department of ENT, All India Institute of Medical Sciences, New Delhi, India
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Tan KH, Iqbal A, Adam F, Abu Bakar NHH, Ahmad MN, Yusop RM, Pauzi H. Influence of Mg/CTAB ratio on the structural, physicochemical properties and catalytic activity of amorphous mesoporous magnesium silicate catalysts. RSC Adv 2019; 9:38760-38771. [PMID: 35540239 PMCID: PMC9075996 DOI: 10.1039/c9ra08024d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 11/18/2019] [Indexed: 11/24/2022] Open
Abstract
This study investigated the physicochemical and catalytic properties of mesoporous magnesium silicate catalysts prepared at various Mg/CTAB ratios (0.25, 0.50, 0.75 and 1.00). The XPS analysis detected a mixture of enstatite and magnesium carbonate species when the Mg/CTAB ratio was 0.25, and 0.50. A mixture of forsterite and magnesium carbonate species were detected when the Mg/CTAB ratio was 0.75 whereas for the Mg/CTAB ratio of 1.00, enstatite and magnesium metasilicate species were detected. A catalyst with the Mg/CTAB ratio of 1.00 demonstrated the highest catalytic activity in the oxidation of styrene. The styrene conversion rate was 59.0%, with 69.2% styrene oxide (StO) selectivity. The H2O2 molecules were activated regio-specifically by the magnesium species to prevent rapid self-decomposition while promoting selective interaction with styrene. All the parameters that influence the styrene conversion and product selectivity were evaluated using analysis of variance (ANOVA) with Tukey's test. The ANOVA analysis showed that the reaction time (h), Mg/CTAB ratio, styrene/H2O2 ratio, catalyst loading (mg) and temperature (°C) affect styrene conversion and product selectivity (StO) significantly (p < 0.05). The oxidation of styrene was well fitted to the pseudo-first-order model. The activation energy, Ea of the catalysed styrene epoxidation reaction was calculated to be 27.7 kJmol−1. The catalyst can be reused several times without any significant loss in its activity and selectivity. The results from this study will be useful in designing and developing low cost, high activity catalysts from alkaline earth metals. Increasing the magnesium content in direct synthesis will lead to the formation of different magnesium active sites that increase the styrene oxide selectivity under the same reaction conditions.![]()
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Affiliation(s)
- Kok-Hou Tan
- School of Chemical Sciences, Universiti Sains Malaysia 11800 Penang Malaysia +604-6533565
| | - Anwar Iqbal
- School of Chemical Sciences, Universiti Sains Malaysia 11800 Penang Malaysia +604-6533565.,School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia 43600 UKM, Bangi Malaysia
| | - Farook Adam
- School of Chemical Sciences, Universiti Sains Malaysia 11800 Penang Malaysia +604-6533565
| | - N H H Abu Bakar
- School of Chemical Sciences, Universiti Sains Malaysia 11800 Penang Malaysia +604-6533565
| | - M N Ahmad
- Experimental and Theoretical Research Lab, Department of Chemistry, Kulliyyah of Science, International Islamic University Malaysia Bandar Indera Mahkota 25200 Kuantan Pahang Malaysia
| | - Rahimi M Yusop
- School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia 43600 UKM, Bangi Malaysia
| | - Hariy Pauzi
- Science and Engineering Research Centre (SERC), Universiti Sains Malaysia Engineering Campus, 14300 Nibong Tebal Seberang Perai Selatan Penang Malaysia
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Hancock BA, Chen YH, Solzak JP, Ahmad MN, Wedge DC, Brinza D, Scafe C, Veitch J, Gottimukkala R, Short W, Atale RV, Ivan M, Badve SS, Schneider BP, Miller KD, Radovich M. Abstract P2-07-04: Molecular regulators of resistance and relapse in chemorefractory triple-negative breast cancers. Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-p2-07-04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Triple-Negative Breast Cancer (TNBC) accounts for approximately one-fifth of breast cancer incidence but disproportionately high mortality. Two-thirds of early-stage TNBCs are resistant to pre-surgical chemotherapy and highly prone to relapse within 3 years. Morever, no advanced therapies are indicated for patients with these cancers. We have embarked on a comprehensive genomic analysis of chemoresistant TNBC to gain an in-depth understanding of molecular entities driving chemoresistance and relapse. By collecting somatic mutation and copy number, RNA-sequencing, and outcome data in the context of a phase II post-neoadjuvant clinical trial, we have uncovered several molecular mechanisms behind these aggressive cancers. Through the analysis of matched pairs sampled before and after chemotherapy, we have discovered multiple means by which tumors are able to overcome the effects of chemotherapy including clonal evolution of high-level oncogene amplification, repression of the in situ immune system, and upregulation of the stem cell-related MEK-ERK and JAK-STAT pathways. Investigation into factors related to prognosis revealed important correlations between relapse and immune and JAK-STAT signaling. Finally, using a novel method of demarcating loss-of-function of p53, which we have termed graduated inactivation, we discovered additional associations between p53 loss and relapse, mortality, and MYC signalling.
Citation Format: Hancock BA, Chen Y-H, Solzak JP, Ahmad MN, Wedge DC, Brinza D, Scafe C, Veitch J, Gottimukkala R, Short W, Atale RV, Ivan M, Badve SS, Schneider BP, Miller KD, Radovich M. Molecular regulators of resistance and relapse in chemorefractory triple-negative breast cancers [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-07-04.
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Affiliation(s)
- BA Hancock
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - Y-H Chen
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - JP Solzak
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - MN Ahmad
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - DC Wedge
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - D Brinza
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - C Scafe
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - J Veitch
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - R Gottimukkala
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - W Short
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - RV Atale
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - M Ivan
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - SS Badve
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - BP Schneider
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - KD Miller
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
| | - M Radovich
- Indiana University School of Medicine, Indianapolis, IN; Oxford University, Oxford, United Kingdom; ThermoFisher Scientific, Carlsbad, CA
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Mohiuddin M, Arbain D, Islam AKMS, Ahmad MS, Ahmad MN. Alpha-Glucosidase Enzyme Biosensor for the Electrochemical Measurement of Antidiabetic Potential of Medicinal Plants. Nanoscale Res Lett 2016; 11:95. [PMID: 26887579 PMCID: PMC4759339 DOI: 10.1186/s11671-016-1292-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 02/01/2016] [Indexed: 06/05/2023]
Abstract
A biosensor for measuring the antidiabetic potential of medicinal plants was developed by covalent immobilization of α-glucosidase (AG) enzyme onto amine-functionalized multi-walled carbon nanotubes (MWCNTs-NH2). The immobilized enzyme was entrapped in freeze-thawed polyvinyl alcohol (PVA) together with p-nitrophenyl-α-D-glucopyranoside (PNPG) on the screen-printed carbon electrode at low pH to prevent the premature reaction between PNPG and AG enzyme. The enzymatic reaction within the biosensor is inhibited by bioactive compounds in the medicinal plant extracts. The capability of medicinal plants to inhibit the AG enzyme on the electrode correlates to the potential of the medicinal plants to inhibit the production of glucose from the carbohydrate in the human body. Thus, the inhibition indicates the antidiabetic potential of the medicinal plants. The performance of the biosensor was evaluated to measure the antidiabetic potential of three medicinal plants such as Tebengau (Ehretis laevis), Cemumar (Micromelum pubescens), and Kedondong (Spondias dulcis) and acarbose (commercial antidiabetic drug) via cyclic voltammetry, amperometry, and spectrophotometry. The cyclic voltammetry (CV) response for the inhibition of the AG enzyme activity by Tebengau plant extracts showed a linear relation in the range from 0.423-8.29 μA, and the inhibition detection limit was 0.253 μA. The biosensor exhibited good sensitivity (0.422 μA/mg Tebengau plant extracts) and rapid response (22 s). The biosensor retains approximately 82.16 % of its initial activity even after 30 days of storage at 4 °C.
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Affiliation(s)
- M Mohiuddin
- Production Department, Palash Urea Fertilizer Factory Ltd., Bangladesh Chemical Industries Corporation, Dhaka, Bangladesh.
| | - D Arbain
- School of Bioprocess Engineering, Universiti Malaysia Perlis, 01000, Kangar, Perlis, Malaysia
| | - A K M Shafiqul Islam
- School of Bioprocess Engineering, Universiti Malaysia Perlis, 01000, Kangar, Perlis, Malaysia
- Centre of Excellence for Advanced Sensor Technology, Universiti Malaysia Perlis, 01000, Kangar, Perlis, Malaysia
| | - M S Ahmad
- School of Bioprocess Engineering, Universiti Malaysia Perlis, 01000, Kangar, Perlis, Malaysia
| | - M N Ahmad
- Centre of Excellence for Advanced Sensor Technology, Universiti Malaysia Perlis, 01000, Kangar, Perlis, Malaysia
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Chong HLH, Chia PS, Ahmad MN. The adsorption of heavy metal by Bornean oil palm shell and its potential application as constructed wetland media. Bioresour Technol 2013; 130:181-186. [PMID: 23306127 DOI: 10.1016/j.biortech.2012.11.136] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Revised: 11/24/2012] [Accepted: 11/28/2012] [Indexed: 06/01/2023]
Abstract
Oil palm shell, a waste from palm oil industry, was cleaned and utilized as adsorbent. Its particle size distribution gave the uniformity coefficient of approximately two indicating that it can be used as filter bed media for continuous operation without resting. Its measured pH(pzc) of 4.1 is below the common pH of constructed wetland water body suggesting positive adsorption for heavy metal. The effect of various parameters on its adsorption was studied via batch experiments. The adsorption of Cu(II) and Pb(II) ions by oil palm shell showed a slightly better fit with the Freundlich compared to Langmuir. Its monolayer adsorption capacities were found to be 1.756 and 3.390mg/g for Cu(II) and Pb(II), respectively. High correlation coefficient of over 0.99 given by the pseudo-second-order model suggests that the rate limiting factor may be chemisorption. These findings suggest its potential application as constructed wetland media for the removal of heavy metal.
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Affiliation(s)
- H L H Chong
- Water Research Unit, School of Science and Technology, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia.
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Al-Degs YS, Khraisheh MAM, Allen SJ, Ahmad MN. Adsorption characteristics of reactive dyes in columns of activated carbon. J Hazard Mater 2009; 165:944-949. [PMID: 19056173 DOI: 10.1016/j.jhazmat.2008.10.081] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Revised: 10/19/2008] [Accepted: 10/22/2008] [Indexed: 05/27/2023]
Abstract
Adsorption behaviour of reactive dyes in fixed-bed adsorber was evaluated in this work. The characteristics of mass transfer zone (MTZ), where adsorption in column occurs, were affected by carbon bed depth and influent dye concentration. The working lifetime (t(x)) of MTZ, the height of mass transfer zone (HMTZ), the rate of mass transfer zone (RMTZ), and the column capacity at exhaustion (q(column)) were estimated for the removal of remazol reactive yellow and remazol reactive black by carbon adsorber. The results showed that column capacity calculated at 90% of column exhaustion was lower than carbon capacity obtained from equilibrium studies. This indicated that the capacity of activated carbon was not fully utilized in the fixed-bed adsorber. The bed-depth service time model (BDST) was applied for analysis of reactive yellow adsorption in the column. The adsorption capacity of reactive yellow calculated at 50% breakthrough point (N(0)) was found to be 0.1 kg kg(-1) and this value is equivalent to about 14% of the available carbon capacity. The results of this study indicated the applicability of fixed-bed adsorber for removing remazol reactive yellow from solution.
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Affiliation(s)
- Y S Al-Degs
- Chemistry Department, The Hashemite University, Zarqa, Jordan.
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Al-Ghouti MA, Khraisheh MAM, Ahmad MN, Allen SJ. Microcolumn studies of dye adsorption onto manganese oxides modified diatomite. J Hazard Mater 2007; 146:316-27. [PMID: 17222966 DOI: 10.1016/j.jhazmat.2006.12.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2006] [Revised: 12/10/2006] [Accepted: 12/12/2006] [Indexed: 05/13/2023]
Abstract
The method described here cannot fully replace the analysis of large columns by small test columns (microcolumns). The procedure, however, is suitable for speeding up the determination of adsorption parameters of dye onto the adsorbent and for speeding up the initial screening of a large adsorbent collection that can be tedious if a several adsorbents and adsorption conditions must be tested. The performance of methylene blue (MB), a basic dye, Cibacron reactive black (RB) and Cibacron reactive yellow (RY) was predicted in this way and the influence of initial dye concentration and other adsorption conditions on the adsorption behaviour were demonstrated. On the basis of the experimental results, it can be concluded that the adsorption of RY onto manganese oxides modified diatomite (MOMD) exhibited a characteristic "S" shape and can be simulated effectively by the Thomas model. It is shown that the adsorption capacity increased as the initial dye concentration increased. The increase in the dye uptake capacity with the increase of the adsorbent mass in the column was due to the increase in the surface area of adsorbent, which provided more binding sites for the adsorption. It is shown that the use of high flow rates reduced the time that RY in the solution is in contact with the MOMD, thus allowing less time for adsorption to occur, leading to an early breakthrough of RY. A rapid decrease in the column adsorption capacity with an increase in particle size with an average 56% reduction in capacity resulting from an increase in the particle size from 106-250 microm to 250-500 microm. The experimental data correlated well with calculated data using the Thomas equation and the bed depth-service time (BDST) equation. Therefore, it might be concluded that the Thomas equation and the BDST equations can produce accurate predication for variation of dye concentration, mass of the adsorbent, flow rate and particle size. In general, the values of adsorption isotherm capacity obtained in a batch system show the maximum values and are considerably higher than those obtained in a fixed-bed.
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Affiliation(s)
- M A Al-Ghouti
- Royal Scientific Society, Industrial Chemistry Centre, P.O. Box 1438, Al-Jubaiha 11941, Jordan.
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Khraisheh MAM, Al-Ghouti MA, Allen SJ, Ahmad MN. Effect of OH and silanol groups in the removal of dyes from aqueous solution using diatomite. Water Res 2005; 39:922-932. [PMID: 15743639 DOI: 10.1016/j.watres.2004.12.008] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2004] [Revised: 07/15/2004] [Accepted: 12/21/2004] [Indexed: 05/24/2023]
Abstract
The removal of methylene blue, reactive black (C-NN), and reactive yellow (MI-2RN) from aqueous solution by calcined and raw diatomite at 980 degrees C was studied. These studies demonstrated the importance of the various functional groups on the mechanism of adsorption. The role of pore size distribution in the dye adsorption studies was also investigated. The adsorption isotherms were pH dependent. Henry and Freundlich adsorption isotherms were used to model the adsorption behavior and experimental results for all dyes used exhibited heterogeneous surface binding. The removal of the ionisable functional groups increased the pH(ZPC) value from 5.4 to 7.7, while FTIR, SEM and XRD analysis showed a remarkable decrease of the characteristic Si-OH peaks after calcinations at 980 degrees C. The removal of hydroxyl groups from the surface of diatomite lead to a decrease in the adsorption. It was evident from pH and infrared spectra results that mechanisms of methylene blue and reactive yellow adsorption differed from that of reactive black. Accordingly, adsorption on the external surface by n-pi interaction between the pi system of the RB and the electron lone pairs of the oxygen atoms of siloxane group and columbic attraction between the dye and the surface of calcined diatomite was proposed as a possible adsorption mechanism.
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Affiliation(s)
- M A M Khraisheh
- Department of Civil and Environmental Engineering, University College London, Gower Street, London WC1E 6BT, UK.
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Zaman MU, Hussain R, Sajjad Z, Ahmad MN. Localization of upper GI bleed on delayed imaging with 99mTc tagged RBC angiogram. J PAK MED ASSOC 2004; 54:490-1. [PMID: 15518376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Affiliation(s)
- M U Zaman
- Nuclear Medicine Section, Department of Radiology, Aga Khan University Hospital, Karachi
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Ahmad MN, Uddin N, Muzaffar S, Adil SN, Tasneem Z. Extradural extramedullary hematopoiesis: a rare MRI diagnosis with atypical features. J PAK MED ASSOC 2004; 54:221-3. [PMID: 15242004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Affiliation(s)
- M N Ahmad
- Department of Radiology, Aga Khan University Hospital, Karachi
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Al-Ghouti MA, Khraisheh MAM, Allen SJ, Ahmad MN. The removal of dyes from textile wastewater: a study of the physical characteristics and adsorption mechanisms of diatomaceous earth. J Environ Manage 2003; 69:229-238. [PMID: 14580724 DOI: 10.1016/j.jenvman.2003.09.005] [Citation(s) in RCA: 233] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The feasibility of using diatomite for the removal of the problematic reactive dyes as well as basic dyes from textile wastewater was investigated. Methylene blue, Cibacron reactive black and reactive yellow dyes were considered. Physical characteristics of diatomite such as pHsolution, pHZPC, surface area, Fourier transform infrared, and scanning electron microscopy were investigated. The surface area of diatomite was found to be 27.80 m2g(-1) and the pHZPC occurred around pH of 5.4. The results indicated that the surface charge of diatomite decreased as the pH of the solution increased with the maximum methylene blue removal from aqueous solution occurring at basic pH of around (10-11). Adsorption isotherms of diatomite with methylene blue, hydrolysed reactive black and yellow dyes were constructed at different pH values, initial dye concentrations and particle sizes. The experimental results were fitted to the Langmuir, Freundlich, and Henry models. The study indicated that electrostatic interactions play an important role in the adsorption of dyes onto diatomite. A model of the adsorption mechanism of methylene blue onto diatomite is proposed.
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Affiliation(s)
- M A Al-Ghouti
- School of Chemical Engineering, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, Northern Ireland, UK
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Abstract
Tuberculomas (TB) can mimic brain tumors and abscesses. We performed prospective magnetization transfer ratio (MTR) analysis on 60 patients with 52 intracranial TB, 13 pyogenic abscesses and 65 tumors to determine the efficacy of magnetization transfer (MT) imaging in the differential diagnosis of brain tumors and infection. The nonenhancing cores of TB had significantly higher (P=.026) MTR (0.14+/-0.29) than necrotic components of high-grade gliomas (-0.19+/-0.22). The MTR of cores of TB were also higher than those of the cystic areas of low-grade gliomas (-0.53+/-0.32), benign (-0.09+/-0.21) and malignant (-0.07+/-0.25) tumors, and abscesses (-0.03+/-0.13), but the differences were not significant because of the small number of tumors and abscesses. There was also no significant difference between the MTR of abscesses, malignant and benign tumors. Using the criteria of MTR of necrotic center > 0.14 (mean MTR of TB) for diagnosing TB, MTR <-0.03 (mean MTR of abscesses) for diagnosing tumors and MTR between these values for diagnosing abscesses, MTI had diagnostic sensitivity of 68.42%, specificity of 80.49%, and accuracy of 76.67%. The improved diagnostic accuracy of MRI with the addition of MTR analysis from 86.67% to 91.67% and from 85.71% to 87.50% for both radiologists respectively was not significant. MTR analysis helped us to differentiate solitary TB or abscess from low-grade glioma in five patients and to diagnose multiple TB, abscesses, and metastases in four.
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Affiliation(s)
- M H Pui
- Department of Radiology, Aga Khan University Hospital, Karachi, Pakistan.
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ul Haq T, Sheikh MY, Jadun CK, Ahmad MN, Husen YH. Percutaneous removal of biliary stone from anomalous right hepatic duct. J PAK MED ASSOC 1997; 47:94-6. [PMID: 9131863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- T ul Haq
- Department of Radiology, Aga Khan University Hospital, Karachi
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Ahmad MN, Zargar HU, Shahdad NA, Sapru A, Kaur S. Tuberculosis of gall bladder (a case report). J Postgrad Med 1983; 29:258-60. [PMID: 6672186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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