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971.
Chapman H Pierno AC Cunnington R Gavrilescu M Egan G Castiello U 《Neuroscience letters》2007,417(2):171-175
The selection of objects in the visual environment is important in everyday life when acting in a goal-directed manner. Here we used functional magnetic resonance imaging (fMRI) to investigate brain activity while healthy subjects (N=15) selectively reached to grasp a three-dimensional (3D) target stimulus presented either in isolation or in the presence of 3D non-target stimuli. A pneumatic MRI compatible apparatus was designed to precisely control the presentation of 3D graspable stimuli within the scanner. During scanning subjects were instructed to reach and grasp towards a target presented at an unknown location either in isolation or flanked by two distractor objects. Results indicated that reaching towards and grasping the target object in the presence of other non-target stimuli was associated with greater activation within the contralateral primary motor cortex and the precuneus as compared to the execution of reach-to-grasp movements towards the target presented in isolation. We conclude that the presence of non-targets evokes a differential level of neural activity within areas responsible for the planning and execution of selective reach-to-grasp movement. 相似文献
972.
The effects of cyclic AMP-related compounds and beta adrenoceptor agonists on the basal and lipopolysaccharide (LPS)-stimulated
release of endothelin-1 (ET-1) from guinea-pig tracheal epithelial cells (GPTEpCs) in culture were studied. Forskolin (a potent
activator of adenylyl cyclase), 8-bromo-cyclic AMP (a cyclic AMP analogue), salbutamol and salmeterol (two beta 2-adrenoceptor
agonists), were used to increase cyclic AMP levels. Cultured GPTEpCs released ET-1 continuously over a 24 h incubation period.
The values reached 1,938 ± 122 pg/mg of total cell proteins after 24 h. LPS (10 μg/ml) significantly stimulated the release
of ET-1 by 1.6- to 1.8-fold, up to 1,262 ± 56 pg/mg total cell proteins after an 8 h incubation period. Compound 8-bromo-cyclic
AMP (10−5, 10−4 and 10−3 M) reduced the basal release of ET-1 from GPTEpCs by up to 31% (P < 0.01) and the LPS stimulated release by up to 42% (P < 0.05), after an 8 h incubation period. Forskolin (10−6, 10−5 and 10−4 M) also inhibited the basal release of ET-1 by up to 28% (P < 0.05) and LPS-stimulated release of ET-1 by up to 50% (P < 0.05), after an 8 h incubation period. At the concentration of 10−5 M, forskolin increased cyclic AMP levels in GPTEpCs by 17-fold (P < 0.001) in the medium, 15 min after the beginning of the incubation. Salbutamol (10−8 to 10−6 M) had no effect on the basal production and release of ET-1 after 8 h. Conversely, this short acting beta 2-adrenoceptor
agonist significantly reduced LPS-mediated increase of ET-1 production by up to 55% (P < 0.05) after an 8 h incubation period. Salmeterol (10−9 M to 10−5 M) inhibited basal and LPS-stimulated production and release of ET-1 after an 8 h incubation period (between 44 and 51%,
P < 0.01). Both salbutamol and salmeterol (10−6 M) increase cyclic AMP levels by five- and twofold, respectively (P < 0.05). In summary, these observations indicate that beta 2-adrenoceptor agonists or cyclic AMP enhancers can modulate both
basal and more markedly, the enhanced production of ET-1 from LPS-activated guinea pig airway EpCs. In addition, these compounds
increase cyclic AMP levels in the cells. It is suggested that there is a correlation between cyclic AMP increase and inhibition
of ET-1 release by guinea pig airway EpCs. Since ET-1 production was shown to be elevated in asthmatic subjects and in patients
suffering from other inflammatory lung disorders, the inhibition of its production by beta adrenoceptor agonists, such as
salbutamol and salmeterol, could be added to their therapeutical benefits. 相似文献
973.
Mievis S Levivier M Vassart G Brotchi J Ledent C Blum D 《Neurobiology of aging》2007,28(12):1944-1946
We have evaluated the neuroprotective effects of citicoline in relevant phenotypic models of Huntington's disease induced by either the mitochondrial inhibitor 3-nitropropionic acid or the N-methyl-d-aspartate agonist quinolinic acid, which, respectively, reproduce the metabolic defect or the excitotoxicity seen in the disease. We found that citicoline failed to reverse behavioural and histological alterations induced by both neurotoxins. In addition, citicoline did not reduce PC12 cell death induced by the expression of an N-terminal fragment of mutated Huntingtin. Altogether, our results suggest that citicoline is not a potential therapeutic agent for the treatment of Huntington's disease. 相似文献
974.
Tveito S Maelandsmo GM Hoifodt HK Rasmussen H Fodstad O 《Clinical & experimental metastasis》2007,24(5):317-327
Molecular studies of rare cells, such as circulating cancer cells, require efficient pre-enrichment steps to obtain a pure
population of target cells for further characterization. We have developed a two-step approach, starting with immunomagnetic
enrichment, followed by specific isolation of individual, easily identifiable bead-rosetted target cells using a new semi-automated
CellPick system. With this procedure, 1–50 live target cells can now be isolated. As a model system, we spiked a small number
of tumor cells into millions of normal mononuclear cells (MNCs). Efficient isolation of pure target cells was obtained by
use of the CellPick system, and the nature of isolated, bead-rosetted cells was verified by use of FISH. Single breast cancer
cells were picked directly into an RNA preserving lysis buffer, reverse transcribed, and PCR amplified with two cDNA specific
primer sets. With the isolated cells we consistently obtained both ubiquitously expressed and tumor cell specific PCR products.
We also performed a successful mutation analysis of single cells using PCR and cycling temperature capillary electrophoresis
(CTCE). This may have significant clinical implications in cancer and in other diseases, e.g. in characterizing micrometastatic
cancer cells in blood and lymph nodes to help identifying patients who most likely will respond to therapies like tyrosine
kinase inhibitors and compounds targeting specific mutations. By use of the CellPick system it is possible to specifically
isolate bead-rosetted or otherwise labelled target cells from a heterogeneous cell population for further molecular characterization. 相似文献
975.
Borkenhagen A Brähler E Wisch S Stöbel-Richter Y Strauss B Kentenich H 《Human reproduction (Oxford, England)》2007,22(7):2051-2057
BACKGROUND: In Germany, preimplantation genetic diagnosis (PGD) is currently not legal, but there is still a controversial debate about legalization. Studies about the attitudes of infertile couples towards PGD are rare. METHODS: A survey was conducted with 265 German infertile couples about knowledge, attitudes and prospective use of PGD. The influence of independent variables associated with approval of PGD is analysed by binary logistic regression. RESULTS: Sixty percent of respondents have heard about PGD. Eighty-seven percent support a general legalization of PGD in Germany for severe, early-onset genetic diseases. Seventy-four percent consider PGD morally acceptable. Sixty percent supported legalizing PGD for HLA-matching. But only a minority approved PGD to test for non-health-related traits. Respondents with a higher education level were the least supportive to all uses of PGD. CONCLUSIONS: Our results suggest that German infertile couples are as liberal towards PGD for health-related uses as in other western countries. They would legalize and use PGD to raise the rates to get pregnant and to avoid severe diseases of the offspring. Taking the opinions of German infertile couples into consideration could help redefine and reframe the public debate towards legalization of PGD and the moral status of the embryo in Germany. 相似文献
976.
MacLachlan NJ Zientara S Stallknecht DE Boone JD Goekjian VH Sailleau C Balasuriya UB 《Virus research》2007,129(2):236-240
The sequences of the S10 genes of 28 recent isolates (1994-2004) of bluetongue virus (BTV) from the United States (US) and French Martinique Island (2006) in the Caribbean Basin were compared in phylogenetic analyses to those of viruses previously isolated in the same regions. Although the analyses segregated the recent virus isolates from the two regions into distinct topotype clusters, the analyses also confirm that viruses from the US and the Caribbean Basin/Central America can share similar S10 genes despite the fact that distinct constellations of BTV serotypes occur in the two regions. 相似文献
977.
Stübgen JP 《Electromyography and clinical neurophysiology》2007,47(1):55-60
BACKGROUND: Quantitative electromyography (EMG) using different needle techniques was performed as part of a complete systems review on 9 patients diagnosed with the vacuolar variant of rigid spine syndrome (RSS). Purpose: To establish statistically: (1) correlations between clinical features (patient age, disease duration, degree of weakness) and quantitative EMG; (2) correlation between different EMG parameters; (3) differences in quantitative EMG comparing patients with a healthy control group; and (4) correlate EMG with muscle pathology findings. METHODS: Nerve conduction studies and needle EMG (motorunit analysis, MacroEMG, SFEMG) were performed on Mm. triceps brachii and tibialis anterior according to standard techniques on 9 RSS patients. RESULTS: Nerve conduction studies were normal. Overall, clinical parameters did not correlate well with motorunit analysis and MacroEMG results. Motorunit analysis and MacroEMG results were significantly different comparing patients with controls. Motorunit analysis and MacroEMG correlated well with muscle biopsy findings. SFEMG results were within normal limits. CONCLUSION: Comprehensive EMG study results were compatible with a benign myopathic process. Results were consistent amongst patients within the study group, but differed significantly from the control group. Stable neuromuscular junction physiology did not accurately reflect evidence of muscle fiber degeneration and regeneration observed on muscle biopsies. 相似文献
978.
Stübgen JP 《Electromyography and clinical neurophysiology》2007,47(4-5):233-241
BACKGROUND: Clinical or subclinical abnormalities of the central nervous system (CNS) have been reported in a range of primary muscle diseases, including the muscular dystrophies. PURPOSE: To ascertain by neurophysiologic techniques evidence of CNS dysfunction in a relatively large, homogeneous group of patients with facioscapulohumeral muscular dystrophy (FSHD). METHODS: Standard evoked potential (EP) and electroretinogram techniques were used to study the visual, auditory and somatosensory pathways in 20 patients with FSHD. RESULTS: Abnormal values were recorded in 70% (14/20) of patients, specifically of visual pathways (4/20), brainstem auditory pathways (4/20), median (5/20) and tibial nerve (2/20) somatosensory pathways, and of the retina (2/18). Abnormal results did not correlate with clinical parameters of patient age, disease duration and degree of weakness. CONCLUSIONS: Any process that caused CNS conduction delays was tentatively associated with FSHD. Sensorineural hearing deficit and vascular retinopathy were rare causes of abnormal EPs. Peripheral conduction delay of the arms was ascribed to mechanical factors secondary to shoulder girdle weakness. Progress in genetics and molecular pathogenesis of FSHD may shed further insight into the association between the myodystrophic process and nervous system abnormalities. 相似文献
979.
Nucleic acid extraction and human immunodeficiency virus type 1 (HIV-1) genotyping using the NucliSens miniMAG platform and the TruGene HIV-1 genotyping kit gave HIV-1 sequence data from HIV-1-negative plasma spiked with 100 copies/ml reference HIV-1 RNA and from low-viremia clinical samples (<500 copies/ml) without the need for ultracentrifugation or nested second-round PCR. 相似文献
980.
Human lymphocytes derived from the blood of a donor immunized with anthrax vaccine were isolated and enriched for B-cells by Nycoprep density centrifugation. Individual anti-anthrax protective antigen (PA) B-cells were isolated by fluorescence activated cell sorting with fluorescence-labeled recombinant PA (rPA). The RNA from sorted single B-cells was extracted using plant total RNA as the carrier prior to purification by Nanoprep RNA isolation columns and then cDNA was prepared. Donor specific human Fab primer sets were developed based on rapid amplification of 5'-complementary DNA end results. Heavy chain and light chain of human Fab were amplified from the donor single B-cells by PCR. The amplified heavy and light chain were then cloned into the expression vector pASK-IBA2 and expressed in Escherichia coli (E. coli). The chains combined in vivo to form a functional Fab which was then purified as one protein. The human Fab antibodies produced by this technique were functional when tested in Western blots where the rPA was the target as well as in ELISA. This approach allowed us to obtain human Fab that retained the natural heavy and light chain pairing, which is supposed to have a high antigen-binding affinity. 相似文献