What Do Libyan Doctors Perceive as the Benefits, Ethical Issues and Influences of Their Interactions With Pharmaceutical Company Representatives?

What do Libyan doctors perceive as the benefits, ethical issues and influences of their interactions with pharmaceutical company representatives?

Pan Afr Med J. 2013; 14: 132
Alssageer MA, Kowalski SR

Evidence suggests that 80-90% of doctors in most countries across the world are frequently visited by pharmaceutical company representatives (PCRs). The objective of study to examine perceptions of Libyan doctors between August and October 2010, regarding the benefits, ethical issues and influences of their interactions with (PCRs).An anonymous questionnaire was circulated to 1,000 Libyan doctors in selected public and private practice settings in Tripoli, Benghazi and Sebha.The major benefits of PCR visits reported in the 608 evaluable responses were; receiving new information about products (94.4%). The majority of doctors (75%) were not against the provision of gifts but were more comfortable if it was “cheap” (51%) and had educational value (51%). Doctors who received more printed materials, simple gifts or drug samples were less likely to disapprove of accepting gifts (p5]. Effective marketing can positively influence an individual’s attitude towards a product and because there is an association between attitude, intention and behaviour [6], persuasive communication can generate a positive attitude and increase the potential for influence [7]. PCRs can accomplish behaviour change because they directly communicate with prescribers. During a visit they attempt to raise awareness of their products, provide product information and encourage a favourable attitude towards their company and product [8]. They employ verbal persuasion techniques and also provide other incentives such as gifts, free drug samples and sponsored educational events [2]. The provision of promotional gifts can be seen as a friendship building technique to reinforce the communication nexus between PCRs and doctors but it can also potentially erode professional barriers [9]. Contact between a PCR and a medical practitioner is therefore viewed by drug companies as a vital part of their marketing strategy and frequent visits, together with written promotional materials, gifts and other incentives, can help alter behaviour even if the initial attitudes towards a product were weak or unclear [10]. HubMed – drug


Genetic mechanisms of antimicrobial resistance identified in Salmonella enterica, Escherichia coli, and Enteroccocus spp. isolated from U.S. food animals.

Front Microbiol. 2013; 4: 135
Frye JG, Jackson CR

The prevalence of antimicrobial resistance (AR) in bacteria isolated from U.S. food animals has increased over the last several decades as have concerns of AR foodborne zoonotic human infections. Resistance mechanisms identified in U.S. animal isolates of Salmonella enterica included resistance to aminoglycosides (e.g., alleles of aacC, aadA, aadB, ant, aphA, and StrAB), ?-lactams (e.g., bla CMY-2, TEM-1, PSE-1), chloramphenicol (e.g., floR, cmlA, cat1, cat2), folate pathway inhibitors (e.g., alleles of sul and dfr), and tetracycline [e.g., alleles of tet(A), (B), (C), (D), (G), and tetR]. In the U.S., multi-drug resistance (MDR) mechanisms in Salmonella animal isolates were associated with integrons, or mobile genetic elements (MGEs) such as IncA/C plasmids which can be transferred among bacteria. It is thought that AR Salmonella originates in food animals and is transmitted through food to humans. However, some AR Salmonella isolated from humans in the U.S. have different AR elements than those isolated from food animals, suggesting a different etiology for some AR human infections. The AR mechanisms identified in isolates from outside the U.S. are also predominantly different. For example the extended spectrum ?-lactamases (ESBLs) are found in human and animal isolates globally; however, in the U.S., ESBLs thus far have only been found in human and not food animal isolates. Commensal bacteria in animals including Escherichia coli and Enterococcus spp. may be reservoirs for AR mechanisms. Many of the AR genes and MGEs found in E. coli isolated from U.S. animals are similar to those found in Salmonella. Enterococcus spp. isolated from animals frequently carry MGEs with AR genes, including resistances to aminoglycosides (e.g., alleles of aac, ant, and aph), macrolides [e.g., erm(A), erm(B), and msrC], and tetracyclines [e.g., tet(K), (L), (M), (O), (S)]. Continuing investigations are required to help understand and mitigate the impact of AR bacteria on human and animal health. HubMed – drug


Suprachoroidal delivery in a rabbit ex vivo eye model: influence of drug properties, regional differences in delivery, and comparison with intravitreal and intracameral routes.

Mol Vis. 2013; 19: 1198-210
Kadam RS, Williams J, Tyagi P, Edelhauser HF, Kompella UB

First, to determine the influence of drug lipophilicity (using eight beta-blockers) and molecular weight (using 4 kDa and 40 kDa fluoroscein isothiocyanate [FITC]-dextrans) on suprachoroidal delivery to the posterior segment of the eye by using a rabbit ex vivo eye model. Second, to determine whether drug distribution differs between the dosed and undosed side of the eye following suprachoroidal delivery. Third, to compare the suprachoroidal delivery of sodium fluorescein (NaF) with the intracameral and intravitreal routes by using noninvasive fluorophotometry.Using a small hypodermic 26G needle (3/8″) with a short bevel (250 µm), location of the suprachoroidal injection in an ex vivo New Zealand white rabbit eye model was confirmed with India ink. Ocular tissue distribution of NaF (25 µl of 1.5 µg/ml) at 37 °C was monitored noninvasively using the Fluorotron Master(TM) at 0, 1, and 3 h following suprachoroidal, intravitreal, or intracameral injections in ex vivo rabbit eyes. For assessing the influence of lipophilicity and molecular size, 25 µl of a mixture of eight beta-blockers (250 µg/ml each) or FITC-dextran (4 kDa and 40 kDa, 30 mg/ml) was injected into the suprachoroidal space of excised rabbit eyes and incubated at 37 °C. Eyes were incubated for 1 and 3 h, and frozen at the end of incubation. Ocular tissues were isolated in frozen condition. Beta-blocker and FITC-dextran levels in excised ocular tissue were measured by liquid chromatography-tandem mass spectrometry and spectrofluorometry, respectively.Histological sections of India ink-injected albino rabbit eye showed the localization of dye as a black line in the suprachoroidal space. Suprachoroidal injection of NaF showed signal localization to the choroid and retina at 1 and 3 h post injection when compared with intravitreal and intracameral injections. Drug delivery to the vitreous after suprachoroidal injection decreased with an increase in solute lipophilicity and molecular weight. With an increase in drug lipophilicity, drug levels in the choroid-retinal pigment epithelium (RPE) and retina generally increased with some exceptions. Beta-blockers and FITC-dextrans were localized more to the dosed side when compared to the opposite side of the sclera, choroid-RPE, retina, and vitreous. These differences were greater for FITC-dextrans as compared to the beta-blockers.The suprachoroidal route of injection allows localized delivery to the choroid-RPE and retina for small as well as large molecules. Suprachoroidal drug delivery to the vitreous declines with an increase in drug lipophilicity and molecular weight. Drug delivery differs between the dosed and opposite sides following suprachoroidal injection, at least up to 3 h. HubMed – drug


Engineering a Blood-Retinal Barrier With Human Embryonic Stem Cell-Derived Retinal Pigment Epithelium: Transcriptome and Functional Analysis.

Stem Cells Transl Med. 2013 Jun 3;
Peng S, Gan G, Qiu C, Zhong M, An H, Adelman RA, Rizzolo LJ

Retinal degenerations are a major cause of impaired vision in the elderly. Degenerations originate in either photoreceptors or the retinal pigment epithelium (RPE). RPE forms the outer blood-retinal barrier and functions intimately with photoreceptors. Animal models and cultures of RPE are commonly used to screen potential pharmaceuticals or explore RPE replacement therapy, but human RPE differs from that of other species. Human RPE forms a barrier using tight junctions composed of a unique set of claudins, proteins that determine the permeability and selectivity of tight junctions. Human adult RPE fails to replicate these properties in vitro. To develop a culture model for drug development and tissue-engineering human retina, RPE were derived from human embryonic stem cells (hESCs). Barrier properties of RPE derived from the H1 and H9 hESC lines were compared with a well-regarded model of RPE function, human fetal RPE isolated from 16-week-gestation fetuses (hfRPE). A serum-free medium (SFM-1) that enhanced the redifferentiation of hfRPE in culture also furthered the maturation of hESC-derived RPE. In SFM-1, the composition, selectivity, and permeability of tight junctions were similar to those of hfRPE. Comparison of the transcriptomes by RNA sequencing and quantitative reverse transcription-polymerase chain reaction revealed a high correlation between the hESCs and hfRPE, but there were notable differences in the expression of adhesion junction and membrane transport genes. These data indicated that hESC-derived RPE is highly differentiated but may be less mature than RPE isolated from 16-week fetuses. The study identified a panel of genes to monitor the maturation of RPE. HubMed – drug