Swift and NuSTAR observations of GW170817: Detection of a blue kilonova

With the first direct detection of merging black holes in 2015, the era of gravitational wave (GW) astrophysics began. A complete picture of compact object mergers, however, requires the detection of an electromagnetic (EM) counterpart. We report ultraviolet (UV) and x-ray observations by Swift and the Nuclear Spectroscopic Telescope Array of the EM counterpart of the binary neutron star merger GW170817. The bright, rapidly fading UV emission indicates a high mass (≈0.03 solar masses) wind-driven outflow with moderate electron fraction (Y_e ≈ 0.27). Combined with the x-ray limits, we favor an observer viewing angle of ≈30° away from the orbital rotation axis, which avoids both obscuration from the heaviest elements in the orbital plane and a direct view of any ultrarelativistic, highly collimated ejecta (a γ-ray burst afterglow).

Conformational Switching of a Foldamer in a Multicomponent System by pH-Filtered Selection between Competing Noncovalent Interactions

Biomolecular systems are able to respond to their chemical environment through reversible, selective, noncovalent intermolecular interactions. Typically, these interactions induce conformational changes that initiate a signaling cascade, allowing the regulation of biochemical pathways. In this work, we describe an artificial molecular system that mimics this ability to translate selective noncovalent interactions into reversible conformational changes. An achiral but helical foldamer carrying a basic binding site interacts selectively with the most acidic member of a suite of chiral ligands. As a consequence of this noncovalent interaction, a global absolute screw sense preference, detectable by (13)C NMR, is induced in the foldamer. Addition of base, or acid, to the mixture of ligands competitively modulates their interaction with the binding site, and reversibly switches the foldamer chain between its left and right-handed conformations. As a result, the foldamer-ligand mixture behaves as a biomimetic chemical system with emergent properties, functioning as a "proton-counting" molecular device capable of providing a tunable, pH-dependent conformational response to its environment.

Three-minute step test to assess exercise capacity in children with cystic fibrosis with mild lung disease

The information obtained from a simple submaximal test (the 3-min step test) was compared with that from a maximal cycle ergometry study, in a group of children with CF with relatively mild abnormalities of lung function (FEV(1) > 50% predicted). Nineteen subjects with CF undertook both exercise tests on the same day. Measurements included heart rate (HR), oxygen saturations (SaO(2)), visual analogue score of perceived breathlessness (VAS), 15-count breathlessness score (15c), and peak oxygen consumption (VO(2)). There were significant differences in the median changes in HR and VAS during the cycle test compared to the step test, 78 vs. 46 beats per minute (P < 0.05) and 51 mm vs. 42 mm (P < 0.05), respectively. There were no differences between median changes in 15c and SaO(2), but 3 subjects had significant desaturations (>4%) during the cycle test only. Significant exercise desaturations may occur in mild CF lung disease and will not be detected by a 3-min step test. The 15c did not discriminate between a maximal and a submaximal test, and was less useful than VAS. Important information may be missed by the step test which is detected by more complex exercise tests.

Biological activity of harpin produced by Pantoea stewartii subsp. stewartii

Pantoea stewartii subsp. stewartii causes Stewart's wilt of sweet corn. A hypersensitive response and pathogenicity (Hrp) secretion system is needed to produce water-soaking and wilting symptoms in corn and to cause a hypersensitive response (HR) in tobacco. Sequencing of the hrp cluster revealed a putative harpin gene, hrpN. The product of this gene was overexpressed in Escherichia coli and shown to elicit the HR in tobacco and systemic resistance in radishes. The protein was designated HrpN(Pnss). Like other harpins, it was heat stable and protease sensitive, although it was three- to fourfold less active biologically than Erwinia amylovora harpin. We used antibodies to purified HrpN(Pnss) to verify that hrpN mutants could not produce harpin. This protein was secreted into the culture supernatant and was produced by strains of P. stewartii subsp. indologenes. In order to determine the importance of HrpN(Pnss) in pathogenesis on sweet corn, three hrpN::Tn5 mutants were compared with the wild-type strain with 50% effective dose, disease severity, response time, and growth rate in planta as parameters. In all tests, HrpN(Pnss) was not required for infection, growth, or virulence in corn or endophytic growth in related grasses.

Advances in the in vivo measurement of normal and abnormal carpal kinematics

This article presents the development of an in vivo, three-dimensional methodology using markerless bone registration for examining the normal and abnormal kinematics of the wrist carpal bones. The resulting descriptions of three-dimensional kinematics from healthy patients and patients with documented unilateral scapholunate interosseous ligament injuries are briefly presented.

Size-fractionated plutonium isotopes in a coastal environment

We have examined the distribution of individual Pu isotopes (239Pu, 240Pu, and 241Pu) in seawater from the Gulf of Maine (GOM). Samples were size-fractionated with a 1 kD cross-flow ultrafiltration (CFF) membrane. Subfractioned samples were radiochemically purified and Pu isotopes were analyzed using a three-stage thermal ionization mass spectrometer (TIMS). To our knowledge, this is the first time that both size class and Pu isotopic data have been obtained for seawater samples. Within measurement uncertainties a single 240Pu/239Pu atom ratio of 0.18 was found for all sample collection depths and sample size fractions. This signifies a current, single Pu source in GOM waters, namely global fallout, and suggests that no measurable isotopic fractionation occurred during CFF processing. The majority of Pu was found in the low molecular weight fraction (< 1 kD). Colloidal Pu varied from 8% of the total in surface waters to < 1% in the deepest (250 m) seawater sample. Evidence suggests that the vertical distribution of Pu in GOM is primarily controlled by conservative mixing processes. The high Pu fraction found in the low molecular size fraction implies that most of the Pu is in the non-particle-reactive oxidized fraction, and is consistent with the conservative Pu behavior. The activity levels are in agreement with other studies which show a slow decrease in Pu with time due to continued mixing and relatively slow particle removal.

Clinical predictors of acute response with olanzapine in psychotic mood disorders

BACKGROUND

In controlled studies of patients with schizophrenia, the atypical antipsychotic olanzapine has been shown to be more effective in the treatment of positive and negative symptoms compared with haloperidol at doses of 10 mg/day. However, little is known about the efficacy of olanzapine in patients with psychotic mood disorders. The purpose of this study was to assess the efficacy of olanzapine in the treatment of these psychotic mood disorders in comparison with nonaffective psychotic disorders and to identify clinical factors associated with olanzapine response.

METHOD

In a naturalistic setting, by reviewing medical records, we assessed response to olanzapine and factors associated with response to olanzapine in 150 consecutive patients newly treated with the drug at a nonprofit academic psychiatric hospital.

RESULTS

Patients displaying a moderate-to-marked response to olanzapine were more likely to be younger; be female; receive a diagnosis of bipolar disorder; and have a shorter duration of illness, shorter length of stay prior to olanzapine, and longer duration of trial.

CONCLUSION

Olanzapine may be a useful alternative or adjunctive treatment for patients with bipolar disorder.

Rapid and Transient Activation of a Myelin Basic Protein Kinase in Tobacco Leaves Treated with Harpin from Erwinia amylovora

Harpins are bacterial protein elicitors that induce hypersensitive response-like necrosis when infiltrated into nonhost plants such as tobacco (Nicotiana tabacum L.) (Z.-M. Wei, R.J. Laby, C.H. Zumoff, D.W. Bauer, S.Y. He, A. Collmer, S.V. Beer [1992] Science 257: 85-88). Activity of a 49-kD Mg2+-dependent and Ca2+-independent kinase in tobacco leaves increased 50-fold 15 min after infiltration of harpin from Erwinia amylovora (harpinEa). Much less pronounced and more transient activation was detected in water-infiltrated leaves. Biochemical characteristics of the harpinEa-activated protein kinase (HAPK) activity are consistent with those of the mitogen-activated protein kinase family. HAPK is cytosolic and phosphorylates myelin basic protein on serine/threonine residues. Treatment with a protein tyrosine phosphatase completely eliminated HAPK activity, suggesting that tyrosine phosphorylation is required for posttranslational activation. Sustained HAPK activation after cycloheximide treatment implies that HAPK may be negatively regulated by a translation-dependent mechanism. The extracellular Ca2+ chelator EGTA or the protein kinase inhibitor K252a, infiltrated in planta together with harpinEa, partially blocked HAPK activation. The Ca2+-channel blocker La3+ had no effect on HAPK activation, suggesting that phosphorylation events precede and/or do not depend on the entry of extracellular Ca2+ into the cell. These results suggest that early signal transduction events during harpinEa- induced hypersensitive response elicitation depend in part on the activation of HAPK.

Telephone versus in-person clinical and health status assessment interviews in patients with bipolar disorder

We evaluated the correspondence between in-person- and telephone interview-derived data on affective symptoms, health-related quality of life, disability days, and medication compliance in patients with bipolar disorder. Twenty-eight outpatients with DSM-III-R-documented bipolar disorder were randomly assigned to an initial in-person or telephone interview. An average of 4.0 days later, they were reassessed by the other interview method. Results indicate good to excellent agreement between telephone and in-person interviews on measures of mania (intraclass correlation coefficient (ICC) = 0.92) and depression symptoms (ICC = 0.90), suicide risk (kappa = 0.80), and alcohol use (kappa = 0.61), scores on the Medical Outcomes Study 36-item Short-Form Health Survey (ICCs = 0.66-0.92), and medication compliance (ICCs = 0.50-0.66). Measures of bed disability days (ICC = 0.34) and restricted activity days (ICC = 0.66) showed less agreement. Telephone interviews are feasible and reliable for collecting data on psychiatric and other health-related outcomes in bipolar disorder patients.

An evaluation of counselling for couples undergoing treatment for in-vitro fertilization

Fertility difficulties, along with their investigation and treatment, are widely believed to cause significant psychological problems. This study was designed to investigate the efficacy of a non-directive counselling intervention with couples undertaking their first cycle of in-vitro fertilization treatment. Couples were randomly assigned to either a control group, given information about the treatment programme, or to an experimental group, given the same information plus three sessions of counselling before, during and on conclusion of the first treatment cycle. Psychological assessments were made at three points in the treatment process. Ratings were also obtained from the couples on the stress engendered by different parts of the treatment, the effects on their relationship and satisfaction with counselling. The results showed the patients to be generally well adjusted and anxiety levels dropped over the course of treatment. Counselling compared to information alone did not lead to any enhanced reduction in levels of anxiety or depression. The implications of the findings for service provision are discussed.

Ethics, the law and clinical decisions

Many nurse educators wonder how they can teach their students to make ethical decisions. The Newfoundland School of Nursing has found a unique way to address this nebulous ability: the Moot Court. The Moot Court (or mock trial) enables students to explore the legal and ethical issues that arise in an imaginary court case.

The polymerase chain reaction: an epidemiological tool to differentiate between two clusters of pathogenic Yersinia enterocolitica strains

A primer set designed to amplify the enterotoxin (yst) gene of pathogenic Yersinia enterocolitica strains generated two different electrophoretic profiles of the target sequence when a collection of strains of worldwide origin was screened. Serovars O:1,3; O:2a,3; O:3; O:5,27 and O:9, known as European strains, produced a 200-bp fragment that matched the size of the target sequence. However, serovars O:4,32; O:8; O:13a,13b; O:20 and O:21, known as American strains, generated two fragments of 1.4 and 1.6 kb. The amplified products of one American strain were sequenced and the presence of the yst gene was confirmed in both fragments. Thus, the potential of the polymerase chain reaction to be used as an epidemiological tool in differentiation between the two clusters of pathogenic strains of Y. enterocolitica could be demonstrated.

A nursing intervention: the design and implementation of a cardiovascular health

The design and implementation of a Cardiovascular Health Education Program (CHEP) tailored to meet the needs of adolescents will be discussed. As well, findings concerning the impact of the program on the cardiovascular health knowledge of junior high school adolescents will be reported. The program consisted of seven educational modules implemented within seven of the health classes in one grade eight class of junior high school adolescents (N = 28). The impact of the program was assessed using the Cardiovascular Health Knowledge Questionnaire (CHKQ) (Williams, Arnold & Wynder, 1977) with an experimental and control group. The CHKQ was administered prior to the implementation of the CHEP (pre-test), immediately after its implementation (post-test 1), and four months later (post-test 2). Both the experimental and control groups scored poorly on the pretest. The experimental group mean score significantly improved on post-test 1 (p less than .05) and this improvement was maintained on post-test 2. The control group however did not demonstrate any significant improvement on any of the post-tests. The findings of this study demonstrate that a cardiovascular health education program tailored specifically for adolescents had an impact on the cardiovascular health knowledge of the adolescents in this study. Further research is warranted to assess the impact of the program on adolescent cardiovascular health attitudes and behaviors.

A programme to support your extended role. Chemotherapy training for paediatric nurses

The holistic care offered to children with cancer could be improved if nurses administered chemotherapy. This article describes how staff at the Hospital for Sick Children set up an education programme to prepare them for this extended role.

Lack of effect of vitamin B-6 supplementation on the lipoprotein profile of post-menopausal chronic hemodialysis patients

This study was designed to analyze the effect of vitamin B-6 supplementation on the lipoprotein profile of chronic hemodialysis patients. Individuals on chronic hemodialysis experience an acceleration of atherosclerosis, which is often accompanied by abnormal lipid metabolism. Although total plasma cholesterol is usually normal, high-density-lipoprotein (HDL) cholesterol is often low. Recently, it has been suggested that the development of atherosclerotic lesions in chronic hemodialysis patients may be the result of a decreased plasma concentration of pyridoxal 5'-phosphate (PLP) and concomitant alterations in plasma amino acid and/or lipoprotein profiles. All subjects in this study were supplemented with 0.97 mmol (200 mg) pyridoxine hydrochloride per day for 28 days; then, concentrations of PLP, total cholesterol, and lipoprotein cholesterol fractions were determined in the plasma. No significant difference was noted in PLP concentration between Group 1 (five post-menopausal women with a history of atherosclerosis who were undergoing maintenance hemodialysis therapy) and Group 2 (six subjects who were non-symptomatic). However, both groups had significant increases in PLP concentrations between the pre- and post-supplementation periods (p less than .01). In contrast, there was a statistically significant difference in total plasma cholesterol and very-low-density- and low-density-lipoprotein (VLDL and LDL) cholesterol concentrations between groups, but no significant changes in total cholesterol or VLDL and LDL cholesterol content were found during vitamin B-6 supplementation. No statistically significant differences in HDL, HDL2, and HDL3 cholesterol concentrations were observed between Group 1 and Group 2 subjects or within either group during vitamin B-6 supplementation.

Glucocorticosteroids stimulate polyclonal immunoglobulin production by cord blood mononuclear cells

Glucocorticosteroids (GCS) are in vitro polyclonal activators of immunoglobulin (Ig) production for human mononuclear cells (MC) from virtually all adult donors. However, GCS treatment of cord blood MC resulted in Ig production in only 12/41 samples. This GCS effect is T cell and monocyte dependent and is mediated in part by a soluble T cell replacing factor. The inconsistent response of cord MC could be due to either cellular or soluble factor differences from adults. In 11/12 samples tested, irradiated cord T cells did help adult B cells, but less than did irradiated allogeneic adult T cells. T cell suppression in cord samples is unlikely inasmuch as higher cord T cell numbers and proportions increased the number of responding cord samples. Cord monocytes function adequately, because monocytes supported GCS responses when cord non-T cells had sufficient T cell help. The T cell replacing factor was found in supernatants of unstimulated cord as well as in adult MC cultures, but was less than 50% as potent. Cord B cells did not develop GCS-induced Ig production with such supernatants, suggesting that cord B cells may require a higher concentration or more prolonged exposure to T cell help. With a 2:1 ratio of irradiated adult T cells to cord non-T cells, only 25% of cord samples responded to GCS (compared to greater than 95% of adult samples), but with a ratio of 4:1, 75% responded. IgM was the predominant isotype secreted by GCS-stimulated cord cells, but 6/14 samples also produced IgG and 8/14 produced IgA. Thus, the functional immaturity of both cord T and B cells exists for GCS-induced Ig production, but with appropriate conditions GCS can activate most samples of cord B cells to synthesize Ig.

Glucocorticosteroids stimulate polyclonal immunoglobulin production by cord blood mononuclear cells

Glucocorticosteroids (GCS) are in vitro polyclonal activators of immunoglobulin (Ig) production for human mononuclear cells (MC) from virtually all adult donors. However, GCS treatment of cord blood MC resulted in Ig production in only 12/41 samples. This GCS effect is T cell and monocyte dependent and is mediated in part by a soluble T cell replacing factor. The inconsistent response of cord MC could be due to either cellular or soluble factor differences from adults. In 11/12 samples tested, irradiated cord T cells did help adult B cells, but less than did irradiated allogeneic adult T cells. T cell suppression in cord samples is unlikely inasmuch as higher cord T cell numbers and proportions increased the number of responding cord samples. Cord monocytes function adequately, because monocytes supported GCS responses when cord non-T cells had sufficient T cell help. The T cell replacing factor was found in supernatants of unstimulated cord as well as in adult MC cultures, but was less than 50% as potent. Cord B cells did not develop GCS-induced Ig production with such supernatants, suggesting that cord B cells may require a higher concentration or more prolonged exposure to T cell help. With a 2:1 ratio of irradiated adult T cells to cord non-T cells, only 25% of cord samples responded to GCS (compared to greater than 95% of adult samples), but with a ratio of 4:1, 75% responded. IgM was the predominant isotype secreted by GCS-stimulated cord cells, but 6/14 samples also produced IgG and 8/14 produced IgA. Thus, the functional immaturity of both cord T and B cells exists for GCS-induced Ig production, but with appropriate conditions GCS can activate most samples of cord B cells to synthesize Ig.

T cell-replacing factor for glucocorticosteroid-induced immunoglobulin production. A unique steroid-dependent cytokine

Glucocorticosteroids (GCS) added to otherwise unstimulated cultures of human peripheral blood mononuclear cells (PBMC) induce the synthesis and secretion of all classes of immunoglobulin. The magnitude of this response is similar to that seen with other polyclonal B cell activators such as pokeweed mitogen (PWM), and like that of PWM, the steroid effect is dependent on both T cells and monocytes. To determine the cellular target for GCS in these cultures, separated populations of T cells and non-T cells were preincubated with steroids and then recombined. No immunoglobulin was produced in any of these preincubation experiments. As a different approach to this question, supernatants were collected from various cell populations following stimulation with PWM, concanavalin A (Con A), phytohemagglutinin (PHA), alloantigens, or GCS. These supernatants were tested for their effects on GCS-induced Ig production by B cells. Supernatants from 3-d cultures of unstimulated, as well as GCS-treated, PBMC contained a T cell-replacing factor that permitted T-depleted PBMC to produce Ig upon steroid stimulation. This supernatant factor (TRF-S) could be produced in the absence of steroid stimulation, but both the factor and GCS were necessary for the induction of Ig synthesis. Production of the TRF-S required the presence of both T cells and adherent cells in culture and was found in the highest concentrations at 3-4 d of culture. Supernatants from cultures stimulated with PWM, PHA, Con A, and alloantigens did not contain detectable TRF-S activity, and TRF-S was unable to replace helper T cells for PWM-induced Ig production. TRF-S required the presence of adherent cells in the T cell-depleted responder population for its action. Further, it was effective in inducing Ig production along with GCS in the presence of a sufficient concentration of cyclosporin A to block all T cell helper activity for primary responses of PBMC to PWM or GCS. TRF-S was inactivated by trypsin treatment, heating to 56 degrees C, freezing, lyophilization, and storage at 4 degrees C for greater than 3 wk. Its molecular weight is probably 10,000 daltons or more, since TRF-S activity is not rapidly dialyzable. These experiments indicate that GCS-induced Ig production by human B cells does not require the presence of intact T cells in the cultures and therefore the steroids are not exerting their influence directly on T suppressor or T helper cells. Furthermore, they demonstrate a previously unrecognized cytokine that induces the differentiation of human B cells to Ig production in the presence of GCS.