Quantifying the use of the statin antilipemic drugs: Comparisons and contrasts between Nova Scotia, Canada, and Queensland, Australia

Background: jurisdictions are developing public drug insurance systems to improve access to pharmaceuticals, cost-effective prescribing, and patient health and well-being. We compared 2 Jurisdictions with different pharmaceutical policies to determine prescribing patterns for 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (le, statins). Objective: The aim of this work was to investigate the feasibility of using available prescription admimstrative databases to compare the use of statins in Queensland, Australia, and in Nova Scotia, Canada. Methods: Data from the Nova Scotia Pharmacare Program and the Health Insurance Commission in Australia were used to obtain dispensing data. Utilization was compared for the 5-year period from 1997 through 2001, using the World Health Organization anatomic therapeutic chemical/defined daily dose (DDD) system. Results: In the year 2001, there were 177,000 beneficiaries in the public drug plan in Nova Scotia (62% aged ≥ 65 years old) and 960,000 concession beneficiaries (pensioners and social security recipients, 61% aged ≥ 65 years) in Queensland. These 2 groups were comparable. The overall utilization of statin medications increased steadily in both areas over the study period, from 50 to 205 DDD/1000 beneficiaries per day. Comparison of the 2 growth lines showed no statistically significant differences in overall statin use despite differences in brand availabilities and policies about prescribing. In the year 2001, atorvastatin was the most commonly prescribed statin in both areas, comprising 46% of statin use in Nova Scotia and 51% in Queensland. Mean doses of each statin prescribed were slightly above the DDDs. Expenditure on statins per 1000 beneficiaries and per DDD were similar in each jurisdiction, being slightly higher in Nova Scotia. Conclusions: Despite differences in pharmaceutical reimbursement systems, use of the statins was similar in Nova Scotia and Queensland. The feasibility of the methodology was demonstrated. Future studies, including comparisons of drug utilization for other classes of drugs for which drug policies may be divergent (eg, different pricing structures or prior authorization requirements), or for which less evidence for appropriate use is available, may be useful. © 2005 Excerpta Medica, Inc.

On the optimal ratio of heavy to light chain genes for efficient recombinant antibody production by CHO cells

Monoclonal antibodies (Mab) are heterotetramers consisting of an equimolar ratio of heavy chain (HC) and light chain (LC) polypeptides. Accordingly, most recombinant Mab expression systems utilize an equimolar ratio of heavy chain (he) to light chain (lc) genes encoded on either one or two plasmids. However, there is no evidence to suggest that this gene ratio is optimal for stable or transient production of recombinant Mab. In this study we have determined the optimal ratio of hc:lc genes for production of a recombinant IgG(4) Mab, cB72.3, by Chinese hamster ovary (CHO) cells using both empirical and mathematical modeling approaches. Polyethyleneimine-mediated transient expression of cB72.3 at varying ratios of hc:lc genes encoded on separate plasmids yielded an optimal Mab titer at a hc:lc gene ratio of 3:2; a conclusion confirmed by separate mathematical modeling of the Mab folding and assembly process using transient expression data. On the basis of this information, we hypothesized that utilization of he genes at low hc:lc gene ratios is more efficient. To confirm this, cB72.3 Mab was transiently produced by CHO cells at constant he and varying lc gene dose. Under these conditions, Mab yield was increased with a concomitant increase in lc gene dose. To determine if the above findings also apply to stably transfected CHO cells producing recombinant Mab, we compared the intra- and extracellular ratios of HC and LC polypeptides for three GS-CHO cells lines transfected with a 1:1 ratio of hc:lc genes and selected for stable expression of the same recombinant Mab, cB72.3. Intra- and extracellular HC:LC polypeptide ratios ranged from 1:2 to 1:5, less than that observed on transient expression of the same Mab in parental CHO cells using the same vector. In conclusion, our data suggest that the optimal ratio of hc:lc genes used for transient and stable expression of Mab differ. In the case of the latter, we infer that optimal Mab production by stably transfected cells represents a compromise between HC abundance limiting productivity and the requirement for excess LC to render Mab folding and assembly more efficient.

Synthesis of gadolinium-labeled shell-crosslinked nanoparticles for magnetic resonance imaging applications

Shell-crosslinked knedel-like nanoparticles (SCKs; knedel is a Polish term for dumplings) were derivatized with gadolinium Shell chelates and studied as robust magnetic-resonance-imaging-active structures with hydrodynamic diameters of 40 +/- 3 nm. SCKs possessing an amphiphilic core-shell morphology were produced from the aqueous assembly of diblock copolymers of poly(acrylic acid) (PAA) and poly(methyl acrylate) (PMA), PAA(52)-b-PMA(128), and subsequent covalent crosslinking by amidation upon reaction with 2,2'-(ethylenedioxy)bis(ethylamine) throughout the shell layer. The properties of these materials, including non-toxicity towards mammalian cells, non-immunogenicity within mice, and capability for polyvalent targeting, make them ideal candidates for utilization within biological systems. The synthesis of SCKs derivatized with Gd-III and designed for potential use as a unique nanometer-scale contrast agent for MRI applications is described herein. Utilization of an amino-functionalized diethylenetriaminepentaacetic acid-Gd analogue allowed for direct covalent conjugation throughout the hydrophilic shell layer of the SCKs and served to increase the rotational correlation lifetime of the Gd. In addition, the highly hydrated nature of the shell layer in which the Gd was located allowed for rapid water exchange; thus, the resulting material demonstrated large ionic relaxivities (39 s(-1) mM(-1)) in an applied magnetic field of 0.47 T at 40 degrees C and, as a result of the large loading capacity of the material, also demonstrated high molecular relaxivities (20 000 s(-1) mM(-1)).

Optimization of a transplant model to assess skin reconstitution from stem cell-enriched primary human keratinocyte populations

Given that an important functional attribute of stem cells in vivo is their ability to sustain tissue regeneration, we set out to establish a simple and easy technique to assess this property from candidate populations of human keratinocyte stem cells in an in vivo setting. Keratinocytes were inoculated into devitalized rat tracheas and transplanted subcutaneously into SCID mice, and the epithelial lining regenerated characterized to establish the validity of this heterotypic model. Furthermore, the rate and quality of epidermal tissue reconstitution obtained from freshly isolated unfractionated vs. keratinocyte stem cell-enriched populations was tested as a function of (a) cell numbers inoculated; and (b) the inclusion of irradiated support keratinocytes and dermal cells. Rapid and sustained epidermal tissue regeneration from small numbers of freshly isolated human keratinocyte stem cells validates the utilization of this simple and reliable model system to assay for enrichment of epidermal tissue-reconstituting cells.

Human SULT1A genes: Cloning and activity assays of the SULT1A promoters

The three human SULT1A sulfotransferase enzymes are closely related in amino acid sequence (>90%), yet differ in their substrate preference and tissue distribution. SULT1A1 has a broad tissue distribution and metabolizes a range of xenobiotics as well as endogenous substrates such as estrogens and iodothyronines. While the localization of SULT1A2 is poorly understood, it has been shown to metabolize a number of aromatic amines. SULT1A3 is the major catecholamine sulfonating form, which is consistent with it being expressed principally in the gastrointestinal tract. SULT1A proteins are encoded by three separate genes, located in close proximity to each other on chromosome 16. The presence of differential 5′-untranslated regions identified upon cloning of the SULT1A cDNAs suggested the utilization of differential transcriptional start sites and/or differential splicing. This chapter describes the methods utilized by our laboratory to clone and assay the activity of the promoters flanking these different untranslated regions found on SULT1A genes. These techniques will assist investigators in further elucidating the differential mechanisms that control regulation of the human SULT1A genes. They will also help reveal how different cellular environments and polymorphisms affect the activity of SULT1A gene promoters.

Introduction of routine outcome measures: staff reactions and issues for consideration

The aim of this study was to explore clinician reactions to (i) the introduction of routine outcome measures and (ii) the utility of outcomes data in clinical practice. Focus group discussions (n = 34) were conducted with mental health staff (n = 324) at approximately 8 months post implementation of routine outcome measures. A semi-structured interview schedule was used to collect data on two key issues; reactions to the introduction of outcome measures and factors influencing the utility of outcomes data in clinical practice. Data from the discussion groups were analysed using content analysis to isolate emerging themes. While the majority of participants endorsed the collection and utilization of outcomes data, many raised questions about the merits of the initiative. Ambivalence, competing work demands, lack of support from senior medical staff, questionable evidence to support the use of outcome measures, and fear of how outcomes data might be used emerged as key issues. At 8 months post implementation a significant number of clinical staff remained ambivalent about the benefits of outcome measurement and had not engaged in the process. The shift to a service model driven by outcomes and case-mix data will take time and resources to achieve. Implications for nursing staff are discussed.

Incremental cost-effectiveness of exercise echocardiography vs. SPECT imaging for the evaluation of stable chest pain

Aims Technological advances in cardiac imaging have led to dramatic increases in test utilization and consumption of a growing proportion of cardiovascular healthcare costs. The opportunity costs of strategies favouring exercise echocardiography or SPECT imaging have been incompletely evaluated. Methods and results We examined prognosis and cost-effectiveness of exercise echocardiography (n=4884) vs. SPECT (n=4637) imaging in stable, intermediate risk, chest pain patients. Ischaemia extent was defined as the number of vascular territories with echocardiographic wall motion or SPECT perfusion abnormalities. Cox proportional hazard models were employed to assess time to cardiac death or myocardial infarction (MI). Total cardiovascular costs were summed (discounted and inflation-corrected) throughout follow-up. A cost-effectiveness ratio = 2% annual event risk), SPECT ischaemia was associated with earlier and greater utilization of coronary revascularization (P < 0.0001) resulting in an incremental cost-effectiveness ratio of $32 381/LYS. Conclusion Health care policies aimed at allocating limited resources can be effectively guided by applying clinical and economic outcomes evidence. A strategy aimed at cost-effective testing would support using echocardiography in low-risk patients with suspected coronary disease, whereas those higher risk patients benefit from referral to SPECT imaging.

Production of Enzymatically active ketosteroid isomerase following insoluble expression in Escherichia coli

Enzymatically active Delta(5)-3-ketosteroid isomerase (KSI) protein with a C-terminus his(6)-tag was produced following insoluble expression using Escherichia coli. A simple, integrated process was used to extract and purify the target protein. Chemical extraction was shown to be as effective as homogenization at releasing the inclusion body proteins from the bacteria] cells, with complete release taking less than 20 min. An expanded bed adsorption (EBA) column utilizing immobilized metal affinity chromatography (IMAC) was then used to purify the denatured KSI-(His(6)) protein directly from the chemical extract. This integrated process greatly simplifies the recovery and purification of inclusion body proteins by removing the need for mechanical cell disruption, repeated inclusion body centrifugation, and difficult clarification operations. The integrated chemical extraction and EBA process achieved a very high purity (99%) and recovery (89%) of the KSI-(His(6)), with efficient utilization of the adsorbent matrix (9.74 mg KSI-(His(6))/mL adsorbent). Following purification the protein was refolded by dilution to obtain the biologically active protein. Seventy-nine percent of the expressed KSI-(His(6)) protein was recovered as enzymatically active protein with the described extraction, purification, and refolding process. In addition to demonstrating the operation of this intensified inclusion body process, a plate-based concentration assay detecting KSI-(His(6)) is validated. The intensified process in this work requires minimal optimization for recovering novel his-tagged proteins, and further improves the economic advantage of E. coli as a host organism. (c) 2006 Wiley Periodicals, Inc.

The management of interdependence and the sharing of vision by micro-finance agencies for new and emerging SMEs

The purpose of this paper is to conceptualise a theoretical model that clarifies the variations in both processes for sharing vision and interdependence of the lender and the SME owner in micro-finance. Processes for sharing vision and interdependence are possible predictors of the effective tacit and explicit knowledge generation/utilization of a micro-finance agency – SME owner relationship. For new and emerging SMEs the micro-finance agency can provide a critical role in their development. Micro-finance agencies can provide a mechanism in economic development that enables SMEs to have greater speed to markets. The focus of this paper is on the relationship between the micro-finance lending officer and the SME owner. Specifically, the model developed in this paper informs understanding the nature of knowledge generation/utilization between micro-finance agencies and SMEs. Effective generation/utilization facilitates the assessment of the risk for investment. The model clarifies the variations between interdependence and the development of processes for sharing of vision. When you have high interdependence (characterised by good cooperation) and effective processes for sharing of vision, an environment of effective knowledge generation/utilization is likely to be created between the micro-finance agency and the SME owner. The model proposes that the effective management of both tacit and explicit knowledge between the micro-finance agency and SMEs supports them to reach their markets. Implications of this research for SMEs and micro-finance agencies include the increase of knowledge and understanding of SME processes.

Novel monoclonal antibody recognition of oxidative DNA damage adduct, deoxycytidine-glyoxal

Glyoxal, a reactive aldehyde, is a decomposition product of lipid hydroperoxides, oxidative deoxyribose breakdown, or autoxidation of sugars, such as glucose. It readily forms DNA adducts, generating potential carcinogens such as glyoxalated deoxycytidine (gdC). A major drawback in assessing gdC formation in cellular DNA has been methodologic sensitivity. We have developed an mAb that specifically recognizes gdC. Balb/c mice were immunized with DNA, oxidatively modified by UVC/hydrogen peroxide in the presence of endogenous metal ions. Although UVC is not normally considered an oxidizing agent, a UVC/hydrogen peroxide combination may lead to glyoxalated bases arising from hydroxyl radical damage to deoxyribose. This damaging system was used to induce numerous oxidative lesions including glyoxal DNA modifications, from which resulted a number of clones. Clone F3/9/H2/G5 showed increased reactivity toward glyoxal-modified DNA greater than that of the immunizing antigen. ELISA unequivocally showed Ab recognition toward gdC, which was confirmed by gas chromatography-mass spectrometry of the derivatized adduct after formic acid hydrolysis to the modified base. Binding of Ab F3/9 with glyoxalated and untreated oligomers containing deoxycytidine, deoxyguanosine, thymidine, and deoxyadenosine assessed by ELISA produced significant recognition (p 0.0001) of glyoxal-modified deoxycytidine greater than that of untreated oligomer. Additionally, inhibition ELISA studies using the glyoxalated and native deoxycytidine oligomer showed increased recognition for gdC with more than a 5-fold difference in IC50 values. DNA modified with increasing levels of iron (II)/EDTA produced a dose-dependent increase in Ab F3/9 binding. This was reduced in the presence of catalase or aminoguanidine. We have validated the potential of gdC as a marker of oxidative DNA damage and showed negligible cross-reactivity with 8-oxo-2'-deoxyguanosine or malondialdehyde-modified DNA as well as its utility in immunocytochemistry. Formation of the gdC adduct may involve intermediate structures; however, our results strongly suggest Ab F3/9 has major specificity for the predominant product, 5-hydroxyacetyl-dC.

The authority of complexity

The assertion about the unique 'complexity' or the peculiarly intricate character of social phenomena has, at least within sociology, a long, venerable and virtually uncontested tradition. At the turn of the last century, classical social theorists, for example, Georg Simmel and Emile Durkheim, made prominent and repeated reference to this attribute of the subject matter of sociology and the degree to which it complicates, even inhibits the development and application of social scientific knowledge. Our paper explores the origins, the basis and the consequences of this assertion and asks in particular whether the classic complexity assertion still deserves to be invoked in analyses that ask about the production and the utilization of social scientific knowledge in modern society. We present John Maynard Keynes' economic theory and its practical applications as an illustration. We conclude that the practical value of social scientific knowledge is not dependent on a faithful, in the sense of complete, representation of social reality. Instead, social scientific knowledge that wants to optimize its practicality has to attend and attach itself to elements of social situations that can be altered or are actionable.

The unique complexity of social phenomena and the uses of social science knowledge

The assertion about the peculiarly intricate and complex character of social phenomena has, in much of social discourse, a virtually uncontested tradition. A significant part of the premise about the complexity of social phenomena is the conviction that it complicates, perhaps even inhibits the development and application of social scientific knowledge. Our paper explores the origins, the basis and the consequences of this assertion and asks in particular whether the classic complexity assertion still deserves to be invoked in analyses that ask about the production and the utilization of social scientific knowledge in modern society. We refer to one of the most prominent and politically influential social scientific theories, John Maynard Keynes' economic theory as an illustration. We conclude that, the practical value of social scientific knowledge is not necessarily dependent on a faithful, in the sense of complete, representation of (complex) social reality. Practical knowledge is context sensitive if not project bound. Social scientific knowledge that wants to optimize its practicality has to attend and attach itself to elements of practical social situations that can be altered or are actionable by relevant actors. This chapter represents an effort to re-examine the relation between social reality, social scientific knowledge and its practical application. There is a widely accepted view about the potential social utility of social scientific knowledge that invokes the peculiar complexity of social reality as an impediment to good theoretical comprehension and hence to its applicability.

Multiphase modelling of the characteristics of close coupled gas atomization

Not withstanding the high demand of metal powder for automotive and High Tech applications, there are still many unclear aspects of the production process. Only recentlyhas supercomputer performance made possible numerical investigation of such phenomena. This thesis focuses on the modelling aspects of primary and secondary atomization. Initially two-dimensional analysis is carried out to investigate the influence of flow parameters (reservoir pressure and gas temperature principally) and nozzle geometry on final powder yielding. Among the different types, close coupled atomizers have the best performance in terms of cost and narrow size distribution. An isentropic contoured nozzle is introduced to minimize the gas flow losses through shock cells: the results demonstrate that it outperformed the standard converging-diverging slit nozzle. Furthermore the utilization of hot gas gave a promising outcome: the powder size distribution is narrowed and the gas consumption reduced. In the second part of the thesis, the interaction of liquid metal and high speed gas near the feeding tube exit was studied. Both axisymmetric andnon-axisymmetric geometries were simulated using a 3D approach. The filming mechanism was detected only for very small metal flow rates (typically obtained in laboratory scale atomizers). When the melt flow increased, the liquid core overtook the adverse gas flow and entered in the high speed wake directly: in this case the disruption isdriven by sinusoidal surface waves. The process is characterized by fluctuating values of liquid volumes entering the domain that are monitored only as a time average rate: it is far from industrial robustness and capability concept. The non-axisymmetric geometry promoted the splitting of the initial stream into four cores, smaller in diameter and easier to atomize. Finally a new atomization design based on the lesson learned from previous cases simulation is presented.

Chemical synthesis of DNA and RNA containing thio-substituted bases and their post-synthetic modifications

Modified oligonucleotides containing sulphur group have been useful tools for studies of carcinogenesis, protein or nucleic acid structures and functions, protein-nucleic acid interactions, and for antisense modulation of gene expression. One successful example has been the synthesis and study of oligodeoxynucleotides containing 6-thio-2'-deoxyguanine. 6-Thio-2-deoxyguanosine was first discovered as metabolic compound of 6- mercaptopurine (6-MP). Later, it was applied as drug to cure leukaemia. During the research of its toxicity, a method was developed to use the sulphur group as a versatile position for post-synthetic modification. The advantage of application of post-synthetic modification lies in its convenience. Synthesis of oligomers with normal sequences has become routine work in most laboratories. However, design and synthesis of a proper phosphoramidite monomer for a new modified nucleoside are always difficult tasks even for a skilful chemist. Thus an alternative method (post-synthetic method) has been invented to overcome the difficulties. This was achieved by incorporation of versatile nucleotides into oligomers which contain a leaving group, that is sufficiently stable to withstand the conditions of synthesis but can be substituted by nucleophiles after synthesis, to produce, a series of oligomers each containing a different modified base. In the current project, a phosphoramidite monomer with 6-thioguanine has been successfully synthesised and incorporated into RNA. A deprotection procedure, which is specific for RNA was designed for oligomers containing 6-thioguanosine. The results were validated by various methods (UV, HPLC, enzymatic digestion). Pioneer work in utilization of the versatile sulphur group for post-synthetic modification was also tested. Post-synthetic modification was also carried out on DNA with 6- deoxythioguanosine. Electrophilic reagents with various functional groups (alphatic, aromatic, fluorescent) and bi-functional groups have been attached with the oligomers.

Visual performance of the human eye with soft hydrophilic contact lenses

The recording of visual acuity using the Snellen letter chart is only a limited measure of the visual performance of an eye wearing a refractive aid. Qualitative in addition to quantitative information is required to establish such a parameter: spatial, temporal and photometric aspects must all be incorporated into the test procedure. The literature relating to the correction of ametropia by refractive aids was reviewed. Selected aspects of a comparison between the correction provided by spectacles and contact lenses were considered. Special attention was directed to soft hydrophilic contact lenses. Despite technological advances which have produced physiologically acceptable soft lenses, there still remain associated with this recent form of refractive aid unpredictable visual factors. Several techniques for vision assessment were described, and previous studies of visual performance were discussed. To facilitate the investigation of visual performance in a clinical environment, a new semi-automated system was described: this utilized the presentation of broken ring test stimuli on a television screen. The research project comprised two stages. Initial work was concerned with the validation of the television system, including the optimization of its several operational variables. The second phase involved the utilization of the system in an investigation of visual performance aspects of the first month of regular daily soft contact lens wear by experimentally-naive subjects. On the basis of the results of this work an ‘homoeostatic’ model has been proposed to represent the strategy which an observer adopts in order to optimize his visual performance with soft contact lenses.