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1.
Neth Heart J ; 30(1): 47-57, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34259995

ABSTRACT

Cardiovascular disease (CVD) is a major cause of morbidity and mortality worldwide. For many years guidelines have listed optimal preventive therapy. More recently, novel therapeutic options have broadened the options for state-of-the-art CV risk management (CVRM). In the majority of patients with CVD, risk lowering can be achieved by utilising standard preventive medication combined with lifestyle modifications. In a minority of patients, add-on therapies should be considered to further reduce the large residual CV risk. However, the choice of which drug combination to prescribe and in which patients has become increasingly complicated, and is dependent on both the absolute CV risk and the reason for the high risk. In this review, we discuss therapeutic decisions in CVRM, focusing on (1) the absolute CV risk of the patient and (2) the pros and cons of novel treatment options.

2.
Adv Health Sci Educ Theory Pract ; 26(2): 683-711, 2021 05.
Article in English | MEDLINE | ID: mdl-33128662

ABSTRACT

Gamification refers to using game attributes in a non-gaming context. Health professions educators increasingly turn to gamification to optimize students' learning outcomes. However, little is known about the concept of gamification and its possible working mechanisms. This review focused on empirical evidence for the effectiveness of gamification approaches and theoretical rationales for applying the chosen game attributes. We systematically searched multiple databases, and included all empirical studies evaluating the use of game attributes in health professions education. Of 5044 articles initially identified, 44 met the inclusion criteria. Negative outcomes for using gamification were not reported. Almost all studies included assessment attributes (n = 40), mostly in combination with conflict/challenge attributes (n = 27). Eight studies revealed that this specific combination had increased the use of the learning material, sometimes leading to improved learning outcomes. A relatively small number of studies was performed to explain mechanisms underlying the use of game attributes (n = 7). Our findings suggest that it is possible to improve learning outcomes in health professions education by using gamification, especially when employing game attributes that improve learning behaviours and attitudes towards learning. However, most studies lacked well-defined control groups and did not apply and/or report theory to understand underlying processes. Future research should clarify mechanisms underlying gamified educational interventions and explore theories that could explain the effects of these interventions on learning outcomes, using well-defined control groups, in a longitudinal way. In doing so, we can build on existing theories and gain a practical and comprehensive understanding of how to select the right game elements for the right educational context and the right type of student.


Subject(s)
Health Occupations , Learning , Humans , Students
3.
Neth Heart J ; 29(12): 654-661, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34495448

ABSTRACT

OBJECTIVES: The aim of this study is to evaluate device size selection in patients within the borderline annulus size range undergoing transcatheter aortic valve replacement (TAVR) and to assess if pre-procedural patient-specific computer simulation will lead to the selection of a different device size than standard of care. BACKGROUND: In TAVR, appropriate device sizing is imperative. In borderline annulus size cases no standardised technique for tailored device size selection is currently available. Pre-procedural patient-specific computer simulation can be used, predicting the risk for paravalvular leakage (PVL) and need for permanent pacemaker implantation (PPI). METHODS: In this multicentre retrospective study, 140 patients in the borderline annulus size range were included. Hereafter, device size selection was left to the discretion of the operator. After TAVR, in 24 of the 140 patients, patient-specific computer simulation calculated the most appropriate device size expected to give the lowest risk for PVL and need for PPI. In these 24 patients, device size selection based on patient-specific computer simulation was compared with standard-of-care device size selection relying on a standardised matrix (Medtronic). RESULTS: In a significant proportion of the 140 patients (26.4%) a different device size than recommended by the matrix was implanted. In 10 of the 24 patients (41.7%) in whom a computer simulation was performed, a different device size was recommended than by means of the matrix. CONCLUSIONS: Device size selection in patients within the borderline annulus size range is still ambiguous. In these patients, patient-specific computer simulation is feasible and can contribute to a more tailored device size selection.

4.
Neth Heart J ; 29(12): 632-642, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34724147

ABSTRACT

INTRODUCTION: Despite considerable advances in the last decade, major adverse events remain a concern after transcatheter aortic valve implantation (TAVI). The aim of this study was to provide a detailed overview of their underlying causes and contributing factors in order to identify key domains for quality improvement. METHODS: This observational, prospective registry included all patients undergoing TAVI between 31 December 2015 and 1 January 2020 at the St. Antonius Hospital in Nieuwegein and the University Medical Centre in Utrecht. Outcomes of interest were all-cause mortality, stroke, major bleeding, life-threatening or disabling bleeding, major vascular complications, myocardial infarction, severe acute kidney injury and conduction disturbances requiring permanent pacemaker implantation within 30 days after TAVI, according to the Valve Academic Research Consortium­2 criteria. RESULTS: Of the 1250 patients who underwent TAVI in the evaluated period, 146 (11.7%) developed a major complication. In 54 (4.3%) patients a thromboembolic event occurred, leading to stroke in 36 (2.9%), myocardial infarction in 13 (1.0%) and lower limb ischaemia in 11 (0.9%). Major bleeding occurred in 65 (5.2%) patients, most frequently consisting of acute cardiac tamponade (n = 25; 2.0%) and major access-site bleeding (n = 21; 1.7%). Most complications occurred within 1 day of the procedure. Within 30 days a total of 54 (4.3%) patients died, the cause being directly TAVI-related in 30 (2.4%). Of the patients who died from causes that were not directly TAVI-related, 14 (1.1%) had multiple hospital-acquired complications. CONCLUSION: A variety of underlying mechanisms and causes form a wide spectrum of major threats affecting early safety in 11.7% of patients undergoing TAVI in a contemporary cohort of real-world patients.

5.
Neth Heart J ; 28(10): 520-525, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32333256

ABSTRACT

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is increasingly being used as an alternative to conventional surgical valve replacement. Prosthetic valve endocarditis (PVE) is a rare but feared complication after TAVR, with reported first-year incidences varying from 0.57 to 3.1%. This study was performed to gain insight into the incidence and outcome of PVE after TAVR in the Netherlands. METHODS: A multicentre retrospective registry study was performed. All patients who underwent TAVR in the period 2010-2017 were screened for the diagnosis of infective endocarditis in the insurance database and checked for the presence of PVE before analysis of general characteristics, PVE parameters and outcome. RESULTS: A total of 3968 patients who underwent TAVR were screened for PVE. During a median follow-up of 33.5 months (interquartile range (IQR) 22.8-45.8), 16 patients suffered from PVE (0.4%), with a median time to onset of 177 days (IQR 67.8-721.3). First-year incidence was 0.24%, and the overall incidence rate was 0.14 events per 1000 person-years. Overall mortality during follow-up in our study was 31%, of which 25% occurred in hospital. All patients were treated conservatively with intravenous antibiotics alone, and none underwent a re-intervention. Other complications of PVE occurred in 5 patients (31%) and included aortic abscess (2), decompensated heart failure (2) and cerebral embolisation (1). CONCLUSION: PVE in patients receiving TAVR is a relatively rare complication and has a high mortality rate.

6.
Neth Heart J ; 27(5): 263-271, 2019 May.
Article in English | MEDLINE | ID: mdl-30989470

ABSTRACT

BACKGROUND: Sex differences in acute coronary syndrome (ACS) have been reported, but little is known about the situation in the Netherlands. METHODS: This registry is a merge of available data on ACS patients in the electronic data capture systems of 11 centres with 24/7 interventional cardiology services. We included patients >18 years undergoing a cardiac catheterisation between 2010-2012. We evaluated sex differences in clinical and procedural characteristics and 1­year mortality. RESULTS: A total of 29,265 ACS patients (8,720 women and 20,545 men) were registered. Women were on average 4.5 years older (68.5 vs 63.0 years, p < 0.001) and had a higher prevalence of hypertension (62.7 vs 49.8%, p < 0.001) and insulin-dependent diabetes mellitus (9.6 vs 6.8%, p < 0.001) than men. Women less often presented with ST-elevation myocardial infarction (43.7% vs 47.6%, p < 0.001) and appeared to have less extensive coronary artery disease than men. Women less often underwent coronary angiography by radial access (52.5 vs 55.9%, p < 0.001). One-year mortality was higher in women than in men (7.3% and 5.6%, p < 0.001). More specific, the relationship between sex and mortality was age-dependent and showed higher mortality in women ≤71 years, but lower mortality in older women compared with men (p-interaction <0.001). CONCLUSION: We found differences in clinical and procedural characteristics and outcome between women and men admitted for ACS, which are in line with other Western countries. The limitations of our registry, based on existing local databases, can be overcome by the use of the prospective Netherlands Heart Registry that is currently in development.

7.
Genes Immun ; 16(4): 247-52, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25611558

ABSTRACT

The classical human leukocyte antigen (HLA)-DRB1*03:01 and HLA-DRB1*04:01 alleles are established autoimmune hepatitis (AIH) risk alleles. To study the immune-modifying effect of these alleles, we imputed the genotypes from genome-wide association data in 649 Dutch AIH type-1 patients. We therefore compared the international AIH group (IAIHG) diagnostic scores as well as the underlying clinical characteristics between patients positive and negative for these HLA alleles. Seventy-five percent of the AIH patients were HLA-DRB1*03:01/HLA-DRB1*04:01 positive. HLA-DRB1*03:01/HLA-DRB1*04:01-positive patients had a higher median IAIHG score than HLA-DRB1*03:01/HLA-DRB1*04:01-negative patients (P<0.001). We did not observe associations between HLA alleles and alanine transaminase levels (HLA-DRB1*03:01: P=0.2; HLA-DRB1*04:01; P=0.5); however, HLA-DRB1*03:01 was independently associated with higher immunoglobulin G levels (P=0.04). The HLA-DRB1*04:01 allele was independently associated with presentation at older age (P=0.03) and a female predominance (P=0.04). HLA-DRB1*03:01-positive patients received immunosuppressive medication and liver transplantation. In conclusion, the HLA-DRB1*03:01 and HLA-DRB1*04:01 alleles are both independently associated with the aggregate diagnostic IAIHG score in type-1 AIH patients, but are not essential for AIH development. HLA-DRB1*03:01 is the strongest genetic modifier of disease severity in AIH.


Subject(s)
HLA-DRB1 Chains/genetics , Hepatitis, Autoimmune/genetics , Adult , Age of Onset , Aged , Cohort Studies , Female , Genetic Predisposition to Disease , HLA-DRB1 Chains/immunology , Hepatitis, Autoimmune/diagnosis , Hepatitis, Autoimmune/etiology , Hepatitis, Autoimmune/therapy , Humans , Immunoglobulin G/blood , Liver Transplantation , Male , Middle Aged , Multivariate Analysis , Treatment Outcome
8.
Neth Heart J ; 22(4): 167-73, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24522952

ABSTRACT

AIMS: Everolimus-eluting stents (EES) were superior to sirolimus-eluting stents (SES) in a dedicated myocardial infarction trial, a finding that was not observed in trials with low percentages of ST-elevation myocardial infarction (STEMI). Therefore, this study sought to investigate the influence of clinical presentation on outcome after EES and SES implantation. METHODS: A pooled population of 1602 randomised patients was formed from XAMI (acute MI trial) and APPENDIX-AMI (all-comer trial). Primary outcome was cardiac mortality, MI and target vessel revascularisation at 2 years. Secondary endpoints included definite/probable stent thrombosis (ST). Adjustment was done using Cox regression. RESULTS: In total, 902 EES and 700 SES patients were included, of which 44 % STEMI patients (EES 455; SES 257) and 56 % without STEMI (EES 447; SES 443). In the pooled population, EES and SES showed similar outcomes during follow-up. Moreover, no differences in the endpoints were observed after stratification according to presentation. Although a trend toward reduced early definite/probable ST was observed in EES compared with SES in STEMI patients, long-term ST rates were low and comparable. CONCLUSIONS: EES and SES showed a similar outcome during 2-year follow-up, regardless of clinical presentation. Long-term safety was excellent for both devices, despite wide inclusion criteria and a large sub-population of STEMI patients.

9.
Endoscopy ; 44(5): 462-72, 2012 May.
Article in English | MEDLINE | ID: mdl-22389231

ABSTRACT

INTRODUCTION: The Global Rating Scale (GRS) is a quality assurance program that was developed in England to assess patient-centered care in endoscopy. The aim of the current study was to evaluate patient experiences of colonoscopy using the GRS in order to compare different departments and to provide benchmarks. The study also evaluated factors associated with patient satisfaction. METHODS: A GRS questionnaire was used both before and after the procedure in outpatients undergoing colonoscopy. The questionnaire assessed the processes associated with the colonoscopy, from making the appointment up until discharge. Mean values and ranges of 12 endoscopy departments were calculated together with P values in order to assess heterogeneity. RESULTS: In total, 1904 pre-procedure and 1532 (80 %) post-procedure questionnaires were returned from 12 endoscopy departments. The mean time patients had to wait for their procedure was 4.3 weeks (range 3.1 - 5.8 weeks), and 54 % (range 35 - 64 %; P < 0.001) reported being given a choice of appointment dates/times. Discomfort during colonoscopy was reported by 20 % (range 8 - 40 %; P < 0.001). Recovery room privacy was satisfactory for 76 % of patients (range 66 - 90 %; P < 0.05). The majority of patients reported being sufficiently informed about what to do in case of problems after discharge (79 %, range 43 - 98 %; P < 0.001), and 85 % of individuals stated that they would be willing to repeat the colonoscopy procedure (range 72 - 92 %; P < 0.001). Factors associated with a decreased willingness to return were the burdensome bowel preparation (odds ratio [OR] = 0.25; P < 0.001), "rushing staff" attitude (OR = 0.57; P < 0.05), low acceptance of the procedure (OR = 0.42; P < 0.01), and more discomfort than expected (OR = 0.54; P < 0.05). CONCLUSION: Overall patient experiences with colonoscopy were satisfactory, but they also showed considerable variation. This study shows that use of a GRS patient questionnaire is feasible in the Dutch endoscopy setting for the assessment of patient experience. The significant variability between endoscopy units can be used to benchmark services and enable shortcomings to be identified.


Subject(s)
Benchmarking , Colonoscopy , Outcome and Process Assessment, Health Care , Patient Satisfaction , Female , Hospital Departments , Humans , Male , Middle Aged , Netherlands , Patient-Centered Care , Quality Assurance, Health Care , Surveys and Questionnaires
10.
BJOG ; 119(4): 422-30, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22324918

ABSTRACT

OBJECTIVE: To assess the absolute risk of fetal loss associated with hereditary deficiencies of antithrombin (AT), protein C (PC) and protein S (PS), and the contribution of additional thrombophilic defects to this risk. DESIGN: A retrospective family cohort study. SETTING: A tertiary referral teaching hospital. POPULATION: Women from families with hereditary deficiencies of AT, PC and PS, and their non-deficient relatives. METHODS: We assessed the absolute risk of fetal loss, comparing deficient women with non-deficient female relatives. MAIN OUTCOME MEASURES: Early, late and total fetal loss rates; odds ratios of fetal loss. RESULTS: We evaluated 289 women, who had 860 pregnancies. The total fetal loss rates were 23% (AT deficient), 26% (PC deficient), 11% (type-I PS deficient) and 15% (type-III PS deficient), compared with 11, 18, 12 and 13% in non-deficient women, respectively. Odds ratios were 2.3 (95% CI 0.9-6.1), 2.1 (95% CI 0.9-4.7), 0.7 (95% CI 0.2-1.8) and 1.1 (95% CI 0.6-2.0), none of which reached statistical significance. Differences were mainly the result of higher late fetal loss rates in women deficient in AT (OR 11.3, 95% CI 3.0-42.0) and PC (OR 4.7, 95% CI 1.3-17.4). The concomitance of factor-V Leiden and prothrombin G20210A was observed in 19% of women, and did not increase the risk of fetal loss. CONCLUSIONS: Although absolute risks of fetal loss were high, odds ratios of total fetal loss were not statistically significant in deficient versus non-deficient women. However the higher absolute risks appeared to reflect higher late fetal loss rates as opposed to early fetal loss rates. An additional effect of concomitance of factor-V Leiden and prothrombin G20210A was not demonstrated, which may result from the exclusion of women at highest risk of venous thromboembolism, or from the small numbers sampled in the study.


Subject(s)
Abortion, Spontaneous/genetics , Factor V/genetics , Mutation , Prothrombin/genetics , Thrombophilia/genetics , Adult , Cohort Studies , Female , Genetic Testing , Hospitals, University , Humans , Nuclear Family , Odds Ratio , Point Mutation , Pregnancy , Retrospective Studies , Risk Assessment , Risk Factors , Venous Thrombosis/genetics
12.
Am J Med Genet B Neuropsychiatr Genet ; 150B(6): 782-98, 2009 Sep 05.
Article in English | MEDLINE | ID: mdl-19105204

ABSTRACT

The CGG-repeat present in the 5'UTR of the FMR1 gene is unstable upon transmission to the next generation. The repeat is up to 55 CGGs long in the normal population. In fragile X patients, a repeat length exceeding 200 CGGs (full mutation: FM) generally leads to methylation of the repeat and the promoter region, which is accompanied by silencing of the FMR1 gene. The gene product FMRP is involved in regulation of transport and translation of certain mRNA in the dendrite, thereby affecting synaptic plasticity. This is central to learning and memory processes. The absence of FMRP seen in FM is the cause of the mental retardation seen in fragile X patients. The premutation (PM) is defined as 55-200 CGGs. Female PM carriers are at risk of developing primary ovarian insufficiency. Recently it was discovered that elderly PM carriers might develop a progressive neurodegenerative disorder called fragile X-associated tremor/ataxia syndrome. Although arising from the mutations in the same gene, distinct mechanisms lead to fragile X syndrome (absence of FMRP) and FXTAS (toxic RNA gain of function). The pathogenic mechanisms thought to underlie these disorders are discussed, with a specific emphasis on FXTAS. This review gives insight on the implications of all possible repeat length categories seen in fragile X families.


Subject(s)
Ataxia/genetics , Fragile X Mental Retardation Protein/genetics , Fragile X Syndrome/genetics , Tremor/genetics , Trinucleotide Repeats/genetics , Animals , Ataxia/complications , Disease Models, Animal , Female , Fragile X Mental Retardation Protein/metabolism , Fragile X Syndrome/complications , Fragile X Syndrome/physiopathology , Humans , Male , Mice , Syndrome , Tremor/complications
13.
Sci Rep ; 9(1): 2140, 2019 02 14.
Article in English | MEDLINE | ID: mdl-30765828

ABSTRACT

The process of macroinvertebrate drift in freshwater lowland streams is characterized by dislodgement, drift distance and subsequent return to the bottom. Refuges are important to all drift phases, since they may help larvae to avoid dislodgement and to escape from drift, even more so if the refuge structure is complex and heterogeneous. The aim of the present study was therefore to determine the influence of refuge heterogeneity on the ability of caddisfly larvae to return to the bottom from drift and to avoid secondary dislodgement. To this purpose a series of indoor flume experiments were undertaken, testing six Limnephilidae (Trichoptera) species, that occur on a gradient from lotic to lentic environments. Bed morphology (plain, refuges with or without leaf patches) and flow velocity (low (0.1 m/s), intermediate (0.3 m/s) and high (0.5 m/s) were manipulated. We showed that all species were favoured by refuges and that especially for species on the lentic end of the gradient (L. lunatus, L. rhombicus and A. nervosa), the ability to escape from drift and to avoid secondary dislodgement was increased. Moreover, we showed that all species spent more time in refuges than in open channel parts and more time in heterogeneous refuges (leaf patches) than in bare refuges, the latter being especially the case for larvae of the lotic species. For lentic species, not well adapted to high flow velocity, refuges are thus crucial to escape from drift, while for the lotic species, better adapted to high flow velocity, the structure of the refuge becomes increasingly important. It is concluded that refuges may play a crucial role in restoring and maintaining biodiversity in widened, channelized and flashy lowland streams.


Subject(s)
Biodiversity , Fresh Water/chemistry , Insecta/physiology , Larva/physiology , Rivers/chemistry , Water Movements , Animals , Ecosystem , Population Dynamics
14.
Psychoneuroendocrinology ; 33(6): 863-73, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18472227

ABSTRACT

The human FMR1 gene contains an unstable CGG-repeat in its 5' untranslated region. The repeat length in the normal population is polymorphic (5-54 CGG-repeats). Individuals carrying lengths beyond 200 CGGs (i.e. the full mutation) show hypermethylation and as a consequence gene silencing of the FMR1 gene. The absence of the gene product FMRP causes the fragile X syndrome, the most common inherited form of mental retardation. Elderly carriers of the premutation (PM), which is defined as a repeat length between 55 and 200 CGGs, can develop a progressive neurodegenerative syndrome: fragile X-associated tremor/ataxia syndrome (FXTAS). The high FMR1 mRNA levels observed in cells from PM carriers have led to the hypothesis that FXTAS is caused by a pathogenic RNA gain-of-function mechanism. Apart from tremor/ataxia, specific psychiatric symptoms have been described in PM carriers with or without FXTAS. Since these symptoms could arise from elevated stress hormone levels, we investigated hypothalamic-pituitary-adrenal (HPA) axis regulation using a knock-in mouse model with an expanded CGG-repeat in the PM range (>98 repeats) in the Fmr1 gene, which shows repeat instability, and displays biochemical, phenotypic and neuropathological characteristics of FXTAS. We show elevated levels of corticosterone in serum and ubiquitin-positive inclusions in both the pituitary and adrenal gland of 100-week-old animals. In addition, we demonstrate ubiquitin-positive inclusions in the amygdala from aged expanded CGG-repeat mice. We hypothesize that altered regulation of the HPA axis and the amygdala and higher stress hormone levels in the mouse model for FXTAS may explain associated psychological symptoms in humans.


Subject(s)
Cerebellar Ataxia/physiopathology , DNA Repeat Expansion/genetics , Fragile X Syndrome/physiopathology , Hypothalamo-Hypophyseal System/physiopathology , Pituitary-Adrenal System/physiopathology , Adaptation, Psychological/physiology , Animals , Cerebellar Ataxia/complications , Cerebellar Ataxia/genetics , Corticosterone/metabolism , Disease Models, Animal , Fragile X Mental Retardation Protein/genetics , Fragile X Mental Retardation Protein/metabolism , Fragile X Syndrome/complications , Fragile X Syndrome/genetics , Hypothalamo-Hypophyseal System/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Pituitary-Adrenal System/metabolism , Ubiquitin/metabolism
15.
Reprod Biomed Online ; 16(6): 765-71, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18549684

ABSTRACT

Elevated LH is common in polycystic ovary syndrome (PCOS), but is not part of the diagnostic criteria. LH concentrations are usually assessed in the early 'follicular' phase when it is suppressed, and therefore the prevalence is underestimated. In this study, LH is measured during the 'specific oligomenorrhoeic phase', when LH is least suppressed, and its importance as a diagnostic tool for PCOS is evaluated. Patients presenting with oligo- or amenorrhoea between 2002 and 2006 were selected, with the exclusion of women with WHO III oligoamenorrhoea, hyperprolactinaemia or with wrongly timed endocrine measurements. A total of 252 patients were included (198 oligo/amenorrhoeic PCOS patients and 54 oligo/amenorrhoeic controls). Mean LH concentrations were higher in PCOS patients than in controls (11.0 versus 4.1 IU/l, P < 0.001). The receiver operating characteristics (ROC) curve showed an optimal cut-off for LH of > or =6.5 IU/l, resulting in a sensitivity of 84%, specificity of 78% and a likelihood ratio of 3.8, and elevated LH concentrations predicted PCOS accurately in 93%. In conclusion, elevated LH concentrations are found in a large majority of PCOS patients when measured at the appropriate time, and could be used as an additional diagnostic test to differentiate between oligo/amenorrhoeic PCOS patients and other causes of oligo- or anovulation.


Subject(s)
Amenorrhea/blood , Luteinizing Hormone/blood , Oligomenorrhea/blood , Polycystic Ovary Syndrome/blood , Adult , Amenorrhea/diagnosis , Case-Control Studies , Female , Humans , Oligomenorrhea/diagnosis , Phenotype , Polycystic Ovary Syndrome/diagnosis , ROC Curve
16.
Neth J Med ; 66(7): 292-306, 2008.
Article in English | MEDLINE | ID: mdl-18663260

ABSTRACT

The development of this guideline was initiated and coordinated by the Netherlands Association of Gastroenterologists and Hepatologists (Nederlandse Vereniging van Maag-Darm-Leverartsen). The aim is the establishment of national standards in the evaluation and antiviral treatment of patients with chronic hepatitis B virus (HBV) infection. This includes recommendations on the initial evaluation of patients, choice and duration of antiviral therapy, follow-up after antiviral therapy and monitoring of patients not currently requiring antiviral therapy. The initial evaluation of chronic HBV-infected patients should include testing of liver biochemistry, virus serology and abdominal imaging. In patients without cirrhosis, antiviral treatment is recommended for those with a serum HBV DNA of at least 1.0 x 105 c/ml (>or=2.0 x 10(4) IU/ml) in combination with: a) elevation of serum alanine aminotransferase (ALAT) level above twice the upper limit of normal during at least three months, and/or b) histological evidence of porto-portal septa or interface hepatitis on liver histology. In patients with cirrhosis, antiviral treatment is recommended if serum HBV DNA is 1.0 x 10(4)c/ml (>or=2.0 x 10(3) IU/ml) or higher, independent of ALAT levels or histological findings. If the patient has decompensated cirrhosis, antiviral treatment is recommended if serum HBV DNA is 1000 c/ml (>or=200 IU/ml) or higher. Patients who do not have an indication for antiviral treatment should be monitored because there is a risk of (re)activation of disease activity. Monitoring every three to six months is recommended for HBeAg-positive and HBeAg-negative patients with high viraemia (HBV DNA >or=1.0 x 10(5) c/ml or >or=2.0 x 10(4) IU/ml) and normal ALAT levels. For patients with serum HBV DNA below 1.0 x 10(5) c/ml (<2.0 x 10(4) IU/ml) the recommended frequency of monitoring is every three to six months for HBeAg-positive patients and every six to 12 months for HBeAg-negative patients. Peginterferon (PEG-IF N) therapy should be considered as initial therapy in both HBeAg-positive and HBeAg-negative patients without contraindications for treatment with this drug because of the higher chance of achieving sustained response compared with nucleos(t)ide analogue therapy. In patients starting nucleos(t)ide analogue therapy, the use of lamivudine is not preferred if long-term antiviral treatment is expected due to the high risk of antiviral resistance against this drug. Of the currently licensed nucleos(t)ide analogues, entecavir has the lowest risk of antiviral resistance (compared with lamivudine, adefovir and telbivudine), while suppression of viral replication seems most profound with either entecavir or telbivudine. The recommended duration of treatment with PEG-IF N is one year for both HBeAg-positive and HBeAg-negative patients. In HBeAg-positive patents, nucleos(t)ide analogue therapy should at least be continued until HBeAg seroconversion and a decline in HBV DNA to below 400 c/ml (80 IU/ml) has been achieved and maintained for six months during therapy. Whether nucleos(t)ide analogue therapy can be safely discontinued in HBeAg-negative patients is unknown; usually prolonged or indefinite antiviral treatment is necessary. Patients receiving PEG-IF N should be monitored once a month, while three monthly monitoring suffices for those receiving nucleos(t)ide analogues. Genotypic analysis of the HBV polymerase is indicated if an increase in serum HBV DNA of at least 1 log(10) c/ml (IU/ml) compared with the nadir value is observed during nucleos(t)ide analogue therapy. Antiviral therapy should be changed as soon as possible in case of confirmed genotypic resistance. Adding a second antiviral agent seems beneficial over switching to another agent. With the availability of multiple new antiviral drugs for the treatment of chronic hepatitis B, effective treatment is now possible for more patients and for longer periods. However, the complexity of HBV therapy has also increased. Nowadays, virtually all chronic HBV-infected patients can be effectively managed, either by inducing sustained off-treatment response or by maintaining an on-treatment response.


Subject(s)
Antiviral Agents/therapeutic use , Guidelines as Topic/standards , Hepatitis B, Chronic/drug therapy , Outcome Assessment, Health Care/methods , Humans , Netherlands
17.
Neth J Med ; 66(7): 311-22, 2008.
Article in English | MEDLINE | ID: mdl-18663263

ABSTRACT

The development of this guideline was initiated and coordinated by the Netherlands Association of Gastroenterologists and Hepatologists (Nederlandse Vereniging van Maag-Darm-Leverartsen). The aim is the establishment of practical guidelines in the evaluation and antiviral treatment of patients with chronic hepatitis C virus (HCV) infection. This includes recommendations for the initial evaluation of patients, the choice and duration of antiviral therapy and the follow-up after antiviral therapy. Hepatitis C is a slowly progressive disease. The initial evaluation of chronically HCV-infected patients should include liver biochemistry testing, virological testing and abdominal ultrasound imaging. Liver biopsy is no longer a routine procedure. Antiviral treatment should be considered for all HCV-infected patients. Current antiviral treatment is a long-term process and is associated with substantial side effects. When deciding whether to start treatment or not, the chance of successful treatment (80% with hepatitis C genotype 2 and 3 and 50% with hepatitis C genotype 1 and 4), the fibrosis stage, the expected side effects and the compliance of the patient should be taken into consideration. In the absence of significant fibrosis and necroinflammation in liver biopsy, postponing treatment is an option. Current antiviral treatment is contraindicated in patients with Child-Pugh-class B or C cirrhosis. The possibility of a liver transplantation should be investigated in these patients. Significant comorbidity with a limited life expectancy is an absolute contraindication for antiviral treatment Treatment of chronic hepatitis C consists of administration of peginterferon and ribavirin for 24 or 48 weeks. Patients with hepatitis C genotype 1 or 4 are treated for 48 weeks. Patients with hepatitis C genotype 2 or 3 are treated for 24 weeks. In patients with undetectable HCV RNA after four weeks (28 days) of treatment, a shorter treatment is equally effective (12 to 16 weeks for hepatitis C genotype 2 or 3; 24 weeks for hepatitis C genotype 1 or 4). Outpatient clinic visits are recommended at the start and after 2, 4, 8, and 12 weeks of treatment, and thereafter every four to six weeks until the end of treatment. It is recommended to stop treatment if the HCV RNA level has not decreased by at least 2 log10 IU/ml (c/ml) after 12 weeks of treatment or when HCV RNA is still detectable after 24 weeks of treatment. The recommended frequency of outpatient clinic visits for patients who are not being treated is once every six months in patients with cirrhosis, otherwise every 12 months. It is expected that new anti-HCV-medication (STAT-C, specifically targeted antiviral therapy for HCV) will become available in the near future. Therefore treatment of chronic HCV infection will probably be more effective in the future.


Subject(s)
Antiviral Agents/therapeutic use , Guidelines as Topic/standards , Hepatitis C, Chronic/drug therapy , Outcome Assessment, Health Care/methods , Humans , Netherlands
18.
Ned Tijdschr Geneeskd ; 152(49): 2689-92, 2008 Dec 06.
Article in Dutch | MEDLINE | ID: mdl-19137970

ABSTRACT

A 55-year-old man was admitted to our hospital because of malaise, jaundice en cholestatic liver function impairment, 4 days after his return from vacation in Surinam. Serological tests were positive for IgG and IgM antibodies to hepatitis E virus (HEV) and serum PCR was positive, consistent with HEV infection. The infection was acquired in the Netherlands and not abroad, considering the incubation period. The patient recovered spontaneously. HEV infection is rare in the Netherlands and is associated with travel to tropical or subtropical areas. The virus is transmitted by the faecal-oral route through contaminated water or food. Since 2000 there have been cases reported in the Netherlands, without any association with travelling abroad and in which the infection might be related to zoonotic transmission. The diagnosis is primarily based upon serologic tests for the detection of IgM and IgG antibodies to HEV in serum confirmed by immunoblot. It is important that HEV infection is considered in patients with acute hepatitis in whom no other cause can be found for hepatitis, even without any travel history to endemic areas.


Subject(s)
Antibodies, Viral/blood , Hepatitis E virus/immunology , Hepatitis E virus/isolation & purification , Hepatitis E/diagnosis , Hepatitis E/epidemiology , Humans , Male , Middle Aged , Netherlands/epidemiology , Remission, Spontaneous , Travel
19.
J Mech Behav Biomed Mater ; 80: 209-221, 2018 04.
Article in English | MEDLINE | ID: mdl-29433007

ABSTRACT

Recent studies have shown great potential of Mg matrix composites for biodegradable orthopedic devices. However, the poor structural integrity of these composites, which results in excessive localized corrosion and premature mechanical failure, has hindered their widespread applications. In this research, an in-situ Powder Metallurgy (PM) method was used to fabricate a novel biodegradable Mg-bredigite composite and to achieve enhanced chemical interfacial locking between the constituents by triggering a solid-state thermochemical reaction between Mg and bredigite particles. The reaction resulted in a highly densified and integrated microstructure, which prevented corrosion pits from propagating when the composite was immersed in a physiological solution. In addition, chemical interlocking between the constituents prohibited interparticle fracture and subsequent surface delamination during compression testing, enabling the composite to withstand larger plastic deformation before mechanical failure. Furthermore, the composite was proven to be biocompatible and capable of maintaining its ultimate compressive strength in the strength range of cortical bone after 25-day immersion in DMEM. The research provided the necessary information to guide further research towards the development of a next generation of biodegradable Mg matrix composites with enhanced chemical interlocking.


Subject(s)
Biocompatible Materials/chemistry , Ceramics/chemistry , Magnesium/chemistry , Compressive Strength , Materials Testing
20.
Mol Cell Biol ; 19(1): 934-40, 1999 Jan.
Article in English | MEDLINE | ID: mdl-9858617

ABSTRACT

The nucleotide excision repair (NER) pathway is able to remove a wide variety of structurally unrelated lesions from DNA. NER operates throughout the genome, but the efficiencies of lesion removal are not the same for different genomic regions. Even within a single gene or DNA strand repair rates vary, and this intragenic heterogeneity is of considerable interest with respect to the mutagenic potential of carcinogens. In this study, we have analyzed the removal of the two major types of genotoxic DNA adducts induced by UV light, i.e., the pyrimidine (6-4)-pyrimidone photoproduct (6-4PP) and the cyclobutane pyrimidine dimer (CPD), from the Saccharomyces cerevisiae URA3 gene at nucleotide resolution. In contrast to the fast and uniform removal of CPDs from the transcribed strand, removal of lesions from the nontranscribed strand is generally less efficient and is modulated by the chromatin environment of the damage. Removal of 6-4PPs from nontranscribed sequences is also profoundly influenced by positioned nucleosomes, but this type of lesion is repaired at a much higher rate. Still, the transcribed strand is repaired preferentially, indicating that, as in the removal of CPDs, transcription-coupled repair predominates in the removal of 6-4PPs from transcribed DNA. The hypothesis that transcription machinery operates as the rate-determining damage recognition entity in transcription-coupled repair is supported by the observation that this pathway removes both types of UV photoproducts at equal rates without being profoundly influenced by the sequence or chromatin context.


Subject(s)
DNA Repair , Nucleosomes/genetics , Pyrimidine Dimers/genetics , RNA Polymerase II/metabolism , Saccharomyces cerevisiae/genetics , Transcription, Genetic , Dimerization , Fungal Proteins/genetics , Ultraviolet Rays
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