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Ketamine has emerged as a novel therapeutic agent for major depressive episodes, spurring interest in its potential to augment electroconvulsive therapy (ECT).
We sought to update our preliminary systematic review and meta-analysis, focusing on randomised controlled trials (RCTs) involving an index course of ECT, and testing the hypothesis that lack of efficacy is due to barbiturate anaesthetic co-administration.
We searched EMBASE, CENTRAL and Medline to identify RCTs examining the efficacy of ketamine during a course of ECT. Data were synthesised from ten trials (ketamine group n = 333, comparator group n = 269) using pooled random effects models.
Electroconvulsive therapy with ketamine was not associated with greater improvements in depressive symptoms or higher rates of clinical response or remission, nor did it result in pro-cognitive effects. This held true when limiting analysis to trials without barbiturate anaesthetic co-administration. Increased rates of confusion were reported.
Overall, our analyses do not support using ketamine over other induction agents in ECT.
Since 2004 there has been mounting evidence of the severe impact of introduced house mice (Mus musculus L.) killing chicks of burrow-nesting petrels at Gough Island. We monitored seven species of burrow-nesting petrels in 2014 using a combination of infra-red video cameras augmented by burrowscope nest inspections. All seven camera-monitored Atlantic petrel (Pterodroma incerta Schlegel) chicks were killed by mice within hours of hatching (average 7.2±4.0 hours) with an 87% chick failure rate (n=83 hatchlings). Several grey petrel (Procellaria cinerea Gmelin) chicks were found with mouse wounds and 60% of chicks failed (n=35 hatchlings). Video surveillance revealed one (of seven nests filmed) fatal attack on a great shearwater (Puffinus gravis O’Reilly) chick and two (of nine) on soft-plumaged petrel (Pterodroma mollis Gould) chicks. Mice killed the chicks of the recently discovered summer-breeding MacGillivray’s prion (Pachyptila macgillivrayi Mathews), with a chick mortality rate of 82% in 2013/14 and 100% in 2014/15. The closely-related broad-billed prion (P. vittata Forster) breeds in late winter and also had a chick mortality rate of 100% in 2014. The results provide further evidence of the dire situation for seabirds nesting on Gough Island and the urgent need for mouse eradication.
To explore the risk of suicide associated with occupation while evaluating the impact of socio-economic, demographic and psychiatric differences.
A nested case–control study with 3195 suicides and 63 900 matched controls. Information on causes of death, occupation, psychiatric admission, marital status and socio-economic factors was obtained from routine registers.
Across the 55 occupations investigated, the risk of suicide ranged from 2·73 [95% confidence interval (CI) 1·77–4·22] among doctors to 0·44 (95% CI 0·27–0·72) among architects and engineers compared with primary school teachers. With the exception of doctors and nurses, most of the excess risk of suicide associated with particular occupations is explained by the social and economic characteristics of people in those occupations. Much, but not all, of the excess risk in doctors and nurses is due to their increased use of self-poisoning, a method for which they have the knowledge to use effectively. Occupation has little association with suicide among people who suffer from a psychiatric illness, except for doctors, where the excess risk is 3·62 (p=0·007).
Most of the considerable variation in suicide risk across occupations is explained by socio-economic factors, except for doctors and nurses. Apart from in doctors, the risk of suicide has little association with occupation among people who suffer from a psychiatric illness. Restriction of access to lethal means is an important strategy in suicide prevention.
Ron J. Anderson, President and Chief Executive Officer Parkland Health and Hospital System,
Sue Pickens, Director of Strategic Planning and Population Medicine Parkland Health and Hospital System,
Enriqueta C. Bond, President The Burroughs Wellcome Fund,
Peter O. Kohler, President Oregon Health & Science University,
Robert Galvin, Director Global Healthcare at General Electric Company
Health care spending in the United States is massive and on the rise. We do not, however, spend our health care dollars wisely. Despite the importance of health and health care to individual, community, and national productivity, we have not designed a health system that assiduously leverages its resources to maximize health. Rather, we continue to support a health care system that does not provide access to basic care for all citizens and does not fully exploit either established knowledge or technologies proven to improve health.
Our health care spending and policy is heavily skewed towards treating rather than preventing illness (leading to higher treatment costs). We overemphasize the care of individuals to the detriment of the health of populations. We do not organize our practice systems to manage chronic illnesses as well as we could. Quality and safety of care are highly variable; both over-treatment and under-treatment are commonplace. Such practices waste dollars and patient time and expose patients to unnecessary risk. Typically, incentives are not aligned with desired behaviors of patients and health professionals. Further, administrative costs are high and regulations are often beside the mark. In short, we must make substantial reforms.
The Blue Ridge Academic Health Group (Blue Ridge Group) believes that it is both possible and essential for the United States to spend its health care dollars much more rationally and effectively. We can build a true health system that is capable of maximizing the health of individuals and populations.
To determine whether reprocessed single-use devices would meet regulatory standards for sterility and meet the same materials standards as a new device.
The study included single-use and reusable biopsy forceps and papillotomes and a reusable stone retrieval basket. The suitability of these devices for cleaning and disinfection or sterilization was examined.
Testing of cleanability was conducted on devices contaminated with technetium 99-radiolabeled human blood. Instruments were cleaned using hospital recommended practices for manual cleaning. Gamma counts per second were determined before and after cleaning to localize contaminants, which were additionally visualized using light and scanning electron microscopy. X-ray phc-toelectron spectroscopy was used to quantify contamination elements on the materials tested. Residual bioburden testing on instruments contaminated with microorganisms suspended in coagulable sheep blood was carried out to establish the efficacy of disinfection and sterilization.
All devices remained contaminated after cleaning, but single-use devices and the stone basket tended to be more heavily contaminated than reusable forceps and papillotomes. Cleaning procedures facilitated distribution of contaminants further into the lumens of the disposable forceps. Decreased concentrations of silicon and increased concentrations of carbon and nitrogen suggested that layers of silicon lubricant had been removed and contaminants were organic material. Reusable devices were effectively disinfected, but single-use devices were not Sterilization could not eliminate the challenge microorganisms completely.
None of the reprocessed single-use instruments were effectively cleaned, disinfected, or sterilized. This condition may provide an opportunity for the viability of non-resistant or nosocomial organisms and viruses. Additionally, reprocessing procedures may result in material destruction of fragile devices. Cost-saving initiatives that have inspired reprocessing of single-use devices, despite the absence of data establishing the efficacy of decontamination and the durability of materials throughout reprocessing, should be pushed into the background.
How neurons in the primary visual cortex (V1) of
primates process parallel inputs from the magnocellular
(M) and parvocellular (P) layers of the lateral geniculate
nucleus (LGN) is not completely understood. To investigate
whether signals from the two pathways are integrated in
the cortex, we recorded contrast-response functions (CRFs)
from 20 bush baby V1 neurons before, during, and after
pharmacologically inactivating neural activity in either
the contralateral LGN M or P layers. Inactivating the M
layer reduced the responses of V1 neurons (n =
10) to all stimulus contrasts and significantly elevated
(t = 8.15, P < 0.01) their average
contrast threshold from 8.04 (± 4.1)% contrast to
22.46 (± 6.28)% contrast. M layer inactivation also
significantly reduced (t = 4.06, P <
0.01) the average peak response amplitude. Inactivating
the P layer did not elevate the average contrast threshold
of V1 neurons (n = 10), but significantly reduced
(t = 4.34, P < 0.01) their average
peak response amplitude. These data demonstrate that input
from the M pathway can account for the responses of V1
neurons to low stimulus contrasts and also contributes
to responses to high stimulus contrasts. The P pathway
appears to influence mainly the responses of V1 neurons
to high stimulus contrasts. None of the cells in our sample,
which included cells in all output layers of V1, appeared
to receive input from only one pathway. These findings
support the view that many V1 neurons integrate information
about stimulus contrast carried by the LGN M and P pathways.
Exposure of Fucus spiralis germlings to precise copper concentrations (0 to 844 nM
Cu2+) in chemically defined medium demonstrated a
relationship between ultrastructural changes and growth retardation with
increasing copper concentration. Electron-translucent vesicles,
present in ova, which normally disappear after fertilization, accumulated
in germlings exposed to Cu2+ above 10·6 nM, suggesting that
copper may inhibit a metabolic pathway involved in cell wall formation which
is initiated by fertilization. No membrane damage was
observed during the exposure period. During a post-exposure period in copper-free
medium, recovery occurred (rhizoid extension, apical
hair formation) in germlings previously exposed to concentrations below 106 nM Cu2+
and electron-translucent vesicles became granular
and disappeared. It is proposed that the electron-translucent vesicles contain a cell wall
precursor and that copper inhibits its incorporation
into the cell wall, preventing growth and development of the zygote.
We used deep HST imaging of three LMC clusters, NGC 2257, NGC 1466 and Hodge 11, to determine their ages relative to Milky Way clusters. They all have similar ages to within ± 1 Gyr. For NGC 2257 and NGC 1466, we measured the blue straggler specific frequencies and find them to be similar to those of Galactic clusters.
In designing automated systems for interpretation of micrographs, it is often the goal to separate and discern various objects within the image data. After segmentation, measurements of the objects, called features, can then be calculated and used for process or statistical analysis. Simple segmentation schemes based on single threshold operations, often lack the sophistication to deal with intricate or subtle details of the image data, or require user intervention in the threshold selection process. This talk will present and discuss advanced techniques which adapt to the data, and which can operate autonomously without human supervision.
Segmentation is a process which transforms pixel based image data into symbolic descriptors representing groups of pixel elements. These descriptors are called objects and take the form of lines, regions, polygons, points, windows of interests, or other unique representations. Most laboratory image analysis software packages utilize segmentation schemes based on the principle of intensity analysis.
Modem technical imaging devices acquire digital image data at a precision level that often exceeds that of available display technologies so that parts of the data information may not be revealed in the displayed image. Data resolution and display resolution are closely related to image information and digital image processing provides several useful tools for compensation of such display deficiencies.
Typical precision data may be captured by a CCD camera, a scanning microscope or flatbed digitizer from photographic film and may exceed a size of 1,000×1,000 data points and a data point depth of 12 bit. Digital data has two general characteristics that deal with spatial resolution and intensity resolution. The distance represented between data points determines the spatial data resolution. Equally important is the bit-resolution which describes the maximum number of intensity levels possible in each point.
Human α2 macroglobulin (α2M) has structural and functional properties that contribute to its uniqueness as proteinase inhibitor. It is the largest known (Mr=720,000) and the only natural proteinase inhibitor which has a broad range of reactivity and for which the reaction is irreversible. It has a vital role in the clearance of proteinases from the circulation and in regulating their activity in fibrinolysis, coagulation and complement activation.
An α2M molecule can entrap two proteinase molecules such as chymotrypsin and trypsin and can therefore be considered to contain two functional domains. Each subunit in the homotetramer has a bait region with cleavage sites for nearly all known endoproteinases and an internal thiol ester bond. A proteinase cleaves the two bait regions within both functional units leading to an activation and cleavage of the thiol ester bonds. Consequently, α2M undergoes a major structural change resulting in the irreversible entrapment of the proteinase.
There are no “absolutes” in terms of performance and wherever possible, performance measures need to reflect conditions similar to those in the intended application. Unfortunately, measurements are frequently constrained by practical and economic considerations. For example, the most convenient radiation source for testing EDX systems is the Fe55 radioactive source which produces Mn Kα radiation at 5.9keV and can be used with an air path between source and detector. However, the fwhm resolution at 5.9keV is a rather poor measure of what the resolution will be for x-ray energies below 0.5 keV. Furthermore, “P/B”, the ratio of Mn Kα peak height to background level at IkeV, is only a crude indication of incomplete charge collection ICC, and does not reveal problems that may give rise to shift and broadening of the C Kα peak for example.
A major reason for performing microanalysis in the Field-Emission Gun Scanning Transmission Electron Microscope (FEG-STEM) is the very high spatial resolution of the information obtained. It has been estimated that in ideal cases, energy-dispersive x-ray analysis in such an instrument can provide 0.1 wt.% detection sensitivity for an element in a region about 1.5nm in diameter of a foil about 30nm thick. It is obvious that such performance requires that the instrument be properly adjusted, and hence that the probe-forming characteristics be fully understood.
There are three fundamental limits on the minimum size of an electron probe, these being i) the geometrical demagnification of the source, ii) diffraction at the beam-limiting aperture, and iii) spherical aberration in the probe-forming lens. In addition, misalignment of the beam-limiting aperture will result in probe aberrations.
Palladium based catalyst have technological applications in catalytic converters in automobile industry for the combustion of NOx and CO gasses. Pd can also adsorb up to 900 times its volume H2 and is useful for purifying H2. Electron holography studies with model Pd on silica catalysts  show that under some circumstances, the Pd particles may form voids. The reason for the formation of these voids and the conditions under which they are formed are not well understood. We have done in situ and ex situ studies on oxidation and reduction of similar model Pd/SiO2 to develop a better understanding of the conditions under which voids are formed.
The catalyst samples were prepared by impregnating silica with acetyl acetoneate (acac) and oxidizing in air and then reducing in H2 at 300°C . High resolution images (Fig. 1) of Pd particles show a central feature with low contrast attributed to the presence of voids.
We endorse Davey's view that expectancy processes are intimately involved in fear reactions, but question his model on three grounds. First, the mechanism for generating expectancy bias to both ontogenetic and phylogenetic stimuli is not spelled out. Second, the selective association component is unnecessary. Third, the model fails to provide a clear explanation for the irrationality of phobic reactions.
Research methods and knowledge in the field of male reproductive toxicology have gradually improved since reports in the late 1970s on severe impairment of spermatogenesis in workers with occupational exposure to certain chlorinated hydrocarbon pesticides (the nematocide 1,2-dibromochloropropan and the insecticide and fungicide chlordecone, but still we have only vague answers to basic questions about the overall significance of the environmental and occupational impact of these compounds on male reproductive capability.