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Picoliter-volume inkjet printing into planar microdevice reservoirs for low-waste, high-capacity drug loading.
Oral delivery of therapeutics is the preferred route for systemic drug administration due to ease of access and improved patient compliance. However, many therapeutics suffer from low oral bioavailability due to low pH and enzymatic conditions, poor cellular permeability, and low residence time. Microfabrication techniques have been used to create planar, asymmetric microdevices for oral drug delivery to address these limitations. The geometry of these microdevices facilitates prolonged drug exposure with unidirectional release of drug toward gastrointestinal epithelium. While these devices have significantly enhanced drug permeability in vitro and in vivo, loading drug into the micron-scale reservoirs of the devices in a low-waste, high-capacity manner remains challenging. Here, we use picoliter-volume inkjet printing to load topotecan and insulin into planar microdevices efficiently. Following a simple surface functionalization step, drug solution can be spotted into the microdevice reservoir. We show that relatively high capacities of both topotecan and insulin can be loaded into microdevices in a rapid, automated process with little to no drug waste
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Timeshare Ownersâ Perceptions of and Preferred Ways of Participating in Tourism Planning
Purpose
To explore the impact of prostate cancer treatment on: (a) the experience of symptoms (i.e. sexual, urinary, and bowel), and (b) perceived health state of men with prostate cancer one month following their radiation treatment. Methods
A prospective pre-testâpost-test descriptive survey was conducted on a convenience sample of 73 men with prostate cancer who were recruited from a Regional Cancer Centre in Southwestern Ontario, Canada. Participants receiving radiation treatment (brachy therapy, high dose radiation [HDR] and external beam radiation [EBR], or EBR alone) completed a questionnaire that elicited information pertaining to quality of life (QOL), symptom experiences, and perceived health state prior to, and one month after completion of their radiation treatment. Results
Post-treatment scores showed increased problems with urinary bother (ppp=0.002) and function (p=0.001), and sexual function (p Discussion
Our findings suggest that prostate cancer treatment presents a challenge with regard to symptom experiences and perceived health state in men with prostate cancer. Therefore, strategies for patient education to assist men to cope with their symptoms and to provide them with support in the initial weeks following treatment are discussed
Structure and electronic properties of tin monoxide (SnO) and lithiated SnO terminated diamond (1 0 0) and its comparison with lithium oxide terminated diamond
The prevalence of hepatitis C virus among people of South Asian origin in Glasgow: results from a community based survey and laboratory surveillance
Background South Asians often present late with HCV or HBV related liver disease which could have been avoided with early diagnosis and subsequent treatment; however the prevalence of HCV/HBV among South Asians in Glasgow is not known. Accordingly, to inform the need for case finding among this group we aimed to examine the prevalence of Hepatitis C virus (HCV) among South Asians living in Glasgow. Methods A community-based survey recruited individuals at six mosques and four community centres serving the South Asian community during 2009-2010; participants had predominantly never been HCV tested. Laboratory surveillance data involving all individuals tested for HCV during 1993-2009 were examined and South Asians were identified using Nam Pehchan software. Results In the community-based survey, 2.6% of 1288 participants tested HCV-antibody positive; the prevalence ranged from 0.6% among those born in the UK to 3.1% among those born in Pakistan. The odds of testing HCV-antibody positive were significantly raised among those who had surgery in South Asia (aOR: 5.0, 95% CI: 2.0-12.3) and had either medical/dental treatment or an injection in South Asia (aOR: 2.2, 95% CI: 1.0-5.0). Of 6404 South Asians identified from laboratory surveillance data, 9.3% tested HCV positive. An estimated 38% (330/870) of HCV-infected South Asians living in Glasgow remain undiagnosed. Conclusions South Asians living in Glasgow, particularly those born outside the UK are at greater risk of HCV infection than the general population. Efforts to increase awareness and testing in this population are warranted.</p
An Upper Mass Limit on a Red Supergiant Progenitor for the Type II-Plateau Supernova SN 2006my
We analyze two pre-supernova (SN) and three post-SN high-resolution images of
the site of the Type II-Plateau supernova SN 2006my in an effort to either
detect the progenitor star or to constrain its properties. Following image
registration, we find that an isolated stellar object is not detected at the
location of SN 2006my in either of the two pre-SN images. In the first, an
I-band image obtained with the Wide-Field and Planetary Camera 2 on board the
Hubble Space Telescope, the offset between the SN 2006my location and a
detected source ("Source 1") is too large: > 0.08", which corresponds to a
confidence level of non-association of 96% from our most liberal estimates of
the transformation and measurement uncertainties. In the second, a similarly
obtained V-band image, a source is detected ("Source 2") that has overlap with
the SN 2006my location but is definitively an extended object. Through
artificial star tests carried out on the precise location of SN 2006my in the
images, we derive a 3-sigma upper bound on the luminosity of a red supergiant
that could have remained undetected in our pre-SN images of log L/L_Sun = 5.10,
which translates to an upper bound on such a star's initial mass of 15 M_Sun
from the STARS stellar evolutionary models. Although considered unlikely, we
can not rule out the possibility that part of the light comprising Source 1,
which exhibits a slight extension relative to other point sources in the image,
or part of the light contributing to the extended Source 2, may be due to the
progenitor of SN 2006my. Only additional, high-resolution observations of the
site taken after SN 2006my has faded beyond detection can confirm or reject
these possibilities.Comment: Minor text changes from Version 1. Appendix added detailing the
determination of confidence level of non-association of point sources in two
registered astronomical image
The BATSE-Swift luminosity and redshift distributions of short-duration GRBs
We compare the luminosity function and rate inferred from the BATSE short
hard bursts (SHBs) peak flux distribution with the redshift and luminosity
distributions of SHBs observed by Swift/HETE II. While the Swift/HETE II SHB
sample is incompatible with SHB population that follows the star formation
rate, it is compatible with a SHB rate that reflect a distribution of delay
times after the SFR. This would be the case if SHBs are associated with binary
neutron star mergers. The available data allows, however, different
interpretations. For example, a population whose rate is independent of the
redshift fits the data very well. The implied SHB rates that we find range from
to Gpcyr. This is a much higher rate
than what was previously estimated. A detailed (2 dimensional) look at the best
fit models shows, however, some discrepancy between the four Swift/HETE II SHBs
and the models based on BATSE SHBs. This could be a statistical fluke. It could
also arise from wrong estimates of the triggering criteria or from selection
effects. If real it may indicate the existence of two SHB populations with
different luminosity functions and redshift distributions.Comment: Revised version includes additional bursts and revised redshift of
older burst
Movement patterns and activity levels are shaped by the neonatal environment in Antarctic fur seal pups
This research was funded by the German Research Foundation (DFG) as part of the SFB TRR 212 (NC3)âProject Numbers 316099922, 396774617, and 396782756. It was also supported by core funding from the Natural Environment Research Council to the British Antarctic Surveyâs Ecosystems Program.Tracking studies of juveniles are rare compared to those of adults, and consequently little is known about the influence of intrinsic and extrinsic factors on activity during this critical life stage. We used hourly GPS data, collected from 66 Antarctic fur seal pups from birth until moulting, to investigate the explanatory power of multiple individual-based and environmental variables on activity levels. Pups were sampled from two nearby breeding colonies of contrasting density during two subsequent years, and a two-state hidden Markov model was used to identify modalities in their movement behaviour, specifically 'active' and 'inactive' states. We found that movement was typified by central place exploration, with active movement away from and subsequent return to a location of inactivity. The probability of such directed exploration was unaffected by several factors known to influence marine mammal movement including sex, body condition, and temperature. Compared to pups born at the high-density colony, pups at low-density were more active, increased their activity with age, and transitioned earlier into the tussock grass, which offers protection from predators and extreme weather. Our study illustrates the importance of extrinsic factors, such as colony of birth, to early-life activity patterns and highlights the adaptive potential of movement.Publisher PDFPeer reviewe
GRB070125: The First Long-Duration Gamma-Ray Burst in a Halo Environment
We present the discovery and high signal-to-noise spectroscopic observations
of the optical afterglow of the long-duration gamma-ray burst GRB070125. Unlike
all previously observed long-duration afterglows in the redshift range 0.5 < z
1.0 A) absorption
features in the wavelength range 4000 - 10000 A. The sole significant feature
is a weak doublet we identify as Mg II 2796 (W = 0.18 +/- 0.02 A), 2803 (W =
0.08 +/- 0.01) at z = 1.5477 +/- 0.0001. The low observed Mg II and inferred H
I column densities are typically observed in galactic halos, far away from the
bulk of massive star formation. Deep ground-based imaging reveals no host
directly underneath the afterglow to a limit of R > 25.4 mag. Either of the two
nearest blue galaxies could host GRB070125; the large offset (d >= 27 kpc)
would naturally explain the low column density. To remain consistent with the
large local (i.e. parsec scale) circum-burst density inferred from broadband
afterglow observations, we speculate GRB070125 may have occurred far away from
the disk of its host in a compact star-forming cluster. Such distant stellar
clusters, typically formed by dynamical galaxy interactions, have been observed
in the nearby universe, and should be more prevalent at z>1 where galaxy
mergers occur more frequently.Comment: 8 pages, accepted in Ap
GRB 070201: A possible Soft Gamma Ray Repeater in M31
The gamma-ray burst (GRB) 070201 was a bright short-duration hard-spectrum
GRB detected by the Inter-Planetary Network (IPN). Its error quadrilateral,
which has an area of 0.124 sq. deg, intersects some prominent spiral arms of
the nearby M31 (Andromeda) galaxy. Given the properties of this GRB, along with
the fact that LIGO data argues against a compact binary merger origin in M31,
this GRB is an excellent candidate for an extragalactic Soft Gamma-ray Repeater
(SGR) giant flare, with energy of 1.4x10^45 erg. Analysis of ROTSE-IIIb visible
light observations of M31, taken 10.6 hours after the burst and covering 42% of
the GRB error region, did not reveal any optical transient down to a limiting
magnitude of 17.1. We inspected archival and proprietary XMM-Newton X-ray
observations of the intersection of the GRB error quadrilateral and M31,
obtained about four weeks prior to the outburst, in order to look for periodic
variable X-ray sources. No SGR or Anomalous X-ray Pulsar (AXP) candidates
(periods in range 1 to 20 s) were detected. We discuss the possibility of
detecting extragalactic SGRs/AXPs by identifying their periodic X-ray light
curves. Our simulations suggest that the probability of detecting the periodic
X-ray signal of one of the known Galactic SGRs/AXPs, if placed in M31, is about
10% (50%), using 50 ks (2 Ms) XMM-Newton exposures.Comment: 7 pages, submitted to ApJ (Fig. 2 resolution reduced
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