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.

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.

Intracellular cleavage of Notch leads to a heterodimeric receptor on the plasma membrane

Previous models for signal transduction via the Notch pathway have depicted the full-length Notch receptor expressed at the cell surface. We present evidence demonstrating that the Notch receptor on the plasma membrane is cleaved. This cleavage is an evolutionarily conserved, general property of Notch and occurs in the trans-Golgi network as the receptor traffics toward the plasma membrane. Although full-length Notch is detectable in the cell, it does not reach the surface. Cleavage results in a C-terminal fragment, N(TM), that appears to be cleaved N-terminal to the transmembrane domain, and an N-terminal fragment, N(EC), that contains most of the extracellular region. We provide evidence that these fragments are tethered together on the plasma membrane by a link that is sensitive to reducing conditions, forming a heterodimeric receptor.

Processing of the notch ligand delta by the metalloprotease Kuzbanian

Signaling by the Notch surface receptor controls cell fate determination in a broad spectrum of tissues. This signaling is triggered by the interaction of the Notch protein with what, so far, have been thought to be transmembrane ligands expressed on adjacent cells. Here biochemical and genetic analyses show that the ligand Delta is cleaved on the surface, releasing an extracellular fragment capable of binding to Notch and acting as an agonist of Notch activity. The ADAM disintegrin metalloprotease Kuzbanian is required for this processing event. These observations raise the possibility that Notch signaling in vivo is modulated by soluble forms of the Notch ligands.

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.

GW170104: Observation of a 50-Solar-Mass Binary Black Hole Coalescence at Redshift 0.2

We describe the observation of GW170104, a gravitational-wave signal produced by the coalescence of a pair of stellar-mass black holes. The signal was measured on January 4, 2017 at 10∶11:58.6 UTC by the twin advanced detectors of the Laser Interferometer Gravitational-Wave Observatory during their second observing run, with a network signal-to-noise ratio of 13 and a false alarm rate less than 1 in 70 000 years. The inferred component black hole masses are 31.2_{-6.0}^{+8.4}M_{⊙} and 19.4_{-5.9}^{+5.3}M_{⊙} (at the 90% credible level). The black hole spins are best constrained through measurement of the effective inspiral spin parameter, a mass-weighted combination of the spin components perpendicular to the orbital plane, χ_{eff}=-0.12_{-0.30}^{+0.21}. This result implies that spin configurations with both component spins positively aligned with the orbital angular momentum are disfavored. The source luminosity distance is 880_{-390}^{+450}  Mpc corresponding to a redshift of z=0.18_{-0.07}^{+0.08}. We constrain the magnitude of modifications to the gravitational-wave dispersion relation and perform null tests of general relativity. Assuming that gravitons are dispersed in vacuum like massive particles, we bound the graviton mass to m_{g}≤7.7×10^{-23}  eV/c^{2}. In all cases, we find that GW170104 is consistent with general relativity.

Cloning and characterization of a novel member of the transforming growth factor-beta/bone morphogenetic protein family

Members of the transforming growth factor-beta (TGF-beta) superfamily of growth and differentiation factors have been identified in a wide variety of organisms, ranging from invertebrates to mammals. Bone morphogenetic proteins (BMPs) constitute a subgroup of proteins belonging to the TGF-beta superfamily. BMPs were initially identified by their ability to induce endochondral bone formation at ectopic sites, suggesting a critical role for this family in development and regeneration of the skeleton. They are also expressed at a variety of nonskeletal sites during development, suggesting possible extraskeletal roles for these proteins. We cloned a novel member of the BMP family that is expressed at high levels in the placenta and the prostate and that we have designated as prostate-derived factor (PDF). Based on cDNA sequence analysis, the predicted PDF protein contains two cysteines in addition to the seven conserved cysteines that are the hallmark of the members of the TGF-beta superfamily. In addition, Northern blot hybridization to poly(A)+ RNA showed low levels of expression in the kidney and pancreas. We further characterized the expression of this member of the BMP family by in situ hybridization and immunohistochemistry. These results show high expression in the terminal villae of the placenta. The expression of the protein as visualized by immunohistochemistry shows an expression pattern identical to that of the message in the terminal villae of the placenta. In day 18 rat embryos, protein expression was also seen in the skin and in the cartilaginous tissue of developing skeleton. Orchidectomy and dihydrotestosterone treatment of rats revealed that PDF expression is regulated by androgens in the prostate. In addition, subcutaneous implantation of recombinant PDF induced cartilage formation and the early stages of endochondral bone formation. These data indicate that PDF has a functional relationship to the BMPs.

Calcium influx induces neurite growth through a Src-Ras signaling cassette

We find that calcium influx through voltage-dependent calcium channels causes extensive neurite outgrowth in PC12 cells. The calcium signal transduction pathway promoting neurite outgrowth causes the rapid activation of protein tyrosine kinases, which include Src. Protein tyrosine phosphorylation results in the formation of an Shc/Grb2 complex, leading to Ras activation, MAP kinase activation, and the subsequent induction of the immediate early gene NGFI-A. Protein tyrosine phosphorylation, gene induction, and neurite outgrowth are inhibited by the expression of dominant negative forms of both Src and Ras, indicating a requirement for both proto-oncoproteins in calcium signaling. Our results suggest that a signaling cassette which includes Src and Ras is likely to underlie a broad range of calcium of actions in the nervous system.

Factors controlling the efficiency of cationic lipid-mediated transfection in vivo via intravenous administration

The factors controlling the transfection efficiency of cationic lipid carrier systems following intravenous administration are poorly understood. Using N-[1-(2,3-dioleoyloxy)propyl]-N,N,N-trimethylammonium chloride (DOTMA) combined with Tween 80 as a carrier system and cDNA of luciferase or beta-galactosidase gene as a reporter, we investigated the importance of DOTMA to DNA ratio and the ratio of DOTMA to Tween 80 in the lipid formulation in determining the site and level of transgene expression following intravenous administration. The data show that all of the internal organs, including lung, liver, spleen, heart and kidneys, expressed the transgene upon systemic administration into animals with 25 micrograms of plasmid DNA when complexed with DOTMA-Tween 80 lipid formulation. The transfection efficiency was dependent on both DOTMA to DNA, and DOTMA to Tween 80 ratios. Among the organs examined, the lung appeared to be more transfectable than other organs. A better transfection activity was obtained with higher DOTMA to DNA and DOTMA to Tween 80 ratios. Time-response curve shows that gene expression was transient with a maximal level between 10 and 24 h after injection. Results from tissue distribution studies with 125I-labeled plasmid DNA and Southern analysis suggest that the transient expression is the result of the loss of transgene from the transfected cells. These results suggest that cationic lipid-based delivery systems can be efficient for gene delivery if the composition of the DNA-lipid complexes is properly controlled.

GW170817: Measurements of Neutron Star Radii and Equation of State

On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Here, we expand upon previous analyses by working under the hypothesis that both bodies were neutron stars that are described by the same equation of state and have spins within the range observed in Galactic binary neutron stars. Our analysis employs two methods: the use of equation-of-state-insensitive relations between various macroscopic properties of the neutron stars and the use of an efficient parametrization of the defining function p(ρ) of the equation of state itself. From the LIGO and Virgo data alone and the first method, we measure the two neutron star radii as R_{1}=10.8_{-1.7}^{+2.0}  km for the heavier star and R_{2}=10.7_{-1.5}^{+2.1}  km for the lighter star at the 90% credible level. If we additionally require that the equation of state supports neutron stars with masses larger than 1.97  M_{⊙} as required from electromagnetic observations and employ the equation-of-state parametrization, we further constrain R_{1}=11.9_{-1.4}^{+1.4}  km and R_{2}=11.9_{-1.4}^{+1.4}  km at the 90% credible level. Finally, we obtain constraints on p(ρ) at supranuclear densities, with pressure at twice nuclear saturation density measured at 3.5_{-1.7}^{+2.7}×10^{34}  dyn cm^{-2} at the 90% level.

Regulation of an endogenous locus using a panel of designed zinc finger proteins targeted to accessible chromatin regions. Activation of vascular endothelial growth factor A

We have mapped conserved regions of enhanced DNase I accessibility within the endogenous chromosomal locus of vascular endothelial growth factor A (VEGF-A). Synthetic zinc finger protein (ZFP) transcription factors were designed to target DNA sequences contained within the DNase I-hypersensitive regions. These ZFPs, when fused to either VP16 or p65 transcriptional activation domains, were able to activate expression of the VEGF-A gene as assayed by mRNA accumulation and VEGF-A protein secretion through a range exceeding that induced by hypoxic stress. Importantly, multiple splice variants of VEGF-A mRNA with defined physiological functions were induced by a single engineered ZFP transcription factor. We present evidence for an enhanced activation of VEGF-A gene transcription by ZFP transcription factors fused to VP16 and p65 targeted to two distinct chromosomal sites >500 base pairs upstream or downstream of the transcription start site. Our strategy provides a novel approach for dissecting the requirements for gene regulation at a distance without altering the DNA sequence of the endogenous target locus.

Tests of General Relativity with GW150914

The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant's mass and spin, as determined from the low-frequency (inspiral) and high-frequency (postinspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasinormal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parametrized general-relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a 90%-confidence lower bound of 10^{13}  km. In conclusion, within our statistical uncertainties, we find no evidence for violations of general relativity in the genuinely strong-field regime of gravity.

GW170814: A Three-Detector Observation of Gravitational Waves from a Binary Black Hole Coalescence

On August 14, 2017 at 10∶30:43 UTC, the Advanced Virgo detector and the two Advanced LIGO detectors coherently observed a transient gravitational-wave signal produced by the coalescence of two stellar mass black holes, with a false-alarm rate of ≲1 in 27 000 years. The signal was observed with a three-detector network matched-filter signal-to-noise ratio of 18. The inferred masses of the initial black holes are 30.5_{-3.0}^{+5.7}M_{⊙} and 25.3_{-4.2}^{+2.8}M_{⊙} (at the 90% credible level). The luminosity distance of the source is 540_{-210}^{+130}  Mpc, corresponding to a redshift of z=0.11_{-0.04}^{+0.03}. A network of three detectors improves the sky localization of the source, reducing the area of the 90% credible region from 1160   deg^{2} using only the two LIGO detectors to 60  deg^{2} using all three detectors. For the first time, we can test the nature of gravitational-wave polarizations from the antenna response of the LIGO-Virgo network, thus enabling a new class of phenomenological tests of gravity.

Parathyroid hormone is more effective than estrogen or bisphosphonates for restoration of lost bone mass in ovariectomized rats

The study was designed to compare the therapeutic efficacy of estrogen, the bisphosphonate risedronate (NE-58095), and PTH for restoration of lost bone mass in osteopenic, ovariectomized (OVX) rats. In addition, the skeletal effects of these single treatments were compared to those of concurrent treatments with PTH + estrogen or PTH + NE-58095. OVX rats were untreated for the first 4 weeks postovariectomy to allow for the development of moderate tibial osteopenia. These animals were then subjected to the various treatments for periods of 5, 10, and 15 weeks. Their proximal tibiae were processed undecalcified for quantitative bone histomorphometry. Treatment of osteopenic OVX rats with estrogen or NE-58095 alone depressed bone turnover and prevented additional cancellous bone loss from occurring during the treatment period. However, these therapeutic agents failed to restore lost bone in OVX rats to control levels. In contrast, OVX rats treated with PTH alone exhibited a marked stimulation of bone formation which resulted in augmentation of cancellous bone mass to a level 2-fold greater than that of vehicle-treated control rats. Concurrent treatment of OVX rats with PTH + estrogen as well as PTH + NE-58095 also effectively reversed cancellous osteopenia in OVX rats, but did not appear to be more beneficial to the estrogen-deplete skeleton than treatment with PTH alone. The results indicate that PTH is a powerful stimulator of bone formation and completely restores lost cancellous bone in osteopenic OVX rats. Furthermore, the bone anabolic effects of PTH are much more pronounced than those of estrogen or bisphosphonates. These findings in an animal model of estrogen depletion provide support for PTH as a potentially effective treatment for oophorectomized and postmenopausal women with established osteoporosis.

Synthetic zinc finger transcription factor action at an endogenous chromosomal site. Activation of the human erythropoietin gene

We have targeted the activation of an endogenous chromosomal locus including the human erythropoietin gene using synthetic transcription factors. These transcription factors are targeted to particular DNA sequences in the 5'-flanking region of the erythropoietin gene through engineering of a zinc finger DNA binding domain. The DNA binding domain is linked to a VP16 transcriptional activation domain. We find that these synthetic transcription factors invariably activate transiently transfected templates in which sequences within the 5' flank of the erythropoietin gene are fused to a luciferase reporter. The efficiency of activation under these circumstances at a defined site is dependent on DNA binding affinity. In contrast, only a subset of these same zinc finger proteins is able to activate the endogenous chromosomal locus. The activity of these proteins is influenced by their capacity to gain access to their recognition elements within the chromatin infrastructure. Zinc finger transcription factors will provide a powerful tool to probe the determinants of chromatin accessibility and remodeling within endogenous chromosomal loci.

The cytoplasmic raf oncogene induces a neuronal phenotype in PC12 cells: a potential role for cellular raf kinases in neuronal growth factor signal transduction

The neuron-like differentiation of PC12 cells is induced by nerve growth factor (NGF) through stimulation of a membrane-bound protooncoprotein signaling pathway containing the NGF receptor Trk, the tyrosine kinase Src, and the GTP-binding protein Ras. The Raf-1 and B-raf protooncogenes encode cytoplasmic serine/threonine kinases that are stimulated by NGF in a Ras-dependent manner. To investigate the possible roles of cytoplasmic Raf kinases in eliciting neuronal differentiation, we have expressed the activated Raf-1 oncogene in PC12 cells. Expression of the raf oncogene results in the elaboration of a neuron-like phenotype, including neurite growth and the induction of the NGF-responsive genes NGFI-A and transin. The actions of activated Raf-1 and NGF are not additive. Furthermore, activated Raf-1 oncoprotein can prime cells for transcription-independent neurite growth by NGF and can elicit rapid neurite growth from NGF-primed cells. Our data indicate that the pathways utilized by NGF and activated raf to effect PC12 differentiation overlap and lead to the suggestion that cellular raf kinase activities play significant roles in transducing the differentiating signals of neuronal growth factors.

The protozoan parasite Toxoplasma gondii targets proteins to dense granules and the vacuolar space using both conserved and unusual mechanisms

All known proteins that accumulate in the vacuolar space surrounding the obligate intracellular protozoan parasite Toxoplasma gondii are derived from parasite dense granules. To determine if constitutive secretory vesicles could also mediate delivery to the vacuolar space, T. gondii was stably transfected with soluble Escherichia coli alkaline phosphatase and E. coli beta-lactamase. Surprisingly, both foreign secretory reporters were delivered quantitatively into parasite dense granules and efficiently secreted into the vacuolar space. Addition of a glycosylphosphatidylinositol membrane anchor rerouted alkaline phosphatase to the parasite surface. Alkaline phosphatase fused to the transmembrane domain and cytoplasmic tail from the endogenous dense granule protein GRA4 localized to dense granules. The protein was secreted into a tuboreticular network in the vacuolar space, in a fashion dependent upon the cytoplasmic tail, but not upon a tyrosine-based motif within the tail. Alkaline phosphatase fused to the vesicular stomatitis virus G protein transmembrane domain and cytoplasmic tail localized primarily to the Golgi, although staining of dense granules and the intravacuolar network was also detected; truncating the cytoplasmic tail decreased Golgi staining and increased delivery to dense granules but blocked delivery to the intravacuolar network. Targeting of secreted proteins to T. gondii dense granules and the plasma membrane uses general mechanisms identified in higher eukaryotic cells but is simplified and exaggerated in scope, while targeting of secreted proteins beyond the boundaries of the parasite involves unusual sorting events.

Prenatal anxiety and obstetric decisions among pregnant women in Wuhan and Chongqing during the COVID-19 outbreak: a cross-sectional study

OBJECTIVES

To investigate the mental status of pregnant women and to determine their obstetric decisions during the COVID-19 outbreak.

DESIGN

Cross-sectional study.

SETTING

Two cities in China--Wuhan (epicentre) and Chongqing (a less affected city).

POPULATION

A total of 1947 pregnant women.

METHODS

We collected demographic, pregnancy and epidemic information from our pregnant subjects, along with their attitudes towards COVID-19 (using a self-constructed five-point scale). The Self-Rating Anxiety Scale (SAS) was used to assess anxiety status. Obstetric decision-making was also evaluated. The differences between cities in all of the above factors were compared and the factors that influenced anxiety levels were identified by multivariable analysis.

MAIN OUTCOME MEASURES

Anxiety status and its influencing factors. Obstetric decision-making.

RESULTS

Differences were observed between cities in some background characteristics and women's attitudes towards COVID-19 in Wuhan were more extreme. More women in Wuhan felt anxious (24.5 versus 10.4%). Factors that influenced anxiety also included household income, subjective symptom and attitudes. Overall, obstetric decisions also revealed city-based differences; these decisions mainly concerned hospital preference, time of prenatal care or delivery, mode of delivery and infant feeding.

CONCLUSIONS

The outbreak aggravated prenatal anxiety and the associated factors could be targets for psychological care. In parallel, key obstetric decision-making changed, emphasising the need for pertinent professional advice. Special support is essential for pregnant mothers during epidemics.

TWEETABLE ABSTRACT

The COVID-19 outbreak increased pregnant women's anxiety and affected their decision-making.

Comparative effects of droloxifene, tamoxifen, and estrogen on bone, serum cholesterol, and uterine histology in the ovariectomized rat model

The purpose of this study was to compare the effects of droloxifene (DRO), tamoxifen (TAM), and 17 alpha-ethynyl estradiol (EE) on bone mineral density, bone histomorphometry, total serum cholesterol, and uterine histology in the ovariectomized (ovx) rat model. Sprague-Dawley female rats at five months of age were sham-operated and treated orally with vehicle (n = 8), or ovx (n = 56) and treated (p.o.) with either vehicle, DRO at 0.1 or 1.0 mg/kg daily, TAM at 0.1 or 1 mg/kg daily, or EE at 3 or 30 micrograms/kg daily for 4 weeks. The uterine wet weight and uterine histologic parameters (cross-sectional tissue area, stromal thickness, and luminal epithelial thickness) were determined. Femoral and lumbar vertebral bone mineral density was determined ex vivo using dual energy x-ray absorptiometry. Static and dynamic cancellous bone histomorphometry was performed on double-labeled, undecalcified longitudinal sections from proximal tibial metaphyses. Furthermore, the changes in total serum cholesterol and body weight gain were also determined. Compared to sham controls, ovx for four weeks significantly decreased uterine weight (-72%), uterine cross-sectional tissue area (-74%), stromal thickness (-52%), and luminal epithelial thickness (-53%). ovx rats treated with EE at 30 micrograms/kg/day maintained these parameters at the levels of sham controls. Uterine weight and uterine cross-sectional tissue area in 3 micrograms/kg/day of EE treated ovx rats were higher than that of vehicle-treated ovx rats. In ovx rats treated with TAM at both 0.1 and 1 mg/kg/day, these parameters were significantly less than sham controls but significantly higher than ovx controls. DRO at 0.1 mg/kg/day had no effects on all above parameters. Uterine weight and cross-sectional tissue area in 1 mg/kg/day of DRO treated ovx rats was slightly but significantly higher than that in ovx controls. However, DRO at 1 mg/kg/day had no effects on uterine stromal thickness and luminal epithelial thickness compared to ovx controls. The ovx-induced decrease in femoral and lumbar vertebral bone mineral density was prevented by treatment with EE at 30 micrograms/kg/day, TAM at both 0.1 and 1 mg/kg/day, or DRO at 1 mg/kg/day. Similarly, the decrease in bone mass and the increase in bone resorption and bone turnover in proximal tibial metaphyses were prevented by treatment with EE at 30 micrograms/kg/day or TAM at both 0.1 and 1 mg/kg/day, or DRO at 1 mg/kg/day. Total serum cholesterol decreased significantly in ovx rats treated with either EE, DRO, or TAM at all dose levels compared to vehicle treated ovx controls (-32% to -56%). The ovx-induced body weight gain was completely prevented by EE at 30 micrograms/kg/day, and partially prevented by DRO at 1 mg/kg/day. TAM at both 0.1 and 1 mg doses caused a significant decrease in body weight compared to both sham and ovx controls. Our results indicated that DRO prevented ovx-induced bone loss and lowered total serum cholesterol with an ED50 less than 1 mg/kg/day. The bone protective and cholesterol lowering effects of DRO were comparable to those observed with TAM and EE. However, DRO differed from TAM and EE in its lack of significant estrogenic effects on uterine tissue at doses which were bone protective. These data suggest that DRO may be a significant alternative to EE and TAM for prevention and treatment of postmenopausal osteoporosis.

Cysteine array matrix metalloproteinase (CA-MMP)/MMP-23 is a type II transmembrane matrix metalloproteinase regulated by a single cleavage for both secretion and activation

Matrix metalloproteinases characterized so far are either secreted or membrane anchored via a type I transmembrane domain or a glycosylphosphatidylinositol linkage. Lacking either membrane-anchoring mechanism, the newly discovered CA-MMP/MMP-23 was reported to be expressed as a cell-associated protein. In this report, we present evidence that CA-MMP is expressed as an integral membrane zymogen with an N-terminal signal anchor, and secreted as a fully processed mature enzyme. We further demonstrate that L(20)GAALSGLCLLSALALL(36) is required for this unique membrane localization as a signal anchor and its secretion is regulated by a proprotein convertase motif RRRR(79) sandwiched between its pro- and catalytic domains. Thus, CA-MMP is a type II transmembrane MMP that can be regulated by a single proteolytic cleavage for both activation and secretion, establishing a novel paradigm for protein trafficking and processing within the secretory pathway.

Properties of the Binary Black Hole Merger GW150914

On September 14, 2015, the Laser Interferometer Gravitational-Wave Observatory (LIGO) detected a gravitational-wave transient (GW150914); we characterize the properties of the source and its parameters. The data around the time of the event were analyzed coherently across the LIGO network using a suite of accurate waveform models that describe gravitational waves from a compact binary system in general relativity. GW150914 was produced by a nearly equal mass binary black hole of masses 36_{-4}^{+5}M_{⊙} and 29_{-4}^{+4}M_{⊙}; for each parameter we report the median value and the range of the 90% credible interval. The dimensionless spin magnitude of the more massive black hole is bound to be <0.7 (at 90% probability). The luminosity distance to the source is 410_{-180}^{+160}  Mpc, corresponding to a redshift 0.09_{-0.04}^{+0.03} assuming standard cosmology. The source location is constrained to an annulus section of 610  deg^{2}, primarily in the southern hemisphere. The binary merges into a black hole of mass 62_{-4}^{+4}M_{⊙} and spin 0.67_{-0.07}^{+0.05}. This black hole is significantly more massive than any other inferred from electromagnetic observations in the stellar-mass regime.

Effects of CP-336,156, a new, nonsteroidal estrogen agonist/antagonist, on bone, serum cholesterol, uterus and body composition in rat models

We have discovered a new, nonsteroidal, potent estrogen agonist/antagonist, CP-336,156. CP-336,156 binds selectively and with high affinity to the human estrogen receptor-alpha with a half-inhibition concentration of 1.5 nM, which is similar to that seen with estradiol (4.8 nM). When given orally to immature (3-week-old) female Sprague-Dawley rats for 3 days at doses of 0.1, 1.0, 10, or 100 microg/kg x day, unlike 17alpha-ethynyl estradiol, CP-336,156 had no effect on uterine wet or dry weight. Similarly, no uterine hypertrophy was observed in aged (17-month-old) female rats treated (p.o.) with CP-336,156 at 10 or 100 microg/kg x day for 28 days. We also found that CP-336,156 decreased total serum cholesterol and fat body mass and had no effect on lean body mass in these aged female rats. In 5-month-old ovariectomized (OVX) Sprague-Dawley female rats, CP-336,156 completely prevented OVX-induced increases in body weight gain, total serum cholesterol, and serum osteocalcin at doses between 10 and 1000 microg/kg x day after 4 weeks. At these doses, CP-336,156 completely prevented OVX-induced bone loss and inhibited the increased bone turnover associated with estrogen deficiency in lumbar vertebrae, proximal tibiae, and distal femora. Similar to estrogen, CP-336,156 induced apoptosis and p53 expression with a concomitant decrease in the number of tartrate-resistant acid phosphatase-positive multinuclear cells in rat bone marrow cell cultures in vitro, suggesting that the induction of apoptosis may be a mechanism for the estrogenic activities of CP-336,156 in bone. In summary, CP-336,156 is a new, orally active, nonsteroidal, potent estrogen agonist/antagonist that has similar effects in bone as estradiol but without the uterine-stimulating effects associated with estradiol in rats.

Lactobacillus maintains healthy gut mucosa by producing L-Ornithine

Gut mucosal layers are crucial in maintaining the gut barrier function. Gut microbiota regulate homeostasis of gut mucosal layer via gut immune cells such as RORγt (+) IL-22(+) ILC3 cells, which can influence the proliferation of mucosal cells and the production of mucin. However, it is unclear how gut microbiota execute this regulation. Here we show that lactobacilli promote gut mucosal formation by producing L-Ornithine from arginine. L-Ornithine increases the level of aryl hydrocarbon receptor ligand L-kynurenine produced from tryptophan metabolism in gut epithelial cells, which in turn increases RORγt (+)IL-22(+) ILC3 cells. Human REG3A transgenic mice show an increased proportion of L-Ornithine producing lactobacilli in the gut contents, suggesting that gut epithelial REG3A favors the expansion of L-Ornithine producing lactobacilli. Our study implicates the importance of a crosstalk between arginine metabolism in Lactobacilli and tryptophan metabolism in gut epithelial cells in maintaining gut barrier.