[Attitudes and opinions of general practitioners and lung specialists about a new medicines counselling service for asthma patients in community pharmacies: a qualitative study]. / Points de vue des medécins généralists et des pneumologues sur l'entretien d'accompagnement de novuvelle médication pour les patients asthmatiques: une enquête qualitative.

INTRODUCTION: Since October 2013, pharmacists can offer a new medicines counselling service (NMC). to asthma patients, who start a treatment with an inhaled corticosteroid. Although this individualized service can be organized at the request of the general practitioner (GP). the patient or the pharmacist, the uptake remains quite low. The limited involvement of GPs has already been identified as one of the obstacles to the successful implementation of this project. OBJECTIVE: To explore the attitudes and opinions of GPs and pulmonologists about NMC. METHOD: Focus group discussions with GPs were organized during eight meetings of local quality groups in the province of Antwerp, at which a total of 72 physicians were present. Also, five pulmonologists and two GPs with expertise in organization of primary healthcare participated in an interview. RESULTS: A large group of GPs was not aware of the existence of NMC and only a small number of them had experience with it. Nearly all pulmonologists and GPs agreed that repetition of the inhalation technique and follow-up of the adherence are useful. However, there was disagreement about the importance of taking the Asthma Control Test and explaining the pathology by the pharmacist. We could find five barriers that made physicians withhold support for the NMC. The most important obstacle seemed to be that the pharmacist is not obligated to communicate with the physician about the service. In addition, mainly GPs believed that the remuneration is too high and too focused on the number of NMC services performed and that pharmacists enter their domain with delivering this service. Both pulmonologists and GPs were concerned about how the pharmacist will include patients in a NMC, because it isn't always clear what the indication is of the prescribed inhaled corticosteroid. Furthermore, everyone was convinced that the inclusion criteria should be extended, since each patient using inhalation therapy, would benefit from additional support. Finally, some physicians had an objection to the fact that pharmacists are not obliged to follow an additional course before providing the service. CONCLUSION: The opinions of GPs about NMC were mixed and rather critical, while pulmonologists were somewhat more enthusiastic about the initiative. Although all physicians agreed that there is room for improvement of the concept, some GPs are willing to prescribe BNM for certain patients.

[Drug related problems in Belgian community pharmacies]. / Les problèmes liés aux médicaments dans les officines belges.

INTRODUCTION: The identification, the management and if possible the prevention of drug related problems (DRP), are the main responsibilities of pharmacists. AIM: The aims of the study were 1/to investigate the frequency and nature of drug related problems detected by community pharmacists, 2/to inventories the frequency and nature of the interventions by community pharmacists on prescribed medicines, and 3/to evaluate whether there is a difference between DRP detection at the moment of dispensing versus in a quiet setting (a posteriori detection). METHOD: All trainees of the participating universities of Belgian were asked to contribute to a observational study. Participating pharmacists quantified DRP's and their interventions on prescribed medicines for 5 days. Registrations were made by using a web tool based on an adapted version of the classification list of PCNE. The registration took place in two phases, at the time of delivery as well as in an a posteriori verification of the prescriptions with the pharmaceutical record file of the patients. RESULTS: The study was conducted from November 2012 to April 2013 in 534 community-pharmacies with internship. During this period 9.869 prescriptions (15%) with at least one DRP were detected on a total of 64.962 prescriptions treated by tutor pharmacists. Since there could be more than one problem on a prescription, 15.952 DRP's were registered. 2.597 of the DRP's were detected by a posteriori verification. 75% of all problems had a technical cause and 37% were clinical in nature. Under the technical causes an incomplete prescription was the most common. The most frequently registered clinical causes were a drug interaction, an inopportune time of intake, a too high or too low dose and an unsuitable drug. Participating pharmacists solved almost 3 of the 4 detected DRP's. In more than half of the DRP's, the patient was verbally and/or written informed. In 44% of the a posteriori discovered problems, the pharmacist intervened. CONCLUSION: Pharmacist detected one or more DRP's with 15% of the prescriptions. Analysis of a prescription prior to dispensing the medicines therefore appears necessary. The active intervention of the pharmacist in 83% of the problems indicates that he contributes to the optimization of drug therapy with a potential increase in the quality of life of the patient and a reduction in the cost of healthcare. The a posteriori discovered DRP's demonstrate the need for pharmacist lead meditation reviews possibly together with the physician and/or patient.

[Opinions and attitudes of Flemish pharmacists and general practitioners towards INN prescribing. A survery in Antwerp and East Flanders]. / Avis et attitudes des pharmaciens et des médecins généralistes vis-à-vis de la prescription en DCI. Enquête réalisée à Anvers et en Flandre Orientate.

INTRODUCTION: Since 2002 in Belgium, physicians are allowed to prescribe by International Non-proprietary Name (INN). In 2005, the conditions for this decree were set. Examples from other countries have shown that INN prescribing can significantly contribute to controlling pharmaceutical expenditures. The share of INN prescriptions remains low in Belgium (7% in 2011). OBJECTIVE: To formulate an answer to the question: what are the opinions and attitudes of pharmacists and general practitioners [GP's] with regards to INN prescribing? METHOD: In the winter of 2011-2012, a questionnaire with closed-ended questions was send to pharmacists and GP's in the provinces of Antwerp and East-Flanders, through training days and personal visits. Pharmacists and GP's scored a list of statements with a 5-point Likert scale. The themes of the statements related to: delivering INN prescriptions, legislation, impact on expenditures, choices regarding patient concerns and interprofessional relations. RESULTS: In total, 353 questionnaires were completed and returned of which 228 165%1 were by pharmacists and 125 (35%1 by GP's. Although both declared to be sufficiently up to date with regulations to prescribe (84%) or to deliver (95%] a INN prescription, only 13% of the pharmacists said all prescription they receive contain the correct information. Less GP's [36%) than pharmacists (82%] feel aided by their software program when prescribing or delivering an INN prescription. GP's rely mostly on NIHDI (National Institute for Health and Disability Insurance) as the main source for information on INN prescribing, pharmacists rely on the [Local) pharmacists association. The pharmacists and GP's in the study who relied on NIHDI as main information source, were less aware of legislation concerning INN [N2, p<0,05] than those who rely on the local professional association [N2, p<0,0001]. All pharmacists in the study said to consider the patients medication history when delivering an INN prescription for chronic treatment. However, 57% of the GP's preferred not to prescribe by INN for the reason that they are not sure whether the pharmacist will always consider the patients medication history in case of an INN prescription. Although the GP's showed certain motivation to prescribe by INN, it was no greater than for generic prescribing. And INN prescribing has no added value compared to generic prescribing, according to the GP's. For the pharmacists, INN prescribing does contain an opportunity. With the increase in numbers of dosages and sorts of packaging of generic products, it becomes more and more difficult for pharmacists to manage their stock. In case of an INN prescription, the pharmacist can choose between the different packages in his stock. This offers opportunities especially for acute conditions. CONCLUSION: INN prescribing is a good example of where the collaboration between pharmacists and GP's still contains a lot of opportunities, as well for the two professions, as the government and the patient in terms of controlling the pharmaceutical expenditures. Also the education for pharmacist or GP can further contribute to the sensitization of INN prescribing. In practice, there remain a number of issues and differences in opinions between pharmacists and general practitioners regarding INN prescribing. GP's feel few motivation to prescribe by INN and the government has put no imperative demands towards prescribers. Further evaluation of the practicaL feasibility of the current conditions for prescribing and delivering INN prescriptions is needed.

Potential impact of policy regulation and generic competition on sales of cholesterol lowering medication, antidepressants and acid blocking agents in Belgium.

BACKGROUND: Pharmaceutical expenditures are increasing as a proportion of health expenditures in most rich countries. Antidepressants, acid blocking agents and cholesterol lowering medication are major contributors to medicine sales around the globe. METHODS: We aimed to document the possible impact of policy regulations and generic market penetration on the evolution of sales volume and average cost per unit (Defined Daily Doses and packages) of antidepressants, acid blocking agents and cholesterol lowering medication. We extracted data from the IMS health database regarding the public price and sales volume of the antidepressants (selective serotonin reuptake inhibitors (SSRI's), monoamine oxidase inhibitors (MAOl's) and tricyclic and remaining antidepressants (TCA's)), acid blocking agents (proton pump inhibitors (PPl's) and H2 receptor antagonists) and cholesterol lowering medication (statins and fibrates) in Belgium between 1995 and 2009. We describe these sales data in relation to various national policy measures which were systematically searched in official records. RESULTS: Our analysis suggests that particular policy regulations have had immediate impact on sales figures and expenditures on pharmaceuticals in Belgium: changes in reimbursement conditions, a public tender and entry of generic competitors in a reference pricing system. However, possible sustainable effects seem to be counteracted by other mechanisms such as marketing strategies, prescribing behaviour, brand loyalty and the entry of pseudogenerics. It is likely that demand-side measures have a more sustainable impact on expenditure. CONCLUSION: Compared with other European countries, generic penetration in Belgium remains low. Alternative policy regulations aimed at enlarging the generic market and influencing pharmaceutical expenditures deserve consideration. This should include policies aiming to influence physicians' prescribing and a shared responsibility of pharmacists, physicians and patients towards expenditures.

[Critical evaluation of interaction screening software available in pharmacies]. / Evaluation critique des logiciels d'interactions médicamenteuses a l'officine.

Due to the increasing complexity of medication regimens it is not always easy for the pharmacist to quickly and effectively screen the drug use of a particular patient for interactions. By means of a survey and a comparison, the advantages and disadvantages of the most common software packages available in Flanders were analysed. Major stumbling blocks of the currently available software are the high number of false positive signals, the absence of a history regarding the management of interactions, the lack of timely updates of the database and the absence of clear guidelines for the management of an interaction. Based on this research, we make the following recommendations: (1) signal fatigue should be reduced by interaction screening based on the duration of therapy in addition to the ability to suppress signals, (2) a log, coupled with the prescription-register, should be implemented, (3) software companies should help pharmacists more in configuring software preferences and provide them with better information bout the available options, (4) the underlying databases must be updated more quickly. (5) OTC medications, especially in the context of polypharmacy, should be registered in the patient record by the pharmacist, (6) note that food supplements are not included in the interaction screening software, unlike registered medication. (7) the knowledge of pharmacists regarding interactions should be maintained and improved.

[Pharmaceutical care of heart failure: theory and clinical practice]. / Les soins pharmaceutiques de l'insuffisance cardiaque chronique: la théorie et la pratique.

Heart failure is a serious, progressive and chronic illness that affects an ever-growing part of the population. Heart failure has a bad prognosis: only 50% of patients are still alive five years after the diagnosis. It is important to improve this outcome and the pharmaceutical care of these patients is therefore a priority for pharmacists. In the present study we investigated the differences between theory and clinical practice in order to identify opportunities to improve the pharmaceutical care of the heart failure patient. We showed that the knowledge of the pharmacist concerning heart failure is still insufficient. A typical heart failure prescription often goes unrecognized and many NSAIDs are dispensed (to approximately 1 out of 4 heart failure patients, also for longer time periods), even though these drugs are contraindicated. Our study of medication reviews demonstrated that NSAIDs are often prescribed for heart failure patients by non-cardiologists. The outcome of this research indicates that a substantial improvement of the pharmaceutical care of heart failure patients is possible and needed.

Structure of apolipoprotein B-100 in low density lipoproteins.

There is general consensus that amphipathic alpha-helices and beta sheets represent the major lipid-associating motifs of apolipoprotein (apo)B-100. In this review, we examine the existing experimental and computational evidence for the pentapartite domain structure of apoB. In the pentapartite nomenclature presented in this review (NH(2)-betaalpha(1)-beta(1)-alpha(2)-beta(2)-alpha(3)-COOH), the original alpha(1) globular domain (Segrest, J. P. et al. 1994. Arterioscler. Thromb. 14: 1674;-1685) is expanded to include residues 1;-1,000 and renamed the betaalpha(1) domain. This change reflects the likelihood that the betaalpha(1) domain, like lamprey lipovitellin, is a globular composite of alpha-helical and beta-sheet secondary structures that participates in lipid accumulation in the co-translationally assembled prenascent triglyceride-rich lipoprotein particles. Evidence is presented that the hydrophobic faces of the amphipathic beta sheets of the beta(1) and beta(2) domains of apoB-100 are in direct contact with the neutral lipid core of apoB-containing lipoproteins and play a role in core lipid organization. Evidence is also presented that these beta sheets largely determine LDL particle diameter. Analysis of published data shows that with a reduction in particle size, there is an increase in the number of amphipathic helices of the alpha(2) and alpha(3) domains associated with the surface lipids of the LDL particle; these increases modulate the surface pressure decreases caused by a reduction in radius of curvature. The properties of the LDL receptor-binding region within the overall domain structure of apoB-100 are also discussed. Finally, recent three-dimensional models of LDL obtained by cryoelectron microscopy and X-ray crystallography are discussed. These models show three common features: a semidiscoidal shape, a surface knob with the dimensions of the betaC globular domain of lipovitellin, and planar multilayers in the lipid core that are approximately 35 A apart; the multilayers are thought to represent cholesteryl ester in the smectic phase. These models present a conundrum: are LDL particles circulating at 37 degrees C spheroidal in shape, as generally assumed, or are they semidiscoidal in shape, as suggested by the models? The limited evidence available supports a spheroidal shape.

A detailed molecular belt model for apolipoprotein A-I in discoidal high density lipoprotein.

Apolipoprotein A-I (apoA-I) is the principal protein of high density lipoprotein particles (HDL). ApoA-I contains a globular N-terminal domain (residues 1-43) and a lipid-binding C-terminal domain (residues 44-243). Here we propose a detailed model for the smallest discoidal HDL, consisting of two apoA-I molecules wrapped beltwise around a small patch of bilayer containing 160 lipid molecules. The C-terminal domain of each monomer is ringlike, a curved, planar amphipathic alpha helix with an average of 3.67 residues per turn, and with the hydrophobic surface curved toward the lipids. We have explored all possible geometries for forming the dimer of stacked rings, subject to the hypothesis that the optimal geometry will maximize intermolecular salt bridge interactions. The resulting model is an antiparallel arrangement with an alignment matching that of the (nonplanar) crystal structure of lipid-free apoA-I.

The amphipathic helix in the exchangeable apolipoproteins: a review of secondary structure and function.

Site-directed mutagenesis and other molecular biology-based techniques are now available for probing the amphipathic alpha helix structural motif in the exchangeable apolipoproteins. Here we survey the published literature on lipid-binding and functional domains in apolipoproteins A-I, A-II, A-IV, C-I, C-II, C-III, and E and compare these results with recently developed computer methods for analysis of the location and properties of amphipathic helixes. This comparison suggests that there are at least three distinct classes of amphipathic helixes (classes A, Y, and G*) in the exchangeable apolipoproteins whose distribution varies within and between the seven apolipoproteins. This comparison further suggests that lipid affinity resides largely in class A amphipathic helixes (Segrest, J. P., et al. 1990. Proteins. 8: 103) and that variations in structure and/or numbers of class A domains in individual apolipoproteins allow a range of lipid affinities from high to low. The positions of the four alpha helixes recently shown to form a 4-helix bundle globular structure in apoE (Wilson, C., et al. 1991. Science. 252: 1817) correspond closely to the four amino-terminal class G* amphipathic helixes of apoE identified by our computer analysis. It is of particular interest, therefore, that all of the exchangeable apolipoproteins except apoA-II and C-I, contain amphipathic helixes of class G*. Additional implications of amphipathic helix heterogeneity for the structure and function of the exchangeable apolipoproteins will be discussed.

Mean field stochastic boundary molecular dynamics simulation of a phospholipid in a membrane.

Computer simulations of phospholipid membranes have been carried out by using a combined approach of molecular and stochastic dynamics and a mean field based on the Marcelja model. First, the single-chain mean field simulations of Pastor et al. [(1988) J. Chem. Phys. 89, 1112-1127] were extended to a complete dipalmitoylphosphatidylcholine molecule; a 102-ns Langevin dynamics simulation is presented and compared with experiment. Subsequently, a hexagonally packed seven-lipid array was simulated with Langevin dynamics and a mean field at the boundary and with molecular dynamics (and no mean field) in the center. This hybrid method, mean field stochastic boundary molecular dynamics, reduces bias introduced by the mean field and eliminates the need for periodic boundary conditions. As a result, simulations extending to tens of nanoseconds may be carried out by using a relatively small number of molecules to model the membrane environment. Preliminary results of a 20-ns simulation are reported here. A wide range of motions, including overall reorientation with a nanosecond decay time, is observed in both simulations, and good agreement with NMR, IR, and neutron diffraction data is found.

Role of amphipathic helixes in HDL structure/function.

In a recent analysis we classified amphipathic helix domains into a minimum of seven distinct classes. Four amphipathic helix classes are found in lipid-associating proteins: apolipoproteins, certain polypeptide hormones, polypeptide venoms and antibiotics, and certain complex transmembrane proteins. Three amphipathic helix classes are involved in both intra- and intermolecular protein-protein interactions: calmodulin-regulated protein kinases, coiled-coil containing proteins that include the so-called leucine zipper, and globular helical proteins. Three central hypothesis have been developed in our studies of the apolipoprotein class of amphipathic helixes: 1) The "Snorkel" hypothesis proposes that when the amphipathic helix is associated with phospholipid, amphipathic basic residues extend toward the polar face of the helix to insert their charged residues into the aqueous milieu: thus the entirety of the uncharged van der Waals' surface of the amphipathic helix is buried within the lipid. 2) We have formulated a hypothesis that Glutamyl residues located at positions 78 and 111 in apolipoprotein A-I on the nonpolar face of two amphipathic helical domains are critical to LCAT activation. 3) The hinged-domain hypothesis was proposed to explain the structural basis for the quantization of HDL subspecies, protein-protein interactions in HDL, and the HDL disc to sphere transformation.

Charge distributions and amphipathicity of receptor-binding alpha-helices.

Contacts between ligands and cell-surface receptors result in cellular activation. Defining principles which govern these important interactions are of interest and might facilitate pharmacologic intervention. We examined receptor-binding alpha-helical segments of polypeptide hormones and globular proteins for distinguishing amino acid content and distributions. There was a slight excess of basic residues in both sets of alpha-helices compared with a panel of control helices. Helical concentrations of charged residues were quantitated using the hydrophobic moment algorithm, adapted to obtain the vector sum of side chain charges. By this analysis we detected increased concentrations of the set of basic residues (arginine, lysine and histidine) on one side of the receptor-binding alpha-helices of the polypeptide hormones, and to a lesser extent the protein ligands. Comparable data were obtained for "lytic" venom peptides and calmodulin-regulated kinase segments. There was an even greater correlation between receptor-associating alpha-helical segments and large hydrophobic moments. Receptor-binding helical segments of polypeptide hormones, and to a lesser extent those of protein ligands, often are basic and amphipathic.

Identification of peptide hormones of the amphipathic helix class using the helical hydrophobic moment algorithm.

Eisenberg's helical hydrophobic moment (less than mu H greater than) algorithm was applied to the analysis of the primary structure of amphipathic alpha-helical peptide hormones and an optimal method for identifying other peptides of this class determined. We quantitate and compare known amphipathic helical peptide hormones with a second group of peptides with proven nonamphipathic properties and determine the best method of distinguishing between them. The respective means of the maximum 11 residue less than mu H greater than for the amphipathic helical and control peptides were 0.46 (+/-/-0.07) and 0.33 (0.07) (P + 0.004). To better reflect the amphipathic potential of the entire peptide, the percent of 11 residue segments in each peptide above a particular less than mu H greater than was plotted vs less than mu H greater than. The resulting curves are referred to as HM-C. The mean HM-C (of the two groups) was highly significantly different such that the HM-C method was superior to others in its ability to distinguish amphipathic from nonamphipathic peptides. Several potential new members of this structural class were identified using this approach. Molecular modeling of a portion of one of these, prolactin inhibitory factor, reveals a strongly amphipathic alpha helix at residues 4-21. This computer-based method may enable rapid identification of peptides of the amphipathic alpha-helix class.

Conformational analysis of lipid-associating proteins in a lipid environment.

Two major types of helical structures have been identified in lipid-associating proteins, being either amphipathic or transmembrane domains. A conformational analysis was carried out to characterize some of the properties of these helices. These calculations were performed both on isolated helices and in a lipid environment. According to the results of this analysis, the orientation of the line joining the hydrophobic and hydrophilic centers of the helix seems to determine the orientation of the helix at the lipid/water interface. The calculation of this parameter should be useful to discriminate between an amphipathic helix, parallel to the interface and a transmembrane helix orientated perpendicularly. The membrane-spanning helices are completely immersed in the phospholipid bilayer and their length corresponds to about the thickness of the hydrophobic core of the DPPC bilayer. The energy of interaction, expressed per phospholipid is significantly higher for the transmembrane compared to the amphipathic helices. For the membrane-spanning helices the mean energy of interaction is higher than the interaction energy between two phospholipids, while it is lower for most amphipathic helices. This might account for the stability of these protein-anchoring domains. This computer modeling approach should usefully complement the statistical analysis carried out on these helices, based on their hydrophobicity and hydrophobic moment. It represents a more refined analysis of the domains identified by the prediction techniques and stress the functional character of lipid-associating domains in membrane proteins as well as in soluble plasma lipoproteins.

Immunochemical characterization of two antigenic sites on human apolipoprotein A-I; localization and lipid modulation of these epitopes.

Two monoclonal antibodies, A17 and A30, were raised against human apolipoprotein A-I (apo A-I). They were studied by competitive inhibition of 125I-labeled HDL3 with HDL subfractions, delipidated apo A-I, and complexes of dimyristoylphosphatidylcholine (DMPC) containing apo A-I and apo A-II. Immunoblotting located the A17 antibody on CNBr fragment 4 of apo A-I and the A30 antibody on CNBr fragment 1. The A17 antigenic determinant was expressed identically in all HDL subclasses, on delipidated apo A-I as well as all on the DMPC-apo A-I and DMPC-apo A-I/apo A-II complexes. In contrast, the apparent affinity constant of the A30 antibody for delipidated apo A-I was about 30-times less than for HDL3 or for apo A-I/apo A-II-phospholipid complexes. These data suggest that the association of apo A-I with phospholipids improves the reactivity of the A30 monoclonal antibody towards apo A-I, and that this antigenic determinant has a different conformation in delipidated apo A-I compared to apo A-I complexed with phospholipids. Turbidimetric and fluorescence experiments monitoring the phospholipid-apo A-I association in the presence and in the absence of the A17 and A30 antibodies were consistent with the competition experiments carried out by solid phase radioimmunoassay (RIA). After reaction of apo A-I with the A30 antibody, we observed an enhancement of the degradation kinetics of large multilamellar vesicles (LMV), while the A17 antibody did not have a significant effect. Calcein leakage experiments carried out below the transition temperature of DPPC showed an enhancement of the degradation kinetics with both monoclonal antibodies, while the phase-transition release was independent of the reaction of apo A-I with the monoclonal antibodies. These data therefore suggest the existence of at least two different types of epitope on apo A-I, which might account for the differences in immunological reactivity of apo A-I that is either delipidated or present on HDL.

Structure function relationship of the plasma apolipoproteins: a computational approach based on hydrophobicity characteristics.

Using different hydrophobicity analysis techniques we investigated the structure-function relationship of the different apolipoproteins. Lipid-binding domains were localized and within this class of protein domains, lecithin-cholesterol acyltransferase activating and non-activating amphipathic helices could be differentiated. A hydrophobic moment analysis of the apolipoprotein E sequence yielded interesting data concerning its receptor-binding and heparin binding characteristics. Finally we discuss the amphiphilic helical characteristics of certain domains of the apolipoprotein B sequence.

Human apolipoprotein B: analysis of internal repeats and homology with other apolipoproteins.

Apolipoprotein B (apoB) is the major protein component of plasma low density lipoproteins (LDL) and, through its binding to the LDL receptor, it plays a prominent role in lipoprotein metabolism and in the development of atherosclerosis. Specially developed computer programs were applied to detect potential internal repeats in the human apoB sequence and homology of some of these repeats with other apolipoproteins. The simultaneous computer alignment of several (repeated) sequences, carried out in an iterative way to generate consensus sequences, showed the presence of repeated amphipathic helical regions and of repeated hydrophobic proline-rich domains. Extensive Monte-Carlo statistics were used to demonstrate the statistical significance of the internal repeats. Both classes of repeats may contribute to the specific lipid-binding characteristics of apoB. Additional homology, detected between apoB and apoE, the other apolipoprotein-ligand of the LDL receptor, further defined the structural requirements for this receptor-ligand interaction. The computer programs developed in this study should also be useful for detecting internal repeats in other proteins.

Functional differentiation of amphiphilic helices of the apolipoproteins by hydrophobic moment analysis.

The amphiphilic character of different plasma apolipoproteins was investigated by a combination of established hydrophobicity analysis methods. These methods proved to be powerful in the detection of amphiphilic phospholipid-binding domains. Within this class of lipid-binding domains, lecithin-cholesterol acyltransferase activating and non-activating helices could be differentiated by calculating hydrophobic moments at different angles. We conclude that the hydrophobic characteristics of the different helices determined the mode of lipid binding and the substrate properties of these phospholipid-protein complexes for the lecithin-cholesterol acyltransferase reaction.