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Effects of Intravenous Ketamine on Explicit and Implicit Measures of Suicidality in Treatment-Resistant Depression
Background
Intravenous ketamine has shown rapid antidepressant effects in early trials, making it a potentially attractive candidate for depressed patients at imminent risk of suicide. The Implicit Association Test (IAT), a performance-based measure of association between concepts, may have utility in suicide assessment.
Methods
Twenty-six patients with treatment-resistant depression were assessed using the suicidality item of the Montgomery-Asberg Depression Rating Scale (MADRS-SI) 2 hours before and 24 hours following a single subanesthetic dose of intravenous ketamine. Ten patients also completed IATs assessing implicit suicidal associations at comparable time points. In a second study, nine patients received thrice-weekly ketamine infusions over a 12-day period.
Results
Twenty-four hours after a single infusion, MADRS-SI scores were reduced on average by 2.08 points on a 0 to 6 scale (p < .001; d = 1.37), and 81% of patients received a rating of 0 or 1 postinfusion. Implicit suicidal associations were also reduced following ketamine (p = .003; d = 1.36), with reductions correlated across implicit and explicit measures. MADRS-SI reductions were sustained for 12 days by repeated-dose ketamine (p < .001; d = 2.42).
Conclusions
These preliminary findings support the premise that ketamine has rapid beneficial effects on suicidal cognition and warrants further study.Psycholog
Effects of Intravenous Ketamine on Explicit and Implicit Measures of Suicidality in Treatment-Resistant Depression
Background
Intravenous ketamine has shown rapid antidepressant effects in early trials, making it a potentially attractive candidate for depressed patients at imminent risk of suicide. The Implicit Association Test (IAT), a performance-based measure of association between concepts, may have utility in suicide assessment.
Methods
Twenty-six patients with treatment-resistant depression were assessed using the suicidality item of the Montgomery-Asberg Depression Rating Scale (MADRS-SI) 2 hours before and 24 hours following a single subanesthetic dose of intravenous ketamine. Ten patients also completed IATs assessing implicit suicidal associations at comparable time points. In a second study, nine patients received thrice-weekly ketamine infusions over a 12-day period.
Results
Twenty-four hours after a single infusion, MADRS-SI scores were reduced on average by 2.08 points on a 0 to 6 scale (p < .001; d = 1.37), and 81% of patients received a rating of 0 or 1 postinfusion. Implicit suicidal associations were also reduced following ketamine (p = .003; d = 1.36), with reductions correlated across implicit and explicit measures. MADRS-SI reductions were sustained for 12 days by repeated-dose ketamine (p < .001; d = 2.42).
Conclusions
These preliminary findings support the premise that ketamine has rapid beneficial effects on suicidal cognition and warrants further study.Psycholog
Job Satisfactions of Quantity Surveyors in Building Construction Firms in Dar-Es-Salaam, Tanzania
Human resource is the key component for any organizationâs success. It is crucial for organization to manage their human resources effectively and to their satisfaction, so that they stay longer without leaving the organization. Job satisfaction is identified as one of the factor that causes turnover intention of human resources in any organization. The study evaluates the job satisfaction of quantity surveyors in building construction firms of Dar-Es-salaam, Tanzania; with objectives being; to identify factors influencing job satisfaction; to determine level of job satisfaction; and to recommend interventions that can be applied to improve job satisfaction of quantity surveyors in building construction firms. The study considered a descriptive design where quantity surveyors employed by Class I to IV building construction firms were used, as a unit of analysis. In collecting data, a total of 55 questionnaires were distributed, whereby 42 were returned. Quantitative data were analyzed using Statistical Package for Social Sciences (SPSS), while qualitative data were analyzed thematically. The study revealed the major factors influencing job satisfaction of quantity surveyors, in order of importance, which includes; the working condition; organization commitment; pay; self-satisfaction of work done; job recognition; appreciation; relationship with co-workers; training and development opportunities; job security; job feedback; and job involvement in decision making and responsibilities. Furthermore, findings indicated that; the overall level of job satisfaction of quantity surveyors in building construction firms, is an average level of satisfaction with the mean score value of 3.02 and mode of 4.00. Moreover, it revealed that; quantity surveyors in building construction firm, have low level satisfaction in terms of job involvement in decision making and responsibilities; feedback and communication; job security; level of supervision; training and development opportunities; and the companyâs promotion policies. Various interventions recommended to improve job satisfaction of quantity surveyors in building construction firms includes; adequate recognition of the work by the quantity surveyors in the construction firms should be fully appreciated, and encroachment by other professionals should be highly discouraged. Advancement opportunity in career progression and professional development should be encouraged to improve quality service delivery. The work to be done by quantity surveyors should have clear goals, while objectives and interference by other professionals should be checked
Extreme population inversion in the fragments formed by UV photoinduced S-H bond fission in 2-thiophenethiol
H atom loss following near ultraviolet photoexcitation of gas phase 2-thiophenethiol molecules has been studied experimentally, by photofragment translational spectroscopy (PTS) methods, and computationally, by ab initio electronic structure calculations. The long wavelength (277.5 ℠λphot â„ 240 nm) PTS data are consistent with SâH bond fission after population of the first 1ÏÏ* state. The partner thiophenethiyl (R) radicals are formed predominantly in their first excited Ă2AâČ state, but assignment of a weak signal attributable to H + R([X with combining tilde]2AâČâČ) products allows determination of the SâH bond strength, D0 = 27 800 ± 100 cmâ1 and the Ăâ[X with combining tilde] state splitting in the thiophenethiyl radical (ÎE = 3580 ± 100 cmâ1). The deduced population inversion between the Ă and [X with combining tilde] states of the radical reflects the non-planar ground state geometry (wherein the SâH bond is directed near orthogonal to the ring plane) which, post-photoexcitation, is unable to planarise sufficiently prior to bond fission. This dictates that the dissociating molecules follow the adiabatic fragmentation pathway to electronically excited radical products. Ï* â Ï absorption dominates at shorter excitation wavelengths. Coupling to the same 1ÏÏ* potential energy surface (PES) remains the dominant dissociation route, but a minor yield of H atoms attributable to a rival fragmentation pathway is identified. These products are deduced to arise via unimolecular decay following internal conversion to the ground (S0) state PES via a conical intersection accessed by intra-ring CâS bond extension. The measured translational energy disposal shows a more striking change once λphot †220 nm. Once again, however, the dominant decay pathway is deduced to be SâH bond fission following coupling to the 1ÏÏ* PES but, in this case, many of the evolving molecules are deduced to have sufficiently near-planar geometries to allow passage through the conical intersection at extended SâH bond lengths and dissociation to ground ([X with combining tilde]) state radical products. The present data provide no definitive evidence that complete ring opening can compete with fast SâH bond fission following near UV photoexcitation of 2-thiophenethiol
A 1-acetamido derivative of 6-epi-valienamine: an inhibitor of a diverse group of ÎČ-N-acetylglucosaminidases
The synthesis of an analogue of 6-epi-valienamine bearing an acetamido group and its characterisation as an inhibitor of ÎČ-N-acetylglucosaminidases are described. The compound is a good inhibitor of both human O-GlcNAcase and human ÎČ-hexosaminidase, as well as two bacterial ÎČ-N-acetylglucosaminidases. A 3-D structure of the complex of Bacteroides thetaiotaomicron BtGH84 with the inhibitor shows the unsaturated ring is surprisingly distorted away from its favoured solution phase conformation and reveals potential for improved inhibitor potency
Curved grating fabrication techniques for concentric-circle grating, surface-emitting semiconductor lasers
We describe the fabrication and operational characteristics of a novel, surface-emitting semiconductor laser that makes use of a concentric-circle grating to both define its resonant cavity and to provide surface emission. A properly fabricated circular grating causes the laser to operate in radially inward- and outward-going circular waves in the waveguide, thus, introducing the circular symmetry needed for the laser to emit a beam with a circular cross-section. The basic circular-grating-resonator concept can be implemented in any materials system; an AlGaAs/GaAs graded-index, separate confinement heterostructure (GRINSCH), single-quantum-well (SQW) semiconductor laser, grown by molecular beam epitaxy (MBE), was used for the experiments discussed here. Each concentric-circle grating was fabricated on the surface of the AlGaAs/GaAs semiconductor laser. The circular pattern was first defined by electron-beam (e-beam) lithography in a layer of polymethylmethacrylate (PMMA) and subsequently etched into the semiconductor surface using chemically-assisted (chlorine) ion-beam etching (CAIBE). We consider issues that affect the fabrication and quality of the gratings. These issues include grating design requirements, data representation of the grating pattern, and e-beam scan method. We provide examples of how these techniques can be implemented and their impact on the resulting laser performance. A comparison is made of the results obtained using two fundamentally different electron-beam writing systems. Circular gratings with period lambda = 0.25 microns and overall diameters ranging from 80 microns to 500 microns were fabricated. We also report our successful demonstration of an optically pumped, concentric-circle grating, semiconductor laser that emits a beam with a far-field divergence angle that is less than one degree. The emission spectrum is quite narrow (less than 0.1 nm) and is centered at wavelength lambda = 0.8175 microns
The defining DNA methylation signature of Floating-Harbor Syndrome
Floating-Harbor syndrome (FHS) is an autosomal dominant genetic condition characterized by short stature, delayed osseous maturation, expressive language impairment, and unique facial dysmorphology. We previously identified mutations in the chromatin remodeling protein SRCAP (SNF2-related CBP Activator Protein) as the cause of FHS. SRCAP has multiple roles in chromatin and transcriptional regulation; however, specific epigenetic consequences of SRCAP mutations remain to be described. Using high resolution genome-wide DNA methylation analysis, we identified a unique and highly specific DNA methylation epi-signature in the peripheral blood of individuals with FHS. Both hyper and hypomethylated loci are distributed across the genome, preferentially occurring in CpG islands. Clonal bisulfite sequencing of two hypermethylated (FIGN and STPG2) and two hypomethylated (MYO1F and RASIP1) genes confirmed these findings. The identification of a unique methylation signature in FHS provides further insight into the biological function of SRCAP and provides a unique biomarker for this disorder
The first NINDS/NIBIB consensus meeting to define neuropathological criteria for the diagnosis of chronic traumatic encephalopathy.
Chronic traumatic encephalopathy (CTE) is a neurodegeneration characterized by the abnormal accumulation of hyperphosphorylated tau protein within the brain. Like many other neurodegenerative conditions, at present, CTE can only be definitively diagnosed by post-mortem examination of brain tissue. As the first part of a series of consensus panels funded by the NINDS/NIBIB to define the neuropathological criteria for CTE, preliminary neuropathological criteria were used by 7 neuropathologists to blindly evaluate 25 cases of various tauopathies, including CTE, Alzheimer's disease, progressive supranuclear palsy, argyrophilic grain disease, corticobasal degeneration, primary age-related tauopathy, and parkinsonism dementia complex of Guam. The results demonstrated that there was good agreement among the neuropathologists who reviewed the cases (Cohen's kappa, 0.67) and even better agreement between reviewers and the diagnosis of CTE (Cohen's kappa, 0.78). Based on these results, the panel defined the pathognomonic lesion of CTE as an accumulation of abnormal hyperphosphorylated tau (p-tau) in neurons and astroglia distributed around small blood vessels at the depths of cortical sulci and in an irregular pattern. The group also defined supportive but non-specific p-tau-immunoreactive features of CTE as: pretangles and NFTs affecting superficial layers (layers II-III) of cerebral cortex; pretangles, NFTs or extracellular tangles in CA2 and pretangles and proximal dendritic swellings in CA4 of the hippocampus; neuronal and astrocytic aggregates in subcortical nuclei; thorn-shaped astrocytes at the glial limitans of the subpial and periventricular regions; and large grain-like and dot-like structures. Supportive non-p-tau pathologies include TDP-43 immunoreactive neuronal cytoplasmic inclusions and dot-like structures in the hippocampus, anteromedial temporal cortex and amygdala. The panel also recommended a minimum blocking and staining scheme for pathological evaluation and made recommendations for future study. This study provides the first step towards the development of validated neuropathological criteria for CTE and will pave the way towards future clinical and mechanistic studies
Inhaled PGE1 in neonates with hypoxemic respiratory failure: two pilot feasibility randomized clinical trials.
BackgroundInhaled nitric oxide (INO), a selective pulmonary vasodilator, has revolutionized the treatment of neonatal hypoxemic respiratory failure (NHRF). However, there is lack of sustained improvement in 30 to 46% of infants. Aerosolized prostaglandins I2 (PGI2) and E1 (PGE1) have been reported to be effective selective pulmonary vasodilators. The objective of this study was to evaluate the feasibility of a randomized controlled trial (RCT) of inhaled PGE1 (IPGE1) in NHRF.MethodsTwo pilot multicenter phase II RCTs are included in this report. In the first pilot, late preterm and term neonates with NHRF, who had an oxygenation index (OI) of â„15 and <25 on two arterial blood gases and had not previously received INO, were randomly assigned to receive two doses of IPGE1 (300 and 150 ng/kg/min) or placebo. The primary outcome was the enrollment of 50 infants in six to nine months at 10 sites. The first pilot was halted after four months for failure to enroll a single infant. The most common cause for non-enrollment was prior initiation of INO. In a re-designed second pilot, co-administration of IPGE1 and INO was permitted. Infants with suboptimal response to INO received either aerosolized saline or IPGE1 at a low (150 ng/kg/min) or high dose (300 ng/kg/min) for a maximum duration of 72 hours. The primary outcome was the recruitment of an adequate number of patients (nâ=â50) in a nine-month-period, with fewer than 20% protocol violations.ResultsNo infants were enrolled in the first pilot. Seven patients were enrolled in the second pilot; three in the control, two in the low-dose IPGE1, and two in the high-dose IPGE1 groups. The study was halted for recruitment futility after approximately six months as enrollment targets were not met. No serious adverse events, one minor protocol deviation and one pharmacy protocol violation were reported.ConclusionsThese two pilot RCTs failed to recruit adequate eligible newborns with NHRF. Complex management RCTs of novel therapies for persistent pulmonary hypertension of the newborn (PPHN) may require novel study designs and a longer period of time from study approval to commencement of enrollment.Trial registrationCLINICALTRIALS.GOV: Pilot one: NCT number: 00598429 registered on 10 January 2008. Last updated: 3 February 2011. Pilot two: NCT number: 01467076 17 October 2011. Last updated: 13 February 2013
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