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.

Deep-brain stimulation of the subthalamic nucleus or the pars interna of the globus pallidus in Parkinson's disease

BACKGROUND

Increased neuronal activity in the subthalamic nucleus and the pars interna of the globus pallidus is thought to account for motor dysfunction in patients with Parkinson's disease. Although creating lesions in these structures improves motor function in monkeys with induced parkinsonism and patients with Parkinson's disease, such lesions are associated with neurologic deficits, particularly when they are created bilaterally. Deep-brain stimulation simulates the effects of a lesion without destroying brain tissue.

METHODS

We performed a prospective, double-blind, crossover study in patients with advanced Parkinson's disease, in whom electrodes were implanted in the subthalamic nucleus or pars interna of the globus pallidus and who then underwent bilateral high-frequency deep-brain stimulation. We compared scores on the motor portion of the Unified Parkinson's Disease Rating Scale when the stimulation was randomly assigned to be turned on or off. We performed unblinded evaluations of motor function preoperatively and one, three, and six months postoperatively.

RESULTS

Electrodes were implanted bilaterally in 96 patients in the subthalamic-nucleus group and 38 patients in the globus-pallidus group. Three months after the procedures were performed, double-blind, crossover evaluations demonstrated that stimulation of the subthalamic nucleus was associated with a median improvement in the motor score (as compared with no stimulation) of 49 percent, and stimulation of the pars interna of the globus pallidus with a median improvement of 37 percent (P<0.001 for both comparisons). Between the preoperative and six-month visits, the percentage of time during the day that patients had good mobility without involuntary movements increased from 27 percent to 74 percent (P<0.001) with subthalamic stimulation and from 28 percent to 64 percent (P<0.001) with pallidal stimulation. Adverse events included intracranial hemorrhage in seven patients and infection necessitating removal of the leads in two.

CONCLUSIONS

Bilateral stimulation of the subthalamic nucleus or pars interna of the globus pallidus is associated with significant improvement in motor function in patients with Parkinson's disease whose condition cannot be further improved with medical therapy.

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.

A prospective study of emotional disorders in childbearing women

A group of first-time mothers (119) were interviewed repeatedly at fixed intervals during their pregnancies and until their babies were a year old; they were then followed up at four years. A similar investigation was carried out on 38 other primiparae and 39 multiparae, but only postnatally. The incidence of depressive neurosis rose significantly in early pregnancy and in the first three months after delivery (10 per cent and 14 per cent of the main sample respectively). Subjects mainly suffered either from antenatal or postnatal depression, not both. Marital conflict and severe doubts about having the baby were associated with depression at either time. Bereavement and preterm birth were the only life events to relate with the onset of depression and bereavement had a greater impact during pregnancy. Depressed mothers were more likely to express negative or mixed feelings about their three-month-old babies. Many who had become depressed for the first time in their lives continued to experience psychological problems for up to four years after childbirth.

Hydrogen bonding definitions and dynamics in liquid water

X-ray and neutron diffractions, vibrational spectroscopy, and x-ray Raman scattering and absorption experiments on water are often interpreted in terms of hydrogen bonding. To this end a number of geometric definitions of hydrogen bonding in water have been developed. While all definitions of hydrogen bonding are to some extent arbitrary, those involving one distance and one angle for a given water dimer are unnecessarily so. In this paper the authors develop a systematic procedure based on two-dimensional potentials of mean force for defining cutoffs for a given pair of distance and angular coordinates. They also develop an electronic structure-based definition of hydrogen bonding in liquid water, related to the electronic occupancy of the antibonding OH orbitals. This definition turns out to be reasonably compatible with one of the distance-angle geometric definitions. These two definitions lead to an estimate of the number of hydrogen bonds per molecule in liquid simple point charge/extended (SPC/E) water of between 3.2 and 3.4. They also used these and other hydrogen-bond definitions to examine the dynamics of local hydrogen-bond number fluctuations, finding an approximate long-time decay constant for SPC/E water of between 0.8 and 0.9 ps, which corresponds to the time scale for local structural relaxation.

Dendritic cell modulation by 1alpha,25 dihydroxyvitamin D3 and its analogs: a vitamin D receptor-dependent pathway that promotes a persistent state of immaturity in vitro and in vivo

Dendritic cells (DCs) play a central role in regulating immune activation and responses to self. DC maturation is central to the outcome of antigen presentation to T cells. Maturation of DCs is inhibited by physiological levels of 1alpha,25 dihydroxyvitamin D(3) [1alpha,25(OH)(2)D(3)] and a related analog, 1alpha,25(OH)(2)-16-ene-23-yne-26,27-hexafluoro-19-nor-vitamin D(3) (D(3) analog). Conditioning of bone marrow cultures with 10(-10) M D(3) analog resulted in accumulation of immature DCs with reduced IL-12 secretion and without induction of transforming growth factor beta1. These DCs retained an immature phenotype after withdrawal of D(3) analog and exhibited blunted responses to maturing stimuli (CD40 ligation, macrophage products, or lipopolysaccharide). Resistance to maturation depended on the presence of the 1alpha,25(OH)(2)D(3) receptor (VDR). In an in vivo model of DC-mediated antigen-specific sensitization, D(3) analog-conditioned DCs failed to sensitize and, instead, promoted prolonged survival of subsequent skin grafts expressing the same antigen. To investigate the physiologic significance of 1alpha,25(OH)(2)D(3)/VDR-mediated modulation of DC maturity we analyzed DC populations from mice lacking VDR. Compared with wild-type animals, VDR-deficient mice had hypertrophy of subcutaneous lymph nodes and an increase in mature DCs in lymph nodes but not spleen. We conclude that 1alpha,25(OH)(2)D(3)/VDR mediates physiologically relevant inhibition of DC maturity that is resistant to maturational stimuli and modulates antigen-specific immune responses in vivo.

Neuropsychological consequences of chronic bilateral stimulation of the subthalamic nucleus in Parkinson's disease

The aim of this study was to examine possible neuropsychological changes in patients with advanced idiopathic Parkinson's disease treated with bilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN). Eleven patients (age = 67 +/- 8 years, years with Parkinson's disease = 15 +/- 3, verbal IQ = 114 +/- 12) were evaluated (in their best 'on state') with tests assessing processes reliant on the functional integrity of frontal striatal circuitry, prior to the procedure (n = 11), at 3-6 months (n = 11) and at 9-12 months (n =10) post-operatively. Six of these patients were older than 69 years. Despite clinical motor benefits at 3-6 months post-operative, significant declines were noted in working memory, speed of mental processing, bimanual motor speed and co-ordination, set switching, phonemic fluency, long-term consolidation of verbal material and the encoding of visuospatial material. Declines were more consistently observed in patients who were older than 69 years, leading to a mental state comparable with progressive supranuclear palsy. 'Frontal' behavioural dyscontrol without the benefit of insight was also reported by half (three of six) of the caregivers of the elderly subgroup. At 9-12 months postoperative, only learning based on multiple trials had recovered. Tasks reliant on the integrity of frontal striatal circuitry either did not recover or gradually worsened over time. Bilateral STN DBS can have a negative impact on various aspects of frontal executive functioning, especially in patients older than 69 years. Future studies will evaluate a larger group of patients and examine the possible reversibility of these effects by turning the DBS off.

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.

Double-blind evaluation of subthalamic nucleus deep brain stimulation in advanced Parkinson's disease

OBJECTIVE

To examine objectively the clinical effects of subthalamic nucleus (STN) deep brain stimulation (DBS) in advanced PD.

METHODS

Our initial seven consecutive patients with medication-refractory motor fluctuations and levodopa-induced dyskinesias undergoing chronic STN DBS underwent a standardized preoperative evaluation followed by a 2-day double-blind evaluation of efficacy 6 to 12 months after electrode implantation. Diaries documenting motor fluctuations and dyskinesias were also completed preoperatively and postoperatively.

RESULTS

In the medication-off state, turning the stimulators on resulted in improvement in mean total Unified Parkinson's Disease Rating Scale (UPDRS) motor score by 58% including the following improvements in composite scores: akinesia 57%, rigidity 52%, tremor 82%, and gait and postural stability 49%. Additionally, the medication-off state improved 17% without stimulation, possibly as a result of electrode insertion alone or carry-over of chronic stimulation. In the medication-on, stimulation-on state, all major features of parkinsonism improved and total UPDRS motor score improved 41% compared with before surgery. Activities of daily living were improved while off medication 30%, and levodopa-induced dyskinesias were reduced 83% while total drug dosage was decreased 40%. With chronic stimulation, patients reported that the percentage of time spent in the "on" state (without dyskinesias) increased from 26% to 52% and "off" time decreased from 30% to 6%. Operative complications including cognitive worsening were not uncommon.

CONCLUSIONS

STN DBS is a promising new surgical option for the treatment of advanced PD. The marked clinical benefits obtained in these severely disabled patients outweighed the adverse effects.

Impact of maternal postnatal depression on cognitive development of young children

Ninety four women and their first born children took part in a longitudinal study of maternal mental health during pregnancy and after delivery. The children's cognitive functioning was assessed at age 4 using the McCarthy scales, without knowledge of the mothers' psychiatric history or current health. As expected girls performed slightly better than boys and children from middle class and professional families did better than children from working class homes, as did children whose mothers had achieved at least one A level at school. Significant intellectual deficits were found in the children whose mothers had suffered with depression, but only when this depression occurred in the first year of the child's life. Marital conflict and a history of paternal psychiatric problems were independently linked with lower cognitive test scores; together with a working class home background these were the only factors that contributed to the deleterious effect of maternal postnatal depression.

The effects of nicotine on locomotor activity in non-tolerant and tolerant rats

1--Rats were tested for locomotor activity in photocell cages, for 80 min starting immediately after subcutaneous injection of (-)-nicotine bitartrate or 0.9% w/v NaCl solution (saline). In non-tolerant subjects, nicotine (0.1 to 0.4 mg/kg base) depressed activity and induced ataxia in the first 20 min, but increased activity later in the session; these actions were dose-dependent. 2--Tolerance was studied by comparing rats given nicotine (0.4 mg/kg s.c.) every day with control rats given saline instead. Each week, every subject was tested once with nicotine (0.4 mg/kg) and once with saline. With daily or even weekly injections of nicotine, the initial depressant action of the drug was replaced by a dose-dependent stimulant action which occurred throughout the session. In these tolerant animals, little ataxia was seen except when a larger dose of 0.8 mg/kg was given. Tolerance to the depressant action of nicotine persisted for at least 3 weeks. 3--In non-tolerant subjects, mecamylamine (0.5, 1.0 mg/kg s.c.) prevented the initial depressant action of nicotine (0.4 mg/kg). In tolerant rats, the locomotor stimulant action of nicotine (0.4 mg/kg) was prevented by mecamylamine (0.1, 0.32, 1.0 mg/kg s.c.) in a dose-related way; the quaternary ganglion blocker, hexamethonium (0.2, 1.0, 5.0 mg/kg s.c.) had little or no such effect. Neither mecamylamine nor hexamethonium altered activity when given alone. 4--It is suggested that a few treatments with nicotine can unmask a stimulant action of the drug, probably of central origin, which possibly reflects a stimulation of nicotine receptors.

Characterization of rotavirus strains from newborns in New Delhi, India

Between 1986 and 1993, 72% of rotavirus strains isolated from newborns at five hospitals in New Delhi, India, had long electropherotypes, subgroup II VP6 antigens, and G and P genotypes (G9P11) identical to those of prototype strain 116E. A novel strain with a G9P6 genotype, representing 13% of the isolates, was identified. These results demonstrate that G9P11 and G9P6 rotavirus strains are common in nurseries in New Delhi.

Association of Rab25 and Rab11a with the apical recycling system of polarized Madin-Darby canine kidney cells

Recent evidence suggests that apical and basolateral endocytic pathways in epithelia converge in an apically located, pericentriolar endosomal compartment termed the apical recycling endosome. In this compartment, apically and basolaterally internalized membrane constituents are thought to be sorted for recycling back to their site of origin or for transcytosis to the opposite plasma membrane domain. We report here that in the epithelial cell line Madin-Darby Canine Kidney (MDCK), antibodies to Rab11a label an apical pericentriolar endosomal compartment that is dependent on intact microtubules for its integrity. Furthermore, this compartment is accessible to a membrane-bound marker (dimeric immunoglobulin A [IgA]) internalized from either the apical or basolateral pole, functionally defining it as the apical recycling endosome. We have also examined the role of a closely related epithelial-specific Rab, Rab25, in the regulation of membrane recycling and transcytosis in MDCK cells. When cDNA encoding Rab25 was transfected into MDCK cells, the protein colocalized with Rab11a in subapical vesicles. Rab25 transfection also altered the distribution of Rab11a, causing the coalescence of immunoreactivity into multiple denser vesicular structures not associated with the centrosome. Nevertheless, nocodazole still dispersed these vesicles, and dimeric IgA internalized from either the apical or basolateral membrane was detected in endosomes labeled with antibodies to both Rab11a and Rab25. Overexpression of Rab25 decreased the rate of IgA transcytosis and of apical, but not basolateral, recycling of internalized ligand. Conversely, expression of the dominant-negative Rab25T26N did not alter either apical recycling or transcytosis. These results indicate that both Rab11a and Rab25 associate with the apical recycling system of epithelial cells and suggest that Rab25 may selectively regulate the apical recycling and/or transcytotic pathways.

Macrophage-derived metalloelastase is responsible for the generation of angiostatin in Lewis lung carcinoma

To determine the mechanism responsible for the in vivo production of angiostatin that inhibits growth and metastasis in Lewis lung carcinoma (3LL), we implanted 3LL variant cells into the subcutis of syngeneic C57BL/6 mice. The tumors were infiltrated by macrophages and expressed high levels of steady-state mRNA for metalloelastase (MME). Successive passages (more than three) of cultures established from the tumors resulted in complete depletion of macrophages; steady-state MME mRNA, elastinolytic activity, and production of angiostatin (in the presence of plasminogen) were correspondingly reduced. Coculture of macrophages with either 3LL cells or their conditioned media containing granulocyte-macrophage colony-stimulating factor resulted in secretion of MME and production of angiostatin by the macrophages, suggesting that angiostatin is produced by tumor-infiltrating macrophages whose MME expression is stimulated by tumor cell-derived granulocyte-macrophage colony-stimulating factor.

Myosin vb is associated with plasma membrane recycling systems

Myosin Va is associated with discrete vesicle populations in a number of cell types, but little is known of the function of myosin Vb. Yeast two-hybrid screening of a rabbit parietal cell cDNA library with dominant active Rab11a (Rab11aS20V) identified myosin Vb as an interacting protein for Rab11a, a marker for plasma membrane recycling systems. The isolated clone, corresponding to the carboxyl terminal 60 kDa of the myosin Vb tail, interacted with all members of the Rab11 family (Rab11a, Rab11b, and Rab25). GFP-myosin Vb and endogenous myosin Vb immunoreactivity codistributed with Rab11a in HeLa and Madin-Darby canine kidney (MDCK) cells. As with Rab11a in MDCK cells, the myosin Vb immunoreactivity was dispersed with nocodazole treatment and relocated to the apical corners of cells with taxol treatment. A green fluorescent protein (GFP)-myosin Vb tail chimera overexpressed in HeLa cells retarded transferrin recycling and caused accumulation of transferrin and the transferrin receptor in pericentrosomal vesicles. Expression of the myosin Vb tail chimera in polarized MDCK cells stably expressing the polymeric IgA receptor caused accumulation of basolaterally endocytosed polymeric IgA and the polymeric IgA receptor in the pericentrosomal region. The myosin Vb tail had no effects on transferrin trafficking in polarized MDCK cells. The GFP-myosin Va tail did not colocalize with Rab11a and had no effects on recycling system vesicle distribution in either HeLa or MDCK cells. The results indicate myosin Vb is associated with the plasma membrane recycling system in nonpolarized cells and the apical recycling system in polarized cells. The dominant negative effects of the myosin Vb tail chimera indicate that this unconventional myosin is required for transit out of plasma membrane recycling systems.

Transdermal oestrogen for treatment of severe postnatal depression

BACKGROUND

Postnatal depression can have long-term adverse consequences for the mother, for the marital relationship, and for the infant's psychological development. Such depressions can be severe and resistant to both support and counselling and to therapy with antidepressant drugs. We investigated the antidepressant efficacy of oestrogen given transdermally.

METHODS

In a double-blind, placebo-controlled study, 61 women with major depression, which began within 3 months of childbirth and persisted for up to 18 months postnatally, were allocated randomly active treatment (n=34; 3 months of transdermal 17 beta-oestradiol 200 micrograms daily alone, then 3 months with added cyclical dydrogesterone 10mg daily for 12 days each month) or placebo (n=27; placebo patches and tablets according to the same regimen). The women were assessed monthly by self-ratings of depressive symptoms on the Edinburgh postnatal depression scale (EPDS) and by clinical psychiatric interview (schedule for affective disorders and schizophrenia [SADS]-change scale).

FINDINGS

On pretreatment assessments the women in both groups were severely depressed (mean EPDS score 21.8 [SD 3.0] active group, 21.3 [2.9] placebo group; SADS scores, 66.3 [11.4] and 64.3 [10.7]). During the first month of therapy the women receiving oestrogen improved rapidly, and to a significantly greater extent than controls (mean EPDS scores 13.3 [SD 5.7] vs 16.5 [5.3]. Patients receiving placebo also improved over time but, on average, their scores did not fall below the screening threshold for major depression for at least 4 months. The estimated overall treatment effect of oestrogen on the EPDS was 4.38 points (95% Cl 1.89-6.87). None of a range of other factors (age, psychiatric, obstetric and gynaecological history, severity and duration of current episode of depression, and concurrent antidepressant medication), influenced the response to oestrogen.

INTERPRETATION

This study has shown that transdermal oestrogen is an effective treatment for postnatal depression. Further studies are required to establish the minimum effective dose and shortest necessary duration of treatment as well as the mechanism of antidepressant action of oestrogen.

Randomized, double-blind, placebo-controlled trial of fish oil and mustard oil in patients with suspected acute myocardial infarction: the Indian experiment of infarct survival--4

In a randomized, placebo-controlled trial, the effects of treatment with fish oil (eicosapentaenoic acid, 1.08 g/day) and mustard oil (alpha-linolenic acid, 2.9 g/day) were compared for 1 year in the management of 122 patients (fish oil, group A), 120 patients (mustard oil, group B), and 118 patients (placebo, group C) with suspected acute myocardial infarction (AMI). Treatments were administered about (mean) 18 hours after the symptoms of AMI in all three groups. The extent of cardiac disease, rise in cardiac enzymes, and lipid peroxides were comparable among the groups at entry into the study. After 1 year total cardiac events were significantly less in the fish oil and mustard oil groups compared with the placebo group (24.5% and 28% vs. 34.7%, p < 0.01). Nonfatal infarctions were also significantly less in the fish oil and mustard oil groups compared with the placebo group (13.0% and 15.0% vs. 25.4%, p < 0.05). Total cardiac deaths showed no significant reduction in the mustard oil group; however, the fish oil group had significantly less cardiac deaths compared with the placebo group (11.4% vs. 22.0%, p < 0.05). Apart from the decrease in the cardiac event rate, the fish oil and mustard oil groups also showed a significant reduction in total cardiac arrhythmias, left ventricular enlargement, and angina pectoris compared with the placebo group. Reductions in blood lipoproteins in the two intervention groups were modest and do not appear to be the cause of the benefit in the two groups. Diene conjugates showed a significant reduction in the fish oil and mustard oil groups, indicating that a part of the benefit may be caused by the reduction in oxidative stress. The findings of this study suggest that fish oil and mustard oil, possibly due to the presence of n-3 fatty acids, may provide rapid protective effects in patients with AMI. However, a large study is necessary to confirm this suggestion.

Intellectual problems shown by 11-year-old children whose mothers had postnatal depression

The aim of the study was to examine long-term sequelae in the children of mothers who were depressed at 3 months postpartum. In a community sample from two general practices in South London. 149 women were given psychiatric interviews at 3 months postpartum and 132 of their children (89 %) were tested at 11 years of age. The children of women who were depressed at 3 months postpartum had significantly lower IQ scores. They also had attentional problems and difficulties in mathematical reasoning. and were more likely than other children to have special educational needs. Boys were more severely affected than girls, with the sex difference most pronounced on Performance IQ. The links between postnatal depression and the children's intellectual problems were not mediated by parental IQ and were not accounted for by measures of social disadvantage nor by the mother's later mental health problems. Breastfeeding did not remove the effect of the mother's illness on Full Scale IQ, but exerted its own influence on Verbal IQ and appeared to mediate the link with mathematical ability. The findings show that adverse experiences in infancy predict cognitive ability and academic performance a decade later.

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.

Review of G and P typing results from a global collection of rotavirus strains: implications for vaccine development

Candidate rotavirus vaccines have been prepared with reassortant strains specifically to protect against the 4 major rotavirus G serotypes (G1 -4). Many studies using P (VP4) genotyping methods have indicated that, worldwide, rotavirus strains of the 4 common G serotypes are each associated with 1 P genotype: GI, G3, and G4 are associated with P[8], and G2 is associated with P[4]. In contrast, G and P genotyping of rotavirus in specimens from India revealed that a high percentage of the childhood diarrhea strains belong to genotype P[6], and the most common strain had an unusual G serotype, G9. Similarly, in all regions surveyed in Brazil, apparent reassortants of genotype P[8], G5 were found in children with gastroenteritis. These studies indicate that while rotavirus strains have limited diversity in many settings, reassortment between common and uncommon serotypes or animal strains can arise in some settings and, thus, lead to unusual diversity.

Inhibition of platelet-mediated, tissue factor-induced thrombin generation by the mouse/human chimeric 7E3 antibody. Potential implications for the effect of c7E3 Fab treatment on acute thrombosis and "clinical restenosis"

The murine/human chimeric monoclonal antibody fragment (c7E3 Fab) blocks GPIIb/IIIa and alpha v beta 3 receptors, inhibits platelet aggregation, and decreases the frequency of ischemic events after coronary artery angioplasty in patients at high risk of suffering such events. Although inhibition of platelet aggregation is likely to be the major mechanism of c7E3 Fab's effects, since activated platelets facilitate thrombin generation, it is possible that c7E3 Fab also decreases thrombin generation. To test this hypothesis, the effects of c7E3 Fab and other antiplatelet agents were tested in a thrombin generation assay triggered by tissue factor. c7E3 Fab produced dose-dependent inhibition of thrombin generation, reaching a plateau of 45-50% inhibition at concentrations > or = 15 micrograms/ml. It also inhibited thrombin-antithrombin complex formation, prothrombin fragment F1-2 generation, platelet-derived growth factor and platelet factor 4 release, incorporation of thrombin into clots, and microparticle formation. Antibody 6D1, which blocks platelet GPIb binding of von Willebrand factor, had no effect on thrombin generation, whereas antibody 10E5, which blocks GPIIb/IIIa but not alpha v beta 3 receptors decreased thrombin generation by approximately 25%. Combining antibody LM609, which blocks alpha v beta 3 receptors, with 10E5 increased the inhibition of thrombin generation to approximately 32-41%. The platelets from three patients with Glanzmann thrombasthenia, who lacked GPIIb/IIIa receptors but had normal or increased alpha v beta 3 receptors, supported approximately 21% less thrombin generation than normal platelets. We conclude that thrombin generation initiated by tissue factor in the presence of platelets is significantly inhibited by c7E3 Fab, most likely in part through both GPIIb/IIIa and alpha v beta 3 blockade, and that this effect may contribute to its antithrombotic properties.

The structure of the nuclear hormone receptors

The functions of the group of proteins known as nuclear receptors will be understood fully only when their working three-dimensional structures are known. These ligand-activated transcription factors belong to the steroid-thyroid-retinoid receptor superfamily, which include the receptors for steroids, thyroid hormone, vitamins A- and D-derived hormones, and certain fatty acids. The majority of family members are homologous proteins for which no ligand has been identified (the orphan receptors). Molecular cloning and structure/function analyses have revealed that the members of the superfamily have a common functional domain structure. This includes a variable N-terminal domain, often important for transactivation of transcription; a well conserved DNA-binding domain, crucial for recognition of specific DNA sequences and protein:protein interactions; and at the C-terminal end, a ligand-binding domain, important for hormone binding, protein: protein interactions, and additional transactivation activity. Although the structure of some independently expressed single domains of a few of these receptors have been solved, no holoreceptor structure or structure of any two domains together is yet available. Thus, the three-dimensional structure of the DNA-binding domains of the glucocorticoid, estrogen, retinoic acid-beta, and retinoid X receptors, and of the ligand-binding domains of the thyroid, retinoic acid-gamma, retinoid X, estrogen, progesterone, and peroxisome proliferator activated-gamma receptors have been solved. The secondary structure of the glucocorticoid receptor N-terminal domain, in particular the taul transcription activation region, has also been studied. The structural studies available not only provide a beginning stereochemical knowledge of these receptors, but also a basis for understanding some of the topological details of the interaction of the receptor complexes with coactivators, corepressors, and other components of the transcriptional machinery. In this review, we summarize and discuss the current information on structures of the steroid-thyroid-retinoid receptors.

Transcriptional repression of oestrogen receptor by metastasis-associated protein 1 corepressor

Activation of the heregulin/HER2 pathway in oestrogen receptor (ER)-positive breast-cancer cells leads to suppression of oestrogen-receptor element (ERE)-driven transcription and disruption of oestradiol responsiveness, and thus contributes to progression of tumours to more invasive phenotypes. Here we report the identification of metastatic-associated protein 1 (MTA1), a component of histone deacetylase (HDAC) and nucleosome-remodelling complexes, as a gene product induced by heregulin-beta1 (HRG). Stimulation of cells with HRG is accompanied by suppression of histone acetylation and enhancement of deacetylase activity. MTA1 is also a potent corepressor of ERE transcription, as it blocks the ability of oestradiol to stimulate ER-mediated transcription. The histone-deacetylase inhibitor trichostatin A blocks MTA1-mediated repression of ERE transcription. Furthermore, MTA1 directly interacts with histone deacetylase-1 and -2 and with the activation domain of ER-alpha. Overexpression of MTA1 in breast-cancer cells is accompanied by enhancement of the ability of cells to invade and to grow in an anchorage-independent manner. HRG also promotes interaction of MTA1 with endogenous ER and association of MTA1 or HDAC with ERE-responsive target-gene promoters in vivo. These results identify ER-mediated transcription as a nuclear target of MTA1 and indicate that HDAC complexes associated with the MTA1 corepressor may mediate ER transcriptional repression by HRG.

Typhoid fever in children aged less than 5 years

BACKGROUND

Calculation of the incidence of typhoid fever during preschool years is important to define the optimum age of immunisation and the choice of vaccines for public-health programmes in developing countries. Hospital-based studies have suggested that children younger than 5 years do not need vaccination against typhoid fever, but this view needs to be re-examined in community-based longitudinal studies. We undertook a prospective follow-up study of residents of a low-income urban area of Delhi, India, with active surveillance for case detection.

METHODS

A baseline census was undertaken in 1995. Between Nov 1, 1995, and Oct 31, 1996, we visited 8172 residents of 1820 households in Kalkaji, Delhi, twice weekly to detect febrile cases. Blood samples were obtained from febrile patients, and those who tested positive for Salmonella typhi were treated with ciprofloxacin.

FINDINGS

63 culture-positive typhoid fever cases were detected. Of these, 28 (44%) were in children aged under 5 years. The incidence rate of typhoid per 1000 person-years was 27.3 at age under 5 years, 11.7 at 5-19 years, and 1.1 between 19 and 40 years. The difference in the incidence of typhoid fever between those under 5 years and those aged 5-19 years (15.6 per 1000 person-years [95% CI 4.7-26.5]), and those aged 19-40 years (26.2 [16.0-36.3]) was significant (p<0.001 for both). The difference between the incidence of typhoid at 5-19 years and the incidence at 19-40 years was also significant (10.6 [6.3-14.8], p<0.001). Morbidity in those under 5 and in older people was similar in terms of duration of fever, signs and symptoms, and need for hospital admission.

INTERPRETATION

Our findings challenge the common view that typhoid fever is a disorder of school-age children and of adults. Typhoid is a common and significant cause of morbidity between 1 and 5 years of age. The optimum age of typhoid immunisation and the choice of vaccines needs to be reassessed.

FGF-23 inhibits renal tubular phosphate transport and is a PHEX substrate

Oncogenic osteomalacia (OOM), X-linked hypophosphatemia (XLH), and autosomal dominant hypophosphatemic rickets (ADHR) are phenotypically similar disorders characterized by hypophosphatemia, decreased renal phosphate reabsorption, normal or low serum calcitriol concentrations, normal serum concentrations of calcium and parathyroid hormone, and defective skeletal mineralization. XLH results from mutations in the PHEX gene, encoding a membrane-bound endopeptidase, whereas ADHR is associated with mutations of the gene encoding FGF-23. Recent evidence that FGF-23 is expressed in mesenchymal tumors associated with OOM suggests that FGF-23 is responsible for the phosphaturic activity previously termed "phosphatonin." Here we show that both wild-type FGF-23 and the ADHR mutant, FGF-23(R179Q), inhibit phosphate uptake in renal epithelial cells. We further show that the endopeptidase, PHEX, degrades native FGF-23 but not the mutant form. Our results suggest that FGF-23 is involved in the pathogenesis of these three hypophosphatemic disorders and directly link PHEX and FGF-23 within the same biochemical pathway.