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We report the effects of quercetin, a flavonoid present in human diet, on early stage beta-amyloid (Aβ) aggregation – a seminal event in Alzheimer’s disease. Molecular level changes in Aβ arrangements are monitored by time-resolved emission spectral (TRES) measurements of the fluorescence of Aβ’s single tyrosine intrinsic fluorophore (Tyr). The results suggest that quercetin binds beta-amyloid oligomers at early stages of their aggregation, which leads to the formation of modified oligomers and hinders the creation of beta-sheet structures, potentially preventing the onset of Alzheimer’s disease.

Sizzled (Szl) is both a secreted frizzled related protein (sFRP) and a naturally occurring inhibitor of the zinc metalloproteinase bone morphogenetic protein-1 (BMP-1), a key regulator of extracellular matrix assembly and growth factor activation. Here we present a new crystal structure for Szl which differs from that previously reported by a large scale (90°) hinge rotation between its cysteine-rich and netrin-like domains. We also present results of a molecular docking analysis showing interactions likely to be involved in the inhibition of BMP-1 activity by Szl. When compared with known structures of BMP-1 in complex with small molecule inhibitors, this reveals features that may be helpful in the design of new inhibitors to prevent the excessive accumulation of extracellular matrix that is the hallmark of fibrotic diseases.

Plankton ecologists ultimately focus on forecasting, both applied and environmental outcomes. We review how appreciating planktonic ciliates has become central to these predictions. We explore the 350-year-old canon on planktonic ciliates and examine its steady progression, which has been punctuated by conceptual insights and technological breakthroughs. By reflecting on this process, we offer suggestions as to where future leaps are needed, with an emphasis on predicting outcomes of global warming. We conclude that in terms of climate change research: (i) climatic hotspots (e.g. polar oceans) require attention; (ii) simply adding ciliate measurements to zooplankton/phytoplankton-based sampling programs is inappropriate; (iii) elucidating the rare biosphere's functional ecology requires culture-independent genetic methods; (iv) evaluating genetic adaptation (microevolution) and population composition shifts is required; (v) contrasting marine and freshwaters needs attention; (vi) mixotrophy needs attention; (vii) laboratory and field studies must couple automated measurements and molecular assessment of functional gene expression; (viii) ciliate trophic diversity requires appreciation; and (ix) marrying gene expression and function, coupled with climate change scenarios is needed. In short, continued academic efforts and financial support are essential to achieve the above; these will lead to understanding how ciliates will respond to climate change, providing tools for forecasting.

The Ehlers–Danlos syndromes (EDS) are a group of rare inherited connective tissue disorders. Vascular EDS (vEDS) is caused by pathogenic variants in COL3A1, most frequently glycine substitutions. We describe the phenotype of the largest series of vEDS patients with glutamic acid to lysine substitutions (Glu>Lys) in COL3A1, which were all previously considered to be variants of unknown significance. Clinical and molecular data for seven families with three different Glu>Lys substitutions in COL3A1 were analyzed. These Glu>Lys variants were reclassified from variants of unknown significance to either pathogenic or likely pathogenic in accordance with American College of Medical Genetics and Genomics guidelines. All individuals with these atypical variants exhibited skin hyperextensibility as seen in individuals with classical EDS and classical-like EDS and evidence of tissue fragility as seen in individuals with vEDS. The clinical data demonstrate the overlap between the different EDS subtypes and underline the importance of next-generation sequencing gene panel analysis. The three different Glu>Lys variants point toward a new variant type in COL3A1 causative of vEDS, which has consistent clinical features. This is important knowledge for COL3A1 variant interpretation. Further follow-up data are required to establish the severity of tissue fragility complications compared with patients with other recognized molecular causes of vEDS.

Hip pathology is common amongst athletes and the general population. The mechanics of cycling have the potential to exacerbate symptomatic hip pathology and progress articular pathology in patients with morphologic risk factors such as femoroacetabular impingement. A professional fit of the bicycle to the individual which aims to optimize hip joint function can allow patients with hip pathology to exercise in comfort when alternative high impact exercise such as running may not be possible. Conversely improper fit of the bicycle can lead to hip symptoms in otherwise healthy individuals who present with risk factors for hip pain. Accordingly a bike fit can form part of the overall management strategy in a cyclist with hip symptoms. The purpose of this clinical commentary is to discuss hip pathomechanics with respect to cycling, bicycle fitting methodology and the options available to a physical therapist to optimize hip mechanics during the pedaling action.

M13 bacteriophage is a key instrument in phage display applications, as well as a possible antibacterial therapeutic agent due to its highly restrictive bacterial pathogenesis, and other applications. The traditional phage purification process is usually achieved by gradient ultracentrifugation or a combination of precipitation, centrifugation and microfiltration. These approaches easily lead to long process times, high operational costs, phage aggregation and consequent product loss (approximately 60%). This work is thus focused on an alternative potential large-scale process to achieve high yield and purity while minimizing the operational costs. Electrostatic-based separation processes are also common biomolecules purification techniques. Although anion exchange chromatography has been used before to purify several viral particles, this technique has been poorly reported for the purification of M13 phage. In a recent work, our group has demonstrated the use of a predominant anion exchange process, where a polymeric ionic liquid (PIL) was used as an alternative separation matrix for M13 bacteriophage. In this work, a variety of system parameters was studied, including chemical structure of the cation and the anion, the crosslinker nature and its concentration, either in batch adsorption/elution or chromatographic operation mode. The PIL-based chromatographic operation mode revealed to be a suitable separation process for M13 from directly filtered E. coli supernatant, reaching over 70% M13 recovery and 4.6 purification factor in a single step. To our knowledge, this is the first time that PILs have been reported as separation agents for bioproducts from complex mixtures.

The defence collagens C1q and mannose-binding lectin (MBL) are immune recognition proteins that associate with the serine proteinases C1r/C1s and MBL-associated serine proteases (MASPs) to trigger activation of complement, a major innate immune system. Bone morphogenetic protein-1 (BMP-1)/tolloid-like proteinases (BTPs) are metalloproteinases with major roles in extracellular matrix assembly and growth factor signalling. Despite their different functions, C1r/C1s/MASPs and BTPs share structural similarities, including a specific CUB-EGF-CUB domain arrangement found only in these enzymes that mediates interactions with collagen-like proteins, suggesting a possible functional relationship. Here we investigated the potential interactions between the defence collagens C1q and MBL and the BTPs BMP-1 and mammalian tolloid-like-1 (mTLL-1). C1q and MBL bound to immobilized BMP-1 and mTLL-1 with nanomolar affinities. These interactions involved the collagen-like regions of the defence collagens and were inhibited by pre-incubation of C1q or MBL with their cognate complement proteinases. Soluble BMP-1 and mTLL-1 did not inhibit complement activation and the defence collagens were neither substrates nor inhibitors of BMP-1. Finally, C1q co-localized with BMP-1 in skin biopsies following melanoma excision and from patients with recessive dystrophic epidermolysis bullosa. The observed interactions provide support for a functional link between complement and BTPs during inflammation and tissue repair.

A non‐invasive intrinsic fluorescence sensing of the early stages of Alzheimer’s beta amyloid peptide aggregation in the presence of copper ions is reported. By using time‐resolved fluorescence techniques the formation of beta amyloid‐copper complexes and the accelerated peptide aggregation are demonstrated. The shifts in the emission spectral peaks indicate that the peptides exhibit different aggregation pathways than in the absence of copper.

During the last years, poly(ionic liquids) (PILs) have been gaining increased attention as materials for analytical chemistry. This success is due to the fact that PILs synthesis is generally based on the polymerization of ionic liquid monomers (ILMs), and thus some of their remarkable properties are shared with their polymeric form. Consequently, the facile design of task-specific ILMs led to an important platform to design new materials for solid phase microextraction (SPME). In this review, a critical evaluation of the main breakthroughs on the use of PILs as extraction phases for SPME. In particular, this critical review covers from ILMs/PILs synthesis, fiber coating processes, surface modifications (silica and metallic supports), to extraction modes, analytes categories, type of equipment ending with a discussion on limitations and future perspectives. PILs are undoubtedly competing in the frontline as inspiring materials for SPME.

Development of a pseudoaneurysm of the ascending aorta is an uncommon complication of aortic surgery. Several nonsurgical techniques are available for treatment of ascending aortic pseudoaneurysms (AAPs). This report outlines a single-center retrospective experience with 14 nonsurgical procedures for treatment of AAPs in 10 patients. Modified stent grafts, septal defect occlusion devices, coil embolics, and liquid embolics were deployed by transthoracic and endovascular approaches. Complete stasis of the AAP was achieved in 7 of 10 patients (70%). Mean postprocedural recoveries occurred within 3.5 days. Nonsurgical techniques for repair of AAPs offer a comparatively safe and effective alternative to open surgical repair.

Hemangiomas are the most common tumor of the liver and distinguishing them from malignancy is important. This is a report of 3 hemangiomas in 2 patients that exhibit transient washout of gadoxetate disodium (Eovist), relative to blood pool and liver parenchyma, a characteristic that is used to diagnose hepatocellular carcinoma in at-risk patients. It is important to recognize that high-flow hemangiomas can exhibit transient washout when using a small volume of injected contrast agent. This finding is unlikely to be present on CT examinations because of the larger volume of contrast administered.

Familiarity with how MRI sequences can distinguish different tissues when coupled with an understanding of pathology aids in narrowing differentials or making a specific diagnosis. Utilizing specific MRI pulse sequences allows for identification of key tissue substances such as fat, paramagnetic substances, protein, fibrous tissue, or free or bound water. The identification of these tissue substances allows the radiologist to form narrow or specific diagnoses efficiently. A tissue-based approach to understanding MRI sequences allows the radiologist to both systematically and effectively interpret MRIs despite the large number of pulse sequences particularly in basic MRI body protocols.

Mutations in the type I procollagen C-propeptide occur in ~6.5% of Osteogenesis Imperfecta (OI) patients. They are of special interest because this region of procollagen is involved in α chain selection and folding, but is processed prior to fibril assembly and is absent in mature collagen fibrils in tissue. We investigated the consequences of seven COL1A1 C-propeptide mutations for collagen biochemistry in comparison to three probands with classical glycine substitutions in the collagen helix near the C-propeptide and a normal control. Procollagens with C-propeptide defects showed the expected delayed chain incorporation, slow folding and overmodification. Immunofluorescence microscopy indicated that procollagen with C-propeptide defects was mislocalized to the ER lumen, in contrast to the ER membrane localization of normal procollagen and procollagen with helical substitutions. Notably, pericellular processing of procollagen with C-propeptide mutations was defective, with accumulation of pC-collagen and/or reduced production of mature collagen. In vitro cleavage assays with BMP-1 ± PCPE-1 confirmed impaired C-propeptide processing of procollagens containing mutant proα1(I) chains. Overmodified collagens were incorporated into the matrix in culture. Dermal fibrils showed alterations in average diameter and diameter variability and bone fibrils were disorganized. Altered ER-localization and reduced pericellular processing of defective C-propeptides are expected to contribute to abnormal osteoblast differentiation and matrix function, respectively.

In this work, a facile preparation of SPME fibers with increased surface area is presented. The SPME fibers were prepared by grinding poly(ionic liquids) (PILs) to obtain particles of 1–16 µm and, with the aid of a silicon adhesive, attach these particles to a steel wire support. Three different PILs, poly(1-vinyl-3-benzylimidazolium-co-styrene bromide) [poly(ViBnIm-co-Sty Br)], poly(1-vinyl-3-benzylimidazolium-co-styrene bis(trifluoromethanesulfonyl)imide) [poly(ViBnIm-co-Sty TFSI)] and poly(diallyldimethylamine bis(trifluoromethanesulfonyl)imide) [poly(Pyrr11 TFSI)], were used. The first two PILs were obtained by reversible addition–fragmentation chain transfer polymerization followed by metathesis reactions. The thicknesses of the prepared fibers were found to be 19 ± 4 µm and 85% of the particles used have diameters between 2 and 10 µm. The prepared fibers were tested by performing the headspace extraction of two standard solutions, one containing a mixture of alcohols with different chain lengths, and the other a mixture of aromatic compounds, leading to sorption times of 10 – 15 min due the large surface area attained with this method. PILs with aromatic moieties containing the bromide anion showed high selectivity towards polar compounds, due to the hydrogen basicity of the anion, and also towards aromatic analytes, due to the aromatic nature of styrene moieties and the cation pendant groups. The limits of detection fall in the sub ppb level, while relative standard deviations and reproducibility from fiber-to-fiber found maximums of 16.2% and 22.5%, respectively. Furthermore, the PIL based fibers showed up to 90% higher extraction efficiencies compared to the commercial fibers of polydimethylsiloxane and polyacrylate.

Fibrillar collagens of the extracellular matrix are critical for tissue structure and physiology; however, excessive or abnormal deposition of collagens is a defining feature of fibrosis. Regulatory mechanisms that act on collagen fibril assembly potentially offer new targets for antifibrotic treatments. Tissue weakening, altered collagen fibril morphologies, or both, are shared phenotypes of mice lacking matricellular thrombospondins. Thrombospondin-1 (TSP1) plays an indirect role in collagen homeostasis through interactions with matrix metalloproteinases and transforming growth factor–1 (TGF-1). We found that TSP1 also affects collagen fibril formation directly. Compared to skin from wild-type mice, skin from Thbs1-/- mice had reduced collagen cross-linking and reduced prolysyl oxidase (proLOX) abundance with increased conversion to catalytically active LOX. In vitro, TSP1 bound to both the C-propeptide domain of collagen I and the highly conserved KGHR sequences of the collagen triple-helical domain that participate in cross-linking. TSP1 also bound to proLOX and inhibited proLOX processing by bone morphogenetic protein-1. In human dermal fibroblasts (HDFs), TSP1 and collagen I colocalized in intracellular vesicles and on extracellular collagen fibrils, whereas TSP1 and proLOX colocalized only in intracellular vesicles. Inhibition of LOX-mediated collagen cross-linking did not prevent the extracellular association between collagen and TSP1; however, treatment of HDFs with KGHR-containing, TSP1-binding, triple-helical peptides disrupted the collagen-TSP1 association, perturbed the collagen extracellular matrix, and increased myofibroblastic differentiation in a manner that depended on TGF- receptor 1. Thus, the extracellular KGHR-dependent interaction of TSP1 with fibrillar collagens contributes to fibroblast homeostasis.

The design of poly(ionic liquids) (PILs) and their application as solid phase microextraction (SPME) fibers has been attracting enormous attention mainly due to the need for new SPME coating materials with improved analytical sensitivity. In this work, the tunability of PILs is explored by preparing different imidazolium monomers bearing benzyl, naphtylmethyl or pentyl pending groups that were subsequently co-polymerized, by reversible addition–fragmentation chain transfer (RAFT) polymerization with styrene. The obtained co-polymers showed excellent thermal stability up to 275 °C, with no melting point up to 250 °C. SPME fibers were prepared by an innovative approach based on layer-by-layer spray coating. The thin (

Binary systems composed of water and cholinium carboxylate ionic liquids, namely cholinium lactate ([Ch][Lac]), cholinium propanoate ([Ch][Prop]) and cholinium malonate ([Ch][Mal]) were studied from the neat ionic liquid to very diluted aqueous solutions. Densities and viscosities were measured and atypical behaviors were observed, such as the increasing density of the binary [Ch][Prop] + H2O mixtures with increasing water content. In order to get molecular level insights on the IL + H2O solvation schemes, 1H NMR studies were performed. Large deviations were obtained in the anions resonances when compared to those of the cation suggesting that water interacts preferentially with the anion counter-part of the ionic liquid. The increasing density of [Ch][Prop] + H2O system with increasing water content can be related to the orientation of the alkyl chains, as a result of their nanoscale organization. This behavior was confirmed through the study of the thermophysical properties of [Ch][Hex] + H2O mixtures, where this phenomenon is known to occur.

Crosslinked pyrrolidinium-based poly(ionic liquids) (Pyrr-PILs) were synthesized through a fast, simple, and solventless photopolymerization scheme, and tested as solid phase microextraction (SPME) sorbents. A series of Pyrr-PILs bearing three different alkyl side chain lengths with two, eight, and fourteen carbons was prepared, characterized, and homogeneously coated on a steel wire by using a very simple procedure. The resulting coatings showed a high thermal stability, with decomposition temperatures above 350 degrees C, excellent film stability, and lifetime of over 100 injections. The performance of these PIL-based SPME fibers was evaluated using a mixture of eleven organic compounds with different molar volumes and chemical functionalities (alcohols, ketones, and monoterpenes). The Pyrr-PIL fibers were obtained as dense film coatings, with 67 mu m thickness, with an overall sorption increase of 90% and 55% as compared to commercial fibers of Polyacrylate (85 mu m) (PA85) and Polydimethylsiloxane (7 mu m) (PDMS7) coatings, respectively. A urine sample doped with the sample mixture was used to study the matrix effect and establish relative recoveries, which ranged from 60.2% to 104.1%. David J. S. Patinha, and Liliana C. Tome are grateful to FCT (Fundacao para a Ciencia e a Tecnologia) for the PhD research grant SFRH/BD/97042/2013 and the Post-Doctoral research grant (SFRH/BPD/101793/2014), respectively. David J. S. Patinha also thanks the financial support from COST-Exil Project 1206. The NMR data was acquired at CERMAX (Centro de Ressonncia Magnetica Antnio Xavier) which is a member of the National NMR network. This work was partially supported by FCT through Research Unit GREEN-it " Bioresources for Sustainability" (UID/Multi/04551/2013) and the Associate Laboratory CICECO Aveiro Institute of materials (UID/CTM/50011/2013).

The C propeptides of fibrillar procollagens have crucial roles in tissue growth and repair by controlling both the intracellular assembly of procollagen molecules and the extracellular assembly of collagen fibrils. Mutations in C propeptides are associated with several, often lethal, genetic disorders affecting bone, cartilage, blood vessels and skin. Here we report the crystal structure of a C-propeptide domain from human procollagen III. It reveals an exquisite structural mechanism of chain recognition during intracellular trimerization of the procollagen molecule. It also gives insights into why some types of collagen consist of three identical polypeptide chains, whereas others do not. Finally, the data show striking correlations between the sites of numerous disease-related mutations in different C-propeptide domains and the degree of phenotype severity. The results have broad implications for understanding genetic disorders of connective tissues and designing new therapeutic strategies.