Additive manufacturing (3D printing) permits the fabrication of tablets in shapes unattainable by... more Additive manufacturing (3D printing) permits the fabrication of tablets in shapes unattainable by powder compaction, and so the effects of geometry on drug release behavior is easily assessed. Here, tablets (printlets) comprising of paracetamol dispersed in polyethylene glycol were printed using stereolithographic 3D printing. A number of geometric shapes were produced (cube, disc, pyramid, sphere and torus) with either constant surface area (SA) or constant surface area/volume ratio (SA/V). Dissolution testing showed that printlets with constant SA/V ratio released drug at the same rate, while those with constant SA released drug at different rates. A series of tori with increasing SA/V ratio (from 0.5 to 2.4) were printed, and it was found that dissolution rate increased as the SA/V ratio increased. The data show that printlets can be fabricated in multiple shapes and that dissolution performance can be maintained if the SA/V ratio is constant or that dissolution performance of pr...
Journal of the College of Physicians and Surgeons--Pakistan : JCPSP, 2015
To determine the acceptance of retinal screening, Laser uptake and subsequent follow-up in diabet... more To determine the acceptance of retinal screening, Laser uptake and subsequent follow-up in diabetic patients attending the Diabetes Centre of Diabetic Association of Pakistan (DAP), Karachi. Observational case series. Diabetic Centre of Diabetic Association of Pakistan (DAP), Karachi, from January 2011 to December 2012. All the diabetic patients were screened for Diabetic Retinopathy (DR) with non-Mydriatic Fundus Camera (NMFC). Patients with DR were examined by the ophthalmologist using fundus lens and slit lamp. DR was graded for severity on the basis of modified Airlie House Classification. Patients with Sight Threatening Diabetic Retinopathy (STDR) were advised Laser treatment. Each patient was followed-up for at least 6 months. The records of patients recommended Laser were retrieved, and called for re-examination. Retinal screening was accepted by all of the 8368 registered diabetics attending DAP Centre. On fundus photography, 21.2% (1777) individuals were found to have DR. S...
A 47-year-old female presented with a 1-year history of 'eczematous change' to the right ... more A 47-year-old female presented with a 1-year history of 'eczematous change' to the right nipple. Bilateral mammography and ultrasound were entirely normal. Free hand biopsy demonstrated invasive adenocarcinoma of the nipple. The patient underwent a right-sided central segmentectomy and sentinel node biopsy. Histology demonstrated that the nipple was almost completely replaced by an invasive ductal carcinoma with a maximum diameter of 13 mm. Invasion of the underlying breast tissue was to a depth of 3 mm. A single sentinel lymph node demonstrated metastatic carcinoma. Her oestrogen receptor status was positive while HER-2 status was negative. The patient subsequently underwent right-sided axillary node clearance to level three nodes. All 17 nodes in the specimen were found to be within normal limits. She is scheduled to undergo radiotherapy, chemotherapy and hormonal treatment. Copyright 2011 BMJ Publishing Group. All rights reserved.
ABSTRACT The evolution of conventional electric grid into Smart Grid (SG) has enabled utilities a... more ABSTRACT The evolution of conventional electric grid into Smart Grid (SG) has enabled utilities as well as consumers to reap fruits due to its time varying price mechanisms. The utilities can acquire benefits by improving stability of grid, lessening blackouts and brownouts, knowing better their consumers power needs and not investing into new infrastructures. On the other hand consumer can also reduce electric bills, gain incentives by installing renewable energy sources and exporting energy to the main grid and attain improved services from utility. Demand Response (DR) is one of the most cost effective and reliable techniques used by utilities for consumers load shifting. In this paper, we are presenting a review of several DR techniques with a specific view on pricing signals, optimization, appliance scheduling used and their benefits. A comprehensive performance comparison is also prepared with the help of multiple criteria of SG paradigm.
Large animals such as pigs are often used in drug delivery research prior to experiments in man. ... more Large animals such as pigs are often used in drug delivery research prior to experiments in man. However limited information is available on the rheological behavior of the fluids along the gastrointestinal (GI) tract of the pig. In this study we have measured the viscosities of pig GI fluid from the stomach to the colon to facilitate the development of simulated GI fluids that are rheologically relevant.
IEEE Antennas and Wireless Propagation Letters, 2015
ABSTRACT Phased MIMO (multiple input and multiple output) radar has been proposed in the recent y... more ABSTRACT Phased MIMO (multiple input and multiple output) radar has been proposed in the recent years to exploit the coherent processing gain of phased array radar and the waveform diversity of the MIMO radar. The transmit array is divided into subarrays of equal length to show some improvements as compared to both phased array and MIMO radar alone. In this letter, a hybrid phased MIMO radar with unequal subarrays has been proposed to steer multiple beams of different gain and unique waveforms towards a particular target. The unequal size and greater length of subarrays give an extra degree of freedom by illuminating the small targets with more focused beams. As a result, the echoes received by the receiver provide better information about the target. The effectiveness of proposed scheme is shown through simulation results.
Proceedings of the 2010 annual symposium on Computational geometry - SoCG '10, 2010
... Abdul Basit Dept ... of Computer Science LUMS, Pakistan abdulbasit@lums.edu.pk ... In particu... more ... Abdul Basit Dept ... of Computer Science LUMS, Pakistan abdulbasit@lums.edu.pk ... In particu-lar, they showed that in Rd, the centerpoint cannot give a better bound than the one above (set Ï„ = 1/(d + 1)). Their main result is an elegant construction of a point set P so that no point in ...
International journal of pharmaceutics, Jan 23, 2015
The aminosalicylate mesalazine (mesalamine) forms the mainstay of treatment in ulcerative colitis... more The aminosalicylate mesalazine (mesalamine) forms the mainstay of treatment in ulcerative colitis (UC); a disease for which many commercial modified-release products have been developed with the aim of providing targeted gastrointestinal release. The release profiles of five of these commercial formulations were evaluated in bicarbonate buffer using a novel dissolution model that mimics the dynamic conditions of the gastrointestinal tract. Monolithic and multi-particulate mesalazine formulations with pH-dependent and/or independent release mechanisms were evaluated (Asacol(®) 800, Octasa(®), Mezavant(®) XL, Salofalk(®), Pentasa(®)), and each of the products displayed a distinctive dissolution profile. The dissolution results for Mezavant(®) XL (Lialda(®)) (lag time 290min) demonstrated good correlation with previously reported in vivo disintegration times assessed by gamma-scintigraphy in humans. Octasa(®) showed a similar lag time to Mezavant(®) XL. Drug release from Asacol(®) 800 ...
Methamphetamine is a highly addictive psychostimulant that causes profound damage to the brain an... more Methamphetamine is a highly addictive psychostimulant that causes profound damage to the brain and other body organs. Post mortem studies of human tissues have linked the use of this drug to diseases associated with aging, such as coronary atherosclerosis and pulmonary fibrosis, but the molecular mechanism underlying these findings remains unknown. Here we used functional lipidomics and transcriptomics experiments to study abnormalities in lipid metabolism in select regions of the brain and, to a greater extent, peripheral organs and tissues of rats that self-administered methamphetamine. Experiments in various cellular models (primary mouse fibroblasts and myotubes) allowed us to investigate the molecular mechanisms of systemic inflammation and cellular aging related to methamphetamine abuse. We report now that methamphetamine accelerates cellular senescence and activates transcription of genes involved in cell-cycle control and inflammation by stimulating production of the sphingo...
Gastrointestinal physiology is dynamic and complex at the best of times, and a multitude of known... more Gastrointestinal physiology is dynamic and complex at the best of times, and a multitude of known variables can affect the overall bioavailability of drugs delivered via the oral route. Yet while the influences of food and beverage intake as just two of these variables on oral drug delivery have been extensively documented in the wider literature, specific information on their effects remains sporadic, and is not so much contextually reviewed. Food co-ingestion with oral dosage forms can mediate several changes to drug bioavailability, yet the precise mechanisms underlying this have yet to be fully elucidated. Likewise, the often detrimental effects of alcohol (ethanol) on dosage form performance have been widely observed experimentally, but knowledge of which has only moderately impacted on clinical practice. Here, we attempt to piece together the available subject matter relating to the influences of both solid and liquid foodstuffs on the gastrointestinal milieu and the implications for oral drug delivery, with particular emphasis on the behaviour of modified-release dosage forms, formulation robustness and drug absorption. Providing better insight into these influences, and exemplifying cases where formulations have been developed or modified to circumvent their associated problems, can help to appropriately direct the design of future in vitro digestive modelling systems as well as oral dosage forms resilient to these effects. Moreover, this will help to better our understanding of the impact of food and alcohol intake on normal gut behaviour and function.
Additive manufacturing (3D printing) permits the fabrication of tablets in shapes unattainable by... more Additive manufacturing (3D printing) permits the fabrication of tablets in shapes unattainable by powder compaction, and so the effects of geometry on drug release behavior is easily assessed. Here, tablets (printlets) comprising of paracetamol dispersed in polyethylene glycol were printed using stereolithographic 3D printing. A number of geometric shapes were produced (cube, disc, pyramid, sphere and torus) with either constant surface area (SA) or constant surface area/volume ratio (SA/V). Dissolution testing showed that printlets with constant SA/V ratio released drug at the same rate, while those with constant SA released drug at different rates. A series of tori with increasing SA/V ratio (from 0.5 to 2.4) were printed, and it was found that dissolution rate increased as the SA/V ratio increased. The data show that printlets can be fabricated in multiple shapes and that dissolution performance can be maintained if the SA/V ratio is constant or that dissolution performance of pr...
Journal of the College of Physicians and Surgeons--Pakistan : JCPSP, 2015
To determine the acceptance of retinal screening, Laser uptake and subsequent follow-up in diabet... more To determine the acceptance of retinal screening, Laser uptake and subsequent follow-up in diabetic patients attending the Diabetes Centre of Diabetic Association of Pakistan (DAP), Karachi. Observational case series. Diabetic Centre of Diabetic Association of Pakistan (DAP), Karachi, from January 2011 to December 2012. All the diabetic patients were screened for Diabetic Retinopathy (DR) with non-Mydriatic Fundus Camera (NMFC). Patients with DR were examined by the ophthalmologist using fundus lens and slit lamp. DR was graded for severity on the basis of modified Airlie House Classification. Patients with Sight Threatening Diabetic Retinopathy (STDR) were advised Laser treatment. Each patient was followed-up for at least 6 months. The records of patients recommended Laser were retrieved, and called for re-examination. Retinal screening was accepted by all of the 8368 registered diabetics attending DAP Centre. On fundus photography, 21.2% (1777) individuals were found to have DR. S...
A 47-year-old female presented with a 1-year history of 'eczematous change' to the right ... more A 47-year-old female presented with a 1-year history of 'eczematous change' to the right nipple. Bilateral mammography and ultrasound were entirely normal. Free hand biopsy demonstrated invasive adenocarcinoma of the nipple. The patient underwent a right-sided central segmentectomy and sentinel node biopsy. Histology demonstrated that the nipple was almost completely replaced by an invasive ductal carcinoma with a maximum diameter of 13 mm. Invasion of the underlying breast tissue was to a depth of 3 mm. A single sentinel lymph node demonstrated metastatic carcinoma. Her oestrogen receptor status was positive while HER-2 status was negative. The patient subsequently underwent right-sided axillary node clearance to level three nodes. All 17 nodes in the specimen were found to be within normal limits. She is scheduled to undergo radiotherapy, chemotherapy and hormonal treatment. Copyright 2011 BMJ Publishing Group. All rights reserved.
ABSTRACT The evolution of conventional electric grid into Smart Grid (SG) has enabled utilities a... more ABSTRACT The evolution of conventional electric grid into Smart Grid (SG) has enabled utilities as well as consumers to reap fruits due to its time varying price mechanisms. The utilities can acquire benefits by improving stability of grid, lessening blackouts and brownouts, knowing better their consumers power needs and not investing into new infrastructures. On the other hand consumer can also reduce electric bills, gain incentives by installing renewable energy sources and exporting energy to the main grid and attain improved services from utility. Demand Response (DR) is one of the most cost effective and reliable techniques used by utilities for consumers load shifting. In this paper, we are presenting a review of several DR techniques with a specific view on pricing signals, optimization, appliance scheduling used and their benefits. A comprehensive performance comparison is also prepared with the help of multiple criteria of SG paradigm.
Large animals such as pigs are often used in drug delivery research prior to experiments in man. ... more Large animals such as pigs are often used in drug delivery research prior to experiments in man. However limited information is available on the rheological behavior of the fluids along the gastrointestinal (GI) tract of the pig. In this study we have measured the viscosities of pig GI fluid from the stomach to the colon to facilitate the development of simulated GI fluids that are rheologically relevant.
IEEE Antennas and Wireless Propagation Letters, 2015
ABSTRACT Phased MIMO (multiple input and multiple output) radar has been proposed in the recent y... more ABSTRACT Phased MIMO (multiple input and multiple output) radar has been proposed in the recent years to exploit the coherent processing gain of phased array radar and the waveform diversity of the MIMO radar. The transmit array is divided into subarrays of equal length to show some improvements as compared to both phased array and MIMO radar alone. In this letter, a hybrid phased MIMO radar with unequal subarrays has been proposed to steer multiple beams of different gain and unique waveforms towards a particular target. The unequal size and greater length of subarrays give an extra degree of freedom by illuminating the small targets with more focused beams. As a result, the echoes received by the receiver provide better information about the target. The effectiveness of proposed scheme is shown through simulation results.
Proceedings of the 2010 annual symposium on Computational geometry - SoCG '10, 2010
... Abdul Basit Dept ... of Computer Science LUMS, Pakistan abdulbasit@lums.edu.pk ... In particu... more ... Abdul Basit Dept ... of Computer Science LUMS, Pakistan abdulbasit@lums.edu.pk ... In particu-lar, they showed that in Rd, the centerpoint cannot give a better bound than the one above (set Ï„ = 1/(d + 1)). Their main result is an elegant construction of a point set P so that no point in ...
International journal of pharmaceutics, Jan 23, 2015
The aminosalicylate mesalazine (mesalamine) forms the mainstay of treatment in ulcerative colitis... more The aminosalicylate mesalazine (mesalamine) forms the mainstay of treatment in ulcerative colitis (UC); a disease for which many commercial modified-release products have been developed with the aim of providing targeted gastrointestinal release. The release profiles of five of these commercial formulations were evaluated in bicarbonate buffer using a novel dissolution model that mimics the dynamic conditions of the gastrointestinal tract. Monolithic and multi-particulate mesalazine formulations with pH-dependent and/or independent release mechanisms were evaluated (Asacol(®) 800, Octasa(®), Mezavant(®) XL, Salofalk(®), Pentasa(®)), and each of the products displayed a distinctive dissolution profile. The dissolution results for Mezavant(®) XL (Lialda(®)) (lag time 290min) demonstrated good correlation with previously reported in vivo disintegration times assessed by gamma-scintigraphy in humans. Octasa(®) showed a similar lag time to Mezavant(®) XL. Drug release from Asacol(®) 800 ...
Methamphetamine is a highly addictive psychostimulant that causes profound damage to the brain an... more Methamphetamine is a highly addictive psychostimulant that causes profound damage to the brain and other body organs. Post mortem studies of human tissues have linked the use of this drug to diseases associated with aging, such as coronary atherosclerosis and pulmonary fibrosis, but the molecular mechanism underlying these findings remains unknown. Here we used functional lipidomics and transcriptomics experiments to study abnormalities in lipid metabolism in select regions of the brain and, to a greater extent, peripheral organs and tissues of rats that self-administered methamphetamine. Experiments in various cellular models (primary mouse fibroblasts and myotubes) allowed us to investigate the molecular mechanisms of systemic inflammation and cellular aging related to methamphetamine abuse. We report now that methamphetamine accelerates cellular senescence and activates transcription of genes involved in cell-cycle control and inflammation by stimulating production of the sphingo...
Gastrointestinal physiology is dynamic and complex at the best of times, and a multitude of known... more Gastrointestinal physiology is dynamic and complex at the best of times, and a multitude of known variables can affect the overall bioavailability of drugs delivered via the oral route. Yet while the influences of food and beverage intake as just two of these variables on oral drug delivery have been extensively documented in the wider literature, specific information on their effects remains sporadic, and is not so much contextually reviewed. Food co-ingestion with oral dosage forms can mediate several changes to drug bioavailability, yet the precise mechanisms underlying this have yet to be fully elucidated. Likewise, the often detrimental effects of alcohol (ethanol) on dosage form performance have been widely observed experimentally, but knowledge of which has only moderately impacted on clinical practice. Here, we attempt to piece together the available subject matter relating to the influences of both solid and liquid foodstuffs on the gastrointestinal milieu and the implications for oral drug delivery, with particular emphasis on the behaviour of modified-release dosage forms, formulation robustness and drug absorption. Providing better insight into these influences, and exemplifying cases where formulations have been developed or modified to circumvent their associated problems, can help to appropriately direct the design of future in vitro digestive modelling systems as well as oral dosage forms resilient to these effects. Moreover, this will help to better our understanding of the impact of food and alcohol intake on normal gut behaviour and function.
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