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31.
Grabski K Lamalle L Vilain C Schwartz JL Vallée N Tropres I Baciu M Le Bas JF Sato M 《Human brain mapping》2012,33(10):2306-2321
Compared with complex coordinated orofacial actions, few neuroimaging studies have attempted to determine the shared and distinct neural substrates of supralaryngeal and laryngeal articulatory movements when performed independently. To determine cortical and subcortical regions associated with supralaryngeal motor control, participants produced lip, tongue and jaw movements while undergoing functional magnetic resonance imaging (fMRI). For laryngeal motor activity, participants produced the steady-state/i/vowel. A sparse temporal sampling acquisition method was used to minimize movement-related artifacts. Three main findings were observed. First, the four tasks activated a set of largely overlapping, common brain areas: the sensorimotor and premotor cortices, the right inferior frontal gyrus, the supplementary motor area, the left parietal operculum and the adjacent inferior parietal lobule, the basal ganglia and the cerebellum. Second, differences between tasks were restricted to the bilateral auditory cortices and to the left ventrolateral sensorimotor cortex, with greater signal intensity for vowel vocalization. Finally, a dorso-ventral somatotopic organization of lip, jaw, vocalic/laryngeal, and tongue movements was observed within the primary motor and somatosensory cortices using individual region-of-interest (ROI) analyses. These results provide evidence for a core neural network involved in laryngeal and supralaryngeal motor control and further refine the sensorimotor somatotopic organization of orofacial articulators. 相似文献
32.
Krystyna Gołembiowska Jadwiga Wardas Karolina Noworyta-Sokołowska Katarzyna Kamińska Anna Górska 《Neurotoxicity research》2013,24(1):29-40
The study shows effects of the nonselective adenosine A1/A2A receptor antagonist caffeine and the selective A2A receptor antagonist KW6002 on LPS-induced changes in the extracellular levels of dopamine (DA), glutamate, adenosine, hydroxyl radical, and A2A receptor density in the rat striatum. Intrastriatal LPS (10 μg) injection decreased extracellular level of DA and increased the level of adenosine, glutamate, and hydroxyl radical on the ipsilateral side 24 h after LPS administration. Caffeine (10 and 20 mg/kg i.p.) and KW6002 (1.5 and 3 mg/kg i.p.) given once daily for 6 days and on the 7th day 2 h before and 4 h after LPS injection reversed the LPS-induced changes in extracellular levels of DA, adenosine, glutamate, and hydroxyl radical production. Moreover, LPS-induced decrease in the striatal A2A receptor density was increased by caffeine and KW6002. In order to show the late LPS effect on oxidative damage of DA neurons, the contents of DA, DOPAC, HVA, and hydroxyl radical were determined 72 h after LPS (10 μg) administration into both striata. LPS decreased striatal and substantia nigra content of DA, DOPAC, and HVA while increased striatal but not nigral content of hydroxyl radical. Caffeine (20 mg/kg) and KW60002 (3 mg/kg) given once daily for 6 days and on the 7th day 2 h before and 4 h after intrastriatal injection of LPS normalized the content of DA and its metabolites in both brain regions as well as decreased LPS-induced increase in the striatal level of hydroxyl radical. In conclusion, our data demonstrated antioxidant effects of caffeine and KW6002 in the inflammatory model of PD. 相似文献
33.
Presynaptic depolarization of cutaneous afferents has been investigated in the sacral cord of decerebrate cats before and after spinal cord transection. In the decerebrate state the central terminals of caudal femoral cutaneous nerve are depolarized by ipsilateral volleys entering the cord via sacral and lumbar dorsal roots. A significant increase of depolarization occurring after severing the cord indicates that there is tonic decerebrate inhibition of presynaptic depolarization in terminals of caudal femoral cutaneous nerve. In contrast to this finding, presynaptic depolarization evoked in the central terminals of the pudendal nerve by ipsilateral volleys entering the cord through sacral and lumbar dorsal roots is not subjected to decerebrate inhibitory control. It is suggested that differential inhibitory control of depolarization in the central terminals of cutaneous nerves in the sacral cord is related to the intraspinal course of their fibres, to differences in the receptor types involved, and to the location of their innervation fields. In more than half of the decerebrate preparations stimulation of the central terminals of cutaneous afferents through microelectrodes evokes antidromic spikes appearing simultaneously in ipsi- and contralateral nerves. The time course of bilateral excitability changes is similar on both sides of the cord. It is assumed that presynaptic effects are transmitted to the contralateral side by collaterals of ipsilateral cutaneous afferents. 相似文献
34.
Carpenter KJ Sen S Matthews EA Flatters SL Wozniak KM Slusher BS Dickenson AH 《Neuropeptides》2003,37(5):298-306
N-Acetylaspartylglutamate (NAAG) is a peptide neurotransmitter present in the brain and spinal cord. It is hydrolysed by glutamate carboxypeptidase II (GCPII); thus, the GCP-II inhibitor 2-[phosphono-methyl]-pentanedioic acid (2-PMPA) protects endogenous NAAG from degradation, allowing its effects to be studied in vivo. We recorded the effect of spinal 2-PMPA (50-1000 microg) on the electrical-evoked activity of dorsal horn neurones in normal and carrageenan-inflamed animals, and in the spinal nerve ligation (SNL) model of neuropathy and sham-operated animals. In normal animals, 1000 microg 2-PMPA selectively inhibited noxious-evoked activity (input, post-discharge and C- and Adelta-fibre-evoked responses), and not low threshold Abeta-fibre-evoked responses. After carrageenan inflammation, the lower dose of 100 microg 2-PMPA inhibited input, post-discharge, C- and Adelta-fibre-evoked responses by a significantly greater amount than the same dose in normal animals. 2-PMPA inhibited neuronal responses less consistently in sham-operated and SNL animals, and effects were not significantly different from those seen in normal animals. NAAG is an agonist at the inhibitory metabotropic glutamate receptor mGluR3, and 2-PMPA may inhibit nociceptive transmission in normal animals by elevating synaptic NAAG levels, allowing it to activate mGluR3 and thus reducing transmitter release from afferent nerve terminals. mGluR3 expression in the superficial dorsal horn is upregulated after peripheral inflammation, perhaps explaining the greater inhibition of neuronal responses we observed after carrageenan inflammation. These results support an important role of endogenous NAAG in the spinal processing of noxious information. 相似文献
35.
Walkowiak J Nousia-Arvanitakis S Agguridaki C Fotoulaki M Strzykala K Balassopoulou A Witt M Herzig KH 《Journal of pediatric gastroenterology and nutrition》2003,36(4):474-478
BACKGROUND: A progressive decline in pancreatic function is possible in cystic fibrosis (CF) patients with exocrine pancreatic sufficiency. The secretin-cholecystokinin test is invasive and not acceptable as a repeatable procedure for children. Steatorrhea, conversely, has low sensitivity. Therefore, the aim of the present study was to evaluate the usefulness of the noninvasive fecal elastase-1 (E1) test for the longitudinal assessment of exocrine pancreatic function (EPF) in pancreatic-sufficient (PS) CF patients. METHODS: One hundred eighty-four CF patients were included in the study. In all subjects, E1 concentrations and fecal fat excretion were measured. PS patients were followed for 5 years. RESULTS: At the beginning of the study, 35 (19.0%) CF patients were PS, and 32 (17.4%) had normal E1 concentrations. Longitudinal measurements of E1 concentrations in PS patients with CF demonstrated stable enzyme output in 27 and gradual decrease in 8. The decrease was rapid in five infant patients and gradual in three older patients. The decrease of E1 concentrations preceded the appearance of steatorrhea in all eight subjects. CONCLUSIONS: The decline of EPF in patients with CF appears more frequently during the first months and years of life. However, late PS to pancreatic-insufficient (PI) conversion is also possible. The appearance of maldigestion is preceded by the decrease of fecal E1 concentration. Thus, the fecal E1 test is a helpful screening tool for the longitudinal assessment of declining EPF in PS patients with CF to demonstrate pancreatic deterioration. In suspected patients, fecal fat excretion should be assessed. 相似文献
36.
Skotnicka-Klonowicz G Bagłaj M Sawicz-Birkowska K Balcerska A Dembowska B Szymik-Kantorowicz S Madziara W 《Medycyna wieku rozwojowego》2003,7(3):347-357
We present the results of treatment of kidney tumours in newborns and infants aged less than 6 months, in the years 1993-2000, from the Nephroblastoma Committee of the Polish Paediatric Group of Solid Tumours (PPGGL). We have analysed the diagnostic and treatment results in the group of 31 children aged 0 to 6 months. For 19 children registered between 1993 and 1996, event-free survival (EFS) and overall survival (AS) were assessed. Among 450 children registered between 1993 and 2000 by PPGGL and treated for kidney tumours, there were 31 (7.1%) newborns and infants aged below 6 months. The accuracy of diagnosis based on imaging studies was 97%. Only in one child the initial diagnosis of kidney tumour was not confirmed; cystic degeneration of kidney was finally established. The tumours removed during surgery were small, with average size 213 cm3, and in half of the cases the size of the tumour did not exceed 165 cm3. Primary complete excision of the tumour was performed in 21 children (67.7%). In 10 cases histopathology confirmed mesoblastic nephroma, in 19 cases nephroblastoma and in 2 cases sarcoma clarocellulare. In 10 infants (32.2%) with nephroblastoma delayed surgery preceded by chemotherapy was performed. Indications for initial preoperative chemotherapy comprised: tumour in a single kidney, tumour in a horseshoe kidney, preoperative diagnostic biopsy of the tumour and large tumour in neonates older than 3 months. In almost 70% of the children the stage of advancement was low (stage I and IIN-). Histopathology of excised tumours confirmed in 42% of cases low risk, and in 51.6% intermediate risk. Intraoperative complications occurred in 5 infants (16%). The tolerance of reduced chemotherapy by the infants was good. AS was 100%. ESF for the 19 children registered for nephroblastoma between 1993 and 1996 for all stages of advancement and types of histology was 94.75%. Conclusions: 1) Mesoblastic nephroma and low risk nephroblastoma are the most common tumours in children within the first three years of life. 2) The results of treatment of nephroblastoma in the youngest children (below 6 months of age) are the most favourable and represent world standards.3) Surgical complications in children operated primarily for nephroblastoma indicate the need of performing such operations in academic centres, specialised in newborn surgery. 4) In infants with extensive kidney tumours older than 3 months, primarily considered as inoperative, individual induction chemotherapy should be taken into account. 相似文献
37.
Gawron W Pośpiech L Noczyńska A Orendorz-Fraczkowska K 《Journal of pediatric endocrinology & metabolism : JPEM》2004,17(1):27-32
Thyroid gland diseases resulting from an autoimmunological process may influence the hearing organ. The aim of this study was to assess peripheral and central parts of the hearing organ in children with Hashimoto's thyroiditis. Thirty children (mean age 14.9 years) with Hashimoto's thyroiditis were examined. Patients were euthyroid, and presented high blood concentration of antithyroperoxidase (ATPO) antibodies. Pure tone audiometry, tympanometry, otoacoustic emissions (DPOAEs), and brain auditory evoked potentials (BAEPs) were performed. None of the patients had any complaints about hearing acuity; pure tone audiometry, tympanometry, and DPOAEs were normal in all patients. There were considerable disturbances in auditory nerve and brainstem neural conduction in BAEPs. There was positive correlation between the blood concentration of ATPOA and the extent of the disturbances in the central part of the hearing organ. One should consider the possible presence of subclinical Hashimoto's encephalopathy affecting the central part of the auditory organ. 相似文献
38.
Vilse, a conserved Rac/Cdc42 GAP mediating Robo repulsion in tracheal cells and axons 总被引:3,自引:0,他引:3
Lundström A Gallio M Englund C Steneberg P Hemphälä J Aspenström P Keleman K Falileeva L Dickson BJ Samakovlis C 《Genes & development》2004,18(17):2161-2171
Slit proteins steer the migration of many cell types through their binding to Robo receptors, but how Robo controls cell motility is not clear. We describe the functional analysis of vilse, a Drosophila gene required for Robo repulsion in epithelial cells and axons. Vilse defines a conserved family of RhoGAPs (Rho GTPase-activating proteins), with representatives in flies and vertebrates. The phenotypes of vilse mutants resemble the tracheal and axonal phenotypes of Slit and Robo mutants at the CNS midline. Dosage-sensitive genetic interactions between vilse, slit, and robo mutants suggest that vilse is a component of robo signaling. Moreover, overexpression of Vilse in the trachea of robo mutants ameliorates the phenotypes of robo, indicating that Vilse acts downstream of Robo to mediate midline repulsion. Vilse and its human homolog bind directly to the intracellular domains of the corresponding Robo receptors and promote the hydrolysis of RacGTP and, less efficiently, of Cdc42GTP. These results together with genetic interaction experiments with robo, vilse, and rac mutants suggest a mechanism whereby Robo repulsion is mediated by the localized inactivation of Rac through Vilse. 相似文献
39.
Ricardo Celestino Eva Sigstad Marthe Løvf Gard O. S. Thomassen Krystyna K. Grøholt Lars H. Jørgensen Aasmund Berner Patrícia Castro Ragnhild A. Lothe Trine Bjøro Manuel Sobrinho‐Simões Paula Soares Rolf I. Skotheim 《Genes, chromosomes & cancer》2012,51(12):1154-1164
Neoplasms frequently present structural chromosomal aberrations that can alter the level of expression of a protein or to the expression of an aberrant chimeric protein. In the thyroid, the PAX8‐PPARG fusion is present in the neoplastic lesions that have a follicular architecture—follicular thyroid carcinoma (FTC) and follicular variant of papillary thyroid carcinoma (FVPTC), and less frequently in follicular thyroid adenoma (FTA), while the presence of RET/PTC fusions are largely restricted to papillary thyroid carcinoma (PTC). The ability to detect fusion genes is relevant for a correct diagnosis and for therapy. We have developed a new fusion gene microarray‐based approach for simultaneous analysis of all known and predicted fusion gene variants. We did a comprehensive screen for 548 known and putative fusion genes in 27 samples of thyroid tumors and three positive controls—one thyroid cancer cell line (TPC‐1) and two PTCs with known CCDC6‐RET (alias RET/PTC1) fusion gene, using this microarray. Within the thyroid tumors tested, only well known, previously reported fusion genes in thyroid oncology were identified. Our results reinforce the pathogenic role played by RET/PTC1, RET/PTC3, and PAX8‐PPARG fusion genes in thyroid tumorigenesis. © 2012 Wiley Periodicals, Inc. 相似文献
40.
A novel IGF2/H19 domain triplication in the 11p15.5 imprinting region causing either Beckwith–Wiedemann or Silver–Russell syndrome in a single family 下载免费PDF全文