Elemental analysis of contemporary dental materials regarding potential beryllium content.

Exposure to beryllium (Be) can lead to lung pathologies, such as chronic beryllium disease (CBD). This occupational illness has been more prevalent among dental technicians compared to the non-exposed population. Although most manufacturers state that dental materials are Be-free, this prevalence raises the question of whether the materials are completely devoid of Be-traces. Thus, the objective of the present study was to analyze the elemental composition, with emphasis on Be, of a wide range of commercially available dental materials frequently used by dental laboratories. Samples of 32 different materials were collected and analyzed using inductively coupled plasma-optical emission spectrometry (ICP-OES) and X-ray fluorescence spectroscopy. The results showed that the Be content was below the limit of quantification in all included samples (< 0.00005 mass-%). Therefore, it can be concluded that possible traces of Be were below clinical relevance in dental materials. Exposure of dental technicians to alternative Be sources should be further evaluated.

Tailoring the composition of biocopolyester blends for dimensionally accurate extrusion-based printing, annealing and steam sterilization.

Fused filament fabrication (FFF) represents a straightforward additive manufacturing technique applied in the medical sector for personalized patient treatment. However, frequently processed biopolymers lack sufficient thermal stability to be used as auxiliary devices such as surgical guides. The aim of this study was to evaluate the dimensional accuracy of experimental biocopolyester blends with improved thermal characteristics after printing, annealing and sterilization. A total of 160 square specimens and 40 surgical guides for oral implant placement were printed. One subgroup of each material (n = 10) underwent thermal annealing before both subgroups were subjected to steam sterilization (134 °C; 5 min). Specimens were digitized and the deviation from the original file was calculated. The thermal behavior was analyzed using differential scanning calorimetry and thermogravimetric analysis. A one-way ANOVA and t-tests were applied for statistical analyses (p < 0.05). All biocopolyester blends showed warpage during steam sterilization. However, the material modification with mineral fillers (21-32 wt%) and nucleating agents in combination with thermal annealing showed a significantly reduced warpage of printed square specimens. Geometry of the printing object seemed to affect dimensional accuracy, as printed surgical guides showed less distortion between the groups. In summary, biocopolyesters did benefit from fillers and annealing to improve their dimensional stability.

Promotion of mental health in young adults via mobile phone app: study protocol of the ECoWeB (emotional competence for well-being in Young adults) cohort multiple randomised trials.

BACKGROUND: Promoting well-being and preventing poor mental health in young people is a major global priority. Building emotional competence (EC) skills via a mobile app may be an effective, scalable and acceptable way to do this. However, few large-scale controlled trials have examined the efficacy of mobile apps in promoting mental health in young people; none have tailored the app to individual profiles. METHOD/DESIGN: The Emotional Competence for Well-Being in Young Adults cohort multiple randomised controlled trial (cmRCT) involves a longitudinal prospective cohort to examine well-being, mental health and EC in 16-22 year olds across 12 months. Within the cohort, eligible participants are entered to either the PREVENT trial (if selected EC scores at baseline within worst-performing quartile) or to the PROMOTE trial (if selected EC scores not within worst-performing quartile). In both trials, participants are randomised (i) to continue with usual practice, repeated assessments and a self-monitoring app; (ii) to additionally receive generic cognitive-behavioural therapy self-help in app; (iii) to additionally receive personalised EC self-help in app. In total, 2142 participants aged 16 to 22 years, with no current or past history of major depression, bipolar disorder or psychosis will be recruited across UK, Germany, Spain, and Belgium. Assessments take place at baseline (pre-randomisation), 1, 3 and 12 months post-randomisation. Primary endpoint and outcome for PREVENT is level of depression symptoms on the Patient Health Questionnaire-9 at 3 months; primary endpoint and outcome for PROMOTE is emotional well-being assessed on the Warwick-Edinburgh Mental Wellbeing Scale at 3 months. Depressive symptoms, anxiety, well-being, health-related quality of life, functioning and cost-effectiveness are secondary outcomes. Compliance, adverse events and potentially mediating variables will be carefully monitored. CONCLUSIONS: The trial aims to provide a better understanding of the causal role of learning EC skills using interventions delivered via mobile phone apps with respect to promoting well-being and preventing poor mental health in young people. This knowledge will be used to develop and disseminate innovative evidence-based, feasible, and effective Mobile-health public health strategies for preventing poor mental health and promoting well-being. TRIAL REGISTRATION: ClinicalTrials.gov ( www.clinicaltrials.org ). Number of identification: NCT04148508 November 2019.

Predictive and concurrent validity of standardized neurodevelopmental examinations by the Griffiths scales and Bayley scales of infant development II.

Standardized examinations of preterm infants are used to identify candidates for early intervention. We aimed to assess the predictive power and concurrent validity of the mental development index of the Bayley scales of infant development II (Bayley MDI) and the Griffiths scales developmental quotient (Griffiths DQ) in healthy term and preterm infants <1500 g birth weight without major perinatal complications.137 Infants (89 term, 48 preterm) were examined by both tests at a corrected age of 6, 12, and 22 months, and 114 went on to undergo Bayley assessments at 39 months.There were significant correlations between Bayley and Griffiths results at 6, 12, and 22 months (r=0.530, 0.714, and 0.833, respectively, p<0.001) but Bland Altman plots revealed major systematic bias at 6 months (Griffiths>Bayley, mean differences 14.3±9.8) and 22 months (Bayley>Griffiths, mean difference 5.2±13.9) and wide 95% limits of agreement at 6, 12 and 22 months (35.9%, 40.0%, and 52.4%, respectively). The agreement for a presumptive diagnosis of developmental impairment in the group of preterm infants between Bayley examinations obtained at 39 months corrected age (reference) and previous examinations was poor at 6, 12, and 22 months for both Bayley and Griffiths (Cohen's kappa for Griffiths: 0.225, 0.192, 0.369; for Bayley: 0.121, 0.316, 0.369, respectively).Caution should be exercised when interpreting results from standardized neurodevelopmental examinations obtained during the first 2 years of life in comparatively well preterm infants.

Pantoprazole versus omeprazole: influence on meal-stimulated gastric acid secretion.

AIMS: To determine the influence of recommended therapeutic doses of pantoprazole and omeprazole on meal-stimulated acid secretion. METHODS: In this double-blind, placebo-controlled, three-period crossover study, 12 healthy male volunteers received 40 mg pantoprazole od, 20 mg omeprazole od or placebo at 08:00 h for 5 days in a randomized order. Meal-stimulated acid secretion was determined by means of a homogenized test meal, and intragastric titration on day 1, 4-6 h, 8-10 h, 16-18 h, and 24-26 h, and on days 3 and 5, 4-6 h after oral drug administration. RESULTS: On day 1 (4-6 h after oral drug administration), meal-stimulated acid secretion was decreased by 36% and 24% after administration of 40 mg pantoprazole or 20 mg omeprazole, respectively. After 3 and 5 days of dosing, the decreases were 88% and 85% with 40 mg pantoprazole, and 70% and 74% with 20 mg omeprazole. At all measuring points during the 5-day dosing periods, 40 mg pantoprazole proved superior to 20 mg omeprazole in inhibiting meal-stimulated gastric acid secretion. The differences were statistically significant for pantoprazole on day 1, 24-26 h after oral drug administration and on day 3 (P = 0.0425 and P = 0.0244, respectively). On day 1, only pantoprazole was significantly better than placebo (P = 0.0210, 4-6 h after dosing; P = 0.0093, 8-10 h after dosing and P = 0.0068, 16-18 h after dosing). CONCLUSION: Pantoprazole 40 mg is significantly more effective than omeprazole 20 mg in inhibiting meal-stimulated acid secretion. In addition, pantoprazole exhibits a more rapid onset of action.

Enteric coating of aspirin significantly decreases gastroduodenal mucosal lesions.

BACKGROUND: Low-dose aspirin (acetylsalicylic acid, ASA) increases the risk of developing peptic ulceration. AIM: To investigate the gastroduodenal mucosal tolerability of enteric-coated ASA (EC-ASA) 100 mg/day compared to either placebo (study 1) or plain ASA 100 mg/day (study 2) in healthy volunteers. METHODS: Study 1: In this double-blind study 18 volunteers received randomized dosing with either EC-ASA 100 mg or placebo for 15 days. Study 2: 41 volunteers underwent randomized 7-day dosing of either EC-ASA 100 mg or plain ASA 100 mg in this double-blind, parallel-group, comparison study. In both studies acute gastroduodenal mucosal lesions were assessed endoscopically before treatment, on the morning of day 1 after the first dose (only in study 2), and on the morning after the last dose of the test medication. RESULTS: Study 1 did not reveal any significant differences between the lesion scores of EC-ASA and placebo. In contrast, in study 2 significantly higher total gastroduodenal mucosal lesion scores were observed on day 1 after the first dose and after 7 days of dosing with plain ASA (mean sum of the lesion scores in the gastric fundus, body, antrum and in the duodenal bulb: day 1: plain ASA 3.95+/-3.38 vs. EC-ASA 1.43+/-1.91, P = 0.03; day 7: plain ASA 6.35+/-4.10 vs. EC-ASA 2.00+/-2.02, P = 0.0004). Tolerance of the test drugs was good, and no other adverse events were observed. CONCLUSIONS: Enteric-coated aspirin 100 mg/day causes significantly less gastroduodenal damage over 7 days than the same dose of plain aspirin, when given to healthy subjects. There was little gastric injury and no significant differences between EC-ASA and placebo in this respect.

The effects of oral rabeprazole on endocrine and gastric secretory function in healthy volunteers.

AIM: To evaluate the short-term effects of rabeprazole 20 mg on endocrine parameters, in particular serum testosterone and cortisol, and on 24 h intragastric pH, H+ activity and nocturnal gastric acid secretion. METHODS: In this double-blind, two-period crossover study, 12 healthy young male volunteers were randomly given oral rabeprazole 20 mg o.m. or placebo for 14 days. There was a washout period of at least 1 week between the two studies. The effects of rabeprazole and placebo on cortisol and testosterone (primary criteria), and on tri-iodothyronine, thyroxine, 17beta-oestradiol, thyroid-stimulating hormone, thyroxine-binding protein, parathyroid hormone, insulin, glucagon, rennin, aldosterone, follicle-stimulating hormone, luteotrophic hormone, prolactin, somatotrophic hormone, dehydroepiandrosterone, cortisol-binding globulin and urinary 6-beta hydroxycortisol were compared. Intragastric 24 h pH, 24 h H+ activity and nocturnal gastric acid secretion were determined by pH probe and gastric aspiration. RESULTS: Rabeprazole produced no clinically relevant effects on endocrine function as assessed by measurement of serum testosterone, circadian serum cortisol levels, ACTH-stimulated serum cortisol levels and 17 other endocrine function tests. Rabeprazole significantly increased the 24 h median pH values compared to placebo (on Days 7 and 14 median values ranged from 3.92 to 6.88 with rabeprazole and from 1.48 and 4.22 with placebo, P < 0.001) and significantly decreased the integrated 24 h H+ activity (AUC08--08) from 343 mmol/L/h with placebo to 44 mmol/L/h with rabeprazole (P < 0.001). Following cessation of dosing, intragastric pH levels decreased and H+ activity increased, but acid secretion did not recover completely during the next 72 h. The mean value for nocturnal gastric acid secretion on Days 7 and 8 was 36 mmol/6 h with placebo and 5.6 mmol/6 h with rabeprazole (P < 0.001). Rabeprazole was well tolerated. CONCLUSION: Rabeprazole did not influence endocrine function in healthy young male volunteers during short-term dosing. Rabeprazole substantially increased intragastric pH over a 24 h period and significantly decreased intragastric acidity and nocturnal gastric acid secretion.

Lansoprazole versus omeprazole: influence on meal-stimulated gastric acid secretion.

AIMS: To investigate, by means of meal-stimulated acid secretion, the extent to which differences in plasma half-life, bioavailability and the recommended therapeutic dose can influence the antisecretory potency of lansoprazole and omeprazole. METHODS: In this double-blind, placebo-controlled, crossover study, 10 healthy male volunteers received 15 mg or 30 mg lansoprazole, 20 mg or 40 mg omeprazole or placebo for 5 days, in a randomized order. Meal-stimulated acid secretion was determined by means of a homogenized test meal and intragastric titration. RESULTS: On day 1, meal-stimulated acid secretion was decreased by 35% and 45% after administration of 15 mg or 30 mg lansoprazole, and by 16% and 42% after 20 mg or 40 mg omeprazole. After 3 and 5 days of dosing the decreases were 53% and 48% with 15 mg lansoprazole, 82% and 82% with 30 mg lansoprazole, 43% and 39% with 20 mg omeprazole, and 76% and 83% with 40 mg omeprazole. At all measuring points during the 5-day dosing periods, lansoprazole 15 mg and 30 mg proved superior to 20 mg omeprazole in inhibiting meal-stimulated gastric acid secretion, but the differences were only statistically significant for the lansoprazole 30 mg dose, 30 mg lansoprazole and 40 mg omeprazole proved equipotent. On day 1 only 30 mg lansoprazole was significantly better than placebo. CONCLUSION: This study demonstrated the following order of antisecretory potency: 30 mg lansoprazole = 40 mg omeprazole > 15 mg lansoprazole approximately 20 mg omeprazole.

[Effective prevention of indomethacin-induced gastroduodenal mucosal lesions with roxatidine acetate]. / Wirksame Prophylaxe der durch Indometacin induzierten gastroduodenalen Schleimhautläsionen mit Roxatidinacetat.

In this randomized single-blind cross-over study the gastroduodenal damaging effect of indometacin 75 mg bid alone and in combination with roxatidine acetate (CAS 78628-28-1, Roxit) 75 mg nocte or 75 mg bid was evaluated in 12 healthy male volunteers. Prior to the start of the three therapeutic periods subjects underwent endoscopic examination to exclude gastroduodenal mucosa lesions. On days 7 and 14 of therapy 2 h after the application of the last indometacin dose subjects underwent endoscopy again. The 7- and 14-days administration of indometacin 75 mg bid, indometacin 75 mg bid plus roxatidine 75 mg nocte and indometacin 75 mg bid plus roxatidine 75 mg bid led to gastroduodenal mucosa lesion scores of 1.67 +/- 0.40 and 2.00 +/- 0.35, 1.33 +/- 0.28 and 1.50 +/- 0.29, 0.42 +/- 0.23 and 1.00 +/- 0.33 (mean +/- SEM), respectively. These differences were statistically significant when comparing indometacin 75 mg bid versus indometacin 75 mg bid plus roxatidine 75 mg bid (p < 0.004 and < 0.008, respectively). This study shows that roxatidine acetate represents an effective alternative in the prophylaxis of NSAID-induced gastroduodenal mucosa lesions.

Semisynthetic chemical modification of the antifungal lipopeptide echinocandin B (ECB): structure-activity studies of the lipophilic and geometric parameters of polyarylated acyl analogs of ECB.

Echinocandin B (ECB) is a lipopeptide composed of a complex cyclic peptide acylated at the N-terminus by linoleic acid. Enzymatic deacylation of ECB provided the peptide "nucleus" as a biologically inactive substrate from which novel ECB analogs were generated by chemical reacylation at the N-terminus. Varying the acyl group revealed that the structure and physical properties of the side chain, particularly its geometry and lipophilicity, played a pivotal role in determining the antifungal potency properties of the analog. Using CLOGP values to describe and compare the lipophilicities of the side chain fragments, it was shown that values of > 3.5 were required for expression of antifungal activity. Secondly, a linearly rigid geometry of the side chain was the most effective shape in enhancing the antifungal potency. Using these parameters as a guide, a variety of novel ECB analogs were synthesized which included arylacyl groups that incorporated biphenyl, terphenyl, tetraphenyl, and arylethynyl groups. Generally the glucan synthase inhibition by these analogs correlated well with in vitro and in vivo activities and was likewise influenced by the structure of the side chain. These structural variations resulted in enhancement of antifungal activity in both in vitro and in vivo assays. Some of these analogs, including LY303366 (14a), were effective by the oral route of administration.

Effects of pantoprazole on endocrine function in healthy male volunteers.

METHOD: In a randomized, double-blind, two-period crossover study, pantoprazole 40 mg or placebo were given orally to 12 male volunteers for 2 weeks each. There was a wash-out period of at least 1 week between the two treatment periods. The effects of pantoprazole or placebo on cortisol and testosterone (primary criteria), and tri-iodothyronine, thyroxine, thyroid-stimulating hormone, thyronine-binding protein, parathyroid hormone, insulin, glucagon, renin, aldosterone, follicle-stimulating hormone, luteotrophic hormone, prolactin and somatotrophic hormone were compared. In addition, intragastric 24-h pH, 24-h H(+)-activity, and volume of nocturnal gastric juice were determined by gastric aspiration technique. RESULTS: Pantoprazole did not influence plasma levels of testosterone, circadian cortisol concentrations or plasma cortisol levels after exogenous adrenocorticotropic hormone stimulation, as compared to placebo (P > 0.05, Koch's test). Furthermore, there were no clinically relevant changes with any of the other endocrine parameters. Pantoprazole significantly increased the median 24-h pH (group median 4.3 vs. 1.8; P < 0.001) and decreased 24-h H(+)-activity (4.0 vs. 22.6 mmol/L; P < 0.001). The volume of nocturnal gastric juice did not significantly differ between the two treatments. Pantoprazole was well tolerated and the frequency of adverse events was similar to placebo. No drug-related changes in laboratory values were observed. CONCLUSION: Pantoprazole did not influence endocrine function in healthy male volunteers during short-term treatment.

Ontogenesis of monoamine oxidase-A and -B in the human brain frontal cortex.

The effect of several antemortem and postmortem factors (patients' age, sex, postmortem delay, storage time, laterality and brain weight) on both monoamine oxidase-A (MAO-A) and -B (MAO-B) activity was investigated in the frontal cortex of human brains. The MAO-A activity decreases rapidly during the first two years of life and remains constant thereafter. In contrast, the MAO-B activity keeps unchanged during early childhood and raises during advanced age. These findings seem to be consistent with a genetic regulation and a variation in cell type assembling during brain development and aging.

Cleavage of synthetic peptides by purified poliovirus 3C proteinase.

Synthetic peptides, 14-16 residues in length, were used as substrates for purified recombinant poliovirus proteinase 3C. The sequences of the substrates correspond to the sequences of authentic cleavage sites in the poliovirus polyprotein, all of which contain Gln-Gly at the scissile bond. Specificity of cleavages was demonstrated by analysis of 3C digests of synthetic peptides. Relative rate constants for the cleavages were derived by competition experiments. The rate constants roughly correlated with the estimated half-life of the homologous precursor proteins detected in poliovirus-infected cells. The peptide most resistant to cleavage corresponded to the 3C/3D junction, a site known to be cleaved very slowly by 3C in vivo. Substitution of threonine for alanine in P4 position of this peptide, however, resulted in significant cleavage. This observation supports the hypothesis that the residue in P4 position, in addition to the Gln-Gly in P1 and P1', respectively, contributes to substrate recognition. Ac-Gln-Gly-NH2 was not a substrate for 3C.

Regional distribution of [3H]MK-801 binding sites in the human brain.

Specific [3H]MK-801 binding was measured under equilibrium conditions in 8 brain regions (frontal cortex, area entorhinalis, hippocampus, amygdala, putamen, thalamus, substantia nigra and nucleus dentatus) in the right hemisphere of the human brain (n = 4). In addition, binding was assessed in 3 of these regions (frontal cortex, area entorhinalis and putamen) in the left hemisphere. High [3H]MK-801 binding levels occurred in the area entorhinalis, frontal cortex, hippocampus and amygdala, medium levels were observed in the putamen and thalamus and low levels were found in the substantia nigra and nucleus dentatus. No evidence for laterality of [3H]MK-801 binding sites was observed in the 3 regions which were investigated on both sides of the brain.

[3H]MK-801 binding sites in post-mortem human frontal cortex.

The binding of [3H]MK-801 ((+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate) was investigated in extensively washed homogenates of post-mortem human frontal cortex. The association of [3H]MK-801 proceeded slowly (t1/2 = 553 min) and reached equilibrium only after a prolonged incubation (greater than 24 h). The dissociation of [3H]MK-801 from the binding site was also slow (t1/2 = 244 min). Glutamate, glycine and magnesium markedly increased the rate of association (t1/2 = 14.8 min) and dissociation (t1/2 = 36.5 min). At equilibrium, the binding was not altered by these substances. Specific binding was linear with protein concentration, was saturable, reversible, stereoselective, heat-labile and was nearly absent in the white matter. Scatchard analysis of the saturation curves obtained at equilibrium indicated that there was a high-affinity (Kd1 1.39 +/- 0.21 nM, Bmax1 0.483 +/- 0.084 pmol/mg protein) and a low-affinity (Kd2 116.25 +/- 50.79 nM, Bmax2 3.251 +/- 0.991 pmol/mg protein) binding site. All competition curves obtained with (+)-MK-801, (-)-MK-801, phencyclidine and ketamine had Hill coefficients of less than unity and were best explained by a two-site model. Thus, our results demonstrate the presence of binding sites for MK-801 in post-mortem human brains and provide evidence for binding site heterogeneity. Furthermore, glutamate, glycine and magnesium accelerate the association and dissociation of [3H]MK-801 to and from its binding sites. The results add support to the hypothesis that MK-801, glutamate, glycine and magnesium all bind to different sites on the NMDA receptor-ion channel complex.

[3H]MK-801 binding sites in postmortem brain regions of schizophrenic patients.

[3H]MK-801 binding was used as a marker for the NMDA receptorion channel complex in postmortem brain samples from the frontal cortex, hippocampus, putamen, entorhinal region, and amygdala of schizophrenic patients and controls. In schizophrenia [3H]MK-801 binding levels were increased in all brain regions investigated reaching significance in the putamen.

Effect of antemortem and postmortem factors on [3H]MK-801 binding in the human brain: transient elevation during early childhood.

The effect of a number of antemortem and postmortem factors on [3H]MK-801 binding was investigated under equilibrium conditions in the frontal cortex of human brains of 38 controls. Binding values transiently increased during the early postnatal period reaching a maximum at the age of about 2 years. After age 10 years [3H]MK-801 binding sites disappeared at 5.7% per decade. The storage time of brain tissue had a reducing effect on these binding sites. There was no effect of gender, brain weight or postmortem time interval and the binding sites were bilaterally symmetrically distributed in the frontal cortex.

Calcitonin gene-related peptides I and II and calcitonin: distinct effects on gastric acid secretion in humans.

The human calcitonin gene-related peptides I and II (CGRP I and CGRP II) are two neuropeptides that have been recognized throughout the gastrointestinal system including the stomach. The present study was undertaken to compare in healthy volunteers the effects of intravenous infusions of CGRP I and CGRP II (79 pmol/kg.h) on pentagastrin-stimulated acid secretion to those of calcitonin (88 pmol/kg.h). Calcitonin gene-related peptide I did not inhibit basal or pentagastrin-stimulated acid secretion. However, CGRP II and calcitonin inhibited pentagastrin-stimulated acid responses by 20% and 28%, respectively (p less than 0.05 and p less than 0.01), whereas basal acid output was only reduced with calcitonin (p less than 0.05). These effects were recognized with low doses of pentagastrin, and absent with high doses suggesting competitive inhibition. Furthermore, step-doses of CGRP I and CGRP II (79-320 pmol/kg.h) were given intravenously on continuous pentagastrin stimulation and compared with calcitonin (88-352 pmol/kg.h). Calcitonin gene-related peptide II and calcitonin induced a dose-dependent decrease of acid output, whereas CGRP I was ineffective. The inhibitory effects of CGRP II and calcitonin are not due to increased gastric alkaline secretion or to somatostatin release, as neither peptide stimulated gastric bicarbonate secretion or induced an increase in circulating somatostatin. In conclusion, CGRP II, unlike CGRP I, inhibits gastric acid secretion in humans. Inhibitory effects of CGRP II and of calcitonin were comparable. The results imply that CGRP I and II, at the level of the stomach, have distinct biological properties in humans.

Pharmacokinetics of ofloxacin in patients on haemodialysis treatment.

Serum concentrations and pharmacokinetic parameters of ofloxacin were measured in 10 patients on haemodialysis treatment. Serum half-life during the interdialytic interval was 48 hours, and during haemodialysis treatment 10 hours. The decrease in serum concentrations during a 4-hour haemodialysis was 25%. After several doses of ofloxacin, saturation of the tissues and a rediffusion of ofloxacin from the tissues during haemodialysis has to be assumed. This equalizes the rate of elimination, and the serum ofloxacin concentration did not change during the last 2 hours of haemodialysis. The negative influence of phosphate binders on the resorption of ofloxacin can be confirmed. The following ofloxacin dosage regimen is recommended in haemodialysis patients: 200 mg initially, 100 mg loading dose after the first haemodialysis, then 100 mg daily.