272 research outputs found
A deep submillimetre survey of the Galactic Centre
We present first results from a submillimetre continuum survey of the
Galactic Centre `Central Molecular Zone' (CMZ), made with SCUBA on the James
Clerk Maxwell Telescope. SCUBA's scan-map mode has allowed us to make extremely
wide-field maps of thermal dust emission with unprecedented speed and
sensitivity. We also discuss some issues related to the elimination of
artefacts in scan-map data. Our simultaneous 850/450 micron maps have a total
size of approximately 2.8 x 0.5 degrees (400 x 75 pc) elongated along the
galactic plane. They cover the Sgr A region-including Sgr A*, the circumnuclear
disc, and the +20 km/s and +50 km/s clouds; the area around the Pistol; Sgr
B2-the brightest feature on the map; and at their Galactic Western and Eastern
edges the Sgr C and Sgr D regions. There are many striking features such as
filaments and shell-like structures, as well as point sources such as Sgr A*
itself. The total mass in the Central Molecular Zone is greater than that
revealed in previous optically-thin molecular line maps by a factor of ~3, and
new details are revealed on scales down to 0.33 pc across this 400 pc wide
region.Comment: 12 pages, 3 figures, (figures now smaller, in paper body), accepted
by ApJ
Phase II Trial of IL-12 Plasmid Transfection and PD-1 Blockade in Immunologically Quiescent Melanoma.
PurposeTumors with low frequencies of checkpoint positive tumor-infiltrating lymphocytes (cpTIL) have a low likelihood of response to PD-1 blockade. We conducted a prospective multicenter phase II trial of intratumoral plasmid IL-12 (tavokinogene telseplasmid; "tavo") electroporation combined with pembrolizumab in patients with advanced melanoma with low frequencies of checkpoint positive cytotoxic lymphocytes (cpCTL).Patients and methodsTavo was administered intratumorally days 1, 5, and 8 every 6 weeks while pembrolizumab (200 mg, i.v.) was administered every 3 weeks. The primary endpoint was objective response rate (ORR) by RECIST, secondary endpoints included duration of response, overall survival and progression-free survival. Toxicity was evaluated by the CTCAE v4. Extensive correlative analysis was done.ResultsThe combination of tavo and pembrolizumab was well tolerated with adverse events similar to those previously reported with pembrolizumab alone. Patients had a 41% ORR (n = 22, RECIST 1.1) with 36% complete responses. Correlative analysis showed that the combination enhanced immune infiltration and sustained the IL-12/IFNγ feed-forward cycle, driving intratumoral cross-presenting dendritic cell subsets with increased TILs, emerging T cell receptor clones and, ultimately, systemic cellular immune responses.ConclusionsThe combination of tavo and pembrolizumab was associated with a higher than expected response rate in this poorly immunogenic population. No new or unexpected toxicities were observed. Correlative analysis showed T cell infiltration with enhanced immunity paralleling the clinical activity in low cpCTL tumors
The physiological disposition and metabolic fate of cortisone in
In an earlier paper we described studies on the physiological disposition and metabolic fate of hydrocortisone in man (1). This paper describes similar studies on cortisone. Although contributing very little to the body pool of adrenal cortical steroids, cortisone has been used extensively as a therapeutic agent, and it was therefore of interest to compare its metabolism with that of hydrocortisone. Large doses of cortisone and hydrocortisone were administered intravenously and rates of disappearance from the plasma determined in normal subjects and in patients with liver disease, myxedema, thyrotoxicosis, and rheumatoid arthritis. Trace quantities of cortisone-4-C" and hydrocortisone-4-C" were employed in certain studies. From these studies, information was obtained regarding rate of metabolic transformation, rate of absorption, rates and routes of excretion of cortisone and its metabolites, and, to some extent, the identity and amount of these metabolites. Information was also obtained on the in vivo conversion of cortisone to hydrocortisone. MATERIALS AND METHODS Administration of steroid. The steroids were dissolved in 25 ml. ethanol and added to 500 ml. of sterile five per cent dextrose in water. This solution was administered intravenously over a period of 10 to 20 minutes. For oral or intramuscular administration the steroids were suspended in saline. Cortisone-4-C" was administered intravenously in trace quantities in a small volume of five per cent ethanol in water over a period of 3 to 5 minutes, or mixed with carrier cortisone and given in 500 ml. of three per cent ethanol in five per cent dextrose in sterile distilled water. Following the administration of the steroids, blood samples were drawn in heparinized syringes every 20 or 30 minutes for 2 hours-or more. Urine samples were collected and preserved by freezing. Methods of assay. The extraction procedures for the steroids in plasma and urine were the same as those de
Activation of the dopamine 1 and dopamine 5 receptors increase skeletal muscle mass and force production under non-atrophying and atrophying conditions
<p>Abstract</p> <p>Background</p> <p>Control of skeletal muscle mass and force production is a complex physiological process involving numerous regulatory systems. Agents that increase skeletal muscle cAMP levels have been shown to modulate skeletal muscle mass and force production. The dopamine 1 receptor and its closely related homolog, the dopamine 5 receptor, are G-protein coupled receptors that are expressed in skeletal muscle and increase cAMP levels when activated. Thus we hypothesize that activation of the dopamine 1 and/or 5 receptor will increase skeletal muscle cAMP levels thereby modulating skeletal muscle mass and force production.</p> <p>Methods</p> <p>We treated isolated mouse tibialis anterior (TA) and medial gastrocnemius (MG) muscles in tissue bath with the selective dopamine 1 receptor and dopamine 5 receptor agonist SKF 81297 to determine if activation of skeletal muscle dopamine 1 and dopamine 5 receptors will increase cAMP. We dosed wild-type mice, dopamine 1 receptor knockout mice and dopamine 5 receptor knockout mice undergoing casting-induced disuse atrophy with SKF 81297 to determine if activation of the dopamine 1 and dopamine 5 receptors results in hypertrophy of non-atrophying skeletal muscle and preservation of atrophying skeletal muscle mass and force production.</p> <p>Results</p> <p>In tissue bath, isolated mouse TA and MG muscles responded to SKF 81297 treatment with increased cAMP levels. Treating wild-type mice with SKF 81297 reduced casting-induced TA and MG muscle mass loss in addition to increasing the mass of non-atrophying TA and MG muscles. In dopamine 1 receptor knockout mice, extensor digitorum longus (EDL) and soleus muscle mass and force was not preserved during casting with SKF 81297 treatment, in contrast to significant preservation of casted wild-type mouse EDL and soleus mass and EDL force with SKF 81297 treatment. Dosing dopamine 5 receptor knockout mice with SKF 81297 did not significantly preserve EDL and soleus muscle mass and force although wild-type mouse EDL mass and force was significantly preserved SKF 81297 treatment.</p> <p>Conclusions</p> <p>These data demonstrate for the first time that treatment with a dopamine 1/5 receptor agonist results in (1) significant preservation of EDL, TA, MG and soleus muscle mass and EDL muscle force production during periods of atrophy and (2) hypertrophy of TA and MG muscle. These effects appear to be mainly mediated by both the dopamine 1 and dopamine 5 receptors.</p
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Factors affecting the motivation of healthcare professionals providing care to Emiratis with type 2 diabetes
OBJECTIVE: We aimed to identify facilitators of and barriers to healthcare professionals' motivation in a diabetes centre in the United Arab Emirates (UAE).
DESIGN: A qualitative research approach was employed using semistructured interviews to assess perception of and attitudes regarding healthcare professionals' motivation in providing good quality diabetes care.
SETTING: A diabetes centre located in Abu-Dhabi, UAE.
PARTICIPANTS: Healthcare professionals including specialist physicians, dieticians, podiatrists, health educators and nurses were recruited through purposive sampling.
MAIN OUTCOME MEASURES: After data collection, the audiotaped interviews were transcribed verbatim and subjected to content analysis.
RESULTS: Nine semistructured interviews were conducted with healthcare professionals of various professional backgrounds. Important facilitators and barriers related to patient, professional, organization and cultural factors were identified. Barriers that related to heavy workload, disjointed care, lack of patient compliance and awareness, and cultural beliefs and attitudes about diabetes were common. Key facilitators included the patient's role in achieving therapeutic outcomes as well as compliance, cooperation and communication.
CONCLUSION: This qualitative study provides some unique insights about factors affecting healthcare professionals' motivation in providing good quality care. To improve the motivation of healthcare professionals in the management of diabetes and therefore the quality of diabetes care, several steps are needed. Importantly, the role of primary care should be reinforced and strengthened regarding the management of type 2 diabetes mellitus, privacy of the consultation time should be highly protected and regulated, and awareness of the Emirate culture and its impact on health should be disseminated to the healthcare professionals providing care to Emirates with diabetes. Also, greater emphasis should be placed on educating Emiratis with diabetes on, and involving them in, the management of their condition
Role of Serine Racemase in Behavioral Sensitization in Mice after Repeated Administration of Methamphetamine
BACKGROUND: The N-methyl-D-aspartate (NMDA) receptors play a role in behavioral abnormalities observed after administration of the psychostimulant, methamphetamine (METH). Serine racemase (SRR) is an enzyme which synthesizes D-serine, an endogenous co-agonist of NMDA receptors. Using Srr knock-out (KO) mice, we investigated the role of SRR on METH-induced behavioral abnormalities in mice. METHODOLOGY/PRINCIPAL FINDINGS: Evaluations of behavior in acute hyperlocomotion, behavioral sensitization, and conditioned place preference (CPP) were performed. The role of SRR on the release of dopamine (DA) in the nucleus accumbens after administration of METH was examined using in vivo microdialysis technique. Additionally, phosphorylation levels of ERK1/2 proteins in the striatum, frontal cortex and hippocampus were examined using Western blot analysis. Acute hyperlocomotion after a single administration of METH (3 mg/kg) was comparable between wild-type (WT) and Srr-KO mice. However, repeated administration of METH (3 mg/kg/day, once daily for 5 days) resulted in behavioral sensitization in WT, but not Srr-KO mice. Pretreatment with D-serine (900 mg/kg, 30 min prior to each METH treatment) did not affect the development of behavioral sensitization after repeated METH administration. In the CPP paradigm, METH-induced rewarding effects were demonstrable in both WT and Srr-KO mice. In vivo microdialysis study showed that METH (1 mg/kg)-induced DA release in the nucleus accumbens of Srr-KO mice previously treated with METH was significantly lower than that of the WT mice previously treated with METH. Interestingly, a single administration of METH (3 mg/kg) significantly increased the phosphorylation status of ERK1/2 in the striatum of WT, but not Srr-KO mice. CONCLUSIONS/SIGNIFICANCE: These findings suggest first, that SRR plays a role in the development of behavioral sensitization in mice after repeated administration of METH, and second that phosphorylation of ERK1/2 by METH may contribute to the development of this sensitization as seen in WT but not Srr-KO mice
The complex X-ray spectrum of NGC 4507
XMM-Newton and Chandra/HETG spectra of the Compton-thin (NH 4x10^{23}
cm^{-2}) Seyfert 2 galaxy, NGC 4507, are analyzed and discussed. The main
results are: a) the soft X-ray emission is rich in emission lines; an (at
least) two--zone photoionization region is required to explain the large range
of ionization states. b) The 6.4 keV iron line is likely emitted from
Compton-thick matter, implying the presence of two circumnuclear cold regions,
one Compton-thick (the emitter), one Compton-thin (the cold absorber). c)
Evidence of an Fe xxv absorption line is found in the Chandra/HETG spectrum.
The column density of the ionized absorber is estimated to be a few x10^{22}
cm^{-2}.Comment: accepted for publication in A&
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