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R Schneider

Publications and source records attributed to R Schneider.

At least 19 recordsLinked to original sources
PubMed2007

Massive hemoptysis in an 11-year-old girl with isolated pulmonary arteritis.

A 10-year-old girl developed recurrent bouts of massive hemoptysis over a 9-month period. No obvious bleeding source was detected. Her pulmonary angiogram showed a pulmonary aneurysm of the second branch of the left main pulmonary artery as well as widespread irregularities of the pulmonary arteries including areas of stenosis and pruning. Elective embolization of the aneurysm did not control hemoptysis and emergency left upper lobectomy had to be performed. Histology showed large artery wall injury with acute leucocytoclastic inflammation, fibrinoid necrosis, granulomatous inflammation, and ectasia of vessel wall. This combination of abnormalities has not been described to date and represents the first case of isolated pulmonary arteritis in children prior to puberty.

Aneurysm↗
PubMed2007

Cognitive plasticity in people at risk for dementia: optimising the testing-the-limits-approach.

A topic of great interest in gerontology research is the prediction of cognitive deterioration which marks the transition from mild cognitive impairment (MCI) to dementia. In this area, the term cognitive plasticity can be of great interest. We examined the utility of the Adaptive Figure Series Learning Test (ADAFI) to evoke cognitive plasticity and to show whether reduced plasticity can be found in people with MCI. In a pre-test-intervention-post-test design, intervention with the ADAFI was compared to an unspecific brain jogging task in MCI participants and healthy controls. A total of 42 subjects were included. Independent of mental health status only using the ADAFI led to pronounced improvements in post-test performances, but MCI participants profited less from the intervention with the ADAFI than healthy controls, that is, showed lower cognitive plasticity. Thus, the overlap in performance distributions between healthy participants and MCI individuals at pre-test was reduced at the time of post-test once the ADAFI had been given as intervention. The findings of the present article indicate that plasticity oriented information can be gained when the ADAFI is given as an intervention in a pre-test-training-post-test-design. The cognitive plasticity approach seems potentially useful for purposes of early identification of dementia.

Aged↗
PubMed2006

Tumour necrosis factor alpha inhibitors in the treatment of childhood uveitis.

OBJECTIVE: To describe the efficacy of anti-TNF-alpha agents in the treatment of childhood uveitis. METHODS: We performed a retrospective chart review of all children with uveitis treated with TNF-alpha blockers at The Hospital for Sick Children, Toronto. RESULTS: Twenty-one children with uveitis were treated with the anti-TNF-alpha agents etanercept (11 patients) and infliximab (13 patients), resulting in 24 treatment courses. All patients had persistently active uveitis despite treatment with at least one standard immunosuppressive drug before the start of anti-TNF-alpha therapy. Six of 21 patients (29%) had idiopathic uveitis. In the other 15 patients, the underlying disease was juvenile idiopathic arthritis in 12 (57%), Behçet disease in two (9%) and sarcoidosis in one (5%). Response to etanercept treatment was good in 27%, moderate in 27% and poor in 45% of patients. Response to infliximab treatment was good in 38%, moderate in 54% and poor in 8% of patients. The difference in the percentage of patients with a moderate or good response was statistically significant (P = 0.0481). We also observed a lower rate of complications, such as new-onset or worsening glaucoma or cataract in the infliximab-treated group. CONCLUSION: Anti-TNF-alpha treatment was beneficial in a high percentage of patients with childhood uveitis refractory to standard immunosuppressive treatment. Infliximab resulted in better clinical responses with less ocular complications than etanercept.

Adolescent↗
PubMed2006

Predictors of disease course and remission in systemic juvenile idiopathic arthritis: significance of early clinical and laboratory features.

OBJECTIVE: To determine whether the disease course in systemic juvenile idiopathic arthritis (JIA) can be characterized as monophasic, polycyclic, or persistent, and to determine whether early clinical and laboratory characteristics can be used to predict the disease course and time to remission. METHODS: Forty-five children with systemic JIA diagnosed between 1996 and 2000 were followed up with a standardized data collection protocol, including data on clinical and laboratory features (mean followup 4.9 years). Disease was considered inactive if the clinical and laboratory features were normal. Three definitions of remission were applied to classify disease course. Predictors of disease course were evaluated using multiple logistic regression. Predictors of time to remission were evaluated using Cox proportional hazards regression. RESULTS: When applying a definition of remission requiring inactive disease while not receiving any medications for a period of 3 months, 42.2%, 6.7%, and 51.1% of the patients were classified as having monophasic, polycyclic, and persistent disease, respectively. Fever and active arthritis at 3 months (R2 = 0.42, area under the receiver operating characteristics curve [AUC] = 0.76) and an erythrocyte sedimentation rate (ESR) >26 mm/hour and corticosteroid use at 6 months (R2 = 0.49, AUC = 0.92) were predictive of a nonmonophasic course. Absence of active arthritis, an ESR of <26 mm/hour, and no requirement for corticosteroid therapy at 3 and 6 months were predictors of an earlier time to remission. CONCLUSION: The disease course in systemic JIA can be characterized as monophasic, polycyclic, or persistent using a definition of remission requiring 3 months of inactive disease while not receiving any therapy. Features at 3 and 6 months are predictive of the disease course and time to remission.

Adolescent↗
PubMed2006

Risk of new-onset uveitis in patients with juvenile idiopathic arthritis treated with anti-TNFalpha agents.

OBJECTIVE: To determine whether treatment with tumor necrosis factor alpha (TNFalpha)-blocking agents alters the incidence of new-onset uveitis in patients with juvenile idiopathic arthritis (JIA). STUDY DESIGN: Cohort study based on retrospective chart review. The charts of all 1109 patients with a diagnosis of JIA seen between January 1, 1996, and June 30, 2003, at our clinic were reviewed for diagnosis of uveitis and treatment with TNFalpha inhibitors. Cox regression analysis was performed with anti-TNFalpha treatment as a time-dependent covariate for risk of development of uveitis. RESULTS: We identified 70 patients treated with anti-TNFalpha without a prior diagnosis of uveitis. Two of these 70 patients (2.9%), both treated with etanercept, had development of new-onset uveitis during anti-TNFalpha therapy. One had juvenile psoriatic arthritis diagnosed 4.1 years before onset of uveitis. The other had extended oligoarticular JIA diagnosed 6.4 years before onset of uveitis. We found no statistically significant difference in the risk for development of uveitis between patients with or without anti-TNFalpha treatment. CONCLUSIONS: In our patients with JIA, anti-TNFalpha treatment did not alter the risk for development of new-onset uveitis. However, anti-TNFalpha therapy with etanercept did not prevent the development of uveitis in 2 patients.

Adolescent↗
PubMed2006

EELS investigations of different niobium oxide phases.

Electron energy loss spectra in conjunction with near-edge fine structures of purely stoichiometric niobium monoxide (NbO) and niobium pentoxide (Nb2O5) reference materials were recorded. The structures of the niobium oxide reference materials were checked by selected area electron diffraction to ensure a proper assignment of the fine structures. NbO and Nb2O5 show clearly different energy loss near-edge fine structures of the Nb-M4,5 and -M2,3 edges and of the O-K edge, reflecting the specific local environments of the ionized atoms. To distinguish the two oxides in a quantitative manner, the intensities under the Nb-M4,5 as well as Nb-M2,3 edges and the O-K edge were measured and their ratios calculated. k-factors were also derived from these measurements.

Journal Article↗
PubMed2005

Developing a disease activity tool for systemic-onset juvenile idiopathic arthritis by international consensus using the Delphi approach.

OBJECTIVES: The systemic form of juvenile idiopathic arthritis may present with many diverse symptoms, signs and laboratory abnormalities. Our aim was to elicit and pool items useful for developing a consensus disease activity measure for systemic arthritis in children, using an international pool of respondents. METHODS: We used a Delphi survey process in two steps. First we surveyed 187 paediatric rheumatologists and allied health professionals. We elicited 2607 items that, when combined with previously elicited items from parents/patients, could be pooled into 107 independent items. We then surveyed the paediatric rheumatologists to determine the frequency and importance of the 107 items. RESULTS: Our response rate was 83% to both surveys. We identified 29 items as being the most important and most frequently seen indicators of active disease. The most highly rated of these items were: presence of fever, presence of rash, elevated ESR, elevated CRP, requirement for increasing medications, abnormal physician global evaluation and presence of joints with active arthritis. CONCLUSIONS: Twenty-nine items are thought by medical practitioners to be most relevant in determining disease activity in systemic arthritis. As a next step, the measurement properties of these items will be tested to help develop a disease activity tool.

Algorithms↗
PubMed2005

Observation of interband pairing interaction in a two-band superconductor: MgB2.

The recently discovered anisotropic superconductor MgB2 is the first of its kind showing the intriguing properties of two-band superconductivity. By tunneling experiments using thin film tunnel junctions, electron-coupled phonon spectra were determined showing that superconductivity in MgB2 is phonon mediated. In a further analysis, which involves first principles calculations, the strongest feature in these spectra could be traced back to the key quantity of two-band superconductivity, the interband pairing interaction. For the phonons, this interaction turns out quite selective. It involves mainly low-energy optical phonon modes, where the boron atoms move perpendicular to the boron planes.

Journal Article↗
PubMed2005

What does "active disease" mean? patient and parent perceptions of disease activity in the systemic arthritis form of juvenile idiopathic arthritis (SO-JIA).

OBJECTIVE: The systemic onset form of juvenile idiopathic arthritis (SO-JIA) is a very serious chronic illness of childhood. At present, there is no specific tool to measure disease activity for SO-JIA. Our long-term goal is to develop a disease activity measure for SO-JIA using a consensus (Delphi) approach. In preparation for the development of this measure, we interviewed both patients and their parents. We sought to elicit specific items reflecting their perceptions of active disease that may be considered for inclusion in a disease activity measure for SO-JIA. METHODS: SO-JIA patients followed at The Hospital for Sick Children and their parents were chosen by purposive sampling. A trained research coordinator interviewed all participants using open-ended questions to elicit aspects of disease activity (defined as reversible manifestations of disease) of relevance to families. A list of these aspects was then generated and organized by categories to allow item reduction. RESULTS: Fourteen patients (eight females) with a mean age of 11.8 yr (mean disease duration 5.2 yr) and their parents were interviewed. A total of 292 items were generated, with an average of 11 items generated per interview. Arthralgia, ambulation difficulties, rash, decreased energy level and fever were the most common items mentioned by patients and their parents. Mood disturbances, decreased activity levels, arthritis severity and decreased school attendance were also common items identified as relevant aspects of disease activity. CONCLUSION: This study has allowed us to include patient and parent perspectives in preparation for developing a disease activity measure for SO-JIA. The resulting items will be added to future physician surveys in the further development and validation of a disease activity measure for SO-JIA.

Adolescent↗
PubMed2005

Linking disease-associated genes to regulatory networks via promoter organization.

Pathway- or disease-associated genes may participate in more than one transcriptional co-regulation network. Such gene groups can be readily obtained by literature analysis or by high-throughput techniques such as microarrays or protein-interaction mapping. We developed a strategy that defines regulatory networks by in silico promoter analysis, finding potentially co-regulated subgroups without a priori knowledge. Pairs of transcription factor binding sites conserved in orthologous genes (vertically) as well as in promoter sequences of co-regulated genes (horizontally) were used as seeds for the development of promoter models representing potential co-regulation. This approach was applied to a Maturity Onset Diabetes of the Young (MODY)-associated gene list, which yielded two models connecting functionally interacting genes within MODY-related insulin/glucose signaling pathways. Additional genes functionally connected to our initial gene list were identified by database searches with these promoter models. Thus, data-driven in silico promoter analysis allowed integrating molecular mechanisms with biological functions of the cell.

Binding Sites↗
PubMed2005

The effectiveness of treating juvenile dermatomyositis with methotrexate and aggressively tapered corticosteroids.

OBJECTIVE: Childhood dermatomyositis (DM) is often a chronic disease, lasting many years. It has traditionally been treated with long-term corticosteroid therapy; side effects are often seen. For more than a decade, methotrexate (MTX) has been safely used for the treatment of juvenile arthritis. Here, we report use of MTX as first-line therapy for DM, along with aggressively tapered corticosteroids, in an attempt to reduce treatment-related side effects. METHODS: We studied an inception cohort of 31 children with DM who were rigorously followed up in our myositis clinic, and compared them with a control group of 22 patients with incident cases of juvenile DM who received treatment just before we instituted a policy of first-line therapy with MTX. The mean starting dosage of MTX in the study group was 15 mg/m(2)/week. RESULTS: Both groups had similar improvement in strength and physical function; however, the median time during which patients in the study group received corticosteroids was 10 months, compared with 27 months for controls (P < 0.0001). As a result, the cumulative prednisone dose in the study group was approximately half that in the control group (7,574 mg versus 15,152 mg; P = 0.0006). The study group had greater height velocity during the first year of treatment and a smaller increase in the body mass index over the first 2 years. In the control group, the relative risk of cataracts developing was 1.95 (95% confidence interval 1.05-4.17). Side effects of MTX were rarely observed. CONCLUSION: Use of MTX in conjunction with an aggressively tapered course of prednisone may be as effective as traditional long-term corticosteroid therapy for children with DM, while decreasing the cumulative dose of corticosteroids.

Dermatomyositis↗
PubMed2005

[Interventional endovascular therapy (stenting) for residual stenosis after lysis of the basilar artery].

Despite the introduction of local thrombolytic therapy, there is still a very high mortality rate in basilar thrombosis. We report three cases of successful intra-arterial thrombolysis of acute basilar artery occlusion and consecutive interventional endovascular therapy. In all cases, the acute thrombosis of the basilar artery probably developed from preexisting atherosclerotic stenoses. The clinical outcomes were excellent. We discuss early consecutive stenting as a possible therapeutic option in cases of residual stenosis after successful intra-arterial lysis of basilar artery occlusion.

Basilar Artery↗
PubMed2004

Late intestinal fistula formation after incisional hernia using intraperitoneal mesh.

Enteric fistulas are a rare but serious complication following the repair of an incisional hernia using a prosthesis. We report the case of a 52-year-old man who developed an enterocolocutaneus fistula after incisional hernia repair with intra-abdominal polyester mesh. This case shows that one may want to avoid placing the parietal prostheses in direct contact with intestinal loops.

Cicatrix↗
PubMed2004

Strong temperature dependence of irradiation effects in organic layers.

Radiation damage of self-assembled monolayers, which are prototypes of thin organic layers and highly organized biological systems, shows a strong dependence on temperature. Two limiting cases could be identified. Reactions involving transport of single atoms and small fragments proceed nearly independent of temperature. Reactions requiring transport of heavy fragments are, however, efficiently quenched by cooling. We foresee the combined use of temperature and irradiation by electrons or photons for advanced tailoring of self-assembled monolayers on surfaces. In addition, our results have direct implications for cryogenic approaches in advanced electron and x-ray microscopy and spectroscopy of biological macromolecules and cells.

Biomimetic Materials↗