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Hasan M, Rafique S, Zafar A, Loomba S, Khan R, Hassan SG, Khan MW, Zahra S, Zia M, Mustafa G, Shu X, Ihsan Z, Mahmood N. Physiological and anti-oxidative response of biologically and chemically synthesized iron oxide: Zea mays a case study. Heliyon 2020; 6:e04595. [PMID: 32923707 PMCID: PMC7475124 DOI: 10.1016/j.heliyon.2020.e04595] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/03/2020] [Accepted: 07/28/2020] [Indexed: 01/31/2023] Open
Abstract
The synthesis methodology, particle size and shape, dose optimization, and toxicity studies of nano-fertilizers are vital prior to their field application. This study investigates the comparative response of chemically synthesized and biologically synthesized iron oxide nanorods (NRs) using moringa olefera along with bulk FeCl3 on summer maize (Zea mays). It is found that FeCl3 salt and chemically synthesized iron oxides NRs caused growth retardation and impaired plant physiological and anti-oxidative activities at a concentration higher than 25 mg/L due to toxicity by over accumulation. While iron released form biologically synthesized NRs have shown significantly positive results even at 50 mg/L due to their low toxicity, an improved leaf area (13%), number of leaves per plant (26%), total chlorophyll content (80%) and nitrate content (6%) with biologically synthesized NRs are obtained. Moreover, the plant anti-oxidative activity also increased on treatment with biologically synthesized NRs because of their ability to form a complex with metal ions. These findings suggest that biologically synthesized iron oxides NRs are an efficient iron source and can last for a long time. Thus, proving that nanofertilizer are required to have specific surface chemistry to release the nutrient in an appropriate concentration for better plant growth.
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Hasan M, Zafar A, Shahzadi I, Luo F, Hassan SG, Tariq T, Zehra S, Munawar T, Iqbal F, Shu X. Fractionation of Biomolecules in Withania coagulans Extract for Bioreductive Nanoparticle Synthesis, Antifungal and Biofilm Activity. Molecules 2020; 25:E3478. [PMID: 32751780 PMCID: PMC7435783 DOI: 10.3390/molecules25153478] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/16/2020] [Accepted: 07/20/2020] [Indexed: 12/13/2022] Open
Abstract
Withania coagulans contains a complex mixture of various bioactive compounds. In order to reduce the complexity of the plant extract to purify its phytochemical biomolecules, a novel fractionation strategy using different solvent combination ratios was applied to isolate twelve bioactive fractions. These fractions were tested for activity in the biogenic synthesis of cobalt oxide nanoparticles, biofilm and antifungal activities. The results revealed that plant extract with bioactive fractions in 30% ratio for all solvent combinations showed more potent bioreducing power, according to the observed color changes and the appearance of representative absorption peaks at 500-510 nm in the UV-visible spectra which confirm the synthesis of cobalt oxide nanoparticles (Co3O4 NPs). XRD diffraction was used to define the crystal structure, size and phase composition of the products. The fractions obtained using 90% methanol/hexane and 30% methanol/hexane showed more effectiveness against biofilm formation by Pseudomonas aeruginosa and Staphylococcus aureus so these fractions could potentially be used to treat bacterial infections. The 90% hexane/H2O fraction showed excellent antifungal activity against Aspergillus niger and Candida albicans, while the 70% methanol/hexane fraction showed good antifungal activity for C. albicans, so these fractions are potentially useful for the treatment of various fungal infections. On the whole it was concluded that fractionation based on effective combinations of methanol/hexane was useful to investigate and study bioactive compounds, and the active compounds from these fractions may be further purified and tested in various clinical trials.
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Hanif M, Arshad J, Astin JW, Rana Z, Zafar A, Movassaghi S, Leung E, Patel K, Söhnel T, Reynisson J, Sarojini V, Rosengren RJ, Jamieson SMF, Hartinger CG. A Multitargeted Approach: Organorhodium Anticancer Agent Based on Vorinostat as a Potent Histone Deacetylase Inhibitor. Angew Chem Int Ed Engl 2020; 59:14609-14614. [PMID: 32431061 DOI: 10.1002/anie.202005758] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Indexed: 12/22/2022]
Abstract
The combination of more than one bioactive moiety in a multitargeted anticancer agent may result in synergistic activity of its components. Using this concept, bioorganometallic compounds were designed to feature a metal center, a 2-pyridinecarbothioamide (PCA), and a hydroxamic acid, which is found in the anticancer drug vorinostat (SAHA). The organometallics showed inhibitory activity in the nanomolar range against histone deacetylases (HDACs) as the key target for SAHA. In particular, the Rh complex was a potent inhibitor of HDAC6 over HDAC1 and HDAC8. Whereas this complex was highly cytotoxic in human cancer cells, it showed low toxicity in hemolysis studies and zebrafish, demonstrating the role of the metal center. For this complex a slightly reduced expression of vascular endothelial growth factor receptor 2 (VEGFR2) was established, which was upregulated by SAHA. This finding indicates that the new organometallics display different modes of action than their bioactive components.
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Mabray MC, Starcevich J, Hallstrom J, Robinson M, Bartlett M, Nelson J, Zafar A, Kim H, Morrison L, Hart BL. High Prevalence of Spinal Cord Cavernous Malformations in the Familial Cerebral Cavernous Malformations Type 1 Cohort. AJNR Am J Neuroradiol 2020; 41:1126-1130. [PMID: 32467184 DOI: 10.3174/ajnr.a6584] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 03/19/2020] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND PURPOSE Cavernous malformations occur most often in the brain but can occur in the spinal cord. Small studies of patients with familial cerebral cavernous malformations suggested a prevalence of spinal cord cavernous malformations of 20%-42%. We aimed to review our familial cohort and prospectively estimate the prevalence of spinal cord cavernous malformations. MATERIALS AND METHODS We initially reviewed our familial cerebral cavernous malformations cohort for spinal cord cavernous malformations and reviewed clinical spine MR imaging examinations for sequence sensitivity. We then prospectively performed research MR imaging of the spinal cord in 29 patients from the familial cohort to estimate the prevalence. RESULTS Gradient-based sequences identified the most spinal cord cavernous malformations on clinical MR images, forming the basis for developing our screening MR imaging. Screening spinal cord MR imaging demonstrated a prevalence of 72.4%, and a positive correlation with patient age and number of cerebral cavernous malformations. CONCLUSIONS Spinal cord cavernous malformations occur commonly in the familial cerebral cavernous malformation population. Gradient-based sequences are the most sensitive and should be used when spinal cord cavernous malformations are suspected. This study establishes the prevalence in the familial population at around 70% and supports the idea that this condition is a progressive systemic disease that affects the entire central nervous system.
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Luo F, Wang M, Huang L, Wu Z, Wang W, Zafar A, Tian Y, Hasan M, Shu X. Synthesis of Zinc Oxide Eudragit FS30D Nanohybrids: Structure, Characterization, and Their Application as an Intestinal Drug Delivery System. ACS OMEGA 2020; 5:11799-11808. [PMID: 32478271 PMCID: PMC7254796 DOI: 10.1021/acsomega.0c01216] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/04/2020] [Indexed: 05/03/2023]
Abstract
The present study was designed to develop multifunctional zinc oxide-encapsulated Eudragit FS30D (ZnO/EFS) nanohybrid structures as a biodegradable drug delivery system and as a promising successful carrier for targeting sites. The solvent evaporation method was used to fabricate the ZnO/EFS nanohybrids and the size, shape, stability, and antioxidant activity were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), thermogravimetric analysis (TGA), and an antioxidant (1,1-diphenyl-2-picrylhydrazyl (DPPH)). Zinc oxide-encapsulated Eudragit FS30D (ZnO/EFS) nanohybrid structures consisted of irregularly shaped, 297.65 nm-sized ZnO/EFS microcapsule, enduring thermal stability from 251.17 to 385.67 °C. Nano-ZnO was encapsulated in EFS through the formation of hydrogen bonds, and the average encapsulation efficiency for nano-ZnO was determined to be 96.12%. In vitro intestinal-targeted drug release assay provided 91.86% with free nano-ZnO, only 9.5% in acidified ZnO/EFS nanohybrid structure but the rate ZnO/EFS nanohybrids reached 93.11% in succus entericus resultantly modified nano-ZnO was proven proficient intestinal-specific delivery system. The stability of the ZnO/EFS nanohybrid structures was confirmed using ζ-potential and antioxidant activity analysis. Hence, the EFS nanoencapsulation strategy of ZnO provided a stable, nontoxic, and pharmacokinetically active intestine-specific system that can become the best choice for an effective oral feed additive in future.
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Nisa ZU, Zafar A, Zafar F, Pezaro S, Sher F. Adverse Drug Reaction Monitoring and Reporting Among Physicians and Pharmacists in Pakistan: A Cross-sectional Study. Curr Drug Saf 2020; 15:137-146. [PMID: 32338223 DOI: 10.2174/1574886315666200427120322] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 03/30/2020] [Accepted: 04/06/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND The success of a reporting system of adverse drug reaction (ADR) depends on the knowledge, attitudes, and practices of the health care professionals. However, due to a lack of knowledge and poor contribution by healthcare workers, ADR remains underreported. To improve safety, proper identification and ADR reporting is necessary. OBJECTIVE This study was carried out to determine knowledge, attitude, and practices of ADR among physicians and pharmacists working in Pakistan and the factors which encourage and discourage effective reporting. METHODS A cross-sectional study was conducted using a pretested questionnaire. Questionnaires were distributed among 333 physicians and 34 pharmacists with a 95.5% response rate. The Statistical Package for Social Science (SPSS) was used for data analysis. RESULTS Pharmacists have more knowledge regarding ADR compared to physicians (47.1% vs. 13.8%, p < 0.001). Pharmacists also have a positive attitude compared to physicians (97.1% vs. 76.3%, p < 0.001). No significant difference was noticed in ADR practice by physicians and pharmacists (12.3% vs. 11.8, p = 0.92). The seriousness of ADR was the main factor that encouraged nearly all pharmacists to report, whereas among physician's, seriousness and the unusualness of reaction, the new drug involvement, and confidence in diagnosis were the factors which encouraged them to report ADR. CONCLUSION Overall, pharmacists had more knowledge and a positive attitude regarding ADR reporting compared to physicians, but practices of ADR reporting remained the same among both. Therefore, it is suggested that educational interventions, along with training programs, should be developed.
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Qasim S, Zafar A, Saif MS, Ali Z, Nazar M, Waqas M, Haq AU, Tariq T, Hassan SG, Iqbal F, Shu XG, Hasan M. Green synthesis of iron oxide nanorods using Withania coagulans extract improved photocatalytic degradation and antimicrobial activity. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2020; 204:111784. [DOI: 10.1016/j.jphotobiol.2020.111784] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 12/06/2019] [Accepted: 01/09/2020] [Indexed: 10/25/2022]
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Chepanova AA, Li-Zhulanov NS, Sukhikh AS, Zafar A, Reynisson J, Zakharenko AL, Zakharova OD, Korchagina DV, Volcho KP, Salakhutdinov NF, Lavrik OI. Effective Inhibitors of Tyrosyl-DNA Phosphodiesterase 1 Based on Monoterpenoids as Potential Agents for Antitumor Therapy. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2020. [DOI: 10.1134/s1068162019060104] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Leung E, Pilkington LI, Naiya MM, Barker D, Zafar A, Eurtivong C, Reynisson J. The cytotoxic potential of cationic triangulenes against tumour cells. MEDCHEMCOMM 2019; 10:1881-1891. [PMID: 32952994 PMCID: PMC7478161 DOI: 10.1039/c9md00305c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 08/19/2019] [Indexed: 12/20/2022]
Abstract
TOTA (trioxatriangulenium ion) is a close-shelled carbocation known to intercalate strongly with the DNA double helix (J. Reynisson, G. B. Schuster, S. B. Howerton, L. D. Williams, R. N. Barnett, C. L. Cleveland, U. Landman, N. Harrit, J. B. Chaires, J. Am. Chem. Soc. 2003, 125, 2072). The cytotoxicity of TOTA and its four close structural analogues, ADOTA, Pr-ADOTA, Pr-DAOTA and n-Butyl-TATA were tested against the breast cancer cell line MDA-MB-231 and colon cancer cell line HCT116. The most potent derivatives Pr-ADOTA and Pr-DAOTA had IC50 values of ∼80 nM for MDA-MB-231 but slightly higher for HCT116 in the low hundreds nM range. A 3D model assay of HCT116 spheroids was also used, mimicking a tumour environment, again both Pr-ADOTA and Pr-DAOTA were very active with IC50 values of 38 nM and 21 nM, respectively. Molecular modelling suggest that the planar derivatives intercalate between the base pairs of the DNA double helix. However, only modest DNA double stranded DNA cleavage was observed using the γH2AX assay as compared to camptothecin, a topoisomerase I poison suggesting a different mechanism. Finally, a robust density functional theory (DFT) model was built to predict the pK R+ stability values, i.e., to design derivatives, which predominantly have a non-intercalating buckled form in healthy tissues followed by a nucleophilic attach of water on the central carbon, but a planar form at relatively low pH values rendering them only cytotoxic in the interior of tumours.
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Zulfiqar H, Zafar A, Rasheed MN, Ali Z, Mehmood K, Mazher A, Hasan M, Mahmood N. Synthesis of silver nanoparticles using Fagonia cretica and their antimicrobial activities. NANOSCALE ADVANCES 2019; 1:1707-1713. [PMID: 36134229 PMCID: PMC9473189 DOI: 10.1039/c8na00343b] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 12/03/2018] [Indexed: 05/21/2023]
Abstract
Silver nanoparticles (NPs) were synthesized using an efficient bioreducing agent from Fagonia cretica extract having the advantage of eco-friendliness over chemical and physical methods. The sharp color change and appearance of representative absorption peaks in the UV-visible spectra confirm the quick reduction of the Ag salt and evolution of Ag NPs. Morphological and structural aspects showed that the resulting Ag NPs are highly crystalline with an average size of 16 nm. Furthermore, compositional analysis of the extract confirmed the existence of active bioreducing and stabilizing agents in the Fagonia cretica extract. Furthermore, various concentrations of AgNO3 and the Fagonia cretica extract were employed to obtain a higher yield with better stability of Ag NPs. The resulting Ag NPs showed effective antibacterial activity against Proteus vulgaris, Escherichia coli, and Klebsiella pneumoniae. It is found that the Ag NPs induce maximum production of reactive oxygen species (ROS) in Proteus vulgaris as compared to Escherichia coli and Klebsiella pneumoniae which induce cell toxicity, while ROS production in the presence of Ag NPs is 30% higher than that in the presence of only the plant extract and control in all three bacterial strains. Thus, present findings show that plant extracts can be a useful natural resource to prepare functional nanomaterials for targeted applications especially in the field of biotechnology.
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Ashraf A, Aman F, Movassaghi S, Zafar A, Kubanik M, Siddiqui WA, Reynisson J, Söhnel T, Jamieson SMF, Hanif M, Hartinger CG. Structural Modifications of the Antiinflammatory Oxicam Scaffold and Preparation of Anticancer Organometallic Compounds. Organometallics 2019. [DOI: 10.1021/acs.organomet.8b00751] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Zafar A, Rushton N. Extruded collagen fibres and biphasic collagen sponge for rotator cuff tendon repair application: an ovine in vitro study. Muscles Ligaments Tendons J 2019. [DOI: 10.32098/mltj.04.2018.13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Yousaf A, Zafar A, Ali M, Bukhary SM, Manzoor Y, Tariq T, Saeed A, Akram M, Bukhari F, Abdullah M, Zehra SS, Hassan SG, Hasan M. Intrinsic Bio-Enhancer Entities of <i>Fagonia cretica</i> for Synthesis of Silver Nanoparticles Involves Anti-Urease, Anti-Oxidant and Anti-Tyosinase Activity. ACTA ACUST UNITED AC 2019. [DOI: 10.4236/abb.2019.1012032] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Bibi S, Zafar A, Anwar S, Farooqui B, Qureshi H. Laboratory Based Surveillance of Pneumococcal Serotypes causing Invasive and Non-Invasive Infections in Karachi, Pakistan. J Infect Public Health 2019. [DOI: 10.1016/j.jiph.2018.10.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Ohui K, Afanasenko E, Bacher F, Ting RLX, Zafar A, Blanco-Cabra N, Torrents E, Dömötör O, May NV, Darvasiova D, Enyedy ÉA, Popović-Bijelić A, Reynisson J, Rapta P, Babak MV, Pastorin G, Arion VB. New Water-Soluble Copper(II) Complexes with Morpholine-Thiosemicarbazone Hybrids: Insights into the Anticancer and Antibacterial Mode of Action. J Med Chem 2018; 62:512-530. [PMID: 30507173 PMCID: PMC6348444 DOI: 10.1021/acs.jmedchem.8b01031] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
![]()
Six
morpholine-(iso)thiosemicarbazone hybrids HL1–HL6 and
their Cu(II) complexes with good-to-moderate solubility and
stability in water were synthesized and characterized. Cu(II) complexes [Cu(L1–6)Cl] (1–6) formed weak dimeric associates in the solid state,
which did not remain intact in solution as evidenced by ESI-MS. The
lead proligands and Cu(II) complexes displayed higher antiproliferative
activity in cancer cells than triapine. In addition, complexes 2–5 were found to specifically inhibit the growth of
Gram-positive bacteria Staphylococcus aureus with MIC50 values at 2–5 μg/mL. Insights
into the processes controlling intracellular accumulation and mechanism
of action were investigated for 2 and 5,
including the role of ribonucleotide reductase (RNR) inhibition, endoplasmic
reticulum stress induction, and regulation of other cancer signaling
pathways. Their ability to moderately inhibit R2 RNR protein in the
presence of dithiothreitol is likely related to Fe chelating properties
of the proligands liberated upon reduction.
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Lam NYS, Truong D, Burmeister H, Babak MV, Holtkamp HU, Movassaghi S, Ayine-Tora DM, Zafar A, Kubanik M, Oehninger L, Söhnel T, Reynisson J, Jamieson SMF, Gaiddon C, Ott I, Hartinger CG. From Catalysis to Cancer: Toward Structure-Activity Relationships for Benzimidazol-2-ylidene-Derived N-Heterocyclic-Carbene Complexes as Anticancer Agents. Inorg Chem 2018; 57:14427-14434. [PMID: 30406647 DOI: 10.1021/acs.inorgchem.8b02634] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The promise of the metal(arene) structure as an anticancer pharmacophore has prompted intensive exploration of this chemical space. While N-heterocyclic carbene (NHC) ligands are widely used in catalysis, they have only recently been considered in metal complexes for medicinal applications. Surprisingly, a comparatively small number of studies have been reported in which the NHC ligand was coordinated to the RuII(arene) pharmacophore and even less with an OsII(arene) pharmacophore. Here, we present a systematic study in which we compared symmetrically substituted methyl and benzyl derivatives with the nonsymmetric methyl/benzyl analogues. Through variation of the metal center and the halido ligands, an in-depth study was conducted on ligand exchange properties of these complexes and their biomolecule binding, noting in particular the stability of the M-CNHC bond. In addition, we demonstrated the ability of the complexes to inhibit the selenoenzyme thioredoxin reductase (TrxR), suggested as an important target for anticancer metal-NHC complexes, and their cytotoxicity in human tumor cells. It was found that the most potent TrxR inhibitor diiodido(1,3-dibenzylbenzimidazol-2-ylidene)(η6-p-cymene)ruthenium(II) 1bI was also the most cytotoxic compound of the series, with the antiproliferative effects in general in the low to middle micromolar range. However, since there was no clear correlation between TrxR inhibition and antiproliferative potency across the compounds, TrxR inhibition is unlikely to be the main mode of action for the compound type and other target interactions must be considered in future.
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Zakharenko AL, Luzina OA, Sokolov DN, Kaledin VI, Nikolin VP, Popova NA, Patel J, Zakharova OD, Chepanova AA, Zafar A, Reynisson J, Leung E, Leung IKH, Volcho KP, Salakhutdinov NF, Lavrik OI. Novel tyrosyl-DNA phosphodiesterase 1 inhibitors enhance the therapeutic impact of topoteсan on in vivo tumor models. Eur J Med Chem 2018; 161:581-593. [PMID: 30396105 DOI: 10.1016/j.ejmech.2018.10.055] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 10/18/2018] [Accepted: 10/22/2018] [Indexed: 02/07/2023]
Abstract
The druggability of the tyrosyl-DNA phosphodiesterase 1 (Tdp1) enzyme was investigated in conjunction with topoisomerase 1 inhibition. A novel class of thiazole, aminothiazole and hydrazonothiazole usnic acid derivatives was synthesized and evaluated as Tdp1 inhibitors and their ability to sensitize tumors to topotecan, a topoisomerase inhibitor in clinical use. Of all the compounds tested, four hydrazinothiazole derivatives, 20c, 20d, 20h and 20i, inhibited the enzyme in the nanomolar range. The activity of the compounds was verified by affinity experiments as well as supported by molecular modelling. The most effective Tdp1 inhibitor, 20d, was ton-toxic and increased the effect of topotecan both in vitro and in vivo in the Lewis lung carcinoma model. Furthermore, 20d showed significant increase in the antitumor and antimetastatic effect of topotecan in mice. The results presented here justify compound 20d to be considered as a drug lead for antitumor therapy.
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Singal M, Zafar A, Tbakhi B, Jadhav N, Alweis R, Bhavsar H. Assessment of knowledge and attitudes towards safety events reporting among residents in a community health system. J Community Hosp Intern Med Perspect 2018; 8:253-259. [PMID: 30357000 PMCID: PMC6197008 DOI: 10.1080/20009666.2018.1527670] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 09/13/2018] [Indexed: 11/17/2022] Open
Abstract
Background: Resident physicians are known to be infrequent reporters of patient safety events (PSE). Previous studies assessing barriers to resident PSE reporting have not considered possible cultural barriers faced by international medical graduates (IMG). This study aimed to assess the knowledge and attitudes of residents regarding PSE and possible barriers contributing to poor resident reporting. Methods: A cross sectional survey of all house staff undergoing post-graduate residency training at two independent community hospital based academic medical centers was conducted through an online questionnaire. Sample case vignettes were created to assess the residents’ ability to identify safety events and classify them as near miss, adverse events or sentinel events and decide whether they were reportable. Results: The Reporting of PSE increased significantly by year of residency training (p < 0.005), with time taken to file a PSE being the strongest perceived barrier. There was no difference in PSE reporting between IMG’s and non- IMG’s. We identified major knowledge gaps with only 73.9%, 79.6% and 94.3% of respondents correctly identifying sentinel events, adverse events, and near misses, respectively. 58.1% of respondents did not think near misses were reportable. Conclusions: A lack of knowledge is the most important barrier towards PSE reporting. A different cultural background and lack of previous exposure to patient safety report by IMGs is not a significant barrier towards safety event reporting. In the short-term, it appears that focusing limited institutional resources on education rather than acculturation issues would have the greatest benefit.
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Faizan M, Anwar S, Kashif R, Saleem R, Javed H, Zafar A, Hameed A, Taj M, Maysam H, Miguela C, Rathore A, Sadiq M, Gonzalez M, Zaidi A. Improvement in Infection Prevention and Control Measures at The Children Hospital, Lahore. A My Child Matters Collaborative Project. J Glob Oncol 2018. [DOI: 10.1200/jgo.18.90400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: Overcrowding, lack of operational funds, and healthcare associated infections are major challenges at the Children Hospital Lahore, a public healthcare facility in Pakistan with 900 new pediatric cancer admissions annually. In 2014, a collaboration between My Child Matters (MCM), St. Jude Global Infectious Diseases Program (SJ-GID), and our institution was established to address these issues. Aim: To describe the effect of a collaborative improvement strategy on the infection prevention and control (IPC) standards in a pediatric oncology unit in a resource-limited setting. Methods: Our study was a prospective before-and-after study. We compare the WHO Hand Hygiene Self-Assessment Framework (HHSAF) and 4 modules of the St. Jude modified Infection Control Assessment Tool (ICAT) scores. Our strategy included: (1) creating a multidisciplinary team of pediatric hematology-oncology, infectious disease physicians, nurses, microbiologist, and a data manager, (2) engaging on monthly online IPC mentoring sessions with the SJ-GID and MCM mentors, (3) performing daily inpatient healthcare associated (HAI) surveillance rounds, and (4) providing regular hand hygiene training and compliance audits. Results: Our hand hygiene facility level per WHO scores increased from “Inadequate” during the baseline assessment to “Intermediate/Consolidation” by the end of 3-year implementation (122 vs 352 HHSAF scores). The sink: bed and hand sanitizer: bed ratios improved to 1:6 and 1:1 respectively. Six washrooms were added to our unit. ICAT general infection control module increased by 40% (45 vs 78 ICAT score) and hygiene compliance improved by 20% from baseline. Identification of HAI increased from baseline (4.07 vs 8.7 infections per 1000 patient days). A 25% of the isolates were multidrug-resistant microorganisms. Conclusion: Implementing a collaborative improvement strategy improved the IPC standards in our pediatric cancer center. The increase of HAI might be a result of a better surveillance and laboratory identification. Further targeted interventions should be develop to decrease HAI rates and infection-related morbidity and mortality in our population.
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Li-Zhulanov NS, Zakharenko AL, Chepanova AA, Patel J, Zafar A, Volcho KP, Salakhutdinov NF, Reynisson J, Leung IKH, Lavrik OI. A Novel Class of Tyrosyl-DNA Phosphodiesterase 1 Inhibitors That Contains the Octahydro-2 H-chromen-4-ol Scaffold. Molecules 2018; 23:E2468. [PMID: 30261631 PMCID: PMC6222798 DOI: 10.3390/molecules23102468] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 09/21/2018] [Accepted: 09/22/2018] [Indexed: 11/25/2022] Open
Abstract
Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is a DNA repair enzyme that mends topoisomerase 1-mediated DNA damage. Tdp1 is a current inhibition target for the development of improved anticancer treatments, as its inhibition may enhance the therapeutic effect of topoisomerase 1 poisons. Here, we report a study on the development of a novel class of Tdp1 inhibitors that is based on the octahydro-2H-chromene scaffold. Inhibition and binding assays revealed that these compounds are potent inhibitors of Tdp1, with IC50 and KD values in the low micromolar concentration range. Molecular modelling predicted plausible conformations of the active ligands, blocking access to the enzymatic machinery of Tdp1. Our results thus help establish a structural-activity relationship for octahydro-2H-chromene-based Tdp1 inhibitors, which will be useful for future Tdp1 inhibitor development work.
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Zakharova O, Luzina O, Zakharenko A, Sokolov D, Filimonov A, Dyrkheeva N, Chepanova A, Ilina E, Ilyina A, Klabenkova K, Chelobanov B, Stetsenko D, Zafar A, Eurtivong C, Reynisson J, Volcho K, Salakhutdinov N, Lavrik O. Synthesis and evaluation of aryliden- and hetarylidenfuranone derivatives of usnic acid as highly potent Tdp1 inhibitors. Bioorg Med Chem 2018; 26:4470-4480. [PMID: 30076000 DOI: 10.1016/j.bmc.2018.07.039] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 07/19/2018] [Accepted: 07/22/2018] [Indexed: 10/28/2022]
Abstract
Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is a repair enzyme for stalled DNA-topoisomerase 1 (Top 1) cleavage complexes and other 3'-end DNA lesions. Tdp1 is a promising target for anticancer therapy, since it can repair DNA lesions caused by Top1 inhibitors leading to drug resistance. Hence, Tdp1 inhibition should result in synergistic effect with Top1 inhibitors. Twenty nine derivatives of (+)-usnic acid were tested for in vitro Tdp1 inhibitory activity using a fluorescent-based assay. Excellent activity was obtained, with derivative 6m demonstrating the lowest IC50 value of 25 nM. The established efficacy was verified using a gel-based assay, which gave close results to that of the fluorescent assay. In addition, molecular modeling in the Tdp1 substrate binding pocket suggested plausible binding modes for the active analogues. The synergistic effect of the Tdp1 inhibitors with topotecan, a Top1 poison in clinical use, was tested in two human cell lines, A-549 and HEK-293. Compounds 6k and 6x gave very promising results. In particular, 6x has a low cytotoxicity and an IC50 value of 63 nM, making it a valuable lead compound for the development of potent Tdp1 inhibitors for clinical use.
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Zafar A, Imran M, Zahoor S, Shah ZH, Ali M, Afzal MS. Prevalence and Treatment of Untypable HCV Variants in Different Districts of Punjab, Pakistan. Viral Immunol 2018; 31:426-432. [PMID: 29920175 DOI: 10.1089/vim.2017.0167] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
In Pakistan, around 11 million people are infected with, at least, six circulating genotypes and subtypes of hepatitis C virus (HCV). The viral burden is still on rise. HCV genotype determination is necessary to devise appropriate antiviral therapy. Previous reports highlight the prevalence circulating untypable (in diagnostic perspectives) HCV subtype in local Pakistani patients. Present study was designed to investigate the epidemiological distribution of genotypes in different districts of Punjab, Pakistan and focuses on prevalence of diagnostically untypable subtype and its possible antiviral therapy. A total of 8,353 HCV patients were included through 2011 to 2016 for determination of HCV prevalent genotypes in the local community. HCV genotyping was carried out using Ohno et al. method, and five cases of diagnostically untypable patients were treated with interferon-based antiviral regimen to find the possible treatment strategy. Of the 8,353 patients, the genotype 3a (n = 6,650, 79.6%) was most significantly prevalent throughout the study period followed by undetermined genotype that is, untypable (n = 1,377, 16.5%). The presence of untypable variants suggested that there are some novel or quasi species prevailing among HCV patients in local community. Five HCV patients infected with untypable genotype had been treated effectively with interferon alpha plus ribavirin therapy for 24 weeks at standard doses and achieved sustained virological response. This study highlighted an important aspect of HCV treatment for local Pakistani HCV patients. Untypable HCV variants could be treated with interferon-based antiviral regimens such as 3a genotype. The study raises the need of characterization of diagnostically untypable HCV variant. On the basis of these results, it can be proposed that until the availability of pangenotypic direct-acting antiviral for HCV treatment in Pakistan, interferon-based antiviral regimens will be of choice for majority of patients infected with 3a or untypable genotypes.
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Arshad J, Hanif M, Zafar A, Movassaghi S, Tong KKH, Reynisson J, Kubanik M, Waseem A, Söhnel T, Jamieson SMF, Hartinger CG. Organoruthenium and Organoosmium Complexes of 2-Pyridinecarbothioamides Functionalized with a Sulfonamide Motif: Synthesis, Cytotoxicity and Biomolecule Interactions. Chempluschem 2018; 83:612-619. [PMID: 31950635 DOI: 10.1002/cplu.201800194] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 05/22/2018] [Indexed: 11/07/2022]
Abstract
Anticancer-active RuII -η6 -p-cymene complexes of bioactive 2-pyridinecarbothioamide ligands have been shown to have high selectivity for plectin and can be administered orally. Reported herein is the functionalization of a 2-pyridinecarbothioamide with a sulfonamide group and its conversion into M-η6 -p-cymene complexes (M = Ru, Os). The presence of a sulfonamide moiety in many organic drugs and metal complexes endows these agents with interesting biological properties and can transform the latter into multi-targeted agents. The compounds were characterized with standard methods and the in vitro anticancer activity data was compared with studies on the hydrolytic stability of the complexes and their reactivity to small biomolecules. A molecular modeling study revealed plausible modes of binding of the complexes in the catalytic pocket of carbonic anhydrase II.
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Nisa ZU, Zafar A, Sher F. Assessment of knowledge, attitude and practice of adverse drug reaction reporting among healthcare professionals in secondary and tertiary hospitals in the capital of Pakistan. Saudi Pharm J 2018; 26:453-461. [PMID: 29844715 PMCID: PMC5961757 DOI: 10.1016/j.jsps.2018.02.014] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Accepted: 02/05/2018] [Indexed: 12/01/2022] Open
Abstract
Adverse Drug Reactions (ADRs) underreporting is a great challenge to pharmacovigilance. Healthcare professionals should consider ADR reporting as their professional obligation because the effective system of ADR reporting is important to improve patient care and safety. This study was designed to assess the knowledge, attitude, practice and factors associated with ADR reporting by healthcare professionals (physicians and pharmacists) in secondary and tertiary hospitals of Islamabad. A pretested questionnaire comprising of 27 questions (knowledge 12, attitude 4, practice 9 and factors influencing ADR reporting 2) was administered to 384 physicians and pharmacists in public and private hospitals. Respondents were evaluated for their knowledge, attitude and practice related to ADR reporting. Additionally, the factors which encourage and discourage respondents to report ADRs were also determined. The data was analysed by using SPSS statistical software. Among 384 respondents, 367 provided responses to questionnaire, giving a response rate of 95.5%. The mean age was 28.3 (SD = 6.7). Most of the respondents indicated poor ADR reporting knowledge (83.1%). The majority of respondents (78.2%) presented a positive attitude towards ADR reporting and only a few (12.3%) hospitals have good ADR reporting practice. The seriousness of ADR, unusualness of reaction, new drug involvement and confidence in the diagnosis of ADR are the factors which encourage respondents to report ADR whereas lack of knowledge regarding where and how to report ADR, lack of access to ADR reporting form, managing patient is more important than reporting ADR legal liability issues were the major factors which discourage respondents to report ADR. The study reveals poor knowledge and practice regarding ADR reporting. However, most of the respondents have shown a positive attitude towards ADR reporting. There is a serious need for educational training as well as sincere and sustained efforts should be made by Government and Hospital Authorities to ensure proper implementation of ADR reporting system in all of the hospitals.
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Zafar A. A review of 500 patients with acute stroke admitted to the University Hospital of Saudi Arabia. Similarities and differences compared with the published literature. FUNCTIONAL NEUROLOGY 2018; 33:73-79. [PMID: 29984684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Published studies have shown differences in types and underlying mechanisms of stroke between different regions of the world. There is a lack of published literature describing the characteristics of acute stroke in Saudi Arabia. The aim of this study was to identify different types and associated risk factors among acute stroke patients in Saudi Arabia. In this descriptive study, records of 500 patients with acute stroke were included. Acute stroke was classified as ischemic stroke, intracerebral hemorrhage, cerebral venous sinus thrombosis or subarachnoid hemorrhage. The TOAST classification was used to categorize ischemic stroke. Ischemic stroke was found to be the most common type (86.6%). The patients included comprised 326 (65.2%) males and 174 (34.8%) females. Small vessel occlusive disease was the most common etiology of ischemic stroke. The males had a lower mean age than the females (p=0.00). The results of our study are largely in agreement with published literature, although a few differences emerged which need to be verified through further prospective multicenter studies.
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Ponomarev KY, Suslov EV, Zakharenko AL, Zakharova OD, Rogachev AD, Korchagina DV, Zafar A, Reynisson J, Nefedov AA, Volcho KP, Salakhutdinov NF, Lavrik OI. Aminoadamantanes containing monoterpene-derived fragments as potent tyrosyl-DNA phosphodiesterase 1 inhibitors. Bioorg Chem 2017; 76:392-399. [PMID: 29248742 DOI: 10.1016/j.bioorg.2017.12.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 11/28/2017] [Accepted: 12/01/2017] [Indexed: 12/17/2022]
Abstract
The ability of a number of nitrogen-containing compounds that simultaneously carry the adamantane and monoterpene moieties to inhibit Tdp1, an important enzyme of the DNA repair system, is studied. Inhibition of this enzyme has the potential to overcome chemotherapeutic resistance of some tumor types. Compound (+)-3c synthesized from 1-aminoadamantane and (+)-myrtenal, and compound 4a produced from 2-aminoadamantane and citronellal were found to be most potent as they inhibited Tdp1 with IC50 values of 6 and 3.5 µM, respectively. These compounds proved to have low cytotoxicity in colon HCT-116 and lung A-549 human tumor cell lines (CC50 > 50 µM). It was demonstrated that compound 4a at 10 µM enhanced cytotoxicity of topotecan, a topoisomerase 1 poison in clinical use, against HCT-116 more than fivefold and to a lesser extent of 1.5 increase in potency for A-549.
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Li Y, Zafar A, Kilmartin PA, Reynisson J, Leung IKH. Development and Application of an NMR-Based Assay for Polyphenol Oxidases. ChemistrySelect 2017. [DOI: 10.1002/slct.201702144] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Zafar A. 226 LCI correlation with FEV1, MMEF75-25 and RV/TLC for decline in airways function in CF children. J Cyst Fibros 2017. [DOI: 10.1016/s1569-1993(17)30571-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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79
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Zafar A, Seretis C, Feretis M, Karandikar S, Williams SC, Goldstein M, Chapman M. Comparative study of magnetic resonance defaecography and evacuation proctography in the evaluation of obstructed defaecation. Colorectal Dis 2017; 19:O204-O209. [PMID: 28304122 DOI: 10.1111/codi.13657] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Accepted: 02/13/2017] [Indexed: 12/13/2022]
Abstract
AIM Obstructed defaecation syndrome is a common condition of multifactorial aetiology and requires specialized evaluation. Accurate and reproducible pelvic floor imaging is imperative for multidisciplinary decision-making. Evacuation proctography (EP) and magnetic resonance defaecography (MRD) are the main imaging modalities used to assess dynamic pelvic floor function. The aim of this prospective study was to compare the findings and acceptability of MRD and EP in the same cohort of patients. METHOD This was a prospective comparative study of MRD vs EP in 55 patients with obstructed defaecation syndrome in a single National Health Service Foundation Trust. RESULTS Fifty-five patients were recruited and underwent both EP and MRD. Detection rates for rectocoele were similar (82% vs 73%, P = 0.227), but EP revealed a significantly higher number of trapping rectocoeles compared to MRD (75% vs 31%, P < 0.001). EP detected more rectal intussusceptions than MRD (56% vs 35%, P = 0.023). MRD appeared to underestimate the size of the identified rectocoele, although it detected a significant number of anatomical abnormalities in the middle and anterior pelvic compartment not seen on EP (1.8% enterocoele, 9% peritoneocoele and 20% cystocoele). Patients achieved higher rates of expulsion of rectal contrast during EP compared to MRD, but this difference was not significant (76% vs 64% in MRD, P = 0.092). Of the two studies, patients preferred MRD. CONCLUSIONS MRD provides a global assessment of pelvic floor function and anatomical abnormality. MRD is better tolerated by patients but it is not as sensitive as EP in detecting trapping rectocoeles and intussusceptions.
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Javaid A, Hasan R, Zafar A, Chaudry MA, Qayyum S, Qadeer E, Shaheen Z, Agha N, Rizvi N, Afridi MZ, Chima MK, Khan AR, Ghafoor A, Khan S, Awan SR, Akhtar S, Choudry K, Iqbal ZH, Ansarie M, Ahmad N. Pattern of first- and second-line drug resistance among pulmonary tuberculosis retreatment cases in Pakistan. Int J Tuberc Lung Dis 2017; 21:303-308. [PMID: 28225340 DOI: 10.5588/ijtld.16.0444] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Drug resistance in general, and multidrug-resistant tuberculosis (MDR-TB) in particular, threatens global tuberculosis (TB) control efforts. Population-based estimates of drug resistance are needed to develop strategies for controlling drug-resistant TB in Pakistan. OBJECTIVE To obtain population-based data on Mycobacterium tuberculosis drug resistance in Pakistan. METHODS To obtain drug resistance data, we conducted a population-based study of TB cases in all provinces of Pakistan. We performed culture and drug susceptibility testing on M. tuberculosis isolates from patients with a prior history of anti-tuberculosis treatment (retreatment cases) from all over the country. RESULTS Of 544 isolates from previously treated cases, 289 (53.1%) were susceptible to all first-line drugs, 255 (46.9%) were resistant to at least one anti-tuberculosis drug and 132 (24.3%) were MDR-TB. Among MDR-TB isolates, 47.0% were ofloxacin (OFX) resistant. Extensively drug-resistant TB was found in two (0.4%) isolates. CONCLUSION Prevalence of drug resistance in retreatment isolates was high. The alarmingly high prevalence of OFX resistance among MDR-TB isolates may threaten the success of efforts to control and treat MDR-TB.
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Zheng T, Wu ZT, Nan HY, Yu YF, Zafar A, Yan ZZ, Lu JP, Ni ZH. Layer-number dependent and structural defect related optical properties of InSe. RSC Adv 2017. [DOI: 10.1039/c7ra09370e] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We present systematic investigations on the layer-dependent optical properties of InSe and modify its excitonic states by electron beam irradiation.
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Zafar A, Hasan R, Nizamuddin S, Mahmood N, Mukhtar S, Ali F, Morrissey I, Barker K, Torumkuney D. Antibiotic susceptibility in Streptococcus pneumoniae, Haemophilus influenzae and Streptococcus pyogenes in Pakistan: a review of results from the Survey of Antibiotic Resistance (SOAR) 2002-15. J Antimicrob Chemother 2016; 71 Suppl 1:i103-9. [PMID: 27048578 DOI: 10.1093/jac/dkw076] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES To investigate changes in the antibiotic susceptibility of Streptococcus pneumoniae, Haemophilus influenzae and Streptococcus pyogenes from the Survey of Antibiotic Resistance (SOAR) in community-acquired respiratory tract infections (CA-RTIs) between 2002 and 2015 in Pakistan. METHODS This is a review based on previously published studies from 2002-03, 2004-06 and 2007-09 and also new data from 2014-15. Susceptibility was determined by Etest(®) or disc diffusion according to CLSI and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. RESULTS A total of 706 isolates from CA-RTIs comprising 381 S. pneumoniae, 230 H. influenzae and 95 S. pyogenes were collected between 2002 and 2015 and tested against a range of antibiotics. Antibiotic resistance in S. pneumoniae rose steeply from 2002 to 2009, with isolates non-susceptible to penicillin and macrolides increasing from 10% to 34.1% and from 13%-14% to 29.7%, respectively. Susceptibility to amoxicillin/clavulanic acid (and by inference amoxicillin) remained between 99.4% and 100% from 2002 to 2015. Over the years, the prevalence of susceptibility to cefuroxime was 98%-100% among S. pneumoniae. Resistance in S. pneumoniae to some older antibiotics between 2007 and 2009 was high (86.8% for trimethoprim/sulfamethoxazole and 57.2% for tetracycline). Between 2002 and 2015, ampicillin resistance (β-lactamase-positive strains) among H. influenzae has remained low (between 2.6% and 3.2%) and almost unchanged over the years (H. influenzae was not tested during 2004-06). For S. pyogenes isolates, macrolide resistance reached 22%; however, susceptibility to penicillin, amoxicillin/clavulanic acid and cefuroxime remained stable at 100%. CONCLUSIONS In S. pneumoniae from Pakistan, there has been a clear reduction in susceptibility to key antibiotics since 2002, but not to amoxicillin/clavulanic acid (amoxicillin) or cefuroxime. However, susceptibility in H. influenzae has remained stable. Local antibiotic susceptibility/resistance data are essential to support informed prescribing for CA-RTIs and other infections.
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Jadoon N, Hussain M, Sulehri F, Zafar A, Ijaz A. 82P Risk factors for breast cancer: A case-control study among post-menopausal women in Pakistan. Ann Oncol 2016. [DOI: 10.1093/annonc/mdw575.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Jadoon N, Hussain M, Sulehri F, Zafar A, Ijaz A. 82P Risk factors for breast cancer: A case-control study among post-menopausal women in Pakistan. Ann Oncol 2016. [DOI: 10.1016/s0923-7534(21)00242-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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85
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Zahid M, Arshad A, Zafar A, Al-Mohannadi D. Intracranial venous thrombosis in a man taking clomiphene citrate. BMJ Case Rep 2016; 2016:bcr2016217403. [PMID: 27873748 PMCID: PMC5128985 DOI: 10.1136/bcr-2016-217403] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/23/2016] [Indexed: 02/02/2023] Open
Abstract
Clomiphene citrate is widely used by the female population for the management of a wide array of medical conditions especially those related to ovulation, but its use in male population remains controversial. Efficacy of clomiphene is not well established in male hypogonadism and infertility. Its side effects and complications are also poorly studied or reported. We present a case of a man with infertility issues for which he started receiving clomiphene citrate 3 weeks before presenting with progressive symptoms of headache, vomiting, transient blurred vision and diplopia, which eventually turned out to be the symptoms of intracranial venous thrombosis. After excluding the common causes of intracranial venous thrombosis and hypercoagulable state, clomiphene citrate seems the most likely culprit.
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Martin EH, Zafar A, Caughman JBO, Isler RC, Bell GL. Applications of Doppler-free saturation spectroscopy for edge physics studies (invited). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:11E402. [PMID: 27910367 DOI: 10.1063/1.4961287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Doppler-free saturation spectroscopy provides a very powerful method to obtain detailed information about the electronic structure of the atom through measurement of the spectral line profile. This is achieved through a significant decrease in the Doppler broadening and essentially an elimination of the instrument broadening inherent to passive spectroscopic techniques. In this paper we present the technique and associated physics of Doppler-free saturation spectroscopy in addition to how one selects the appropriate transition. Simulations of Hδ spectra are presented to illustrate the increased sensitivity to both electric field and electron density measurements.
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Zafar A, Martin EH, Shannon SC, Isler RC, Caughman JBO. A temporally and spatially resolved electron density diagnostic method for the edge plasma based on Stark broadening. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:11E505. [PMID: 27910427 DOI: 10.1063/1.4955484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
An electron density diagnostic (≥1010 cm-3) capable of high temporal (ms) and spatial (mm) resolution is currently under development at Oak Ridge National Laboratory. The diagnostic is based on measuring the Stark broadened, Doppler-free spectral line profile of the n = 6-2 hydrogen Balmer series transition. The profile is then fit to a fully quantum mechanical model including the appropriate electric and magnetic field operators. The quasi-static approach used to calculate the Doppler-free spectral line profile is outlined here and the results from the model are presented for H-δ spectra for electron densities of 1010-1013 cm-3. The profile shows complex behavior due to the interaction between the magnetic substates of the atom.
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Khunti K, Gillies CL, Dallosso H, Brady EM, Gray LJ, Kilgallen G, Willis A, Zafar A, Davies MJ. Assessment of response rates and yields for Two opportunistic Tools for Early detection of Non-diabetic hyperglycaemia and Diabetes (ATTEND). A randomised controlled trial and cost-effectiveness analysis. Diabetes Res Clin Pract 2016; 118:12-20. [PMID: 27485852 DOI: 10.1016/j.diabres.2016.04.054] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 04/28/2016] [Accepted: 04/30/2016] [Indexed: 01/09/2023]
Abstract
AIMS To assess the opportunistic use in primary care of a computer risk score versus a self-assessment risk score for undiagnosed type 2 diabetes. METHODS We conducted a randomised controlled trial in 11 primary care practices in the UK. 577 patients aged 40-75years with no current diagnosis of type 2 diabetes were recruited to a computer based risk score (Leicester Practice Computer Risk Score (LPCRS)) or a patient self-assessment score (Leicester Self-Assessment Score (LSAS)). RESULTS The rate of self-referral blood tests was significantly higher for the LPCRS compared to the LSAS, 118.98 (95% CI: 102.85, 137.64) per 1000 high-risk patient years of follow-up compared to 92.14 (95% CI: 78.25, 108.49), p=0.022. Combined rate of diagnosis of type 2 diabetes and those at risk of developing the disease (i.e. impaired glucose tolerance (IGT) or impaired fasting glucose (IFG)) was similar between the two arms, 15.12 (95% CI: 9.11, 25.08) per 1000 high-risk patient years for LPCRS compared to 14.72 (95% CI: 9.59, 22.57) for the LSAS, p=0.699. For the base case scenario the cost per new case of type 2 diabetes diagnosed was lower for the LPCRS compared to the LSAS, £168 (95% Credible Interval (CrI): 76, 364), and £352 (95% CrI: 109, 1148), respectively. CONCLUSIONS Compared to a self-assessment risk score, a computer based risk score resulted in greater attendance to an initial blood test and is potentially more cost-effective.
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Zafar A, Reynisson J. Hydration Free Energy as a Molecular Descriptor in Drug Design: A Feasibility Study. Mol Inform 2016; 35:207-14. [PMID: 27492087 DOI: 10.1002/minf.201501035] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 03/11/2016] [Indexed: 01/29/2023]
Abstract
In this work the idea was investigated whether calculated hydration energy (ΔGhyd ) can be used as a molecular descriptor in defining promising regions of chemical space for drug design. Calculating ΔGhyd using the Density Solvation Model (SMD) in conjunction with the density functional theory (DFT) gave an excellent correlation with experimental values. Furthermore, calculated ΔGhyd correlates reasonably well with experimental water solubility (r(2) =0.545) and also log P (r(2) =0.530). Three compound collections were used: Known drugs (n=150), drug-like compounds (n=100) and simple organic compounds (n=140). As an approximation only molecules, which do not de/protonate at physiological pH were considered. A relatively broad distribution was seen for the known drugs with an average at -15.3 kcal/mol and a standard deviation of 7.5 kcal/mol. Interestingly, much lower averages were found for the drug-like compounds (-7.5 kcal/mol) and the simple organic compounds (-3.1 kcal/mol) with tighter distributions; 4.3 and 3.2 kcal/mol, respectively. This trend was not observed for these collections when calculated log P and log S values were used. The considerable greater exothermic ΔGhyd average for the known drugs clearly indicates in order to develop a successful drug candidate value of ΔGhyd <-5 kcal/mol or less is preferable.
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Hardy K, Wu F, Tu W, Zafar A, Boulding T, McCuaig R, Sutton CR, Theodoratos A, Rao S. Identification of chromatin accessibility domains in human breast cancer stem cells. Nucleus 2016; 7:50-67. [PMID: 26962893 PMCID: PMC4916893 DOI: 10.1080/19491034.2016.1150392] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Epithelial-to-mesenchymal transition (EMT) is physiological in embryogenesis and wound healing but also associated with the formation of cancer stem cells (CSCs). Many EMT signaling pathways are implicated in CSC formation, but the precise underlying mechanisms of CSC formation remain elusive. We have previously demonstrated that PKC is critical for EMT induction and CSC formation in inducible breast EMT/CSC models. Here, we used formaldehyde-assisted isolation of regulatory elements-sequencing (FAIRE-seq) to investigate DNA accessibility changes after PKC activation and determine how they influence EMT and CSC formation. During EMT, DNA accessibility principally increased in regions distant from transcription start sites, low in CpG content, and enriched with chromatin enhancer marks. ChIP-sequencing revealed that a subset of these regions changed from poised to active enhancers upon stimulation, with some even more acteylated in CSCs. While regions with increased accessibility were enriched for FOX, AP-1, TEAD, and TFAP2 motifs, those containing FOX and AP-1 motif were associated with increased expression of CSC-associated genes, while those with TFAP2 were associated with genes with increased expression in non-CSCs. Silencing of 2 members of the FOX family, FOXN2 and FOXQ1, repressed CSCs and the mesenchymal phenotype and inhibited the CSC gene signature. These novel, PKC-induced DNA accessibility regions help explain how the epigenomic plasticity of cells undergoing EMT leads to CSC gene activation.
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Zafar A, Williamson M. P46 Dextrocardia and right atrial isomerism associated with congenital trifurcation of trachea. BRITISH HEART JOURNAL 2016. [DOI: 10.1136/heartjnl-2016-309377.46] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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92
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Boyle E, Gowey A, Zafar A, Burke P, Kavanagh E, Abdulrahim O. Vascular Trauma – Unusual Mechanisms of Injury. Eur J Vasc Endovasc Surg 2015. [DOI: 10.1016/j.ejvs.2015.06.094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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93
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Manzoor SA, Mirza SN, Zubair M, Nouman W, Hussain SB, Mehmood S, Irshad A, Sarwar N, Ammar A, Iqbal MF, Asim A, Chattha MU, Chattha MB, Zafar A, Abid R. Estimating genetic potential of biofuel forest hardwoods to withstand metal toxicity in industrial effluent under dry tropical conditions. GENETICS AND MOLECULAR RESEARCH 2015; 14:9543-54. [PMID: 26345887 DOI: 10.4238/2015.august.14.17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Biofuel tree species are recognized as a promising alternative source of fuel to conventional forms. Additionally, these tree species are also effective in accumulating toxic heavy metals present in some industrial effluents. In developing countries such as Pakistan, the use of biofuel tree species is gaining popularity not only for harvesting economical and environmentally friendly biofuel, but also to sequester poisonous heavy metals from industrial wastewater. This study was aimed at evaluating the genetic potential of two biofuel species, namely, Jatropha curcas and Pongamia pinnata, to grow when irrigated with industrial effluent from the Pak-Arab Fertilizer Factory Multan, Southern Punjab, Pakistan. The growth performances of one-year-old seedlings of both species were compared in soil with adverse physiochemical properties. It was found that J. curcas was better able to withstand the toxicity of the heavy metals present in the fertilizer factory effluent. J. curcas showed maximum gain in height, diameter, and biomass production in soil irrigated with 75% concentrated industrial effluent. In contrast, P. pinnata showed a significant reduction in growth in soil irrigated with more than 50% concentrated industrial effluent, indicating that this species is less tolerant to higher toxicity levels of industrial effluent. This study identifies J. curcas as a promising biofuel tree species that can be grown using industrial wastewater.
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94
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Zafar A, Stone MA, Davies MJ, Khunti K. Acknowledging and allocating responsibility for clinical inertia in the management of Type 2 diabetes in primary care: a qualitative study. Diabet Med 2015; 32:407-13. [PMID: 25251768 DOI: 10.1111/dme.12592] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/10/2014] [Indexed: 12/29/2022]
Abstract
AIMS Failure to intensify treatment in patients with Type 2 diabetes with suboptimal blood glucose control has been termed clinical inertia and has been shown to contribute to poorer patient outcomes. We aimed to identify and explore perceptions about clinical inertia from the perspective of primary healthcare providers. METHODS A qualitative study was conducted in Leicestershire and Northamptonshire, UK. Purposive sampling was based on healthcare providers working in primary care settings with 'higher' and 'lower' target achievement based on routine data. Twenty semi-structured interviews were conducted, face-to-face or by telephone. Thematic analysis was informed by the constant comparative approach. RESULTS An important broad theme that emerged during the analysis was related to attribution and explanation of responsibility for clinical inertia. This included general willingness to accept a degree of responsibility for clinical inertia. In some cases, however, participants had inaccurate perceptions about levels of target achievement in their primary care centres, as indicated by routine data. Participants sought to lessen their own sense of accountability by highlighting patient-level barriers such as comorbidities and human fallibility, and also system-level barriers, particularly time constraints. Perceptions about ways of addressing the problem of clinical inertia were not seen as straightforward, further emphasizing a complex and cumulative pattern of barriers. CONCLUSIONS In order to understand and address the problem of clinical inertia, provider, patient- and system-level barriers should be considered together rather than as separate issues. Acknowledgement of responsibility should be regarded positively as a motivator for change.
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Ul-ain B, Zafar A, Ahmed S. To explore a new class of material (X-type hexaferrites) for N2O decomposition. Catal Sci Technol 2015. [DOI: 10.1039/c4cy00964a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Monophasic X-type Mn- and Cr-doped Ba–Co ferrites, synthesized by co-precipitation, catalytically decomposed N2O gas while remaining stable at 1000 K.
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Sayal P, Zafar A, Ramsewak S, Yousefpour A. Reconstructive Techniques in Skull Base Surgery for Head and Neck Malignancies. Skull Base Surg 2014. [DOI: 10.1055/s-0034-1384090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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97
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Musani SA, Essani RR, Khowaja RM, Alwani NR, Lakhani S, Zafar A. P286: Decreasing nosocomial exposures of tuberculosis to healthcare workers at emergency department in a tertiary care hospital in Karachi, Pakistan. Antimicrob Resist Infect Control 2013. [PMCID: PMC3688037 DOI: 10.1186/2047-2994-2-s1-p286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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98
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Zafar A, Schjødt-Thomsen J, Sodhi R, Goacher R, de Kubber D. Investigation of the ageing effects on phenol-urea-formaldehyde binder and alkanol amine-acid anhydride binder coated mineral fibres. Polym Degrad Stab 2013. [DOI: 10.1016/j.polymdegradstab.2012.09.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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99
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Irfan S, Ahmad A, Guhar D, Khan E, Malik F, Mahmood S, Zafar A. Fluoroquinolone and macrolide co-resistance in clinical isolates of Campylobacter species: a 15-year study in Karachi, Pakistan. EASTERN MEDITERRANEAN HEALTH JOURNAL 2012; 16:1226-30. [PMID: 24988396 DOI: 10.26719/2010.16.12.1226] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Accepted: 03/05/2009] [Indexed: 11/09/2022]
Abstract
Fluoroquinolone and macrolide antibiotics are generally considered as first-line drugs for the treatment of severe campylobacteriosis. This study was conducted to analyse the trend of erythromycin and ofloxacin resistance among Campylobacter spp. isolated from stool specimens over a period of 15 years (1992-2007) at The Aga Khan University clinical laboratory in Karachi, Pakistan. A total of 83 396 stool specimens were processed, with a 14% isolation rate for enteric pathogens. The isolation rate of Campylobacter spp. was low during 1992-93 (6%-13%), peaked in 1996 (46%), then ranged from 20% to 40%. We report a rising trend in ofloxacin resistance, re-emergence of erythromycin resistance and indications of co-resistance to both drugs in clinical isolates of Campylobacter spp.
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Maimaiti N, Zafar A, Amrizal M, Zaleha MI, Saperi S, Aljunid S. Estimating clinical and economic burden of pneumococcal meningitis in Malaysia using Casemix data. BMC Health Serv Res 2012. [PMCID: PMC3503585 DOI: 10.1186/1472-6963-12-s1-o4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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