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1.
Phys Rev Lett ; 130(17): 174001, 2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37172238

ABSTRACT

We report results on the instantaneous drag force on plates that are accelerated in a direction normal to the plate surface, which show that this force scales with the square root of the acceleration. This is associated with the generation and advection of vorticity at the plate surface. A new scaling law is presented for the drag force on accelerating plates, based on the history force for unsteady flow. This scaling avoids previous inconsistencies in using added mass forces in the description of forces on accelerating plates.

2.
Front Sports Act Living ; 5: 1109494, 2023.
Article in English | MEDLINE | ID: mdl-36969962

ABSTRACT

The principal aim of the work presented here is to investigate and demonstrate that a forward tilted rowing blade would result in a more efficient and effective motion of the blade through the water that would result in a higher boat speed when an equal input power is provided. A 1:5 scaled rowing boat is used to determine the performance of rowing blades with different sizes and blade angles. This is used to validate the results of a previous study where the optimal blade angle of 15 ∘ with respect to the oar shaft was determined ( 1). The input power and speed of the rowing boat can be compared between original and modified oar blades. Measurements in a towing tank demonstrate that a modified rowing blade result in faster rowing by 0.4% at the same input power. Maintaining the same stroke rate, the improvement of the blade efficiency is compensated by using a 4-6% increased blade area to yield the same input power.

3.
J Genet Couns ; 27(4): 920-926, 2018 08.
Article in English | MEDLINE | ID: mdl-29372364

ABSTRACT

For couples at high risk of transmitting a cancer predisposition to offspring, reproductive decision-making can be challenging. As the choice between available reproductive options is preference-sensitive, the use of a decision aid can support these couples in their decisional process. The present study aims to investigate preferences and needs of involved stakeholders regarding the development and implementation of a patient decision aid. Semi-structured interviews assessing the needs and preferences regarding the content and functionalities of a decision support program were conducted among seven couples at risk for hereditary cancer and among eight clinical geneticists involved in oncogenetic counseling. Many similarities were found between the expressed preferences and needs of both stakeholder groups concerning the content, barriers and facilitating factors regarding the use of the decision aid, and its implementation. Emphasis was placed on the use of simple non-medical language, an extensive explanation of the procedures and techniques used in prenatal diagnosis (PND) and preimplantation genetic diagnosis (PGD), and the role of health care providers to refer couples to the decision aid. Both stakeholder groups were in favor of incorporating narrative stories in the decision aid. Integrating the present findings with knowledge on reproductive decisional motives and considerations is essential in guiding the development of a decision aid that corresponds to the preferences and needs of end-users. TRIAL REGISTRATION: NTR5467.


Subject(s)
Genetic Counseling/psychology , Genetic Predisposition to Disease/psychology , Neoplastic Syndromes, Hereditary/psychology , Parents/psychology , Preimplantation Diagnosis/psychology , Decision Making , Female , Humans , Male , Neoplastic Syndromes, Hereditary/genetics , Patient Preference , Pregnancy , Prenatal Diagnosis
4.
Eur Rev Med Pharmacol Sci ; 20(20): 4202-4208, 2016 10.
Article in English | MEDLINE | ID: mdl-27831656

ABSTRACT

Ethics has been identified as a key element in Health Technology Assessment (HTA) since its conception. However, ethical issues are still not frequently addressed explicitly in HTA. Several valuable reasons have been identified. The basis of the article is the claim that ethics is often not part of HTA for "epistemological reasons". Hence, the main aim of the contribution is to explore in more details and emphasize them by using the fact/value dichotomy. Our conclusion is that current HTA configuration is predominantly based on the comparison among objective and empirically testable "facts", whilst ethics is not empirically testable. In this sense, there is a sort of "epistemological gap", which can explain why it is so difficult to integrate ethics in HTA. We suggest that the epistemological differences among the various domains of HTA are addressed more explicitly.


Subject(s)
Bioethics , Technology Assessment, Biomedical , Humans
5.
J Consult Clin Psychol ; 84(5): 377-88, 2016 May.
Article in English | MEDLINE | ID: mdl-26950098

ABSTRACT

OBJECTIVE: To determine the efficacy of a cognitive-behavioral intervention for patients meeting U.S. Centers for Disease Control and Prevention (CDC) criteria for idiopathic chronic fatigue (ICF). ICF is thought to be a less severe disorder than chronic fatigue syndrome (CFS). The intervention consisted of a booklet with self-instructions combined with e-mail contact with a therapist. METHOD: Randomized controlled trial conducted at an outpatient facility. All patients suffered from severe and persistent fatigue with moderate impairment levels or fewer than 4 additional symptoms. Patients were randomly allocated to either guided self-instruction or a wait-list control group. Primary outcome measures were fatigue severity assessed with the Checklist Individual Strength and level of overall impairment assessed with the Sickness Impact Profile. Outcome measures were assessed prior to randomization and following treatment or wait-list control group. RESULTS: One hundred patients were randomly allocated to the intervention or a wait-list control group and 95 completed second assessment. An intention-to-treat analysis showed significant treatment effects for fatigue severity (-8.98, 95% confidence interval [CI] [-13.99, -3.97], Cohen's d = 0.68, p < .001) and for overall impairment (-317.19, 95% CI [-481.70, -152.68], Cohen's d = 0.53, p < .01) in favor of the intervention. The number of additional symptoms and overall impairment at baseline did not moderate posttreatment fatigue severity. Baseline overall impairment moderated posttreatment impairment. CONCLUSIONS: Patients with ICF can be treated effectively with a minimal intervention. This is relevant as ICF is more prevalent than CFS and treatment capacity is limited.


Subject(s)
Ambulatory Care , Cognitive Behavioral Therapy , Fatigue Syndrome, Chronic/therapy , Fatigue/prevention & control , Adult , Checklist , Female , Humans , Male , Middle Aged , Netherlands , Severity of Illness Index , Treatment Outcome , Waiting Lists
6.
Int J Obes (Lond) ; 40(4): 654-61, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26499446

ABSTRACT

BACKGROUND: Little is known about epigenetic alterations associated with subcutaneous adipose tissue (SAT) in obesity. Our aim was to study genome-wide DNA methylation and gene expression differences in SAT in monozygotic (MZ) twin pairs who are discordant for body mass index (BMI). This design completely matches lean and obese groups for genetic background, age, gender and shared environment. METHODS: 14We analyzed DNA methylome and gene expression from SAT, together with body composition (magnetic resonance imaging/spectroscopy) and glucose tolerance test, lipids and C-reactive protein from 26 rare BMI-discordant (intrapair difference in BMI ⩾3 kg m(-2)) MZ twin pairs identified from 10 birth cohorts of young adult Finnish twins. RESULTS: We found 17 novel obesity-associated genes that were differentially methylated across the genome between heavy and lean co-twins. Nine of them were also differentially expressed. Pathway analyses indicated that dysregulation of SAT in obesity includes a paradoxical downregulation of lipo/adipogenesis and upregulation of inflammation and extracellular matrix remodeling. Furthermore, CpG sites whose methylation correlated with metabolically harmful fat depots (intra-abdominal and liver fat) also correlated with measures of insulin resistance, dyslipidemia and low-grade inflammation, thus suggesting that epigenetic alterations in SAT are associated with the development of unhealthy obesity. CONCLUSION: This is the first study in BMI-discordant MZ twin pairs reporting genome-wide DNA methylation and expression profiles in SAT. We found a number of novel genes and pathways whose methylation and expression patterns differ within the twin pairs, suggesting that the pathological adaptation of SAT to obesity is, at least in part, epigenetically regulated.


Subject(s)
Body Mass Index , DNA Methylation , Gene Expression Profiling , Obesity/metabolism , Subcutaneous Fat/metabolism , Thinness/metabolism , Twins, Monozygotic , Body Composition/genetics , Female , Finland , Humans , Insulin Resistance/genetics , Male , Obesity/genetics , Obesity/physiopathology , Receptors, Interleukin-6/metabolism , Thinness/genetics , Thinness/physiopathology , Tumor Necrosis Factor-alpha/metabolism , Young Adult
7.
Int J Obes (Lond) ; 40(5): 788-95, 2016 05.
Article in English | MEDLINE | ID: mdl-26601567

ABSTRACT

BACKGROUND: Biotin acts as a coenzyme for carboxylases regulating lipid and amino-acid metabolism. We investigated alterations of the biotin-dependent functions in obesity and the downstream effects of biotin restriction in adipocytes in vitro. SUBJECTS: Twenty-four monozygotic twin pairs discordant for body mass index (BMI). Mean within-pair difference (heavy-lean co-twin, Δ) of BMI was 6.0 kg m(-2) (range 3.1-15.2 kg m(-)(2)). METHODS: Adipose tissue (AT) DNA methylation, gene expression of AT and adipocytes, and leukocytes (real-time quantitative PCR), serum biotin, C-reactive protein (CRP) and triglycerides were measured in the twins. Human adipocytes were cultured in low and control biotin concentrations and analyzed for lipid droplet content, mitochondrial morphology and mitochondrial respiration. RESULTS: The gene expression levels of carboxylases, PCCB and MCCC1, were upregulated in the heavier co-twins' leukocytes. ΔPCCB (r=0.91, P=0.0046) and ΔMCCC1 (r=0.79, P=0.036) correlated with ΔCRP within-pairs. Serum biotin levels were lower in the heavier (274 ng l(-1)) than in the lean co-twins (390 ng l(-1), P=0.034). ΔBiotin correlated negatively with Δtriglycerides (r=-0.56, P=0.045) within-pairs. In AT, HLCS and ACACB were hypermethylated and biotin cycle genes HLCS and BTD were downregulated (P<0.05). Biotin-dependent carboxylases were downregulated (ACACA, ACACB, PCCB, MCCC2 and PC; P<0.05) in both AT and adipocytes of the heavier co-twins. Adipocytes cultured in low biotin had decreased lipid accumulation, altered mitochondrial morphology and deficient mitochondrial respiration. CONCLUSIONS: Biotin-dependent functions are modified by adiposity independent of genetic effects, and correlate with inflammation and hypertriglyceridemia. Biotin restriction decreases lipid accumulation and respiration, and alters mitochondrial morphology in adipocytes.


Subject(s)
Adipocytes/metabolism , Adipose Tissue/metabolism , Adiposity/genetics , Adiposity/physiology , Biotin/metabolism , Lipid Metabolism , Twins, Monozygotic/genetics , Adipose Tissue/cytology , Adult , Amino Acids/genetics , Amino Acids/metabolism , Biotin/genetics , Body Composition/physiology , Body Mass Index , DNA Methylation/physiology , Female , Humans , Lipid Metabolism/genetics , Male , Young Adult
8.
J Eur Acad Dermatol Venereol ; 29(3): 560-5, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25088451

ABSTRACT

BACKGROUND: Drug survival is an indicator for treatment success; insight in predictors associated with drug survival is important. OBJECTIVES (I): To analyse the long-term drug survival for adalimumab in patients with psoriasis treated in daily practice and (II) to identify predictors of prolonged drug survival for adalimumab split for different reasons of discontinuation. METHODS: Data were extracted from a prospective psoriasis cohort and analysed using Kaplan-Meier survival curves split for reasons of discontinuation. Baseline predictors associated with longer drug survival were identified using multivariate Cox-regression analysis. RESULTS: One hundred and sixteen patients were included with a total of 208 patient-years. Overall drug survival was 76% after 1 year and 52% after 4.5 years. In patients who stopped due to ineffectiveness, longer drug survival was associated with the absence of specific comorbidities (P = 0.03). In patients who stopped due to side-effects, longer drug survival was associated with male gender (P = 0.02). CONCLUSIONS: Predictors of adalimumab drug survival in psoriasis differ by reason for discontinuation. Strong, specific predictors can lead to patient-tailored treatment.


Subject(s)
Adalimumab/therapeutic use , Anti-Inflammatory Agents/therapeutic use , Psoriasis/drug therapy , Adult , Female , Humans , Male , Middle Aged , Prospective Studies
10.
Psychol Med ; 42(10): 2205-15, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22354999

ABSTRACT

BACKGROUND: Cognitive behaviour therapy (CBT) for chronic fatigue syndrome (CFS) is an effective but intensive treatment, requiring trained therapists. A minimal intervention based on CBT for CFS, guided self-instruction, was shown to be an effective treatment when delivered in a tertiary treatment centre. Implementing this intervention in a community-based mental health centre (MHC) will increase the treatment capacity for CFS patients. This study evaluated the effectiveness of guided self-instruction for CFS implemented in an MHC, delivered by nurses. METHOD: One hundred and twenty-three patients were randomly assigned to either guided self-instruction (n=62) or a waiting list (n=61). Randomization was computer generated, with allocation by numbered sealed envelopes. Group allocation was open to all those involved. Patients fulfilled US Centers for Disease Control and Prevention (CDC) criteria for CFS. Primary outcome variables were fatigue severity and physical and social functioning, measured with the Checklist Individual Strength (CIS) and the Medical Outcomes Survey Short Form-36 (SF-36) respectively. RESULTS: After 6 months, patients who followed guided self-instruction reported a significantly larger decrease in fatigue compared to the waiting list [mean difference -8.1, 95% confidence interval (CI) -3.8 to -12.4, controlled effect size 0.70]. There was no significant difference in physical and social functioning. However, post-hoc analyses showed a significant decrease in fatigue and physical disabilities following the intervention in a subgroup of patients with physical disabilities at baseline (SF-36 physical functioning ⩽70). CONCLUSIONS: Implementation of guided self-instruction in a community-based MHC was partially successful. The minimal intervention can be effectively implemented for CFS patients with physical impairments.


Subject(s)
Cognitive Behavioral Therapy/methods , Community Mental Health Centers , Fatigue Syndrome, Chronic/therapy , Patient Education as Topic/methods , Programmed Instructions as Topic/statistics & numerical data , Adult , Disabled Persons , Fatigue Syndrome, Chronic/complications , Female , Follow-Up Studies , Health Status , Humans , Male , Netherlands , Patient Education as Topic/statistics & numerical data , Severity of Illness Index , Social Behavior , Stress, Psychological/complications , Surveys and Questionnaires , Treatment Outcome
11.
J Dent Res ; 88(6): 534-8, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19587158

ABSTRACT

UNLABELLED: GoPro49 is a recently identified, novel Golgi protein that is expressed in embryonic mesenchymal tissues, including dental follicle. In the present study, we have tested the hypothesis that the gene is a specific marker for the dental follicle, and examined its expression during the development of mouse incisors and molars. In situ hybridization showed that GoPro49 is expressed in dental follicles from bud to post-eruption stages. The expression is intense throughout the dental follicle during crown development, and persists in the root follicle during root development. In the forming periodontal ligament, GoPro49 expression is down-regulated upon differentiation of the follicle cells to cementoblasts and osteoblasts marked by Bsp1. In cultured dental follicle cells, the GoPro49 protein co-localizes with beta-COP, suggesting that GoPro49 may function in the secretory pathway. We conclude that GoPro49 is a novel, specific marker for the dental follicle and can be used to identify this tissue. ABBREVIATIONS: Bsp1, bone sialoprotein 1; GoPro49, Golgi protein 49 kDa; E16, embryonic day 16; HERS, Hertwig's epithelial root sheath; PDL, periodontal ligament; dpn, day post-natal.


Subject(s)
Dental Sac/metabolism , Golgi Apparatus/metabolism , Membrane Proteins/biosynthesis , Animals , Biomarkers , Cells, Cultured , Coatomer Protein/biosynthesis , Dental Sac/embryology , Dental Sac/growth & development , Gene Expression , Mesoderm/metabolism , Mice , Mice, Inbred Strains , Odontogenesis/genetics , Periodontal Ligament/growth & development
12.
J Dent Res ; 86(11): 1063-7, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17959897

ABSTRACT

Mouse molars are normally not capable of continuous growth. We hypothesized that the mouse molar has intrinsic potential to maintain the epithelial stem cell niche and assessed this potential by growth in vitro. Although the tooth germs flattened considerably, they developed a mineralized crown and a root. However, histologically, the root surface was composed of 3 structurally different regions affecting the fate of the dental epithelium. The anterior and posterior aspects maintained the morphological and molecular characteristics of the cervical loop of a continuously growing incisor, with a continuous layer of ameloblasts. The epithelium making contact with the supporting filter resembled Hertwig's epithelial root sheath. The top of the cultured molar exposed to air lacked epithelium altogether. We conclude that the fate of the epithelium is regulated by external cues influenced by culture conditions, and that the molar has the intrinsic capacity to grow continuously.


Subject(s)
Epithelial Cells/cytology , Gene Expression Regulation, Developmental , Periodontal Ligament/growth & development , Tooth Root/growth & development , Animals , Cell Differentiation , Cell Proliferation , Enamel Organ/cytology , Mice , Mice, Transgenic , Molar/growth & development , Periodontal Ligament/cytology , Receptors, Notch/metabolism , Tissue Culture Techniques , Tooth Germ/cytology , Tooth Root/cytology
13.
Eur J Oral Sci ; 113(4): 312-7, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16048523

ABSTRACT

Notch signaling is an evolutionarily conserved pathway that controls the developmental choices made by individual cells. Cells communicate via Notch receptors and their ligands, which direct decisions on the fate of stem cells according to the states of their neighbors. In this study we explored Notch signaling after the pulp capping of adult first upper rat molars. The wound was capped with calcium hydroxide. In situ hybridization revealed an increased expression of Notch signaling genes on day 1, which showed a tendency to decrease on day 3. Notch1 increased in the subodontoblast zone and close to the lesion limited to a few cells. Notch2 increased in pulp stroma surrounded by coronal odontoblasts. Notch1 and, especially, Notch3 expression increased, corresponding to perivascular cell groups. A low increase of ligand expression was observed near the injury with Delta1 expression along the dentin wall and Jagged1 in the stroma. Expression of the downstream target, Hes1, was observed along the lesion and adjacent dentin walls. Hes5 expression was not observed. The results indicate that Notch signaling is activated in response to injury and associated with the differentiation of pulp cells into perivascular cells and odontoblasts. The findings are consistent with the concept that the Notch pathway controls stem cell fate during pulp regeneration.


Subject(s)
Dental Pulp Capping , Dental Pulp/metabolism , Receptor, Notch2/metabolism , Receptors, Notch/metabolism , Signal Transduction/physiology , Stem Cells/metabolism , Animals , Basic Helix-Loop-Helix Transcription Factors/metabolism , Dental Pulp/cytology , Dental Pulp/injuries , Homeodomain Proteins/metabolism , Intracellular Signaling Peptides and Proteins , Male , Maxilla , Membrane Proteins/metabolism , Molar , Rats , Rats, Wistar , Receptor, Notch1/metabolism , Receptor, Notch3 , Tooth Injuries/metabolism , Transcription Factor HES-1 , Up-Regulation
14.
J Dent Res ; 82(3): 172-6, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12598544

ABSTRACT

Like crown development, root formation is also regulated by interactions between epithelial and mesenchymml tissues. Bone morphogenetic proteins (BMPs), together with the transcription factors Msx1 and Msx2, play important roles in these interactions during early tooth morphogenesis. To investigate the involvement of this signaling pathway in root development, we analyzed the expression patterns of Bmp2, Bmp3, Bmp4, and Bmp7 as well as Msx1 and Msx2 in the roots of mouse molars. Bmp4 was expressed in the apical mesenchyme and Msx2 in the root sheath. However, Bmps were not detected in the root sheath epithelium, and Msx transcripts were absent from the underlying mesenchyme. These findings indicate that this Bmp signaling pathway, required for tooth initiation, does not regulate root development, but we suggest that root shape may be regulated by a mechanism similar to that regulating crown shape in cap-stage tooth germs. Msx2 expression continued in the epithelial cell rests of Malassez, and the nearby cementoblasts intensely expressed Bmp3, which may regulate some functions of the fragmented epithelium.


Subject(s)
Bone Morphogenetic Proteins/genetics , Bone Morphogenetic Proteins/physiology , Cementogenesis/genetics , Dentinogenesis/genetics , Homeodomain Proteins/genetics , Homeodomain Proteins/physiology , Tooth Root/growth & development , Animals , Bone Morphogenetic Protein 3 , Bone Morphogenetic Proteins/biosynthesis , DNA-Binding Proteins/biosynthesis , DNA-Binding Proteins/genetics , DNA-Binding Proteins/physiology , Epithelium/metabolism , Gene Expression Regulation, Developmental , Homeodomain Proteins/biosynthesis , In Situ Hybridization , Integrin-Binding Sialoprotein , MSX1 Transcription Factor , Mesoderm/metabolism , Mice , Mice, Inbred Strains , RNA, Messenger/analysis , Sialoglycoproteins/genetics , Signal Transduction , Tooth Root/metabolism , Transcription Factors/biosynthesis , Transcription Factors/genetics , Transcription Factors/physiology
15.
Z Rechtsmed ; 89(3): 181-9, 1982.
Article in German | MEDLINE | ID: mdl-7158080

ABSTRACT

After oral application of pentacozine (Fortral) besides the unchanged drug some further excretion products were detected by glc/ms in human urine. For their identification e.i.-and c.i.-mass-spectrometry as well as the just recently available FAB-technique were employed. All analyses were performed on a VG-Micromass 7035; the samples were introduced in the ion source via a fused silica, bonded phase capillary column (30 metres; DB-1 J + W, Inc.). The analytical profiles of the pure substance and some metabolites are reported as well as the behaviour of the pure substance on acidic hydrolyzation.


Subject(s)
Gas Chromatography-Mass Spectrometry , Pentazocine/urine , Biotransformation , Forensic Medicine , Humans , Pentazocine/poisoning
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