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61.
Marina Quartu Maria Pina Serra Annalisa Manca Paolo Follesa Rossano Ambu Marina Del Fiacco 《International journal of developmental neuroscience》2003,21(6):309-320
The immunohistochemical occurrence of the high affinity neurotrophin (NT) receptors trkA, trkB, and trkC is shown in the pre-term newborn, infant, and adult human post-mortem cerebellum. Immunoreactive neuronal perikarya and processes were observed in all specimens examined, where they appeared unevenly distributed in the cerebellar cortical layers and deep nuclei, and showed regional differences among cerebellar lobules and folia. The trk receptor-antibodies, tested by Western blot on human cerebellum homogenates, revealed multiple immunoreactive bands for trkA and single bands for trkB and trkC. The results obtained show the tissue localization of the trk receptor-like immunoreactivity in the human cerebellum from prenatal to adult age. The analysis for codistribution of the receptors with the relevant ligand and among the receptors in discrete cortical and deep nuclei tissue fields shows a wide variety of conditions, from a good similarity in terms of type and density of labeled structures, to a lack of correspondence, and suggests the possibility of colocalization of trk receptors with the relevant neurotrophin and among them in the cerebellar cortex. These results sustain the concept that the neurotrophin trophic system participates in the development, differentiation, and maintenance of the human cerebellar connectivity and support the possibility of a multifactorial trophic support for the neurotrophins through target-derived and local mechanisms. 相似文献
62.
63.
Kallol Ray Chaudhuri Pablo Martinez-Martin Anthony H V Schapira Fabrizio Stocchi Kapil Sethi Per Odin Richard G Brown William Koller Paolo Barone Graeme MacPhee Linda Kelly Martin Rabey Doug MacMahon Sue Thomas William Ondo David Rye Alison Forbes Susanne Tluk Vandana Dhawan Annette Bowron Adrian J Williams Charles W Olanow 《Movement disorders》2006,21(7):916-923
Nonmotor symptoms (NMS) of Parkinson's disease (PD) are not well recognized in clinical practice, either in primary or in secondary care, and are frequently missed during routine consultations. There is no single instrument (questionnaire or scale) that enables a comprehensive assessment of the range of NMS in PD both for the identification of problems and for the measurement of outcome. Against this background, a multidisciplinary group of experts, including patient group representatives, has developed an NMS screening questionnaire comprising 30 items. This instrument does not provide an overall score of disability and is not a graded or rating instrument. Instead, it is a screening tool designed to draw attention to the presence of NMS and initiate further investigation. In this article, we present the results from an international pilot study assessing feasibility, validity, and acceptability of a nonmotor questionnaire (NMSQuest). Data from 123 PD patients and 96 controls were analyzed. NMS were highly significantly more prevalent in PD compared to controls (PD NMS, median = 9.0, mean = 9.5 vs. control NMS, median = 5.5, mean = 4.0; Mann-Whitney, Kruskal-Wallis, and t test, P < 0.0001), with PD patients reporting at least 10 different NMS on average per patient. In PD, NMS were highly significantly more prevalent across all disease stages and the number of symptoms correlated significantly with advancing disease and duration of disease. Furthermore, frequently, problems such as diplopia, dribbling, apathy, blues, taste and smell problems were never previously disclosed to the health professionals. 相似文献
64.
Treatment of Status Epilepticus in Adults: Guidelines of the Italian League Against Epilepsy 总被引:2,自引:1,他引:1
Fabio Minicucci †Giancarlo Muscas ‡Emilio Perucca §Giuseppe Capovilla Federico Vigevano ¶Paolo Tinuper 《Epilepsia》2006,47(S5):9-15
Summary: Status epilepticus (SE) is a medical emergency which can lead to significant morbidity and mortality and requires prompt diagnosis and treatment. SE is differentiated into generalized or partial SE on the basis of its electro-clinical manifestations. The guidelines for the management of SE produced by the Italian League against Epilepsy also distinguish three different stages of SE (initial, established and refractory), based on time elapsed since the onset of the condition and responsiveness to previously administered drugs. Treatment should be started as soon as possible, particularly in generalized convulsive SE, and should include general support measures, drugs to suppress epileptic activity and, whenever possible, treatments aimed at relieving the underlying (causative) condition. Benzodiazepines are the first line antiepileptic agents, and i.v. lorazepam is generally preferred because it is associated with a lower risk of early relapses. If benzodiazepines fail to control seizures, i.v. phenytoin is usually indicated, though i.v. phenobarbital or i.v. valproate may also be considered. Refractory SE requires admission to an intensive care unit (ICU) to allow adequate monitoring and support of respiratory, metabolic and hemodynamic functions and cerebral electrical activity. In refractory SE, general anesthesia may be required. Propofol and thiopental represent first line agents in this setting, after careful assessment of potential risks and benefits. 相似文献
65.
Alexandre Castro-Caldas Paul Delwaide Wolfgang Jost Marcelo Merello Adrian Williams Paolo Lamberti Miguel Aguilar Susanna Del Signore Pierre Cesaro 《Movement disorders》2006,21(4):500-509
Dopamine agonists have been recommended as early treatment for Parkinson's disease (PD), alone or combined with levodopa. Piribedil is a non-ergot selective D(2)/D(3) agonist with alpha(2) antagonist properties shown to be effective in the treatment of PD. This 12-month international, randomized, double-blind trial aimed to assess the efficacy of piribedil 150 mg versus bromocriptine 25 mg, in early combination with levodopa in Stage I to III PD patients. Motor efficacy was assessed using the Unified Parkinson's Disease Rating Scale (UPDRS III, Items 18-31) as improvement from baseline. Response rate was defined as a 30% improvement. Among the 425 randomly assigned patients, 178 were also included in a substudy on cognitive follow-up evaluated by a dysexecutive syndrome oriented battery. A relevant improvement in UPDRS III over the 12-month study duration was observed both in the piribedil and bromocriptine groups (-7.9 +/- 9.7 points from baseline versus -8.0 +/- 9.5; not significant [n.s.]) with a response rate of 58.4% and 55.3% (n.s.), respectively. Piribedil and bromocriptine resulted in similar improvement on all UPDRS III subscores. Piribedil patients required less levodopa dose increase than those on bromocriptine. Cognitive performance remained generally unchanged in both groups, with a significant effect of piribedil limited to the Wisconsin Card Sorting Test. An overall good tolerability of piribedil was observed. Early combination of piribedil 150 mg with levodopa resulted in significant long-term improvement of all motor symptoms in PD patients insufficiently controlled by levodopa alone. Taking into account both efficacy and acceptability in the long-term, piribedil proved in this bromocriptine controlled study to be an effective and safe treatment for PD. 相似文献
66.
By synthesizing and testing a part-structure, N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)ethylamine (3), derived from our previously reported high affinity sigma receptor ligands (1S,2R)-(-)-N-[2-(3,4-dichlorophenyl)-ethyl]-N-methyl-2-(1- pyrrolidinyl)cyclohexylamine [(-)-2] and (+)-2, we have identified a novel class of superpotent (subnanomolar affinity) sigma ligands specific for the sigma receptor labeled by [3H]-(+)-3-PPP. When 3 was tested for its capacity to displace [3H]-(+)-3-PPP from guinea pig brain membranes, it exhibited a Ki of 0.34 nM, which is better than either of its parent compounds (-)-2 (Ki = 1.3 nM) and (+)-2 (Ki = 6.0 nM). Other compounds related to 3 such as N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-homopiperidinyl)ethy lamine (19) exhibited Ki = 0.17 nM [( 3H]-(+)-3-PPP). The determinants for high sigma receptor affinity of 3 were examined by manipulation of this structure in a number of different ways. The high efficacy of these compounds for the sigma receptor, their relative chemical simplicity and ease of synthesis, and their high degree of selective identifies N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)ethylamine (3) and related compounds as a highly promising base for determination of the functional role of sigma receptors as well as the development of novel therapeutic agents. 相似文献
67.
It is well known that the number of follicles in the mammalian ovary decreases with age. In light of previous data from this laboratory showing age-related alterations in the secretion and production of follicle-stimulating hormone (FSH) in rats by 5-6 months of age, one objective of the present study was to determine if alterations in FSH secretion were accompanied by changes in the number of antral follicles. A second objective of this study was to determine whether or not interruption of cyclic activity by continuous progesterone (P) treatment could decelerate age-associated changes in FSH secretion possibly by retarding the depletion of follicles through ovulation. For this study, one group of 4-day cycling, 7-week-old rats received one empty Silastic implant while another group received 3-40 mm implants containing 30 mm crystalline P. Implants were replaced every 2 weeks until the animals were 5 months old. Progesterone-implanted rats were acyclic during treatment exhibiting predominantly leukocytic vaginal smears. Regular 4-day cycles resumed when P implants were withdrawn (rats approximately 5-6-months-old). A group of 2-3-month-old untreated rats were used for comparison. As expected from our previous results, serum FSH levels at 1600 h on estrus were significantly higher in 5-6-month-old rats receiving empty capsules than in younger rats. Serum FSH concentrations measured in P-treated rats at this time also were significantly higher than levels of this gonadotropin measured in younger rats. Ovaries of older control and P-treated rats contained significantly fewer medium and large antral follicles (greater than 250 microns) than the ovaries of younger rats despite the curtailment of estrous cyclicity and ovulation by continuous P treatment. Interestingly, P treatment prevented the age-associated decrease in thymus weight. Taken together, the present observations suggest that a decrease in the number of growing follicles may be a factor contributing to early age-related alterations in FSH secretion. Furthermore, the prevention (at least temporarily) of age-related thymic involution by P treatment may be indicative of an interrelationship between thymic and reproductive aging. 相似文献
68.
Claudio Babiloni Giovanni Frisoni Mircea Steriade Lorena Bresciani Giuliano Binetti Claudio Del Percio Cristina Geroldi Carlo Miniussi Flavio Nobili Guido Rodriguez Filippo Zappasodi Tania Carfagna Paolo M Rossini 《Clinical neurophysiology》2006,117(5):1113-1129
OBJECTIVE: A relationship between brain atrophy and delta rhythmicity (1.5-4 Hz) has been previously explored in Alzheimer's disease (AD) subjects [Fernandez A, Arrazola J, Maestu F, Amo C, Gil-Gregorio P, Wienbruch C, Ortiz T. Correlations of hippocampal atrophy and focal low-frequency magnetic activity in Alzheimer disease: volumetric MR imaging-magnetoencephalographic study. Am J Neuroradiol. 2003 24(3):481-487]. In this study, we tested the hypothesis that such a relationship does exist not only in AD patients but also across the continuum of subjects with mild cognitive impairment (MCI) and AD. METHODS: Resting, eyes-closed EEG data were recorded in 34 MCI and 65 AD subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. Cortical EEG sources were correlated with MR-based measurements of lobar brain volume (white and gray matter). RESULTS: A negative correlation was observed between the frontal white matter and the amplitude of frontal delta sources (2-4 Hz) across MCI and AD subjects. CONCLUSIONS: These results confirmed for the first time the hypothesis that the sources of resting delta rhythms (2-4 Hz) are correlated with lobar brain volume across MCI and AD subjects. SIGNIFICANCE: The present findings support, at least at group level, the 'transition hypothesis' of brain structural and functional continuity between MCI and AD. 相似文献
69.
Ruggero de Paulis Fabrizio Tomai Fabio Bertoldo Anna S Ghini Raffaele Scaffa Paolo Nardi Luigi Chiariello 《European journal of cardio-thoracic surgery》2004,26(1):66-72
OBJECTIVES: The sinuses of Valsalva are known to contribute to the normal function of the aortic valve. Little is known about their role in promoting coronary artery blood flow. The aim of this study was to compare coronary artery flow characteristics among patients undergoing a Bentall operation by means of a conventional cylindrical Dacron conduit or with a new conduit with pseudosinuses of Valsalva or in patients retaining their natural sinuses of Valsalva after aortic valve and supracoronary ascending aorta replacement. METHODS: One year after a Bentall procedure with a standard cylindrical Dacron conduit (7 patients, group A) or with the new conduit (7 patients, group B), or after aortic valve and ascending aortic replacement (control group, 7 patients, group C) coronary flow velocity reserve and diastolic to systolic time integral ratio at baseline and after maximal hyperemia (with 40 microg of adenosine) were assessed by using a 0.014-in. Doppler guidewire positioned in the middle portion of the left anterior descending coronary artery. All patients were in NYHA class I, sinus rhythm and free of coronary disease. RESULTS: Arterial blood pressures and heart rate were comparable among groups. Intracoronary Doppler measurements did not show any significant difference in coronary vascular reserve between the three groups (3.6+/-0.4 vs 3.1+/-0.7 vs 3.7+/-0.5, P = 0.2). A greater diastolic component at baseline was present in group B patients (5.5+/-1.9 vs 3.5+/-0.9 in group A and 3.7+/-0.9 in group C, P = 0.024). After maximal hyperemia the diastolic component increased slightly in group A patients (8%) while both in groups B and C significantly decreased (-15 and -20%, respectively) (P = 0.017). CONCLUSIONS: The presence of pseudosinuses of Valsalva does not influence coronary flow reserve. After maximal coronary vasodilation the increase in the systolic component of coronary flow is more evident in the presence of sinuses or pseudosinuses of Valsalva, thus suggesting that coronary flow pattern may be affected by the presence of sinuses. 相似文献
70.