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618 citation(s) found for "O'Brien, J F".

Elevation of cAMP in Mesenchymal Stem Cells Transiently Upregulates Neural Markers Rather than Inducing Neural Differentiation
Rooney, Gemma E., Howard, Linda , O’Brien, Timothy , Windebank, Anthony J. , Barry, Frank

Stem Cells and Development | June 13, 2008 | Volume: 18 | Issue: 3 | Pages: 387-398

10.1089/scd.2008.0080 | PMID 18554089 Get It

The aims of this research were to examine the neural expression profile of undifferentiated mesenchymal stem cells (MSCs), to define a serum-free environment that would support the survival of MSCs, and to assess the effects of elevated cyclic adenosine monophosphate (cAMP) levels on MSC morphology and expression of neural markers. The neural profile of MSCs was assessed using immunocytochemistry and real-time polymerase chain reaction (PCR) techniques. These MSCs were then cultured in varying serum-free environments, with flow cytometry analysis of cell viability and apoptosis. The effects of forskolin and 8 bromo-cAMP treatment on MSC morphology and expression of neural markers were assessed using light microscopy, immunocytochemistry and real-time PCR analysis. Expression of the neural markers nestin, vimentin, β III tubulin, glial fibrillary acidic protein, and the tropomyosin-related kinases was demonstrated in normal undifferentiated MSCs. Furthermore, MSCs cultured in serum-free conditions containing ascorbic acid 2-phosphate demonstrated greater long-term survival and reduced apoptosis. In contrast, forskolin increased the percentage of cells undergoing apoptosis. Culture in the presence of forskolin induced a 6-fold increase in β III tubulin expression after a 6-h exposure time, which was accompanied by dramatic changes in morphology. However, this effect was transient, with the cells reverting to their normal morphology by 24 h. Treatment with 8 bromo-cAMP induced similar increases in β III tubulin expression without such dramatic morphological changes. Factors which increase the concentration of cAMP induce transient changes in expression of neural markers that appear to be the result of cellular adaptation to changes in culture conditions rather than a real process of neural differentiation.
Three-Dimensional Ultrasound for Image-Guided Mapping and Intervention
Henz, Benhur Davi , Johnson, Susan B., Bunch, T. Jared , O'BRIEN, CHRISTINE J., Hodge, David O. , Altman, Andres, Govari, Assaf , Packer, Douglas L. , Okumura, Yasuo

Circulation: Arrhythmia and Electrophysiology | April 30, 2008 | Volume: 1 | Issue: 2 | Pages: 110-119

10.1161/circep.108.769935 | PMID 19808401 Get It

Background— Multiple factors create discrepancies between electroanatomic maps and merged, preacquired computed tomographic images used in guiding atrial fibrillation ablation. Therefore, a Carto-based 3D ultrasound image system (Biosense Webster Inc) was validated in an animal model and tested in 15 atrial fibrillation patients. Methods and Results— Twelve dogs underwent evaluation using a newly developed Carto-based 3D ultrasound system. After fiducial clip markers were percutaneously implanted at critical locations in each cardiac chamber, 3D ultrasound geometries, derived from a family of 2D intracardiac echocardiographic images, were constructed. Point-source error of 3D ultrasound-derived geometries, assessed by actual real-time 2D intracardiac echocardiographic clip sites, was 2.1�1.1 mm for atrial and 2.4�1.2 mm for ventricular sites. These errors were significantly less than the variance on CartoMerge computed tomographic images (atria: 3.3�1.6 mm; ventricles: 4.8�2.0 mm; P< 0.001 for both). Target ablation at each clip, guided only by 3D ultrasound-derived geometry, resulted in lesions within 1.1�1.1 mm of the actual clips. Pulmonary vein ablation guided by 3D ultrasound-derived geometry resulted in circumferential ablative lesions. Mapping in 15 patients produced modestly smaller 3D ultrasound versus electroanatomic map left atrial volumes (98�24 cm 3 versus 109�25 cm 3 , P< 0.05). Three-dimensional ultrasound-guided pulmonary vein isolation and linear ablation in these patients were successfully performed with confirmation of pulmonary vein entrance/exit block. Conclusions— These data demonstrate that 3D ultrasound images seamlessly yield anatomically accurate chamber geometries. Image volumes from the ultrasound system are more accurate than possible with CartoMerge computed tomographic imaging. This clinical study also demonstrates the initial feasibility of this guidance system for ablation in patients with atrial fibrillation.
Gene-Modified Mesenchymal Stem Cells Express Functionally Active Nerve Growth Factor on an Engineered Poly Lactic Glycolic Acid (PLGA) Substrate
Rooney, Gemma E., Moran, Cathal J., McMahon, Siobhán S. , Ritter, Thomas , Maenz, Martin, Flügel, Alexander , Dockery, Peter , O’Brien, Timothy , Howard, Linda , Windebank, Anthony J. , Barry, Frank

Tissue Engineering Part A | April 11, 2008 | Volume: 14 | Issue: 5 | Pages: 681-690

10.1089/tea.2007.0260 | PMID 18402551 Get It

Subtraction ictal single-photon emission computed tomography coregistered to magnetic resonance imaging in evaluating the need for repeated epilepsy surgery
Wetjen, Nicholas M. , Cascino, Gregory D. , Fessler, A. James, So, Elson L., Buchhalter, Jeffrey , Mullan, Brian P., O’Brien, Terence J. , Meyer, Fredric B. , Marsh, W. Richard

Journal of Neurosurgery | January 24, 2008 | Volume: 105 | Issue: 1 | Pages: 71-76

10.3171/jns.2006.105.1.71 | PMID 16874891 Get It

Object The aim of this study was to determine whether ictal single-photon emission computed tomography (SPECT) is useful in localizing the site of seizure onset in patients in whom surgery for intractable epilepsy failed and who are being considered for repeated surgery. Methods Subtraction ictal SPECT coregistered to magnetic resonance imaging (SISCOM) studies were retrospectively analyzed in 58 patients who were being evaluated for possible repeated resection for intractable partial epilepsy between January 1, 1996, and October 31, 1999. All patients had persistent seizures subsequent to an initial resection and underwent another excision. The SISCOM-demonstrated abnormalities were classified as concordant, discordant, or indeterminate, compared with the localization of the epileptogenic zone revealed on video electroencephalography monitoring. The ability of SISCOM to predict operative outcome was also determined in patients who had undergone repeated surgical procedures. The SISCOM studies revealed a localized hyperperfused alteration in 46 (79%) of 58 patients. Forty-one (89%) of these 46 patients had a SISCOM-demonstrated alteration in the hemisphere of the previous epilepsy surgery. Imaging changes in 33 (72%) of the 46 patients were at the site of the previous focal cortical resection. Eight (17%) of the 46 had SISCOM-demonstrated abnormalities remote from the lobe in which surgery had been performed but in the ipsilateral hemisphere. The hyperperfusion focus was in the contralateral hemisphere in the remaining five patients (11%). The site of the epileptogenic zone was concordant with the SISCOM focus in 32 (70%) of 46 patients. Twenty-six patients underwent repeated resection and were followed up for a mean of 44 months thereafter; 11 of these patients (42%) had a significant reduction in seizure tendency. Only five patients (19%) were seizure free. Ten (50%) of 20 patients with a concordant SISCOM focus compared with none (0%) of three patients with a discordant focus had a favorable surgical outcome (p = 0.23). Conclusions The SISCOM method might be useful in the evaluation of, and the surgical planning for, patients with intractable partial epilepsy in whom previous resective treatment has failed and who are being considered for reoperation.
Mayo Clinic Risk Score for Percutaneous Coronary Intervention Predicts In-Hospital Mortality in Patients Undergoing Coronary Artery Bypass Graft Surgery
Li, Shuang , Rumsfeld, John S., Spertus, John A. , O’Brien, Sean M. , Suri, Rakesh M. , Singh, Mandeep , Gersh, Bernard J. , Peterson, Eric D. , Spertus, John A

Circulation | January 3, 2008 | Volume: 117 | Issue: 3 | Pages: 356-362

10.1161/circulationaha.107.711523 | PMID 18172033 Get It

Background— Current risk models predict in-hospital mortality after either coronary artery bypass graft surgery or percutaneous coronary interventions separately, yet the overlap suggests that the same variables can define the risks of alternative coronary reperfusion therapies. Our goal was to seek a preprocedure risk model that can predict in-hospital mortality after either percutaneous coronary intervention or coronary artery bypass graft surgery. Methods and Results— We tested the ability of the recently validated, integer-based Mayo Clinic Risk Score (MCRS) for percutaneous coronary intervention, which is based solely on preprocedure variables (age, creatinine, ejection fraction, myocardial infarction ≤24 hours, shock, congestive heart failure, and peripheral vascular disease), to predict in-hospital mortality among 370 793 patients in the Society of Thoracic Surgeons database undergoing isolated coronary artery bypass graft surgery from 2004 to 2006. For the Society of Thoracic Surgeons coronary artery bypass graft surgery population studied, the median age was 66 years (quartiles 1 to 3, 57 to 74 years), with 37.2% of patients ≥70 years old. A high prevalence of comorbid conditions, including diabetes mellitus (37.1%), hypertension (80.5%), peripheral vascular disease (15.3%), and renal disease (creatinine ≥1.4 mg/dL; 11.8%), was present. A strong association existed between the MCRS and the observed mortality in the Society of Thoracic Surgeons database. The in-hospital mortality ranged between 0.3% (95% confidence interval 0.3% to 0.4%) with a score of 0 on the MCRS and 33.8% (95% confidence interval 27.3% to 40.3%) with an MCRS score of 20 to 24. The discriminatory ability of the MCRS was moderate, as measured by the area under the receiver operating characteristic curve (C-statistic=0.715 to 0.784 among various subgroups); performance was inferior to the Society of Thoracic Surgeons model for most categories tested. Conclusions— This model, which is based on 7 preprocedure risk variables, may be useful for providing patients with individualized, evidence-based estimates of procedural risk as part of the informed consent process before percutaneous or surgical revascularization.
Screening for Biotinidase Deficiency in Children with Unexplained Neurologic or Developmental Abnormalities
Sutherland, Steven J., Olsen, Richard D., Michels, Virginia V., Schmidt, Michael A. , O’Brien, John F.

Clinical Pediatrics | November 26, 2007 | Volume: 30 | Issue: 2 | Pages: 81-84

10.1177/000992289103000203 | PMID 1706649 Get It

To test the hypothesis that the frequency of biotinidase deficiency is greater in children with unexplained developmental delay or neurologic abnormalities than in the general population, we studied children seen at a large outpatient clinic over a four-year period who had one or more of these neurologic abnormalities and for whom no specific cause for their abnormalities could be found. The group totaled 274 children (163 boys; 111 girls) whose ages ranged from 2 weeks to 17 years. Characteristics were IQ/DQ, 30 to 70 in the 115 for whom scores were available; 41% had seizures; 15% had sensorineural hearing loss; 54% showed gross motor delay or ataxia; and 27% had decreased muscle tone. One patient with a classical clinical picture of biotinidase deficiency was diagnosed during the study period and was not included in the study. None of the patients with nonclassic findings had a deficiency of biotinidase activity. Our results suggest that biotinidase deficiency does not account for a large proportion of children with unexplained neurologic abnormalities or developmental delay. This does not negate the importance of biotinidase testing in children with clinical patterns specifically suggestive of the deficiency.
Atrophy rates accelerate in amnestic mild cognitive impairment
Jack, Clifford R. , Weigand, Stephen D. , Shiung, Maria M., Przybelski, Scott A. , O’Brien, Peter C. , Gunter, Jeffrey L. , Smith, Glenn E. , Petersen, Ronald C. , Knopman, David S. , Boeve, Bradley F. , Jack, Clifford R

Neurology | November 22, 2007 | Volume: 70 | Issue: 19_part_2 | Pages: 1740-1752

10.1212/01.wnl.0000281688.77598.35 | PMID 18032747 Get It

Feasibility of an Affected Sibling Pair Study in Ischemic Stroke
Brown, Robert D., Brott, Thomas G. , Hardy, John , Atkinson, Elizabeth J. , O’Brien, Peter C. , Meschia, James F. , Hardy, John

Stroke | October 10, 2007 | Volume: 32 | Issue: 12 | Pages: 2939-2941

10.1161/hs1201.099795 | PMID 11739999 Get It

Background and Purpose — We sought to determine pedigree availability for a concordant sibling pair study of genetic risk factors in ischemic stroke. Methods — Probands with confirmed ischemic stroke were prospectively enrolled. Family histories were obtained by systematic interview. A study neurologist prospectively assigned stroke subtype. Results — Of 310 probands (median age, 75 years; range, 26 to 97 years; 48% women), 75% had at least 1 living sibling; 10%, at least 1 concordant living sibling; 2%, at least 1 concordant sibling living in the same city; and 7%, at least 1 concordant living and 1 discordant living sibling. Likelihood of having a concordant sibling increased significantly with proband age, even after adjustment for sibship size ( P =0.002). Positive family history of stroke was not related to either proband stroke subtype or risk factor profile. Conclusions — Approximately 10 probands were screened to find 1 potentially concordant living sibling. A concordant sibling pair study should be multicentered and enable enrollment of siblings from diverse geographic areas.
Challenges in Design of Multicenter Trials
Dyck, P. James B. , Norell, Jane E., Tritschler, Hans, Schuette, Klemens, Самигуллин, Р. Р., Bastyr, Edward J., Litchy, William J. , O’Brien, Peter C. , Ziegler, Dan

Diabetes Care | September 28, 2007 | Volume: 30 | Issue: 10 | Pages: 2619-2625

10.2337/dc06-2479 | PMID 17513707 Get It

OBJECTIVE—Assessing clinimetric performance of diabetic sensorimotor polyneuropathy (DSPN) end points in single and multicenter trials. RESEARCH DESIGN AND METHODS—Assessed were placebo-treated patients with DSPN in the Viatris and Eli Lilly trials and an epidemiologic cohort. RESULTS—Test reproducibility in clinical trial cohorts (rI ∼ 0.7–0.85) approached that in the epidemiologic cohort (rI ∼ 0.85–0.95). Associations between pairs of end points explained &lt;10% of the variability of data (sometimes 15–35%), being higher in the epidemiologic cohort and the Viatris trial than in the Lilly trial. Most end points did not show monotonic worsening over 4 years. However, sural nerve amplitude and peroneal motor conduction velocity did. A nerve conduction score (Σ 5 NC nds [5 attributes of nerve conduction expressed as normal deviates]) did not show monotonic worsening in established DSPN. In the epidemiologic cohort followed for 9.5 years, monotonic worsening of small magnitude occurred for sural amplitude, vibration detection threshold, and especially for composite quantitative sensation. CONCLUSIONS—The main reason why it is difficult to demonstrate monotonic worsening of neuropathic end points appears to be a very slow worsening of DSPN, a placebo effect for symptoms and signs, and measurement noise. Demonstrating disease progression in controlled trials of DSPN is more likely when 1) patients with developing rather than established DSPN are selected, 2) type 1 diabetic patients are preferentially recruited, 3) patients are selected who cannot or will not achieve ideal glycemic control, 4) end points chosen are known to show monotonic worsening, and 5) a restricted number of centers and expert examiners (trained, certified, using standard approaches, and reference values and interactive surveillance of tests) are used.
Nilotinib (formerly AMN107), a highly selective BCR-ABL tyrosine kinase inhibitor, is effective in patients with Philadelphia chromosome–positive chronic myelogenous leukemia in chronic phase following imatinib resistance and intolerance
Kantarjian, Hagop M. , Gattermann, Norbert , Bhalla, Kapil N. , Alimena, Giuliana, Palandri, Francesca , Ossenkoppele, Gert J., Nicolini, Franck-Emmanuel, O’Brien, Stephen G., Litzow, Mark R. , Cervantes, Francisco , Shou, Yaping, Resta, Debra, Weitzman, Aaron, Hochhaus, Andreas , Coutre, Philipp le , Giles, Francis Joseph , Bhatia, Ravi , Haque, Md Ariful , Palandri, Francesca , Kantarjian, Hagop

Blood | August 22, 2007 | Volume: 110 | Issue: 10 | Pages: 3540-3546

10.1182/blood-2007-03-080689 | PMID 17715389 Get It

Abstract Nilotinib, an orally bioavailable, selective Bcr-Abl tyrosine kinase inhibitor, is 30-fold more potent than imatinib in pre-clinical models, and overcomes most imatinib resistant BCR-ABL mutations. In this phase 2 open-label study, 400 mg nilotinib was administered orally twice daily to 280 patients with Philadelphia chromosome–positive (Ph+) chronic myeloid leukemia in chronic phase (CML-CP) after imatinib failure or intolerance. Patients had at least 6 months of follow-up and were evaluated for hematologic and cytogenetic responses, as well as for safety and overall survival. At 6 months, the rate of major cytogenetic response (Ph ≤ 35%) was 48%: complete (Ph = 0%) in 31%, and partial (Ph = 1%-35%) in 16%. The estimated survival at 12 months was 95%. Nilotinib was effective in patients harboring BCR-ABL mutations associated with imatinib resistance (except T315I), and also in patients with a resistance mechanism independent of BCR-ABL mutations. Adverse events were mostly mild to moderate, and there was minimal cross-intolerance with imatinib. Grades 3 to 4 neutropenia and thrombocytopenia were observed in 29% of patients; pleural or pericardial effusions were observed in 1% (none were severe). In summary, nilotinib is highly active and safe in patients with CML-CP after imatinib failure or intolerance. This clinical trial is registered at http://clinicaltrials.gov as ID no. NCT00109707.