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Relative abundances of bacterial species in the gut microbiome have been linked to many diseases. Species of gut bacteria are ecologically differentiated by their abilities to metabolize different glycans, making glycan delivery a powerful way to alter the microbiome to promote health. Here, we study the properties and therapeutic potential of chemically diverse synthetic glycans (SGs). Fermentation of SGs by gut microbiome cultures results in compound-specific shifts in taxonomic and metabolite profiles not observed with reference glycans, including prebiotics. Model enteric pathogens grow poorly on most SGs, potentially increasing their safety for at-risk populations. SGs increase survival, reduce weight loss, and improve clinical scores in mouse models of colitis. Synthetic glycans are thus a promising modality to improve health through selective changes to the gut microbiome. Here, the authors characterize the gut microbiome fermentation properties and therapeutic potential of chemically diverse synthetic glycans (SGs), showing they promote specific shifts in taxonomic and metabolite profiles, and exhibit therapeutic benefits in mouse models of colonic inflammation, together implying SGs as a potential avenue to treat disease by modulating the composition and metabolites produced by the gut microbiome.

A screen for compounds that inhibit disulfide bond formation in β-galactosidase in Escherichia coli found inhibitors of the membrane enzyme DsbB. Given the importance of DsbB in bacterial virulence, the inhibitors are potentially useful as antibacterials. In bacteria, disulfide bonds confer stability on many proteins exported to the cell envelope or beyond. These proteins include numerous bacterial virulence factors, and thus bacterial enzymes that promote disulfide bond formation represent targets for compounds inhibiting bacterial virulence. Here, we describe a new target- and cell-based screening methodology for identifying compounds that inhibit the disulfide bond–forming enzymes Escherichia coli DsbB ( Ec DsbB) or Mycobacterium tuberculosis VKOR ( Mtb VKOR), which can replace Ec DsbB, although the two are not homologs. Initial screening of 51,487 compounds yielded six specifically inhibiting Ec DsbB. These compounds share a structural motif and do not inhibit Mtb VKOR. A medicinal chemistry approach led us to select related compounds, some of which are much more effective DsbB inhibitors than those found in the screen. These compounds inhibit purified DsbB and prevent anaerobic growth of E. coli . Furthermore, these compounds inhibit all but one of the DsbBs of nine other Gram-negative pathogenic bacteria tested.

Bacteroides fragilis can replicate in atmospheres containing ≤0.05% oxygen, but higher concentrations arrest growth by an unknown mechanism. Here we show that inactivation of a single gene, oxe (i.e., oxygen enabled) in B. fragilis allows for growth in concentrations as high as 2% oxygen while increasing the tolerance of this organism to room air. Known components of the oxidative stress response including the ahpC , kat , batA-E , and tpx genes were not individually important for microaerobic growth. However, a Δ oxe strain scavenged H ₂O ₂ at a faster rate than WT, indicating that reactive oxygen species may play a critical role in limiting growth of this organism to low-oxygen environments. Clinical isolates of B. fragilis displayed a greater capacity for growth under microaerobic conditions than fecal isolates, with some encoding polymorphisms in oxe . Additionally, isolation of oxygen-enabled mutants of Bacteroides thetaiotaomicron suggests that Oxe may mediate growth arrest of other anaerobes in oxygenated environments.

Bacteroides fragilis can replicate in atmospheres containing ≤0.05% oxygen, but higher concentrations arrest growth by an unknown mechanism. Here we show that inactivation of a single gene, oxe (i.e., oxygen enabled) in B. fragilis allows for growth in concentrations as high as 2% oxygen while increasing the tolerance of this organism to room air. Known components of the oxidative stress response including the ahpC, kat, batA-E, and tpx genes were not individually important for microaerobic growth. However, a Δoxe strain scavenged H2O2 at a faster rate than WT, indicating that reactive oxygen species may play a critical role in limiting growth of this organism to low-oxygen environments. Clinical isolates of B. fragilis displayed a greater capacity for growth under microaerobic conditions than fecal isolates, with some encoding polymorphisms in oxe. Additionally, isolation of oxygen-enabled mutants of Bacteroides thetaiotaomicron suggests that Oxe may mediate growth arrest of other anaerobes in oxygenated environments.

Enzootic abortion in ewes (EAE) is caused by strains of Chlamydia psittaci which have the ability to invade and colonise the placenta of sheep. In an attempt to improve diagnostic methods for the detection of EAE, subtraction hybridisation was used to isolate unique fragments of the genome of an abortifacient strain (S26/3) of C. psittaci. One S26/3 strain-specific sequence identified was shown to encode a putative helicase which is repeated throughout the EAE genome. The labelled strain-specific helicase gene fragment was used in a dot-blot hybridisation test for the detection of EAE DNA in ovine placental samples. We report the identification of C. psittaci S26/3 strain-specific sequences with potential as diagnostic probes for the detection of EAE.

Abstract Enzootic abortion in ewes (EAE) is caused by strains of Chlamydia psittaci which have the ability to invade and colonise the placenta of sheep. In an attempt to improve diagnostic methods for the detection of EAE, subtraction hybridisation was used to isolate unique fragments of the genome of an abortifacient strain (S26/3) of C. psittaci. One S26/3 strain-specific sequence identified was shown to encode a putative helicase which is repeated throughout the EAE genome. The labelled strain-specific helicase gene fragment was used in a dot-blot hybridisation test for the detection of EAE DNA in ovine placental samples. We report the identification of C. psittaci S26/3 strain-specific sequences with potential as diagnostic probes for the detection of EAE.

The management of African (Loxodonta africana) and Asian (Elephas maximus) elephants in zoos involves a range of practices including feeding, exercise, training, and environmental enrichment. These practices are necessary to meet the elephants' nutritional, healthcare, and husbandry needs. However, these practices are not standardized, resulting in likely variation among zoos as well as differences in the way they are applied to individual elephants within a zoo. To characterize elephant management in North America, we collected survey data from zoos accredited by the Association of Zoos and Aquariums, developed 26 variables, generated population level descriptive statistics, and analyzed them to identify differences attributable to sex and species. Sixty-seven zoos submitted surveys describing the management of 224 elephants and the training experiences of 227 elephants. Asian elephants spent more time managed (defined as interacting directly with staff) than Africans (mean time managed: Asians = 56.9%; Africans = 48.6%; p<0.001), and managed time increased by 20.2% for every year of age for both species. Enrichment, feeding, and exercise programs were evaluated using diversity indices, with mean scores across zoos in the midrange for these measures. There were an average of 7.2 feedings every 24-hour period, with only 1.2 occurring during the nighttime. Feeding schedules were predictable at 47.5% of zoos. We also calculated the relative use of rewarding and aversive techniques employed during training interactions. The population median was seven on a scale from one (representing only aversive stimuli) to nine (representing only rewarding stimuli). The results of our study provide essential information for understanding management variation that could be relevant to welfare. Furthermore, the variables we created have been used in subsequent elephant welfare analyses.

Inactivating mutations in SMARCA4 ( BRG1 ), a key SWI/SNF chromatin remodelling gene, underlie small cell carcinoma of the ovary, hypercalcemic type (SCCOHT). To reveal its druggable vulnerabilities, we perform kinase-focused RNAi screens and uncover that SMARCA4-deficient SCCOHT cells are highly sensitive to the inhibition of cyclin-dependent kinase 4/6 (CDK4/6). SMARCA4 loss causes profound downregulation of cyclin D1, which limits CDK4/6 kinase activity in SCCOHT cells and leads to in vitro and in vivo susceptibility to CDK4/6 inhibitors. SCCOHT patient tumors are deficient in cyclin D1 yet retain the retinoblastoma-proficient/p16 INK4a -deficient profile associated with positive responses to CDK4/6 inhibitors. Thus, our findings indicate that CDK4/6 inhibitors, approved for a breast cancer subtype addicted to CDK4/6 activation, could be repurposed to treat SCCOHT. Moreover, our study suggests a novel paradigm whereby critically low oncogene levels, caused by loss of a driver tumor suppressor, may also be exploited therapeutically. Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is driven by SMARCA4 loss. Here the authors demonstrate that SCCOHT cells are highly sensitive to CDK4/6 inhibition and provide mechanistic insights, whereby this druggable vulnerability is driven by cyclin D1 deficiency induced by SMARCA4 loss.

Objectives To describe the number of hospital admissions for concussion at paediatric hospitals in the USA. To describe the use of imaging and medications for acute concussion paediatric patients. Design Cross-sectional study. Setting Children's hospitals participating in the Pediatric Health Information System in the USA during a 10-year period. Patients All emergency department (ED) visits and inpatient admissions with the primary diagnosis of concussion, defined as International Classification of Diseases, Ninth Revision, Clinical Modification codes for: (1) concussion, (2) postconcussion syndrome or (3) skull fracture without mention of intracranial injury with concussion. Main outcome measures The proportion of concussion patients who were hospitalised, underwent imaging or received medication, and the adjusted costs of visits for concussion. Results The number of ED visits for concussion increased between 2001 and 2010 (2126 (0.36% of all ED visits) vs 4967 (0.62% of all ED visits); p<0.001), while the number of admissions remained stable. Of ED visits for concussion, 59.9% received CT and 47.7% received medications or intravenous fluids. Non-narcotic analgesics were the most common medication administered. Adjusted costs of patient visits were significantly higher when imaging was obtained (US$695, IQR US$472–$1009, vs US$191, IQR US$114–$287). An ED visit with CT, however, cost less than a hospitalisation without CT (US$1907, IQR US$1292–$3770). Conclusions Although the number of ED patients diagnosed with concussion has increased, the number admitted has remained stable. Concussion patients at paediatric hospitals in the USA commonly undergo CT imaging and receive medication.

GNPS is an open-access community-curated analysis platform for sharing natural product mass spectrometry data that enables continuous, automatic reanalysis of deposited 'living' data sets. The potential of the diverse chemistries present in natural products (NP) for biotechnology and medicine remains untapped because NP databases are not searchable with raw data and the NP community has no way to share data other than in published papers. Although mass spectrometry (MS) techniques are well-suited to high-throughput characterization of NP, there is a pressing need for an infrastructure to enable sharing and curation of data. We present Global Natural Products Social Molecular Networking (GNPS; http://gnps.ucsd.edu ), an open-access knowledge base for community-wide organization and sharing of raw, processed or identified tandem mass (MS/MS) spectrometry data. In GNPS, crowdsourced curation of freely available community-wide reference MS libraries will underpin improved annotations. Data-driven social-networking should facilitate identification of spectra and foster collaborations. We also introduce the concept of 'living data' through continuous reanalysis of deposited data.