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Contains fulltext : 205222.pdf (Publisher’s version ) (Closed access) Direct-acting antivirals (DAAs) are known victims (substrate) and perpetrators (cause) of drug-drug interactions (DDIs). These DAAs are used for the treatment of hepatitis C virus (HCV) infections and are highly effective drugs. Drugs used for cardiovascular risk management are frequently used by HCV-infected patients, whom also are treated with DAAs. Therefore, the aim of this review was to describe DDIs between cardiovascular drugs (CVDs) and DAAs. An extensive literature search was performed containing search terms for the marketed DAAs and CVDs (beta-blocking agents, ACE inhibitors, angiotensin II antagonists, renin inhibitors, diuretics, calcium channel blockers, statins/ezetimibe, fibrates, platelet aggregation inhibitors, vitamin K antagonists, heparins, direct Xa inhibitors, nitrates, amiodarone, and digoxin). In particular, the drug labels from the European Medicines Agency and the US Food and Drug Administration were used. A main finding of this review is that CVDs are mostly victims of DDIs with DAAs. Therefore, when possible, monitoring of pharmacodynamics is recommended when coadministering these drugs with DAAs. Nevertheless, it is sometimes better to discontinue a drug on a temporary basis (statins, ezetimide). The DAAs are victims of DDIs in combination with bisoprolol, carvedilol, labetalol, verapamil, and gemfibrozil. Despite there are many DDIs predicted in this review, most of these DDIs can be managed by monitoring the efficacy and toxicity of the victim drug or by switching to another CVD/DAA.

The specific rotation of lactose has been estimated for wave-lengths 5461 and 5893. The influences of concentration, temperature and pH of the solution have been studied and expressed in new formulae.

Medium-energy ion scattering measurements and Monte Carlo computer simulations have been used to study the melting behaviour of the two open low-index surfaces of indium: In(110) and In(011). Because of the tetragonal lattice structure, the atomic density at the In(110) surface is 3.5% lower than that at the In(011) surface. The corresponding higher surface free energy of the (110) surface is expected to give rise to a slightly stronger surface melting effect at this face than at the (011) face. The ion-scattering measurements indeed show such a difference in melted-layer thickness at temperatures close to the bulk melting point, T m = 429.76 K. Surprisingly, however, the order of the onset of surface disordering is reversed. In(110) starts disordering about 25 K closer to T m than In(011). We attribute this counter-intuitive difference in disordering onset to the difference in adatom-vacancy creation energies at the two surfaces. This idea is corroborated by energy calculations and Monte Carlo computer simulations, in which a Finnis-Sinclair interaction potential between indium atoms was employed. The slightly increased nearest-neighbour distance on the more densely-packed In(011) surface leads to a decreased creation energy of adatoms and vacancies. The resulting higher densities of adatoms and vacancies make In(011) unstable at a lower temperature than In(110). These results strongly suggest that the onset of surface disordering involves a mechanical surface instability.

The atomic structure of Er silicides on Si(111) in the submonolayer range has been studied by means of medium-energy ion scattering and surface x-ray diffraction. We find good agreement between the two techniques. The ion-scattering measurements indicate that the Er adsorbs in a single two-dimensional layer on top of which a completely relaxed (bulklike) Si bilayer is located. This bilayer is exclusively of {ital B} type, i.e., rotated by 180{degree} with respect to the substrate bilayers. The x-ray diffraction results show that Er is positioned on {ital T}{sub 4} sites only, i.e., above second-layer substrate atoms. For low coverages (0.23 ML), the height of the top bilayer appears to be reduced by approximately 0.4 A. We attribute this to the fact that the Er does not form a closed layer, leading to the formation of less ordered Er-Si complexes in which extra Si adatoms provide the backbonds for the Si hexagons on top of the Er. Finally, we investigate the thermal stability of the two-dimensional silicide, and find that the two-dimensional Er layer evolves into relaxed three-dimensional islands at temperatures above 800{degree}C with concomitant strain relaxation. {copyright} {ital 1996 The American Physical Society.}

A growth mode and interface structure analysis has been performed for Ag deposited at a high temperature of 300°C on the HF-treated Si(111):H surface by means of medium-energy ion scattering and elastic recoil detection analysis of hydrogen. The measurements show that Ag grows in the Volmer-Weber mode and that the Ag islands on the surface are epitaxial with respect to the substrate. The preferential azimuthal orientation is A-type only when Ag is deposited slowly. The interface does not reconstruct to the √3 × √3-Ag structure, which is normally observed for Ag deposition above 200°C on the Si(111)7 × 7 surface, but retain bulk-like structure. The presence of hydrogen at the interface is demonstrated after deposition of thick (1100 A) Ag films. However, the amount of hydrogen at the interface is not a full monolayer. This partial desorption of hydrogen from the interface explains why the Schottky barrier heights of Ag Si (111) : H diodes are close to those of Ag Si (111)7 × 7 and Ag Si (111)2 × 1 .

This study presents a contribution to the understanding of the mechanisms that are involved in the development and maintenance of dental anxiety. Subjects were 224 undergraduate psychology students who completed questionnaires regarding dental anxiety, painful and traumatic experiences, negative cognitions, dental beliefs, and how their attitude to dental treatment had changed during their life. The results showed that both the extent to which earlier dental treatments were perceived as painful and the extent to which these incidents were reported as traumatic were significantly related to dental anxiety. Evidence was also found to support the latent inhibition hypothesis, which predicts that patients less easily acquire dental anxiety in case they received a number of relatively painless treatments prior to conditioning. Both findings confirmed those earlier obtained by Davey in a conceptually similar design (Behaviour Research and Therapy, 27, 51–58, 1989). In addition, frequency of negative cognitions about dental treatment and dental anxiety appeared to be positively related (r = 0.74; P < 0.001). Significant differences were found between highly anxious Ss and Ss showing low levels of anxiety on a variety of expectations and beliefs related to undergoing dental treatment. The results are discussed in terms of a cognitive-behavioural perspective of dental anxiety.

Medium-energy ion scattering (MEIS) measurements have been performed on the Si(111) surface which was terminated with hydrogen by means of immersion in a diluted HF solution. The measurements and the fit of Monte Carlo simulations to the experimental data show that the structure of the Si(111):H surface is close to that of a truncated bulk Si lattice. The relaxation of the distance between the top and the second layer, d12, and that between the second and the third layer, d23, are as small as 0.00± 0.04 A ( 0.0 ± 5.1 % ) and −0.04 ±0.04 A ( −1.7 ± 1.7% ), respectively. The measurements further reveal that the average one-dimensional root-mean-square thermal displacement of the two outermost atomic layers is enhanced from the bulk value of 0.075 A to 0.11±0.01A.

This article presents the results of a study among 332 extremely anxious persons who applied for treatment at SBT, a Dutch special dental care clinic, between July 1990 and December 1991. It was found that 85% of these persons actually started treatment. Two and a half years later it appeared that 39% of them still received regular treatment, whereas 34% had completed treatment. Twelve percent stopped visiting before treatment was completed. Furthermore, results showed that dental anxiety was reduced after treatment. However, 36% of the patients still avoided appointments with a dentist. It is concluded that for most of the dentally anxious patients specialized care and oral health are no guarantee for regular dental attendance in the long term.

The short term effects of a dental health educational video on adolescents' knowledge, attitude and future behaviour were assessed. Results showed a large effect on knowledge and a small effect on five attitudinal aspects. No effects were found on future behaviour.

Patients' perceptions play an important role in assessing the quality of dental treatment. This study investigated 56 possible quality aspects on their importance as judged by regular attenders. A nationwide sample of 5000 Dutch people was contracted, 1328 persons meeting our selection criteria filled out the questionnaire and responded. The results show that hygiene of instruments and the availability of the dentist in case of emergency were considered the most important. It was concluded that in general these patients judged technical and functional aspects of dental care to be of more importance than communicative and informative aspects. Differences in perceptions were found according to sex and, to a lesser extent, to education, means of insurance and place of residence. But, on the whole, response patterns were homogeneous.

The aim of this study was to describe to dental health status of a group of Dutch 20-40-yr-old drug addicts (n = 121) and to compare the results if DMFS with data of an age-comparable sample of the general adult population in the Netherlands (n = 1532). Mean DMFT of the addicted group was 16.9. ANOVA showed that the mean DMFS of the addicted group differed statistically significantly from the DMFS of the general population of the same age (= 52.1 versus 38.9) Statistically significant differences in DMFS were also found between the various age groups. The percentage of addicted subjects with more than cervical plaque on one or more teeth was 76.5%m 82.4% and 88.2% in the three youngest age groups. In almost all addicted subjects, bleeding of the gingiva was present Only 36% had visited the dentist less than a year ago and 18% brushed their teeth less than once a day. It is concluded that there is a large gap in dental health status and behavior between drug addicts and the general population. Dental care as an integral part of the care for drug addicts is advocated.

This study investigated whether dental treatment plans and planning of general practitioners are different for addicted and identical non-addicted patients. Dental practitioners (n=500) were sent a questionnaire with information on and questions about treatment for either an addicted or an identical non-addicted patient; response rate was 41%. Loglinear analysis showed that after controlling for the influence of four demographic variables (sex, age, number pf patients and number of National Health Service insured patients), the treatment plans made for addicted patients were less elaborate than those for the non-addicted. For the addicted, fillings or frames were proposed more often, whereas for non-addicted patients more often crowns or bridges were proposed. Extraction instead of filling was more often proposed for the addicted patient. Less elaborate treatment for addicted patients corresponds to the way dentists specialized in treating drug addicts work, with one exception: extraction should be avoided whether a patient is addicted or not. Treatment planning did not differentiate for addicted and non-addicted patients, whereas dentists specialized in treating addicted patients do recommend an adjusted treatment plan for the addicted.

The aim of this study was to describe the dental health status of a group of Dutch twenty- to forty-year-old drug addicts (n = 121) and to compare the results on DMFS with data of an in age comparable sample of the general non-addicted adult population in the Netherlands (n = 1532). The average DMFT of the addicted group was 16.9. The average DMFS of this group differed statistically significantly from the DMFS of the general non-addicted population of the same age (52.1 versus 38.9). Statistically significant differences in DMFS were also found between the various age groups. In the youngest three age groups the percentage of addicted subjects with cervical plaque on one or more teeth was 76.5%, 82.4% and 88.2%. Bleeding of the gingiva occurred in almost all addicted subjects. Only 36% of the addicts had visited their dentist less than a year ago and 18% of them brushed their teeth less than once a day. It is concluded that a large gap exists in dental health status and behaviour between drug addicts and the general non-addicted population. Dental care as an integral part of the care for drug addicts is advocated.

The present study was intended to explore the relationship between individuals' level of dental anxiety and thoughts (both self-statements and mental images) related to dental treatment. Subjects were 210 psychology students (75 males, 135 females). The results showed that 98% of the subjects reported one or more negative or catastrophic thoughts. A significant positive relationship was found between reported severity of anxiety (S-DAI scores) and frequency of thoughts. The results indicate that dental anxiety is associated with the tendency to experience negative or threatening thoughts concerning treatment.

This study investigated the psychometric properties of the Dental Cognitions Questionnaire (DCQ). This measure contains 38 items and assesses both frequency and believability of negative cognitions related to dental treatment. The results indicated that the DCQ has good internal consistency, high test-retest reliability, and satisfactory concurrent validity, as indicated by positive associations with indices of anxiety and other cognitive measures (n = 180). Factor analysis revealed a one factor solution. Furthermore, the DCQ discriminated strongly between dental phobics (n = 85) and non-phobic Ss (n = 70). Moreover, it was found that combinations of DCQ items have substantially more explanatory power than did a measure of dental trait anxiety, explaining up to 70.7% of the variance in state anxiety ratings in the dental situation. Overall, it appears that dental phobics have many extremely negative beliefs and self-statements about themselves and about what might happen during treatment. Since certain cognitions seem to play a critical role in fear evocation, diminishing catastrophizing ideation may be an important determinant of adjustment to dental treatment and reduction of psychological distress.

Reasons for drug addicts' non-compliance to dental referral were investigated. Sixty-eight out of 83 addicts referred to the dentist were interviewed. Eighty-one percent intended to go, but only 42% did show up for their first appointment. Mean dental anxiety score (SDAI) was 23.6. An active referral of a non-anxious patient who visited the dentist in the past if in pain appeared least likely to fail. Dental care as an integral part of care for drug addicts is advocated.

The atomic structure of thin epitaxial erbium suicides on Si(111) substrates has been studied in situ by means of surface X-ray diffraction and medium-energy ion scattering. In the sub-monolayer range, a two-dimensional (2D) suicide is formed within a 1 × 1 unit cell, with the Er atoms occupying T4 sites and a Si bilayer on top which is 180° rotated with respect to the bulk (5-type). Suicide layers with a thickness of 3 monolayers exhibit a regular network of Si vacancies which release the compressive strain of the graphite-like Si layers between adjacent Er layers. This results in a √3 × √3 R 30° unit cell, in which 3 out of 5 Si atoms are displaced towards the vacancy, and in which 3 Er atoms relax away from the vacancy.

This study examined cognitive correlates of dental anxiety among 24 highly anxious patients and 17 low-anxious patients. In both groups, anxiety expectations, dental trait anxiety, and state anxiety (in the waiting room and in the dental chair) were rated. Negative cognitions and cognitive control were also assessed. It was found that dentally high-anxious patientsclaimed toexperience more negative thoughts than those with low anxiety (p < 0.001). None of the highly anxious patients reported relatively few negative cognitions, and none of the patients in the low-anxiety group reported relatively numerous negative cognitions. While patients from both groups reported that cognitive control declined with the imminence of treatment, highly anxious patients were found to have less control over their negative thoughts (p < 0.001). A series of stepwise regression analyses revealed that both the number of negative cognitions and perceived cognitive control accounted for 75% of the variance in dental trait anxiety. The results of the present study suggest that cognitive activities, such as negative thinking (catastrophizing) and cognitive control, are important moderators of dental anxiety.

In this study it was found that dental phobics with a high monitoring coping style (n = 12) indicated themselves as being less able to control cognitions about an upcoming treatment than phobics with a low monitoring coping style (n = 12). In addition, high monitoring phobics neither reported higher levels of state anxiety in anticipation of treatment nor had more negative cognitions about the upcoming treatment. An additional finding was that, compared to low anxious patients, dental phobics exhibited higher monitoring scores, but only on the dentist situation of the Miller Behavioural Style Scale and not on the three other situations of this questionnaire.

A questionnaire on the recognition and reporting of child abuse was sent to a random sample of Dutch dental practitioners (N = 250). The response rate was 54%. Eighty-six percent had never seen a case of child abuse. The percentage of dentists reporting a (suspicious) case of child abuse (6%) was lower than the percentage of dentists detecting a case of suspicious child abuse (14%). The most important reason for this discrepancy seems to be a lack of knowledge and/or skills to properly identify child abuse. More professional education about child abuse is desired.

A review is presented of the behavioural research in dentistry published in or after 1987 on dental anxiety, dentist-patient relationship, compliance and dental attendance. It is concluded that little progress has been made in the field of behavioural dentistry during those years and recommendations are made to improve future research efforts.

A previous study has shown five-year-old children of parents originating from Turkey or Morocco to have twice as much dmfs as children of parents from The Netherlands, Surinam or various other countries. In the present study, other risk indicators and factors for the prevalence of caries amongst these children were studied by interviewing their parents at home in their mother tongue about their preventive dental behaviour. Results showed educational level of the parents, and gender of the child to be important risk indicators, apart from ethnicity. Risk factors were the age of the child, at which the parents had started to brush the teeth of the child, the use of fluoride tablets and the regularity of the brushing behaviour.

The aim of this study was threefold: first, to assess the oral health of Turkish, Moroccan, Surinamese, Dutch and "other" 5-yr-old children living in Amsterdam; second, to identify risk indicators for caries, in addition to ethnicity; and third, to identify potential risk factors related to differences in caries experience in these children. Results showed the mean dmfs scores of Turkish and Moroccan children to be much higher than that of the Dutch and Surinamese children; 8.1 and 8.2 versus 3.6 and 3.4, respectively. The educational level of the parents and the gender of the children were important risk indicators, in addition to ethnicity. The age of the child at which the parents had started to brush their child's teeth, the use of fluoride tablets and the regularity of the brushing behavior in the past could be identified as potential risk factors. Chemicals/CAS: fluoride, 16984-48-8; Fluorides

Many people expect dental treatment to be painful. This kind of expectation has important negative consequences for the patients' well-being. Disappointing occurrences during the treatment itself can further influence the expectations about a next treatment. The fact that the treatment result happens to be more positive than expected is a necessary instead of a sufficient condition for changing existing expectations. A cognitive model for dental fear is proposed and some implications for the general practice are discussed.

Four hundred and fifty dental graduates from the Free University (VU), the University of Amsterdam (UvA) or the Academic Center for Dentistry Amsterdam (ACTA) between 1982 and 1990 were asked by questionnaire to give their opinion about the undergraduate dental training they received. Most respondents felt that their undergraduate education prepared them reasonably well for general practice. Yet imperfections in the education were noticed. These imperfections show resemblance to conclusions from similar surveys in other countries.

This article presents the results of an enquiry by telephone of the attainableness and availability of dentists during weekend duty. In 89.5% of the cases a patient can be treated by a dentist he phoned or his substitute within a reasonable period of time. In 10.5% a patient does not obtain a satisfactory solution after telephoning a dentist once.

Supersonic nozzle beams of pure OCS and argon seeded (10% OCS-90% Ar and 5% OCS-95% Ar) were studied. Typical nozzle source conditions were: total backing pressure 0.73 bar, nozzle diameter 60 μm, and nozzle source at room temperature. The translational temperatures of the beams were determined from measured velocity distributions. Intensity measurements of electric resonance transitions of OCS originationg in rotational states up to J = 5 have been used to obtain the rotational tempetrature: 14(4) K for a pure OCS beam and 3.5(7) K for the argon seeded OCS beams. The rotational beam temperatures deduced front the observed rotational energy distributions agree (within experimental uncertainties) with the translational temperatures.

Applied I. Ajzen and M. Fishbein's (1980) attitude-behavior model to the problem of stimulating the demand for dental care with 329 members (aged 21-50 yrs) of health insurance companies who had not received regular dental treatment and/or certificate of dental fitness for at least 2 1/2 yrs. Applying for treatment and acquiring a dental certificate were the behavioral measures. The effectiveness of a message based on Ajzen and Fishbein's model was compared with the effectiveness of messages based on I. M. Rosenstock's (1974) health-belief model and the notion that knowledge of rights and obligations is a prerequisite for seeking dental care. Results support the validity of the Ajzen and Fishbein model. Relationships between the components of the model were moderate to strong, both before and after Ss were exposed to the message. The message proved effective in changing beliefs about seeking dental treatment. Ajzen and Fishbein's claim that their approach has exclusive merits, however, was refuted in that a differential effectiveness of the 3 messages was absent. In all, 47.4% of the Ss applied for treatment. No control Ss applied. 15 mo later, 70% of the applicants had obtained a dental certificate. Contrary to expectations, the no-message, application-form-only condition proved equally effective as the message conditions.

In the year 1986 1910 persons made use of the services of a dental health education center in Amsterdam. One day a week a dentist could be consulted. The rest of the week other members of the team were available for answering questions. Almost 30% of the questions concerned dental treatment, diagnosis of treatment plan, 20% dental fees and other financial aspects of treatment and questions for folders, posters et cetera accounted for another 20%. Only 5% of the questions referred to preventive matters. A quarter of the dentist's interventions consisted of giving a second opinion. More women than men, and more privately insured than sick fund insured contacted the center.

Dentists' opinion on the utility of a dental health education centre was assessed. More than 80% of the dentists hold the opinion that such a centre is in the interest of both patients and dentists. The health education provided by the centre should, according to three quarters of the respondents, be directed to prevention and treatment; one quarter is in favor of health education directed to prevention only. The overall judgement on getting a second opinion is positive. Nevertheless, 22% judges asking for a second opinion as a sign of mistrust in one's own dentist. More than half of the dentists feel that a dental health education centre should be totally or partly financed by the Dutch Association of Dentists.