Observation of Gravitational Waves from a Binary Black Hole Merger

On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10(-21). It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410(-180)(+160)  Mpc corresponding to a redshift z=0.09(-0.04)(+0.03). In the source frame, the initial black hole masses are 36(-4)(+5)M⊙ and 29(-4)(+4)M⊙, and the final black hole mass is 62(-4)(+4)M⊙, with 3.0(-0.5)(+0.5)M⊙c(2) radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.

The risk for early-adulthood anxiety and depressive disorders in adolescents with anxiety and depressive disorders

BACKGROUND

Various studies find relationships among anxiety and depressive disorders of adolescence and adulthood. This study prospectively examines the magnitude of longitudinal associations between adolescent and adult anxiety or depressive disorders.

METHODS

An epidemiologically selected sample of 776 young people living in upstate New York received DSM-based psychiatric assessments in 1983, 1985, and 1992 using structured interviews. The magnitude of the association between adolescent and adult anxiety or depressive disorders was quantified using odds ratios generated from logistic regression analyses and from a set of latent Markov analyses. We focus on longitudinal associations among narrowly defined DSM anxiety or depressive disorders.

RESULTS

In simple logistic models, adolescent anxiety or depressive disorders predicted an approximate 2- to 3-fold increased risk for adulthood anxiety or depressive disorders. There was evidence of specificity in the course of simple and social phobia but less specificity in the course of other disorders. Results from the analyses using latent variables suggested that while most adolescent disorders were no longer present in young adulthood, most adult disorders were preceded by adolescent disorders.

CONCLUSIONS

An anxiety or depressive disorder during adolescence confers a strong risk for recurrent anxiety or depressive disorders during early adulthood. Most anxiety and depressive disorders in young adults may be preceded by anxiety or depression in adolescence.

Cutting edge: repurification of lipopolysaccharide eliminates signaling through both human and murine toll-like receptor 2

Toll-like receptor (TLR) 2 has recently been associated with cellular responses to numerous microbial products, including LPS and bacterial lipoproteins. However, many preparations of LPS contain low concentrations of highly bioactive contaminants described previously as "endotoxin protein," suggesting that these contaminants could be responsible for the TLR2-mediated signaling observed upon LPS stimulation. To test this hypothesis, commercial preparations of LPS were subjected to a modified phenol re-extraction protocol to eliminate endotoxin protein. While it did not influence the ability to stimulate cells from wild-type mice, repurification eliminated the ability of LPS to activate cells from C3H/HeJ (Lpsd) mice. Additionally, only cell lines transfected with human TLR4, but not human or murine TLR2, acquired responsiveness to both re-extracted LPS and to a protein-free, synthetic preparation of lipid A. These results suggest that neither human nor murine TLR2 plays a role in LPS signaling in the absence of contaminating endotoxin protein.

GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral

On August 17, 2017 at 12∶41:04 UTC the Advanced LIGO and Advanced Virgo gravitational-wave detectors made their first observation of a binary neutron star inspiral. The signal, GW170817, was detected with a combined signal-to-noise ratio of 32.4 and a false-alarm-rate estimate of less than one per 8.0×10^{4}  years. We infer the component masses of the binary to be between 0.86 and 2.26  M_{⊙}, in agreement with masses of known neutron stars. Restricting the component spins to the range inferred in binary neutron stars, we find the component masses to be in the range 1.17-1.60  M_{⊙}, with the total mass of the system 2.74_{-0.01}^{+0.04}M_{⊙}. The source was localized within a sky region of 28  deg^{2} (90% probability) and had a luminosity distance of 40_{-14}^{+8}  Mpc, the closest and most precisely localized gravitational-wave signal yet. The association with the γ-ray burst GRB 170817A, detected by Fermi-GBM 1.7 s after the coalescence, corroborates the hypothesis of a neutron star merger and provides the first direct evidence of a link between these mergers and short γ-ray bursts. Subsequent identification of transient counterparts across the electromagnetic spectrum in the same location further supports the interpretation of this event as a neutron star merger. This unprecedented joint gravitational and electromagnetic observation provides insight into astrophysics, dense matter, gravitation, and cosmology.

HER-2/neu gene amplification characterized by fluorescence in situ hybridization: poor prognosis in node-negative breast carcinomas

PURPOSE

The HER-2/neu gene codes for a membrane receptor protein that is homologous, but distinct from the epidermal growth factor receptor. This investigation was performed to validate fluorescence in situ hybridization (FISH) as a sensitive and specific method for assessing HER-2/neu gene amplification in archival tissue and to test whether this alteration is associated with poor prognosis.

MATERIALS AND METHODS

HER-2/neu gene amplification was determined by FISH in 140 archival breast cancers, previously characterized for gene amplification by Southern hybridization or dot-blot hybridization, and for gene expression by Northern hybridization, Western immunoblot, or immunohistochemistry. A separate cohort of 324 node-negative breast cancers was assessed for amplification by FISH to determine the utility of HER-2/neu gene amplification.

RESULTS

Relative to solid-matrix blotting procedures, FISH analysis of HER-2/neu gene amplification showed a sensitivity of 98% and a specificity of 100% in 140 breast cancers. Among patients treated by surgery only, the relative risks (relative hazard) of early recurrence (recurrent disease within 24 months of diagnosis), recurrent disease (at any time), and disease-related death were statistically significantly associated with amplification. The prognostic information contributed by HER-2/neu amplification was independent of the other markers studied.

CONCLUSION

FISH was an alternative technique for determining gene amplification and had some distinct advantages over Southern hybridization. Our results demonstrate that HER-2/neu gene amplification in the absence of adjuvant therapy is an independent predictor of poor clinical outcome and is a stronger discriminant than tumor size. Women with small tumors that had gene amplification were at increased risk of recurrence and disease-related death.

Phase III trial of gemcitabine plus tipifarnib compared with gemcitabine plus placebo in advanced pancreatic cancer

PURPOSE

To determine whether addition of the farnesyltransferase inhibitor tipifarnib (Zarnestra, R115777; Johnson and Johnson Pharmaceutical Research and Development, Beerse, Belgium) to standard gemcitabine therapy improves overall survival in advanced pancreatic cancer.

PATIENTS AND METHODS

This randomized, double-blind, placebo-controlled study compared gemcitabine + tipifarnib versus gemcitabine + placebo in patients with advanced pancreatic adenocarcinoma previously untreated with systemic therapy. Tipifarnib was given at 200 mg bid orally continuously; gemcitabine was given at 1,000 mg/m(2) intravenously weekly x 7 for 8 weeks, then weekly x 3 every 4 weeks. The primary end point was overall survival; secondary end points included 6-month and 1-year survival rates, progression-free survival, response rate, safety, and quality of life.

RESULTS

Six hundred eighty-eight patients were enrolled. Baseline characteristics were well balanced between the two treatment arms. No statistically significant differences in survival parameters were observed. The median overall survival for the experimental arm was 193 v 182 days for the control arm (P =.75); 6-month and 1-year survival rates were 53% and 27% v 49% and 24% for the control arm, respectively; median progression-free survival was 112 v 109 days for the control arm. Ten drug-related deaths were reported for the experimental arm and seven for the control arm. Neutropenia and thrombocytopenia grade > or = 3 were observed in 40% and 15% in the experimental arm versus 30% and 12% in the control arm. Incidences of nonhematologic adverse events were similar in two groups.

CONCLUSION

The combination of gemcitabine and tipifarnib has an acceptable toxicity profile but does not prolong overall survival in advanced pancreatic cancer compared with single-agent gemcitabine.

Genetically encoded reporters of protein kinase A activity reveal impact of substrate tethering

The complexity and specificity of many forms of signal transduction are widely suspected to require spatial microcompartmentation of protein kinase and phosphatase activities, yet current relevant imaging methods such as phosphorylation-specific antibodies or fluorescent peptide substrates require fixation or microinjection and lack temporal or spatial resolution. We present a genetically encoded fluorescent reporter for protein kinase A (PKA) consisting of fusions of cyan fluorescent protein, a phosphoamino acid binding domain (14-3-3tau), a consensus substrate for PKA, and yellow fluorescent protein. cAMP elevations cause 25-50% changes in the ratios of yellow to cyan emissions in live cells caused by phosphorylation-induced changes in fluorescence resonance energy transfer. The reporter response was accelerated by tethering to PKA holoenzyme and slowed by localization to the nucleus. We demonstrate that deliberate redistribution of a substrate or colocalizing a substrate and PKA can modulate its susceptibility to phosphorylation by the kinase. The successful design of a fluorescent reporter of PKA activity and its application for studying compartmentalized and dynamic modulation of kinases lays a foundation for studying targeting and compartmentation of PKA and other kinases and phosphatases.

Plant growth promoting rhizobacteria and endophytes accelerate phytoremediation of metalliferous soils

Technogenic activities (industrial-plastic, textiles, microelectronics, wood preservatives; mining-mine refuse, tailings, smelting; agrochemicals-chemical fertilizers, farm yard manure, pesticides; aerosols-pyrometallurgical and automobile exhausts; biosolids-sewage sludge, domestic waste; fly ash-coal combustion products) are the primary sources of heavy metal contamination and pollution in the environment in addition to geogenic sources. During the last two decades, bioremediation has emerged as a potential tool to clean up the metal-contaminated/polluted environment. Exclusively derived processes by plants alone (phytoremediation) are time-consuming. Further, high levels of pollutants pose toxicity to the remediating plants. This situation could be ameliorated and accelerated by exploring the partnership of plant-microbe, which would improve the plant growth by facilitating the sequestration of toxic heavy metals. Plants can bioconcentrate (phytoextraction) as well as bioimmobilize or inactivate (phytostabilization) toxic heavy metals through in situ rhizospheric processes. The mobility and bioavailability of heavy metal in the soil, particularly at the rhizosphere where root uptake or exclusion takes place, are critical factors that affect phytoextraction and phytostabilization. Developing new methods for either enhancing (phytoextraction) or reducing the bioavailability of metal contaminants in the rhizosphere (phytostabilization) as well as improving plant establishment, growth, and health could significantly speed up the process of bioremediation techniques. In this review, we have highlighted the role of plant growth promoting rhizo- and/or endophytic bacteria in accelerating phytoremediation derived benefits in extensive tables and elaborate schematic sketches.

Activating and dominant inactivating c-KIT catalytic domain mutations in distinct clinical forms of human mastocytosis

Human mastocytosis is characterized by increased mast cells. It usually occurs as a sporadic disease that is often transient and limited in children and persistent or progressive in adults. The c-KIT protooncogene encodes KIT, a tyrosine kinase that is the receptor for mast cell growth factor. Because mutated KIT can transform cells, we examined c-KIT in skin lesions of 22 patients with sporadic mastocytosis and 3 patients with familial mastocytosis. All patients with adult sporadic mastocytosis had somatic c-KIT mutations in codon 816 causing substitution of valine for aspartate and spontaneous activation of mast cell growth factor receptor (P = 0.0001). A subset of four pediatric onset cases with clinically unusual disease also had codon 816 activating mutations substituting valine, tyrosine, or phenylalanine for aspartate. Typical pediatric patients lacked 816 mutations, but limited sequencing showed three of six had a novel dominant inactivating mutation substituting lysine for glutamic acid in position 839, the site of a potential salt bridge that is highly conserved in receptor tyrosine kinases. No c-KIT mutations were found in the entire coding region of three patients with familial mastocytosis. We conclude that c-KIT somatic mutations substituting valine in position 816 of KIT are characteristic of sporadic adult mastocytosis and may cause this disease. Similar mutations causing activation of the mast cell growth factor receptor are found in children apparently at risk for extensive or persistent disease. In contrast, typical pediatric mastocytosis patients lack these mutations and may express inactivating c-KIT mutations. Familial mastocytosis, however, may occur in the absence of c-KIT coding mutations.

Hedgehog patterning activity: role of a lipophilic modification mediated by the carboxy-terminal autoprocessing domain

Autocatalytic processing mediated by the carboxyterminal domain of the hedgehog (hh) protein precursor (Hh) generates an amino-terminal product that accounts for all known signaling activity. The role of autoprocessing biogenesis of the hh signal has been unclear, since a truncated unprocessed protein lacking all carboxy-terminal domain sequences retains signaling activity. Here, we present evidence that the autoprocessing reaction proceeds via an internal thioester intermediate and results in a covalent modification that increases the hydrophobic character of the signaling domain and influences its spatial and subcellular distribution. We demonstrate that truncated unprocessed amino-terminal protein causes embryonic mispatterning, even when expression is localized to cells that normally express Hh, thus suggesting a role for autoprocessing in spatial regulation of hh signaling. This type of processing also appears to operate in the biogenesis of other novel secreted proteins.

BRCA1 inhibition of estrogen receptor signaling in transfected cells

Mutations of the breast cancer susceptibility gene BRCA1 confer increased risk for breast, ovarian, and prostatic cancers, but it is not clear why the mutations are associated with these particular tumor types. In transient transfection assays, BRCA1 was found to inhibit signaling by the ligand-activated estrogen receptor (ER-alpha) through the estrogen-responsive enhancer element and to block the transcriptional activation function AF-2 of ER-alpha. These results raise the possibility that wild-type BRCA1 suppresses estrogen-dependent transcriptional pathways related to mammary epithelial cell proliferation and that loss of this ability contributes to tumorigenesis.

Gender differences in social desirability and social approval bias in dietary self-report

Social desirability (the tendency to respond in such a way as to avoid criticism) and social approval (the tendency to seek praise) are two prominent response set biases evident in answers on structured questionnaires. These biases were tested by comparing nutrient intakes as estimated from a single 24-hour diet recall interview (24 HR) and a 7-day dietary recall (7DDR). Data were collected as part of the Worcester Area Trial for Counseling in Hyperlipidemia, a randomized, physician-delivered nutrition intervention trial for hypercholesterolemic patients conducted in Worcester, Massachusetts, from 1991 to 1995. Of the 1,278 total study subjects, 759 had complete data for analysis. Men overestimated their fat and energy intakes on the 7DDR as compared with the 24HR according to social approval: One unit increase in the social approval score was associated with an overestimate of 21.5 kcal/day in total energy intake and 1.2 g/day in total fat intake. Women, however, underestimated their dietary intakes on the 7DDR relative to the 24HR according to social desirability: One unit increase in the social desirability score was associated with an underestimate of 19.2 kcal/day in energy intake and 0.8 g/day in total fat. The results from the present study indicate that social desirability and social approval biases appear to vary by gender. Such biases may lead to misclassification of dietary exposure estimates resulting in a distortion in the perceived relation between health-related outcomes and exposure to specific foods or nutrients. Because these biases may vary according to the perceived demands of research subjects, it is important that they be assessed in a variety of potential research study populations.

A three-dimensional digital atlas database of the adult C57BL/6J mouse brain by magnetic resonance microscopy

A comprehensive three-dimensional digital atlas database of the C57BL/6J mouse brain was developed based on magnetic resonance microscopy images acquired on a 17.6-T superconducting magnet. By using both manual tracing and an atlas-based semi-automatic segmentation approach, T2-weighted magnetic resonance microscopy images of 10 adult male formalin-fixed, excised C57BL/6J mouse brains were segmented into 20 anatomical structures. These structures included the neocortex, hippocampus, amygdala, olfactory bulbs, basal forebrain and septum, caudate-putamen, globus pallidus, thalamus, hypothalamus, central gray, superior colliculi, inferior colliculi, the rest of midbrain, cerebellum, brainstem, corpus callosum/external capsule, internal capsule, anterior commissure, fimbria, and ventricles. The segmentation data were formatted and stored into a database containing three different atlas types: 10 single-specimen brain atlases, an average brain atlas and a probabilistic atlas. Additionally, quantitative group information, such as variations in structural volume, surface area, magnetic resonance microscopy image intensity and local geometry, were computed and stored as an integral part of the database. The database augments ongoing efforts with other high priority strains as defined by the Mouse Phenome Database focused on providing a quantitative framework for accurate mapping of functional, genetic and protein expression patterns acquired by a myriad of technologies and imaging modalities.

The unfolding tale of the unfolded protein response

Surface and secreted proteins are synthesized in the endoplasmic reticulum where they must fold and assemble before being transported. Changes in the ER that interfere with their proper maturation initiate the unfolded protein response pathway. New studies have filled in a missing link between the yeast and mammalian pathways.

Immune response in silico (IRIS): immune-specific genes identified from a compendium of microarray expression data

Immune cell-specific expression is one indication of the importance of a gene's role in the immune response. We have compiled a compendium of microarray expression data for virtually all human genes from six key immune cell types and their activated and differentiated states. Immune Response In Silico (IRIS) is a collection of genes that have been selected for specific expression in immune cells. The expression pattern of IRIS genes recapitulates the phylogeny of immune cells in terms of the lineages of their differentiation. Gene Ontology assignments for IRIS genes reveal significant involvement in inflammation and immunity. Genes encoding CD antigens, cytokines, integrins and many other gene families playing key roles in the immune response are highly represented. IRIS also includes proteins of unknown function and expressed sequence tags that may not represent genes. The predicted cellular localization of IRIS proteins is evenly distributed between cell surface and intracellular compartments, indicating that immune specificity is important at many points in the signaling pathways of the immune response. IRIS provides a resource for further investigation into the function of the immune system and immune diseases.

GW151226: Observation of Gravitational Waves from a 22-Solar-Mass Binary Black Hole Coalescence

We report the observation of a gravitational-wave signal produced by the coalescence of two stellar-mass black holes. The signal, GW151226, was observed by the twin detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) on December 26, 2015 at 03:38:53 UTC. The signal was initially identified within 70 s by an online matched-filter search targeting binary coalescences. Subsequent off-line analyses recovered GW151226 with a network signal-to-noise ratio of 13 and a significance greater than 5σ. The signal persisted in the LIGO frequency band for approximately 1 s, increasing in frequency and amplitude over about 55 cycles from 35 to 450 Hz, and reached a peak gravitational strain of 3.4_{-0.9}^{+0.7}×10^{-22}. The inferred source-frame initial black hole masses are 14.2_{-3.7}^{+8.3}M_{⊙} and 7.5_{-2.3}^{+2.3}M_{⊙}, and the final black hole mass is 20.8_{-1.7}^{+6.1}M_{⊙}. We find that at least one of the component black holes has spin greater than 0.2. This source is located at a luminosity distance of 440_{-190}^{+180}  Mpc corresponding to a redshift of 0.09_{-0.04}^{+0.03}. All uncertainties define a 90% credible interval. This second gravitational-wave observation provides improved constraints on stellar populations and on deviations from general relativity.

Histology of the gastroesophageal junction: an autopsy study

Current diagnostic criteria for reflux disease and Barrett's esophagus are based on the belief that the gastroesophageal junction normally contains 2 cm of cardiac mucosa composed of mucous glands devoid of parietal cells. This autopsy study disproves this belief. Even when the entire circumference of the gastroesophageal junction is examined, pure cardiac mucosa was completely absent in 56% of patients. All patients had oxyntocardiac mucosa, in which glands contained a mixture of mucous and parietal cells. Cardiac and oxyntocardiac mucosae were present only in part of the circumference of the junction in 50% of patients. The measured maximum length of cardiac plus oxyntocardiac mucosa was less than 0.5 cm in 76% of patients. There was a tendency for the presence and extent of cardiac mucosa to increase with age. Cardiac mucosa at the junction is therefore frequently absent, has considerable individual variation, is very small in extent when present, is commonly absent from some part of the circumference of the junction, and increases in prevalence and length with age. These characteristics of cardiac mucosa make it highly unlikely that it is a normal structure. We develop the hypothesis that cardiac mucosa represents an early histologic manifestation of gastroesophageal reflux.

Nutritional and socioeconomic factors in relation to prostate cancer mortality: a cross-national study

BACKGROUND

Large international variations in rates of prostate cancer incidence and mortality suggest that environmental factors have a strong influence on the development of this disease. The purpose of this study was to identify predictive variables for prostate cancer mortality in data from 59 countries.

METHODS

Data on prostate cancer mortality, food consumption, tobacco use, socioeconomic factors, reproductive factors, and health indicators were obtained from United Nations sources. Linear regression models were fit to these data. The influence of each variable fit in the regression models was assessed by multiplying the regression coefficient b by the 75th (X75) and 25th (X25) percentile values of the variable. The difference, bX75 - bX25, is the estimated effect of the variable across its interquartile range on mortality rates measured as deaths per 100000 males aged 45-74 years. Reported P values are two-sided.

RESULTS

Prostate cancer mortality was inversely associated with estimated consumption of cereals (bX75 - bX25 = -7.31 deaths; P = .001), nuts and oilseeds (bX75 - bX25 = -1.72 deaths; P = .003), and fish (bX75 - bX25 = -1.47 deaths; P = .001). In the 42 countries for which we had appropriate data, soy products were found to be significantly protective (P = .0001), with an effect size per kilocalorie at least four times as large as that of any other dietary factor. Besides variables related to diet, we observed an association between prostate cancer mortality rates and a composite of other health-related, sanitation, and economic variables (P = .003).

CONCLUSIONS

The specific food-related results from this study are consistent with previous information and support the current dietary guidelines and hypothesis that grains, cereals, and nuts are protective against prostate cancer. The findings also provide a rationale for future study of soy products in prostate cancer prevention trials.

A longitudinal study of students' depression at one medical school

PURPOSE

Using a standardized measure of depression at three assessment points, to examine depression in medical students during their training.

METHOD

Students entering the University of Massachusetts Medical School in the fall in 1987, 1988, and 1989 were mailed a recruitment letter and baseline questionnaire four weeks prior to the start of classes. Subsequent assessments took place in the middles of year 2 and year 4 and included only the students who had participated in the baseline assessment. The baseline assessment included the Center for Epidemiological Studies Depression (CES-D) scale, the Bortner Type A Behavior scale, the Spielberger Trait Anger scale, and the Spielberger Anger Expression scale. In addition, the baseline package included a rating of perceived stress, a demographics questionnaire, and a social-life survey. The follow-up assessments included the CES-D scale, the rating of perceived stress level, and the social-life survey. Analytic methods used were univariate descriptive statistics, correlation, and multiple-linear-regression analyses, two-sample t-tests, analysis of variance, and chi-square tests.

RESULTS

Of the initial pool of 300 students, 264 responded at the baseline assessment (88% response rate; 53% men); 171 of these participated in the year-2 assessment (65% response rate; 51% men), and 126 participated in the year-4 assessment (48% response rate; 48% men); a total of 99 students participated in all three assessments. CES-D scores > or =80th percentile were obtained for 18% of the entering students. This rose to 39% at year 2 and 31% at year 4 (p = .0001). No gender difference was found at baseline; however, the women experienced higher depression levels than did the men at year 2 (p = .004) and at year 4 (p = .04). Overall, gender and increases in perceived stress (from baseline to year 2) were significant predictors of increased CES-D scores (from baseline to year 2; p = .01 and p = .0001, respectively). For the women, increased perceived stress, angerin, and frequency of social contacts outside work/school were significant predictors of the magnitude of increases in CES-D scores (baseline to year 2; p = .0001, p = .02, and p = .03, respectively).

CONCLUSION

These preliminary data support the view that, upon entering medical school, students' emotional status resembles that of the general population. However, the rise in depression scores and their persistence over time suggest that emotional distress during medical school is chronic and persistent rather than episodic. Also, the women had more significant increases in depression scores than did the men.