Cdc48/p97 is an essential and highly conserved AAA+ ATPase that uses its protein-unfoldase activity to extract ubiquitinated polypeptides from macromolecular complexes and membranes. This motor has ...also been implicated in protein-degradation pathways, yet its exact role in acting upstream of the 26S proteasome remains elusive. Ubiquitinated proteins destined for degradation by the proteasome require an unstructured initiation region to engage with the proteasomal translocation machinery, and Cdc48 was proposed to generate these unfolded segments, yet direct evidence has been missing. Here, we used an in vitro reconstituted system to demonstrate the collaboration of Cdc48 and the 26S proteasome from
.
in degrading ubiquitinated, well-folded proteins that lack unstructured segments. Our data indicate that a critical role for Cdc48 in the ubiquitin-proteasome system is to create flexible initiation regions in compact substrates that otherwise would be refractory to engagement and degradation by the proteasome.
The increase in volume in bio-waste is inseparable from the production of biomass derived commodities. To reduce the use of conventional resources, the valorization of waste streams is gaining ...importance, and the valorisation of poultry litter fits perfectly into such scheme. This study shows a possible valorization of wet torrefied (300 °C) poultry litter (WTPL) through activation and its further use as a fertilizer, and as a wastewater micro-pollutant absorbent. The WTPL was activated thermally, physically (CO2) and chemically (KOH) at two different temperatures (600 °C and 800 °C) and 30 min residence time. The properties of ACs were evaluated based on results of the elemental and proximate analysis, suspension pH measurement, ICP-OES, FT-IR, N2 and CO2 adsorption and quantity of absorbed methylene blue (MB). The yields in thermal and physical ACs were comparable, but much higher than ACs from chemical activation (c.a. 50% and 15% at 600 °C and c.a. 47% and 6.5% at 800 °C). The thermal and physical ACs showed good suitability for application as a fertilizer due to their high macro- and micro-nutrients and low heavy metals concentration. Carbons activated with KOH proved their usefulness as wastewater pollutant absorbers through high MB's absorption (675.8 mg/g for 600 °C and 872.8 mg/g for 800 °C). Results state that the valorization of PL through activation is possible, and the selection of the activation method affects the final application of obtained material.
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•Activated carbon were produced by three different activating treatments.•The relation between pH in contact and ash composition of the ACs was studied.•Chemical activation removed most of the inorganics of the initial WTPL.
We introduce a model of vortices in type-II superconductors with a four-fold anisotropy in the vortex-vortex interaction potential. Using numerical simulations we show that the vortex lattice ...undergoes structural transitions as the anisotropy is increased, with a triangular lattice at low anisotropy, a rhombic intermediate state, and a square lattice for high anisotropy. In some cases we observe a multi-q state consisting of an Archimedean tiling that combines square and triangular local ordering. At very high anisotropy, domains of vortex chain states appear. We discuss how this model can be generalized to higher order anisotropy as well as its applicability to other particle-based systems with anisotropic particle-particle interactions.
•The first investigation of alveolar macrophage phenotypes in horses with severe equine asthma.•In horses with equine asthma, alveolar macrophages have a non-canonical M1/M2 phenotype.•The ...non-canonical phenotype of equine asthma persists during clinical remission induced by pasturing.•Healthy horses develop a similar non-canonical phenotype only during hay feeding in a stable.
Because the alveolar macrophage (AM) phenotype of horses with severe equine asthma (SEA) is unknown, the cytokines expressed by M1- and M2-polarized AM were determined and the hypothesis that natural hay/straw challenge (NC) induces divergent AM phenotypes in control horses and horses with SEA was tested. Macrophages from control horses were activated either with eIFNγ + lipolysaccharide (LPS) or eIL-4 to characterize M1- or M2-polarized AM gene expression, respectively and determine the response of polarized cells to pathogen-associated molecular patterns (PAMPS): LPS, zymosan, peptidoglycan and hay dust. Subsequently, gene expression was explored in AM of control horses and horses with SEA at pasture and after NC.
M1 polarization increased expression of pro-inflammatory cytokines (TNFα, IL-8, IL-12p40), IL-10, and CD80. M2 polarization increased CD206 and down-regulated arginase-II and IL-10. Expression of pro-inflammatory cytokines and CD80 in response to PAMPS was further increased by M1 pre-polarization whereas M2 pre-polarization down-regulated expression of pro-inflammatory cytokines and IL-10 but increased CD206. In horses with SEA, AMs had elevated expression of IL-10 both at pasture and after NC, but only after NC in control horses. CD206 expression increased in both groups during NC. At pasture, stimulation by PAMPS augmented expression of IL-8 and IL-10 in horses with SEA compared to control horses. NC eliminated this difference by selectively increasing expression of IL-10 in control horses. A fundamental shift in the macrophage phenotype in SEA is supported by consistently elevated production of IL-10. A similar non-canonical phenotype develops temporarily in control horses upon NC suggesting that AMs in horses with SEA have lost the ability to respond dynamically to environmental cues.
p53 as an unstable protein in vitro likely requires stabilizing factors to act as a tumor suppressor in vivo. Here, we show that in human cells transfected with wild-type (WT) p53, Hsp90 and Hsp70 ...molecular chaperones maintain the p53 native conformation under heat-shock conditions (42 degrees C) as well as assist p53 refolding at 37 degrees C, during the recovery from heat shock. We also show that the interaction of WT p53 with WAF1 promoter in cells is sensitive to Hsp70 and Hsp90 inhibition already at 37 degrees C and further decreased on heat shock. The influence of chaperones on p53 binding to the WAF1 promoter sequence has been confirmed in vitro, using highly purified proteins. Hsp90 stabilizes the binding of p53 to the promoter sequence at 37 degrees C, whereas under heat-shock conditions the requirement for the Hsp70-Hsp40 system and its cooperation with Hsp90 increases. Hop co-chaperone additionally stimulates these reactions. Interestingly, the combined Hsp90 and Hsp70-Hsp40 allow for a limited in vitro restoration of the DNA-binding activity by the p53 oncogenic variant R249S and affect its conformation in cells. Our results indicate for the first time that, especially under stress conditions, not only Hsp90 but also Hsp70 is required for the chaperoning of WT and R249S p53.
We report on (13)C spin-lattice (R 1) and spin-spin (R 2) relaxation rate dependence on magic-angle-spinning (MAS) rate in highly purified synthetic nanodiamonds. Noticeable slowdown of both ...relaxation processes and reduction of nuclear spin diffusion coefficient D with increasing MAS rate was obtained. This effect is attributed to suppression of nuclear spin diffusion by MAS. We developed a theoretical approach that describes the MAS rate dependence of R 1, R 2 and D, allows quantitative analysis of the data and shows good compliance with the experiment.
Starting in the 1950s, physicians and researchers began to debate the exact nature of the relationship among blood cholesterol, diet, and cardiovascular risk. Using professional medical, public ...health, and scientific journals, this article examines the history of a series of intense and sustained debates regarding the credibility of the diet-heart hypothesis, which proposed that diet was causally linked to coronary artery disease. Brought about by intellectual disagreements and illuminated by personal quarrels, these debates created a profound professional rift among researchers who debated whether observational data could be used to prove that dietary intake caused heart disease and who sought to differentiate between "good" and "bad" science. But while the debate persisted into the early 1980s, Americans had begun to adopt the diet-heart hypothesis as public health truth as early as the 1960s, embracing cookbooks promoting "heart healthy" diets that promised to prevent coronary artery disease. Although critics and advocates of diet-heart continued to debate the theory's finer points, the widespread adoption of diet-heart in American homes meant that the debate had become almost moot by the time the National Heart, Lung, and Blood Institute officially endorsed the hypothesis in the 1980s.
We report on the first nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) study of the high-temperature nanodiamond-to-onion transformation. 1H, 13C NMR and EPR spectra of the ...initial nanodiamond samples and those annealed at 600, 700, 800 and 1800 ° C were measured. For the samples annealed at 600 to 800 ° C, our NMR data reveal the early stages of the surface modification, as well as a progressive increase in sp2 carbon content with increased annealing temperature. Such quantitative experimental data were recorded for the first time. These findings correlate with EPR data on the sensitivity of the dangling bond EPR line width to air content, progressing with rising annealing temperature, that evidences consequent graphitization of the external layers of the diamond core. The sample annealed at 1800 ° C shows complete conversion of nanodiamond particles into carbon onions.
Before the 20th century, peripheral artery disease (PAD) manifested as extreme pain, chronic wounds, and, eventually, gangrene requiring amputation. Despite this, it was rarely diagnosed. However, at ...the turn of the century, Western medicine shifted focus from infectious to chronic illnesses, and with this change, physicians’ engagement with PAD transformed. Aiming to mitigate long-term injury, physicians now worked to identify and treat vessel disease to restore meaningful blood circulation. This article explores the development and deployment of a new device resulting from this refocus, the PAssive VAscular EXerciser (PAVAEX) Boot, and its role as a creative response to a previously intractable clinical problem. The PAVAEX Boot, designed in 1933 by vascular surgeons Louis G. Herrmann and Mont R. Reid, was one of the few interventions for PAD at the time. Based on the observation that continuous negative pressure results in vasoconstriction, while short bursts transiently increase blood flow, the PAVAEX Boot utilized intermittent negative pressure to enhance peripheral vascular perfusion. Well-marketed and praised throughout the 1930s, it vanished from public writing and academic literature just 20 years later. However, negative pressure wound therapy resurged in the late 20th century, and though its inventors failed to recognize the precedent of the PAVAEX Boot, many of these devices and therapies are rooted in identical theories. We examine why the PAVAEX Boot faded from use and argue that the device remains a crucial advancement in negative pressure therapy.
Solid-state
29
Si and
71
Ga NMR was used to study the synthetic gallosilicate Na
16
Ga
16
Si
24
O
80
·16H
2
O (Ga–natrolite). It has been shown that Ga–natrolite contains mainly Si(GaO
4
)
3
(SiO
4
) ...and Si(GaO
4
)
2
(SiO
4
)
2
-structural units and has sufficiently ordered structure. Temperature dependence of the spin–lattice relaxation time
T
1
of
71
Ga nuclei has also been studied using solid-state NMR. Spin–lattice relaxation of the
71
Ga was determined to be governed by the electric quadrupole interaction with the crystal electric field gradients modulated by translational motion of H
2
O molecules in the Ga–natrolite pores.
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