OAR@UM Collection:

Development and application of validation methods for community pharmacy

Thu, 01 Jan 1998 00:00:00 GMT

Title: Development and application of validation methods for community pharmacy Abstract: The concept of validation, which is today an essential procedure in the area of chemical analysis, was applied to the area of pharmacy practice. The aim of this research study was to develop validation tools which can be used by community pharmacists to monitor the standards of services provided and to measure the impact of the intervention of the pharmacist in a community setting. The validation process is divided into two parts namely the internal validation study where measurement of standards is undertaken from within the profession and the external validation study where measurement of standards is carried out by consumers and by non-pharmacist members of the health-care team. In order to develop internal validation tools, background studies were carried out to identify professional services for which measurement instruments had to be developed. The background studies consisted of a baseline study and of a field observation study. In the baseline study, data on the services provided from community pharmacies were collected from private community pharmacies (n=184) through a personal visit to all private community pharmacies in Malta (n=189). The field observation study was carried out in 10 community pharmacies selected using stratified random sampling. The investigator visited each pharmacy and in total 1800 minutes of pharmacist time were observed. Using the data obtained in the field observation study the Quantitative Community Pharmacy Model was developed from which the internal validation tools to be established were elicited. Five internal validation tools were developed namely The Setting of the Community Pharmacy, Dispensing a Prescription, Responding to Symptoms, Communicating with the Patient and Equipment and Professional Services available in a Community Pharmacy. Local systems and established international guidelines were used to identify indicators of good pharmacy practice which in tum were used to develop the tools. Face and content validity of the internal validation tools were assessed by setting up a group of expert judges with mixed expertise. Inter- observer reliability of the five internal validation tools was assessed. The five internal validation tools were applied by the investigator and another rater in the ten community pharmacies which were randomly selected for the field observation study. Factor analysis was carried out using Biomedical Data Package software version 7.0. Face and content validity of the five internal validation tools were found to be strong. The correlation coefficient for the overall score obtained by the two raters for each tool was high (rs >0.70) indicating consistency of scoring of the tools by different raters. Internal consistency was high (Cronbach's alpha >0.80) for the five internal validation tools. For the external validation process, two external validation tools were developed, namely the Consumer Services Tool directed at consumers and the Health Professionals Tool directed at non-pharmacist members of the health-care team. Face and content validity of the external validation tools were assessed using the same expert judges involved with the review of the five internal validation tools. The test-retest method was adopted to assess the reliability of the two external validation tools. The Biomedical Data Package Software version 7.0 was used to carry out factor analysis. Face and content validity of the two external validation tools were found to be strong. The correlation coefficient for the overall score for test 1 and 2 for each tool was high (rs >0.95) indicating reliability of the two tools. Internal consistency was found to be high (Cronbach's alpha >0.95) for both external validation tools. A standardised protocol for the implementation of the process of validation of community pharmacy was prepared. A pilot test was carried out in 50 community pharmacies selected using stratified random sampling. Areas where these pharmacies need to upgrade the professional services provided were identified. The study revealed that consumers had a good perception of the community pharmacist and that they are satisfied with the services provided while non-pharmacist members of the health-care team were aware of the need to improve professional services provided by the community pharmacist. This research project led to the development and to the psychometric evaluation of validation tools which can be used to monitor standards of professional services provided by the community pharmacist. The validation tools are intended to serve as benchmark procedures in different countries so that international harmonisation of instruments used to measure the effectiveness of the pharmacist in a community setting is achieved. Description: PharmD

Memory performance in a novel ten-compartment water maze: normal behaviour and chlordiazepoxide-induced place learning impairment in rats

Thu, 01 Jan 1998 00:00:00 GMT

Title: Memory performance in a novel ten-compartment water maze: normal behaviour and chlordiazepoxide-induced place learning impairment in rats Abstract: The primary aim of this study was to develop a novel water maze in which the role of extramaze and intramaze cues in the acquisition, storage and retrieval of a place learning task could be evaluated. Animals were not impaired in their ability to locate the submerged escape platform irrespective of whether extramaze cues were present or not in the initial training, even when the starting compartment was rotated to a different location. The results of this study further demonstrated that rats trained in the presence of both sets of cues had considerable exploratory behaviour and a more flexible swim path trajectory, but were more prone to interfering factors on being presented with a new escape response in the absence of extramaze cues. Moreover, it would appear that the animals were able to acquire both mapping and non-mapping strategies during the place learning task and the use of this particular water maze is important in studying the different roles played by intra and extramaze cues during place learning and retrieval. In order to verify whether this particular water maze could be used to study drug induced memory impairment similar to previously developed water mazes, the effect of the benzodiazepine receptor agonist chlordiazepoxide (CDP) on the acquisition and retention of a place learning task in the presence or absence of extramaze cues was investigated. Rats (n=70) were first trained to swim and locate a submerged escape platform placed in one of the compartments of the water maze. They were then divided into two groups of five subgroups each and administered chlordiazepoxide at a dose of 0 (control), 2, 4, 8 and 16 mglkg and tested with a new escape response. All subgroups were then reversed on saline and a new platform location tested. Chlordiazepoxide, in a dose-dependent manner, produced an impairment in the acquisition of new platform location, but only in the presence of extramaze cues. The observed chlordiazepoxide induced memory impairments were completely reversed when the drug was substituted by the vehicle. These results, in agreement with other studies, emphasise the importance of benzodiazepine receptors in the consolidation of place learning tasks, especially in the presence of distal spatial cues. The ease with which the ten-compartment water maze can be configured to measure learning in the presence or absence of extramaze cues together with its ability to dissociate non-mnemonic from mnemonic processes adds an important tool in the study of learning and memory. Description: M.PHIL.

Molecular pathology of infantile GM1 gangliosidosis

Thu, 01 Jan 1998 00:00:00 GMT

Title: Molecular pathology of infantile GM1 gangliosidosis Abstract: The lysosomal storage disorder GM1 gangliosidosis is a genetic neurological disorder caused by a complete or partial deficiency of acid β-galactosidase; it is usually classified as being of infantile, juvenile or adult forms. Infantile GM1 gangliosidosis is relatively common in the Maltese population, with a heterogeneous incidence of 3.3 % and 0.027 % heterozygotes. The molecular lesion associated with this pathology, was studied in two unrelated Maltese families. Fragments containing all the exons and flanking regions of the β-galactosidase gene, were amplified using Polymerase Chain Reaction and then sequenced. A variant was identified and denoted Spl 7. This double point mutation, CA->GT, lies within the IVS 7 of β-galactosidase gene, at position 9 and 10 bp downstream of the 3' end of exon 7, the 3' end is at cDNA position 842. Taq I restriction enzyme digestion, confirmed this mutation. In addition Bfal restriction enzyme digestion, also confirmed the presence of the two mutations in Cis. This variant was confirmed to be non-polymorphic by Taq I digestion of a 100 random chromosomes. Other variants are present in the Maltese population, but they were not characterised in this study. Urinary oligosaccharides analysis was used to test Maltese families for the presence high amount of oligosaccharides, comparing the level of the resulted patterns with the location of maltotetraose (G4). The result was consistent with the molecular study. Description: M.PHIL.

Clinical and molecular pathology of the β+ IVSI-6C thalassaemia in Malta

Thu, 01 Jan 1998 00:00:00 GMT

Title: Clinical and molecular pathology of the β+ IVSI-6C thalassaemia in Malta Abstract: CLINICAL AND MOLECULAR PATHOLOGY OF THE β+ IVSI-6C THALASSAEMIA IN MALTA The main objectives of this study were to characterise the β -thalassaemia mutations present in Malta, evaluate treatment protocols, study the correlation between the genotypical and phenotypical pictures, evaluate the criteria for the proper identification of thalassaemia heterozygotes and investigate the causes for the bone disease in thalassaemia homozygotes. Data on the molecular defects leading to β -thalassaemia were obtained from 28 homozygotes out of the known 29 subjects. Four different mutations were encountered, with the β+IVSI-6(T->C) accounting for 71.4% of all β-thal alle1es [β+IVSI-110(G->A) = 12.5%; β °IVSII-1 (G->A) = 10.7%; β °Codon 39(C->T) = 5.4%]. The β+IVSI-6 (C) allele was present on both haplotype VI and VII while the β °Codon 39(T)and the β+IVSI-110(A) were associated with haplotypes I and IX respectively. The β °IVSII-1(A) mutation was found within haplotype III except in one case that had an unusual VI/Ill hybrid haplotype. The VI/Ill hybrid haplotype was characterised by a low HbF (7.7%) in contrast to the other 5 cases that had a high HbF (-60%). Data collected prospectively on the β+IVSI-6C homozygote children, indicated that the disease presented as a moderate to severe condition needing regular blood transfusions (mean = 70ml/kg/year) for normal growth and development. Splenectomy had little effect on the blood transfusion requirement of the β+IVSI-6C homozygotes. On the other hand, the adult 13+ rvSI-6C homozygous condition was characterised by a mild disease (mean Hb= 8.2g/dl) with only occasional transfusions. Intra-allelic heterogeneity in the level of HbF was observed among the β+IVSI-6C homozygotes and these could be divided into two groups, one with a relatively high HbF (mean=15.0%) and one with a low HbF (4.5%). Statistically significant (p<0.05) gender difference in the level of HbF was also observed with female patients having in general, a higher HbF level. The high incidence of a relatively mild mutation and the presence of iron deficiency amongst the population, posed problems in the proper identification of β-thalassaemia heterozygotes. Indeed 37% (N=19) of obligate β+IVSI-6C heterozygotes had an MCV<80fl and a HbA2 between 3.0 and 3.5%. In an attempt to improve in the identification of the β+IVSI-6C heterozygotes, while keeping the cost of population testing to a minimum, a new approach in the identification of individuals at risk was evaluated with a computed index (10 X RBC3 x HbA²1Hb3) The exclusion of iron deficiency was further considered with a revised discriminant/cut-off value for serum ferritin, which was quite higher than that employed so far. A definite diagnosis amongst those individuals deemed at risk would be obtained by DNA analysis for the prevalent mutation within the population. Osteopenia as documented by a low bone mineral density using DEXA, was present in the majority of the homozygote subjects and was apparent as early as 5 years of age, despite a seemingly adequate hypertransfusion regime. In an attempt to elucidate possible causes for the observed osteopenia, the level of bone biochemical markers for bone formation (serum procollagen I carboxyterminal propeptide and osteocalcin) and for bone turnover (urinary deoxypyridinoline crosslinks and serum tartrate resistant acid phosphatase) were measured amongst the thalassaemia patients. The low serum osteocalcin level accompanied by normal levels for urinary deoxypyridinoline crosslinks and serum procollagen I carboxyterminal propeptide indicated that lack of proper mineralisation could result in the osteopenia observed within this group of patients. Nutritional deficiencies associated with low body weight might be possible causes of the lack of mineralisation among the patients with "mild" alleles. Description: PH.D.