Adnan Khan - Academia.edu (original) (raw)

Papers by Adnan Khan

Rapid and accurate identification of bacterial pathogens is a fundamental goal of clinical microb... more Rapid and accurate identification of bacterial pathogens is a fundamental goal of clinical microbiology. The diagnosis and surveillance of diseases is dependent, to a great extent, on laboratory services, which cannot function without effective reliable reagents and diagnostics. Despite the advancement in microbiology diagnosis globally, resourcelimited countries still struggle to provide an acceptable diagnosis quality which helps in clinical disease management and improve their mortality and morbidity data. During this study an indigenous product, Quick Test Strip (QTS) NE, was developed for the rapid identification of biochemically slower group of Gram-negative oxidase-positive bacilli that covers 19 different bacterial genera. Some of the members belonging to these groups are well-established human pathogens, e.g. various species of Vibrio, Pseudomonas, Burkholderia, Aeromonas, Achromobacter and Stenotrophomonas. This study also evaluates the performance of QTS-NE by comparing with genotypic characterization methods. A total of 232 clinical and reference bacterial isolates were tested by three different methods. QTS-NE provides 100% concordant results with other rapid identification and molecular characterization methods and confirms the potential to be used in clinical diagnosis.

In Pakistan, clean drinking water is not available to most of the population. Main source of drin... more In Pakistan, clean drinking water is not available to most of the population. Main source of drinking water in Hazara, Azad Jammu and Kashmir-Pakistan is underground and spring water, due to earthquake water reservoirs in these areas were immensely contaminated. Moreover, drinking water treatment and proper sanitary facilities were also lacking. This study was conducted to analyze the quality of drinking water available in most of the cities of Pakistan including earthquake hit areas. For this purpose, 112 water samples were collected and analyzed by membrane filtration method. Microbial isolates were identified using QTS-10 and biochemical tests. Almost all samples were found to be contaminated but in earthquake affected areas quality of drinking water was substandard than other areas of Pakistan. Results revealed the detection of following bacterial pathogens among the water samples: Enterobacter sp., Klebsiella sp., Stenotrophomonas sp., Salmonella sp., Proteus sp., Edwardsiella tarda, Pseudomonas aeruginosa, Vibrio parahaemolyticus, Vibrio cholerae, Escherichia coli, Acinetobacter baumanii, Aeromonas hydrophila, Citrobacter freundii, Shigella dysenteriae, Staphylococcus aureus, Staphylococcus sp. and Streptococcus sp. Furthermore, these bacterial isolates were found to be resistant to ampicillin (32.1%), amoxicillin (30.4%), sulphometoxazole (20.5%) and cefaclor (31.3%). All drinking water samples were analyzed for 16S rRNA gene of Helicobacter pylori by using PCR, however no positive result was found in these samples. Based on our results it is suggested that authorities should pay attention to supply safe water and proper sanitary facilities to avoid epidemics of infectious diseases in future.

Background: Prevalence of Helicobacter pylori (H. pylori) infection is an increasing problem in d... more Background: Prevalence of Helicobacter pylori (H. pylori) infection is an increasing problem in developing countries. Several environmental factors such as overcrowding, poverty, contaminated drinking water and food are considered to contribute toward transmission of infection; however, little is known about their definitive roles. The aim of this study is to investigate the presence of H. pylori in drinking water samples of Karachi, Pakistan. Methodology: Samples of drinking water were collected from 18 different towns located in the metropolitan area of Karachi. Samples were concentrated by membrane filtration method and subjected to PCR for the detection of H. pylori. Results: Two out of 50 (4%) samples collected from two different densely populated town areas were found to be positive for H. pylori. Conclusion: The study provides evidence for the presence of H. pylori in municipal drinking water of Karachi.

To determine antibiotic resistance o� Helicobacter pylori (H. pylori ) in �akistan and its correl... more To determine antibiotic resistance o� Helicobacter pylori (H. pylori ) in �akistan and its correlation with host and pathogen associated �actors.

PloS one, 2015

Synergistic combinations of antimicrobial agents with different mechanisms of action have been in... more Synergistic combinations of antimicrobial agents with different mechanisms of action have been introduced as more successful strategies to combat infections involving multidrug resistant (MDR) bacteria. In this study, we investigated synergistic antimicrobial activity of Camellia sinensis and Juglans regia which are commonly used plants with different antimicrobial agents. Antimicrobial susceptibility of 350 Gram-positive and Gram-negative strains belonging to 10 different bacterial species, was tested against Camellia sinensis and Juglans regia extracts. Minimum inhibitory concentrations (MICs) were determined by agar dilution and microbroth dilution assays. Plant extracts were tested for synergistic antimicrobial activity with different antimicrobial agents by checkerboard titration, Etest/agar incorporation assays, and time kill kinetics. Extract treated and untreated bacteria were subjected to transmission electron microscopy to see the effect on bacterial cell morphology. Camellia sinensis extract showed higher antibacterial activity against MDR S. Typhi, alone and in combination with nalidixic acid, than to susceptible isolates." We further explore anti-staphylococcal activity of Juglans regia that lead to the changes in bacterial cell morphology indicating the cell wall of Gram-positive bacteria as possible target of action. The synergistic combination of Juglans regia and oxacillin reverted oxacillin resistance of methicillin resistant Staphylococcus aureus (MRSA) strains in vitro. This study provides novel information about antimicrobial and synergistic activity of Camellia sinensis and Juglans regia against MDR pathogens PLOS ONE |

The Routledge Companion to International Management Education, 2011

International Conference on Emerging Technologies, 2005

Multiple access interference (MAI) is the most significant limiting factor on the capacity of the... more Multiple access interference (MAI) is the most significant limiting factor on the capacity of the conventional DS-CDMA systems. In this paper an analysis of the character of MAI is carried out. The main causes of intra-cell MAI and their effects on the system are highlighted through simulation and analysis. A considerable research effort in the development of efficient multiple user detection (MUD) techniques is in progress, however no concrete analysis of MAI and its character modeling is found in the literature. In aim paper numerous factors which result in MAI enhancement like asynchronous reverse channel, semi-orthogonal long PN codes and increase in users are analyzed. This quantification of MAI character result in its clearer understanding and leads to a more realistic and efficient MOD algorithms

International Conference on Emerging Technologies, 2007

Page 1. Spatial Multiplexing System with Orthogonal Data Streams IKhawaja Tauseef Tasneem, 2Adnan... more Page 1. Spatial Multiplexing System with Orthogonal Data Streams IKhawaja Tauseef Tasneem, 2Adnan Ahmed Khan, 2Sajid Bashir, 'Syed Ismail Shah, Sr. MIEEE lIqraUniversity Islamabad Campus, Islamabad, Pakistan 2Centre for Advanced Studies in Engineering, Pakistan ...

Chemical Engineering Journal, 2011

The biopolymer chitosan was chemically modified in a two step reaction with glycidylmethacrylate ... more The biopolymer chitosan was chemically modified in a two step reaction with glycidylmethacrylate and diethylenetriamine. The first step leads to the opening of the three-member epoxide ring of glycidylmethacrylate, leaving a double a bond for further reaction. This product reacted with diethylenetriamine through the free glycidylmethacrylate double bond in a second step. The chemically modified biopolymer was characterized by elemental analysis, IR, 13C NMR, TG, SEM and employed for copper, lead and cadmium biosorption. Elemental analysis data based on nitrogen atom content gave an incorporation of 4.89 mmol of organic pendant groups for each gram of the biopolymer. Nuclear magnetic resonance of the carbon nucleus in the solid state and infrared spectroscopies are in agreement with the success of the proposed chemical modification, while the TG curve demonstrated that the final product is less stable than the precursor biopolymer. The increment of basic centers attached to the pendant chains showed that the metal sorption capability of the final chelating material was higher than chitosan, presenting cation sorptions from aqueous solution in the order Cu2+ > Pb2+ > Cd2+. The experimental data were adjusted to the Langmuir, the Freundlich and the Temkin sorption isotherm models. The behavior suggested that this new modified biopolymer could be employed as a promising sorbent for cation removal from polluted systems.

The Journal of the Arkansas Medical Society, 2004

JPMA. The Journal of the Pakistan Medical Association, 2009

Objective: To estimate the frequency of Sexually Transmitted Infections (STIs) among sex workers ... more Objective: To estimate the frequency of Sexually Transmitted Infections (STIs) among sex workers and drug users in Pakistan. Methods: Interviews were conducted on 3640 sex workers, injection drug users and truckers about STI symptoms within the past year and currently and the care they sought for them. Results: Nearly half (46%) reported STI symptoms in the past 12 months and 55% went for treatment. Most of the care sought was from the private sector and more by IDUs and female sex workers. Increasing age or having a genital ulcer predicted care seeking.

Colloids and surfaces. B, Biointerfaces, 2011

The biopolymer chitosan was chemically modified with dithiocarbamate, characterized by elemental ... more The biopolymer chitosan was chemically modified with dithiocarbamate, characterized by elemental analysis, IR, 13 C NMR and TG, and applied for lead, copper and cadmium removal. Based on sulfur elemental analysis an amount of 2.66 mmol g −1 of pendant chain was incorporated in the original biopolymer, as also demonstrated through the appearance of a signal at 201 ppm in the 13 C NMR in the solid state. The TG curve demonstrated that the final product is more stable than the precursor chitosan. The sorption capacity of modified biopolymer was determined through a batchwise methodology, with maximum capacities of 2.24; 1.14 and 0.84 mmol g −1 for divalent lead, copper and cadmium from aqueous solution, respectively. The highest sorption capacity for lead reflects the soft cation/sulfur interaction. The experimental data were adjusted to the Langmuir, the Freundlich and the Temkin sorption isotherm models using both linear and nonlinear regression analysis.

European journal of immunology, 2013

Dendritic cell (DC) modification is a potential strategy to induce clinical transplantation toler... more Dendritic cell (DC) modification is a potential strategy to induce clinical transplantation tolerance. We compared two DC modification strategies to inhibit allogeneic T-cell proliferation. In the first strategy, murine DCs were transduced with a lentiviral vector expressing CTLA4-KDEL, a fusion protein that prevents surface CD80/86 expression by retaining the co-stimulatory molecules within the ER. In the second approach, DCs were transduced to express the tryptophan-catabolising enzyme IDO. CTLA4-KDEL-expressing DCs induced anergy in alloreactive T cells and generated both CD4 + CD25 + and CD4 + CD25 −

JPMA. The Journal of the Pakistan Medical Association, 2013

Introduction: With the contraceptive prevalence rate (CPR) at 30% in 2006-7, the rates of contrac... more Introduction: With the contraceptive prevalence rate (CPR) at 30% in 2006-7, the rates of contraception use among married women of reproductive age (MWRA) in Pakistan are among the lowest in the region. This paper explores some options of unmet need as a means of addressing the low CPR.

JPMA. The Journal of the Pakistan Medical Association, 2013

The public sector provides a third of family planning (FP) services in Pakistan. However, these s... more The public sector provides a third of family planning (FP) services in Pakistan. However, these services are viewed as being underutilized and expensive. We explored the utilization patterns and costs of FP services in the public sector.

JPMA. The Journal of the Pakistan Medical Association, 2013

Community-based distribution (CBD) has been successfully applied to family planning (FP) services... more Community-based distribution (CBD) has been successfully applied to family planning (FP) services worldwide. It forms the basis for the large lady health worker (LHW) programme in Pakistan which serves a limited number of women with contraception services. Thus, the concept has seen limited application in Pakistan. We present the outcomes of a CBD model that was implemented in 49 districts across Pakistan by a non-government organization (NGO).

Frontiers in neurology, 2014

† Nermin Serbecic and Fahmy Aboul-Enein have contributed equally to this work.

Rapid and accurate identification of bacterial pathogens is a fundamental goal of clinical microb... more Rapid and accurate identification of bacterial pathogens is a fundamental goal of clinical microbiology. The diagnosis and surveillance of diseases is dependent, to a great extent, on laboratory services, which cannot function without effective reliable reagents and diagnostics. Despite the advancement in microbiology diagnosis globally, resourcelimited countries still struggle to provide an acceptable diagnosis quality which helps in clinical disease management and improve their mortality and morbidity data. During this study an indigenous product, Quick Test Strip (QTS) NE, was developed for the rapid identification of biochemically slower group of Gram-negative oxidase-positive bacilli that covers 19 different bacterial genera. Some of the members belonging to these groups are well-established human pathogens, e.g. various species of Vibrio, Pseudomonas, Burkholderia, Aeromonas, Achromobacter and Stenotrophomonas. This study also evaluates the performance of QTS-NE by comparing with genotypic characterization methods. A total of 232 clinical and reference bacterial isolates were tested by three different methods. QTS-NE provides 100% concordant results with other rapid identification and molecular characterization methods and confirms the potential to be used in clinical diagnosis.

In Pakistan, clean drinking water is not available to most of the population. Main source of drin... more In Pakistan, clean drinking water is not available to most of the population. Main source of drinking water in Hazara, Azad Jammu and Kashmir-Pakistan is underground and spring water, due to earthquake water reservoirs in these areas were immensely contaminated. Moreover, drinking water treatment and proper sanitary facilities were also lacking. This study was conducted to analyze the quality of drinking water available in most of the cities of Pakistan including earthquake hit areas. For this purpose, 112 water samples were collected and analyzed by membrane filtration method. Microbial isolates were identified using QTS-10 and biochemical tests. Almost all samples were found to be contaminated but in earthquake affected areas quality of drinking water was substandard than other areas of Pakistan. Results revealed the detection of following bacterial pathogens among the water samples: Enterobacter sp., Klebsiella sp., Stenotrophomonas sp., Salmonella sp., Proteus sp., Edwardsiella tarda, Pseudomonas aeruginosa, Vibrio parahaemolyticus, Vibrio cholerae, Escherichia coli, Acinetobacter baumanii, Aeromonas hydrophila, Citrobacter freundii, Shigella dysenteriae, Staphylococcus aureus, Staphylococcus sp. and Streptococcus sp. Furthermore, these bacterial isolates were found to be resistant to ampicillin (32.1%), amoxicillin (30.4%), sulphometoxazole (20.5%) and cefaclor (31.3%). All drinking water samples were analyzed for 16S rRNA gene of Helicobacter pylori by using PCR, however no positive result was found in these samples. Based on our results it is suggested that authorities should pay attention to supply safe water and proper sanitary facilities to avoid epidemics of infectious diseases in future.

Background: Prevalence of Helicobacter pylori (H. pylori) infection is an increasing problem in d... more Background: Prevalence of Helicobacter pylori (H. pylori) infection is an increasing problem in developing countries. Several environmental factors such as overcrowding, poverty, contaminated drinking water and food are considered to contribute toward transmission of infection; however, little is known about their definitive roles. The aim of this study is to investigate the presence of H. pylori in drinking water samples of Karachi, Pakistan. Methodology: Samples of drinking water were collected from 18 different towns located in the metropolitan area of Karachi. Samples were concentrated by membrane filtration method and subjected to PCR for the detection of H. pylori. Results: Two out of 50 (4%) samples collected from two different densely populated town areas were found to be positive for H. pylori. Conclusion: The study provides evidence for the presence of H. pylori in municipal drinking water of Karachi.

To determine antibiotic resistance o� Helicobacter pylori (H. pylori ) in �akistan and its correl... more To determine antibiotic resistance o� Helicobacter pylori (H. pylori ) in �akistan and its correlation with host and pathogen associated �actors.

PloS one, 2015

Synergistic combinations of antimicrobial agents with different mechanisms of action have been in... more Synergistic combinations of antimicrobial agents with different mechanisms of action have been introduced as more successful strategies to combat infections involving multidrug resistant (MDR) bacteria. In this study, we investigated synergistic antimicrobial activity of Camellia sinensis and Juglans regia which are commonly used plants with different antimicrobial agents. Antimicrobial susceptibility of 350 Gram-positive and Gram-negative strains belonging to 10 different bacterial species, was tested against Camellia sinensis and Juglans regia extracts. Minimum inhibitory concentrations (MICs) were determined by agar dilution and microbroth dilution assays. Plant extracts were tested for synergistic antimicrobial activity with different antimicrobial agents by checkerboard titration, Etest/agar incorporation assays, and time kill kinetics. Extract treated and untreated bacteria were subjected to transmission electron microscopy to see the effect on bacterial cell morphology. Camellia sinensis extract showed higher antibacterial activity against MDR S. Typhi, alone and in combination with nalidixic acid, than to susceptible isolates." We further explore anti-staphylococcal activity of Juglans regia that lead to the changes in bacterial cell morphology indicating the cell wall of Gram-positive bacteria as possible target of action. The synergistic combination of Juglans regia and oxacillin reverted oxacillin resistance of methicillin resistant Staphylococcus aureus (MRSA) strains in vitro. This study provides novel information about antimicrobial and synergistic activity of Camellia sinensis and Juglans regia against MDR pathogens PLOS ONE |

The Routledge Companion to International Management Education, 2011

International Conference on Emerging Technologies, 2005

Multiple access interference (MAI) is the most significant limiting factor on the capacity of the... more Multiple access interference (MAI) is the most significant limiting factor on the capacity of the conventional DS-CDMA systems. In this paper an analysis of the character of MAI is carried out. The main causes of intra-cell MAI and their effects on the system are highlighted through simulation and analysis. A considerable research effort in the development of efficient multiple user detection (MUD) techniques is in progress, however no concrete analysis of MAI and its character modeling is found in the literature. In aim paper numerous factors which result in MAI enhancement like asynchronous reverse channel, semi-orthogonal long PN codes and increase in users are analyzed. This quantification of MAI character result in its clearer understanding and leads to a more realistic and efficient MOD algorithms

International Conference on Emerging Technologies, 2007

Page 1. Spatial Multiplexing System with Orthogonal Data Streams IKhawaja Tauseef Tasneem, 2Adnan... more Page 1. Spatial Multiplexing System with Orthogonal Data Streams IKhawaja Tauseef Tasneem, 2Adnan Ahmed Khan, 2Sajid Bashir, 'Syed Ismail Shah, Sr. MIEEE lIqraUniversity Islamabad Campus, Islamabad, Pakistan 2Centre for Advanced Studies in Engineering, Pakistan ...

Chemical Engineering Journal, 2011

The biopolymer chitosan was chemically modified in a two step reaction with glycidylmethacrylate ... more The biopolymer chitosan was chemically modified in a two step reaction with glycidylmethacrylate and diethylenetriamine. The first step leads to the opening of the three-member epoxide ring of glycidylmethacrylate, leaving a double a bond for further reaction. This product reacted with diethylenetriamine through the free glycidylmethacrylate double bond in a second step. The chemically modified biopolymer was characterized by elemental analysis, IR, 13C NMR, TG, SEM and employed for copper, lead and cadmium biosorption. Elemental analysis data based on nitrogen atom content gave an incorporation of 4.89 mmol of organic pendant groups for each gram of the biopolymer. Nuclear magnetic resonance of the carbon nucleus in the solid state and infrared spectroscopies are in agreement with the success of the proposed chemical modification, while the TG curve demonstrated that the final product is less stable than the precursor biopolymer. The increment of basic centers attached to the pendant chains showed that the metal sorption capability of the final chelating material was higher than chitosan, presenting cation sorptions from aqueous solution in the order Cu2+ > Pb2+ > Cd2+. The experimental data were adjusted to the Langmuir, the Freundlich and the Temkin sorption isotherm models. The behavior suggested that this new modified biopolymer could be employed as a promising sorbent for cation removal from polluted systems.

The Journal of the Arkansas Medical Society, 2004

JPMA. The Journal of the Pakistan Medical Association, 2009

Objective: To estimate the frequency of Sexually Transmitted Infections (STIs) among sex workers ... more Objective: To estimate the frequency of Sexually Transmitted Infections (STIs) among sex workers and drug users in Pakistan. Methods: Interviews were conducted on 3640 sex workers, injection drug users and truckers about STI symptoms within the past year and currently and the care they sought for them. Results: Nearly half (46%) reported STI symptoms in the past 12 months and 55% went for treatment. Most of the care sought was from the private sector and more by IDUs and female sex workers. Increasing age or having a genital ulcer predicted care seeking.

Colloids and surfaces. B, Biointerfaces, 2011

The biopolymer chitosan was chemically modified with dithiocarbamate, characterized by elemental ... more The biopolymer chitosan was chemically modified with dithiocarbamate, characterized by elemental analysis, IR, 13 C NMR and TG, and applied for lead, copper and cadmium removal. Based on sulfur elemental analysis an amount of 2.66 mmol g −1 of pendant chain was incorporated in the original biopolymer, as also demonstrated through the appearance of a signal at 201 ppm in the 13 C NMR in the solid state. The TG curve demonstrated that the final product is more stable than the precursor chitosan. The sorption capacity of modified biopolymer was determined through a batchwise methodology, with maximum capacities of 2.24; 1.14 and 0.84 mmol g −1 for divalent lead, copper and cadmium from aqueous solution, respectively. The highest sorption capacity for lead reflects the soft cation/sulfur interaction. The experimental data were adjusted to the Langmuir, the Freundlich and the Temkin sorption isotherm models using both linear and nonlinear regression analysis.

European journal of immunology, 2013

Dendritic cell (DC) modification is a potential strategy to induce clinical transplantation toler... more Dendritic cell (DC) modification is a potential strategy to induce clinical transplantation tolerance. We compared two DC modification strategies to inhibit allogeneic T-cell proliferation. In the first strategy, murine DCs were transduced with a lentiviral vector expressing CTLA4-KDEL, a fusion protein that prevents surface CD80/86 expression by retaining the co-stimulatory molecules within the ER. In the second approach, DCs were transduced to express the tryptophan-catabolising enzyme IDO. CTLA4-KDEL-expressing DCs induced anergy in alloreactive T cells and generated both CD4 + CD25 + and CD4 + CD25 −

JPMA. The Journal of the Pakistan Medical Association, 2013

Introduction: With the contraceptive prevalence rate (CPR) at 30% in 2006-7, the rates of contrac... more Introduction: With the contraceptive prevalence rate (CPR) at 30% in 2006-7, the rates of contraception use among married women of reproductive age (MWRA) in Pakistan are among the lowest in the region. This paper explores some options of unmet need as a means of addressing the low CPR.

JPMA. The Journal of the Pakistan Medical Association, 2013

The public sector provides a third of family planning (FP) services in Pakistan. However, these s... more The public sector provides a third of family planning (FP) services in Pakistan. However, these services are viewed as being underutilized and expensive. We explored the utilization patterns and costs of FP services in the public sector.

JPMA. The Journal of the Pakistan Medical Association, 2013

Community-based distribution (CBD) has been successfully applied to family planning (FP) services... more Community-based distribution (CBD) has been successfully applied to family planning (FP) services worldwide. It forms the basis for the large lady health worker (LHW) programme in Pakistan which serves a limited number of women with contraception services. Thus, the concept has seen limited application in Pakistan. We present the outcomes of a CBD model that was implemented in 49 districts across Pakistan by a non-government organization (NGO).

Frontiers in neurology, 2014

† Nermin Serbecic and Fahmy Aboul-Enein have contributed equally to this work.