SMT-738: a novel small-molecule inhibitor of bacterial lipoprotein transport targeting Enterobacteriaceae.

Carbapenem-resistant Enterobacteriaceae (CREs) are described by the Centers for Disease Control as an urgent threat, and there is a critical need for new therapeutic agents able to treat infections caused by these pathogens. Herein, we describe the microbiological profile, the mechanism f action, and the in vitro safety as well as the pharmacokinetic (PK)/PD profile of SMT-738, a small molecule belonging to a new chemical class. SMT-738 is active against Enterobacterales [including multi-drug-resistant Escherichia coli with 90% of isolates having a minimum inhibitory concentration (MIC90) of 1 µg/mL and Klebsiella pneumoniae 2 µg/mL] and inactive against a broad panel of Gram-negative and Gram-positive pathogens. SMT-738 displays rapid bactericidal activity (2-4 h) and has a low propensity for resistance development (less than ~10-9). Characterization of resistant mutants following exposure to SMT-738 identified mutations within the lipoprotein transport complex (LolCDE), a clinically unexploited and essential bacterial molecular target in Gram-negative bacteria. SMT-738 has a promising in vitro toxicology profile. Furthermore, PK studies demonstrated that when dosed intravenously, SMT-738 maintained exposure levels across infection sites (bloodstream/urinary tract/lung). Proof-of-concept studies across multiple murine in vivo infection models (bloodstream/pneumonia/urinary tract) demonstrated that SMT-738 significantly reduced the bacterial burden compared to baseline and vehicle control. SMT-738 represents a promising novel drug candidate being developed to address clinically challenging serious life-threatening infections caused by highly resistant Enterobacteriaceae including CRE.

Structure and density of silicon carbide to 1.5 TPa and implications for extrasolar planets.

There has been considerable recent interest in the high-pressure behavior of silicon carbide, a potential major constituent of carbon-rich exoplanets. In this work, the atomic-level structure of SiC was determined through in situ X-ray diffraction under laser-driven ramp compression up to 1.5 TPa; stresses more than seven times greater than previous static and shock data. Here we show that the B1-type structure persists over this stress range and we have constrained its equation of state (EOS). Using this data we have determined the first experimentally based mass-radius curves for a hypothetical pure SiC planet. Interior structure models are constructed for planets consisting of a SiC-rich mantle and iron-rich core. Carbide planets are found to be ~10% less dense than corresponding terrestrial planets.

Frequentist rules for regulatory approval of subgroups in phase III trials: A fresh look at an old problem.

BACKGROUND: The number of Phase III trials that include a biomarker in design and analysis has increased due to interest in personalised medicine. For genetic mutations and other predictive biomarkers, the trial sample comprises two subgroups, one of which, say B+ is known or suspected to achieve a larger treatment effect than the other B-. Despite treatment effect heterogeneity, trials often draw patients from both subgroups, since the lower responding B- subgroup may also gain benefit from the intervention. In this case, regulators/commissioners must decide what constitutes sufficient evidence to approve the drug in the B- population. METHODS AND RESULTS: Assuming trial analysis can be completed using generalised linear models, we define and evaluate three frequentist decision rules for approval. For rule one, the significance of the average treatment effect in B- should exceed a pre-defined minimum value, say ZB->L. For rule two, the data from the low-responding group B- should increase statistical significance. For rule three, the subgroup-treatment interaction should be non-significant, using type I error chosen to ensure that estimated difference between the two subgroup effects is acceptable. Rules are evaluated based on conditional power, given that there is an overall significant treatment effect. We show how different rules perform according to the distribution of patients across the two subgroups and when analyses include additional (stratification) covariates in the analysis, thereby conferring correlation between subgroup effects. CONCLUSIONS: When additional conditions are required for approval of a new treatment in a lower response subgroup, easily applied rules based on minimum effect sizes and relaxed interaction tests are available. Choice of rule is influenced by the proportion of patients sampled from the two subgroups but less so by the correlation between subgroup effects.

Suppression of circadian clock protein cryptochrome 2 promotes osteoarthritis.

OBJECTIVES: Abnormal chondrocyte gene expression promotes osteoarthritis (OA) pathogenesis. A previous RNA-sequencing study revealed that circadian rhythm pathway and expression of core clock gene cryptochrome 2 (CRY2) are dysregulated in human OA cartilage. Here we determined expression patterns and function CRY1 and CRY2. METHODS: CRY mRNA and protein expression was analyzed in normal and OA human and mouse cartilage. Mice with deletion of Cry1 or Cry2 were analyzed for severity of experimental OA and to determine genes and pathways that are regulated by Cry. RESULTS: In human OA cartilage, CRY2 but not CRY1 staining and mRNA expression was significantly decreased. Cry2 was also suppressed in mice with aging-related OA. Cry2 knock out (KO) but not Cry1 KO mice with experimental OA showed significantly increased severity of histopathological changes in cartilage, subchondral bone and synovium. In OA chondrocytes, the levels of CRY1 and CRY2 and the amplitude of circadian fluctuation were significantly lower. RNA-seq on knee articular cartilage of wild-type and Cry2 KO mice identified 53 differentially expressed genes, including known Cry2 target circadian genes Nr1d1, Nr1d2, Dbp and Tef. Pathway analysis that circadian rhythm and extracellular matrix remodeling were dysregulated in Cry2 KO mice. CONCLUSIONS: These results show an active role of the circadian clock in general, and of CRY2 in particular, in maintaining extracellular matrix (ECM) homeostasis in cartilage. This cell autonomous network of circadian rhythm genes is disrupted in OA chondrocytes. Targeting CRY2 has potential to correct abnormal gene expression patterns and reduce the severity of OA.

Alcohol and healthy ageing: a challenge for alcohol policy.

OBJECTIVES: This paper presents findings of a qualitative study of older people's use of alcohol during retirement and identifies ways that an improved understanding of older people's drinking can inform policy approaches to alcohol and active and healthy ageing. STUDY DESIGN: Qualitative semi-structured interviews conducted with a self-selecting sample of retired people. METHODS: Participants were recruited from three geographical locations in the West of Scotland. A quota sampling design was used to ensure a broad spread of participants in terms of socio-economic position, age and gender. In total 40 participants were interviewed and the data analysed thematically using Braun and Clarke's (2006) approach. RESULTS: Amongst those who used alcohol, it was most often framed in terms of pleasure, relaxation, socialising and as a way to mark the passage of time. Alcohol was often associated with social occasions and interactions both in private and in public spaces. There were also many examples of the use of imposed routines to limit alcohol use and of a decreasing volume of alcohol being consumed as participants aged. This suggests that older people are often active in constructing what they regard as 'healthier' routines around alcohol use. However, processes and circumstances associated with ageing can lead to risk of social isolation and/or increased alcohol consumption. Such processes include retirement from paid work and other 'biographical disruptions' such as caring for a partner, bereavement and/or loss of social networks. CONCLUSIONS: These findings highlight processes that can result in changes in drinking habits and routines. Whilst these processes can be associated with a reduction or cessation of alcohol use as people age, they can also be associated with increased risk of harmful alcohol consumption. Fractured or disrupted routines, particularly those associated with bereavement or the burden of caring responsibilities, through increasing the risk of loneliness and isolation, can construct increased risk of harmful alcohol consumption. These findings reframe the pathway of risk between ageing and alcohol-related harm by highlighting the vulnerability to harmful drinking practices brought by fracture or sudden change of routine. The findings point to a role for public health in supporting the reconstruction of routines that provide structure and meaning and can be used to actively manage the benefits and harms associated with drinking.

High-pressure phase transition in Y3Fe5O12.

Yttrium iron garnet (YIG, Y3Fe5O12) was examined up to 74 GPa and 1800 K using synchrotron x-ray diffraction in a diamond anvil cell. At room temperature, YIG remained in the garnet phase until abrupt amorphization occurred at 51 GPa, consistent with earlier studies. Upon laser heating up to 1800 K, the material transformed to a single-phase orthorhombic GdFeO3-type perovskite of composition (Y(0.75)Fe(0.25))FeO3. No evidence of decomposition of the sample was observed. Both the room-temperature amorphization and high-temperature transformation to the perovskite structure are consistent with the behaviour of other rare earth oxide garnets. The perovskite sample was compressed between 28-74 GPa with annealing to 1450-1650 K every 3-5 GPa. Between 46 and 50 GPa, a 6.8% volume discontinuity was observed without any accompanying change in the number or intensity of diffraction peaks. This is indicative of a high-spin to low-spin electronic transition in Fe(3+), likely in the octahedrally coordinated B-site of the perovskite. The volume change of the inferred spin transition is consistent with those observed in other rare earth ferric iron perovskites at high pressures.

Major cost savings associated with biologic dose reduction in patients with inflammatory arthritis.

The purpose of this study was to explore whether patients with Inflammatory Arthritis (IA) (Rheumatoid Arthritis (RA), Psoriatic Arthritis (PsA) or Ankylosing Spondylitis (AS)) would remain in remission following a reduction in biologic dosing frequency and to calculate the cost savings associated with dose reduction. This prospective non-blinded non-randomised study commenced in 2010. Patients with Inflammatory Arthritis being treated with a biologic agent were screened for disease activity. A cohort of those in remission according to standardized disease activity indices (DAS28 < 2.6, BASDAI < 4) was offered a reduction in dosing frequency of two commonly used biologic therapies (etanercept 50 mg once per fortnight instead of weekly, adalimumab 40 mg once per month instead of fortnightly). Patients were assessed for disease activity at 3, 6, 12, 18 and 24 months following reduction in dosing frequency. Cost saving was calculated. 79 patients with inflammatory arthritis in remission were recruited. 57% had rheumatoid arthritis (n = 45), 13% psoriatic arthritis (n = 10) and 30% ankylosing spondylitis (n = 24). 57% (n = 45) were taking etanercept and 43% (n = 34) adalimumab. The percentage of patients in remission at 24 months was 56% (n = 44). This resulted in an actual saving to the state of approximately 600,000 euro over two years. This study demonstrates the reduction in biologic dosing frequency is feasible in Inflammatory Arthritis. There was a considerable cost saving at two years. The potential for major cost savings in biologic usage should be pursued further.

Comprehensive assessment of alcohol-related brain damage (ARBD): gap or chasm in the evidence?

ACCESSIBLE SUMMARY: Alcohol-related brain damage (ARBD) causes a broad range of both neurological and neurocognitive impairment. Mental health nurses are required to provide programmes designed to facilitate individuals with chronic alcohol dependency to radically change their drinking behaviour, invariably with an abstinence focus. No evidence that related to the nutritional and physical intervention needs of this group was found. Most instruments used to access domains relevant to ARBD in terms of providing a comprehensive assessment have not been validated in this group. Alcohol-related brain damage (ARBD) is primarily caused by chronic alcohol misuse and thiamine deficiency, and results in a broad range of impairments. Despite the increasing incidence of ARBD in the UK in recent decades, it is currently underdiagnosed, managed inappropriately and treated inadequately. Moreover, information about assessments for individuals with ARBD is currently absent from clinical guidelines and policy documents. The aim of this paper was to review the evidence relating to the neurological, neuropsychological, psychosocial, physical and nutritional assessment of individuals with ARBD to identify appropriate assessment tools that could be used to measure and monitor the impact of ARBD over time. A systematic online database search revealed a total of 160 separate references, 133 of which were rejected and two of which could not be accessed. Twenty-five papers were included in the review, including six neuroimaging studies, 17 neuropsychological studies and two studies using psychosocial methods of assessment. A lack of evidence for nutritional and physical assessment of individuals with ARBD was found. The review findings are inconclusive; most instruments currently used in ARBD research have not specifically been validated for use within an ARBD context. Further research is required to identify comprehensive methods of ARBD assessment.

Ramp compression of diamond to five terapascals.

The recent discovery of more than a thousand planets outside our Solar System, together with the significant push to achieve inertially confined fusion in the laboratory, has prompted a renewed interest in how dense matter behaves at millions to billions of atmospheres of pressure. The theoretical description of such electron-degenerate matter has matured since the early quantum statistical model of Thomas and Fermi, and now suggests that new complexities can emerge at pressures where core electrons (not only valence electrons) influence the structure and bonding of matter. Recent developments in shock-free dynamic (ramp) compression now allow laboratory access to this dense matter regime. Here we describe ramp-compression measurements for diamond, achieving 3.7-fold compression at a peak pressure of 5 terapascals (equivalent to 50 million atmospheres). These equation-of-state data can now be compared to first-principles density functional calculations and theories long used to describe matter present in the interiors of giant planets, in stars, and in inertial-confinement fusion experiments. Our data also provide new constraints on mass-radius relationships for carbon-rich planets.

Comparative responses to endocrine disrupting compounds in early life stages of Atlantic salmon, Salmo salar.

Atlantic salmon (Salmo salar) are endangered anadromous fish that may be exposed to feminizing endocrine disrupting compounds (EDCs) during early development, potentially altering physiological capacities, survival and fitness. To assess differential life stage sensitivity to common EDCs, we carried out short-term (4 day) exposures using three doses each of 17 α-ethinylestradiol (EE2), 17 ß-estradiol (E2), and nonylphenol (NP) on four early life stages; embryos, yolk-sac larvae, feeding fry and 1 year old smolts. Differential response was compared using vitellogenin (Vtg, a precursor egg protein) gene transcription. Smolts were also examined for impacts on plasma Vtg, cortisol, thyroid hormones (T4/T3) and hepatosomatic index (HSI). Compound-related mortality was not observed in any life stage, but Vtg mRNA was elevated in a dose-dependent manner in yolk-sac larvae, fry and smolts but not in embryos. The estrogens EE2 and E2 were consistently stronger inducers of Vtg than NP. Embryos responded significantly to the highest concentration of EE2 only, while older life stages responded to the highest doses of all three compounds, as well as intermediate doses of EE2 and E2. Maximal transcription was greater for fry among the three earliest life stages, suggesting fry may be the most responsive life stage in early development. Smolt plasma Vtg was also significantly increased, and this response was observed at lower doses of each compound than was detected by gene transcription suggesting plasma Vtg is a more sensitive indicator at this life stage. HSI was increased at the highest doses of EE2 and E2, and plasma T3 was decreased at the highest dose of EE2. Our results indicate that all life stages are potentially sensitive to endocrine disruption by estrogenic compounds and that physiological responses were altered over a short window of exposure, indicating the potential for these compounds to impact fish in the wild.

A comparison of the quality of life of vulnerable young males with severe emotional and behaviour difficulties in a residential setting and young males in mainstream schooling.

One hundred and seventy-four males completed a quality of life (QoL) assessment utilizing, a generic paediatric quality of life inventory (PedsQL) and the short form (36) health survey (SF36). The adolescents aged 13-16 years were in a Scottish Centre for young males with social, emotional, behavioural and educational problems. To identify similarities and differences, a comparison group (n = 110) of males in the third and fourth year in a mainstream secondary school were also administered the PedsQL and the SF36 self-rating scales. The effectiveness of the PedsQL and the SF36 for assessing QoL for adolescent males was investigated. There were significant differences between the groups in the Centre and between the Centre groups and the comparison group in terms of their QoL. The results between the groups were found in the PedsQL subscales 'physical functioning' where secure > comparison (P = 0.04); secure > residential (P = 0.008); and PedsQL subscale 'social functioning' day > comparison (P = 0.026); secure > comparison (P = 0.037). SF36 subscales 'role physical functioning' secure > residential (P < 0.001); day > residential (P < 0.001). SF36 'role mental functioning' day > residential (P = 0.001). This study provides a unique insight into the complex dimensions influencing the QoL of this specific group of young people.

Assessment of the quality of life of vulnerable young males with severe emotional and behaviour difficulties in a residential setting.

Sixty-four looked after and accommodated males aged 13-16 had an assessment of their quality of life using Paediatric Quality of Life Inventory (PedsQL) and Quality of Life in Care (QOLIC). The participants were from a Scottish residential centre for young people with severe emotional and behavioural difficulties. The total sample of 64 participants consists of two distinct groups: residential group (n = 33) and a secure care group (n = 31). Over 3 observations the aim of the study was to identify similarities and differences between the groups and to establish the sensitivity of the PedsQL and the PedsQL in care module (QOLIC) as a measurement instrument for Quality of Life (QoL) in adolescent males. Overall there was a nonsignificant increase in the quality of life of these young people at the centre as measured by PedsQL and QOLIC over 3 observations. No significant differences were detected in the quality of life scores between the two groups using the QOLIC.

Trypanosoma cruzi discrete typing units in Chagas disease patients from endemic and non-endemic regions of Argentina.

Genetic diversity of Trypanosoma cruzi may play a role in pathogenesis of Chagas disease forms. Natural populations are classified into 6 Discrete Typing Units (DTUs) Tc I-VI with taxonomical status. This study aimed to identify T. cruzi DTUs in bloodstream and tissue samples of Argentinean patients with Chagas disease. PCR-based strategies allowed DTU identification in 256 clinical samples from 239 Argentinean patients. Tc V prevailed in blood from both asymptomatic and symptomatic cases and Tc I was more frequent in bloodstream, cardiac tissues and chagoma samples from immunosuppressed patients. Tc II and VI were identified in a minority of cases, while Tc III and Tc IV were not detected in the studied population. Interestingly, Tc I and Tc II/VI sequences were amplified from the same skin biopsy slice from a kidney transplant patient suffering Chagas disease reactivation. Further data also revealed the occurrence of mixed DTU populations in the human chronic infection. In conclusion, our findings provide evidence of the complexity of the dynamics of T. cruzi diversity in the natural history of human Chagas disease and allege the pathogenic role of DTUs I, II, V and VI in the studied population.

Interactions between hypoxia and sewage-derived contaminants on gene expression in fish embryos.

Fish embryos were used to evaluate the interaction among common environmental and chemical stressors found in urban coastal environments, namely hypoxia, aryl hydrocarbon receptor (AhR) agonists, and estrogenic compounds. At the molecular level, the systems responding to these stressors share common response factors, and evidence exists for cross-talk between them. Biomarkers of exposure to these stressors, cytochrome P4501a (Cyp1a), estrogen receptor alpha (ERα), brain cytochrome P450 aromatase (Cyp19a2 or AromB), and hypoxia inducible factor 1 alpha (Hif-1α) mRNA expression were examined using qRT-PCR simultaneously in embryos of two well studied species, the Atlantic killifish, Fundulus heteroclitus, and the zebrafish Danio rerio. Embryos of both species were exposed to the model Cyp1a inducer ß-naphthoflavone (BNF) or 17-ß estradiol (E2) under either normoxic or hypoxic (5% oxygen atmosphere) conditions and harvested prior to hatch at 9 days post fertilization (dpf) for the killifish, and 48h post fertilization (hpf) for the zebrafish. BNF significantly induced Cyp1a expression in embryos of both species with killifish embryos being more responsive (700-fold>control) than zebrafish embryos (7-100-fold>control). AromB was also significantly influenced by treatment, but to a lesser extent, with mean expression levels increased by less than two-fold over control values in response to E2, and in one case upregulated by BNF. ERα and Hif-1α were constitutively expressed in embryos of both species, but expression was unaffected by exposure to either BNF or E2. Hypoxic conditions downregulated AromB expression strongly in killifish but not in zebrafish embryos. The impact of hypoxia on expression of other genes in either species was inconsistent, although an interactive effect between hypoxia and BNF on several of the genes evaluated was observed. These data are the first to examine expression patterns of these important environmental response genes together in embryos of two important model fish species. The results support the use of Cyp1a expression as a biomarker of AhR agonists in fish embryos, and indicate that AromB may be more responsive than ERα to estrogenic chemicals at this stage in development. Hif-1α expression was not found to be a good biomarker of hypoxic exposure in either killifish or zebrafish embryos. The interaction observed between BNF and co-exposure to hypoxia warrants further investigation. Finally killifish embryos are generally more sensitive than zebrafish embryos at this stage of development supporting their use in environmental assessments.

The National Ignition Facility neutron time-of-flight system and its initial performance (invited).

The National Ignition Facility (NIF) successfully completed its first inertial confinement fusion (ICF) campaign in 2009. A neutron time-of-flight (nTOF) system was part of the nuclear diagnostics used in this campaign. The nTOF technique has been used for decades on ICF facilities to infer the ion temperature of hot deuterium (D(2)) and deuterium-tritium (DT) plasmas based on the temporal Doppler broadening of the primary neutron peak. Once calibrated for absolute neutron sensitivity, the nTOF detectors can be used to measure the yield with high accuracy. The NIF nTOF system is designed to measure neutron yield and ion temperature over 11 orders of magnitude (from 10(8) to 10(19)), neutron bang time in DT implosions between 10(12) and 10(16), and to infer areal density for DT yields above 10(12). During the 2009 campaign, the three most sensitive neutron time-of-flight detectors were installed and used to measure the primary neutron yield and ion temperature from 25 high-convergence implosions using D(2) fuel. The OMEGA yield calibration of these detectors was successfully transferred to the NIF.

Are chronic fatigue syndrome and fibromyalgia the same? Implications for the provision of appropriate mental health intervention.

Chronic fatigue syndrome and fibromyalgia represent distinct diagnostic entities within both the clinical and research literature. A common feature of both presentations is that they are often accompanied by a significant mental health burden. A further salient feature of both conditions is that there is no consistent consensus on aetiology. Evaluation of the features of each disorder seems to present a convincing case that both disorders may indeed have a common aetiology and further, the possibility exists that chronic fatigue syndrome and fibromyalgia represent the same underlying disorder. Paradoxically, given this possibility it is remarkable that both patient groups are treated clinically with considerably different approaches to care and management. Mental health practitioners will come into contact with both groups of patients when support for the psychological consequences of diagnosis are necessary; however, many practitioners will be unaware of the debate regarding the aetiological ambiguities surrounding these presentations. The purpose of this review is to highlight the above issues in order to both facilitate awareness of the current aetiological/diagnostic impasse and facilitate provision of optimum mental health support.

Motor scores on the functional independence measure after pediatric spinal cord injury.

STUDY DESIGN: Retrospective descriptive analysis. OBJECTIVES: The purpose of this study was to report the functional ability of children with spinal cord injury (SCI) as recorded on motor items of the functional independence measure (FIM) and to examine the factors associated with FIM motor admission and post-discharge gain scores. METHODS: Scores on FIM motor items were analyzed from 941 children (age range: 0-21 years; mean: 13 years 4 months; s.d.: 4 years 8 months) admitted in acute-to-chronic time periods post-SCI to Shriners Hospitals for Children (USA). FIM motor scores at admission and gains at discharge were examined along with neurological level, completeness of injury, age, etiology of injury, and length of time between injury and admission and admission and discharge. RESULTS: The FIM motor scores at admission were negatively correlated with age, neurological level and completeness of injury. Gain in FIM motor scores was significant across neurological levels, and was associated with lower admission FIM motor scores, lower neurological level, incomplete injury, traumatic injury and less time between injury and admission. CONCLUSIONS: The motor function of children after pediatric SCI depends on neurological level and completeness of injury, among other factors. FIM motor scores can improve with intervention even several years after the injury.

Real-time PCR strategy for rapid discrimination among main lymnaeid species from Argentina.

Snails of the Family Lymnaeidae act as an intermediate hosts of Fasciola hepatica worldwide. The taxonomy of lymnaeid species is relevant for epidemiological studies and molecular strategies are increasingly used for that purpose. This work presents the first report of a real-time PCR approach used to identify the most important lymnaeid species in the Southern Cone of South America. Species discrimination is based on the sequence polymorphism located within the helix E10-1 of the variable region V2 of the 18S rRNA genes, which yields amplicons with clearly different melting temperatures. This procedure minimises the risk of carry-over contamination because it does not require post-PCR manipulations, and the whole protocol can be completed in less than 4h with a single snail foot as starting material. This method was successfully carried out in a blind study that included a panel of 20 Galba truncatula, 5 Lymnaea viatrix, 5 Lymnaea diaphana and 5 Pseudosuccinea columella specimens from different endemic areas for fasciolosis. This molecular approach constitutes a key laboratory tool complementing ecological studies that ultimately will promote more efficient control strategies.

Tests and calibration of NIF neutron time of flight detectors.

The National Ignition Facility (NIF) neutron time of flight (NTOF) diagnostic will measure neutron yield and ion temperature in all NIF campaigns in DD, DT, and THD(*) implosions. The NIF NTOF diagnostic is designed to measure neutron yield from 1x10(9) to 2x10(19). The NTOF consists of several detectors of varying sensitivity located on the NIF at about 5 and 20 m from the target. Production, testing, and calibration of the NIF NTOF detectors have begun at the Laboratory for Laser Energetics (LLE). Operational tests of the NTOF detectors were performed on several facilities including the OMEGA laser at LLE and the Titan laser at Lawrence Livermore National Laboratory. Neutron calibrations were carried out on the OMEGA laser. Results of the NTOF detector tests and calibration will be presented.