2,229 research outputs found
Genes Suggest Ancestral Colour Polymorphisms Are Shared across Morphologically Cryptic Species in Arctic Bumblebees
email Suzanne orcd idCopyright: © 2015 Williams et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Revisiting the Dexamethasone Suppression Test in unipolar major depression: an exploratory study
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Advances in prevention and therapy of neonatal dairy calf diarrhoea : a systematical review with emphasis on colostrum management and fluid therapy
Neonatal calf diarrhoea remains the most common cause of morbidity and mortality in preweaned dairy calves worldwide. This complex disease can be triggered by both infectious and non-infectious causes. The four most important enteropathogens leading to neonatal dairy calf diarrhoea are Escherichia coli, rota-and coronavirus, and Cryptosporidium parvum. Besides treating diarrhoeic neonatal dairy calves, the veterinarian is the most obvious person to advise the dairy farmer on prevention and treatment of this disease. This review deals with prevention and treatment of neonatal dairy calf diarrhoea focusing on the importance of a good colostrum management and a correct fluid therapy
Deleterious Effects of Cold Air Inhalation on Coronary Physiological Indices in Patients With Obstructive Coronary Artery Disease
Background
Cold air inhalation during exercise increases cardiac mortality, but the pathophysiology is unclear. During cold and exercise, dual‐sensor intracoronary wires measured coronary microvascular resistance (MVR) and blood flow velocity (CBF), and cardiac magnetic resonance measured subendocardial perfusion.
Methods and Results
Forty‐two patients (62±9 years) undergoing cardiac catheterization, 32 with obstructive coronary stenoses and 10 without, performed either (1) 5 minutes of cold air inhalation (5°F) or (2) two 5‐minute supine‐cycling periods: 1 at room temperature and 1 during cold air inhalation (5°F) (randomized order). We compared rest and peak stress MVR, CBF, and subendocardial perfusion measurements. In patients with unobstructed coronary arteries (n=10), cold air inhalation at rest decreased MVR by 6% (P=0.41), increasing CBF by 20% (P<0.01). However, in patients with obstructive stenoses (n=10), cold air inhalation at rest increased MVR by 17% (P<0.01), reducing CBF by 3% (P=0.85). Consequently, in patients with obstructive stenoses undergoing the cardiac magnetic resonance protocol (n=10), cold air inhalation reduced subendocardial perfusion (P<0.05). Only patients with obstructive stenoses performed this protocol (n=12). Cycling at room temperature decreased MVR by 29% (P<0.001) and increased CBF by 61% (P<0.001). However, cold air inhalation during cycling blunted these adaptations in MVR (P=0.12) and CBF (P<0.05), an effect attributable to defective early diastolic CBF acceleration (P<0.05) and associated with greater ST‐segment depression (P<0.05).
Conclusions
In patients with obstructive coronary stenoses, cold air inhalation causes deleterious changes in MVR and CBF. These diminish or abolish the normal adaptations during exertion that ordinarily match myocardial blood supply to demand
Quantifying Inactive Lithium in Lithium Metal Batteries
Inactive lithium (Li) formation is the immediate cause of capacity loss and
catastrophic failure of Li metal batteries. However, the chemical component and
the atomic level structure of inactive Li have rarely been studied due to the
lack of effective diagnosis tools to accurately differentiate and quantify Li+
in solid electrolyte interphase (SEI) components and the electrically isolated
unreacted metallic Li0, which together comprise the inactive Li. Here, by
introducing a new analytical method, Titration Gas Chromatography (TGC), we can
accurately quantify the contribution from metallic Li0 to the total amount of
inactive Li. We uncover that the Li0, rather than the electrochemically formed
SEI, dominates the inactive Li and capacity loss. Using cryogenic electron
microscopies to further study the microstructure and nanostructure of inactive
Li, we find that the Li0 is surrounded by insulating SEI, losing the electronic
conductive pathway to the bulk electrode. Coupling the measurements of the Li0
global content to observations of its local atomic structure, we reveal the
formation mechanism of inactive Li in different types of electrolytes, and
identify the true underlying cause of low Coulombic efficiency in Li metal
deposition and stripping. We ultimately propose strategies to enable the highly
efficient Li deposition and stripping to enable Li metal anode for next
generation high energy batteries
Autobiographical memory and hierarchical search strategies in depressed and non-depressed participants
Background: There is a growing body of literature showing individuals with depression and other trauma-related disorders (e.g., posttraumatic stress disorder) recall more overgeneral and less specific autobiographical memories compared to normal participants. Although the mechanisms underlying overgeneral memory are quite clear, the search strategy operated within the autobiographical knowledge base, at time of recollection, requires further exploration. The current study aimed to examine the hierarchical search sequence used to recall autobiographical memories in depressed and non-depressed participants, with a view to determining whether depressed participants exhibited truncated search strategies. Methods: Thirteen depressed and an equal number of non-depressed participants retrieved 15 memories each, in response to 15 commonly used cue words. Participants reported the first memory that entered in their mind. All memory descriptions were recorded and later transcribed verbatim for content analysis.Results: Depressed participants retrieved autobiographical memories faster, produced shorter memory descriptions and were less likely to recall positive memories than non-depressed participants. Non-depressed participants were more likely to commence retrieval by accessing lifetime period knowledge followed by general event and event specific knowledge, whereas depressed participants showed a tendency to terminate retrieval at the general event level. Conclusions: It is concluded that depressed participants do adhere to the same hierarchical search strategy as non-depressed participants when retrieving specific autobiographical memories, but that they terminate their search early, resulting in overgeneral memories
Rapid Evaluation in Whole Blood Culture of Regimens for XDR-TB Containing PNU-100480 (Sutezolid), TMC207, PA-824, SQ109, and Pyrazinamide
There presently is no rapid method to assess the bactericidal activity of new regimens for tuberculosis. This study examined PNU-100480, TMC207, PA-824, SQ109, and pyrazinamide, singly and in various combinations, against intracellular M. tuberculosis, using whole blood culture (WBA). The addition of 1,25-dihydroxy vitamin D facilitated detection of the activity of TMC207 in the 3-day cultures. Pyrazinamide failed to show significant activity against a PZA-resistant strain (M. bovis BCG), and was not further considered. Low, mid, and high therapeutic concentrations of each remaining drug were tested individually and in a paired checkerboard fashion. Observed bactericidal activity was compared to that predicted by the sum of the effects of individual drugs. Combinations of PNU-100480, TMC207, and SQ109 were fully additive, whereas those including PA-824 were less than additive or antagonistic. The cumulative activities of 2, 3, and 4 drug combinations were predicted based on the observed concentration-activity relationship, published pharmacokinetic data, and, for PNU-100480, published WBA data after oral dosing. The most active regimens, including PNU-100480, TMC207, and SQ109, were predicted to have cumulative activity comparable to standard TB therapy. Further testing of regimens including these compounds is warranted. Measurement of whole blood bactericidal activity can accelerate the development of novel TB regimens
Oxidative damages in tubular epithelial cells in IgA nephropathy: role of crosstalk between angiotensin II and aldosterone
<p>Abstract</p> <p>Background</p> <p>Inhibition of the renin-angiotensin-aldosterone system (RAAS) slows down the progression of chronic renal diseases (CKD) including IgA nephropathy (IgAN). Herein, we studied the pathogenetic roles of aldosterone (Aldo) in IgAN.</p> <p>Methods</p> <p>Human mesangial cells (HMC) was activated with polymeric IgA (pIgA) from IgAN patients and the effects on the expression of RAAS components and TGF-β synthesis examined. To study the roles of RAAS in the glomerulotubular communication, proximal tubular epithelial cells (PTEC) was cultured with conditioned medium from pIgA-activated HMC with eplerenone or PD123319, the associated apoptotic event was measured by the generation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and reactive oxygen species (ROS).</p> <p>Results</p> <p>Polymeric IgA up-regulated the Aldo synthesis and aldosterone synthase expression by HMC. The release of TGF-β by HMC was up-regulated synergistically by AngII and Aldo and this was inhibited by incubation of HMC with losartan plus eplerenone. Cultured PTEC express the mineralocorticoid receptor, but not synthesizing aldosterone. Apoptosis, demonstrated by cleaved PARP expression and caspase 3 activity, was induced in PTEC activated by conditioned medium prepared from HMC cultured with pIgA from IgAN patients. This apoptotic event was associated with increased generation of NADPH oxidase and ROS. Pre-incubation of PTEC with PD123319 and eplerenone achieved complete inhibition of PTEC apoptosis.</p> <p>Conclusions</p> <p>Our data suggest that AngII and Aldo, released by pIgA activated HMC, served as mediators for inducing apoptosis of PTEC in glomerulo-tubular communications. Crosstalk between AngII and Aldo could participate in determining the tubular pathology of IgAN.</p
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