Peroxisomal metabolic machinery requires a continuous flow of organic and inorganic solutes across peroxisomal membrane. Concerning small solutes, the molecular nature of their traffic has remained ...an enigma.
In this study, we show that disruption in mice of the Pxmp2 gene encoding Pxmp2, which belongs to a family of integral membrane proteins with unknown function, leads to partial restriction of peroxisomal membrane permeability to solutes in vitro and in vivo. Multiple-channel recording of liver peroxisomal preparations reveals that the channel-forming components with a conductance of 1.3 nS in 1.0 M KCl were lost in Pxmp2(-/-) mice. The channel-forming properties of Pxmp2 were confirmed with recombinant protein expressed in insect cells and with native Pxmp2 purified from mouse liver. The Pxmp2 channel, with an estimated diameter of 1.4 nm, shows weak cation selectivity and no voltage dependence. The long-lasting open states of the channel indicate its functional role as a protein forming a general diffusion pore in the membrane.
Pxmp2 is the first peroxisomal channel identified, and its existence leads to prediction that the mammalian peroxisomal membrane is permeable to small solutes while transfer of "bulky" metabolites, e.g., cofactors (NAD/H, NADP/H, and CoA) and ATP, requires specific transporters.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Long‐term photometry is commonly used to monitor chromospheric activity of late–type stars. We study standard Johnson differential V photometry of the RS CVn binary BM Canum Venaticorum (BM CVn) ...spanning over a quarter of a century. Our main aims are to determine the activity cycles, the rate of surface differential rotation, and the rotation period of the active longitudes of BM CVn. The continuous period search (CPS) algorithm is applied to the photometry. The changes of the mean and amplitude of the light curves are used to search for activity cycles. The rotation period changes give an estimate of the rate of surface differential rotation. The Kuiper method is applied to the epochs of the primary and secondary minima to search for active longitudes. The photometry reveals the presence of a stable mean light curve (MLC) connected to the orbital period Porb=20.d6252 of this binary. We remove this MLC from the original V magnitudes, which gives us the corrected V′
magnitudes. These two samples of V
and V′
data are analyzed separately with CPS. The fraction of unreliable CPS models decreases when the MLC is removed. The same significant activity cycle of approximately 12.5 years is detected in both V and V′
samples. The estimate for the surface differential rotation coefficient, k⩾0.10, is the same for both samples, but the number of unrealistic period estimates decreases after removing the MLC. The same active longitude period of Pal=20.d511 ± 0.d005 is detected in the V and V′ magnitudes. This long‐term regularity in the epochs of primary and secondary minima of the light curves is not caused by the MLC. On the contrary, the MLC hampers the detection of active longitudes.
Studying RS CVn binaries is challenging, because in addition to spot activity, other effects such as mass transfer between the components and gravitational distortion of their spherical forms may ...distort their light curves. Such effects can, however, be removed from the data by subtracting a mean light curve phased with the orbital period. We study a quarter of a century of standard Johnson differential V photometry of the RS CVn binary BM CVn. Our main aims are to determine the activity cycles, the rate of surface differential rotation and the rotation period of the active longitudes of BM CVn. The Continuous Period Search (CPS) is applied to the photometry. The changes of the mean and amplitude of the light curves are used to search for activity cycles. The rotation period changes give an estimate of the rate of surface differential rotation. The Kuiper method is applied to the epochs of the primary and secondary minima to search for active longitudes. The photometry reveals the presence of a stable mean light curve (MLC) connected to the orbital period P_orb = 20d.6252 of this binary. We remove this MLC from the original V magnitudes which gives us the corrected V' magnitudes. These two samples of V and V' data are analysed separately with CPS. The fraction of unreliable CPS models decreases when the MLC is removed. The same significant activity cycle of approximately 12.5 years is detected in both V and V' samples. The estimate for the surface differential rotation coefficient, k >= 0.10, is the same for both samples, but the number of unrealistic period estimates decreases after removing the MLC. The same active longitude period of P_al = 20d.511 +- 0d.005 is detected in the V and V' magnitudes. This long-term regularity in the epochs of primary and secondary minima of the light curves is not caused by the MLC. On the contrary, the MLC hampers the detection of active longitudes.
An adequate bowel cleansing is essential for a successful colonoscopy. Although purgative consumption is safe for the patient, there is little consensus on how the intestinal microbiota is affected ...by the procedure, especially regarding the potential long-term consequences.
23 healthy subjects were randomised into two study groups consuming a bowel preparation (Moviprep), either in two separate doses of 1 L or as a single 2-L dose. Participants donated faecal samples at the baseline, after bowel cleansing, 14 and 28 days after the treatment. The intestinal microbiota composition was determined with phylogenetic microarray as well as quantitative PCR analysis and correlated with the previously quantified faecal serine proteases.
The lavage introduced an instant and substantial change to the intestinal microbiota. The total microbial load was decreased by 31-fold and 22% of the participants lost the subject-specificity of their microbiota. While the bacterial levels and community composition were essentially restored within 14 days, the rate of recovery was dose dependent: consumption of the purgative in a single dose had a more severe effect on the microbiota composition than that of a double dose, and notably increased the levels of Proteobacteria, Fusobacteria and bacteria related to Dorea formicigenerans. The abundance of the latter also correlated with the amount of faecal serine proteases that were increased after purging.
Our results suggest that the bowel cleansing using two separate dosages introduces fewer alterations to the intestinal microbiota than a single dose and hence may be preferred in clinical practice.
The seed beetle Callosobruchus maculatus is a significant agricultural pest and increasingly studied model of sexual conflict. Males possess genital spines that increase the transfer of seminal fluid ...proteins (SFPs) into the female body. As SFPs alter female behaviour and physiology, they are likely to modulate reproduction and sexual conflict in this species. Here, we identified SFPs using proteomics combined with a de novo transcriptome. A prior 2D‐sodium dodecyl sulphate polyacrylamide gel electrophoresis analysis identified male accessory gland protein spots that were probably transferred to the female at mating. Proteomic analysis of these spots identified 98 proteins, a majority of which were also present within ejaculates collected from females. Standard annotation workflows revealed common functional groups for SFPs, including proteases and metabolic proteins. Transcriptomic analysis found 84 transcripts differentially expressed between the sexes. Notably, genes encoding 15 proteins were highly expressed in male abdomens and only negligibly expressed within females. Most of these sequences corresponded to ‘unknown’ proteins (nine of 15) and may represent rapidly evolving SFPs novel to seed beetles. Our combined analyses highlight 44 proteins for which there is strong evidence that they are SFPs. These results can inform further investigation, to better understand the molecular mechanisms of sexual conflict in seed beetles.
To study 10-year outcomes in patients with early seropositive rheumatoid arthritis (RA) whether the outcomes improve over time.
Data of 1754 patients with early RA, diagnosed in 1997-2011 were ...explored; 66% (n=1151) were seropositive and included in the analyses. Patients were divided into five groups by diagnosis year: 1997-1999, 2000-2002, 2003-2005, 2006-2008 and 2009-2011. Clinical parameters including disease activity and function were compared between the groups.
A total of 832 (72%) patients attended the 10-year visit, while 319 did not (e.g. 196 had died and 49 moved). The median (IQR) DAS28 decreased from 2.9 (2.2, 3.7) to 2.3 (1.4, 3.0) (p<0.001) between groups 1997-1999 and 2009-2011. The proportion of patients with 2 or more swollen joints on 46 joint count decreased from 33% to 13%, respectively. Median (IQR) pain decreased from 30 (15, 52) to 25 (6, 51) (p=0.03) and fatigue from 31 (12, 52) to 15 (2, 50) (p=0.012). Median (IQR) dr.global decreased from 20 (5, 40) to 0 (0, 5) p<0.001. The proportion of patients with a HAQ-score of ≤0.5 increased from 39% to 49% (p=0.002). The proportion of patients that had used methotrexate by the 10-year visit increased from 79% to 96% (p<0.001) and the proportion of patients who had used bDMARDs increased from 11% to 28% (p=0.001), respectively.
Several clinical outcomes were better in patients who were diagnosed more recently. More intensive use of medications over time might have contributed to these improvements.
Low-dose computed tomography tends to produce lower image quality than normal dose computed tomography (CT) although it can help to reduce radiation hazards of CT scanning. Research has shown that ...Artificial Intelligence (AI) technologies, especially deep learning can help enhance the image quality of low-dose CT by denoising images. This scoping review aims to create an overview on how AI technologies, especially deep learning, can be used in dose optimisation for low-dose CT.
Literature searches of ProQuest, PubMed, Cinahl, ScienceDirect, EbscoHost Ebook Collection and Ovid were carried out to find research articles published between the years 2015 and 2020. In addition, manual search was conducted in SweMed+, SwePub, NORA, Taylor & Francis Online and Medic.
Following a systematic search process, the review comprised of 16 articles. Articles were organised according to the effects of the deep learning networks, e.g. image noise reduction, image restoration. Deep learning can be used in multiple ways to facilitate dose optimisation in low-dose CT. Most articles discuss image noise reduction in low-dose CT.
Deep learning can be used in the optimisation of patients’ radiation dose. Nevertheless, the image quality is normally lower in low-dose CT (LDCT) than in regular-dose CT scans because of smaller radiation doses. With the help of deep learning, the image quality can be improved to equate the regular-dose computed tomography image quality.
Lower dose may decrease patients’ radiation risk but may affect the image quality of CT scans. Artificial intelligence technologies can be used to improve image quality in low-dose CT scans. Radiologists and radiographers should have proper education and knowledge about the techniques used.
•Less dose may lower patient radiation risk but may impact image quality of CT scans.•Artificial intelligence technologies can improve image quality in low-dose CT scans.•Different deep learning models have been developed to facilitate dose optimisation in low-dose CT.•Radiologists and radiographers should have proper education and knowledge about the techniques used.
Value co-creation is a core focus area in both B2B marketing and strategy research, necessitating resource utilization within and across organizational boundaries. In the Industrial Marketing and ...Purchasing (IMP) group, scholars have focused on the interactions among resources as one important way to analyze central questions about resources in business relationships and networks. This has produced a breadth of investigations and concepts that are locally defined and utilized. This may hamper further theoretical development and inhibit analytical precision. The purpose of this paper is to develop a more general shared understanding of resource interaction by identifying and explicating the key concepts used, and to assess its status as an approach. The paper synthesizes 20 years of research to identify key concepts and the relationships across concepts. This provides both a platform for further conceptual and empirical research within IMP and potential for cross-fertilization with parallel B2B areas.
•B2B research on resource interaction needs conceptual refinement due to variation and inconsistency in how concepts are used.•We provide an account of a collective process of middle range theorizing of resource interaction.•The purpose is to develop mid-range theory to enhance our understanding of resource interaction.•We synthesize 20 years of research to present 14 key concepts and three representations of connections among concepts.
The male ejaculate contains a multitude of seminal fluid proteins (SFPs), many of which are key reproductive molecules, as well as sperm. However, the identification of SFPs is notoriously difficult ...and a detailed understanding of this complex phenotype has only been achieved in a few model species. We employed a recently developed proteomic method involving whole-organism stable isotope labelling coupled with proteomic and transcriptomic analyses to characterize ejaculate proteins in the seed beetle Callosobruchus maculatus. We identified 317 proteins that were transferred to females at mating, and a great majority of these showed signals of secretion and were highly male-biased in expression in the abdomen. These male-derived proteins were enriched with proteins involved in general metabolic and catabolic processes but also with proteolytic enzymes and proteins involved in protection against oxidative stress. Thirty-seven proteins showed significant homology with SFPs previously identified in other insects. However, no less than 92 C. maculatus ejaculate proteins were entirely novel, receiving no significant blast hits and lacking homologs in extant data bases, consistent with a rapid and divergent evolution of SFPs. We used 3D micro-tomography in conjunction with proteomic methods to identify 5 distinct pairs of male accessory reproductive glands and to show that certain ejaculate proteins were only recovered in certain male glands. Finally, we provide a tentative list of 231 candidate female-derived reproductive proteins, some of which are likely important in ejaculate processing and/or sperm storage.
Display omitted
•Male ejaculate proteins are diverse and rapidly evolving reproductive proteins but their identification is challenging.•We use a proteomic method based on whole-organism stable isotope labelling and tandem mass spectrometry.•We identified 317 male derived proteins, of which 92 are novel proteins, and 231 candidate female reproductive proteins.•3D micro-tomography unveiled 5 distinct pairs of male accessory reproductive glands.•Some proteins were recovered only in some glands, suggesting substantial differentiation across male glands.
Bread is one of the most consumed food products in the world and one of the most discarded, due to its intrinsic short shelf-life and susceptibility to mold spoilage. Additionally, bread waste is ...generated during production and distribution, leading to the disposal of bread otherwise still fit for consumption. To avoid generating huge amount of bread waste, strategies to enable its reutilization should be sought. In this study, surplus bread, still suitable for consumption, was bioprocessed with enzymes and fermented by selected lactic acid bacteria generating an ingredient with antifungal properties. Bread hydrolysate fermented by Lactobacillus brevis AM7 showed broad inhibitory spectrum against the fungal species tested and antifungal activity ranging from 20 to 70%. Nine antifungal peptides were identified via Liquid Chromatography-Electrospray Ionisation-Mass Spectra/Mass Spectra (nano-LC-ESI-MS/MS), having 10–17 amino acid residues and mass ranging from 1083.6 to 1980.7 Da, all of them encrypted in wheat proteins sequences. Bread hydrolysate fermented by Lb. brevis AM7, non-fermented bread hydrolysate and a slurry consisting of water-bread mixture were used as ingredients in bread making and compared to regular wheat bread. Breads containing the fermented hydrolysate (18 and 22% of the dough weight) showed the longest mold-free shelf-life compared to the other breads, lasting up to 10 days before mold appearance. Additionally, the fermented hydrolysate was the least detrimental on bread quality, emphasizing the positive impact and potential of the studied biotechnology.
•Surplus bread was hydrolyzed with enzymes and fermented by LAB.•LAB fermentation increased the antifungal activity of the hydrolyzed bread.•Nine peptides with antifungal properties were identified in the active hydrolysate.•Bread with the active hydrolysate had a shelf-life of 10 days.