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Stemness and pluripotency are mediated by transcriptional master regulators that promote self-renewal and repress cell differentiation, among which is the high-mobility group (HMG) box transcription factor SOX2. Dysregulated SOX2 expression, by contrast, leads to transcriptional aberrations relevant to oncogenic transformation, cancer progression, metastasis, therapy resistance, and relapse. Here, we report a post-transcriptional mechanism by which the cytosolic pool of SOX2 contributes to these events in an unsuspected manner. Specifically, a low-complexity region within SOX2's C-terminal segment connects to the ribosome to modulate the expression of cognate downstream factors. Independent of nuclear structures or DNA, this C-terminal functionality alone changes metabolic properties and induces non-adhesive growth when expressed in the cytosol of SOX2 knockout cells. We thus propose a revised model of SOX2 action where nuclear and cytosolic fractions cooperate to impose cell fate decisions via both transcriptional and translational mechanisms. [Display omitted] • The pluripotency-inducing transcription factor SOX2 interacts with ribosomes • SOX2 modulates translation independent of nuclear structures or DNA • Extra-nuclear SOX2 autonomously induces clonogenicity and 3D growth • This redefines SOX2 as a transcriptional and translational regulator of cell fate SOX2 is a gene regulator and world-famous for its importance for stem cells. Based on observations in cancer cells, Schaefer et al. now propose a revised understanding of SOX2 action where gene regulation in the nucleus and protein synthesis in association with cytosolic ribosomes jointly regulate cell fate. [ABSTRACT FROM AUTHOR]

Objective: To determine the effectiveness of TENS at relieving pain and improving physical function as compared to placebo TENS, and to determine its safety, in patients with knee osteoarthritis.Methods: Multi-centre, parallel, 1:1 randomized, double-blind, placebo-controlled clinical trial conducted in six outpatient clinics in Switzerland. We included 220 participants with knee osteoarthritis recruited between October 15, 2012, and October 15, 2014. Patients were randomized to 3 weeks of treatment with TENS (n = 108) or placebo TENS (n = 112). Our pre-specified primary endpoint was knee pain at the end of 3-weeks treatment assessed with the WOMAC pain subscale. Secondary outcome measures included WOMAC physical function subscale and safety outcomes.Results: There was no difference between TENS and placebo TENS in WOMAC pain at the end of treatment (mean difference -0.06; 95%CI -0.41 to 0.29; P = 0.74), nor throughout the trial duration (P = 0.98). Subgroup analyses did not indicate an interaction between patient/treatment characteristics and treatment effect on WOMAC pain at the end of treatment (P-interaction ≥0.22). The occurrence of adverse events was similar across groups, with 10.4% and 10.6% of patients reporting events in the TENS and placebo TENS groups, respectively (P = 0.95). No relevant differences were observed in secondary outcomes.Conclusions: TENS does not improve knee osteoarthritis pain when compared to placebo TENS. Therapists should consider other potentially more effective treatment modalities to decrease knee osteoarthritis pain and facilitate strengthening and aerobic exercise. Our findings are conclusive and further trials comparing TENS and placebo TENS in this patient population are not necessary. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is the most common cause of bacterial skin infections in humans, including patients with atopic dermatitis (AD). Polymorphonuclear neutrophils (PMNs) are the first cells to infiltrate an infection site, where they usually provide an effective first line of defense, including neutrophil extracellular trap (NET) formation. Here, we show that infiltrating PMNs in inflamed human and mouse skin enhance S. aureus skin colonization and persistence. Mechanistically, we demonstrate that a crosstalk between keratinocytes and PMNs results in enhanced NET formation upon S. aureus infection, which in turn induces oxidative stress and expression of danger-associated molecular patterns such as high-mobility-group-protein B1 (HMGB1) in keratinocytes. In turn, HMGB1 enhances S. aureus skin colonization and persistence by promoting skin barrier dysfunctions by the downregulation of epidermal barrier genes. Using patient material, we show that patients with AD exhibit enhanced presence of PMNs, NETs, and HMGB1 in the skin, demonstrating the clinical relevance of our finding. [Display omitted] • Crosstalk with keratinocytes primes neutrophils for NET formation upon S. aureus infection • Enhanced presence of neutrophils and NETs induces oxidative stress in the skin • NETs induce ROS-mediated secretion of HMGB1 by keratinocytes • NETs and extracellular HMGB1 downregulate epidermal barrier genes Focken et al. show that in inflamed skin, the enhanced presence of neutrophils and NETs induces ROS-mediated secretion of HMGB1, which in turn mediates the downregulation of epidermal barrier genes, thus driving S. aureus skin colonization. [ABSTRACT FROM AUTHOR]

The binding of titanocene to DNA and RNA was examined by means of electrospray mass spectrometry. Titanocene served as a model for its therapeutically active derivatives. The binding preferences were probed by competition experiments with oligonucleotides of varying nucleobase compositions and sequences. Results from competition experiments revealed a generally increased preference for the binding to phosphate groups adjacent to thymidines, which is affected by the nucleobase sequence of T-rich oligonucleotides. More detailed information about the binding sites was obtained from tandem mass spectrometric experiments. The binding of the transition metal coordination center significantly altered the fragment ion patterns of the oligonucleotides. RNA was found to be less prone to adduct formation, due to intramolecular interactions. The findings from experiments on DNA and RNA were complemented by the examination of backbone- and ribose-modified oligonucleotides. [ABSTRACT FROM AUTHOR]

Background Whole genome sequence (WGS)-based strain typing finds increasing use in the epidemiologic analysis of bacterial pathogens in both public health as well as more localized infection control settings. Aims This minireview describes methodologic approaches that have been explored for WGS-based epidemiologic analysis and considers the challenges and pitfalls of data interpretation. Sources Personal collection of relevant publications. Content When applying WGS to study the molecular epidemiology of bacterial pathogens, genomic variability between strains is translated into measures of distance by determining single nucleotide polymorphisms in core genome alignments or by indexing allelic variation in hundreds to thousands of core genes, assigning types to unique allelic profiles. Interpreting isolate relatedness from these distances is highly organism specific, and attempts to establish species-specific cutoffs are unlikely to be generally applicable. In cases where single nucleotide polymorphism or core gene typing do not provide the resolution necessary for accurate assessment of the epidemiology of bacterial pathogens, inclusion of accessory gene or plasmid sequences may provide the additional required discrimination. Implications As with all epidemiologic analysis, realizing the full potential of the revolutionary advances in WGS-based approaches requires understanding and dealing with issues related to the fundamental steps of data generation and interpretation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A room-temperature, 3D microprinting process is introduced that produces void-free gold microstructures using localized electrodeposition and cyanide-free chemistry. • The vertical printing rate of the gold is controlled using the electrodeposition potential and goes up to 1.2 µm s−1. • The printing throughput of the gold is controlled using air pressure and reaches up to 20 µm3s−1. • The as-deposited resistivity of the gold is 2.5 times higher than bulk and that of the copper only 10 % higher than bulk. Directly 3D-printed metal microstructures could enable hybrid micromanufacturing, combining conventional micromanufacturing with additive micromanufacturing (µAM). The microstructure's material properties, including the electrical resistivity, are of decisive importance for a wide range of applications in microelectronics, high-frequency communication, and biomedical engineering. In this work, we present a room-temperature process for µAM of gold structures based on local electrodeposition. We demonstrate control of the electrodeposition process by regulating the precursor species supply rate through air pressure and by regulating the reaction rate through the electrodeposition potential. We 3D printed complex gold microscale structures and characterized the resistivity of the printed gold by developing hybrid devices with integrated four-point probe measurement capability. Additionally, we printed copper microwires, building on a previously shown copper µAM process, and characterized the copper resistivity. We demonstrate near-bulk resistivity values of 65 nΩ·m (about 2.5 times higher than bulk) and 19 nΩ·m (only 10% higher than bulk) for the gold and copper wires, respectively, without post-treatment. Microstructural analysis of the gold wires revealed a dense metal deposit free of voids. Finally, we printed gold structures on a pre-patterned substrate, paving the way to hybrid devices in which additive micromanufacturing is combined with existing micromanufacturing techniques. [ABSTRACT FROM AUTHOR]

Calreticulin (CALR) is an endoplasmic reticulum (ER)-retained chaperone that assists glycoproteins in obtaining their structure. CALR mutations occur in patients with myeloproliferative neoplasms (MPNs), and the ER retention of CALR mutants (CALR MUT) is reduced due to a lacking KDEL sequence. Here, we investigate the impact of CALR mutations on protein structure and protein levels in MPNs by subjecting primary patient samples and CALR -mutated cell lines to limited proteolysis-coupled mass spectrometry (LiP-MS). Especially glycoproteins are differentially expressed and undergo profound structural alterations in granulocytes and cell lines with homozygous, but not with heterozygous, CALR mutations. Furthermore, homozygous CALR mutations and loss of CALR equally perturb glycoprotein integrity, suggesting that loss-of-function attributes of mutated CALR chaperones (CALR MUT) lead to glycoprotein maturation defects. Finally, by investigating the misfolding of the CALR glycoprotein client myeloperoxidase (MPO), we provide molecular proof of protein misfolding in the presence of homozygous CALR mutations. [Display omitted] • Proteolysis-coupled mass spectrometry analysis of myeloproliferative neoplasms • Homozygous CALR mutations perturb the structural landscape of the glycoproteome • CALR mutations lead to a chaperone defect and misfolding of myeloperoxidase • Both the holdase and foldase functions are affected by CALR mutations Schürch et al. apply limited proteolysis-coupled mass spectrometry to assess structural perturbations of the proteome in myeloproliferative neoplasms (MPNs) with mutations in the endoplasmic reticulum chaperone calreticulin. They show that calreticulin mutations perturb the structural landscape of the glycoproteome and provide molecular proof of protein misfolding in calreticulin -mutated MPNs. [ABSTRACT FROM AUTHOR]

Abstract: Medical literature regularly reports on accidental poisoning in children after aspiration of combustibles such as lamp oils which usually contain hydrocarbons or rape methyl esters (RMEs). We aimed to analyze the toxic potential of alkanes and different combustible classes in vitro with regard to biologic responses and mechanisms mediating toxicity. Two different in vitro models were used, i.e. (i) a captive bubble surfactometer (CBS) to assess direct influence of combustibles on biophysical properties of surfactant film and (ii) cell cultures (BEAS-2B and R3/1 cells, primary macrophages, re-differentiated epithelia) closely mimicking the inner lung surface. Biological endpoints included cell viability, cytotoxicity and inflammatory mediator release. CBS measurements demonstrate that combustibles affect film dynamics, i.e. the surface tension/area characteristics during compression and expansion, in a dose and molecular chain length dependent manner. Cell culture results confirm the dose dependent toxicity. Generally, cytotoxicity and cytokine release are higher in short-chained alkanes and hydrocarbon-based combustibles than in long-chained substances, e.g. highest inducible cytotoxicity in BEAS-2B was for hexane 84.6%, decane 74% and hexadecane 30.8%. Effects of RME-based combustibles differed between the cell models. Our results confirm data from animal experiments and give new insights into the mechanisms underlying the adverse health effects observed. [Copyright &y& Elsevier]

Abstract: Based on a single-case observation, the descriptive label “leiomyomatoid angiomatous neuroendocrine tumor” (LANT) has been tentatively applied to what was perceived as a possible novel type of dual-lineage pituitary neoplasm with biphasic architecture. We report on two additional examples of an analogous phenomenon encountered in male patients, aged 59 years (Case 1) and 91 years (Case 2). Both tumors were intra- and suprasellar masses, measuring 5.6cm×4.4cm×3.4cm, and 2.7cm×2cm×1.7cm, respectively. Histologically, Case 1 was an FSH-cell adenoma interwoven by vascularized connective tissue septa that tended to exhibit incremental stages of adventitial overgrowth. The epithelial component of Case 2 corresponded to an LH-cell adenoma, and lay partitioned by a maze of paucicellular to hyalinized vascular axes. Irrespective of architectural variations, perivascular spindle cells exhibited immunopositivity for vimentin, muscular actin, and smooth muscle actin. Conversely, negative results were obtained for CD34, EMA, S100 protein, GFAP, and TTF-1. Ultrastructural study failed to reveal metaplastic cell forms involving transitional features between adenohypophyseal–epithelial and mesenchymal–contractile phenotype. We propose that LANT be regarded as a peculiar reflection of maladaptive angiogenesis in some pituitary adenomas, rather than a genuine hybrid neoplasm. While no mechanistic clue is forthcoming to account for this distinctive pattern, hemodynamic strain through direct arterial – rather than portal – supply of the adenoma''s capillary bed may be one such explanatory factor. The apparent predilection of the LANT pattern for macroadenomas of the gonadotroph cell lineage remains unexplained. [Copyright &y& Elsevier]

Abstract: Mycobacterium bovis isolates from the Iberian Peninsula are dominated by strains with spoligotype patterns deleted for spacer 21. Whole-genome sequencing of three Spanish strains with spacer 21 missing in their spoligotype pattern revealed a series of SNPs and subsequent screening of a selection of these SNPs identified one in gene guaA that is specific to these strains. This group of strains from the Iberian Peninsula missing spoligotype spacer 21 represents a new clonal complex of M. bovis, defined by the SNP profile with a distinct spoligotype signature. We have named this clonal complex European 2 (Eu2) and found that it was present at low frequency in both France and Italy and absent from the British Isles. [Copyright &y& Elsevier]

Abstract: Current typing methods for Mycobacterium tuberculosis complex evolved from simple phenotypic approaches like phage typing and drug susceptibility profiling to DNA-based strain typing methods, such as IS6110-restriction fragment length polymorphisms (RFLP) and variable number of tandem repeats (VNTR) typing. Examples of the usefulness of molecular typing are source case finding and epidemiological linkage of tuberculosis (TB) cases, international transmission of MDR/XDR-TB, the discrimination between endogenous reactivation and exogenous re-infection as a cause of relapses after curative treatment of tuberculosis, the evidence of multiple M. tuberculosis infections, and the disclosure of laboratory cross-contaminations. Simultaneously, phylogenetic analyses were developed based on single nucleotide polymorphisms (SNPs), genomic deletions usually referred to as regions of difference (RDs) and spoligotyping which served both strain typing and phylogenetic analysis. National and international initiatives that rely on the application of these typing methods have brought significant insight into the molecular epidemiology of tuberculosis. However, current DNA fingerprinting methods have important limitations. They can often not distinguish between genetically closely related strains and the turn-over of these markers is variable. Moreover, the suitability of most DNA typing methods for phylogenetic reconstruction is limited as they show a high propensity of convergent evolution or misinfer genetic distances. In order to fully explore the possibilities of genotyping in the molecular epidemiology of tuberculosis and to study the phylogeny of the causative bacteria reliably, the application of whole-genome sequencing (WGS) analysis for all M. tuberculosis isolates is the optimal, although currently still a costly solution. In the last years WGS for typing of pathogens has been explored and yielded important additional information on strain diversity in comparison to the classical DNA typing methods. With the ongoing cost reduction of DNA sequencing it is possible that WGS will become the sole diagnostic tool in the secondary laboratory diagnosis of tuberculosis for identification, drug susceptibility testing and genetic characterization. [Copyright &y& Elsevier]

Abstract: The Beijing genotype family is an epidemiologically important sub-group of Mycobacterium tuberculosis. It has been suggested that the high frequency of the Beijing isolates in some areas could be explained by selective advantages. Some evidence suggests that the emerging and most frequently isolated “Typical Beijing” lineage has the ability to circumvent BCG-induced immunity. To investigate the phylogeny of the Beijing genotype of M. tuberculosis, the genome of six Beijing strains from three different countries was sequenced with next-generation sequencing. The phylogeny of these strains was established using single nucleotide polymorphisms (SNPs). The three Typical Beijing strains clustered very tightly in the Beijing phylogeny suggesting that Typical Beijing strains represent a monophyletic lineage and resulted from recent diversification. Typing of 150 M. tuberculosis strains with a subset of the SNPs and comparison of the IS6110 restriction-fragment length polymorphism (RFLP) patterns of these strains to a database of 1522 Beijing RFLP patterns revealed that about 80% of all Beijing strains belong to the Typical Beijing subclone, which indicates clonal expansion. To identify the genomic changes that are characteristic for all Typical Beijing strains and to reconstruct their most recent common ancestor, the presence of SNPs was assayed in other Beijing strains. We identified 51 SNPs that define the minimal set of polymorphisms for all Typical Beijing strains. Nonsynonymous polymorphisms in genes coding for the regulatory network were over-represented in this set of mutations. We suggest that alterations in the response to environmental signals may have enabled Typical Beijing strains to develop the emerging phenotype. [Copyright &y& Elsevier]

Abstract: In the everyday routine of an analytic lab, one is often confronted with the challenge to identify an unknown microbial sample lacking prior information to set the search limits. In the present work, we propose a workflow, which uses the spectral diversity of a commercial database (SARAMIS) to narrow down the search field at a certain taxonomic level, followed by a refined classification by supervised modelling. As supervised learning algorithm, we have chosen a shrinkage discriminant analysis approach, which takes collinearity of the data into account and provides a scoring system for biomarker ranking. This ranking can be used to tailor specific biomarker subsets, which optimize discrimination between subgroups, allowing a weighting of misclassification. The suitability of the approach was verified based on a dataset containing the mass spectra of three Yersinia species Yersinia enterocolitica, Y. pseudotuberculosis and Yersinia pestis. Thereby, we laid the emphasis on the discrimination between the highly related species Yersinia pseudotuberculosis and Y. pestis. All three species were correctly identified at the genus level by the commercial database. Whereas Y. enterocolitica was correctly identified at the species level, discrimination between the highly related Y. pseudotuberculosis and Y. pestis strains was ambiguous. With the use of the supervised modelling approach, we were able to accurately discriminate all the species even when grown under different culture conditions. [Copyright &y& Elsevier]

Abstract: A total of six polymorphisms were identified by comparing the genomes of the first and the last isolate of a well-characterized transmission chain of Mycobacterium tuberculosis involving five patients over a 12 and a half year period. The six polymorphisms consisted of four single nucleotide changes (SNPs), a tandem repeat polymorphism (TRP) and a previously identified IS6110 transposition event. These polymorphic sites were surveyed in each of the isolates from the five patients in the transmission chain. Surprisingly, five of the six polymorphisms accumulated in a single patient in the transmission chain; this patient had been non-compliant to tuberculosis treatment. This first insight into the tempo and mode of molecular evolution in M. tuberculosis at the patient-to-patient level suggests that the molecular evolution of the pathogen in vivo is characterized by periods of relative genomic stability followed by bursts of mutation. Whatever the mechanism for the accumulation of mutations, this observation may have profound consequences for the application of vaccines and therapeutic drugs, the management and treatment of disease outbreaks of M. tuberculosis, the most important bacterial pathogen of humans. [Copyright &y& Elsevier]

Summary: Complications and failures after microvascular free tissue transfer for lower extremity reconstruction have a negative impact on postoperative course and final outcome. Therefore, a 10-year analysis on lower extremity reconstruction with free flaps was performed with a special emphasis on patient co-morbidities such as cardiovascular diseases, diabetes mellitus, body mass index and history of smoking, in order to identify potential risk factors. Complications such as haematoma, seroma, infection, wound dehiscence, as well as partial flap loss, postoperative thrombosis of the anastomosis and eventual total flap loss were gathered from the medical records. Limb salvage was 100%, however 40% suffered from complications ranging from minor wound dehiscence to total flap loss. None of the above-mentioned potential risk factors was associated with an increased rate of complications. However, in flaps that required revision for thrombosis, the age of the patients was significantly higher in the group of flaps that eventually failed when compared to flaps that were salvaged. In conclusion, lower extremity reconstruction with microvascular free tissue transfer is a safe and reliable procedure with a high success rate, however partial flap loss remains an important issue. Increased age was the only factor identified with an increased risk for subsequent flap loss in cases that were revised for thrombosis. [Copyright &y& Elsevier]

Abstract: A molecular film of pulmonary surfactant strongly reduces the surface tension of the lung epithelium–air interface. Human pulmonary surfactant contains 5–10% cholesterol by mass, among other lipids and surfactant specific proteins. An elevated proportion of cholesterol is found in surfactant, recovered from acutely injured lungs (ALI). The functional role of cholesterol in pulmonary surfactant has remained controversial. Cholesterol is excluded from most pulmonary surfactant replacement formulations, used clinically to treat conditions of surfactant deficiency. This is because cholesterol has been shown in vitro to impair the surface activity of surfactant even at a physiological level. In the current study, the functional role of cholesterol has been re-evaluated using an improved method of evaluating surface activity in vitro, the captive bubble surfactometer (CBS). Cholesterol was added to one of the clinically used therapeutic surfactants, BLES, a bovine lipid extract surfactant, and the surface activity evaluated, including the adsorption rate of the substance to the air–water interface, its ability to produce a surface tension close to zero and the area compression needed to obtain that low surface tension. No differences in the surface activity were found for BLES samples containing either none, 5 or 10% cholesterol by mass with respect to the minimal surface tension. Our findings therefore suggest that the earlier-described deleterious effects of physiological amounts of cholesterol are related to the experimental methodology. However, at 20%, cholesterol effectively abolished surfactant function and a surface tension below 15 mN/m was not obtained. Inhibition of surface activity by cholesterol may therefore partially or fully explain the impaired lung function in the case of ALI. We discuss a molecular mechanism that could explain why cholesterol does not prevent low surface tension of surfactant films at physiological levels but abolishes surfactant function at higher levels. [Copyright &y& Elsevier]

The primary function of pulmonary surfactant is to reduce the surface tension (ST) created at the air–liquid interface in the lung. Surfactant is a complex mixture of lipids and proteins and its function is influenced by physiological parameters such as metabolic rate, body temperature and breathing. In the microchiropteran bat Chalinolobus gouldii these parameters fluctuate throughout a 24 h period. Here we examine the surface activity of surfactant from warm–active and torpid bats at both 24°C and 37°C to establish whether alterations in surfactant composition correlate with changes in surface activity. Bats were housed in a specially constructed bat room at Adelaide University, at 24°C and on a 8:16 h light:dark cycle. Surfactant was collected from bats sampled during torpor (2535°C). Alterations in the lipid composition of surfactant occur with changes in the activity cycle. Most notable is an increase in surfactant cholesterol (Chol) with decreases in body temperature [Codd et al., Physiol. Biochem. Zool. 73 (2000) 605–612]. Surfactant from active bats was more surface active at higher temperatures, indicated by lower STmin and less film area compression required to reach STmin at 37°C than at 24°C. Conversely, surfactant from torpid bats was more active at lower temperatures, indicated by lower STmin and less area compression required to reach STmin at 24°C than at 37°C. Alterations in the Chol content of bat surfactant appear to be crucial to allow it to achieve low STs during torpor. [Copyright &y& Elsevier]

During the last 50 years, the perception of nutrition variables that affect behavioral development has shifted, as have the scientific hypotheses that were addressed, the design of the studies that were conducted, the nature and composition of the dietary supplements that were given and compared and the interpretation of outcomes. Methods of diagnosing malnutrition and identifying the populations at risk of becoming malnourished are reviewed in relation to nutrition interventions. Even in dietary supplementation studies it can be difficult to isolate specific nutrient effects because of associations and interactions among dietary components. These and other problems associated with the study of possible effects of dietary energy, protein and micronutrients, and of breast vs. formula feeding on human development are examined. Where dietary intake data, biochemical indicators or clinical symptoms strongly suggest that presence of a single nutrient deficiency, the appropriate action may continue to be food supplementation or fortification, until the corresponding nutrient deficiency has been rectified in the habitual diet; where the nature of the deficiency is less clear, supplementation trials and programs aimed at improving dietary diversity and quality in general are more likely to show effects on indicators of behavioral development. [ABSTRACT FROM AUTHOR]

Tandem mass spectrometry has found widespread application as a powerful tool for the characterization of linear and branched oligosaccharides. Though the technique has been applied to the analysis of cyclic oligosaccharides as well, the underlying fragmentation mechanisms have hardly been investigated. This study focuses on the mechanistic aspects of the gas-phase dissociation of protonated β-cyclodextrins. Elucidation of the dissociation mechanisms is supported by tandem mass spectrometric experiments and by experiments on di- and trimethylated cyclodextrin derivatives. The fragmentation pathway comprises the linearization of the macrocyclic structure as the initial step of the decomposition, followed by the elimination of glucose subunits and the subsequent release of water and formaldehyde moieties from the glucose monomer and dimer fragment ions. Linearization of the macrocycle occurs due to proton-driven scission of the glycosidic bond adjacent to carbon atom C1 in conjunction with the formation of a new hydroxy group. The resulting ring-opened structure further decomposes in charge-independent processes forming either zwitterionic fragments, a 1,4-anhydroglucose moiety, or a new macrocyclic structure, that is lost as a neutral, and an oxonium ion. Since the hydroxy group formed at the ring-opening site can be regarded as the non-reducing end of the linearized structure, the fragment ion nomenclature commonly used for linear and branched oligosaccharides, which relies on the designation of a reducing and a non-reducing end, can also be applied to the description of fragment ions derived from cyclic structures. [Display omitted] • Gas-phase dissociation mechanisms of protonated β-cyclodextrins are elucidated. • Linearization of the macrocyclic structure is the initial fragmentation step. • Neutral loss of subunits follows hitherto unresolved charge-independent mechanisms. • Methylated cyclodextrin analysis supports elucidation of dissociation mechanism. [ABSTRACT FROM AUTHOR]

Self-renewal is a key characteristic of leukemia stem cells (LSCs) responsible for the development and maintenance of leukemia. In this study, we identify CD93 as an important regulator of self-renewal and proliferation of murine and human LSCs, but not hematopoietic stem cells (HSCs). The intracellular domain of CD93 promotes gene transcription via the transcriptional regulator SCY1-like pseudokinase 1 independently of ligation of the extracellular domain. In a drug library screen, we identify the anti-emetic agent metoclopramide as an efficient blocker of CD93 signaling. Metoclopramide treatment reduces murine and human LSCs in vitro and prolongs survival of chronic myeloid leukemia (CML) mice through downregulation of pathways related to stemness and proliferation in LSCs. Overall, these results identify CD93 signaling as an LSC-specific regulator of self-renewal and proliferation and a targetable pathway to eliminate LSCs in CML. • CD93 is a marker for leukemia stem cells (LSCs) in CML • The intracellular domain of CD93 promotes stemness and self-renewal of CML LSCs • The anti-emetic drug metoclopramide blocks CD93 signaling in LSCs CD93 is a marker for LSCs in CML, but its broad expression on normal tissue hinders the development of CD93-targeting therapies. Riether et al. show that signaling via the intracellular domain of CD93 selectively promotes self-renewal of LSCs and that this process can be inhibited with the anti-emetic drug metoclopramide. [ABSTRACT FROM AUTHOR]

Gaussian Processes (GPs) are powerful kernelized methods for non-parametric regression used in many applications. However, their use is limited to a few thousand of training samples due to their cubic time complexity. In order to scale GPs to larger datasets, several sparse approximations based on so-called inducing points have been proposed in the literature. In this work we investigate the connection between a general class of sparse inducing point GP regression methods and Bayesian recursive estimation which enables Kalman Filter like updating for online learning. The majority of previous work has focused on the batch setting, in particular for learning the model parameters and the position of the inducing points, here instead we focus on training with mini-batches. By exploiting the Kalman filter formulation, we propose a novel approach that estimates such parameters by recursively propagating the analytical gradients of the posterior over mini-batches of the data. Compared to state of the art methods, our method keeps analytic updates for the mean and covariance of the posterior, thus reducing drastically the size of the optimization problem. We show that our method achieves faster convergence and superior performance compared to state of the art sequential Gaussian Process regression on synthetic GP as well as real-world data with up to a million of data samples. [ABSTRACT FROM AUTHOR]

Serum acetate increases upon systemic infection. Acutely, assimilation of acetate expands the capacity of memory CD8+ T cells to produce IFN-γ. Whether acetate modulates memory CD8+ T cell metabolism and function during pathogen re-encounter remains unexplored. Here we show that at sites of infection, high acetate concentrations are being reached, yet memory CD8+ T cells shut down the acetate assimilating enzymes ACSS1 and ACSS2. Acetate, being thus largely excluded from incorporation into cellular metabolic pathways, now had different effects, namely (1) directly activating glutaminase, thereby augmenting glutaminolysis, cellular respiration, and survival, and (2) suppressing TCR-triggered calcium flux, and consequently cell activation and effector cell function. In vivo , high acetate abundance at sites of infection improved pathogen clearance while reducing immunopathology. This indicates that, during different stages of the immune response, the same metabolite—acetate—induces distinct immunometabolic programs within the same cell type. • Acetate concentrations are increased at sites of inflammation • TCR signaling and acetate reduce ACSS1/2 expression in memory CD8+ T cells • Glutaminolysis is boosted and calcium flux inhibited by acetate • Local acetate accumulation protects from immunopathology Balmer et al. uncover that acetate abundance steadily increases at sites of inflammation. Acetate directly affects the activation and function of memory CD8+ T cells by activating glutaminolysis and reducing calcium availability. In vivo , the integrated pro- and anti-inflammatory activities of acetate balance immune control with immunopathology. [ABSTRACT FROM AUTHOR]

• Damaging infestations of Lygus lineolaris in Virginia cotton relate to biotic and abiotic factors. • Higher minimum temperatures are associated with increased L. lineolaris infestations. • Crop production area and forest disturbance drive L. lineolaris infestations detected in cotton. Lygus lineolaris populations have become increasingly problematic in Virginia cotton since 2013. Although production practices have changed, changes in landscape composition and climatic conditions are also anecdotally associated with increasing populations. To better understand the recent increase in L. lineolaris infestations in Virginia cotton, 56 commercial cotton fields were sampled weekly in 2017 and 2018 for a nine-week period during the growing season. Insect density was measured using sweep net and black drop cloth sampling, targeting adult and nymphal populations, respectively. Geospatial crop production and forest disturbance data were used to measure the composition and management history of landscapes adjacent to sample fields. We also used spatial climate data sets to document the relationship between increasing L. lineolaris and temperature variation. We investigated the significance of landscape composition and climatic effects increasing L. lineolaris infestation intensity using a regression modeling approach. We found the best overall predictor of L. lineolaris abundance was higher annual minimum temperatures. Several crop components in the landscape were significant, specifically corn and double-crop winter wheat and soybeans, but these habitat patches did not explain high levels of variability. Results of this study suggest that increasing minimum temperatures will favor L. lineolaris and may translate into elevated infestation intensity and increasing dependence on insecticide inputs to manage this problematic pest of cotton. Results of this study will be important to describe short- and long-term factors driving L. lineolaris infestation risk in cotton agroecosystems. [ABSTRACT FROM AUTHOR]

Spider venom neurotoxins and cytolytic peptides are expressed as elongated precursor peptides, which are post-translationally processed by proteases to yield the active mature peptides. The recognition motifs for these processing proteases, first published more than 10 years ago, include the processing quadruplet motif (PQM) and the inverted processing quadruplet motif (iPQM). However, the identification of the relevant proteases was still pending. Here we describe the purification of a neurotoxin precursor processing protease from the venom of the spider Cupiennius salei. The chymotrypsin-like serine protease is a 28-kDa heterodimer with optimum activity at venom's pH of 6.0. We designed multiple synthetic peptides mimicking the predicted cleavage sites of neurotoxin precursors. Using these peptides as substrates, we confirm the biochemical activity of the protease in propeptide removal from neurotoxin precursors by cleavage C-terminal of thePQM.Furthermore, thePQMprotease also cleaves the iPQM relevant for heterodimerization of a subgroup of neurotoxins. An involvement in the maturing of cytolytic peptides is very likely, due to high similarity of present protease recognition motifs. Finally, bioinformatics analysis, identifying sequences of homolog proteins from 18 spiders of 9 families, demonstrate the wide distribution and importance of the isolated enzyme for spiders. In summary, we establish the first example of aPQMprotease, essential for maturing of spider venom neurotoxins. In the future, the here described protease may be established as a powerful tool for production strategies of recombinant toxic peptides, adapted to the maturing of spider venom toxins. [ABSTRACT FROM AUTHOR]