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961.
Nucleofection is an efficient nonviral transfection technique for human bone marrow-derived mesenchymal stem cells 总被引:5,自引:0,他引:5
Aluigi M Fogli M Curti A Isidori A Gruppioni E Chiodoni C Colombo MP Versura P D'Errico-Grigioni A Ferri E Baccarani M Lemoli RM 《Stem cells (Dayton, Ohio)》2006,24(2):454-461
Viral-based techniques are the most efficient systems to deliver DNA into stem cells because they show high gene transduction and transgene expression in many cellular models. However, the use of viral vectors has several disadvantages mainly involving safety risks. Conversely, nonviral methods are rather inefficient for most primary cells. The Nucleofector technology, a new nonviral electroporation-based gene transfer technique, has proved to be an efficient tool for transfecting hard-to-transfect cell lines and primary cells. However, little is known about the capacity of this technique to transfect adult stem cells. In this study, we applied the Nucleofector technology to engineer human bone marrow- derived mesenchymal stem cells (hMSCs). Using a green fluorescent protein reporter vector, we demonstrated a high transgene expression level using U-23 and C-17 pulsing programs: 73.7%+/-2.9% and 42.5%+/-3.4%, respectively. Cell recoveries and viabilities were 38.7%+/-2.9%, 44.5%+/-3.9% and 91.4%+/-1.3%, 94.31%+/-0.9% for U-23 and C-17, respectively. Overall, the transfection efficiencies were 27.4%+/-2.9% (U-23) and 16.6%+/-1.4% (C-17) compared with 3.6%+/-2.4% and 5.4%+/-3.4% of other nonviral transfection systems, such as FUGENE6 and DOTAP, respectively (p<.005 for all comparisons). Nucleofection did not affect the immunophenotype of hM-SCs, their normal differentiation potential, or ability to inhibit T-cell alloreactivity. Moreover, the interleukin-12 gene could be successfully transfected into hMSCs, and the immunomodulatory cytokine was produced in great amount for at least 3 weeks without impairment of its biological activity. In conclusion, nucleofection is an efficient nonviral transfection technique for hMSCs, which then may be used as cellular vehicles for the delivery of biological agents. 相似文献
962.
An EEG frequency band analysis was conducted, in order to explore the significance of brain oscillations (delta, theta, alpha and beta) for emotional face comprehension during different post-stimulus time intervals (50-150; 150-250; 250-350; and 350-450 ms). The study was conducted on twenty adults who looked at emotional (happy, sad, angry, fearful) or neutral faces. The results showed that motivational significance of the stimulus can modulate the power synchronization (event-related desynchronization (ERD) decrease) within the frequency band of delta and theta. We propose that delta and theta respond to variations in processing stage of emotional face: whereas, delta reflects updating of the stimulus, theta responds to the emotional significance of face. The findings revealed that emotional discrimination by theta is observable mainly within 150-250 time interval and that it is more distributed on anterior regions, whereas delta is maximally synchronized within 250-350 interval and more posteriorly distributed for all the stimulus type. Finally, a right-hemisphere dominance was found for theta during emotional face comprehension. 相似文献
963.
Endothelial nitric oxide synthase (Glu298Asp) polymorphism is an independent risk factor for migraine with aura 总被引:1,自引:0,他引:1
Borroni B Rao R Liberini P Venturelli E Cossandi M Archetti S Caimi L Padovani A 《Headache》2006,46(10):1575-1579
OBJECTIVE: The aim of the present study was to evaluate whether the functional endothelial nitric oxide synthase (eNOS) Glu298Asp polymorphism, which has been demonstrated to decrease the endothelial NOS activity, might be a risk factor for migraine. BACKGROUND: It has widely demonstrated that nitric oxide (NO) is involved in migraine pathogenesis. Several genetic risk factors have been associated with migraine, but no study has unraveled a possible relationship between migraine and eNOS Glu298Asp. Methods.-One hundred fifty-six migraine patients and 125 healthy nonheadache volunteers entered the study. Demographic and clinical characteristics were carefully recorded, and a neurological workup was performed. RESULTS: eNOS AspAsp homozygous patients had a 3-fold time risk for migraine with aura (MA) when compared to migraine without aura (MO) patients (OR-3.02, 95% CI-1.21 to 7.51), and more than 2-fold time increased risk when compared to control subjects (OR-2.21, 95% CI-1.00 to 5.04). In migraine patients, no difference in age at onset, mean attack's intensity, family history for any of the studied comorbidities, or the presence of comorbidities was found in eNOS AspAsp homozygous compared to eNOS GluGlu or eNOS GluAs carriers. CONCLUSIONS: Homozygous Asp298, a common variant of the eNOS gene, is an independent risk factor for MA in this study population. 相似文献
964.
Rainero I Ferrero M Rubino E Valfrè W Pellegrino M Arvat E Giordano R Ghigo E Limone P Pinessi L 《Headache》2006,46(4):597-603
OBJECTIVE: To evaluate the effects of analgesic overuse on endocrine function in patients with chronic migraine and medication-overuse headache (CM-MOH). BACKGROUND: Chronic migraine is frequently associated with an overuse of symptomatic medications. Drugs currently used in acute migraine attacks are associated with several endocrine effects. At present, the endocrine effects of medication overuse in chronic migraine patients are unknown. METHODS: Eighteen patients with CM-MOH, diagnosed according to the ICHD-II criteria, and 18 healthy controls received an intravenous administration of GHRH, hCRH, and TRH. Plasma concentrations of GH, TSH, ACTH, and cortisol were measured for a 90-minute period after administration of the specific releasing hormones. RESULTS: Hormonal basal concentrations were similar in both groups. GH response to GHRH was significantly reduced in patients with CM-MOH in comparison with controls. TRH induced a reduction of TSH concentrations only at the end of the test. After hCRH administration, ACTH and cortisol concentrations were significantly higher in cases than in controls. A significant correlation between duration of the disease and altered hormonal response was found. CONCLUSIONS: Our study shows that both corticotropic and somatotropic functions are significantly impaired in CM-MOH patients and suggests a role for hormones in the development of chronic migraine. 相似文献
965.
Functional validation of the anaplastic lymphoma kinase signature identifies CEBPB and BCL2A1 as critical target genes 总被引:2,自引:0,他引:2 下载免费PDF全文
966.
Porcellini S Traggiai E Schenk U Ferrera D Matteoli M Lanzavecchia A Michalak M Grassi F 《The Journal of experimental medicine》2006,203(2):461-471
Regulated expression of positive and negative regulatory factors controls the extent and duration of T cell adaptive immune response preserving the organism's integrity. Calreticulin (CRT) is a major Ca2+ buffering chaperone in the lumen of the endoplasmic reticulum. Here we investigated the impact of CRT deficiency on T cell function in immunodeficient mice reconstituted with fetal liver crt-/- hemopoietic progenitors. These chimeric mice displayed severe immunopathological traits, which correlated with a lower threshold of T cell receptor (TCR) activation and exaggerated peripheral T cell response to antigen with enhanced secretion of inflammatory cytokines. In crt-/- T cells TCR stimulation induced pulsatile cytosolic elevations of Ca2+ concentration and protracted accumulation of nuclear factor of activated T cells in the nucleus as well as sustained activation of the mitogen-activated protein kinase pathways. These observations support the hypothesis that CRT-dependent shaping of Ca2+ signaling critically contributes to the modulation of the T cell adaptive immune response. 相似文献
967.
Previous research has shown that in healthy individuals blood-related stimuli elicit a distinctive autonomic response pattern and heightened processing as compared with other unpleasant and arousing visual stimuli. In addition, growing evidence suggests that information processing of disorder-related stimuli is also different in blood phobia as compared with other specific phobias. In the present study, the magnitude of the startle eyeblink reflex elicited during the viewing of mutilation, human attack, erotica and neutral pictures was recorded in 22 blood phobics and 25 healthy controls. Startle eyeblink responses were measured at 300, 1500, 3500 and 4500-ms time intervals after picture onset in order to assess the attentional/affective modulation and its temporal course. Reliable startle inhibition to erotic pictures and startle potentiation to human attack scenes were found relative to neutral pictures. However, while both groups rated mutilations as the most unpleasant and arousing content, no blink facilitation relative to neutral contents was found at either early or late probe times. Crucially, such effect occurred independently of fear levels, as no difference between phobics and controls was found in the size of the startle blinks elicited throughout the viewing of blood pictures. 相似文献
968.
Hoare HL Sullivan LC Pietra G Clements CS Lee EJ Ely LK Beddoe T Falco M Kjer-Nielsen L Reid HH McCluskey J Moretta L Rossjohn J Brooks AG 《Nature immunology》2006,7(3):256-264
In contrast to antigen-specific immunity orchestrated by major histocompatibility complex (MHC) class Ia molecules, the ancestrally related nonclassical MHC class Ib molecules generally mediate innate immune responses. Here we have demonstrated the structural basis by which the MHC class Ib molecule HLA-E mediates an adaptive MHC-restricted cytotoxic T lymphocyte response to human cytomegalovirus. Highly constrained by host genetics, the response showed notable fine specificity for position 8 of the viral peptide, which is the sole discriminator of self versus nonself. Despite the evolutionary divergence of MHC class Ia and class Ib molecules, the structure of the T cell receptor-MHC class Ib complex was very similar to that of conventional T cell receptor-MHC class Ia complexes. These results emphasize the evolutionary 'ambiguity' of HLA-E, which not only interacts with innate immune receptors but also has the functional capacity to mediate virus-specific cytotoxic T lymphocyte responses during adaptive immunity. 相似文献
969.
Striano P Malacarne M Cavani S Pierluigi M Rinaldi R Cavaliere ML Rinaldi MM De Bernardo C Coppola A Pintaudi M Gaggero R Grammatico P Striano S Dallapiccola B Zara F Faravelli F 《American journal of medical genetics. Part A》2006,140(18):1944-1949
Mental retardation, facial dysmorphisms, seizures, and brain abnormalities are features of 6q terminal deletions. We have ascertained five patients with 6q subtelomere deletions (four de novo, one as a result of an unbalanced translocation) and determined the size of the deletion ranging from 3 to 13 Mb. Our patients showed a recognizable phenotype including mental retardation, characteristic facial appearance, and a distinctive clinico-neuroradiological picture. Focal epilepsy with consistent electroencephalographic features and with certain brain anomalies on neuroimaging studies should suggest 6q terminal deletion. The awareness of the distinctive clinical picture will help in the diagnosis of this chromosomal abnormality. 相似文献
970.
Mainardi PC Pastore G Castronovo C Godi M Guala A Tamiazzo S Provera S Pierluigi M Bricarelli FD 《European journal of medical genetics》2006,49(5):363-383
The aim of this report is to provide an update on the natural history of the Cri du Chat Syndrome by means of the Italian Register (I.R.). Two hundred twenty patients were diagnosed by standard cytogenetic methods and 112 of these were also characterised by molecular-cytogenetic investigation (FISH). FISH analysis showed interstitial deletions, short terminal deletions and other rare rearrangements not previously correctly diagnosed by standard cytogenetics. The diagnosis was made in the first month of life in 42% and within first year in 82% of cases. The remaining 18% were diagnosed at an age ranging from 13 months to 47 years. At the last follow-up, patient age ranged from 8 months to 61 years. Mortality, already low, has decreased over time as it is lower between 1984-2002 compared to 1965-1983. Mortality was higher in patients with unbalanced translocations resulting in 5p deletions. Our data confirm that the cat-like cry and peculiar timbre of voice are the most typical signs of the syndrome, not only at birth but also later and these are the only signs which might suggest the diagnosis in patients with small deletions and mild clinical picture. A cytogenetic and clinical variability must be underlined. Cardiac, cerebral, renal and gastrointestinal malformations were more frequent in the patients with unbalanced translocations resulting in 5p deletions. Sucking and feeding difficulties and respiratory infections are frequent in the first months or years of life. Intubation difficulties linked to larynx anomalies must be considered. Psychomotor development is delayed in all patients but there is a variability related to deletion size and type as well as other genetic and environmental factors. However, the results showed an improvement in the acquisition of the development skills and progress in social introduction which should encourage caregivers and parents to work together in carrying out the rehabilitative and educational interventions. 相似文献