217 research outputs found
Accurate Targeting of Liver Tumors in Stereotactic Radiation Therapy
This doctoral thesis concerns the treatment of liver cancer patients using
external beam radiotherapy. The quality of this treatment greatly depends
on delivering a high radiation dose to the tumor while keeping the dose as
low as possible to surrounding healthy tissues. One of the major
challenges is locating the tumor at the moment of dose delivery. In this
ork, the uncertainty of locating the tumor was investigated. For this
purpose, gold markers were implanted in the liver tissue and visualized on
X-ray images. The markers were used to measure day-to-day tumor mobility
and motion
due to respiration. Furthermore, it was found that major improvements in
the targeting accuracy can be achieved by using the markers for guiding
the treatment procedure
Negative symptoms predict high relapse rates and both predict less favorable functional outcome in first episode psychosis, independent of treatment strategy
BACKGROUND: In first episode psychosis (FEP) baseline negative symptoms (BNS) and relapse both predict less favorable functional outcome. Relapse-prevention is one of the most important goals of treatment. Apart from discontinuation of antipsychotics, natural causes of relapse are unexplained. We hypothesized that BNS, apart from predicting worse functional outcome, might also increase relapse risk. METHODS: We performed a post-hoc analysis of 7-year follow-up data of a FEP cohort (n = 103) involved in a dose-reduction/discontinuation (DR) vs. maintenance treatment (MT) trial. We examined: 1) what predicted relapse, 2) what predicted functional outcome, and 3) if BNS predicted relapse, whether MT reduced relapse rates compared to DR. After remission patients were randomly assigned to DR or MT for 18 months. Thereafter, treatment was uncontrolled. OUTCOMES: BNS and duration of untreated psychosis (DUP) predicted relapse. Number of relapses, BNS, and treatment strategy predicted functional outcome. BNS was the strongest predictor of relapse, while number of relapses was the strongest predictor of functional outcome above BNS and treatment strategy. Overall and within MT, but not within DR, more severe BNS predicted significantly higher relapse rates. Treatment strategies did not make a difference in relapse rates, regardless of BNS severity. INTERPRETATION: BNS not only predicted worse functional outcome, but also relapses during follow-up. Since current low dose maintenance treatment strategies did not prevent relapse proneness in patients with more severe BNS, resources should be deployed to find optimal treatment strategies for this particular group of patients
Reprint of:Negative symptoms predict high relapse rates and both predict less favorable functional outcome in first episode psychosis, independent of treatment strategy
Background: In first episode psychosis (FEP) baseline negative symptoms (BNS) and relapse both predict less favorable functional outcome. Relapse-prevention is one of the most important goals of treatment. Apart from discontinuation of antipsychotics, natural causes of relapse are unexplained. We hypothesized that BNS, apart from predicting worse functional outcome, might also increase relapse risk. Methods: We performed a post-hoc analysis of 7-year follow-up data of a FEP cohort (n = 103) involved in a dose-reduction/discontinuation (DR) vs. maintenance treatment (MT) trial. We examined: 1) what predicted relapse, 2) what predicted functional outcome, and 3) if BNS predicted relapse, whether MT reduced relapse rates compared to DR. After remission patients were randomly assigned to DR or MT for 18 months. Thereafter, treatment was uncontrolled. Outcomes: BNS and duration of untreated psychosis (DUP) predicted relapse. Number of relapses, BNS, and treatment strategy predicted functional outcome. BNS was the strongest predictor of relapse, while number of relapses was the strongest predictor of functional outcome above BNS and treatment strategy. Overall and within MT, but not within DR, more severe BNS predicted significantly higher relapse rates. Treatment strategies did not make a difference in relapse rates, regardless of BNS severity. Interpretation: BNS not only predicted worse functional outcome, but also relapses during follow-up. Since current low dose maintenance treatment strategies did not prevent relapse proneness in patients with more severe BNS, resources should be deployed to find optimal treatment strategies for this particular group of patients. (C) 2019 Elsevier B.V. All rights reserved
Supported Housing and Supported Independent Living in the Netherlands, with a Comparison with England
Research into community housing programs for people with severe mental illness is underexposed. The Dutch UTOPIA study describes characteristics of their service users, which may predict their allocation to either supported housing or supported independent living programs. Additionally, a comparison is made with English studies. 119 Care coordinators of Dutch residential care institutes and 534 service users participated in a cross-sectional survey which includes socio-demographic data, clinical data, measures of functioning, needs for care and quality of life. Differences between Dutch residents and independent living service users were small, making predictions of care allocation difficult. This similarity suggests a possible lack of methodical assessment in the allocation procedure of people who are eligible for residential housing or independent living programs. This is largely comparable to the English situation. In comparison with their English counterparts, Dutch service users have more met needs and are more engaged in occupational activities
The Validity of the 16-Item Version of the Prodromal Questionnaire (PQ-16) to Screen for Ultra High Risk of Developing Psychosis in the General Help-Seeking Population
In order to bring about implementation of routine screening for psychosis risk, a brief version of the Prodromal Questionnaire (PQ; Loewy et al., 2005) was developed and tested in a general help-seeking population. We assessed a consecutive patient sample of 3533 young adults who were help-seeking for nonpsychotic disorders at the secondary mental health services in the Hague with the PQ. We performed logistic regression analyses and CHi-squared Automatic Interaction Detector decision tree analysis to shorten the original 92 items. Receiver operating characteristic curves were used to examine the psychometric properties of the PQ-16. In the general help-seeking population, a cutoff score of 6 or more positively answered items on the 16-item version of the PQ produced correct classification of Comprehensive Assessment of At-Risk Mental State (Yung et al., 2005) psychosis risk/clinical psychosis in 44% of the cases, distinguishing Comprehensive Assessment of At-Risk Mental States (CAARMS) diagnosis from no CAARMS diagnosis with high sensitivity (87%) and specificity (87%). These results were comparable to the PQ-92. The PQ-16 is a good self-report screen for use in secondary mental health care services to select subjects for interviewing for psychosis risk. The low number of items makes it quite appropriate for screening large help-seeking populations, thus enhancing the feasibility of detection and treatment of ultra high-risk patients in routine mental health services. © The Author 2012
Comparative activity of tedizolid and glycopeptide combination therapies for the treatment of Staphylococcus aureus infections: an in vitro and in vivo evaluation against strains with reduced susceptibility to glycopeptides
Investigator Initiated Research Grant from Merck Sharpe and Dohme Ltd
A Smart Screening Device for Patients with Mental Health Problems in Primary Health Care:Development and Pilot Study
BACKGROUND: Adequate recognition of mental health problems is a prerequisite for successful treatment. Although most people tend to consult their general practitioner (GP) when they first experience mental health problems, GPs are not very well equipped to screen for various forms of psychopathology to help them determine clients' need for treatment. OBJECTIVE: In this paper, the development and characteristics of CATja, a computerized adaptive test battery built to facilitate triage in primary care settings, are described, and first results of its implementation are reported. METHODS: CATja was developed in close collaboration with GPs and mental health assistants (MHAs). During implementation, MHAs were requested to appraise clients' rankings (N=91) on the domains to be tested and to indicate the treatment level they deemed most appropriate for clients before test administration. We compared the agreement between domain score appraisals and domain score computed by CATja and the agreement between initial (before test administration) treatment level advice and final treatment level advice. RESULTS: Agreements (Cohen kappas) between MHAs' appraisals of clients' scores and clients' scores computed by CATja were mostly between .40 and .50 (Cohen kappas=.10-.20), and the agreement between "initial" treatment levels and the final treatment level advised was .65 (Cohen kappa=.55). CONCLUSIONS: Using CATja, caregivers can efficiently generate summaries of their clients' mental well-being on which decisions about treatment type and care level may be based. Further validation research is needed
Ethnicity and baseline symptomatology in patients with an At Risk Mental State for psychosis
Ethnicity has been associated with different incidence rates and different symptom profiles in young patients with psychotic-like disorders. No studies so far have examined the effect of ethnicity on symptoms in people with an At Risk Mental State (ARMS). In this cross-sectional study, we analysed the relationship between ethnicity and baseline data on the severity of psychopathology scores in 201 help-seeking patients who met the ARMS criteria and agreed to participate in the Dutch Early Detection and Intervention (EDIE-NL) trial. Eighty-seven of these patients had a non-Dutch ethnicity. We explored the possible mediating role of ethnic identity. Higher rates of negative symptoms, and of anhedonia in particular, were found in the ethnic minority group. This result could be attributed mainly to the Moroccan-Dutch and Turkish-Dutch subgroups, who also presented with more depression symptoms when the groups were examined separately. The ethnic minority group displayed a lower level of ethnic group identity compared to the immigrants of the International Comparative Study of Ethnocultural Youth (ICSEY). Ethnic identity was inversely related to symptoms in the Moroccan-Dutch patient group. The prevalence of more severe negative symptoms and depression symptoms in ethnic minority groups deserves more attention, as the experience of attenuated positive symptoms when accompanied by negative symptoms or distress has proven to be predictive for transition to a first psychotic episod
Searching for the optimal number of response alternatives for the distress scale of the four-dimensional symptom questionnaire
BACKGROUND: The Four-Dimensional Symptom Questionnaire (4DSQ) is a self-report questionnaire designed to measure distress, depression, anxiety, and somatization. Prior to computing scale scores from the item scores, the three highest response alternatives ('Regularly', 'Often', and 'Very often or constantly present') are usually collapsed into one category to reduce the influence of extreme responding on item- and scale scores. In this study, we evaluate the usefulness of this transformation for the distress scale based on a variety of criteria. METHODS: Specifically, by using the Graded Response Model, we investigated the effect of this transformation on model fit, local measurement precision, and various indicators of the scale's validity to get an indication on whether the current practice of recoding should be advocated or not. In particular, the effect on the convergent- (operationalized by the General Health Questionnaire and the Maastricht Questionnaire), divergent- (operationalized by the Neuroticism scale of the NEO-FFI), and predictive validity (operationalized as obtrusion with daily chores and activities, the Biographical Problem list and the Utrecht Burnout Scale) of the distress scale was investigated. RESULTS: Results indicate that recoding leads to (i) better model fit as indicated by lower mean probabilities of exact test statistics assessing item fit, (ii) small (<.02) losses in the sizes of various validity coefficients, and (iii) a decrease (DIFF (SE's) = .10-.25) in measurement precision for medium and high levels of distress. CONCLUSIONS: For clinical applications and applications in longitudinal research, the current practice of recoding should be avoided because recoding decreases measurement precision for medium and high levels of distress. It would be interesting to see whether this advice also holds for the three other domains of the 4DSQ
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