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Biocompatibility of cobalt iron oxide magnetic nanoparticles in male rabbits
Furhan Iqbal,Tanveer Ahmad Tabish,Muhammad Naeem Ashiq,Muhammad Azeem Ullah,Shahid Iqbal,Muhammad Latif,Muhammad Ali,Muhammad Fahad Ehsan 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.7
Present study was conducted to study the in vivo biocompatibility of cobalt iron oxide magnetic nano-particles (CoFe2O4 MNPs) in rabbits. CoFe2O4 MNPs were synthesized by the conventional micro emulsion technique in crystallite size range of 30 to 50 nm. The lattice constant (a) and cell volume were found to be 8.386 Å and 589.75 Å3, respectively, revealed by XRD. Subject animals were divided in three groups--low dose, high dose and control group without nanoparticles implantation for biocompatibility evaluation. CoFe2O4 was intraperitoneally implanted in rabbits: low dose (1mg CoFe2O4/Kg body weight) and high dose (10mg CoFe2O4/Kg body weight). Blood, serum and histological study of vital organs (liver, heart, kidney and spleen) were carried out in seven days of time protocol after sacrificing of animals. Results indicated that CoFe2O4 had drastically affected the blood chemistry in a dose-dependent manner as RDWa (P=0.01), Platelet (P<0.001) and Plateletcrit (P<0.001) concentrations reduced significantly in low dose and high dose CoFe2O4 treatments as compared to sham treated control group. Histological analysis revealed that CoFe2O4 exposure resulted in disordered and abnormal histology of liver, kidney and that of muscles at surgical site. It is concluded that CoFe2O4 has low biocompatibility and higher toxicity levels in living system at the applied doses.
New penta-saccharide-bearing tripod amphiphiles for membrane protein structure studies
Ehsan, Muhammad,Ghani, Lubna,Du, Yang,Hariharan, Parameswaran,Mortensen, Jonas S.,Ribeiro, Orquidea,Hu, Hongli,Skiniotis, Georgios,Loland, Claus J.,Guan, Lan,Kobilka, Brian K.,Byrne, Bernadette,Chae, Royal Society of Chemistry 2017 The Analyst Vol.142 No.20
<P>Integral membrane proteins either alone or as complexes carry out a range of key cellular functions. Detergents are indispensable tools in the isolation of membrane proteins from biological membranes for downstream studies. Although a large number of techniques and tools, including a wide variety of detergents, are available, purification and structural characterization of many membrane proteins remain challenging. In the current study, a new class of tripod amphiphiles bearing two different penta-saccharide head groups, designated TPSs, were developed and evaluated for their ability to extract and stabilize a range of diverse membrane proteins. Variations in the structures of the detergent head and tail groups allowed us to prepare three sets of the novel agents with distinctive structures. Some TPSs (TPS-A8 and TPS-E7) were efficient at extracting two proteins in a functional state while others (TPS-E8 and TPS-E10L) conferred marked stability to all membrane proteins (and membrane protein complexes) tested here compared to a conventional detergent. Use of TPS-E10L led to clear visualization of a receptor-Gs complex using electron microscopy, indicating profound potential in membrane protein research.</P>
Vitamin E-based glycoside amphiphiles for membrane protein structural studies
Ehsan, Muhammad,Du, Yang,Molist, Iago,Seven, Alpay B.,Hariharan, Parameswaran,Mortensen, Jonas S.,Ghani, Lubna,Loland, Claus J.,Skiniotis, Georgios,Guan, Lan,Byrne, Bernadette,Kobilka, Brian K.,Chae, The Royal Society of Chemistry 2018 Organic & Biomolecular Chemistry Vol.16 No.14
<P>Membrane proteins play critical roles in a variety of cellular processes. For a detailed molecular level understanding of their biological functions and roles in disease, it is necessary to extract them from the native membranes. While the amphipathic nature of these bio-macromolecules presents technical challenges, amphiphilic assistants such as detergents serve as useful tools for membrane protein structural and functional studies. Conventional detergents are limited in their ability to maintain the structural integrity of membrane proteins and thus it is essential to develop novel agents with enhanced properties. Here, we designed and characterized a novel class of amphiphiles with vitamin E (<I>i.e.</I>, α-tocopherol) as the hydrophobic tail group and saccharide units as the hydrophilic head group. Designated vitamin E-based glycosides (VEGs), these agents were evaluated for their ability to solubilize and stabilize a set of membrane proteins. VEG representatives not only conferred markedly enhanced stability to a diverse range of membrane proteins compared to conventional detergents, but VEG-3 also showed notable efficacy toward stabilization and visualization of a membrane protein complex. In addition to hydrophile-lipophile balance (HLB) of detergent molecules, the chain length and molecular geometry of the detergent hydrophobic group seem key factors in determining detergent efficacy for membrane protein (complex) stability.</P>
Muhammad Waqas,Mohsin Qadeer,Faizuddin Faiz,Mohammad Ali Alvi,Muhammad Ehsan Bari 대한척추외과학회 2015 Asian Spine Journal Vol.9 No.3
Study Design: A retrospective chart review. Purpose: In endemic resource poor countries like Pakistan, most patients are diagnosed and treated for Potts disease on clinical and radiological grounds without a routine biopsy. The purpose of this study was to evaluate the use and effect of computed tomography (CT)-guided biopsy in the management of Potts disease since the technique is becoming increasingly available. Overview of Literature: CT-guided biopsy of spinal lesions is routinely performed. Literature on the utility of the technique in endemic resource poor countries is little. Methods: This study was conducted at the Neurosurgery section of Aga Khan University Hospital Karachi. All the patients with suspected Potts disease who underwent CT-guided biopsy during the 7 year period from 2007 to 2013 were included in this study. Details of the procedure, histopathology and microbiology were recorded. Results: One hundred and seventy-eight patients were treated for suspected Potts disease during the study period. CT-guided biopsies of the spinal lesions were performed in 91 patients (51.12%). Of the 91 procedures, 22 (24.2%) were inconclusive because of inadequate sample (10), normal tissue (6) or reactive tissue (6). Sixty-nine biopsies were positive (75.8%). Granulomatous inflammation was seen in 58 patients (84.05%), positive acid-fast bacillus (AFB) smear in 4 (5.7%) and positive AFB culture in 12 patients (17.3%). All 91 cases in which CT-guided biopsy was performed responded positively to antituberculosis therapy (ATT). Conclusions: 75.8% of the specimens yielded positive diagnoses. Granulomatous inflammation on histopathology was the commonest diagnostic feature. In this series, the rates of positive AFB smear and culture were low compared to previous literature.
( Muhammad Ibrahim Rajoka ),( Sobia Idrees ),( Usman Ali Ashfaq ),( Beenish Ehsan ),( Asma Haq ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.1
Thermostable enzymes derived from Thermotoga maritima have attracted worldwide interest for their potential industrial applications. Structural analysis and docking studies were preformed on T. maritima β-glucosidase enzyme with cellobiose and pNP-linked substrates. The 3D structure of the thermostable β-glucosidase was downloaded from the Protein Data Bank database. Substrates were downloaded from the PubCehm database and were minimized using MOE software. Docking of BglA and substrates was carried out using MOE software. After analyzing docked enzyme/substrate complexes, it was found that Glu residues were mainly involved in the reaction, and other important residues such as Asn, Ser, Tyr, Trp, and His were involved in hydrogen bonding with pNP-linked substrates. By determining the substrate recognition pattern, a more suitable β-glucosidase enzyme could be developed, enhancing its industrial potential.
( Muhammad Ahsan Qureshi ),( Ehsan Mostajeran ),( Rafidah Md Noor ),( Azra Shamim ),( Chih-heng Ke ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.9
Vehicular Ad Hoc Networks (VANETs) utilize radio propagation models (RPMs) to predict path loss in vehicular environment. Modern urban vehicular environment contains road infrastructure units that include road tunnels, straight roads, curved roads flyovers and underpasses. Different RPMs were proposed in the past to predict path loss, but modern road infrastructure units especially flyovers and underpasses are neglected previously. Most of the existing RPMs are computationally complex and ignore some of the critical features such as impact of infrastructure units on the signal propagation and the effect of both static and moving radio obstacles on signal attenuation. Therefore, the existing RPMs are incapable of predicting path loss in flyovers and underpass accurately. This paper proposes an RPM to predict path loss for vehicular communication on flyovers and inside underpasses that considers both the static and moving radio obstacles while requiring only marginal overhead. The proposed RPM is validated based upon the field measurements in 5 GHz frequency band. A close agreement is found between the measured and predicted values of path loss.
Rajeev Kumar,Muhammad Ehsan,M.A. Barakat 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.6
In this work, flake like carbon/AlOOH composite has been synthesized and evaluated as a new adsorbentfor the removal of Cr(VI) from synthetic wastewater. Different characterization tools such as, SEM, EDAX,XRD and XPS were performed to characterize the composite material. Batch adsorption studies for Cr(VI)removal were performed under the influence of various operational parameters such as solution pH,contact time, initial solution concentration and temperature. Results obtained revealed that adsorptionof Cr(VI) onto carbon/AlOOH composite followed the pseudo-second order kinetics and Freundlichisotherm model. Thermodynamic results suggests that adsorption of Cr(VI) onto carbon/AlOOHcomposite was spontaneous and endothermic in nature.
Hannan Younis,Sumbilah Shafique,Zahida Ehsan,Aleena Ishfaq,Khurram Mehboob,Muhammad Ajaz,Abdullah Hidayat,Wazir Muhammad Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.7
The radioactivity concentrations of Naturally Occurring Radioactive Materials (NORM) i.e., <sup>226</sup>Ra, <sup>232</sup>Th, and <sup>4</sup>K in various chemical fertilizers being used in the agricultural soil of Pakistan were determined utilizing gamma spectrometry by employing a High Purity Germanium (HPGe) detector. The radioactivity concentrations of <sup>226</sup>Ra, <sup>232</sup>Th, and <sup>4</sup>K extended from 2.58 ± 0.8-265.7 ± 8.8 Bq kg<sup>-1</sup>, 1.53 ± 0.14-76.6 ± 1.07 Bq kg<sup>-1</sup> and 36.5 ± 1.34-15606.7 ± 30.2 Bq kg<sup>-1</sup> respectively. The radiological hazard parameters such as internal and external indices and annual effective dose rates were calculated, while excessive lifetime cancer risk factors for the indoor and outdoor areas were found in the range from 0.3×10<sup>-3</sup> to 10.723×10<sup>-3</sup> and 0.03×10<sup>-3</sup> to 2.7948×10<sup>-3</sup> of most fertilizers, however, some values were slightly higher than the UNSCEAR (The United Nations Scientific Committee on the Effects of Atomic Radiation) recommended values for potash-containing fertilizers such as MOP (Muriate of Potash).
Chae, Pil Seok,Bae, Hyoung Eun,Ehsan, Muhammad,Hussain, Hazrat,Kim, Jin Woong The Royal Society of Chemistry 2014 Organic & Biomolecular Chemistry Vol.12 No.42
<P>Detergents are widely used for membrane protein research; however, membrane proteins encapsulated in micelles formed by conventional detergents tend to undergo structural degradation, necessitating the development of new agents with enhanced efficacy. Here we prepared several hydrophobic variants of ganglio-tripod amphiphiles (TPAs) derived from previously reported TPAs and evaluated for a multi-subunit, pigment protein superassembly. In this study. TPA-16 was found to be most efficient in protein solubilization while TPA-15 proved most favourable in long-term protein stability. The current study combined with previous TPA studies enabled us to elaborate on a few detergent structure-property relationships that could provide useful guidelines for novel amphiphile design.</P>