297 research outputs found
Anwendungsbereiche der isothermalen Mikrokalorimetrie in der Urologie: Eine Ãœbersicht
Zusammenfassung: Die isothermale Mikrokalorimetrie (IMC) ist ein nicht spezifisches Wärmemessverfahren. Die hohe Sensitivität des Verfahrens (0,2μW) erlaubt den Nachweis kleinster Wärmemengen z.B. produziert von Mikroorganismen oder eukaryoten Zellen. Ziel dieser Übersichtsarbeit ist es, technische Grundlagen mikrokalorimetrischer Messungen zu vermitteln sowie über Vergangenheit, Gegenwart und Zukunft dieser vielversprechenden Technologie im urologischen Kontext zu berichte
Daylight: What Makes a Difference
Light is necessary for vision; it enables us to sense and perceive our surroundings and in many direct and indirect ways, via eye and skin, affects our physiological and psychological health. The use of light in built environments has comfort, behavioural, economic and environmental consequences. Daylight has many particular benefits including excellent visual performance, permitting good eyesight, effective entrainment of the circadian system as well as a number of acute non-image forming effects and the important role of vitamin D production. Some human responses to daylight seem to be well defined whilst others require more research to be adequately understood. This paper presents an overview of current knowledge on how the characteristics of daylight play a role in fulfilling these and other functions often better than electric lighting as conventionally delivered
Human rhinoviruses enter and induce proliferation of B lymphocytes
Background: Human rhinoviruses (HRVs) are one of the main causes of virus-induced asthma exacerbations. Infiltration of B lymphocytes into the subepithelial tissue of the lungs has been demonstrated during rhinovirus infection in allergic individuals. However, the mechanisms through which HRVs modulate the immune responses of monocytes and lymphocytes are not yet well described. Objective: To study the dynamics of virus uptake by monocytes and lymphocytes, and the ability of HRVs to induce the activation of in vitro-cultured human peripheral blood mononuclear cells. Methods: Flow cytometry was used for the enumeration and characterization of lymphocytes. Proliferation was estimated using 3H-thymidine or CFSE labeling and ICAM-1 blocking. We used bead-based multiplex assays and quantitative PCR for cytokine quantification. HRV accumulation and replication inside the B lymphocytes was detected by a combination of in situ hybridization (ISH), immunofluorescence, and PCR for positive-strand and negative-strand viral RNA. Cell images were acquired with imaging flow cytometry. Results: By means of imaging flow cytometry, we demonstrate a strong and quick binding of HRV types 16 and 1B to monocytes, and slower interaction of these HRVs with CD4+ T cells, CD8+ T cells, and CD19+ B cells. Importantly, we show that HRVs induce the proliferation of B cells, while the addition of anti-ICAM-1 antibody partially reduces this proliferation for HRV16. We prove with ISH that HRVs can enter B cells, form their viral replication centers, and the newly formed virions are able to infect HeLa cells. In addition, we demonstrate that similar to epithelial cells, HRVs induce the production of pro-inflammatory cytokines in PBMCs. Conclusion: Our results demonstrate for the first time that HRVs enter and form viral replication centers in B lymphocytes and induce the proliferation of B cells. Newly formed virions have the capacity to infect other cells (HeLa). These findings indicate that the regulation of human rhinovirus-induced B-cell responses could be a novel approach to develop therapeutics to treat the virus-induced exacerbation of asthma.</p
Desynchronization of Diurnal Rhythms in Bipolar Disorder and Borderline Personality Disorder
It has long been proposed that diurnal rhythms are disturbed in bipolar disorder (BD). Such changes are obvious in episodes of mania or depression. However, detailed study of patients between episodes has been rare and comparison with other psychiatric disorders rarer still. Our hypothesis was that evidence for desynchronization of diurnal rhythms would be evident in BD and that we could test the specificity of any effect by studying borderline personality disorder (BPD). Individuals with BD (n = 36), BPD (n = 22) and healthy volunteers (HC, n = 25) wore a portable heart rate and actigraphy device and used a smart-phone to record self-assessed mood scores 10 times per day for 1 week. Average diurnal patterns of heart rate (HR), activity and sleep were compared within and across groups. Desynchronization in the phase of diurnal rhythms of HR compared with activity were found in BPD (+3 h) and BD (+1 h), but not in HC. A clear diurnal pattern for positive mood was found in all subject groups. The coherence between negative and irritable mood and HR showed a four-cycle per day component in BD and BPD, which was not present in HC. The findings highlight marked de-synchronisation of measured diurnal function in both BD but particularly BPD and suggest an increased association with negative and irritable mood at ultradian frequencies. These findings enhance our understanding of the underlying physiological changes associated with BPD and BD, and suggest objective markers for monitoring and potential treatment targets. Improved mood stabilisation is a translational objective for management of both patient groups
A Note on the Carlson-Parkin Method of Quantifying Qualitative Data
Qualitative surveys enjoy huge popularity among business cycle analysts and research institutes since they provide fast information on the stance of the economy. However, in order to derive quantitative statements researchers have to rely on assumptions about the relation between quantitative and qualitative information. This paper introduces a micro data set that combines individual quantitative and qualitative information and presents first tests of common assumptions. It suggests a modifcation of the Carlson and Parkin (1975) method and a solution to the zero response problem
Circadian profiles in young people during the early stages of affective disorder
Although disturbances of the circadian system are strongly linked to affective disorders, no known studies have examined melatonin profiles in young people in early stages of illness. In this study, 44 patients with an affective disorder underwent clinical and neuropsychological assessments. They were then rated by a psychiatrist according to a clinical staging model and were categorized as having an ‘attenuated syndrome' or an ‘established disorder'. During the evening, salivary melatonin was sampled under dim light conditions over an 8-h interval and for each patient, the time of melatonin onset, total area under the curve and phase angle (difference between time of melatonin onset and time of habitual sleep onset) were computed. Results showed that there was no difference in the timing of melatonin onset across illness stages. However, area under the curve analyses showed that those patients with ‘established disorders' had markedly reduced levels of melatonin secretion, and shorter phase angles, relative to those with ‘attenuated syndromes'. These lower levels, in turn, were related to lower subjective sleepiness, and poorer performance on neuropsychological tests of verbal memory. Overall, these results suggest that for patients with established illness, dysfunction of the circadian system relates clearly to functional features and markers of underlying neurobiological change. Although the interpretation of these results would be greatly enhanced by control data, this work has important implications for the early delivery of chronobiological interventions in young people with affective disorders
Recognition of Crowd Behavior from Mobile Sensors with Pattern Analysis and Graph Clustering Methods
Mobile on-body sensing has distinct advantages for the analysis and
understanding of crowd dynamics: sensing is not geographically restricted to a
specific instrumented area, mobile phones offer on-body sensing and they are
already deployed on a large scale, and the rich sets of sensors they contain
allows one to characterize the behavior of users through pattern recognition
techniques.
In this paper we present a methodological framework for the machine
recognition of crowd behavior from on-body sensors, such as those in mobile
phones. The recognition of crowd behaviors opens the way to the acquisition of
large-scale datasets for the analysis and understanding of crowd dynamics. It
has also practical safety applications by providing improved crowd situational
awareness in cases of emergency.
The framework comprises: behavioral recognition with the user's mobile
device, pairwise analyses of the activity relatedness of two users, and graph
clustering in order to uncover globally, which users participate in a given
crowd behavior. We illustrate this framework for the identification of groups
of persons walking, using empirically collected data.
We discuss the challenges and research avenues for theoretical and applied
mathematics arising from the mobile sensing of crowd behaviors
Recent progress and perspectives of space electric propulsion systems based on smart nanomaterials
Miniaturized spacecraft built from advanced nanomaterials are poised for unmanned space exploration. In this review, the authors examine the integration of nanotechnology in electric propulsion systems and propose the concept of self-healing and adaptive thrusters
Brain Responses to Violet, Blue, and Green Monochromatic Light Exposures in Humans: Prominent Role of Blue Light and the Brainstem
BACKGROUND: Relatively long duration retinal light exposure elicits nonvisual responses in humans, including modulation of alertness and cognition. These responses are thought to be mediated in part by melanopsin-expressing retinal ganglion cells which are more sensitive to blue light than violet or green light. The contribution of the melanopsin system and the brain mechanisms involved in the establishment of such responses to light remain to be established. METHODOLOGY/PRINCIPAL FINDINGS: We exposed 15 participants to short duration (50 s) monochromatic violet (430 nm), blue (473 nm), and green (527 nm) light exposures of equal photon flux (10(13)ph/cm(2)/s) while they were performing a working memory task in fMRI. At light onset, blue light, as compared to green light, increased activity in the left hippocampus, left thalamus, and right amygdala. During the task, blue light, as compared to violet light, increased activity in the left middle frontal gyrus, left thalamus and a bilateral area of the brainstem consistent with activation of the locus coeruleus. CONCLUSION/SIGNIFICANCE: These results support a prominent contribution of melanopsin-expressing retinal ganglion cells to brain responses to light within the very first seconds of an exposure. The results also demonstrate the implication of the brainstem in mediating these responses in humans and speak for a broad involvement of light in the regulation of brain function
Guidelines for the use of flow cytometry and cell sorting in immunological studies (third edition)
The third edition of Flow Cytometry Guidelines provides the key aspects to consider when performing flow cytometry experiments and includes comprehensive sections describing phenotypes and functional assays of all major human and murine immune cell subsets. Notably, the Guidelines contain helpful tables highlighting phenotypes and key differences between human and murine cells. Another useful feature of this edition is the flow cytometry analysis of clinical samples with examples of flow cytometry applications in the context of autoimmune diseases, cancers as well as acute and chronic infectious diseases. Furthermore, there are sections detailing tips, tricks and pitfalls to avoid. All sections are written and peer-reviewed by leading flow cytometry experts and immunologists, making this edition an essential and state-of-the-art handbook for basic and clinical researchers
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