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Boundary Objects as Dialogical Learning Accelerators for Social Change in Design for Health: Systematic Review. JMIR Hum Factors 2022; 9:e31167. [PMID: 35113023 PMCID: PMC8855288 DOI: 10.2196/31167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 10/15/2021] [Accepted: 10/17/2021] [Indexed: 11/28/2022] Open
Abstract
Background Boundary objects can add value for innovative design and implementation research in health care through their organizational focus and the dynamic structure between ill-structured and tailored use. However, when innovation is approached as a boundary object, more attention will need to be paid to the preimplementation phase. Research and design thinking pay attention to the preimplementation stage but do not have a social or organizational focus per se. The integration of boundary objects in design methodologies can provide a more social and organizational focus in innovative design projects by mapping out the mechanisms that occur at boundaries during design. Four dialogical learning mechanisms that can be triggered at boundaries have been described in the literature: identification, coordination, reflection, and transformation. These mechanisms seem suitable for integration in innovative design research on health. Objective Focusing on innovation in health, this study aims to find out whether the different learning mechanisms can be linked to studies on health innovation that mention boundary objects as a concept and assess whether the related mechanisms provide insight into the stage of the design and implementation or change process. Methods The following 6 databases were searched for relevant abstracts: PubMed, Scopus, Education Resources Information Center, PsycINFO, Information Science and Technology Abstracts, and Embase. These databases cover a wide range of published studies in the field of health. Results Our initial search yielded 3102 records; after removing the duplicates, 2186 (70.47%) records were screened on the title and abstract, and 25 (0.81%) papers were included; of the 13 papers where we identified 1 mechanism, 5 (38%) described an innovation or innovative project, and of the 12 papers where we identified more mechanisms, 9 (75%) described the development or implementation of an innovation. The reflective mechanism was not identified solely but was present in papers describing a more successful development or implementation project of innovation. In these papers, the predetermined goals were achieved, and the process of integration was relatively smoother. Conclusions The concept of boundary objects has found its way into health care. Although the idea of a boundary object was introduced to describe how specific artifacts can fulfill a bridging function between different sociocultural sites and thus have a social focus, the focus in the included papers was often on the boundary object itself rather than the social effect. The reflection and transformation mechanisms were underrepresented in the included studies but based on the findings in this review, pursuing to trigger the reflective mechanism in design, development, and implementation projects can lead to a more fluid and smooth integration of innovation into practice.
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Abstract
Correction to: Surgical and Radiologic Anatomy.
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Reliability of residents' assessments of their postgraduate medical education learning environment: an observational study. BMC MEDICAL EDUCATION 2019; 19:450. [PMID: 31796005 PMCID: PMC6892206 DOI: 10.1186/s12909-019-1874-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 11/15/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Even in anonymous evaluations of a postgraduate medical education (PGME) program, residents may be reluctant to provide an honest evaluation of their PGME program, because they fear embarrassment or repercussions from their supervisors if their anonymity as a respondent is endangered. This study was set up to test the hypothesis that current residents in a PGME program provide more positive evaluations of their PGME program than residents having completed it. We therefore compared PGME learning environment evaluations of current residents in the program to leaving residents having completed it. METHODS This observational study used data gathered routinely in the quality cycle of PGME programs at two Dutch teaching hospitals to test our hypothesis. At both hospitals, all current PGME residents are requested to complete the Scan of Postgraduate Education Environment Domains (SPEED) annually. Residents leaving the hospital after completion of the PGME program are also asked to complete the SPEED after an exit interview with the hospital's independent residency coordinator. All SPEED evaluations are collected and analysed anonymously. We compared the residents' grades (on a continuous scale ranging from 0 (poor) to 10 (excellent)) on the three SPEED domains (content, atmosphere, and organization of the program) and their mean (overall department grade) between current and leaving residents. RESULTS Mean (SD) overall SPEED department grades were 8.00 (0.52) for 287 current residents in 39 PGME programs and 8.07 (0.48) for 170 leaving residents in 39 programs. Neither the overall SPEED department grades (t test, p = 0.53, 95% CI for difference - 0.16 to 0.31) nor the department SPEED domain grades (MANOVA, F(3, 62) = 0.79, p = 0.51) were significantly different between current and leaving residents. CONCLUSIONS Residents leaving the program did not provide more critical evaluations of their PGME learning environment than current residents in the program. This suggests that current residents' evaluations of their postgraduate learning environment were not affected by social desirability bias or fear of repercussions from faculty.
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The Long Non-Coding Rna Chromr Regulates Cholesterol Homeostasis In Primates. Atherosclerosis 2019. [DOI: 10.1016/j.atherosclerosis.2019.06.890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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414 Uncovering the cause of early lethality in generalized severe junctional epidermolysis bullosa. J Invest Dermatol 2019. [DOI: 10.1016/j.jid.2019.03.490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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The Identification and Significance of a Thr→Pro Polymorphism in Kringle IV Type 8 of Apolipoprotein(a). Thromb Haemost 2018. [DOI: 10.1055/s-0038-1656083] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
SummaryElevated plasma levels of lipoprotein(a) [Lp(a)] represent a significant independent risk factor for the development of atherosclerosis. Interindividual levels of apo(a) vary over 1000-fold and are mainly due to inheritance that is linked to the locus of the apolipoprotein(a) [apo(a)] gene. The apo(a) gene encodes multiple repeats of a sequence exhibiting up to 85% DNA sequence homology with plasminogen kringle IV (K.IV), a lysine binding domain. In our search for sequence polymorphisms in the K.IV coding domain, we identified a polymorphism predicting a Thr→Pro substitution located at amino acid position 12 of kringle IV type 8 of apo(a). The functional and clinical significance of this polymorphism was analysed in a case-control study and by comparing the in vitro lysine binding characteristics of the two Lp(a) subtypes.The case-control study (involving 153 subjects having symptomatic atherosclerosis and 153 age and gender matched normolipidemic controls) revealed an overall allele frequency for the Thr12-→Pro substitution in kringle IV type 8 of 14% and a negative association between presence of the Pro12-subtype and symptomatic atherosclerosis (p <0.03). The in vitro lysine binding studies, using Lp(a) isolated from subjects homozygous for either Thr12 or Pro12 in K.IV type 8, revealed comparable lysine-Sepharose binding fractions for the two subtypes. The binding affinity (Kd) for immobilised plasmin degraded des- AA-fibrin (DesafibTM-X) was also comparable for the two subtypes, however a decreased maximal attainable binding (Bmax) for immobilised desafibTM-X was observed for the Pro12-subtype Lp(a).
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Abstract
Summary
Objectives:
Our objectives were to study the temporal correlation of physical activity time series in patients with chronic fatigue syndrome (CFS) during normal daily life and to examine if it could identify the altered physical activity in these patients.
Methods:
Fractal scaling exponents of diurnal and nocturnal physical activity time series in 10 CFS patients and 6 healthy control subjects (CON) were calculated by the detrended fluctuation analysis (DFA) and the wavelet transform modulus maxima (WTMM) method. We hypo-thesized that, due to their illness- and/or fatigue-induced resting episodes, altered physical activity patterns in CFS patients might be observed at the interruption of activity bursts. Thus, we further developed a new method, the wavelet transform negative modulus maxima (WTNMM) method, which could evaluate the temporal correlation at the interruption of activities. We compared the fractal scaling exponents for CFS and CON by each method.
Results:
Both for CFS and CON, we found the fractal time structures in their diurnal physical activity records for at least up to 35 minutes. No group difference was found in nocturnal activities. The WTNMM method revealed that, in diurnal activities, CFS patients had significantly (p <0.01) smaller fractal scaling exponent (0.87 ± 0.03) compared to controls (1.01 ± 0.03). Such a difference was identified neither by the DFA nor WTMM method.
Conclusions:
CFS patients had more abrupt interruptions of voluntary physical activity during diurnal periods in normal daily life, probed by the decreased correlation in the negative modulus maxima of the wavelet-transformed activity data, possibly due to their exaggerated fatigue.
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Improving Spiritual Care in Hospitals in the Netherlands: What Do Health Care Chaplains Involved in an Action-Research Study Report? J Health Care Chaplain 2017; 24:151-173. [PMID: 29166210 DOI: 10.1080/08854726.2017.1393039] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Health care chaplains participated in a multicenter trial to explore an implementation strategy for the Dutch multidisciplinary guideline for spiritual care. The intervention was concise spiritual care training for hospital staff of departments where patients in curative and palliative trajectories are treated. Data were collected in semistructured interviews with chaplains who acted as trainers, before and after the intervention. Results based on nine preintervention and eleven post-intervention interviews are presented. During preintervention interviews, chaplains describe the baseline situation of palliative care in Dutch hospitals, barriers, and opportunities for improving spiritual care. In the postintervention interviews, characteristics of the training, effects, and critical success factors were identified. Positive effects such as lowering barriers, increasing health care professionals' competences, and increasing health care chaplains' profile are possible. Chaplain-led, multidisciplinary spiritual care training is a feasible method to start implementation of spiritual care in hospitals, as described in the multidisciplinary guideline.
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Training hospital staff on spiritual care in palliative care influences patient-reported outcomes: Results of a quasi-experimental study. Palliat Med 2017; 31:743-753. [PMID: 28659006 DOI: 10.1177/0269216316676648] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Spiritual care is reported to be important to palliative patients. There is an increasing need for education in spiritual care. AIM To measure the effects of a specific spiritual care training on patients' reports of their perceived care and treatment. DESIGN A pragmatic controlled trial conducted between February 2014 and March 2015. SETTING/PARTICIPANTS The intervention was a specific spiritual care training implemented by healthcare chaplains to eight multidisciplinary teams in six hospitals on regular wards in which patients resided in both curative and palliative trajectories. In total, 85 patients were included based on the Dutch translation of the Supportive and Palliative Care Indicators Tool. Data were collected in the intervention and control wards pre- and post-training using questionnaires on physical symptoms, spiritual distress, involvement and attitudes (Spiritual Attitude and Involvement List) and on the perceived focus of healthcare professionals on patients' spiritual needs. RESULTS All 85 patients had high scores on spiritual themes and involvement. Patients reported that attention to their spiritual needs was very important. We found a significant ( p = 0.008) effect on healthcare professionals' attention to patients' spiritual and existential needs and a significant ( p = 0.020) effect in favour of patients' sleep. No effect on the spiritual distress of patients or their proxies was found. CONCLUSION The effects of spiritual care training can be measured using patient-reported outcomes and seemed to indicate a positive effect on the quality of care. Future research should focus on optimizing the spiritual care training to identify the most effective elements and developing strategies to ensure long-term positive effects. This study was registered at the Dutch Trial Register: NTR4559.
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Multidisciplinary Training on Spiritual Care for Patients in Palliative Care Trajectories Improves the Attitudes and Competencies of Hospital Medical Staff: Results of a Quasi-Experimental Study. Am J Hosp Palliat Care 2017; 35:218-228. [PMID: 28193104 DOI: 10.1177/1049909117692959] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVES Patients value health-care professionals' attention to their spiritual needs. However, this is undervalued in health-care professionals' education. Additional training is essential for implementation of a national multidisciplinary guideline on spiritual care (SC) in palliative care (PC). Aim of this study is to measure effects of a training program on SC in PC based on the guideline. METHODS A pragmatic multicenter trial using a quasi-experimental pretest-posttest design as part of an action research study. Eight multidisciplinary teams in regular wards and 1 team of PC consultants, in 8 Dutch teaching hospitals, received questionnaires before training about perceived barriers for SC, spiritual attitudes and involvement, and SC competencies. The effect on the barriers on SC and SC competencies were measured both 1 and 6 months after the training. RESULTS For nurses (n = 214), 7 of 8 barriers to SC were decreased after 1 month, but only 2 were still after 6 months. For physicians (n = 41), the training had no effect on the barriers to SC. Nurses improved in 4 of 6 competencies after both 1 and 6 months. Physicians improved in 3 of 6 competencies after 1 month but in only 1 competency after 6 months. SIGNIFICANCE OF RESULTS Concise SC training programs for clinical teams can effect quality of care, by improving hospital staff competencies and decreasing the barriers they perceive. Differences in the effects of the SC training on nurses and physicians show the need for further research on physicians' educational needs on SC.
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Quaking post-transcriptionally promotes differentiation of monocytes into pro-atherogenic macrophages by controling pre-mRNA splicing and gene expression. Atherosclerosis 2016. [DOI: 10.1016/j.atherosclerosis.2016.07.076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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48 Faster restoration of CD4:CD8 ratio during the first 12 weeks of ART initiated at early HIV infection compared with ART initiated at chronic infection in the same patients. J Virus Erad 2016. [DOI: 10.1016/s2055-6640(20)30993-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Comments on ‘Brief screening of patients with distressing fear of recurrence in breast cancer survivors’ by Akechi et al., Breast Cancer Res Treat, 2015, 153(2): pp. 475–476. Breast Cancer Res Treat 2016; 156:203-4. [DOI: 10.1007/s10549-016-3730-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 02/18/2016] [Indexed: 11/25/2022]
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Training general practitioners in early identification and anticipatory palliative care planning: a randomized controlled trial. BMC FAMILY PRACTICE 2015; 16:126. [PMID: 26395257 PMCID: PMC4578268 DOI: 10.1186/s12875-015-0342-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 09/14/2015] [Indexed: 12/25/2022]
Abstract
BACKGROUND Most patients with advanced cancer, debilitating COPD or chronic heart failure (CHF) live at home. General practitioners (GPs) asked for guidance in how to recognize patients in need of palliative care in a timely way and to structure anticipatory care. For that reason, we developed a training for GPs in identifying patients in need of palliative care and in structuring anticipatory palliative care planning and studied its effect on out-of-hours contacts, contacts with their own GP, hospitalizations and place of death. METHODS We performed a cluster randomised controlled trial. GPs in the intervention group were trained in identifying patients in need of palliative care and anticipatory care planning. Next, for each identified patient, they were offered a coaching session with a specialist in palliative care to fine-tune a structured care plan. The GPs in the control group did not receive training or coaching, and were asked to provide care as usual. After one year, characteristics of patients deceased of cancer, COPD or CHF in both study groups were compared with mixed effects models for out-of-hours contacts (primary outcome), contacts with their own GP, place of death and hospitalizations in the last months of their life (secondary outcomes). As a post-hoc analysis, of identified patients (of the intervention GPs) these figures were compared to all other deceased patients, who had not been identified as in need of palliative care. RESULTS We did not find any differences between the intervention and control group. Yet, only half of the trained GPs (28) identified patients (52), which was only 24% of the deceased patients. Those identified patients had significantly more contacts with their own GP (B 4.5218; p <0.0006), were less often hospitalized (OR 0.485; p 0.0437) more often died at home (OR 2.126; p 0.0572) and less often died in the hospital (OR 0.380; p 0.0449). CONCLUSIONS Although we did not find differences between the intervention and control group, we found in a post-hoc analysis that those patients that had been identified as in need of palliative care had more contacts with their GP, less hospitalizations, and more often died at home. We recommend future controlled studies that try to further increase identification of patients eligible for anticipatory palliative care. The Netherlands National Trial Register: NTR2815 date 07-04-2010.
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3443 Severe fatigue in GIST patients: Prevalence, impact and factors associated with fatigue. Eur J Cancer 2015. [DOI: 10.1016/s0959-8049(16)31916-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Subclinical left ventricular dysfunction and 10-year outcomes in type 2 diabetes mellitus. Heart Lung Circ 2015. [DOI: 10.1016/j.hlc.2015.06.587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Economic assessment of Q fever in the Netherlands. Prev Vet Med 2013; 112:27-34. [DOI: 10.1016/j.prevetmed.2013.06.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 05/31/2013] [Accepted: 06/07/2013] [Indexed: 11/24/2022]
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O1-S10.04 Lifestyle as marker of Hepatitis C infection in HIV infected MSM in Amsterdam, The Netherlands. Br J Vener Dis 2011. [DOI: 10.1136/sextrans-2011-050109.58] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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P1-S5.27 Low prevalence of asymptomatic STI in HIV-infected heterosexual males and females, visiting an HIV outpatient clinic in the Netherlands. Br J Vener Dis 2011. [DOI: 10.1136/sextrans-2011-050108.205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Goal orientations and the seeking of different types of feedback information. JOURNAL OF OCCUPATIONAL AND ORGANIZATIONAL PSYCHOLOGY 2010. [DOI: 10.1348/096317906x103410] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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The potential and limitations of DOV 216,303 as a triple reuptake inhibitor for the treatment of major depression: a microdialysis study in olfactory bulbectomized rats. Pharmacol Biochem Behav 2010; 97:444-52. [PMID: 20934452 DOI: 10.1016/j.pbb.2010.10.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Revised: 09/29/2010] [Accepted: 10/03/2010] [Indexed: 01/11/2023]
Abstract
DOV 216,303 belongs to a new class of antidepressants, the triple reuptake inhibitors (TRIs), that blocks serotonin, norepinephrine and dopamine transporters and thereby increases extracellular brain monoamine concentrations. The aim of the present study was to measure extracellular monoamine concentrations both in the prefrontal cortex (PFC) and dorsal hippocampus (DH) after chronic administration of DOV 216,303 in the OBX animal model of depression and to compare the effects with acute drug treatment. OBX animals showed lower dopamine levels in PFC upon acute administration of DOV 216,303 than sham animals for up to five weeks after surgery. No such changes were observed in the DH. Unexpectedly, a DOV 216,303 challenge in chronic DOV 216,303 treated sham animals resulted in a blunted dopamine response in the PFC compared to the same challenge in vehicle treated animals. This blunted response probably reflects pharmacokinetic adaptations and/or pharmacodynamic changes, since brain and plasma concentrations of DOV 216,303 were significantly lower after chronic administration compared to acute administration. Surprisingly, and in contrast what we have reported earlier, chronic DOV 216,303 treatment was unable to normalize the hyperactivity of the OBX animals. Interestingly, by measuring the drug plasma and brain levels, it was demonstrated that at the time of behavioral testing (24 h after last drug treatment) DOV 216,303 was not present anymore in either plasma or brain. This seems to indicate that this putative antidepressant drug has no lasting antidepressant-like behavioral effects in the absence of the drug in the brain.
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Seminal fluid regulates the uterine Foxp3+ T regulatory cell population through CCL19-mediated recruitment during the peri-implantation period in mice. J Reprod Immunol 2010. [DOI: 10.1016/j.jri.2010.06.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Degradation of 2-Chloroethylvinylether by Ancylobacter aquaticus AD25 and AD27. Appl Environ Microbiol 2010; 59:2777-83. [PMID: 16349032 PMCID: PMC182365 DOI: 10.1128/aem.59.9.2777-2783.1993] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Incubation of five different beta-chloroethers with slurries prepared from brackish water sediment or activated sludge revealed that bis(2-chloroethyl)ether and 2-chloroethylvinylether (2-CVE) were biodegradable under aerobic conditions. After enrichment, two different cultures of Ancylobacter aquaticus that are capable of growth on 2-CVE were isolated. Both cultures were also able to grow on 1,2-dichloroethane. The cells contained a haloalkane dehalogenase that dehalogenated 2-CVE, 2-chloroethylmethylether, 2-bromoethylethylether, and epichlorohydrin. Experiments with cell extracts indicated that an alcohol dehydrogenase and an aldehyde dehydrogenase were also involved in the degradation of 2-CVE. This suggests that 2-CVE is metabolized via 2-hydroxyethylvinylether and vinyloxyacetaldehyde to vinyloxyacetic acid. Enzymatic ether cleavage was not detected. 2-CVE was also degraded by chemical ether cleavage, leading to the formation of 2-chloroethanol and acetaldehyde, both of which supported growth. We propose that A. aquaticus strains may be important for the detoxification and degradation of halogenated aliphatic compounds in the environment.
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The effect of a three-year exercise intervention on glycaemic control in patients with type 2 diabetes. J Sci Med Sport 2010. [DOI: 10.1016/j.jsams.2009.10.442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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The effect of a two-year lifestyle intervention on glycaemic control in patients with type 2 diabetes. J Sci Med Sport 2009. [DOI: 10.1016/j.jsams.2008.12.128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Abstract
OBJECTIVES Recent research showed that medical residents have a high risk for developing burnout. The present study investigates the prevalence of burnout and its relationship with suicidal thoughts among medical residents. METHODS All Dutch medical residents (n = 5126) received a self-report questionnaire. Burnout was measured with the Maslach Burnout Inventory. Residents were asked about the frequency of suicidal thoughts. RESULTS Response rate was 41.3% (n = 2115). 432 Residents (20.6%) were classified as burnout. 12% reported having suicidal thoughts at least 1 time during their residency, and 1% many times. Suicidal thoughts were substantially more prevalent in the group with burnout in comparison to non-burnout (20.5% vs. 7.6%; chi(2) = 182.9, p < .001). CONCLUSION Knowledge about the relationship between burnout and suicidal thoughts among these young medical professionals could be important for suicide prevention.
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Preliminary investigation into the response of free cortisol to the low-dose corticotrophin test in patients with septic shock. Crit Care 2008. [PMCID: PMC4088808 DOI: 10.1186/cc6658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Der Einfluss von Insulin auf die Placental Growth Hormone (PGH) – Sekretion von BeWo-Zellen. Geburtshilfe Frauenheilkd 2007. [DOI: 10.1055/s-2007-983557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Effects of a short-term exercise intervention on insulin sensitivity in Type II Diabetes. J Sci Med Sport 2006. [DOI: 10.1016/j.jsams.2006.12.105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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189 Myocardial afterload is significantly elevated post maximal exercise in normotensive patients with Type 2 diabetes mellitus. J Sci Med Sport 2005. [DOI: 10.1016/s1440-2440(17)30685-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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[Withdrawal of fluticasone propionate from combined salmeterol/fluticasone treatment in patients with COPD causes immediate and sustained disease deterioration: a randomised controlled trial]. REVISTA PORTUGUESA DE PNEUMOLOGIA 2005; 11:587-9. [PMID: 16514718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023] Open
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Withdrawal of fluticasone propionate from combined salmeterol/fluticasone treatment in patients with COPD causes immediate and sustained disease deterioration: a randomised controlled trial. Thorax 2005; 60:480-7. [PMID: 15923248 PMCID: PMC1747438 DOI: 10.1136/thx.2004.034280] [Citation(s) in RCA: 192] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Guidelines recommend inhaled corticosteroids (ICS) as maintenance treatment for patients with chronic obstructive pulmonary disease (COPD) with a post-bronchodilator forced expiratory volume in 1 second (FEV1) <50% predicted and frequent exacerbations, although they have only a small preventive effect on the accelerated decline in lung function. Combined treatment with ICS and long acting beta2 agonists (LABA) may provide benefit to the stability of COPD, but it is unknown if withdrawal of ICS will result in disease deterioration. METHODS The effects of 1 year withdrawal of the ICS fluticasone propionate (FP) after a 3 month run-in treatment period with FP combined with the LABA salmeterol (S) (500 microg FP + 50 microg S twice daily; SFC) were investigated in patients with COPD in a randomised, double blind study. 497 patients were enrolled from 39 centres throughout the Netherlands; 373 were randomised and 293 completed the study. RESULTS The drop out rate after randomisation was similar in the two groups. Withdrawal of FP resulted in a sustained decrease in FEV1: mean (SE) change from baseline -4.4 (0.9)% (S) v -0.1 (0.9)% (SFC); adjusted difference 4.1 (95% CI 1.6 to 6.6) percentage points (p<0.001). Corresponding figures for the FEV1/FVC ratio were -3.7 (0.8)% (S) v 0.0 (0.8)% (SFC) (p = 0.002). The annual moderate to severe exacerbation rate was 1.6 and 1.3 in the S and SFC groups, respectively (adjusted rate ratio 1.2; 95% CI 0.9 to 1.5; p = 0.15). The mean annual incidence rate of mild exacerbations was 1.3 (S) v 0.6 (SFC), p = 0.020. An immediate and sustained increase in dyspnoea score (scale 0-4; mean difference between groups 0.17 (0.04), p<0.001) and in the percentage of disturbed nights (6 (2) percentage points, p<0.001) occurred after withdrawal of fluticasone. CONCLUSIONS Withdrawal of FP in COPD patients using SFC resulted in acute and persistent deterioration in lung function and dyspnoea and in an increase in mild exacerbations and percentage of disturbed nights. This study clearly indicates a key role for ICS in the management of COPD as their discontinuation leads to disease deterioration, even under treatment with a LABA.
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Abstract
AIMS/HYPOTHESIS Subclinical left ventricular (LV) dysfunction has been shown by tissue Doppler and strain imaging in diabetic patients in the absence of coronary disease or LV hypertrophy, but the prevalence and aetiology of this finding remain unclear. This study sought to identify the prevalence and the determinants of subclinical diabetic heart disease. METHODS A group of 219 unselected patients with type 2 diabetes without known cardiac disease underwent resting and stress echocardiography. After exclusion of coronary artery disease or LV hypertrophy, the remaining 120 patients (age 57+/-10 years, 73 male) were studied with tissue Doppler imaging. Peak systolic strain of each wall and systolic (Sm) and diastolic (Em) velocity of each basal segment were measured from the three apical views and averaged for each patient. Significant subclinical LV dysfunction was identified according to Sm and Em normal ranges adjusted by age and sex. Strain and Em were correlated with clinical, therapeutic, echocardiographic and biochemical variables, and significant independent associations were sought using a multiple linear regression model. RESULTS Significant subclinical LV dysfunction was present in 27% diabetic patients. Myocardial systolic dysfunction by peak strain was independently associated with glycosylated haemoglobin level (p<0.001) and lack of angiotensin-converting enzyme inhibitor treatment (p=0.003). Myocardial diastolic function (Em) was independently predicted by age (p=0.013), hypertension (p=0.001), insulin (p=0.008) and metformin (p=0.01) treatment. CONCLUSIONS/INTERPRETATION In patients with diabetes mellitus, subclinical LV dysfunction is common and associated with poor diabetic control, advancing age, hypertension and metformin treatment; ACE inhibitor and insulin therapies appear to be protective.
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Accurate classification of protein structural families using coherent subgraph analysis. PACIFIC SYMPOSIUM ON BIOCOMPUTING. PACIFIC SYMPOSIUM ON BIOCOMPUTING 2004:411-22. [PMID: 14992521 DOI: 10.1142/9789812704856_0039] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Protein structural annotation and classification is an important problem in bioinformatics. We report on the development of an efficient subgraph mining technique and its application to finding characteristic substructural patterns within protein structural families. In our method, protein structures are represented by graphs where the nodes are residues and the edges connect residues found within certain distance from each other. Application of subgraph mining to proteins is challenging for a number reasons: (1) protein graphs are large and complex, (2) current protein databases are large and continue to grow rapidly, and (3) only a small fraction of the frequent subgraphs among the huge pool of all possible subgraphs could be significant in the context of protein classification. To address these challenges, we have developed an information theoretic model called coherent subgraph mining. From information theory, the entropy of a random variable X measures the information content carried by X and the Mutual Information (MI) between two random variables X and Y measures the correlation between X and Y. We define a subgraph X as coherent if it is strongly correlated with every sufficiently large sub-subgraph Y embedded in it. Based on the MI metric, we have designed a search scheme that only reports coherent subgraphs. To determine the significance of coherent protein subgraphs, we have conducted an experimental study in which all coherent subgraphs were identified in several protein structural families annotated in the SCOP database (Murzin et al, 1995). The Support Vector Machine algorithm was used to classify proteins from different families under the binary classification scheme. We find that this approach identifies spatial motifs unique to individual SCOP families and affords excellent discrimination between families.
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[Increased serum activity of creatine kinase: usually not a sign of disease]. NEDERLANDS TIJDSCHRIFT VOOR GENEESKUNDE 2004; 148:345-6. [PMID: 15015253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
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Decreased fractal correlation in diurnal physical activity in chronic fatigue syndrome. Methods Inf Med 2004; 43:26-9. [PMID: 15026831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
OBJECTIVES Our objectives were to study the temporal correlation of physical activity time series in patients with chronic fatigue syndrome (CFS) during normal daily life and to examine if it could identify the altered physical activity in these patients. METHODS Fractal scaling exponents of diurnal and nocturnal physical activity time series in 10 CFS patients and 6 healthy control subjects (CON) were calculated by the detrended fluctuation analysis (DFA) and the wavelet transform modulus maxima (WTMM) method. We hypothesized that, due to their illness- and/or fatigue-induced resting episodes, altered physical activity patterns in CFS patients might be observed at the interruption of activity bursts. Thus, we further developed a new method, the wavelet transform negative modulus maxima (WTNMM) method, which could evaluate the temporal correlation at the interruption of activities. We compared the fractal scaling exponents for CFS and CON by each method. RESULTS Both for CFS and CON, we found the fractal time structures in their diurnal physical activity records for at least up to 35 minutes. No group difference was found in nocturnal activities. The WTNMM method revealed that, in diurnal activities, CFS patients had significantly (p < 0.01) smaller fractal scaling exponent (0.87 +/- 0.03) compared to controls (1.01 +/- 0.03). Such a difference was identified neither by the DFA nor WTMM method. CONCLUSIONS CFS patients had more abrupt interruptions of voluntary physical activity during diurnal periods in normal daily life, probed by the decreased correlation in the negative modulus maxima of the wavelet-transformed activity data, possibly due to their exaggerated fatigue.
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The effect of granisetron, a 5-HT3 receptor antagonist, in the treatment of chronic fatigue syndrome patients--a pilot study. Neth J Med 2003; 61:285-9. [PMID: 14692441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
OBJECTIVE To explore the effect of granisetron, a 5-HT3 antagonist, on fatigue and functional impairment in patients with chronic fatigue syndrome (CFS). METHODS Five female patients were eligible to receive oral granisetron for one month (1 mg a day for the first two weeks and 2 mg a day for the second two weeks). The patients had to be between 18 and 65 years of age and suffering from CFS according to the CDC criteria. The effect was assessed by pre- and post-testing, using validated instruments designed to assess the different dimensions of CFS. Treatment response was also evaluated by visual analogue scales (VAS) for fatigue. Analysis was based on intention to treat. RESULTS Treatment with granisetron resulted in significant improvement in fatigue severity and functional impairment. Activity level showed no significant increase. CONCLUSION The promising results of this study have encouraged us to perform a placebo-controlled, double-blind study to evaluate the efficacy of 5-HT3 receptor antagonists in the treatment of CFS.
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[More care for a limited budget; a case for a better use of the efficiency criteria]. NEDERLANDS TIJDSCHRIFT VOOR GENEESKUNDE 2003; 147:134; author reply. [PMID: 12577774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
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Abstract
BACKGROUND Glucose-insulin-potassium (GIK) infusion improves cardiac function and outcome during acute ischaemia. OBJECTIVE To determine whether GIK infusion benefits patients with chronic ischaemic left ventricular dysfunction, and if so whether this is related to the presence and nature of viable myocardium. METHODS 30 patients with chronic ischaemic left ventricular dysfunction had dobutamine echocardiography and were given a four hour infusion of GIK. Segmental responses were quantified by improvement in wall motion score index (WMSI) and peak systolic velocity using tissue Doppler. Global responses were assessed by left ventricular volume and ejection fraction, measured using a three dimensional reconstruction. Myocardial perfusion was determined in 15 patients using contrast echocardiography. RESULTS WMSI (mean (SD)) improved with dobutamine (from 1.8 (0.4) to 1.6 (0.4), p < 0.001) and with GIK (from 1.8 (0.4) to 1.7 (0.4), p < 0.001); there was a similar increment for both. Improvement in wall motion score with GIK was observed in 55% of the 62 segments classed as viable by dobutamine echocardiography, and in 5% of 162 classed as non-viable. There was an increment in peak systolic velocity after both dobutamine echocardiography (from 2.5 (1.8) to 3.2 (2.2) cm/s, p < 0.01) and GIK (from 3.0 (1.6) to 3.5 (1.7) cm/s, p < 0.001). The GIK effects were not mediated by changes in pulse, mean arterial pressure, lactate, or catecholamines, nor did they correlate with myocardial perfusion. End systolic volume improved after GIK (p = 0.03), but only in 25 patients who had viable myocardium on dobutamine echocardiography. CONCLUSIONS In patients with viable myocardium and chronic left ventricular dysfunction, GIK improves wall motion score, myocardial velocity, and end systolic volume, independent of effects on haemodynamics or catecholamines. The response to GIK is observed in areas of normal and abnormal perfusion assessed by contrast echocardiography.
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Prevalence of erectile dysfunction: a systematic review of population-based studies. Int J Impot Res 2002; 14:422-32. [PMID: 12494273 DOI: 10.1038/sj.ijir.3900905] [Citation(s) in RCA: 203] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2002] [Revised: 06/06/2002] [Indexed: 01/23/2023]
Abstract
A systematic review was conducted on the prevalence of erectile dysfunction (ED) in the general population. Studies were retrieved which reported prevalence rates of ED in the general population. Using a specially developed criteria list, the methodological quality of these studies was assessed and data on prevalence rates were extracted. We identified 23 studies from Europe (15), USA (5), Asia (2) and Australia (1). On our 12-item criteria list, the methodological quality ranged from 5 to 12. The prevalence of ED ranged from 2% in men younger than 40 y to 86% in men 80 y and older. Comparison between prevalence data is hampered by major methodological differences between studies, particularly in the use of various questionnaires and different definitions of ED. We stress the importance of providing all necessary information when reporting on the prevalence of ED. Moreover, international studies should be conducted to establish the true prevalence of ED across countries.
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Glucose uptake and insulin action in human adipose tissue--influence of BMI, anatomical depot and body fat distribution. Int J Obes (Lond) 2002; 26:17-23. [PMID: 11791142 DOI: 10.1038/sj.ijo.0801850] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2000] [Revised: 06/12/2001] [Accepted: 07/09/2001] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To examine and compare in vitro basal and insulin-stimulated glucose uptake in human omental and subcutaneous adipose tissue derived from lean, overweight or obese individuals, and in those with central or peripheral obesity. DESIGN In vitro study of basal and insulin-stimulated 2-deoxyglucose uptake in human omental and subcutaneous adipose tissue explants derived from patients undergoing elective abdominal surgery. SUBJECTS Fourteen lean (average age 47 y, average body mass index (BMI) 22 kg/m(2)), 12 overweight (average age 51 y, average BMI 27 kg/m(2)), and 15 obese subjects (average age 45 y, average BMI 39 kg/m(2)). Ten peripherally obese (average age 43 y, average WHR 0.76) and 17 centrally obese (average age 50 y, average waist-to-hip ratio (WHR) 0.92). MEASUREMENTS Fatness and fat distribution parameters (by anthropometry), basal and insulin stimulated [(3)H]-2-deoxyglucose uptake in omental and subcutaneous adipose tissue explants. RESULTS In adipose tissue from lean subjects transport of 2-deoxyglucose over basal was stimulated approximately two-fold by insulin. In contrast, 2-deoxyglucose transport in adipose tissue of obese or overweight subjects was not responsive to insulin. Following incubation with 100-nM insulin for 35 min, insulin-stimulated 2-deoxyglucose transport was significantly lower in both omental and subcutaneous adipose tissue of obese and overweight compared to lean subjects. Basal 2-deoxyglucose uptake was also significantly reduced in omental and subcutaneous tissue in obese compared to lean subjects. Depot-specific differences in 2-deoxyglucose uptake were also seen. Overall 2-deoxyglucose uptake was greater in omental than subcutaneous adipose tissue but this was due to increased basal levels rather than increased insulin action. The reduction in insulin-stimulated 2-deoxyglucose uptake seen in overweight and obese subjects was relatively similar in both depots. However, insulin responsive 2-deoxyglucose transport was significantly lower in the omental adipose tissue of subjects with central obesity, as compared to that of subjects with peripheral obesity. No difference in insulin induced 2-deoxyglucose transport was observed in the subcutaneous adipose tissue explants of subjects with either central or peripheral obesity. CONCLUSION In lean individuals insulin responsiveness of omental and subcutaneous adipose tissue was similar, but basal glucose uptake was significantly higher in omental adipose tissue. Adipose tissue obtained from overweight as well as obese individuals is insulin resistant. This insulin resistance occurs at a lower BMI than previously expected and is not adipose-depot specific. However, in obese subjects with a central distribution of adiposity insulin resistance occurs at the site of omental adipose tissue, in contrast to those with peripheral obesity.
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Kepler, Hobbes and medieval optics. PHILOSOPHIA NATURALIS 2001; 24:287-310. [PMID: 11617919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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[One year of neonatal screening for sickle-cell disease in Emma Children's Hospital/Academic Medical Center in Amsterdam]. NEDERLANDS TIJDSCHRIFT VOOR GENEESKUNDE 2001; 145:1795-9. [PMID: 11582643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
OBJECTIVE Early detection of children with sickle cell disease, determination of carriership frequency as well as evaluation of the knowledge regarding this haemoglobinopathy in various ethnic risk groups. DESIGN Prospective. METHODS From 1 November 1998 through to 31 October 1999, the ethnic background was recorded for consecutive pregnant women under care of the Academic Medical Centre, Amsterdam, the Netherlands, and the presence of carriership for sickle cell disease was evaluated. Carriers were asked about their knowledge of sickle cell disease. A diagnostic blood test of cord blood was also performed using a PCR which could detect both haemoglobin S and C mutations. RESULTS Fifty-five carriers were detected in a group of 1,016 investigated pregnant women (5.4%). The carriership frequencies in Surinam and African women were 12 and 15.7%, respectively. Knowledge of sickle cell disease, its occurrence in populations at risk, as well as the terms 'inheritance' and 'carriership', differed substantially between Surinam and African women, with awareness being lower in the latter group. In six cases informed consent was not asked. All other 49 carriers consented to a diagnostic test. Two intrauterine deaths occurred. Four children had sickle cell disease: three had HbSS, one had HbSC. Nineteen children proved to be carriers for sickle cell disease, 18 were heterozygotes for HbS, one for HbC. CONCLUSION This targeted neonatal screening for sickle cell disease was feasible in a hospital setting. The number of children diagnosed with the disease supports the wider implementation of this method of early detection.
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Fatigue in disease-free cancer patients compared with fatigue in patients with chronic fatigue syndrome. Support Care Cancer 2001; 9:11-7. [PMID: 11147137 DOI: 10.1007/s005200000165] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The goal of our work was to assess fatigue in disease-free cancer patients with help of a validated fatigue questionnaire. Furthermore, we wished to analyse the relationship between severe fatigue and former treatment modalities, problems of concentration and motivation, physical activity, functional impairment, depression and anxiety and finally, to compare severely fatigued disease-free cancer patients and patients with Chronic Fatigue Syndrome (CFS). The participants were 85 adult cancer patients and 16 patients with CFS. The cancer patients were all disease-free and had been off treatment for a minimum of 6 months. They were asked to participate in this study by their physician when they came to the hospital for control visits. Patients who were willing to participate completed four questionnaires. The Checklist Individual Strength was used to measure fatigue. In addition, the Beck Depression Inventory, the Spielberger Trait Anxiety Inventory and the Nottingham Health Profile were used. Results indicate that 19% of the disease-free cancer patients were severely fatigued. Their fatigue experience is comparable to that of patients with CFS. Severe fatigue is associated with problems of concentration and motivation, reduced physical activity, emotional health problems and pain. Furthermore, a relation was found between fatigue and depression and anxiety. No relation was found between fatigue and type of cancer, former treatment modalities, duration of treatment and time since treatment ended. In conclusion, for one fifth of a group of disease-free cancer patients fatigue is a severe problem long after treatment. In addition to fatigue, these patients experience several psychological and physical problems.
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Paraoxonase gene polymorphisms are associated with carotid arterial wall thickness in subjects with familial hypercholesterolemia. Atherosclerosis 2000; 149:371-7. [PMID: 10729387 DOI: 10.1016/s0021-9150(99)00324-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Human serum paraoxonase (PON) is a high density lipoprotein (HDL) associated enzyme capable of hydrolyzing lipid peroxides in vitro. PON has recently attracted attention as a protective factor against oxidative modification of LDL and may therefore play an important role in the prevention of the atherosclerotic process. Two frequent mutations at the paraoxonase gene locus (PON1) are the leucine (L allele)-->methionine (M allele) and the glutamine (Q allele)-->arginine (R allele) substitutions at residues 55 and 192, respectively. We have examined the influence of these two polymorphisms on carotid atherosclerosis in familial hypercholesterolemia (FH) patients. The allele frequencies of these two polymorphisms were determined by PCR and restriction fragment analysis, for both the FH population and healthy controls. High resolution B-mode ultrasound was used to assess intima-media wall thickness (IMT) of the carotid artery. No differences were found in allele frequencies between the FH and the control population. In FH patients, the LL, LM and MM genotypes at position 55 occurred in 86 (46.0%), 78 (41.7%) and 23 (12.3%) subjects, respectively, whereas the QQ, QR and RR genotypes at position 192 were found in 90 (48.1%), 79 (42.2%) and 18 (9.6%) individuals. When both polymorphisms were considered separately, no different carotid IMTs were found between the genotype groups. However, our data did show a significant association between the various genotypes of the combined polymorphisms at position 55 and 192 of PON1 and the carotid artery IMT in FH subjects. Subjects with the homozygous wildtype LL/QQ for paraoxonase had the highest mean carotid IMTs when compared to other genotypes, combined. Multiple regression analysis demonstrated age (beta=0.34, P<0.0001), total plasma cholesterol (beta=0.17, P=0. 0109) and the LL/QQ genotype of the PON1 gene (beta=0.22, P=0.0018) to be significant risk factors for carotid atherosclerosis in subjects with FH. The LL/QQ genotype could explain 5.3% of total variance of carotid IMT. In conclusion, this is the first study to report an independent association between the combined PON1 polymorphism genotypes and carotid wall thickness. The homozygous wildtype LL/QQ for PON1 may represent an additional risk factor for carotid atherosclerosis in subjects with FH.
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The identification of polymorphisms in the coding region of the apolipoprotein (a) gene--association with earlier identified polymorphic sites and influence on the lipoprotein (a) concentration. Thromb Haemost 1999; 82:1709-17. [PMID: 10613659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Lipoprotein (a) [Lp(a)] is a quantitative genetic trait in human plasma and elevated levels represent a major inherited risk factor for the development of atherosclerotic disease. In our search for sequence polymorphisms in the coding region of the apolipoprotein(a) [apo(a)] gene that may affect the Lp(a) concentration, four new polymorphic sites were identified. These include two coinciding polymorphisms with an allele frequency of 38% located at amino acid positions 87 and 101 (Leu87,101-->Val) in the interkringle region of kringle IV (K.IV) type 7 and two polymorphisms located in K.IV type 7 (Arg60-->Ser) and in K.IV type 10 (Tyr2-->Phe) both with estimated allele frequencies of about 1%. The linkage between the newly identified K.IV type 7 Leu87,101 -->Val polymorphism and earlier described polymorphic sites in the non-coding and coding regions of the apo(a) gene, its distribution over the apo(a) isoform sizes and its possible influence on the Lp(a) concentration was analysed in 201 healthy unrelated Caucasians. The earlier described polymorphic sites included in this study were the variable number of a TTTTA pentanucleotide repeat (7-11 PNR) starting at -1231 bp, the -772 bp G/A polymorphism, the +93 bp C/T polymorphism and the +121 bp G/A polymorphism in the non-coding region, and the K.IV type 8 Thr12/Pro polymorphism and the K.IV type 10 Thr66/Met polymorphism in the coding region of the apo(a) gene. Linkage disequilibria were observed between the polymorphic sites in the 5' non-coding region and the sites in K.IV type 7 and 8 in the coding region of the apo(a) gene, confirming that the expansion of the variable number of K.IV type 2 repeats results from intrachromosomal recombinational events. The distribution over the apo(a) isoform sizes of the K.IV type 7 Val87,101 subtype was not significantly different from that of the K.IV type 7 Leu87,101 wild-type, suggesting a relative ancient mutational event. No influence of the K.IV type 7 Leu87,101-->Val polymorphism on the Lp(a) level was observed. In fact, of all the polymorphic sites studied, only the +121 A subtype could be associated with an increased, and the K.IV type 8 Pro12 and the 10 PNR subtypes with a reduced, Lp(a) concentration corrected for apo(a) isoform size (p <0.05).
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