370 research outputs found
Frequencies of myeloid-derived suppressor cells in relation to the cytotoxic T cell response in HIV-infected patients of the New Era Study
The HIV infection is a serious health burden that affects almost 38 million people worldwide. Thanks to extensive research, the infection has become manageable for patients under a continuous highly active antiretroviral treatment but a cure has not been found up to now. This thesis investigated the effects of treatment intensification on the immune system of HIV patients of the New Era Study (NE). This involved 5 antiretroviral drugs over a minimal duration of 5 years with the long-term objective of reaching a functional cure of HIV. One subgroup received the 5-drug regimen during the chronic stage (CHI) whereas the other subgroup started during primary infection (PHI). Results were compared within the two NE subgroups and to other HIV groups, including progressors, patients under a conventional cART and natural controllers. On the one hand, this study focused on the effect of treatment on the two subsets of myeloid-derived suppressor cells (MDSCs), namely PMN-MDSC and M-MDSC. On the other hand, the effect on CD8 T cell responses specific to two proteins of HIV, Gag and Nef, was studied. Possible correlations between the immunosuppressive cells and the HIV-specific CD8 T cell responses were also tested.
Intriguingly, the results for MDSCs and immune responses were similar in the NE cohort and patients under cART. Thus, it was not possible to postulate an advantage for the treatment intensification. Furthermore, a clear advantage for the patients with an early treatment start could not be interpreted from the results either. The impact of antiretroviral treatment appeared to be greater on the PMN-MDSC subset as it led to almost normal levels. In contrast, the frequency of M-MDSCs remained significantly higher in comparison to healthy individuals. Although MDSCs are known to exert their suppressive function on T cells, there were no correlations found between the two subsets of MDSCs and the HIV-specific CD8 T cells investigated.
In the NE patients, the level of MDSCs was comparable to those of the conventional cART-treated patients. However, NE patients revealed a surprisingly broad CD8 T cell response which might imply a higher degree of immune preservation in this group of patients.Die HIV-Infektion ist eine ernstzunehmende Erkrankung, die nahezu 38 Millionen Menschen weltweit betrifft. Dank des Forschungsfortschrittes lÀsst sich die Infektion heutzutage mit einer kontinuierlichen hochaktiven antiretroviralen Therapie behandeln. Allerdings ist eine Heilung der Erkrankung bislang nicht möglich.
Diese Arbeit untersuchte die Effekte einer Therapieintensivierung auf das Immunsystem von HIV Patienten der New Era Studie (NE). Hierbei wurden 5 antiretrovirale Medikamente ĂŒber einen Zeitraum von mindestens 5 Jahren verabreicht mit dem Ziel langfristig eine funktionale Heilung der Infektion zu erreichen. Eine Gruppe erhielt das Therapieregime aus 5 Medikamenten wĂ€hrend der chronischen Phase der Infektion (CHI), wohingegen eine weitere Gruppe wĂ€hrend der akuten Phase begann (PHI). Die Ergebnisse wurden zwischen diesen beiden Gruppen verglichen sowie mit weiteren HIV Gruppen. Darunter befanden sich Patienten mit einer fortgeschrittenen Infektion ("Progressor"), Patienten mit einem konventionellen Therapieansatz und "HIV Controller". Einerseits beschĂ€ftigte sich diese Arbeit mit dem Effekt der Behandlung auf die zwei Untergruppen der Myeloid-derived suppressor cells (MDSCs), nĂ€mlich den PMN-MDSC und M-MDSC. Andererseits wurde der Effekt von spezifischen CD8-T-Zell Antworten auf zwei HIV Proteine Gag und Nef untersucht. AuĂerdem wurden mögliche Korrelationen zwischen den immunsuppressiven Zellen und den HIV-spezifischen CD8-T-Zell Antworten ĂŒberprĂŒft.
Interessanterweise waren die Ergebnisse fĂŒr die MDSCs und die Immunantworten der NE Kohorte vergleichbar mit den Ergebnissen der Patienten unter konventionellem Therapieansatz. Daher konnte in diesem Zusammenhang kein Vorteil fĂŒr die Intensivierung der Therapie gezeigt werden. Desweiteren konnte kein klarer Vorteil fĂŒr die Patienten mit einem frĂŒhen Behandlungsbeginn aus den Ergebnissen interpretiert werden. Die antiretrovirale Therapie schien sich stĂ€rker auf die PMN-MDSC Untergruppe auszuwirken, da hier nahezu normale Level erreicht wurden. Dagegen war die Frequenz der M-MDSCs im Vergleich zu den gesunden Probanden signifikant erhöht. Obwohl MDSCs fĂŒr ihre suppressive Funktion auf T-Zellen bekannt sind, konnten keine Korrelationen zwischen den zwei Untergruppen der MDSCs und den HIV-spezifischen CD8-T-Zellen gefunden werden.
Die Level der MDSCs waren vergleichbar zwischen den NE Patienten und den Patienten unter einer konventionellen Therapie mit cART. Allerdings zeigten die NE Patienten ĂŒberraschend breite CD8-T-Zell Antworten, was auf einen höheren Grad der Erhaltung des Immunsystems dieser Patientengruppe schlieĂen lassen könnte
Ecological sustainability in rangelands : the contribution of dung beetles in secondary seed dispersal (case study: Chaharmahal and Bakhtiari province, Iran)
Ecological sustainability has been recognized as one of the main aspects of sustainable development of rangelands, at which different kinds of animal including insects, make substantial contributions. Dung beetles, known as dung-visiting insects, play several key roles in many ecological functions from which benefit both terrestrial ecosystems and human population. Specifically, they benefit rangelands through reducing greenhouse gas emission, nutrient cycling, plant growth enhancement, trophic regulation and pollination and secondary seed dispersal. This study examined secondary seed dispersal as one of the ecological functions of dung beetles, in Chaharmahal and Bakhtiari province, Iran. We applied an experimental approach to measure ecological function (i.e. seed removal) by functional groups of dung beetles. We tested whether functional dung beetle groups influence secondary seed dispersal differently. Through repeated standardized samples of sheep dung, data obtained regularly during two different months August and November in 2013. The results show that dung beetles play a role in secondary seed dispersal. However, it is affected by seed size, so that seed removal increased in the order of, large, medium and small size, respectively. The significant differences between treatments were found for small seeds in the both months. More seeds were dispersed from treatment t02 (all combinations of functional groups except large rollers) in August, while in November more seeds from treatments t01 (dwellers plus large and small tunnelers plus large and small rollers) and t03 (the combinations of dwellers plus small tunnelers, and small rollers) were removed. As a conclusion, it is suggested that if it is to guarantee the ecological sustainability of rangelands, paying attention to the ecological functions of dung beetles is crucial
Dynamic NanoSIMS ion imaging of unicellular freshwater algae exposed to copper
This work demonstrates the capabilities of nanoscale secondary-ion mass spectrometry, using the Cameca NanoSIMS50 ion microprobe, to detect and image the copper-ion distribution in microalgal cells exposed to nanomolar and micromolar copper concentrations. In parallel to 63Cuâ secondary-ion maps, images of 12Câ, 12C14Nâ, and 31Pâ secondary ions were collected and analysed. A correlation of 63Cuâ secondary-ion maps with those found for 12C14Nâ and 31Pâ demonstrated the possible association of Cu with cell components rich in proteins and phosphorus. The results highlighted the potential of NanoSIMS for intracellular tracking of essential trace elements such as Cu in single cells of the microalga Chlorella kesslerii. Figure 12C14N-, 63Cu- secondary-ion distributions in algal cel
INFOGEST Digestion Assay of Raw and Roasted Hazelnuts and Its Impact on Allergens and Their IgE Binding Activity
Most of the food allergens sensitized via the gastrointestinal tract resist thermal treatments and digestion, particularly digestion by pepsin. Roasted hazelnuts are more commonly consumed than raw ones. Since no studies have characterized gastric digestion protein fragments of raw and roasted hazelnuts nor their IgE binding properties, we compared these aspects of raw and roasted hazelnutsâ gastric digesta obtained by INFOGEST protocol. Their electrophoretically resolved profiles were probed with hazelnut allergic patientsâ sera in 1D and 2D immunoblots. Electrophoretic profiles demonstrated pepsin digestion of all hazelnut allergens to varying extents. While 2D immunoblots indicated that roasting slightly reduced allergenicity, IgE ELISA with the pool of sera showed a slight significant (10%) increase in IgE binding in both gastric digesta. Cor a 9 isolated from the raw and roasted hazelnuts, characterized by far and near CD, remained stable after roasting, with preserved IgE reactivity. Its immunoreactivity contribution by inhibitory ELISA was noticeable in raw and roasted hazelnut digesta; its activity was slightly stronger in the roasted preparations. Roasting has a visible impact on proteins; however, it did not affect overall IgE reactivity. Gastric digestion slightly increases the overall IgE reactivity in raw and roasted hazelnuts, and may therefore impact the profiles of allergens and their fragments available to interact with the immune system in the small intestine
Allergome of oral-gastric in vitro digest of roasted hazelnut shows stronger IgE binding compared to the raw counterpart
Background: In vitro pepsin digestion is important factor when assessing protein food
allergenicity. Roasted hazelnut is more common in human nutrition than a raw hazelnut;
however, all studies were focused on Cor a 9 allergen obtained from a raw hazelnut. There
are only two studies employing in vitro INFOGEST digestion harmonized protocol on
hazelnut with its full matrix. The aim of this study was to assess immunoreactivity of raw
and roasted hazelnut gastric digests and to compare secondary/tertiary structure of Cor a 9
allergen purified from these two sources.
Methods: Digestion resistant protein fragments were analysed by 1D/2D electrophoresis.
Following digestion, IgE binding from patientsâ pooled sera and by specific antibodies, were
assessed in ELISA and immunoblot. CD spectroscopy was applied for Cor a 9 structural
analyses.
Results: Cor a 11 and acidic forms of Cor a 9 were more prone to pepsin proteolysis, yet
their large fragments survived partially. Cor a 8 was protected by lipids, retaining capability
to bind its specific antibody. Roasting did not significantly affect secondary structure of the
most abundant hazelnut allergen, Cor a 9.
Conclusion: Roasting of hazelnut seems to boost IgE binding derived from pooled sera of
hazelnut allergic patients with oral-gastric allergen digests.Related to Book of Abstracts: [https://www.cost-infogest.eu/content/download/4051/35805/file/V-ICFD%20Book%20of%20Abstracts.pdf]Related to record of lecture: [https://www.youtube.com/watch?v=Dj0_1fyY724
Analysis of rotorcraft wind turbine wake encounters using piloted simulation
The use of offshore wind farms in Europe to provide a sustainable alternative energy source is now considered normal. Particularly in the North Sea, a large number of wind farms exist with a significant distance from the coast. This is becoming standard practice as larger areas are required to support operations. Efficient transport and monitoring of these wind farms can only be conducted using helicopters. As wind turbines continue to grow in size, there is a need to continuously update operational requirements for these helicopters, to ensure safe operations. This study assesses German regulations for flight corridors within offshore wind farms. A semi-empirical wind turbine wake model is used to generate velocity data for the research flight simulator AVES. The reference offshore wind turbine NREL 5 MW has been used and scaled to represent wind turbine of different sizes. This paper reports result from a simulation study concerning vortex wake encounter during offshore operations. The results have been obtained through piloted simulation for a transport case through a wind farm. Both subjective and objective measures are used to assess the severity of vortex wake encounters
Influence of immune activity of Cor a 9 from raw and roasted hazelnuts after gastric digestion
Cor a 9 is one of the most common hazelnut allergen, a non-glycosylated protein, consisting of two subunits, an acidic (ranging between 35-40 kDa) and a basic subunit (ranging between 20-25 kDa). Very important fact is that the acid chain carries the immunoreactivity, according to literature. The survival of large fragments of Cor a 9 is necessary for its ability to sensitize individual. The aim of this study was to investigate Cor a 9, and to compare the digestive stability and allergenicity of large and small peptides released after pepsin digestion of whole raw and roasted hazelnut grains in standardized and physiologically relevant in vitro conditions, after heat treatment (roasting as the most abundant type of heat treatment). In vitro simulated phases of oral and gastric digestion were performed with ground raw and roasted hazelnut kernels according to the 1.0 INFOGEST protocol. After digestion proteins were extracted from the digestion mixture and analysed by 1D and 2D SDS-PAGE, while their IgE test was examined in the sera of allergic patients using ELISA and 2D immunoblot. The focus of the research was on the analysis of the 2DE map by Image 2D Master Platinum 7.0 software, comparing region of acid and basic Cor a 9 from raw and roasted hazelnut. Cor a 9 peptides are resistant to gastric digestion, and are able to bind IgE patients. Roasted hazelnuts are more prone to digestion in the stomach than the raw sample and cause a milder IgE response in patients. The gastric digestion phase of raw and roasted hazelnut grains resulted in partial extraction and digestion of Cor a 9 into digestion-resistant peptides with preserved IgE-binding epitopes. These results show significant resistance of Cor a 9 raw and roasted hazelnuts to digestion in the stomach, as they remained mostly intact after 2 hours of gastric (pepsin) phase and retained their allergenicity
Influence of Raw and Roasted Hazelnut Food Matrix on Ige Binding Activity After Application of the Harmonized Static Digestion Protocol
Most of the hazelnut proteins are resistant to proteolysis in the gastrointestinal tract, and the survival
of their large fragments are essential for their sensitizing capacity. Usually, studies were carried out
on purified proteins, paying no attention to the potential impact of the food matrix and thermal
treatment on allergenicity. Obtained hazelnut peptides after gastric digestion, especially those with
potential IgE binding epitopes, highlight the need for further studies on their IgE reactivity. The aim
of this study was to investigate and compare digestion stability and allergenicity of large and small
peptides released after pepsin digestion of whole raw and roasted hazelnut kernels under standardized
and physiologically relevant in vitro conditions, after thermal treatment (roasting as most abundant
type of thermal treatment). In vitro simulated oral and gastric phase digestion was carried out with
ground raw and roasted hazelnut kernels according to INFOGEST protocol. Digested proteins were
extracted from the digestion mixture and analysed by 1D and 2D SDS-PAGE, while their IgE biding
was probed with allergic patientsâ sera via ELISA and 2D immunoblot. The most abundant hazelnut
allergens within 2DE map were acidic and basic chains of Cor a 9 and Cor a 11. Digestion-resistant
peptides of Cor a 11 and Cor a 9 were able to bind patientsâ IgE. Roasted hazelnut is more prone to
gastric digestion than the raw sample, and cause milder IgE response in patients. Gastric phase
digestion of raw and roasted hazelnut kernels resulted in partial extraction and digestion of Cor a 11
and Cor a 9 into digestion-resistant peptides with preserved IgE-binding epitopes. These results
demonstrate substantial resistance of raw and roasted hazelnut allergens to gastric digestion since
they remained mostly intact after 2 h of gastric (pepsin) phase and retained their allergenicity
Frequency and predictors of unspecific medical diagnoses in the emergency department: a prospective observational study.
BACKGROUND
Misdiagnosis is a major public health problem, causing increased morbidity and mortality. In the busy setting of an emergency department (ED) patients are diagnosed under difficult circumstances. As a consequence, the ED diagnosis at hospital admittance may often be a descriptive diagnosis, such as "decreased general condition". Our objective was to determine in how far patients with such an unspecific ED diagnosis differ from patients with a specific ED diagnosis and whether they experience a worse outcome.
METHODS
We conducted a prospective observational study in Bern university hospital in Switzerland for all adult non-trauma patients admitted to any internal medicine ward from August 15th 2015 to December 7th 2015. Unspecific ED diagnoses were defined through the clinical classification software for ICD-10 by two outcome assessors. As outcome parameters, we assessed in-hospital mortality and length of hospital stay.
RESULTS
Six hundred eighty six consecutive patients were included. Unspecific diagnoses were identified in 100 (14.6%) of all consultations. Patients receiving an unspecific diagnosis at ED discharge were significantly more often women (56.0% vs. 43.9%, pâ=â0.024), presented more often with a non-specific complaint (34% vs. 21%, pâ=â0.004), were less often demonstrating an abnormal heart rate (5.0% vs. 12.5%, pâ=â0.03), and less often on antibiotics (32.0% vs. 49.0%, pâ=â0.002). Apart from these, no studied drug intake, laboratory or clinical data including change in diagnosis was associated significantly with an unspecific diagnosis. Unspecific diagnoses were neither associated with in-hospital mortality in multivariable analysis (ORâ=â1.74, 95% CI: 0.60-5.04; pâ=â0.305) adjusted for relevant confounders nor with length of hospital stay (GMRâ=â0.87, 95% CI: 0.23-3.32; pâ=â0.840).
CONCLUSIONS
Women and patients with non-specific presenting complaints and no abnormal heart rate are at risk of receiving unspecific ED diagnoses that do not allow for targeted treatment, discharge and prognosis. This study did not find an effect of such diagnoses on length of hospital stay nor in-hospital mortality
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