87 resultados para Conscious Monkey
Resumo:
Retroviruses are both powerful evolutionary forces and dangerous threats to genome integrity. As such, they have imposed strong selective pressure on their hosts, notably triggering the emergence of restriction factors, such as TRIM5 alpha, that act as potent barriers to their cross-species transmission. TRIM5 alpha orthologues from different primates have distinct retroviral restriction patterns, largely dictated by the sequence of their C-terminal PRYSPRY domain, which binds the capsid protein of incoming virions. Here, by combining genetic and functional analyses of human and squirrel monkey TRIM5 alpha, we demonstrate that the coiled-coil domain of this protein, thus far essentially known for mediating oligomerization, also conditions the spectrum of antiretroviral activity. Furthermore, we identify three coiled-coil residues responsible for this effect, one of which has been under positive selection during primate evolution, notably in New World monkeys. These results indicate that the PRYSPRY and coiled-coil domains cooperate to determine the specificity of TRIM5 alpha-mediated capture of retroviral capsids, shedding new light on this complex event.
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In the context of an autologous cell transplantation study, a unilateral biopsy of cortical tissue was surgically performed from the right dorsolateral prefrontal cortex (dlPFC) in two intact adult macaque monkeys (dlPFC lesioned group), together with the implantation of a chronic chamber providing access to the left motor cortex. Three other monkeys were subjected to the same chronic chamber implantation, but without dlPFC biopsy (control group). All monkeys were initially trained to perform sequential manual dexterity tasks, requiring precision grip. The motor performance and the prehension's sequence (temporal order to grasp pellets from different spatial locations) were analysed for each hand. Following the surgery, transient and moderate deficits of manual dexterity per se occurred in both groups, indicating that they were not due to the dlPFC lesion (most likely related to the recording chamber implantation and/or general anaesthesia/medication). In contrast, changes of motor habit were observed for the sequential order of grasping in the two monkeys with dlPFC lesion only. The changes were more prominent in the monkey subjected to the largest lesion, supporting the notion of a specific effect of the dlPFC lesion on the motor habit of the monkeys. These observations are reminiscent of previous studies using conditional tasks with delay that have proposed a specialization of the dlPFC for visuo-spatial working memory, except that this is in a different context of "free-will", non-conditional manual dexterity task, without a component of working memory.
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Lentiviral vectors infect quiescent cells and allow for the delivery of genes to discrete brain regions. The present study assessed whether stable lentiviral gene transduction can be achieved in the monkey nigrostriatal system. Three young adult Rhesus monkeys received injections of a lentiviral vector encoding for the marker gene beta galatosidase (beta Gal). On one side of the brain, each monkey received multiple lentivirus injections into the caudate and putamen. On the opposite side, each animal received a single injection aimed at the substantia nigra. The first two monkeys were sacrificed 1 month postinjection, while the third monkey was sacrificed 3 months postinjection. Robust incorporation of the beta Gal gene was seen in the striatum of all three monkeys. Stereological counts revealed that 930,218; 1,192,359; and 1,501,217 cells in the striatum were beta Gal positive in monkeys 1 (n = 2) and 3 (n = 1) months later, respectively. Only the third monkey had an injection placed directly into the substantia nigra and 187,308 beta Gal-positive cells were identified in this animal. The injections induced only minor perivascular cuffing and there was no apparent inflammatory response resulting from the lentivirus injections. Double label experiments revealed that between 80 and 87% of the beta Gal-positive cells were neurons. These data indicate that robust transduction of striatal and nigral cells can occur in the nonhuman primate brain for up to 3 months. Studies are now ongoing testing the ability of lentivirus encoding for dopaminergic trophic factors to augment the nigrostriatal system in nonhuman primate models of Parkinson's disease.
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Neuropeptide Y (NPY) is a vasoconstrictor peptide possibly involved in the regulation of renal sodium handling and renin release. This investigation was undertaken to assess in conscious normotensive rats the acute effects of a non-pressor dose of NPY on renal plasma flow, glomerular filtration rate, sodium excretion and plasma renin activity. Experiments were also performed during concomitant beta-adrenoceptor stimulation with isoproterenol. NPY per se had no effect on the studied parameters. Renal plasma flow was increased by isoproterenol and was significantly higher when the beta-adrenoceptor stimulant was infused alone (13.4 +/- 2.1 ml/min, p < 0.05, mean +/- SEM) that when administered together with NPY (7.2 +/- 2.0 ml/min). This was also true for glomerular filtration rate (3.3 +/- 0.3 vs. 1.8 +/- 0.3 ml/min, p < 0.01) and plasma renin activity (6.3 +/- 1.7 vs. 2.1 +/- 0.4 ng Ang I/ml/h, p < 0.05). Our data however do not allow to deduce whether the inhibitory effect of NPY on isoproterenol-induced renin release is mediated by changes in intrarenal hemodynamics or a direct effect on juxtaglomerular cells.
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We analyzed the coherence of electroencephalographic (EEG) signals recorded symmetrically from the two hemispheres, while subjects (n = 9) were viewing visual stimuli. Considering the many common features of the callosal connectivity in mammals, we expected that, as in our animal studies, interhemispheric coherence (ICoh) would increase only with bilateral iso-oriented gratings located close to the vertical meridian of the visual field, or extending across it. Indeed, a single grating that extended across the vertical meridian significantly increased the EEG ICoh in normal adult subjects. These ICoh responses were obtained from occipital and parietal derivations and were restricted to the gamma frequency band. They were detectable with different EEG references and were robust across and within subjects. Other unilateral and bilateral stimuli, including identical gratings that were effective in anesthetized animals, did not affect ICoh in humans. This fact suggests the existence of regulatory influences, possibly of a top-down kind, on the pattern of callosal activation in conscious human subjects. In addition to establishing the validity of EEG coherence analysis for assaying cortico-cortical connectivity, this study extends to the human brain the finding that visual stimuli cause interhemispheric synchronization, particularly in frequencies of the gamma band. It also indicates that the synchronization is carried out by cortico-cortical connection and suggests similarities in the organization of visual callosal connections in animals and in man.
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BACKGROUND: After sub-total hemi-section of cervical cord at level C7/C8 in monkeys, the ipsilesional hand exhibited a paralysis for a couple of weeks, followed by incomplete recovery of manual dexterity, reaching a plateau after 40-50 days. Recently, we demonstrated that the level of the plateau was related to the size of the lesion and that progressive plastic changes of the motor map in the contralesional motor cortex, particularly the hand representation, took place following a comparable time course. The goal of the present study was to assess, in three macaque monkeys, whether the hand representation in the ipsilesional primary motor cortex (M1) was also affected by the cervical hemi-section.¦RESULTS: Unexpectedly, based on the minor contribution of the ipsilesional hemisphere to the transected corticospinal (CS) tract, a considerable reduction of the hand representation was also observed in the ipsilesional M1. Mapping control experiments ruled out the possibility that changes of motor maps are due to variability of the intracortical microstimulation mapping technique. The extent of the size reduction of the hand area was nearly as large as in the contralesional hemisphere in two of the three monkeys. In the third monkey, it represented a reduction by a factor of half the change observed in the contralesional hemisphere. Although the hand representation was modified in the ipsilesional hemisphere, such changes were not correlated with a contribution of this hemisphere to the incomplete recovery of the manual dexterity for the hand affected by the lesion, as demonstrated by reversible inactivation experiments (in contrast to the contralesional hemisphere). Moreover, despite the size reduction of M1 hand area in the ipsilesional hemisphere, no deficit of manual dexterity for the hand opposite to the cervical hemi-section was detected.¦CONCLUSION: After cervical hemi-section, the ipsilesional motor cortex exhibited substantial reduction of the hand representation, whose extent did not match the small number of axotomized CS neurons. We hypothesized that the paradoxical reduction of hand representation in the ipsilesional hemisphere is secondary to the changes taking place in the contralesional hemisphere, possibly corresponding to postural adjustments and/or re-establishing a balance between the two hemispheres.
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1. The purpose of this study was to examine the contribution of the sympatho-adrenomedullary system to the blood pressure response to an intravenous bolus of thyrotropin-releasing hormone (TRH) in conscious medullectomized and sham-operated rats. 2. The peak pressor effect of 0.5 mg TRH was significantly increased in rats having no adrenal medulla (+24.2 +/- 1.6 mmHg, mean +/- s.e.m., P < 0.01) as compared to sham-operated animals (+12.2 +/- 3.0 mmHg). 3. Blockade of alpha-adrenergic receptors with phentolamine abolished the pressor effect of TRH in control rats (+2.1 +/- 1.9 mmHg) but did not attenuate the blood pressure response of medullectomized rats (+21.5 +/- 4.7 mmHg). In contrast, beta-blockade with propranolol blunted the blood pressure responsiveness of rats subjected to adrenal medullectomy (+12.4 +/- 2.6 mmHg) but did not modify the effect of TRH in sham-operated controls (+10.9 +/- 2.9 mmHg). 4. The direct in vitro effect of TRH on isolated mesenteric rat arteries was also evaluated. TRH did not induce contractions of isolated arteries. 5. These results suggest that in rats with intact adrenals, the pressor effect of intravenous TRH is mediated primarily by a stimulation of alpha-adrenergic receptors. Adrenal medullectomy appears to enhance the blood pressure response to intravenous TRH. Activation of cardiac beta-adrenoceptors seems to contribute to the blood pressure increasing effect of intravenous TRH in medullectomized animals.
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Depending on the context, Christians, Muslims and Jews have constructed their own religion, perceived the religions of others, and articulated relations between religions in different ways. This paper examines the rise in history of the three communities, which came to identify themselves through their religions and have been highly sensitive to differences. It indicates common features and parallels of which adherents may have been more or less conscious. The central question in such research is what persons and groups mean in particular situations when they call themselves Christian, Muslim or Jewish. The variety of personal and group identities in the three religious communities has been concealed partly by religious leaderships concerned with the survival of their flocks, and partly by the use of the general concepts of Christianity, Islam and Judaism with which believers have been called to identify. These concepts have shut people into separate religious pigeonholes and could thus be used to support ethnic, social and other rivalries. This pigeonholing has also confronted more spiritually-oriented people with problems of social identity, religious belonging and spiritual authenticity.
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Induction of drug-metabolizing enzymes (DMEs) is highly species-specific and can lead to drug-drug interaction and toxicities. In this series of studies we tested the species specificity of the antidiabetic drug development candidate and mixed peroxisome proliferator-activated receptor (PPAR) alpha/gamma agonist (S)-4-O-tolylsulfanyl-2-(4-trifluormethyl-phenoxy)-butyric acid (EMD 392949, EMD) with regard to the induction of gene expression and activities of DMEs, their regulators, and typical PPAR target genes. EMD clearly induced PPARalpha target genes in rats in vivo and in rat hepatocytes but lacked significant induction of DMEs, except for cytochrome P450 (P450) 4A. CYP2C and CYP3A were consistently induced in livers of EMD-treated monkeys. Interestingly, classic rodent peroxisomal proliferation markers were induced in monkeys after 17 weeks but not after a 4-week treatment, a fact also observed in human hepatocytes after 72 h but not 24 h of EMD treatment. In human hepatocyte cultures, EMD showed similar gene expression profiles and induction of P450 activities as in monkeys, indicating that the monkey is predictive for human P450 induction by EMD. In addition, EMD induced a similar gene expression pattern as the PPARalpha agonist fenofibrate in primary rat and human hepatocyte cultures. In conclusion, these data showed an excellent correlation of in vivo data on DME gene expression and activity levels with results generated in hepatocyte monolayer cultures, enabling a solid estimation of human P450 induction. This study also clearly highlighted major differences between primates and rodents in the regulation of major inducible P450s, with evidence of CYP3A and CYP2C inducibility by PPARalpha agonists in monkeys and humans.
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Objectives. Biased thinking (to some extent overlapping with the concepts of cognitive distortions and cognitive errors) is a key concept in cognitive therapy of Borderline Personality Disorder (BPD). Specific contents and cognitive processes related to BPD functioning are known. However, most studies are based on self-report measures which present a number of important limitations, in particular the difficulty in assessing non-conscious processes infused by affect. So far, no studies were conducted using valid observer-rated methodology addressing the question of biased thinking in BPD as it unfolds spontaneously in session. Design. This is a controlled interview study comparing two matched groups, BPD patients and healthy controls. Methods. A total of N= 25 clinical dynamic interviews with patients presenting with BPD were transcribed and rated using the Cognitive Errors Rating Scale (Drapeau, Perry, & Dunkley, 2008); their cognitive profiles were compared to those of N= 25 healthy controls who underwent the same procedure. Results. Overall, results indicated that no between-group difference in the frequency of specific biases was found. However, heightened levels of negative cognitive biases, in particular over-generalizing and fortune-telling, were associated with BPD. Furthermore, negative over-generalizing was associated with the number of BPD symptoms. Conclusions. These results have high levels of ecological validity and are promising for the refinement of cognitive theory of BPD. Clinical implications for assessment and intervention are discussed.
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Propofol is progressively replacing benzodiazepines for sedation during endoscopy, even when the sedation is administered by non-anesthesiologists. Propofol ensures a more rapid induction of sedation and recovery and, in certain conditions, higher patient satisfaction and improved quality of endoscopic examination. Specific training is required to use this drug. Patients at risk of complications should be identified before the endoscopy to optimize patient management with an anesthesiologist. After sedation, psychomotor recovery is faster with propofol compared to traditional sedation agents but tasks requiring particular attention (eg, driving) should be avoided. It is important to advise patients of these restrictions in advance.
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BACKGROUND: Prehospital oligoanalgesia is prevalent among trauma victims, even when the emergency medical services team includes a physician. We investigated if not only patients' characteristics but physicians' practice variations contributed to prehospital oligoanalgesia. METHODS: Patient records of conscious adult trauma victims transported by our air rescue helicopter service over 10 yr were reviewed retrospectively. Oligoanalgesia was defined as a numeric rating scale (NRS) >3 at hospital admission. Multilevel logistic regression analysis was used to predict oligoanalgesia, accounting first for patient case-mix, and then physician-level clustering. The intraclass correlation was expressed as the median odds ratio (MOR). RESULTS: A total of 1202 patients and 77 physicians were included in the study. NRS at the scene was 6.9 (1.9). The prevalence of oligoanalgesia was 43%. Physicians had a median of 5.7 yr (inter-quartile range: 4.2-7.5) of post-graduate training and 27% were female. In our multilevel analysis, significant predictors of oligoanalgesia were: no analgesia [odds ratio (OR) 8.8], National Advisory Committee for Aeronautics V on site (OR 4.4), NRS on site (OR 1.5 per additional NRS unit >4), female physician (OR 2.0), and years of post-graduate experience [>4.0 to ≤5.0 (OR 1.3), >3.0 to ≤4.0 (OR 1.6), >2.0 to ≤3.0 (OR 2.6), and ≤2.0 yr (OR 16.7)]. The MOR was 2.6, and was statistically significant. CONCLUSIONS: Physicians' practice variations contributed to oligoanalgesia, a factor often overlooked in analyses of prehospital pain management. Further exploration of the sources of these variations may provide innovative targets for quality improvement programmes to achieve consistent pain relief for trauma victims.
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INTRODUCTION. Patients admitted in Intensive Care Unit (ICU) from general wards are more severe and have a higher mortality than those admitted from emergency department as reported [1]. The majority of them develop signs of instability (e.g. tachypnea, tachycardia, hypotension, decreased oxygen saturation and change in conscious state) several hours before ICU admission. Considering this fact and that in-hospital cardiac arrests and unexpected deaths are usually preceded by warning signs, immediate on site intervention by specialists may be effective. This gave an impulse to medical emergency team (MET) implementation, which has been shown to decrease cardiac arrest, morbidity and mortality in several hospitals. OBJECTIVES AND METHODS. In order to verify if the same was true in our hospital and to determine if there was a need for MET, we prospectively collected all non elective ICU admissions of already hospitalized patients (general wards) and of patients remaining more than 3 h in emergency department (considered hospitalized). Instability criteria leading to MET call correspond to those described in the literature. The delay between the development of one criterion and ICU admission was registered. RESULTS. During an observation period of 12 months, 321 patients with our MET criteria were admitted to ICU. 88 patients came from the emergency department, 115 from the surgical and 113 from the medical ward. 65% were male. The median age was 65 years (range 17-89). The delay fromMETcriteria development to ICU admission was higher than 8 h in 155 patients, with a median delay of 32 h and a range of 8.4 h to 10 days. For the remaining 166 patients, an early MET criterion was present up to 8 h (median delay 3 h) before ICU admission. These results are quite concordant with the data reported in the literature (ref 1-8). 122 patients presented signs of sepsis or septic shock, 70 patients a respiratory failure, 58 patients a cardiac emergency. Cardiac arrest represent 5% of our collective of patients. CONCLUSIONS.Similar to others observations, the majority of hospitalized patients admitted on emergency basis in our ICU have warning signs lasting for several hours. More than half of them were unstable for more than 8 h. This shows there is plenty of time for early acute management by dedicated and specialized team such as MET. However, further studies are required to determine if MET implementation can reduce in-hospital cardiac arrests and influence the morbidity, the length of stay and the mortality.
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We previously reported that nuclear grade assignment of prostate carcinomas is subject to a cognitive bias induced by the tumor architecture. Here, we asked whether this bias is mediated by the non-conscious selection of nuclei that "match the expectation" induced by the inadvertent glance at the tumor architecture. 20 pathologists were asked to grade nuclei in high power fields of 20 prostate carcinomas displayed on a computer screen. Unknown to the pathologists, each carcinoma was shown twice, once before a background of a low grade, tubule-rich carcinoma and once before the background of a high grade, solid carcinoma. Eye tracking allowed to identify which nuclei the pathologists fixated during the 8 second projection period. For all 20 pathologists, nuclear grade assignment was significantly biased by tumor architecture. Pathologists tended to fixate on bigger, darker, and more irregular nuclei when those were projected before kigh grade, solid carcinomas than before low grade, tubule-rich carcinomas (and vice versa). However, the morphometric differences of the selected nuclei accounted for only 11% of the architecture-induced bias, suggesting that it can only to a small part be explained by the unconscious fixation on nuclei that "match the expectation". In conclusion, selection of « matching nuclei » represents an unconscious effort to vindicate the gravitation of nuclear grades towards the tumor architecture.
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BACKGROUND: Postanoxic status epilepticus (PSE) is considered a predictor of fatal outcome and therefore not intensively treated; however, some patients have had favorable outcomes. The aim of this study was to identify favorable predictors for awakening beyond vegetative state in PSE. METHODS: We studied six subjects treated with hypothermia improving beyond vegetative state after cerebral anoxia, despite PSE. They were among a cohort of patients treated for anoxic encephalopathy with therapeutic hypothermia in our institution between October 1999 and May 2006 (retrospectively, 3/107 patients) and June 2006 and May 2008 (prospectively, 3/74 patients). PSE was defined by clinical and EEG criteria. Outcome was assessed according to the Glasgow-Pittsburgh Cerebral Performance Categories (CPC). RESULTS: All improving patients had preserved brainstem reflexes, cortical somatosensory evoked potentials, and reactive EEG background during PSE. Half of them had myoclonic PSE, while three had nonconvulsive PSE. In the prospective arm, 3/28 patients with PSE showed this clinical-electrophysiologic profile; all awoke. Treatments consisted of benzodiazepines, various antiepileptic drugs, and propofol. One subject died of pneumonia in a minimally conscious state, one patient returned to baseline (CPC1), three had moderate impairment (CPC2), and one remained dependent (CPC3). Patients with nonconvulsive PSE showed a better prognosis than subjects with myoclonic PSE (p = 0.042). CONCLUSION: Patients with postanoxic status epilepticus and preserved brainstem reactions, somatosensory evoked potentials, and EEG reactivity may have a favorable outcome if their condition is treated as status epilepticus.