53 research outputs found
Fixed Points of Hopfield Type Neural Networks
The set of the fixed points of the Hopfield type network is under
investigation. The connection matrix of the network is constructed according to
the Hebb rule from the set of memorized patterns which are treated as distorted
copies of the standard-vector. It is found that the dependence of the set of
the fixed points on the value of the distortion parameter can be described
analytically. The obtained results are interpreted in the terms of neural
networks and the Ising model.Comment: RevTEX, 19 pages, 2 Postscript figures, the full version of the
earler brief report (cond-mat/9901251
СОВРЕМЕННАЯ ЛУЧЕВАЯ ТЕРАПИЯ ЖЕЛУДКА
External beam radiation therapy (EBRT) is currently an important component of the treatment of gastric cancer (GC). In accordance with international and domestic recommendations, it can be used in the postoperative period, before the operation and as a sole option, with a curative and palliative purpose, usually in combination with chemotherapy. With the transition of RT to a new technological level, which involves the use of conformal, intensively modulated regimens, and image guidance the revision of indications for and doses of EBRT is required. The article discusses modern approaches to the determination of irradiated volumes in various clinical scenarios of current radiation therapy for GC and strategies aimed at reducing the dose in critical organs at risk and increasing the overall effectiveness of treatment.Дистанционная лучевая терапия (ЛТ) в настоящее время является важным компонентом лечения рака желудка (РЖ). В соответствии с международными и отечественными рекомендациями она может быть использована в послеоперационном периоде, перед операцией и самостоятельно, с лечебной и паллиативной целью, как правило, в сочетании с химиотерапией. В связи с переходом ЛТ на новый технологический уровень, предусматривающий использование конформных, интенсивно-модулированных режимов, требуется пересмотр показаний, доз и режимов дистанционного облучения. В статье рассмотрены современные подходы к определению облучаемых объемов при различных клинических сценариях современной ЛТ по поводу РЖ и обсуждены стратегии, направленные на снижение дозы в критических органах и повышение эффективности лечения
Nintedanib for Systemic Sclerosis-Associated Interstitial Lung Disease
BACKGROUND: Interstitial lung disease (ILD) is a common manifestation of systemic sclerosis and a leading cause of systemic sclerosis-related death. Nintedanib, a tyrosine kinase inhibitor, has been shown to have antifibrotic and antiinflammatory effects in preclinical models of systemic sclerosis and ILD. METHODS: We conducted a randomized, double-blind, placebo-controlled trial to investigate the efficacy and safety of nintedanib in patients with ILD associated with systemic sclerosis. Patients who had systemic sclerosis with an onset of the first non-Raynaud's symptom within the past 7 years and a high-resolution computed tomographic scan that showed fibrosis affecting at least 10% of the lungs were randomly assigned, in a 1:1 ratio, to receive 150 mg of nintedanib, administered orally twice daily, or placebo. The primary end point was the annual rate of decline in forced vital capacity (FVC), assessed over a 52-week period. Key secondary end points were absolute changes from baseline in the modified Rodnan skin score and in the total score on the St. George's Respiratory Questionnaire (SGRQ) at week 52. RESULTS: A total of 576 patients received at least one dose of nintedanib or placebo; 51.9% had diffuse cutaneous systemic sclerosis, and 48.4% were receiving mycophenolate at baseline. In the primary end-point analysis, the adjusted annual rate of change in FVC was 1252.4 ml per year in the nintedanib group and 1293.3 ml per year in the placebo group (difference, 41.0 ml per year; 95% confidence interval [CI], 2.9 to 79.0; P=0.04). Sensitivity analyses based on multiple imputation for missing data yielded P values for the primary end point ranging from 0.06 to 0.10. The change from baseline in the modified Rodnan skin score and the total score on the SGRQ at week 52 did not differ significantly between the trial groups, with differences of 120.21 (95% CI, 120.94 to 0.53; P=0.58) and 1.69 (95% CI, 120.73 to 4.12 [not adjusted for multiple comparisons]), respectively. Diarrhea, the most common adverse event, was reported in 75.7% of the patients in the nintedanib group and in 31.6% of those in the placebo group. CONCLUSIONS: Among patients with ILD associated with systemic sclerosis, the annual rate of decline in FVC was lower with nintedanib than with placebo; no clinical benefit of nintedanib was observed for other manifestations of systemic sclerosis. The adverse-event profile of nintedanib observed in this trial was similar to that observed in patients with idiopathic pulmonary fibrosis; gastrointestinal adverse events, including diarrhea, were more common with nintedanib than with placebo
Predictors of disease worsening defined by progression of organ damage in diffuse systemic sclerosis: a European Scleroderma Trials and Research (EUSTAR) analysis.
Objectives Mortality and worsening of organ function are desirable endpoints for clinical trials in systemic sclerosis (SSc). The aim of this study was to identify factors that allow enrichment of patients with these endpoints, in a population of patients from the European Scleroderma Trials and Research group database. Methods Inclusion criteria were diagnosis of diffuse SSc and follow-up over 12\ub13 months. Disease worsening/organ progression was fulfilled if any of the following events occurred: new renal crisis; decrease of lung or heart function; new echocardiography-suspected pulmonary hypertension or death. In total, 42 clinical parameters were chosen as predictors for the analysis by using (1) imputation of missing data on the basis of multivariate imputation and (2) least absolute shrinkage and selection operator regression. Results Of 1451 patients meeting the inclusion criteria, 706 had complete data on outcome parameters and were included in the analysis. Of the 42 outcome predictors, eight remained in the final regression model. There was substantial evidence for a strong association between disease progression and age, active digital ulcer (DU), lung fibrosis, muscle weakness and elevated C-reactive protein (CRP) level. Active DU, CRP elevation, lung fibrosis and muscle weakness were also associated with a significantly shorter time to disease progression. A bootstrap validation step with 10 000 repetitions successfully validated the model. Conclusions The use of the predictive factors presented here could enable cohort enrichment with patients at risk for overall disease worsening in SSc clinical trial
Efficacy and Safety of Lenabasum, a Cannabinoid Type 2 Receptor Agonist, in a Phase 3 Randomized Trial in Diffuse Cutaneous Systemic Sclerosis
Objective
This phase 3 study was undertaken to investigate the efficacy and safety of lenabasum, a cannabinoid type 2 receptor agonist, in patients with diffuse cutaneous systemic sclerosis (dcSSc).
Methods
A multinational double-blind study was conducted in 365 dcSSc patients who were randomized and dosed 1:1:1 with lenabasum 20 mg, lenabasum 5 mg, or placebo, each twice daily and added to background treatments, including immunosuppressive therapies (IST).
Results
The primary end point, the American College of Rheumatology combined response index in dcSSc (CRISS) at week 52 for lenabasum 20 mg twice a day versus placebo, was not met, with CRISS score of 0.888 versus 0.887 (P = 0.4972, using mixed models repeated measures [MMRM]). The change in the modified Rodnan skin thickness score (MRSS) at week 52 for lenabasum 20 mg twice a day versus placebo was −6.7 versus −8.1 (P = 0.1183, using MMRM). Prespecified analyses showed higher CRISS scores, greater improvement in MRSS, and lower decline in forced vital capacity in patients on background mycophenolate and those who were taking IST for ≤1 year. No deaths or excess in serious or severe adverse events related to lenabasum were observed.
Conclusion
A benefit of lenabasum in dcSSc was not demonstrated. Most patients were treated with background IST, and treatment with mycophenolate mofetil in particular was associated with better outcomes. These findings support the use of IST in the treatment of dcSSc and highlight the challenge of demonstrating a treatment effect when investigational treatment is added to standard of care IST. These findings have relevance to trial design in SSc, as well as to clinical care
Phenotypes Determined by Cluster Analysis and Their Survival in the Prospective European Scleroderma Trials and Research Cohort of Patients With Systemic Sclerosis
Objective: Systemic sclerosis (SSc) is a heterogeneous connective tissue disease that is typically subdivided into limited cutaneous SSc (lcSSc) and diffuse cutaneous SSc (dcSSc) depending on the extent of skin involvement. This subclassification may not capture the entire variability of clinical phenotypes. The European Scleroderma Trials and Research (EUSTAR) database includes data on a prospective cohort of SSc patients from 122 European referral centers. This study was undertaken to perform a cluster analysis of EUSTAR data to distinguish and characterize homogeneous phenotypes without any a priori assumptions, and to examine survival among the clusters obtained. /
Methods: A total of 11,318 patients were registered in the EUSTAR database, and 6,927 were included in the study. Twenty‐four clinical and serologic variables were used for clustering. /
Results: Clustering analyses provided a first delineation of 2 clusters showing moderate stability. In an exploratory attempt, we further characterized 6 homogeneous groups that differed with regard to their clinical features, autoantibody profile, and mortality. Some groups resembled usual dcSSc or lcSSc prototypes, but others exhibited unique features, such as a majority of lcSSc patients with a high rate of visceral damage and antitopoisomerase antibodies. Prognosis varied among groups and the presence of organ damage markedly impacted survival regardless of cutaneous involvement. /
Conclusion: Our findings suggest that restricting subsets of SSc patients to only those based on cutaneous involvement may not capture the complete heterogeneity of the disease. Organ damage and antibody profile should be taken into consideration when individuating homogeneous groups of patients with a distinct prognosis
EP-1068: Chemoradiation may improve survival in locally advanced inoperable gastric carcinoma
СОВРЕМЕННАЯ ЛУЧЕВАЯ ТЕРАПИЯ ЖЕЛУДКА
External beam radiation therapy (EBRT) is currently an important component of the treatment of gastric cancer (GC). In accordance with international and domestic recommendations, it can be used in the postoperative period, before the operation and as a sole option, with a curative and palliative purpose, usually in combination with chemotherapy. With the transition of RT to a new technological level, which involves the use of conformal, intensively modulated regimens, and image guidance the revision of indications for and doses of EBRT is required. The article discusses modern approaches to the determination of irradiated volumes in various clinical scenarios of current radiation therapy for GC and strategies aimed at reducing the dose in critical organs at risk and increasing the overall effectiveness of treatment.Дистанционная лучевая терапия (ЛТ) в настоящее время является важным компонентом лечения рака желудка (РЖ). В соответствии с международными и отечественными рекомендациями она может быть использована в послеоперационном периоде, перед операцией и самостоятельно, с лечебной и паллиативной целью, как правило, в сочетании с химиотерапией. В связи с переходом ЛТ на новый технологический уровень, предусматривающий использование конформных, интенсивно-модулированных режимов, требуется пересмотр показаний, доз и режимов дистанционного облучения. В статье рассмотрены современные подходы к определению облучаемых объемов при различных клинических сценариях современной ЛТ по поводу РЖ и обсуждены стратегии, направленные на снижение дозы в критических органах и повышение эффективности лечения.</p
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