2,971 research outputs found
Pathways to treatment retention for individuals legally coerced to substance use treatment: The interaction of hope and treatment motivation
Although several states have adopted policies diverting individuals convicted of non-violent drug offenses to substance use treatment, in lieu of incarceration or as a condition of probation, previous research has produced inconsistent findings on the effectiveness of such programs when comparing outcomes for legally coerced individuals to more voluntary entrants. Less studied in these populations is within group variation in treatment expectations and motivation influences, which have been shown to affect retention as well. As motivation has traditionally been viewed as contributing to treatment retention and higher levels of hope (the perception that goals can be met) are viewed as an asset in treatment, the role of these factors in predicting better retention between legally coerced and more voluntary clients were examined in a sample of 289 treatment admissions in California. Results found that motivation mediates the relationship between hope and retention for participants in general. Although the differences in mediation between the legally coerced and the non-legally coerced were not significant, when examining the groups separately, there was a significant mediation of the relationship between hope and retention by motivation only for those individuals who were not legally coerced into treatment (p\u3c.05). The findings imply that while being legally coerced may lead to different pathways to treatment retention, for individuals who were not legally coerced, higher levels of hope may play an important role in determining treatment retentio
Pathways to treatment retention for individuals legally coerced to substance use treatment: The interaction of hope and treatment motivation
Although several states have adopted policies diverting individuals convicted of non-violent drug offenses to substance use treatment, in lieu of incarceration or as a condition of probation, previous research has produced inconsistent findings on the effectiveness of such programs when comparing outcomes for legally coerced individuals to more voluntary entrants. Less studied in these populations is within group variation in treatment expectations and motivation influences, which have been shown to affect retention as well. As motivation has traditionally been viewed as contributing to treatment retention and higher levels of hope (the perception that goals can be met) are viewed as an asset in treatment, the role of these factors in predicting better retention between legally coerced and more voluntary clients were examined in a sample of 289 treatment admissions in California. Results found that motivation mediates the relationship between hope and retention for participants in general. Although the differences in mediation between the legally coerced and the non-legally coerced were not significant, when examining the groups separately, there was a significant mediation of the relationship between hope and retention by motivation only for those individuals who were not legally coerced into treatment (p\u3c.05). The findings imply that while being legally coerced may lead to different pathways to treatment retention, for individuals who were not legally coerced, higher levels of hope may play an important role in determining treatment retentio
Opioids depress cortical centers responsible for the volitional control of respiration
Respiratory depression limits provision of safe opioid analgesia and is the main cause of death in drug addicts. Although opioids are known to inhibit brainstem respiratory activity, their effects on cortical areas that mediate respiration are less well understood. Here, functional magnetic resonance imaging was used to examine how brainstem and cortical activity related to a short breath hold is modulated by the opioid remifentanil. We hypothesized that remifentanil would differentially depress brain areas that mediate sensory-affective components of respiration over those that mediate volitional motor control. Quantitative measures of cerebral blood flow were used to control for hypercapnia-induced changes in blood oxygen level-dependent (BOLD) signal. Awareness of respiration, reflected by an urge-to-breathe score, was profoundly reduced with remifentanil. Urge to breathe was associated with activity in the bilateral insula, frontal operculum, and secondary somatosensory cortex. Localized remifentanil-induced decreases in breath hold-related activity were observed in the left anterior insula and operculum. We also observed remifentanil-induced decreases in the BOLD response to breath holding in the left dorsolateral prefrontal cortex, anterior cingulate, the cerebellum, and periaqueductal gray, brain areas that mediate task performance. Activity in areas mediating motor control (putamen, motor cortex) and sensory-motor integration (supramarginal gyrus) were unaffected by remifentanil. Breath hold-related activity was observed in the medulla. These findings highlight the importance of higher cortical centers in providing contextual awareness of respiration that leads to appropriate modulation of respiratory control. Opioids have profound effects on the cortical centers that control breathing, which potentiates their actions in the brainstem
Multiwaveband analysis of brightest GRB070125
We present a comprehensive multiwavelength analysis of the bright, long duration gamma-ray burst GRB 070125, comprised of observations in gamma-ray, X-ray, optical, millimeter and centimeter wavebands. Radio light curves show rapid flux variations, which are interpreted as due to interstellar scintillation, and are used to derive an upper limit of 2.4×10^17 cm on the radius of the fireball. Radio light curves and spectra suggest that the afterglow shock wave is moving in a dense medium. Our broadband modeling favors a constant density profile for the circumburst medium over a wind-like profile (R^−2). GRB 070125 is a burst with high radiative efficiency (>60%)
Superoxide Signaling in Perivascular Adipose Tissue Promotes Age-Related Artery Stiffness
We tested the hypothesis that superoxide signaling within aortic perivascular adipose tissue (PVAT) contributes to large elastic artery stiffening in old mice. Young (4-6 months), old (26-28 months), and old treated with 4-Hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPOL), a superoxide scavenger (1 mm in drinking water for 3 weeks), male C57BL6/N mice were studied. Compared with young, old had greater large artery stiffness assessed by aortic pulse wave velocity (aPWV, 436 ± 9 vs. 344 ± 5 cm s(-1)) and intrinsic mechanical testing (3821 ± 427 vs. 1925 ± 271 kPa) (both P \u3c 0.05). TEMPOL treatment in old reversed both measures of arterial stiffness. Aortic PVAT superoxide production was greater in old (P \u3c 0.05 vs. Y), which was normalized with TEMPOL. Compared with young, old controls had greater pro-inflammatory proteins in PVAT-conditioned media (P \u3c 0.05). Young recipient mice transplanted with PVAT from old compared with young donors for 8 weeks had greater aPWV (409 ± 7 vs. 342 ± 8 cm s(-1)) and intrinsic mechanical properties (3197 ± 647 vs. 1889 ± 520 kPa) (both P \u3c 0.05), which was abolished with TEMPOL supplementation in old donors. Tissue-cultured aortic segments from old in the presence of PVAT had greater mechanical stiffening compared with old cultured in the absence of PVAT and old with PVAT and TEMPOL (both, P \u3c 0.05). In addition, PVAT-derived superoxide was associated with arterial wall hypertrophy and greater adventitial collagen I expression with aging that was attenuated by TEMPOL. Aging or TEMPOL treatment did not affect blood pressure. Our findings provide evidence for greater age-related superoxide production and pro-inflammatory proteins in PVAT, and directly link superoxide signaling in PVAT to large elastic artery stiffness
Diatom control of the autotrophic community and particle export in the eastern Bering Sea during the recent cold years (2008–2010)
The southeastern Bering Sea has exhibited shifts in climate since the start of the 21st century. The regional climate shifts are manifested in the duration and areal extent of seasonal sea-ice coverage. During a recent cold period (2008–2010) with extensive spring sea-ice cover over the southeastern shelf of the Bering Sea, a total of 77 water column and 24 sediment trap profiles were collected over the shelf and shelf break and analyzed for autotrophic pigment concentrations and elemental (carbon, nitrogen, phosphorus, and silicon) concentrations in suspended and exported particulate material. These results are used to establish the seasonal succession of the autotrophic community and the control that both phytoplankton and zooplankton exert on export production. In spring (April to mid-June), total chlorophyll a (TChl a) concentrations were generally low (i.e., \u3c 1 μg L–1); however, localized phytoplankton blooms near the marginal ice zone (MIZ) lead to elevated spring average TChl a concentrations (i.e., \u3e5 μg L–1). In summer (mid-June to late July), photic zone chlorophyll a concentrations were typically \u3c1 μg L–1 over the shelf and at the shelf break. Diatoms represented the greatest contribution to TChl a (regional averages of 71%–96% in spring and 25%–75% in summer) and autotrophic biomass in spring and summer. This algal class also represented 50%–99% of TChl a associated with particles sinking from the photic zone. The relatively high proportion of phaeophorbide a in sediment trap material indicates that sinking of zooplankton fecal pellets facilitate the export of particles through the water column. Further, zooplankton grazing may be an important process that returns regenerated nutrients to the water column based on the elemental composition of suspended and sinking particles. In colder than average years, the emergence of diatom blooms in the spring MIZ supports the production of abundant large zooplankton, which are a primary food source for juvenile pelagic fishes of economically important species. Therefore, processes in colder than average years may be essential for the transfer of particulate organic carbon from the surface waters and the success of the economically important pelagic fisheries
D2/D3 dopamine receptor binding with [F-18]fallypride correlates of executive function in medication-naïve patients with schizophrenia
Converging evidence indicates that the prefrontal cortex is critically involved in executive control and that executive dysfunction is implicated in schizophrenia. Reduced dopamine D2/D3 receptor binding potential has been reported in schizophrenia, and the correlations with neuropsychological test scores have been positive and negative for different tasks. The aim of this study was to examine the relation between dopamine D2/D3 receptor levels with frontal and temporal neurocognitive performance in schizophrenia. Resting-state 18F-fallypride positron emission tomography was performed on 20 medication-naïve and 5 previously medicated for brief earlier periods patients with schizophrenia and 19 age- and sex-matched healthy volunteers. Striatal and extra-striatal dopamine D2/D3 receptor levels were quantified as binding potential using fallypride imaging. Magnetic resonance images in standard Talairach position and segmented into gray and white matter were co-registered to the fallypride images, and the AFNI stereotaxic atlas was applied. Two neuropsychological tasks known to activate frontal and temporal lobe function were chosen, specifically the Wisconsin Card Sorting Test (WCST) and the California Verbal Learning Test (CVLT). Images of the correlation coefficient between fallypride binding and WCST and CVLT performance showed a negative correlation in contrast to positive correlations in healthy volunteers. The results of this study demonstrate that lower fallypride binding potential in patients with schizophrenia may be associated with better performance. Our findings are consistent with previous studies that failed to find cognitive improvements with typical dopamine-blocking medications
Spectropolarimetry of SN 2011dh in M51: geometric insights on a Type IIb supernova progenitor and explosion
We present seven epochs of spectropolarimetry of the Type IIb supernova (SN)
2011dh in M51, spanning 86 days of its evolution. The first epoch was obtained
9 days after the explosion, when the photosphere was still in the depleted
hydrogen layer of the stripped-envelope progenitor. Continuum polarization is
securely detected at the level of P~0.5% through day 14 and appears to diminish
by day 30, which is different from the prevailing trends suggested by studies
of other core-collapse SNe. Time-variable modulations in P and position angle
are detected across P-Cygni line features. H-alpha and HeI polarization peak
after 30 days and exhibit position angles roughly aligned with the earlier
continuum, while OI and CaII appear to be geometrically distinct. We discuss
several possibilities to explain the evolution of the continuum and line
polarization, including the potential effects of a tidally deformed progenitor
star, aspherical radioactive heating by fast-rising plumes of Ni-56 from the
core, oblique shock breakout, or scattering by circumstellar material. While
these possibilities are plausible and guided by theoretical expectations, they
are not unique solutions to the data. The construction of more detailed
hydrodynamic and radiative-transfer models that incorporate complex aspherical
geometries will be required to further elucidate the nature of the polarized
radiation from SN 2011dh and other Type IIb supernovae.Comment: Post-proof edit. Accepted to MNRAS 2015 Aug 1
Contrasting Effects of Lower Body Positive Pressure on Upper Airways Resistance and Partial Pressure of Carbon Dioxide in Men With Heart Failure and Obstructive or Central Sleep Apnea
ObjectivesThis study sought to test the effects of rostral fluid displacement from the legs on transpharyngeal resistance (Rph), minute volume of ventilation (Vmin), and partial pressure of carbon dioxide (PCO2) in men with heart failure (HF) and either obstructive (OSA) or central sleep apnea (CSA).BackgroundOvernight rostral fluid shift relates to severity of OSA and CSA in men with HF. Rostral fluid displacement may facilitate OSA if it shifts into the neck and increases Rph, because pharyngeal obstruction causes OSA. Rostral fluid displacement may also facilitate CSA if it shifts into the lungs and induces reflex augmentation of ventilation and reduces PCO2, because a decrease in PCO2 below the apnea threshold causes CSA.MethodsMen with HF were divided into those with mainly OSA (obstructive-dominant, n = 18) and those with mainly CSA (central-dominant, n = 10). While patients were supine, antishock trousers were deflated (control) or inflated for 15 min (lower body positive pressure [LBPP]) in random order.ResultsLBPP reduced leg fluid volume and increased neck circumference in both obstructive- and central-dominant groups. However, in contrast to the obstructive-dominant group in whom LBPP induced an increase in Rph, a decrease in Vmin, and an increase in PCO2, in the central-dominant group, LBPP induced a reduction in Rph, an increase in Vmin, and a reduction in PCO2.ConclusionsThese findings suggest mechanisms by which rostral fluid shift contributes to the pathogenesis of OSA and CSA in men with HF. Rostral fluid shift could facilitate OSA if it induces pharyngeal obstruction, but could also facilitate CSA if it augments ventilation and lowers PCO2
Promiscuous actions of small molecule inhibitors of the protein kinase D-class IIa HDAC axis in striated muscle
AbstractPKD-mediated phosphorylation of class IIa HDACs frees the MEF2 transcription factor to activate genes that govern muscle differentiation and growth. Studies of the regulation and function of this signaling axis have involved MC1568 and Gö-6976, which are small molecule inhibitors of class IIa HDAC and PKD catalytic activity, respectively. We describe unanticipated effects of these compounds. MC1568 failed to inhibit class IIa HDAC catalytic activity in vitro, and exerted divergent effects on skeletal muscle differentiation compared to a bona fide inhibitor of these HDACs. In cardiomyocytes, Gö-6976 triggered calcium signaling and activated stress-inducible kinases. Based on these findings, caution is warranted when employing MC1568 and Gö-6976 as pharmacological tool compounds to assess functions of class IIa HDACs and PKD
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