914 research outputs found
Effect of active immunization against growth hormone releasing factor on concentrations of somatotropin and insulin-like growth factor I in lactating beef cows
Two experiments were conducted to determine the effects of immunoneutralization of growth hormone-releasing factor [GRF(1–29)-NH2] on concentrations of somatotropin (ST) and insulin-like growth factor I (IGF-I) in lactating beef cows. In Experiment 1, multiparous Hereford cows were immunized against 2 mg GRF(1–29)-(Gly)4-Cys-NH2 conjugated to human serum albumin (GRFi, n=3) or 2 mg human serum albumin (HSAi, n=3) at 52 ± 1 d prior to parturition. Boosters (1 mg) were administered on days 12, 40 and 114 postpartum (pp). Serum samples were collected at 15-min intervals for 5 hr on days 18, 46 and 120 pp, followed by administration (IV) of an opioid agonist (FK33-824; 10 μg/kg) and an antagonist (naloxone; .5 mg/kg) at hours 5 and 7, respectively. A GRF-analog ([desamino-Tyr1, D-Ala2, Ala15] GRF (1–29)-NH2; 3.5 μg/kg) and arginine (.5 g/kg) were administered at hour 10 on days 47 and 121, respectively. Percentage binding of [125I]GRF (1:100 dilution of serum) 28 d after primary immunization was greater in GRFi (14.3 ± 4.9) than in HSAi (.7 ± .3) cows. Binding increased to 29.3 ± 6.5% after first booster in GRFi cows. Episodic release of ST was abolished by immunization against GRF; concentration and frequency of release of ST were lower (P125I]GRF, absence of pulsatile release of ST, low concentrations of ST and IGF-I and failure of ST to increase after IV opioid agonist or arginine
Evaluating the sensitivity of hybridization-based epigenotyping using a methyl binding domain protein
Hypermethylation of CpG islands in gene promoter regions has been shown to be a predictive biomarker for certain diseases. Most current methods for methylation profiling are not well-suited for clinical analysis. Here, we report the development of an inexpensive device and an epigenotyping assay with a format conducive to multiplexed analysis.David H. Koch Institute for Integrative Cancer Research at MIT (First-year Graduate Fellowship)National Science Foundation (U.S.). Graduate Research FellowshipBurroughs Wellcome Fund (Career Award at the Scientific Interface)National Institute of Environmental Health Sciences (Grant P30-ES002109)Massachusetts Institute of Technology. James H. Ferry Fund for Innovation in Research Educatio
Secondary syringe exchange as a model for HIV prevention programs in the Russian Federation
Effective prevention of syringe-borne transmission of HIV and the hepatitis viruses can be undermined if contact between injection drug users and the staff of prevention programs is impeded by police harassment, limited program resources, and the absence of an open "drug scene." All these are commonplace in the Russian Federation. In response, "Project Renewal," the harm reduction program of the AIDS Prevention and Control Center of the Tatarstan Ministry of Health in Kazan, has created a hybrid syringe exchange program that as its primary focus recruited and trained volunteers to provide secondary syringe exchange. To compensate for operational barriers, the program staff identified private venues and trained responsible individuals to work through their own and related networks of injectors to provide clean syringes, other harm reduction supplies, and educational materials, while facilitating the collection and removal of used and potentially contaminated syringes. Program staff developed a detailed set of tracking instruments to monitor, on a daily and weekly basis, the locations and types of contacts and the dissemination of trainings and materials to ensure that the secondary distribution network reaches its target audience. Data show that these secondary exchange sites have proven more productive than the primary mobile and fixed-site syringe exchanges in Kazan. Beginning in 2001, Project Renewal has trained other harm reduction programs in the Russian Federation to use this model of reaching injectors, identifying and training volunteers, and monitoring results of secondary syringe exchange. Copyright © 2006 Taylor & Francis Group, LLC
Resistance of Dictyostelium discoideum membranes to saponin permeabilization
<p>Abstract</p> <p>Background</p> <p>Saponin is a mild detergent commonly used to permeabilize cells prior to immunofluorescence labeling of intracellular proteins. It has previously been used to that effect in <it>Dictyostelium discoideum </it>amoebae.</p> <p>Findings</p> <p>We show that saponin, contrary to Triton X-100 or alcohol, permeabilizes at best incompletely membranes of <it>Dictyostelium</it>. In cells exposed to osmotic stress, almost complete resistance to saponin permeabilization was observed.</p> <p>Conclusions</p> <p>Saponin should be used with special care to permeabilize <it>Dictyostelium </it>membranes. This unsusual property is presumably linked to the specific sterol composition of <it>Dictyostelium </it>membranes. It may also represent an adaptation of <it>Dictyostelium </it>to harsh conditions or to natural compounds encountered in its natural environment.</p
Imaging of alert patients after non-self-inflicted strangulation: MRI is superior to CT.
OBJECTIVE
To assess the accuracy of CT and MRI reports of alert patients presenting after non-self-inflicted strangulation (NSIS) and evaluate the appropriateness of these imaging modalities in NSIS.
MATERIAL AND METHODS
The study was a retrospective analysis of patient characteristics and strangulation details, with a comparison of original radiology reports (ORR) to expert read-outs (EXR) of CT and MRI studies of all NSIS cases seen from 2008 to 2020 at a single centre.
RESULTS
The study included 116 patients (71% women, p < .001, χ2), with an average age of 33.8 years, mostly presenting after manual strangulation (97%). Most had experienced intimate partner violence (74% of women, p < .001, χ2) or assault by unknown offender (88% of men, p < 0.002 χ2). Overall, 132 imaging studies (67 CT, 51% and 65 MRI, 49%) were reviewed. Potentially dangerous injuries were present in 7%, minor injuries in 22%, and no injuries in 71% of patients. Sensitivity and specificity of ORR were 78% and 97% for MRI and 30% and 98% for CT. Discrepancies between ORR and EXR occurred in 18% of all patients, or 62% of injured patients, with a substantial number of unreported injuries on CT.
CONCLUSIONS
The results indicate that MRI is more appropriate than CT for alert patients presenting after non-self-inflicted strangulation and underline the need for radiologists with specialist knowledge to report these cases in order to add value to both patient care and potential future medico-legal investigations.
CLINICAL RELEVANCE STATEMENT
MRI should be preferred over CT for the investigation of strangulation related injuries in alert patients because MRI has a higher accuracy than CT and does not expose this usually young patient population to ionizing radiation.
KEY POINTS
• Patients presenting after strangulation are often young women with a history of intimate partner violence while men typically present after assault by an unknown offender. • Expert read-outs of CT and MRI revealed potentially dangerous injuries in one of 14 patients. • MRI has a significantly higher sensitivity than CT and appears to be more appropriate for the diagnostic workup of alert patients after strangulation
Profitable failure: antidepressant drugs and the triumph of flawed experiments
Drawing on an analysis of Irving Kirsch and colleagues? controversial 2008 article in PLoS [Public Library of Science] Medicine on the efficacy of SSRI antidepressant drugs such as Prozac, I examine flaws within the methodologies of randomized controlled trials (RCTs) that have made it difficult for regulators, clinicians and patients to determine the therapeutic value of this class of drug. I then argue, drawing analogies to work by Pierre Bourdieu and Michael Power, that it is the very limitations of RCTs ? their inadequacies in producing reliable evidence of clinical effects ? that help to strengthen assumptions of their superiority as methodological tools. Finally, I suggest that the case of RCTs helps to explore the question of why failure is often useful in consolidating the authority of those who have presided over that failure, and why systems widely recognized to be ineffective tend to assume greater authority at the very moment when people speak of their malfunction
Neural correlates of enhanced visual short-term memory for angry faces: An fMRI study
Copyright: © 2008 Jackson et al.Background: Fluid and effective social communication requires that both face identity and emotional expression information are encoded and maintained in visual short-term memory (VSTM) to enable a coherent, ongoing picture of the world and its players. This appears to be of particular evolutionary importance when confronted with potentially threatening displays of emotion - previous research has shown better VSTM for angry versus happy or neutral face identities.Methodology/Principal Findings: Using functional magnetic resonance imaging, here we investigated the neural correlates of this angry face benefit in VSTM. Participants were shown between one and four to-be-remembered angry, happy, or neutral faces, and after a short retention delay they stated whether a single probe face had been present or not in the previous display. All faces in any one display expressed the same emotion, and the task required memory for face identity. We find enhanced VSTM for angry face identities and describe the right hemisphere brain network underpinning this effect, which involves the globus pallidus, superior temporal sulcus, and frontal lobe. Increased activity in the globus pallidus was significantly correlated with the angry benefit in VSTM. Areas modulated by emotion were distinct from those modulated by memory load.Conclusions/Significance: Our results provide evidence for a key role of the basal ganglia as an interface between emotion and cognition, supported by a frontal, temporal, and occipital network.The authors were supported by a Wellcome Trust grant (grant number 077185/Z/05/Z) and by BBSRC (UK) grant BBS/B/16178
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