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International audience; Shards of Blue-and-White Ming porcelain from shipwrecks of Portuguese ships found on the coasts of South Africa plus a shard from Mombasa (Kenya) were analyzed by optical microscopy, SEM-EDS and Raman microspectroscopy (458 nm). Whereas the Raman signature of porcelain body paste compositions which are based on mullite, quartz and an amorphous phase with the minor presence of anatase and feldspar are very comparable whatever the variable alumina content, at least two types of glazes are observed: a high-temperature soda-potassium glaze, and glazes richer in calcium and similar to a celadon glaze (with the possibility of wollastonite formation). The blue decoration is obtained with a material rich in manganese typical of the Ming productions. Some shards exhibit a two-layer glaze and the blue decoration is either placed under-glaze, or in-glaze as found in the Vietnamese productions of the same period. Previous assignments of the Raman signature of feldspar to cobalt aluminate are now not favoured (blue colour is obtained with Co2+ ions dissolved in the glassy silicate) and several black spots exhibit the characteristic spectrum of an epsilon Fe2O3 phase being present.

Despite advances in breast cancer treatment, residual disease driven by dormant tumor cells continues to be a significant clinical problem. Leukemia inhibitory factor receptor (LIFR) promotes a dormancy phenotype in breast cancer cells and LIFR loss is correlated with poor patient survival. Herein, we demonstrate that histone deacetylase inhibitors (HDACi), which are in phase III clinical trials for breast cancer, epigenetically induced LIFR and activated a pro-dormancy program in breast cancer cells. HDACi slowed breast cancer cell proliferation and reduced primary tumor growth. Primary breast tumors from HDACi-treated patients had increased LIFR levels and reduced proliferation rates compared to pre-treatment levels. Recent Phase II clinical trial data studying entinostat and azacitidine in metastatic breast cancer revealed that induction of several pro-dormancy genes post-treatment was associated with prolonged patient survival. Together, these findings suggest HDACi as a potential therapeutic avenue to promote dormancy, prevent recurrence, and improve patient outcomes in breast cancer.

OBJECTIVES: Using caregiver report and urinary cotinine measures, we defined the prevalence of secondhand smoke (SHS) exposure among young, hospitalized children and compared exposure among those hospitalized with pneumonia versus those with acute, nonrespiratory illnesses. METHODS: Children aged RESULTS: Overall, 36% of the 239 enrolled children had reported home SHS exposure, although 77% had detectable levels of urinary cotinine, including 59% with heavy exposure. The highest urinary cotinine level was among children exposed to indoor smoking (7.78 ng/mL, interquartile range 2.93–18.65; P < .001). Increased SHS exposure was associated with non-Hispanic ethnicity, lower household educational attainment, and public insurance. There were no differences in SHS exposure by diagnosis. CONCLUSIONS: Among hospitalized young children, reported home SHS exposure was common but substantially underestimated when compared with urinary cotinine levels. The highest urinary cotinine levels were among children exposed to indoor smoking. Future public health interventions, as well as more robust SHS exposure screenings on hospital admission, are needed to reduce the prevalence of SHS exposure among young children.

In Roman wall paintings, blue and green colours are less commonly encountered than red and yellow and were more expensive. Despite this, Pliny and Vitruvius describe the more common compounds used for these pigments, translated today as azurite, lazurite, chrysocolla, indigo and Egyptian blue for blues and verdigris, malachite, celadonite, glauconite and chlorite for greens. A confusion in their nomenclature is often found in the most common blue pigment that is the first manufactured compound, Egyptian blue. For greens, celadonite and glauconite were usual and called generically ‘green earths’, but they prove to be difficult to characterize analytically. In this paper, we evaluate the Raman spectroscopic identification of the characteristic Roman blue and green pigments as used in wall paintings using two different laser wavelengths (green and near infrared) and clarify their nomenclature.

The nonapeptide hormone arginine vasotocin (VT) regulates osmotic balance in fishes by modulating ion and water transport. While VT’s osmoregulatory effects arise in part via changes in VT secretio...

Six mummies and their and cartonnages found at Tell Al Sawa, Eastern Delta, Egypt, provided 20 fragments of cartonnage for analysis to determine if the initial attribution of their age to the late period was correct. The cartonnage fragments were examined using SEM–EDAXS and FT-IR spectroscopy, and the results revealed that they comprised linen supports over a preparatory layer either of calcite or gypsum alone or in admixture mixed with organic binding medium of animal glue. The paint layer was applied using either natural mineral oxide earths such as iron oxide and lead oxide, strontium carbonate or the synthetic pigment Egyptian blue. The binding medium was found to be gum arabic. The pigment characterization revealed the unusual presence of a zinc silicate, noted in Egyptian painting for the first time.

Diffuse intrinsic pontine glioma is an aggressive pediatric cancer for which no effective chemotherapeutic drugs exist. Analysis of the genomic landscape of this disease has led to the identification of the serine/threonine kinase ALK2 as a potential target for therapeutic intervention. In this work, we adopted an open science approach to develop a series of potent type I inhibitors of ALK2 which are orally bio-available and brain-penetrant. Initial efforts resulted in the discovery of M4K2009, an analogue of the previously reported ALK2 inhibitor LDN-214117. Although highly selective for ALK2 over the TGF-βR1 receptor ALK5, M4K2009 is also moderately active against the hERG potassium channel. Varying the substituents of the trimethoxyphenyl moiety gave rise to an equipotent benzamide analogue M4K2149 with reduced off-target affinity for the ion channel. Additional modifications yielded 2-fluoro-6-methoxybenzamide derivatives (26a-c), which possess high inhibitory activity against ALK2, excellent selectivity, and superior pharmacokinetic profiles.

Staphylococcus aureus is a major human pathogen that utilises a wide array of pathogenic and immune evasion strategies to cause disease. One immune evasion strategy, common to many bacterial pathogens, is the ability of S. aureus to produce a capsule that protects the bacteria from several aspects of the human immune system. To identify novel regulators of capsule production by S. aureus, we applied a genome wide association study (GWAS) to a collection of 300 bacteraemia isolates that represent the two major MRSA clones in UK and Irish hospitals: CC22 and CC30. One of the loci associated with capsule production, the menD gene, encodes an enzyme critical to the biosynthesis of menadione. Mutations in this gene that result in menadione auxotrophy induce the slow growing small-colony variant (SCV) form of S. aureus often associated with chronic infections due to their increased resistance to antibiotics and ability to survive inside phagocytes. Utilising such an SCV, we functionally verified this association between menD and capsule production. Although the clinical isolates with polymorphisms in the menD gene in our collections had no apparent growth defects, they were more resistant to gentamicin when compared to those with the wild-type menD gene. Our work suggests that menadione is involved in the production of the S. aureus capsule, and that amongst clinical isolates polymorphisms exist in the menD gene that confer the characteristic increased gentamicin resistance, but not the major growth defect associated with SCV phenotype.

Details of the types of porcelain body encountered, the confusion in nomenclature and descriptions historically and their metal oxide compositions. True and artificial porcelain. The difference in manufacturing procedures that must also be considered alongside the basic chemical composition. The distinction between the highly phosphatic soft paste porcelain and bone china. Categorisation of hard paste, soft paste, glassy, magnesian, bone china, phosphatic and hybrid porcelain bodies and their semi-quantitative analytical content of silica, alumina, lime, magnesia, lead oxide, soda, potash and phosphorus pentoxide. Establishment of analytical protocols for the unequivocal identification of porcelain types form their elemental oxide analytical data and also from their molecular spectral mineralogical data. The correlation of analytical data with documentary recipes relating to compositional percentages of raw materials with examples cited from early European and Chinese porcelains. The definitive analytical role of trace element detection and its relationship with the source identification of raw materials and factory chronology. Examples are given of the use of zirconium, rubidium and strontium as trace elements for the authentication of some early pieces and the detection of trace elements in decorative enamels. The analytical concepts of accuracy, precision, errors and detection limits for the use of data presented in compositional analyses. The use of elemental oxide ratios, for example, potash, soda and lime, for the identification of porcelain factory origins and the pitfalls encountered therein.

Antibiotics inhibit essential bacterial processes, resulting in arrest of growth and, in some cases, cell death. Many antibiotics are also reported to trigger endogenous production of reactive oxygen species (ROS), which damage DNA, leading to induction of the mutagenic SOS response associated with the emergence of drug resistance. However, the type of DNA damage that arises and how this triggers the SOS response are largely unclear. We found that several different classes of antibiotic triggered dose-dependent induction of the SOS response in Staphylococcus aureus, indicative of DNA damage, including some bacteriostatic drugs. The SOS response was heterogenous and varied in magnitude between strains and antibiotics. However, in many cases, full induction of the SOS response was dependent upon the RexAB helicase/nuclease complex, which processes DNA double-strand breaks to produce single-stranded DNA and facilitate RecA nucleoprotein filament formation. The importance of RexAB in repair of DNA was confirmed by measuring bacterial survival during antibiotic exposure, with most drugs having significantly greater bactericidal activity against rexB mutants than against wild-type strains. For some, but not all, antibiotics there was no difference in bactericidal activity between wild type and rexB mutant under anaerobic conditions, indicative of a role for reactive oxygen species in mediating DNA damage. Taken together, this work confirms previous observations that several classes of antibiotics cause DNA damage in S. aureus and extends them by showing that processing of DNA double-strand breaks by RexAB is a major trigger of the mutagenic SOS response and promotes bacterial survival.

The Indian megacity of Delhi suffers from some of the poorest air quality in the world. While ambient NO2 and particulate matter (PM) concentrations have received considerable attention in the city, high ground-level ozone (O3) concentrations are an often overlooked component of pollution. O3 can lead to significant ecosystem damage and agricultural crop losses, and adversely affect human health. During October 2018, concentrations of speciated non-methane hydrocarbon volatile organic compounds (C2–C13), oxygenated volatile organic compounds (o-VOCs), NO, NO2, HONO, CO, SO2, O3, and photolysis rates, were continuously measured at an urban site in Old Delhi. These observations were used to constrain a detailed chemical box model utilising the Master Chemical Mechanism v3.3.1. VOCs and NOx (NO + NO2) were varied in the model to test their impact on local O3 production rates, P(O3), which revealed a VOC-limited chemical regime. When only NOx concentrations were reduced, a significant increase in P(O3) was observed; thus, VOC co-reduction approaches must also be considered in pollution abatement strategies. Of the VOCs examined in this work, mean morning P(O3) rates were most sensitive to monoaromatic compounds, followed by monoterpenes and alkenes, where halving their concentrations in the model led to a 15.6 %, 13.1 %, and 12.9 % reduction in P(O3), respectively. P(O3) was not sensitive to direct changes in aerosol surface area but was very sensitive to changes in photolysis rates, which may be influenced by future changes in PM concentrations. VOC and NOx concentrations were divided into emission source sectors, as described by the Emissions Database for Global Atmospheric Research (EDGAR) v5.0 Global Air Pollutant Emissions and EDGAR v4.3.2_VOC_spec inventories, allowing for the impact of individual emission sources on P(O3) to be investigated. Reducing road transport emissions only, a common strategy in air pollution abatement strategies worldwide, was found to increase P(O3), even when the source was removed in its entirety. Effective reduction in P(O3) was achieved by reducing road transport along with emissions from combustion for manufacturing and process emissions. Modelled P(O3) reduced by ∼ 20 ppb h−1 when these combined sources were halved. This study highlights the importance of reducing VOCs in parallel with NOx and PM in future pollution abatement strategies in Delhi.

Amyloid β proteins, including toxic soluble oligomers (SPOs) are not only found in the brain duringAlzheimer’s, but also in the peripheral vascular system. The precise mechanism linking increasedcirculating levels of SPOs and vascular dysfunction remains unknown. We hypothesized that SPOslead to endoplasmic reticulum (ER) stress, further release of SPOs and vascular injury. Mesentericresistance arteries (MRAs) from 14 weeks old, male and female C57BL/6 mice were used forvascular function. Agonists were acetylcholine and phenylephrine (1nM-10mM). In acuteconditions, SPOs (0.1μM) caused pathologically exacerbated endothelium-dependent vasodilationcompared to vehicle (F12 media) [Male: EC50: SPOs: -7.0 ± 0.1 (n=4), vs. Vehicle -6.6 ± 0.1 (n=7)p=0.03; Female: EC50: SPOs: -7.3 ± 0.06 (n=5) vs. Vehicle -6.7 ± 0.1 (n=6), p=0.001]. Thisphenotype was similar to the positive control tunicamycin (5mg/ml) [Male: EC50: Tunicamycin: -7.3(n=4), vs. Vehicle -6.6 (n=7) p=0.2; Female: EC50: Tunicamycin: -7.7 (n=4) vs. Vehicle -6.8 (n=5)p=0.04]. To determine whether SPO’s cause ER stress, arteries were treated with ER stressinhibitor 4-Phenylbutyric acid (2mM). The ER stress inhibitor prevented the exacerbatedvasodilation induced by SPOs showing SPOs trigger ER stress in acute conditions independent ofsex. To determine whether SPOs are a consequence of ER stress, arteries were incubated withtunicamycin in the presence of the SPO inhibitor K01-162 (10mM). Interestingly, K01-162 did notprevent the tunicamycin-induced exacerbated vasodilation in arteries from male mice. However,this response was decreased in arteries from female mice showing that inducing ER stress leadsto the release of SPOs, escalating a feed-forward mechanism of further SPO release. There wereno changes in vascular contraction with tunicamycin or SPOs irrespective of sex. ER stress wasconfirmed with anti-KDEL antibody staining, specific for ER resident chaperones Grp78/94 andvisualized with multiphoton fluorescent confocal microscopy. These results demonstrate that SPO’sexacerbate endothelium-dependent vasodilation acutely and may contribute to brain and peripheralvascular edema and loss of autoregulation observed during cardiovascular and Alzheimer’sdisease.

Patients with multiple myeloma (MM), an incurable malignancy of plasma cells, frequently develop osteolytic bone lesions. In this study, glycosphingolipids were essential in promoting autophagic degradation of the signaling molecule TRAF3, a key step in bone-resorbing osteoclast differentiation. Specifically altering the glycosphingolipid composition with eliglustat, an FDA approved glucosylceramide synthase inhibitor, arrested osteoclast differentiation; this could be rescued by exogenous addition of the missing glycosphingolipids. Eliglustat significantly reduced bone disease in several preclinical models of MM by inhibiting osteoclastogenesis and, due to its unique mode of action, it was able to act in combination with existing bone protective drugs. Furthermore, eliglustat arrested osteoclast differentiation from the bone marrow of MM patients in a glycosphingolipid-dependent way. This work identifies both the mechanism by which glucosylceramide synthase inhibition blocks autophagic degradation of TRAF3 to reduce osteoclastogenesis as well as highlighting the translational potential of eliglustat to be combined with current treatments.

Iron-Sulfur (Fe-S) clusters function as core prosthetic groups known to modulate the activity of metalloenzymes, act as trafficking vehicles for biological iron and sulfur, and participate in several intersecting metabolic pathways. The formation of these clusters is initiated by a class of enzymes called cysteine desulfurases, whose primary function is to shuttle sulfur from the amino acid L-cysteine to a variety of sulfur transfer proteins involved in Fe-S cluster synthesis as well as in the synthesis of other thiocofactors. Thus, sulfur and Fe-S cluster metabolism are connected through shared enzyme intermediates, and defects in their associated pathways cause a myriad of pleiotropic phenotypes, which are difficult to dissect. Post-transcriptionally modified transfer RNA (tRNA) represents a large class of analytes whose synthesis often requires the coordinated participation of sulfur transfer and Fe-S enzymes. Therefore, these molecules can be used as biologically relevant readouts for cellular Fe and S status. Methods employing LC-MS technology provide a valuable experimental tool to determine the relative levels of tRNA modification in biological samples and, consequently, to assess genetic, nutritional, and environmental factors modulating reactions dependent on Fe-S clusters. Herein, we describe a robust method for extracting RNA and analytically evaluating the degree of Fe-S-dependent and -independent tRNA modifications via an LC-MS platform.

Colistin is a polymyxin antibiotic of last resort for the treatment of infections caused by multi-drug-resistant Gram-negative bacteria. By targeting lipopolysaccharide (LPS), the antibiotic disrupts both the outer and cytoplasmic membranes, leading to bacterial death and lysis. Colistin resistance in Escherichia coli occurs via mutations in the chromosome or the acquisition of mobilized colistin-resistance (mcr) genes. Both these colistin-resistance mechanisms result in chemical modifications to the LPS, with positively charged moieties added at the cytoplasmic membrane before the LPS is transported to the outer membrane. We have previously shown that MCR-1-mediated LPS modification protects the cytoplasmic but not the outer membrane from damage caused by colistin, enabling bacterial survival. However, it remains unclear whether this observation extends to colistin resistance conferred by other mcr genes, or resistance due to chromosomal mutations. Using a panel of clinical E. coli that had acquired mcr −1, –1.5, −2, –3, −3.2 or −5, or had acquired polymyxin resistance independently of mcr genes, we found that almost all isolates were susceptible to colistin-mediated permeabilization of the outer, but not cytoplasmic, membrane. Furthermore, we showed that permeabilization of the outer membrane of colistin-resistant isolates by the polymyxin is in turn sufficient to sensitize bacteria to the antibiotic rifampicin, which normally cannot cross the LPS monolayer. These findings demonstrate that colistin resistance in these E. coli isolates is due to protection of the cytoplasmic but not outer membrane from colistin-mediated damage, regardless of the mechanism of resistance.

OBJECTIVES:. Extracorporeal membrane oxygenator support is a powerful clinical tool that is currently enjoying a resurgence in popularity. Wider use of extracorporeal membrane oxygenator support is limited by its significant risk profile and extreme consumption of resources. This study examines the role of markers of liver dysfunction in predicting outcomes of adult patients requiring extracorporeal membrane oxygenator support. DESIGN:. Retrospective review. SETTING:. Large extracorporeal membrane oxygenator center, Chicago, IL. PATIENTS:. This study reports a single institution experience examining all adult patients for whom extracorporeal membrane oxygenator support was used over an 8-year period. Data were collected regarding patient demographics, details of extracorporeal membrane oxygenator support provided, laboratory data, and outcomes. Trends in liver function were examined for their ability to predict survival. INTERVENTION:. Extracorporeal membrane oxygenator support, critical care. MEASUREMENTS AND MAIN RESULTS:. Mean age was 50 years (range, 19–82 yr). There were 86 male patients (56.6%) and 66 female patients (43.4%). Indications for initiation of extracorporeal membrane oxygenator support included cardiac 76 patients (50.0%), respiratory 48 patients (31.6%), extracorporeal cardiopulmonary resuscitation 21 patients (13.3%), and combined cardiac/respiratory seven patients (4.6%). Mean duration of extracorporeal membrane oxygenator support was 17 days (range 1–223 d) or median 8 days (interquartile range, 4–17 d). Overall, in-hospital mortality was 56% (86/152). Forty-five percent of adult patients (68/152) surpassed at least one of the following established liver dysfunction thresholds: total bilirubin greater than 15 mg/dL, aspartate aminotransferase greater than 20× upper limit of normal, and alanine aminotransferase greater than 20× upper limit of normal. The multivariable logistic analysis yielded three significant findings associated with in-hospital mortality: highest total bilirubin greater than 15 (adjusted odds ratio = 4.40; 95% CI, 1.19–21.87; p = 0.04), age (adjusted odds ratio = 1.03; 95% CI, 1.00–1.05; p = 0.04), and highest lactate (adjusted odds ratio = 1.15; 95% CI, 1.06–1.26; p = 0.002). CONCLUSIONS:. Increases in age, highest total bilirubin, and lactate all correlated with in-hospital mortality in multivariable analysis of patients requiring extracorporeal membrane oxygenator support.

Previous studies have indicated that oxytocin (OT) reduces body weight in diet-induced obese (DIO) rodents through reductions in energy intake and increases in energy expenditure. We recently demonstrated that hindbrain [fourth ventricular (4V)] administration of OT evokes weight loss and elevates interscapular brown adipose tissue temperature (TIBAT) in DIO rats. What remains unclear is whether OT can be used as an adjunct with other drugs that directly target beta-3 receptors in IBAT to promote BAT thermogenesis and reduce body weight in DIO rats. We hypothesized that the combined treatment of OT and the beta-3 agonist, CL 316243, would produce an additive effect to decrease body weight and adiposity in DIO rats by reducing energy intake and increasing BAT thermogenesis. We assessed the effects of 4V infusions of OT (16 nmol/day) or vehicle (VEH) in combination with daily intraperitoneal injections of CL 316243 (0.5 mg/kg) or VEH on food intake, TIBAT, body weight and body composition. OT and CL 316243 alone reduced body weight by 7.8 ± 1.3% (P < 0.05) and 9.1 ± 2.1% (P < 0.05), respectively, but the combined treatment produced more pronounced weight loss (15.5 ± 1.2%; P < 0.05) than either treatment alone. These effects were associated with decreased adiposity, adipocyte size, energy intake and increased uncoupling protein 1 (UCP-1) content in epididymal white adipose tissue (EWAT) (P < 0.05). In addition, CL 316243 alone (P < 0.05) and in combination with OT (P < 0.05) elevated TIBAT and IBAT UCP-1 content and IBAT thermogenic gene expression. These findings are consistent with the hypothesis that the combined treatment of OT and the beta-3 agonist, CL 316243, produces an additive effect to decrease body weight. The findings from the current study suggest that the effects of the combined treatment on energy intake, fat mass, adipocyte size and browning of EWAT were not additive and appear to be driven, in part, by transient changes in energy intake in response to OT or CL 316243 alone as well as CL 316243-elicited reduction of fat mass and adipocyte size and induction of browning of EWAT.

The current date labeling system for pasteurized milk is based on the predicted growth of spoilage microorganisms, but inherent inaccuracies and the inability to account for environmental factors (e.g., temperature fluctuations) contribute to household and retail food waste. Improved shelf-life estimation can be achieved by monitoring milk quality in real-time. In this study, we identify and quantify metabolites changing over storage temperature and time, the main factors affecting milk stability. Pasteurized 2% fat milk was stored at 4, 10, 15, and 20 °C. Metabolite change was analyzed using untargeted and targeted nuclear magnetic resonance (NMR) metabolomics approaches. Several metabolites correlated significantly to storage time and temperature. Citric acid decreased linearly over time at a temperature-dependent rate. Ethanol, formic acid, acetic acid, lactic acid, and succinic acid increased non-linearly after an initial period of minimal increase. Butyric acid exhibited strong inverse temperature dependencies. This study provides the first analysis of the effect of time and temperature on the concentration of key metabolites during milk storage. Candidate molecules for shelf-life monitoring have been identified, and the results improve our understanding of molecular changes during milk storage. These results will inform the development of real-time shelf-life indicators for milk, helping to reduce milk waste.

Mural paintings within the tomb of Setka, Qubbet el-Hawa, in Aswan, Upper Egypt, were investigated using a multi-disciplinary analytical approach (Stereomicroscopy, SEM-EXD and FT-IR spectroscopy). The walls of the tomb were hewn from fragile sandstone and covered by a clay plaster, overlaid by two layers of white gypsum plaster. SEM micrographs were indicative of the penetration of fungal mycelium within the pores of the gypsum plaster, forming white encrustations due to the re-precipitation of gypsum. SEM micrographs revealed that the calcification of the gypsum plaster had occurred due to its exposure to a high temperature. The EDX pattern for the white plaster gave the characteristic spectrum of gypsum, the blue pigment was Egyptian blue, the black pigment was magnetite, the white pigment was of gypsum (or anhydrite) and the yellow pigment was limonite. Finally, the FT-IR spectrum of the binder gave the characteristic features of gum Arabic.

Colistin is an antibiotic of last resort, but has poor efficacy and resistance is a growing problem. Whilst it is well established that colistin disrupts the bacterial outer membrane (OM) by selectively targeting lipopolysaccharide (LPS), it was unclear how this led to bacterial killing. We discovered that MCR-1 mediated colistin resistance in Escherichia coli is due to modified LPS at the cytoplasmic rather than OM. In doing so, we also demonstrated that colistin exerts bactericidal activity by targeting LPS in the cytoplasmic membrane (CM). We then exploited this information to devise a new therapeutic approach. Using the LPS transport inhibitor murepavadin, we were able to cause LPS accumulation in the CM of Pseudomonas aeruginosa, which resulted in increased susceptibility to colistin in vitro and improved treatment efficacy in vivo. These findings reveal new insight into the mechanism by which colistin kills bacteria, providing the foundations for novel approaches to enhance therapeutic outcomes., eLife digest Antibiotics are life-saving medicines, but many bacteria now have the ability to resist their effects. For some infections, all frontline antibiotics are now ineffective. To treat infections caused by these highly resistant bacteria, clinicians must use so-called ‘antibiotics of last resort’. These antibiotics include a drug called colistin, which is moderately effective, but often fails to eradicate the infection. One of the challenges to making colistin more effective is that its mechanism is poorly understood. Bacteria have two layers of protection against the outside world: an outer cell membrane and an inner cell membrane. To kill them, colistin must punch holes in both. First, it disrupts the outer membrane by interacting with molecules called lipopolysaccharides. But how it disrupts the inner membrane was unclear. Bacteria have evolved several different mechanisms that make them resistant to the effects of colistin. Sabnis et al. reasoned that understanding how these mechanisms protected bacteria could reveal how the antibiotic works to damage the inner cell membrane. Sabnis et al. examined the effects of colistin on Escherichia coli bacteria with and without resistance to the antibiotic. Exposing these bacteria to colistin revealed that the antibiotic damages both layers of the cell surface in the same way, targeting lipopolysaccharide in the inner membrane as well as the outer membrane. Next, Sabnis et al. used this new information to make colistin work better. They found that the effects of colistin were magnified when it was combined with the experimental antibiotic murepavadin, which caused lipopolysaccharide to build up at the inner membrane. This allowed colistin to punch more holes through the inner membrane, making colistin more effective at killing bacteria. To find out whether this combination of colistin and murepavadin could work as a clinical treatment, Sabnis et al. tested it on mice with Pseudomonas aeruginosa infections in their lungs. Colistin was much better at killing Pseudomonas aeruginosa and treating infections when combined with murepavadin than it was on its own. Pseudomonas aeruginosa bacteria can cause infections in the lungs of people with cystic fibrosis. At the moment, patients receive colistin in an inhaled form to treat these infections, but it is not always successful. The second drug used in this study, murepavadin, is about to enter clinical trials as an inhaled treatment for lung infections too. If the trial is successful, it may be possible to use both drugs in combination to treat lung infections in people with cystic fibrosis.

Altres ajuts: This work also received a grant from the Spanish Society of Pneumology and Thoracic Surgery (SEPAR 024/2016). M.L. gratefully acknowledges funding from the European Respiratory Society Long-term Fellowship grant (LTRF-5934). A.M.E. acknowledges funding from the Royal Society, Department of Medicine (Imperial College), and from the Imperial NIHR Biomedical Research Centre, Imperial College London. B.C.Y is funded by an NIHR Clinical Lectureship. CP acknowledges Programa Germans Trias Sapiens Fundació Catalunya la Pedrera and European Respiratory Society short term research fellowship October 2018 (STRTF201810-00467). Tobacco smoking represents the leading preventable cause of death worldwide. Smoking is a recognised risk factor for several pathologies and is detrimental to host immune surveillance and defence. However, the impact of smoking on microbial residents of the nasopharyngeal cavity, in contact with cigarette smoke (CS), is lacking. Staphylococcus aureus is a major human pathogen that colonises the human nasopharynx and causes a wide range of infections. We investigated the impact of CS on specific virulence phenotypes important in S aureus pathogenesis. We observed strain-dependent differences following exposure to CS, namely growth inhibition, augmented biofilm formation, increased invasion of, and persistence within, bronchial alveolar epithelial cells. Additionally, we confirm the critical role of a functional accessory gene regulator (Agr) system in mediating increased biofilm development and host cell invasion and persistence following CS exposure. Furthermore, CS exposure resulted in reduced toxin production. Importantly, exposure of S aureus to CS accelerated the frequency of mutations and resulted in a significant increase in gentamicin-resistant small colony variant (SCV) formation. Mutational analysis revealed that CS induced SCVs emerge via the SOS response DNA mutagenic repair system. Taken together, our results suggest that CS redirects certain S aureus strains to a virulence profile associated with persistence.

Research was conducted from 2013 to 2015 across three sites in Mississippi to evaluate corn response to sublethal paraquat or fomesafen (105 and 35 g ai ha−1, respectively) applied PRE, or to corn at the V1, V3, V5, V7, or V9 growth stages. Fomesafen injury to corn at three d after treatment (DAT) ranged from 0% to 38%, and declined over time. Compared with the nontreated control (NTC), corn height 14 DAT was reduced approximately 15% due to fomesafen exposure at V5 or V7. Exposure at V1 or V7 resulted in 1,220 and 1,110 kg ha−1 yield losses, respectively, compared with the NTC, but yield losses were not observed at any other growth stage. Fomesafen exposure at any growth stage did not affect corn ear length or number of kernel rows relative to the NTC. Paraquat injury to corn ranged from 26% to 65%, depending on growth stage and evaluation interval. Corn exposure to paraquat at V3 or V5 consistently caused greater injury across evaluation intervals, compared with other growth stages. POST timings of paraquat exposure resulted in corn height reductions of 13% to 50%, except at V7, which was most likely due to rapid internode elongation at that stage. Likewise, yield loss occurred after all exposure times of paraquat except PRE, compared with the NTC. Corn yield was reduced 1,740 to 5,120 kg ha−1 compared with the NTC, generally worsening as exposure time was delayed. Paraquat exposure did not reduce corn ear length, compared with the NTC, at any growth stage. However, paraquat exposure at V3 or V5 was associated with reduction of kernel rows by 1.1 and 1.7, respectively, relative to the NTC. Paraquat and fomesafen applications near corn should be avoided if conditions are conducive for off-target movement, because significant injury and yield loss can result.

This study investigated the effect of a novel phosphorylated tocopherol mixture (TPM) on the growth performance, nutrient digestibility, meat quality, and blood plasma markers of inflammation in broilers reared in normal temperatures (NT) or cyclical high temperatures (CHT). TPM has previously been shown to increase the oral bioavailability of lipid soluble nutrients. Following a preliminary dose optimisation study, three hundred and sixty Ross 308 day old broilers were housed in groups of 5 in cages ( n = 12). Treatments were arranged in a factorial design encompassing 3 dietary TPM levels and ± CHT. From day of placement until d 35, broilers were assigned to 1 of 3 vitamin E-adequate, wheat and soybean meal-based diets containing TPM at 0 (Control), 10 or 20 mg/kg diet. From 21-35 d of age, birds were exposed to either normal temperatures (NT; 22 ± 1 °C; 60% RH) or cyclical high temperature (CHT; 32 ± 1 °C; 8 h; 80–90% RH and 16 h at 22 ± 1 °C; 60% RH). Implementing CHT negatively impacted feed intake (FI), body weight (BW) gain, feed conversion ratio (FCR) and final BW (d 35), apparent ileal digestibility (AID) and shear force of cooked breast muscle. Under both NT and CHT regimes, the TPM 10 group had improved BW gain (d 0-35), FCR (d 0-21) and final BW (d 35) when compared with Control diet groups containing TPM at 0. There was an interaction between diet and temperature regime on AID. The TPM 20 + CHT group had decreased AID of nitrogen (N) and gross energy (GE) when compared with the TPM 20 + NT group. However, there was no effect of the Control or TPM 10 on AID under either temperature regime. Breast muscle from CHT birds had increased temperature and shear force when cooked, and decreased pH and drip loss when compared with NT birds. The TPM 10 group tended to have lower drip loss (P = 0.057) under both temperature regimes when compared with the Control group. Implementing CHT increased the plasma concentration of select cytokines and chemokines (INFγ, IL-6, IL-10, IL-16, IL-21 and CCL5) when compared with the NT treatment. Birds offered the TPM 10 diets had numerically lower concentrations of all plasma chemokines and cytokines when compared with the Control diets. In summary, CHT depressed performance and nutrient digestibility and negatively impacted breast muscle quality. The TPM 10 treatment improved growth performance variables under both NT and CHT regimes and tended to reduce muscle drip loss.

Eight out of 46 strains of Streptomyces isolated from mural paintings in the Tell Basta and Tanis tombs were exposed to various doses of gamma radiation (5, 10, 15, 20, 25 kGy). Tricyclazole (5, 7, 10 µg/mL) in dimethyl sulfoxide (DMSO) at 10 µg/mL completely inhibited melanin production in Streptomyces spp. after their gamma irradiation to sub-lethal doses. FT/IR spectra proved that the gypsum support, the binding media (which consisted of Arabic gum, and animal glue), and pigments all had withstood the doses up to 25 kGy, with except vermillion showed slight change. No effect of gamma irradiation up to 25 kGy on gypsum support was detected, so gamma irradiation could be considered a safe method for decontamination of biodeteriorated cultural heritage objects.

[Image: see text] Expression of β-lactamase is the single most prevalent determinant of antibiotic resistance, rendering bacteria resistant to β-lactam antibiotics. In this article, we describe the development of an antibiotic prodrug that combines ciprofloxacin with a β-lactamase-cleavable motif. The prodrug is only bactericidal after activation by β-lactamase. Bactericidal activity comparable to ciprofloxacin is demonstrated against clinically relevant E. coli isolates expressing diverse β-lactamases; bactericidal activity was not observed in strains without β-lactamase. These findings demonstrate that it is possible to exploit antibiotic resistance to selectively target β-lactamase-producing bacteria using our prodrug approach, without adversely affecting bacteria that do not produce β-lactamase. This paves the way for selective targeting of drug-resistant pathogens without disrupting or selecting for resistance within the microbiota, reducing the rate of secondary infections and subsequent antibiotic use.

The first catalytic strategy to harness imidate radicals for C–H functionalization has been developed. This iodine-catalyzed approach enables β C–H amination of alcohols by an imidate-mediated radical relay. In contrast to our first-generation, (super)stoichiometric protocol, this catalytic method enables faster and more efficient reactivity. Furthermore, lower oxidant concentration affords broader functional group tolerance, including alkenes, alkynes, alcohols, carbonyls, and heteroarenes. Mechanistic experiments interrogating the electronic nature of the key 1,5 H-atom transfer event are included, as well as probes for chemo-, regio-, and stereo-selectivity.

[EN] An analysis of literature data studying the composition and color of Maya blue (MB) type materials prepared from indigo, dehydroindigo, and different aluminosilicates, accompanied by new spectral data, is presented. After thermal treatment at above 100 degrees C, indigo-based specimens displayed Raman and UV-vis spectroscopic features common to those of equivalent dehydroindigo-based replicants, thus supporting the socalled dehydroindigo model (J. Phys. Chem. B 2006, 110, 6027-6039) in which the dehydroindigo/indigo ratio, increasing with temperature, is crucial to determine the color of MB and its variability. The current analysis supports the view of MB as a polyfunctional hybrid material just characterized by the presence of different organic components, each one distributed in topological isomers differently attached to the clay support. On the basis of the comparison of spectral data for different channeled silicates (among others, palygorskite, sepiolite, and montmorillonite clays, and different zeolites), we proposed a view on the color characteristics of Maya blue-type specimens as defined by the compromise between trapping ability for indigo molecules and facility to promote the oxidation of indigo to dehydroindigo., Project CTQ2017-85317-C2-1-P, supported with Ministerio de Economia, Industria y Competitividad (MINECO), Fondo Europeo de Desarrollo Regional (ERDF), and Agencia Estatal de Investigacion (AEI) is gratefully acknowledged.

Future ground-level concentrations of phytotoxic ozone are projected to grow in the Northern Hemisphere, at a rate depending on emission scenarios. We explored the likely changes in net ecosystem production (NEP) due to the increasing concentration of tropospheric ozone by applying a Generalized Additive Mixed Model based on measurements of ozone concentration ([O3]) and stomatal ozone flux (FsO3), at a mountainous Norway spruce forest in the Czech Republic, Central Europe. A dataset covering the growing period (May-August 2009) was examined in this case study. A predictive model based on FsO3 was found to be marginally more accurate than a model using [O3] alone for prediction of the course of NEP when compared to NEP measured by the eddy covariance technique. Both higher [O3] and FsO3 were found to reduce NEP. NEP simulated at low, pre-industrial FsO3 (0.5 nmol m-2 s-1) was higher by 24.8% as compared to NEP assessed at current rates of FsO3 (8.32 nmol m-2 s-1). However, NEP simulated at high FsO3 (17 nmol m-2 s-1), likely in the future, was reduced by 14.1% as compared to NEP values at current FsO3. The interaction between environmental factors and stomatal conductance is discussed in this paper.

Antibiotics inhibit essential bacterial processes, resulting in arrest of growth and in some cases cell death. Many antibiotics are also reported to trigger endogenous production of reactive oxygen species (ROS), which damage DNA and other macromolecules. However, the type of DNA damage that arises and the mechanisms used by bacteria to repair it are largely unclear. We found that several different classes of antibiotic triggered dose-dependent DNA damage in Staphylococcus aureus, including some bacteriostatic drugs. Damage was heterogenous and varied in magnitude between strains. However, antibiotic-triggered DNA damage led to double strand breaks, the processing of which by the RexAB helicase/nuclease complex triggered the SOS response and reduced staphylococcal susceptibility to most of the antibacterials tested. In most cases, DNA DSBs occurred under aerobic but not anaerobic conditions, suggesting a role for ROS. We conclude that DNA double strand breaks are a common occurrence during bacterial exposure to several different antibiotic classes and that repair of this damage by the RexAB complex promotes bacterial survival.

Cell death has long been a characteristic phenotype of organ damage in hypertension, and recently, leaky gut has been revealed as a novel hypertensive phenotype. However, despite the increase in bacterial and damaged mitochondrial products in the circulation of hypertensive patients and animals, the mechanistic contribution of these two phenomena to hypertension pathophysiology is unknown. Mitochondria and bacteria both start protein translation with an N-formyl methionine residue and thus are the only sources of NFPs (N-formyl peptides), which activate the FPR-1 (formyl peptide receptor-1). We hypothesized that the synergistic action of bacterial and mitochondrial NFPs would cause the spontaneous elevation of blood pressure and vascular remodeling in male Dahl salt-sensitive rats via FPR-1. We observed that mitochondria-derived peptides originating from cell death in the kidneys are responsible for FPR-1–induced vascular hypercontractility and remodeling and premature elevation of BP in Dahl salt-sensitive rats fed a low-salt diet. However, a high-salt diet leads to gut barrier disruption and, subsequently, a synergistic action of mitochondria, and bacteria-derived leaky gut NFPs lead to a severe and established hypertension. Administration of an FPR-1 antagonist lowered blood pressure in Dahl salt-sensitive rats on a low-salt diet but amoxicillin administration did not. These results reveal for the first time that cell death can be a cause of hypertensive pathophysiology, whereas leaky gut is a consequence.

The process of ribosomal recoding is generally regulated by an autonomous mRNA signal downstream of stop-codons. While structural studies have provided mechanistic insights into viral systems, no such studies exist in mammalian systems. Here we define a novel structural mechanism for the VEGF-A readthrough system and show that regulation is multifaceted and complex, requiring a multipartite set of RNA elements located at long distances that interact with each other and with hnRNP A2/B1 to synergistically enhance readthrough levels. The Ax-element downstream of the stop codon adopts a unique multistem (SL-Ax1-3) architecture: SL-Ax1 interacts with hnRNP A2/B1, while SL-Ax2 interacts with an RNA element (SL-Au1) located ~500 nt upstream at the start of the coding sequence. SL-Au1 also independently binds to hnRNP A2/B1, which manipulates an equilibrium between alternate structures— from a sequestered bulge towards one that allows for the long-range interaction with SL-Ax2. Overall, our study not only highlights the significance of structural organization of elements within the coding sequence of mRNA, but also provides a functional relevance of the closed-loop mRNA organization in non-canonical translation and suggests complex mechanisms allow for finer integration of many signals for a required output.

The impact of emissions of volatile organic compounds (VOCs) to the atmosphere on the production of secondary pollutants, such as ozone and secondary organic aerosol (SOA), is mediated by the concentration of nitric oxide (NO). Polluted urban atmospheres are typically considered to be “high-NO” environments, while remote regions such as rainforests, with minimal anthropogenic influences, are considered to be “low NO”. However, our observations from central Beijing show that this simplistic separation of regimes is flawed. Despite being in one of the largest megacities in the world, we observe formation of gas- and aerosol-phase oxidation products usually associated with low-NO “rainforest-like” atmospheric oxidation pathways during the afternoon, caused by extreme suppression of NO concentrations at this time. Box model calculations suggest that during the morning high-NO chemistry predominates (95 %) but in the afternoon low-NO chemistry plays a greater role (30 %). Current emissions inventories are applied in the GEOS-Chem model which shows that such models, when run at the regional scale, fail to accurately predict such an extreme diurnal cycle in the NO concentration. With increasing global emphasis on reducing air pollution, it is crucial for the modelling tools used to develop urban air quality policy to be able to accurately represent such extreme diurnal variations in NO to accurately predict the formation of pollutants such as SOA and ozone.

Whereas some prior studies have explored whether alcohol increases the risk for victimization and/or whether distress resulting from victimization increases the risk for alcohol use, few studies have simultaneously tested these bidirectional hypotheses among a high-risk sample (i.e., undergraduate women), while including both sexual assault (SA) and intimate partner violence (IPV) victimization, and while exploring potential moderating effects of PTSD symptoms on these paths. Among 631 college women, the present study tested these bidirectional associations using cross-lagged panel models across two measurement periods (i.e., Time 1 [T1] and Time 2 [T2], six months later). Results suggested that T1 alcohol use increased risk for T2 SA (but not T2 IPV victimization), and PTSD symptoms moderated this association; at lower levels of PTSD symptoms, there were no significant associations between alcohol use and subsequent SA victimization, whereas at higher levels of PTSD symptoms, alcohol use predicted subsequent SA victimization. By contrast, the opposite directional hypothesis was not supported; neither T1 lifetime SA nor IPV were associated with T2 drinking, regardless of the level of their PTSD symptoms. Prevention and intervention efforts should simultaneously address risk factors for alcohol use and victimization using trauma-informed practices.

Amyloid-β (Aβ) peptide aggregation into soluble oligomers and insoluble plaques is a precipitating event in the pathogenesis of Alzheimer's disease (AD). Given that synaptic activity can regulate Aβ generation, we postulated that 5HT2A -Rs may regulate Aβ as well. We treated APP/PS1 transgenic mice with the selective 5HT2A inverse agonists M100907 or Pimavanserin systemically and measured brain interstitial fluid (ISF) Aβ levels in real-time using in vivo microdialysis. Both compounds reduced ISF Aβ levels by almost 50% within hours, but had no effect on Aβ levels in 5HT2A -R knock-out mice. The Aβ-lowering effects of Pimavanserin were blocked by extracellular-regulated kinase (ERK) and NMDA receptor inhibitors. Chronic administration of Pimavanserin by subcutaneous osmotic pump to aged APP/PS1 mice significantly reduced CSF Aβ levels and Aβ pathology and improved cognitive function in these mice. Pimavanserin is FDA-approved to treat Parkinson's disease psychosis, and also has been shown to reduce psychosis in a variety of other dementia subtypes including Alzheimer's disease. These data demonstrate that Pimavanserin may have disease-modifying benefits in addition to its efficacy against neuropsychiatric symptoms of Alzheimer's disease. Read the Editorial Highlight for this article on page 560.

Biological iron-sulfur (Fe-S) clusters are essential protein prosthetic groups that promote a range of biochemical reactions. In vivo, these clusters are synthesized by specialized protein machineries involved in sulfur mobilization, cluster assembly, and cluster transfer to their target proteins. Cysteine desulfurases initiate the first step of sulfur activation and mobilization in cluster biosynthetic pathways. The reaction catalyzed by these enzymes involves the abstraction of sulfur from the amino acid l-cysteine, with concomitant formation of alanine. The presence and availability of a sulfur acceptor modulate the sulfurtransferase activity of this class of enzymes by altering their reaction profile and catalytic turnover rate. Herein, we describe two methods used to probe the reaction profile of cysteine desulfurases through quantification of alanine and sulfide production in these reactions.

We investigated the biomaterial interface between the bacteria Escherichia coli DH5α and silicon nanowire patterned surfaces. We optimised the engineering of silicon nanowire coated surfaces using metal-assisted chemical etching. Using a combination of focussed ion beam scanning electron microscopy, and cell viability and transformation assays, we found that with increasing interfacing force, cell viability decreases, as a result of increasing cell rupture. However, despite this aggressive interfacing regime, a proportion of the bacterial cell population remains viable. We found that the silicon nanowires neither resulted in complete loss of cell viability nor partial membrane disruption and corresponding DNA plasmid transformation. Critically, assay choice was observed to be important, as a reduction-based metabolic reagent was found to yield false-positive results on the silicon nanowire substrate. We discuss the implications of these results for the future design and assessment of bacteria–nanostructure interfacing experiments., In this study nanowires were engineered and we investigated the interface between the biomaterial and bacteria, looking in detail at membrane rupture and cell viability.

The renin-angiotensin system plays a key role in the regulation of blood pressure, fluid and electrolyte balance, and blood volume. In the initial step of the biochemical cascade, the proteolytic enzyme renin catalyzes the breakdown of the high-molecular-weight peptide, angiotensinogen, to angiotensin I. The report of the benzylimidazole 1 sparked our interest in the application of an overlay hypothesis strategy to aid in the design of nonpeptide angiotensin II antagonists. Careful examination of existing AII peptide structure-activity relationship helped refine our overlay hypothesis strategy and focus our synthetic efforts. Thus, a Tyr-Phe overlay hypothesis became the focus of our molecular modeling efforts. According to this overlay hypothesis, the small molecule covered the Tyr aromatic ring, Ile sidechain, and the Phe carboxylate of AII but failed to reach other regions of the octapeptide known to be important for affinity, such as the Arg and His sidechains and Phe aromatic ring.