428 research outputs found
Zum Vorkommen der Wassermollusken in den Augewässern am Unteren Inn (Oberösterreich und Bayern) im Jahr 2005
No full textPatzner, Robert A., Billinger, Florian, Strasser, Thomas (2019): Zum Vorkommen der Wassermollusken in den Augewässern am Unteren Inn (Oberösterreich und Bayern) im Jahr 2005. Linzer biologische Beiträge 51 (2): 1175-1183, DOI: 10.5281/zenodo.374210
A conceptual framework for cautious escalation of anticancer treatment: How to optimize overall benefit and obviate the need for de-escalation trials.
No full textBACKGROUND
The developmental workflow of the currently performed phase 1, 2 and 3 cancer trial stages lacks essential information required for the determination of the optimal efficacy threshold of new anticancer regimens. Due to this there is a serious risk of overdosing and/or treating for an unnecessary long time, leading to excess toxicity and a higher financial burden for society. But often post-approval de-escalation trials for dose-optimization and treatment de-intensification are not performed due to failing resources and time. Therefore, the developmental workflow needs to be restructured toward cautious systemic cancer treatment escalation, in order to guarantee optimal efficacy and sustainability.
METHODS
In this manuscript we discuss opportunities to produce the information needed for cautious escalation, based on models of cancer growth and cancer kill kinetics as well as exploratory biomarkers, for the purpose of designing the optimal phase 3 superiority trial. Subsequently, we compare the sample size needed for a phase 3 superiority trial, followed by a necessary de-escalation trial with the sample size needed for a multi-arm phase 3 trial with intervention arms of differing intensity. All essential items are structured within a Framework for Cautious Escalation (FCE). The discussion uses illustrations from the breast cancer setting, but aims to be applicable for all cancers.
RESULTS
The FCE is a promising model of clinical development in oncology to prevent overtreatment and associated issues, especially with regard to the number of repetitive treatment cycles. It will hopefully increase the relevance and success rate of clinical trials, to deliver improved patient-centric outcomes
Author comment on RC4: 'Review of Strasser et al.: Rofental catchment', Adam Winstral, 02 Oct 2017
No full textThe New Paternalism
No full textThe author argues that the belief that patient autonomy has great
moral value has justified a new form of medical paternalism which can have
effects similar to those of the old rejected form. He cites the argument that
"all illness represents a state of diminished autonomy" and that therefore
autonomy is not overridden when physicians make all decisions. Another view
is that, in some situations, withholding information may prevent patient
deterioration and loss of autonomy. Abridgement of present autonomy, then, is
permissible if it promotes future autonomy. Strasser also rejects physician
decision making based on patients' previously communicated values or on the
theory that patient values are important but not decisive. He concludes that
if we "allow paternalistic practices, then we should admit that we are denying
autonomy in light of some other good rather than claim that, somehow, we are
respecting autonomy by abridging it." (KIE abstract
Fatigue in palliative care patients - an EAPC approach
No full textFatigue is one of the most frequent symptoms in palliative care patients, reported in 80% of cancer patients and in up to 99% of patients following radio- or chemotherapy. Fatigue also plays a major role in palliative care for noncancer patients, with large percentages of patients with HIV, multiple sclerosis, chronic obstructive pulmonary disease or heart failure reporting fatigue. This paper presents the position of an expert working group of the European Association for Palliative Care (EAPC), evaluating the available evidence on diagnosis and treatment of fatigue in palliative care patients and providing the basis for future discussions. As the expert group feels that culture and language influence the approach to fatigue in different European countries, a focus was on cultural issues in the assessment and treatment of fatigue in palliative care. As a working definition, fatigue was defined as a subjective feeling of tiredness, weakness or lack of energy. Qualitative differences between fatigue in cancer patients and in healthy controls have been proposed, but these differences seem to be only an expression of the overwhelming intensity of cancer-related fatigue. The pathophysiology of fatigue in palliative care patients is not fully understood. For a systematic approach, primary fatigue, most probably related to high load of proinflammatory cytokines and secondary fatigue from concurrent syndromes and comorbidities may be differentiated. Fatigue is generally recognized as a multidimensional construct, with a physical and cognitive dimension acknowledged by all authors. As fatigue is an inherent word only in the English and French language, but not in other European languages, screening for fatigue should include questions on weakness as a paraphrase for the physical dimension and on tiredness as a paraphrase for the cognitive dimension. Treatment of fatigue should include causal interventions for secondary fatigue and symptomatic treatment with pharmacological and nonpharmacological interventions. Strong evidence has been accumulated that aerobic exercise will reduce fatigue levels in cancer survivors and patients receiving cancer treatment. In the final stage of life, fatigue may provide protection and shielding from suffering for the patient and thus treatment may be detrimental. Identification of the time point, where treatment of fatigue is no longer indicated is important to alleviate distress at the end of life
The covariance structure of conditional maximum likelihood estimates
No full textIn this paper we consider conditional maximum likelihood (cml) estimates for
item parameters in the Rasch model under random subject parameters. We give
a simple approximation for the asymptotic covariance matrix of the cml-estimates.
The approximation is stated as a limit theorem when the number of item parameters
goes to infinity. The results contain precise mathematical information on the order
of approximation.
The results enable the analysis of the covariance structure of cml-estimates when
the number of items is large. Let us give a rough picture. The covariance matrix has
a dominating main diagonal containing the asymptotic variances of the estimators.
These variances are almost equal to the efficient variances under ml-estimation when
the distribution of the subject parameter is known. Apart from very small numbers
n of item parameters the variances are almost not affected by the number n. The
covariances are more or less negligible when the number of item parameters is large.
Although this picture intuitively is not surprising it has to be established in precise
mathematical terms. This has been done in the present paper.
The paper is based on previous results [5] of the author concerning conditional
distributions of non-identical replications of Bernoulli trials. The mathematical background
are Edgeworth expansions for the central limit theorem. These previous results
are the basis of approximations for the Fisher information matrices of cmlestimates.
The main results of the present paper are concerned with the approximation
of the covariance matrices.
Numerical illustrations of the results and numerical experiments based on the
results are presented in Strasser, [6]. (author's abstract
Overcoming barriers to timely recognition and treatment of cancer cachexia: Sharing Progress in Cancer Care Task Force Position Paper and Call to Action
No full textCachexia is a life-threatening disorder affecting an estimated 50-80% of cancer patients. The loss of skeletal muscle mass in patients with cachexia is associated with an increased risk of anticancer treatment toxicity, surgical complications and reduced response. Despite international guidelines, the identification and management of cancer cachexia remains a significant unmet need owing in part to the lack of routine screening for malnutrition and suboptimal integration of nutrition and metabolic care into clinical oncology practice. In June 2020, Sharing Progress in Cancer Care (SPCC) convened a multidisciplinary task force of medical experts and patient advocates to examine the barriers preventing the timely recognition of cancer cachexia, and provide practical recommendations to improve clinical care. This position paper summarises the key points and highlights available resources to support the integration of structured nutrition care pathways
Author comment on RC2: 'Review of : “The Rofental: a high Alpine research basin (1890 m – 3770m a.s.l.) in the Ötztal Alps (Austria) with over 150 years of hydro-meteorological and glaciological observations” by Ulrich Strasser et. al.', Stefan Poh
No full text- …
