231 research outputs found
Noradrenergic Pharmacotherapy, Intracerebral Infusion and Adrenal Transplantation Promote Functional Recovery After Cortical Damage
The research described in this review briefly
summarizes evidence that short term
pharmacological enhancement of noradrenergic
(NA) synaptic activity, combined with symptom
relevant experience (SRE), promotes functional
recovery of some symptoms of cortical damage
in rat, cat and human beings even when
treatment is initiated from days to weeks after
injury. A summary is provided of the numerous
drugs tested in rodent cortical injury models
which have been proven useful for predicting
beneficial or harmful effects on behavioral
outcome in human stroke. The pattern of drug
effects indicates a central role for NA in
functional recovery. Additionally, studies of the
effects of direct intraventricular infusion of
monoamine neurotransmitters are reviewed and
further support the hypothesized role of NA in
recovery from some symptoms of cortical injury.
The site of NA/SRE interaction to promote
recovery from hemiplegia apparently involves
the cerebellar hemisphere contralateral to the
cortical injury. Microinfusions of NA into the
contra- but not ipsilaterai cerebellar hemisphere
dramatically enhance recovery. Furthermore,
like its systemic action, microinfusion of the α1-
NA receptor antagonist, phenoxybenzamine,
reinstates hemiplegia. A “permanent” symptom
of motor cortex injury in the cat is the complete
loss of tactile placing contralateral to the injury
which does not spontaneously recover for as
long as seven years after ablation. This posturai
reflex is temporarily restored for 8-12 hours
following amphetamine administration.
However, this permanently lost reflex can be
enduringly restored by transplanting catecholamine secreting adrenal tissue into the
wound cavity. The experiment is reviewed in
detail and involves chromaffin cell autografts
into the frontal cortex ablation wound cavity
producing a restoration of tactile placing for the
7-10 month duration of the study. This enduring
restoration of tactile placing is considered a
result of the release of catecholamines into the
CNS from the grafted chromaffin cells found, by
histochemical methods, surviving 7-10 months
after transplant. Lastly, we attribute these
delayed treatment effects to an attenuation of a
diaschisis, or remote functional depression, in
morphologically intact areas anatomically
connected to the area of injury. The widespread
reduction of glycolytic and oxidative
metabolism, produced by focal cortical injury, is
normalized by the same treatment which
alleviates symptoms and is worsened by drugs
which exacerbate deficits. These data support
the hypothesis that providing SRE during a
period of enhanced NA synaptic activity
produces an enduring functional recovery after
cortical injury by attenuating remote functional
depression. This treatment for enhancing
recovery is especially attractive since it is
effective even when begun weeks after cortical
damage
Medical student use of communication elements and association with patient satisfaction: a prospective observational pilot study
BACKGROUND:
Effective communication with patients impacts clinical outcome and patient satisfaction. We measure the rate at which medical students use six targeted communication elements with patients and association of element use with patient satisfaction.
METHODS:
Participants included fourth year medical students enrolled in an emergency medicine clerkship. A trained observer measured use of six communication elements: acknowledging the patient by name, introducing themselves by name, identifying their role, explaining the care plan, explaining that multiple providers would see the patient, and providing an estimated duration of time in the emergency department. The observer then conducted a survey of patient satisfaction with the medical student encounter.
RESULTS:
A total of 246 encounters were documented among forty medical student participants. For the six communication elements evaluated, in 61% of encounters medical students acknowledged the patient, in 91% they introduced themselves, in 58 % they identified their role as a student, in 64% they explained the care plan, in 80% they explained that another provider would see the patient, and in only 6% they provided an estimated duration of care. Only 1 encounter (0.4%) contained all six elements. Patients' likelihood to refer a loved one to that ED was increased when students acknowledged the patient and described that other providers would be involved in patient care (P = 0.016 and 0.015 respectively, Chi Square). Likewise, patients' likelihood to return to the ED was increased when students described their role in patient care (P = 0.035, Chi Square).
CONCLUSIONS:
This pilot study demonstrates that medical students infrequently use all targeted communication elements. When they did use certain elements, patient satisfaction increased. These data imply potential benefit to additional training for students in patient communication
Inhaled nitric oxide to treat intermediate risk pulmonary embolism: A multicenter randomized controlled trial
Objective
To test the hypothesis that adjunctive inhaled NO would improve RV function and viability in acute PE.
Methods
This was a randomized, placebo-controlled, double blind trial conducted at four academic hospitals. Eligible patients had acute PE without systemic arterial hypotension but had RV dysfunction and a treatment plan of standard anticoagulation. Subjects received either oxygen plus 50 parts per million nitrogen (placebo) or oxygen plus 50 ppm NO for 24 h. The primary composite endpoint required a normal RV on echocardiography and a plasma troponin T concentration <14 pg/mL. The secondary endpoint required a blood brain natriuretic peptide concentration <90 pg/mL and a Borg dyspnea score ≤ 2. The sample size of N = 76 tested if 30% more patients treated with NO would achieve the primary endpoint with 80% power and alpha = 5%.
Results
We randomized 78 patients and after two withdrawals, 38 were treated per protocol in each group. Patients were well matched for baseline conditions. At 24 h, 5/38 (13%) of patients treated with placebo and 9/38 (24%) of patients treated with NO reached the primary endpoint (P = 0.375). The secondary endpoint was reached in 34% with placebo and 13% of the NO (P = 0.11). In a pre-planned post-hoc analysis, we examined how many patients with RV hypokinesis or dilation at enrollment resolved these abnormalities; 29% more patients treated with NO resolved both abnormalities at 24 h (P = 0.010, Cochrane's Q test).
Conclusions
In patients with severe submassive PE, inhaled nitric oxide failed to increase the proportion of patients with a normal troponin and echocardiogram but increased the probability of eliminating RV hypokinesis and dilation on echocardiography
Environmental enrichment improves traumatic brain injury-induced behavioral phenotype and associated neurodegenerative process
Producción CientíficaTraumatic brain injury (TBI) causes persistent cognitive impairment and neurodegeneration. Environmental enrichment (EE) refers to a housing condition that promotes sensory and social stimulation and improves cognition and motor performance but the underlying mechanisms responsible for such beneficial effects are not well defined. In this study, anesthetized adult rats received either a moderate-to-severe controlled cortical impact (CCI) or sham surgery and then were housed in either EE or standard conditions. The results showed a significant increase in protein nitration and oxidation of lipids, impaired cognition and motor performance, and augmented N-methyl-d-aspartate receptor subtype-1 (NMDAR1) levels. However, EE initiated 24 h after CCI resulted in reduced oxidative insult and microglial activation and significant improvement in beam-balance/walk performance and both spatial learning and memory. We hypothesize that following TBI there is an upstream activation of NMDAR that promotes oxidative insult and an inflammatory response, thereby resulting in impaired behavioral functioning but EE may exert a neuroprotective effect via sustained downregulation of NMDAR1
Odorant-Binding Proteins of the Malaria Mosquito Anopheles funestus sensu stricto
is one of the major malaria vector species in sub-Saharan Africa. Olfaction is essential in guiding mosquito behaviors. Odorant-binding proteins (OBPs) are highly expressed in insect olfactory tissues and involved in the first step of odorant reception. An improved understanding of the function of malaria mosquito OBPs may contribute to identifying new attractants/repellents and assist in the development of more efficient and environmentally friendly mosquito controlling strategies. female antennae. To compare the absolute efficiency/potency of these chemicals, corrections were made for differences in volatility by determining the exact amount in a stimulus puff. Fourteen AfunOBP genes were cloned and their expression patterns were analyzed. AfunOBP1, 3, 7, 20 and 66 showed olfactory tissue specificity by reverse transcriptase PCR (RT-PCR). Quantitative real-time PCR (qRT-PCR) analysis showed that among olfactory-specific OBPs, AfunOBP1 and 3 are the most enriched OBPs in female antennae. Binding assay experiments showed that at pH 7, AfunOBP1 significantly binds to 2-undecanone, nonyl acetate, octyl acetate and 1-octen-3-ol but AfunOBP3, which shares 68% identify with AfunOBP1 at amino acid level, showed nearly no binding activity to the selected 12 EAG-active odorant compounds. olfactory system, and help developing new mosquito control strategies to reduce malaria transmission
Refining trait resilience: identifying engineering, ecological, and adaptive facets from extant measures of resilience
The current paper presents a new measure of trait resilience derived from three common
mechanisms identified in ecological theory: Engineering, Ecological and Adaptive (EEA)
resilience. Exploratory and confirmatory factor analyses of five existing resilience scales
suggest that the three trait resilience facets emerge, and can be reduced to a 12-item scale.
The conceptualization and value of EEA resilience within the wider trait and well-being psychology
is illustrated in terms of differing relationships with adaptive expressions of the traits
of the five-factor personality model and the contribution to well-being after controlling for
personality and coping, or over time. The current findings suggest that EEA resilience is a
useful and parsimonious model and measure of trait resilience that can readily be placed
within wider trait psychology and that is found to contribute to individual well-bein
Analysis of Polymorphisms and Haplotype Structure of the Human Thymidylate Synthase Genetic Region: A Tool for Pharmacogenetic Studies
5-fluorouracil (5FU), a widely used chemotherapeutic drug, inhibits the DNA replicative enzyme, thymidylate synthase (Tyms). Prior studies implicated a VNTR (variable numbers of tandem repeats) polymorphism in the 5′-untranslated region (5′-UTR) of the TYMS gene as a determinant of Tyms expression in tumors and normal tissues and proposed that these VNTR genotypes could help decide fluoropyrimidine dosing. Clinical associations between 5FU-related toxicity and the TYMS VNTR were reported, however, results were inconsistent, suggesting that additional genetic variation in the TYMS gene might influence Tyms expression. We thus conducted a detailed genetic analysis of this region, defining new polymorphisms in this gene including mononucleotide (poly A:T) repeats and novel single nucleotide polymorphisms (SNPs) flanking the VNTR in the TYMS genetic region. Our haplotype analysis of this region used data from both established and novel genetic variants and found nine SNP haplotypes accounting for more than 90% of the studied population. We observed non-exclusive relationships between the VNTR and adjacent SNP haplotypes, such that each type of VNTR commonly occurred on several haplotype backgrounds. Our results confirmed the expectation that the VNTR alleles exhibit homoplasy and lack the common ancestry required for a reliable marker of a linked adjacent locus that might govern toxicity. We propose that it may be necessary in a clinical trial to assay multiple types of genetic polymorphisms in the TYMS region to meaningfully model linkage of genetic markers to 5FU-related toxicity. The presence of multiple long (up to 26 nt), polymorphic monothymidine repeats in the promoter region of the sole human thymidylate synthetic enzyme is intriguing
Use of Motor Abundance in Young and Older Adults during Dual-Task Treadmill Walking
Contains fulltext :
110120.pdf (publisher's version ) (Open Access)Motor abundance allows individuals to perform any task reliably while being variable in movement's particulars. The study investigated age-related differences in this feature when young adults (YA) and older adults (OA) performed challenging tasks, namely treadmill walking alone and while performing a cognitive task. A goal function for treadmill walking was first defined, i.e., maintain constant speed at each step, which led to a goal equivalent manifold (GEM) containing all combinations of step time and step length that equally satisfied the function. Given the GEM, amounts of goal-equivalent and non-goal-equivalent variability were afterwards determined and used to define an index providing information about the set of effective motor solutions relative to the GEM. The set was limited in OA compared to YA in treadmill walking alone, indicating that OA made less flexible use of motor abundance than YA. However, this differentiation between YA and OA disappeared when concurrently performing the cognitive task. It is proposed that OA might have benefited from cognitive compensation
Genetic Overexpression of NR2B Subunit Enhances Social Recognition Memory for Different Strains and Species
The ability to learn and remember conspecifics is essential for the establishment and maintenance of social groups. Many animals, including humans, primates and rodents, depend on stable social relationships for survival. Social learning and social recognition have become emerging areas of interest for neuroscientists but are still not well understood. It has been established that several hormones play a role in the modulation of social recognition including estrogen, oxytocin and arginine vasopression. Relatively few studies have investigated how social recognition might be improved or enhanced. In this study, we investigate the role of the NMDA receptor in social recognition memory, specifically the consequences of altering the ratio of the NR2B∶NR2A subunits in the forebrain regions in social behavior. We produced transgenic mice in which the NR2B subunit of the NMDA receptor was overexpressed postnatally in the excitatory neurons of the forebrain areas including the cortex, amygdala and hippocampus. We investigated the ability of both our transgenic animals and their wild-type littermate to learn and remember juvenile conspecifics using both 1-hr and 24-hr memory tests. Our experiments show that the wild-type animals and NR2B transgenic mice preformed similarly in the 1-hr test. However, transgenic mice showed better performances in 24-hr tests of recognizing animals of a different strain or animals of a different species. We conclude that NR2B overexpression in the forebrain enhances social recognition memory for different strains and animal species
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