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Peter Scott Reid - One of the best experts on this subject based on the ideXlab platform.
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concepts of illicit Drug Quality among darknet market users purity embodied experience craft and chemical knowledge
International Journal of Drug Policy, 2016Co-Authors: Angus Bancroft, Peter Scott ReidAbstract:Abstract Background Users of darknet markets refer to product Quality as one of the motivations for buying Drugs there, and vendors present Quality as a selling point. However, what users understand by Quality and how they evaluate it is not clear. This article investigates how users established and compared Drug Quality. Methods We used a two-stage method for investigating users’ assessments. The user forum of a darknet market that we called ‘Merkat’ was analysed to develop emergent themes. Qualitative interviews with darknet users were conducted, then forum data was analysed again. To enhance the applicability of the findings, the forum was sampled for users who presented as dependent as well as recreational. Results Quality could mean reliability, purity, potency, and predictability of effect. We focused on the different kinds of knowledge users drew on to assess Quality. These were: embodied; craft; and chemical. Conclusion Users’ evaluations of Quality depended on their experience, the purpose of use, and its context. Market forums are a case of indigenous harm reduction where users share advise and experiences and can be usefully engaged with on these terms.
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concepts of illicit Drug Quality among darknet market users purity embodied experience craft and chemical knowledge
Social Science Research Network, 2015Co-Authors: Angus Bancroft, Peter Scott ReidAbstract:Background: Users of darknet markets refer to product Quality as one of the motivations for buying Drugs there, and vendors present Quality as a selling point. However what users understand by Quality and how they evaluate it is not clear. This paper investigates how users established and compared Drug Quality. Methods: We used a two-stage method for investigating users' assessments. The user forum of a darknet market that we called 'Merkat' was analysed to develop emergent themes. Qualitative interviews with darknet users were conducted, then forum data was analysed again. To enhance the applicability of the findings, the forum was sampled for users who presented as dependent as well as recreational.Results: Quality could mean reliability, purity, potency, and predictability of effect. We focused on the different kinds of knowledge users drew on to assess Quality. These were: embodied; craft; and chemical. Conclusion: Users’ evaluations of Quality depended on their experience, the purpose of use, and its context. Market forums are a case of indigenous harm reduction where users share advise and experiences and can be usefully engaged with on these terms.Highlights:• We investigate how darknet market users assess Drug Quality• Market forums allow users to apply embodied, craft and chemical knowledge to compare the Quality of different products• Good Quality does not necessarily equate to high chemical purity• Different Drugs are assessed with different priorities in mindExpanding the range of knowledge types that users apply to product Quality may have positive implications for harm reduction.
Paul N. Newton - One of the best experts on this subject based on the ideXlab platform.
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counterfeit and substandard anti infectives in developing countries
2010Co-Authors: Facundo M Fernandez, Michael D. Green, Paul N. Newton, Joyce Primocarpenter, Nicholas J WhiteAbstract:There is considerable interest in optimizing the therapy for important infections in developing countries and in making the best treatments readily available and inexpensive. There is also great concern that resistance to anti-infective Drugs is worsening, putting affordable treatments at risk. We argue that an important, but usually neglected aspect of these problems is Drug Quality. Drugs may be of poor Quality if they are counterfeit, substandard or degraded. Few objective data on the prevalence of poor-Quality Drugs exist but surveys suggest that an alarming proportion of antimalarials and antibiotics in much of the developing world are of poor Quality. For individual patients these will increase mortality and morbidity and lead to loss of faith in medicines and health systems. Counterfeit, substandard or degraded Drugs with sub-therapeutic concentrations of the active ingredient or the wrong active ingredient are likely to engender the emergence and spread of resistance to these anti-infectives. Although modelling suggests that poor-Quality Drug should worsen Drug resistance, there is sparse evidence from the field, as there has been little research. It will be very difficult to distinguish the effects of poor-Drug Quality and reduced patient adherence and incorrect health worker prescribing on the spread of resistance. Strengthening Drug regulatory authorities, improving Quality of Drug production and facilitating the availability of relatively inexpensive, good-Quality anti-infectives are likely to be key factors in improving Drug Quality.
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assessment of hand held raman instrumentation for in situ screening for potentially counterfeit artesunate antimalarial tablets by ft raman spectroscopy and direct ionization mass spectrometry
Analytica Chimica Acta, 2008Co-Authors: Camilla Ricci, Facundo M Fernandez, Paul N. Newton, Leonard Nyadong, Felicia Yang, Christopher D Brown, Sergei G KazarianAbstract:Pharmaceutical counterfeiting has become a significant public health problem worldwide and new, rapid, user-friendly, reliable and inexpensive methods for Drug Quality screening are needed. This work illustrates the chemical characterization of genuine and fake artesunate antimalarial tablets by portable Raman spectroscopy and validation by FT-Raman spectroscopy and ambient mass spectrometry. The applicability of a compact and robust portable Raman spectrometer (TruScan™) for the in situ chemical identification of counterfeit tablets is reported.
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Use of refractometry and colorimetry as field methods to rapidly assess antimalarial Drug Quality
Journal of Pharmaceutical and Biomedical Analysis, 2007Co-Authors: Michael D. Green, Henry Nettey, Ofelia Villalva Rojas, Chansapha Pamanivong, Lamphet Khounsaknalath, Miguel Grande Ortiz, Latsamy Vongsack, Facundo M Fernandez, Paul N. Newton, Ot ManolinAbstract:The proliferation of counterfeit and poor-Quality Drugs is a major public health problem; especially in developing countries lacking adequate resources to effectively monitor their prevalence. Simple and affordable field methods provide a practical means of rapidly monitoring Drug Quality in circumstances where more advanced techniques are not available. Therefore, we have evaluated refractometry, colorimetry and a technique combining both processes as simple and accurate field assays to rapidly test the Quality of the commonly available antimalarial Drugs; artesunate, chloroquine, quinine, and sulfadoxine. Method bias, sensitivity, specificity and accuracy relative to high-performance liquid chromatographic (HPLC) analysis of Drugs collected in the Lao PDR were assessed for each technique. The HPLC method for each Drug was evaluated in terms of assay variability and accuracy. The accuracy of the combined method ranged from 0.96 to 1.00 for artesunate tablets, chloroquine injectables, quinine capsules, and sulfadoxine tablets while the accuracy was 0.78 for enterically coated chloroquine tablets. These techniques provide a generally accurate, yet simple and affordable means to assess Drug Quality in resource-poor settings.
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counterfeit anti infective Drugs
Lancet Infectious Diseases, 2006Co-Authors: Michael Green, Paul N. Newton, Facundo M FernandezAbstract:Summary The production of counterfeit or substandard anti-infective Drugs is a widespread and under-recognised problem that contributes to morbidity, mortality, and Drug resistance, and leads to spurious reporting of resistance and toxicity and loss of confidence in health-care systems. Counterfeit Drugs particularly affect the most disadvantaged people in poor countries. Although advances in forensic chemical analysis and simple field tests will enhance Drug Quality monitoring, improved access to inexpensive genuine medicines, support of Drug regulatory authorities, more open reporting, vigorous law enforcement, and more international cooperation with determined political leadership will be essential to counter this threat.
Angus Bancroft - One of the best experts on this subject based on the ideXlab platform.
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concepts of illicit Drug Quality among darknet market users purity embodied experience craft and chemical knowledge
International Journal of Drug Policy, 2016Co-Authors: Angus Bancroft, Peter Scott ReidAbstract:Abstract Background Users of darknet markets refer to product Quality as one of the motivations for buying Drugs there, and vendors present Quality as a selling point. However, what users understand by Quality and how they evaluate it is not clear. This article investigates how users established and compared Drug Quality. Methods We used a two-stage method for investigating users’ assessments. The user forum of a darknet market that we called ‘Merkat’ was analysed to develop emergent themes. Qualitative interviews with darknet users were conducted, then forum data was analysed again. To enhance the applicability of the findings, the forum was sampled for users who presented as dependent as well as recreational. Results Quality could mean reliability, purity, potency, and predictability of effect. We focused on the different kinds of knowledge users drew on to assess Quality. These were: embodied; craft; and chemical. Conclusion Users’ evaluations of Quality depended on their experience, the purpose of use, and its context. Market forums are a case of indigenous harm reduction where users share advise and experiences and can be usefully engaged with on these terms.
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concepts of illicit Drug Quality among darknet market users purity embodied experience craft and chemical knowledge
Social Science Research Network, 2015Co-Authors: Angus Bancroft, Peter Scott ReidAbstract:Background: Users of darknet markets refer to product Quality as one of the motivations for buying Drugs there, and vendors present Quality as a selling point. However what users understand by Quality and how they evaluate it is not clear. This paper investigates how users established and compared Drug Quality. Methods: We used a two-stage method for investigating users' assessments. The user forum of a darknet market that we called 'Merkat' was analysed to develop emergent themes. Qualitative interviews with darknet users were conducted, then forum data was analysed again. To enhance the applicability of the findings, the forum was sampled for users who presented as dependent as well as recreational.Results: Quality could mean reliability, purity, potency, and predictability of effect. We focused on the different kinds of knowledge users drew on to assess Quality. These were: embodied; craft; and chemical. Conclusion: Users’ evaluations of Quality depended on their experience, the purpose of use, and its context. Market forums are a case of indigenous harm reduction where users share advise and experiences and can be usefully engaged with on these terms.Highlights:• We investigate how darknet market users assess Drug Quality• Market forums allow users to apply embodied, craft and chemical knowledge to compare the Quality of different products• Good Quality does not necessarily equate to high chemical purity• Different Drugs are assessed with different priorities in mindExpanding the range of knowledge types that users apply to product Quality may have positive implications for harm reduction.
Roger Bate - One of the best experts on this subject based on the ideXlab platform.
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anti malarial Drug Quality in lagos and accra a comparison of various Quality assessments
Malaria Journal, 2010Co-Authors: Roger Bate, Kimberly HessAbstract:Two major cities in West Africa, Accra, the capital of Ghana, and Lagos, the largest city of Nigeria, have significant problems with substandard pharmaceuticals. Both have actively combated the problem in recent years, particularly by screening products on the market using the Global Pharma Health Fund e.V. Minilab® protocol. Random sampling of medicines from the two cities at least twice over the past 30 months allows a tentative assessment of whether improvements in Drug Quality have occurred. Since intelligence provided by investigators indicates that some counterfeit producers may be adapting products to pass Minilab tests, the results are compared with those from a Raman spectrometer and discrepancies are discussed. Between mid-2007 and early-2010, samples of anti-malarial Drugs were bought covertly from pharmacies in Lagos on three different occasions (October 2007, December 2008, February 2010), and from pharmacies in Accra on two different occasions (October 2007, February 2010). All samples were tested using the Minilab® protocol, which includes disintegration and active ingredient assays as well as visual inspection, and most samples were also tested by Raman spectrometry. In Lagos, the failure rate in the 2010 sampling fell to 29% of the 2007 finding using the Minilab® protocol, 53% using Raman spectrometry, and 46% using visual inspection. In Accra, the failure rate in the 2010 sampling fell to 54% of the 2007 finding using the Minilab® protocol, 72% using Raman spectrometry, and 90% using visual inspection. The evidence presented shows that Drug Quality is probably improving in both cities, especially Lagos, since major reductions of failure rates over time occur with all means of assessment. Many more samples failed when examined by Raman spectrometry than by Minilab® protocol. The discrepancy is most likely caused by the two techniques measuring different aspects of the medication and hence the discrepancy may be the natural variation in these techniques. But other explanations are possible and are discussed.
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anti malarial Drug Quality in lagos and accra a comparison of various Quality assessments
2010Co-Authors: Roger Bate, Kimberly HessAbstract:Background: Two major cities in West Africa, Accra, the capital of Ghana, and Lagos, the largest city of Nigeria, have significant problems with substandard pharmaceuticals. Both have actively combated the problem in recent years, particularly by screening products on the market using the Global Pharma Health Fund e.V. Minilab® protocol. Random sampling of medicines from the two cities at least twice over the past 30 months allows a tentative assessment of whether improvements in Drug Quality have occurred. Since intelligence provided by investigators indicates that some counterfeit producers may be adapting products to pass Minilab tests, the results are compared with those from a Raman spectrometer and discrepancies are discussed. Methods: Between mid-2007 and early-2010, samples of anti-malarial Drugs were bought covertly from pharmacies in Lagos on three different occasions (October 2007, December 2008, February 2010), and from pharmacies in Accra on two different occasions (October 2007, February 2010). All samples were tested using the Minilab® protocol, which includes disintegration and active ingredient assays as well as visual inspection, and most samples were also tested by Raman spectrometry. Results: In Lagos, the failure rate in the 2010 sampling fell to 29% of the 2007 finding using the Minilab® protocol, 53% using Raman spectrometry, and 46% using visual inspection. In Accra, the failure rate in the 2010 sampling fell to 54% of the 2007 finding using the Minilab® protocol, 72% using Raman spectrometry, and 90% using visual inspection. Conclusions: The evidence presented shows that Drug Quality is probably improving in both cities, especially Lagos, since major reductions of failure rates over time occur with all means of assessment. Many more samples failed when examined by Raman spectrometry than by Minilab® protocol. The discrepancy is most likely caused by the two techniques measuring different aspects of the medication and hence the discrepancy may be the natural variation in these techniques. But other explanations are possible and are discussed.
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pilot study of essential Drug Quality in two major cities in india
PLOS ONE, 2009Co-Authors: Roger Bate, Richard Tren, Lorraine Mooney, Kimberly Hess, Barun Mitra, Bibek Debroy, Amir AttaranAbstract:Background: India is an increasingly influential player in the global pharmaceutical market. Key parts of the Drug regulatory system are controlled by the states, each of which applies its own standards for enforcement, not always consistent with others. A pilot study was conducted in two major cities in India, Delhi and Chennai, to explore the question/hypothesis/extent of substandard and counterfeit Drugs available in the market and to discuss how the Indian state and federal governments could improve Drug regulation and more importantly regulatory enforcement to combat these Drugs.Methodology/Principal Findings: Random samples of antimalarial, antibiotic, and antimycobacterial Drugs were collected from pharmacies in urban and peri-urban areas of Delhi and Chennai, India. Semi-quantitative thin-layer chromatography and disintegration testing were used to measure the concentration of active ingredients against internationally acceptable standards. 12% of all samples tested from Delhi failed either one or both tests, and were substandard. 5% of all samples tested from Chennai failed either one or both tests, and were substandard. Spatial heterogeneity between pharmacies was observed, with some having more or less substandard Drugs (30% and 0% respectively), as was product heterogeneity, with some Drugs being more or less frequently substandard (12% and 7% respectively).Conclusions/Significance: In a study using basic field-deployable techniques of lesser sensitivity rather than the most advanced laboratory-based techniques, the prevalence of substandard Drugs in Delhi and Chennai is confirmed to be roughly in accordance with the Indian government's current estimates. However, important spatial and product heterogeneity exists, which suggests that India's substandard Drug problem is not ubiquitous, but driven by a subset of manufacturers and pharmacies which thrive in an inadequately regulated environment. It is likely that the Drug regulatory system in India needs to be improved for domestic consumption, and because India is an increasingly important exporter of Drugs for both developed and developing countries. Some poor countries with high burdens of disease have weak Drug regulatory systems and import many HIV/AIDS, tuberculosis and malaria Drugs from India.
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antimalarial Drug Quality in the most severely malarious parts of africa a six country study
PLOS ONE, 2008Co-Authors: Roger Bate, Richard Tren, Philip Coticelli, Amir AttaranAbstract:A range of antimalarial Drugs were procured from private pharmacies in urban and peri-urban areas in the major cities of six African countries, situated in the part of that continent and the world that is most highly endemic for malaria. Semi-quantitative thin-layer chromatography (TLC) and dissolution testing were used to measure active pharmaceutical ingredient content against internationally acceptable standards. 35% of all samples tested failed either or both tests, and were substandard. Further, 33% of treatments collected were artemisinin monotherapies, most of which (78%) were manufactured in disobservance of an appeal by the World Health Organisation (WHO) to withdraw these clinically inappropriate medicines from the market. The high persistence of substandard Drugs and clinically inappropriate artemisinin monotherapies in the private sector risks patient safety and, through Drug resistance, places the future of malaria treatment at risk globally.
Facundo M Fernandez - One of the best experts on this subject based on the ideXlab platform.
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counterfeit and substandard anti infectives in developing countries
2010Co-Authors: Facundo M Fernandez, Michael D. Green, Paul N. Newton, Joyce Primocarpenter, Nicholas J WhiteAbstract:There is considerable interest in optimizing the therapy for important infections in developing countries and in making the best treatments readily available and inexpensive. There is also great concern that resistance to anti-infective Drugs is worsening, putting affordable treatments at risk. We argue that an important, but usually neglected aspect of these problems is Drug Quality. Drugs may be of poor Quality if they are counterfeit, substandard or degraded. Few objective data on the prevalence of poor-Quality Drugs exist but surveys suggest that an alarming proportion of antimalarials and antibiotics in much of the developing world are of poor Quality. For individual patients these will increase mortality and morbidity and lead to loss of faith in medicines and health systems. Counterfeit, substandard or degraded Drugs with sub-therapeutic concentrations of the active ingredient or the wrong active ingredient are likely to engender the emergence and spread of resistance to these anti-infectives. Although modelling suggests that poor-Quality Drug should worsen Drug resistance, there is sparse evidence from the field, as there has been little research. It will be very difficult to distinguish the effects of poor-Drug Quality and reduced patient adherence and incorrect health worker prescribing on the spread of resistance. Strengthening Drug regulatory authorities, improving Quality of Drug production and facilitating the availability of relatively inexpensive, good-Quality anti-infectives are likely to be key factors in improving Drug Quality.
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assessment of hand held raman instrumentation for in situ screening for potentially counterfeit artesunate antimalarial tablets by ft raman spectroscopy and direct ionization mass spectrometry
Analytica Chimica Acta, 2008Co-Authors: Camilla Ricci, Facundo M Fernandez, Paul N. Newton, Leonard Nyadong, Felicia Yang, Christopher D Brown, Sergei G KazarianAbstract:Pharmaceutical counterfeiting has become a significant public health problem worldwide and new, rapid, user-friendly, reliable and inexpensive methods for Drug Quality screening are needed. This work illustrates the chemical characterization of genuine and fake artesunate antimalarial tablets by portable Raman spectroscopy and validation by FT-Raman spectroscopy and ambient mass spectrometry. The applicability of a compact and robust portable Raman spectrometer (TruScan™) for the in situ chemical identification of counterfeit tablets is reported.
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Use of refractometry and colorimetry as field methods to rapidly assess antimalarial Drug Quality
Journal of Pharmaceutical and Biomedical Analysis, 2007Co-Authors: Michael D. Green, Henry Nettey, Ofelia Villalva Rojas, Chansapha Pamanivong, Lamphet Khounsaknalath, Miguel Grande Ortiz, Latsamy Vongsack, Facundo M Fernandez, Paul N. Newton, Ot ManolinAbstract:The proliferation of counterfeit and poor-Quality Drugs is a major public health problem; especially in developing countries lacking adequate resources to effectively monitor their prevalence. Simple and affordable field methods provide a practical means of rapidly monitoring Drug Quality in circumstances where more advanced techniques are not available. Therefore, we have evaluated refractometry, colorimetry and a technique combining both processes as simple and accurate field assays to rapidly test the Quality of the commonly available antimalarial Drugs; artesunate, chloroquine, quinine, and sulfadoxine. Method bias, sensitivity, specificity and accuracy relative to high-performance liquid chromatographic (HPLC) analysis of Drugs collected in the Lao PDR were assessed for each technique. The HPLC method for each Drug was evaluated in terms of assay variability and accuracy. The accuracy of the combined method ranged from 0.96 to 1.00 for artesunate tablets, chloroquine injectables, quinine capsules, and sulfadoxine tablets while the accuracy was 0.78 for enterically coated chloroquine tablets. These techniques provide a generally accurate, yet simple and affordable means to assess Drug Quality in resource-poor settings.
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counterfeit anti infective Drugs
Lancet Infectious Diseases, 2006Co-Authors: Michael Green, Paul N. Newton, Facundo M FernandezAbstract:Summary The production of counterfeit or substandard anti-infective Drugs is a widespread and under-recognised problem that contributes to morbidity, mortality, and Drug resistance, and leads to spurious reporting of resistance and toxicity and loss of confidence in health-care systems. Counterfeit Drugs particularly affect the most disadvantaged people in poor countries. Although advances in forensic chemical analysis and simple field tests will enhance Drug Quality monitoring, improved access to inexpensive genuine medicines, support of Drug regulatory authorities, more open reporting, vigorous law enforcement, and more international cooperation with determined political leadership will be essential to counter this threat.
