Publications by authors named "Bieber M"

After regulation of pesticides, determination of their persistence in the environment is an important indicator of effectiveness of these measures. We quantified concentrations of two types of systemic insecticides, neonicotinoids (imidacloprid, acetamiprid, clothianidin, thiacloprid, and thiamethoxam) and butenolides (flupyradifurone), in off-crop nontarget media of hummingbird cloacal fluid, honey bee (Apis mellifera) nectar and honey, and wildflowers before and after regulation of imidacloprid on highbush blueberries in Canada in April 2021. We found that mean total pesticide load increased in hummingbird cloacal fluid, nectar, and flower samples following imidacloprid regulation.

View Article and Find Full Text PDF

Despite ongoing research efforts and routine clinical use, the neuronal mechanisms underlying the anesthesia-induced loss of consciousness are still under debate. Unlike most anesthetics, ketamine increases thalamic and cortical activity. Ketamine is considered to act a NMDA-receptor antagonism-mediated reduction of inhibition, i.

View Article and Find Full Text PDF

Background: Ischemic stroke immediately evokes a strong neuro-inflammatory response within the vascular compartment, which contributes to primary infarct development under vessel occlusion as well as further infarct growth despite recanalization, referred to as ischemia/reperfusion injury. Later, in the subacute phase of stroke (beyond day 1 after recanalization), further inflammatory processes within the brain parenchyma follow. Whether this second wave of parenchymal inflammation contributes to an additional/secondary increase in infarct volumes and bears the potential to be pharmacologically targeted remains elusive.

View Article and Find Full Text PDF

In recent decades, the increased use of sensor technologies, as well as the increase in digitalisation of aircraft sustainment and operations, have enabled capabilities to detect, diagnose, and predict the health of aircraft structures, systems, and components. Predictive maintenance and closely related concepts, such as prognostics and health management (PHM) have attracted increasing attention from a research perspective, encompassing a growing range of original research papers as well as review papers. When considering the latter, several limitations remain, including a lack of research methodology definition, and a lack of review papers on predictive maintenance which focus on military applications within a defence context.

View Article and Find Full Text PDF

During ischemic stroke, infarct growth before recanalization diminishes functional outcome. Hence, adjunct treatment options to protect the ischemic penumbra before recanalization are eagerly awaited. In experimental stroke targeting two different pathways conferred protection from penumbral tissue loss: (1) enhancement of hypoxic tolerance of neurons by deletion of the calcium channel subunit Orai2 and (2) blocking of detrimental lymphocyte-platelet responses.

View Article and Find Full Text PDF

In large vessel occlusion stroke, recanalization to restore cerebral perfusion is essential but not necessarily sufficient for a favorable outcome. Paradoxically, in some patients, reperfusion carries the risk of increased tissue damage and cerebral hemorrhage. Experimental and clinical data suggest that endothelial cells, representing the interface for detrimental platelet and leukocyte responses, likely play a crucial role in the phenomenon referred to as ischemia/reperfusion (I/R)-injury, but the mechanisms are unknown.

View Article and Find Full Text PDF

Unlabelled: Detailed information spanning the full annual cycle is lacking for most songbird populations. We examined breeding, migration, and non-breeding sites for the Yellow-breasted Chat ( chat). We deployed archival GPS tags and light-level geolocators on breeding chats in British Columbia and light-level geolocators in California from 2013 to 2017 to determine migration routes and non-breeding sites.

View Article and Find Full Text PDF

Ischemic disorders are the leading cause of death worldwide. The extracellular signal-regulated kinases 1 and 2 (ERK1/2) are thought to affect the outcome of ischemic stroke. However, it is under debate whether activation or inhibition of ERK1/2 is beneficial.

View Article and Find Full Text PDF

In ischemic stroke (IS) impairment of the blood-brain barrier (BBB) has an important role in the secondary deterioration of neurological function. BBB disruption is associated with ischemia-induced inflammation, brain edema formation, and hemorrhagic infarct transformation, but the underlying mechanisms are incompletely understood. Dysfunction of endothelial cells (EC) may play a central role in this process.

View Article and Find Full Text PDF

Objective: Immune responses are an integral part of the complex reactions to acute cerebral ischemia and contribute to infarct expansion and tissue remodeling. Among damage-associated molecular patterns (DAMPs) the high-mobility group box 1 protein (HMGB1) and calprotectin (S100A8/A9) are released from dying cells and activate the innate immune system.

Methods: To assess DAMPs concentrations and related leukocytic infiltration directly and locally in human stroke patients we performed microcatheter sampling from within the core of the occluded vascular compartment before recanalization by mechanical thrombectomy.

View Article and Find Full Text PDF

Patients with atrial fibrillation and previous ischemic stroke (IS) are at increased risk of cerebrovascular events despite anticoagulation. In these patients, treatment with non-vitamin K oral anticoagulants (NOAC) such as edoxaban reduced the probability and severity of further IS without increasing the risk of major bleeding. However, the detailed protective mechanism of edoxaban has not yet been investigated in a model of ischemia/reperfusion injury.

View Article and Find Full Text PDF

Physical inactivity is discussed as one of the most detrimental influences for lifestyle-related medical complications such as obesity, heart disease, hypertension, diabetes and premature mortality in in- and outpatients with major depressive disorder (MDD). In contrast, intervention studies indicate that moderate-to-vigorous-intensity physical activity (MVPA) might reduce complications and depression symptoms itself. Self-reported data on depression [Beck-Depression-Inventory-II (BDI-II)], general habitual well-being (FAHW), self-esteem and physical self-perception (FAHW, MSWS) were administrated in a cross-sectional study with 76 in- and outpatients with MDD.

View Article and Find Full Text PDF

The major depressive disorder is one of the most common mental illnesses worldwide. Current treatment standards recommend a combined therapy with medication and psychotherapy. As an additive component and to further improvements in treatment, physical activity such as yoga may be integrated into conventional treatment.

View Article and Find Full Text PDF

In acute ischemic stroke due to large vessel occlusion (LVO) infarcts rapidly grow into the penumbra, which represents dysfunctional, but still viable brain tissue amenable to rescue by vessel recanalization. However, infarct progression and/or delayed patient presentation are serious and frequent limitations of this so far only acute therapy. Thus, a major goal of translational research is to "freeze" the penumbra already during LVO (before opening the vessel) and thereby extend individual time windows for non-futile recanalization.

View Article and Find Full Text PDF

Based on recent findings that show that depletion of factor XII (FXII) leads to better posttraumatic neurological recovery, we studied the effect of FXII-deficiency on post-traumatic cognitive and behavioral outcomes in female and male mice. In agreement with our previous findings, neurological deficits on day 7 after weight-drop traumatic brain injury (TBI) were significantly reduced in FXII mice compared to wild type (WT) mice. Also, glycoprotein Ib (GPIb)-positive platelet aggregates were more frequent in brain microvasculature of WT than FXII mice 3 months after TBI.

View Article and Find Full Text PDF

The clinical and preclinical research of ischemic strokes (IS) is becoming increasingly comprehensive, especially with the emerging evidence of complex thrombotic and inflammatory interactions. Within these, the blood brain barrier (BBB) plays an important role in regulating the cellular interactions at the vascular interface and is therefore the object of many IS-related questions. Consequently, valid, economic and responsible methods to define BBB integrity are necessary.

View Article and Find Full Text PDF

The excellent craftsmanship of ancient Oriental and Central Asian textile dyers is already demonstrated in the remarkable brilliance and fastness of the colours of the so-called Pazyryk carpet, the by far oldest pile carpet found to date. This specimen resembles the advanced craftsmanship of Iron Age Central Asian textile production. We have employed synchrotron-based µ-XRF imaging to detect the distribution of metal organic pigments within individual fibres of the Pazyryk carpet (about 2500 years old) and compare the results to wool fibres, which we prepared according to traditional Anatolian dyeing recipes.

View Article and Find Full Text PDF

Background: In acute ischemic stroke, cessation of blood flow causes immediate tissue necrosis within the center of the ischemic brain region accompanied by functional failure in the surrounding brain tissue designated the penumbra. The penumbra can be salvaged by timely thrombolysis/thrombectomy, the only available acute stroke treatment to date, but is progressively destroyed by the expansion of infarction. The underlying mechanisms of progressive infarction are not fully understood.

View Article and Find Full Text PDF

Purpose: Cerebral ischemia induces a profound neuro-inflammatory response, but the underlying molecular mechanisms are poorly understood. Inflammasomes (NLRP1, NLRP3, NLRC4, AIM2) are intracellular multi-protein complexes which can induce sets of pro-inflammatory cyto- and chemokines, and thereby guide inflammation. We, here, assessed the functional role of NLRP3 in ischemia/reperfusion (I/R) injury in a mouse model of transient cerebral ischemia.

View Article and Find Full Text PDF

Rationale: Ischemic stroke is a leading cause of morbidity and mortality worldwide. Recanalization of the occluded vessel is essential but not sufficient to guarantee brain salvage. Experimental and clinical data suggest that infarcts often develop further due to a thromboinflammatory process critically involving platelets and T cells, but the underlying mechanisms are unknown.

View Article and Find Full Text PDF

Background and Purpose- The selection of appropriate neurological scores and tests is crucial for the evaluation of stroke consequences. The validity and reliability of neurological deficit scores and tests has repeatedly been questioned in ischemic stroke models in the past. Methods- In 198 male mice exposed to transient intraluminal middle cerebral artery occlusion, we examined the validity and reliability of 11 neurological scores (Bederson score 0-3, Bederson score 0-4, Bederson score 0-5, modified neurological severity [0-14], subjective overall impression [0-10], or simple neurological tests: grip test, latency to move body length test, pole test, wire hanging test, negative geotaxis test, and elevated body swing test) in the acute stroke phase, that is, after 24 hours.

View Article and Find Full Text PDF

Rationale: Giant cell arteritis (GCA) is known to present with typical manifestations like temporal headache and visual abnormalities. However, several cases with atypical manifestations were reported. Stroke occurs in 3% to 7% of patients with GCA.

View Article and Find Full Text PDF

The stereochemistry of the structurally unique myxobacterial polyketides tuscolid/tuscorons was determined by a combination of high-field NMR studies, molecular modeling, and chemical derivatization and confirmed by a modular total synthesis of tuscorons D and E. Together with the discovery of three novel tuscorons, this study provides detailed insight into the chemically unprecedented tuscolid/tuscoron rearrangement cascade.

View Article and Find Full Text PDF
Article Synopsis
  • Platelet interactions with collagen at injury sites primarily involve glycoprotein VI (GPVI) and integrin α2β1, which are critical for stroke pathology.
  • Recent studies indicate that depleting GPVI can improve stroke outcomes without increasing bleeding risk, while high levels of integrin α2 are linked to higher stroke risk.
  • Experiments showed that targeting integrin α2β1 didn't reduce stroke size or improve recovery, but GPVI depletion proved to be an effective and safe intervention in ischemic stroke scenarios.
View Article and Find Full Text PDF

Background and Purpose- Acetylsalicylic acid and clopidogrel are the 2 main antithrombotic drugs for secondary prevention in patients with ischemic stroke (IS) without indication for anticoagulation. Because of their limited efficacy and potential side effects, novel antiplatelet agents are urgently needed. Cilostazol, a specific phosphodiesterase (PDE)-3 inhibitor, protected from IS in clinical studies comprising mainly Asian populations.

View Article and Find Full Text PDF