Foreign body response to five common subcutaneous implants Ibrahim, Mohamed M., MD; Medina, Manuel A., MD; Bond, Jennifer E., PhD ...
Journal of the American College of Surgeons,
October 2015, Letnik:
221, Številka:
4
Journal Article
The serotypes of hepatitis B surface antigen present in patients at the Lynchburg Training School and Hospital were determined by counterelectrophoresis. Hepatitis B surface antigen was detected by ...counterelectrophoresis in 72 of 82 samples that were positive by complement fixation or passive hemagglutination techniques. Of the isolates that were serotyped, 51 (71%) were ad, and 21 (29%) were ay; thus the ad:ay ratio was about 2.4:1. The incidence of the ay serotype was significantly higher in females and in patients with Down's syndrome. The ay serotype was not randomly distributed in the institution but was clustered in two of seven female wards and four of 11 male wards, all of which contained younger patients who had been institutionalized at an early age.
We have used the WFPC2 camera on the Hubble Space Telescope to obtain
photometry of the outer-halo globular clusters Palomar 3, Palomar 4, and
Eridanus. These three are classic examples of the ..."second parameter" anomaly
because of their red horizontal-branch morphologies in combination with their
low-to-intermediate metallicities. Our color-magnitude diagrams in (V, V-I)
reach $V_{lim} \simeq 27.0$, clearly delineating the subgiant and turnoff
regions and about three magnitudes of the unevolved main sequences. The slopes
and dereddened colors of the giant branches are consistent with published
Fe/H estimates that rank the clusters (Pal 3, Eridanus, Pal 4) in order of
increasing metallicity, with all three falling near or between the abundance
values of the classic nearby halo clusters M3 and M5. Differential fits of
their color-magnitude diagrams are made to each other and to M3 and M5 for
relative age determinations. We find that the three outer-halo cluster CMDs
differ from the nearby clusters in a way that is consistent with their being
younger by $\sim 1.5 - 2 $Gyr, if we have correctly estimated the clusters'
chemical-abundance ratios. Conversely, the inferred age difference could be
smaller ($\ltsim 1 $Gyr) if either Fe/H or $\alpha$/Fe for the outer-halo
clusters is significantly lower than we have assumed. Possible age spreads of
order 1$ $Gyr among both the nearby and outer-halo clusters may also be
present.
We report results of an HST "snapshot" survey aimed at finding resolved binary companions of the central stars of Galactic planetary nebulae (PNe). Using WF/PC and WFPC2, we searched the fields of ...113 PNe for stars whose close proximity to the central star suggests a physical association. We find 10 binary nuclei that are very likely to be physically associated, and another six that are possible binary associations. By correcting for interstellar extinction and placing the central stars' companions on the main sequence, we derive distances to the objects, and thereby significantly increase the number of PNe with reliable distances. Comparison of our derived distances with those obtained from various statistical methods shows that all of the latter have systematically overestimated the distances, by factors ranging up to a factor of two or more. We show that this error is most likely due to the fact that the properties of our PNe with binary nuclei are systematically different from those of PNe used heretofore to calibrate statistical methods. Specifically, our PNe tend to have lower surface brightnesses at the same physical radius than the traditional calibration objects. This difference may arise from a selection effect: the PNe in our survey are typically nearby, old nebulae, whereas most of the objects that calibrate statistical techniques are low-latitude, high-surface-brightness, and more distant nebulae. As a result, the statistical methods that seem to work well with samples of distant PNe, e.g., those in the Galactic bulge or external galaxies, may not be applicable to the more diverse population of local PNe.
We present the discovery observations for the optical counterpart of the
$\gamma$-ray burster GRB 970508 and discuss its light curve in the context of
the fireball model. We analyze the HST data for ...this object, and conclude that
any underlying galaxy must be fainter than $R$ = 25.5. We also present a
detailed analysis of the HST images of GRB 970228 claimed to show a proper
motion of the optical counterpart and conclude that, within the uncertainties,
there is no proper motion. We examine several aspects of the neutron-star
merger model for $\gamma$-ray bursts. In particular, we use this model to
predict the redshift distribution of $\gamma$-ray bursters, and adopting a
recent determination of the cosmic star-formation history, we show that the
predicted distribution of $\log N - \log P$ relation is consistent with that
observed for GRBs.
Abstract
Background
A minority of patients presenting to hospital with COVID-19 have bacterial coinfection. Procalcitonin testing may help identify patients for whom antibiotics should be prescribed ...or withheld. The PEACH study describes the use of procalcitonin in English and Welsh hospitals during the first wave of the COVID-19 pandemic to help diagnose bacterial infections and guide antibiotic treatment. There is a lack of clear evidence to support its use in lung infections, which means in some hospitals, clinicians have used the procalcitonin test to guide antibiotic decisions in COVID-19, whilst in other hospitals, they have not. Our study is analysing data from hospitals that did and did not use procalcitonin testing during the first wave of the COVID-19 pandemic. It will determine whether and how procalcitonin testing should be used in the NHS in future waves of COVID-19 to protect patients from antibiotic overuse.
Methods
To assess whether the use of PCT testing, to guide antibiotic prescribing, safely reduced antibiotic use among patients who were hospitalized with COVID-19 during the first wave of the pandemic, we are answering this question through three different, and complimentary, work streams (WS), each with discrete work packages (WP): (i) Work Stream 1: utilization of PCT testing to guide antibiotic prescribing during the first wave of COVID-19 pandemic; (ii) Work Stream 2: patient-level impact of PCT testing on antibiotic exposure and clinical outcome (main work stream currently in analysis); and (iii) Work Stream 3: health economics analysis of PCT testing to guide antibiotics in COVID-19.
Results
Our first publication from Work Stream 1 (Antibiotics 2021, 10: 516) used a web-based survey to gather data from antimicrobial leads about the use of procalcitonin testing. Responses were received from 148/151 (98%) eligible hospitals. During the first wave of the COVID-19 pandemic, there was widespread introduction and expansion of PCT use in NHS hospitals. The number of hospitals using PCT in emergency/acute admissions rose from 17 (11%) to 74/146 (50.7%) and use in ICU increased from 70 (47.6%) to 124/147 (84.4%). This increase happened predominantly in March and April 2020, preceding NICE guidance. Approximately half of hospitals used PCT as a single test to guide decisions to discontinue antibiotics and half used repeated measurements. There was marked variation in the thresholds used for empirical antibiotic cessation and guidance about interpretation of values.
Conclusions
Procalcitonin testing has been widely adopted in the NHS during the COVID-19 pandemic in an unevidenced, heterogeneous way and in conflict with relevant NICE guidance. Further research is needed urgently that assesses the impact of this change on antibiotic prescribing and patient safety. Work Stream 2 is ongoing, and results will be published once available.
Astrophys.J.484:741-760,1997 Using WFPC2 on the Hubble Space Telescope, we have isolated a sample of 258
white dwarfs (WDs) in the Galactic globular cluster M4. Fields at three radial
distances from ...the cluster center were observed and sizeable WD populations
were found in all three. The location of these WDs in the color-magnitude
diagram, their mean mass of 0.51($ \pm 0.03$)M$_{\odot}$, and their luminosity
function confirm basic tenets of stellar evolution theory and support the
results from current WD cooling theory. The WDs are used to extend the cluster
main-sequence mass function upward to stars that have already completed their
nuclear evolution. The WD/red dwarf binary frequency in M4 is investigated and
found to be at most a few percent of all the main-sequence stars. The most
ancient WDs found are about 9 Gyr old, a level which is set solely by the
photometric limits of our data. Even though this is less than the age of M4, we
discuss how these cooling WDs can eventually be used to check the turnoff ages
of globular clusters and hence constrain the age of the Universe.
The nature of the components and some of the association forces in aggregated acetylcholinesterase, extracted from the electric organ of Electrophorus electricus, were investigated. The aggregated ...acetylcholinesterase (rapidly sedimenting, 70 S, and referred to as fast acetylcholinesterase) and the dissociated or “monomer” acetylcholinesterase (11.5 S and referred to as slow acetylcholinesterase) were isolated by zonal centrifugation. The fast acetylcholinesterase was further processed by gel filtration, resulting in a fast acetylcholinesterase of low specific activity and a slow acetylcholinesterase of high specific activity and a lowered sedimentation value (10.8 S). The fast acetylcholinesterase was exposed to the hydrolytic action of various enzymes (neuraminidase, hyaluronidase, alkaline phosphatase, and phospholipase A) and examined by sucrose gradient centrifugation techniques with no effect observed on the aggregation. However, phospholipases C and D and pancreatic lipase dissociated the fast acetylcholinesterase to the slow acetylcholinesterase (11.5 S). With phospholipase C, but not pancreatic lipase, the acetylcholinesterase was released from a matrix of ultraviolet absorbing, non‐enzymatic material which remained in its aggregated form. With pancreatic lipase the matrix was also dissociated into a “monomer” species with a sedimentation value similar to that of the “monomer” acetylcholinesterase (resembling dissociation in high ionic strength). The hydrolytic action of the lipases did not alter the sedimentation value of the “monomer” nor its property of reversibly forming a gelatinous precipitate at pH 4.0. However, the slow acetylcholinesterase recovered from the gel column was not sensitive to the acid pH. The results indicate that the aggregated or fast acetylcholinesterase is a complex between “monomer” and a matrix of lipoproteins which, in itself, is an aggregation of molecular species similar in sedimentation value to the “monomer” acetylcholinesterase. A model is presented. Comparison between the matrix and the receptor protein is made.
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