86 research outputs found
Saddle points in completely regular topological spaces
We give a characterization of completely regular topological spaces. Applying
some recent results for supinf problems in completely regular topological
spaces we establish a variational principle for saddle points. Well-posedness
of saddle point problems is studied as well
Linking changes in pain severity to changes in other outcomes in patients with posttraumatic peripheral neuropathic pain treated with pregabalin [POSTER]
No abstract available
Joint Assessment of Intended and Unintended Effects of Medications: An Example Using Vascular Endothelial Growth Factor Inhibitors for Neovascular Age-Related Macular Degeneration
Objective. To estimate the net health benefits of pegaptanib and ranibizumab by considering the impact of visual acuity and unintended effects (cardiovascular and hemorrhagic events) on quality-of-life among persons with neovascular age-related macular degeneration. Methods. We designed a probabilistic decision-analytic model using published data. It employed 17 visual health states and three for unintended effects. We calculated incremental net health benefits by subtracting the harms of each medication from the benefit using the quality-adjusted life year (QALY). Results. In a hypothetical cohort of 1,000 75-year olds with new-onset bilateral age-related macular degeneration followed for ten years, the mean QALYs per patient is 3.7 for usual care, 4.2 for pegaptanib, and 4.3 for ranibizumab. Net benefits decline with increasing baseline rates of unintended effects. Interpretation. Net health benefits present a quantitative, potentially useful tool to assist patients and ophthalmologists in balancing the benefits and harms of interventions for age-related macular degeneration
RATIONAL BASE OF A COMBINATION GENTAMICIN 0.1 % - UREA 0.2 % IN OINTMENT FORM DURING THE TREATMENT OF PATIENTS WITH SKIN BURNS
No abstrac
Cost-Effectiveness Model for Neovascular Age-Related Macular Degeneration: Comparing Early and Late Treatment with Pegaptanib Sodium Based on Visual Acuity
AbstractObjectiveTo compare the cost-effectiveness of pegaptanib and usual care within three distinct cohorts of subfoveal neovascular age-related macular degeneration (NV-AMD) patients, that is, those with early, moderate, and late disease, using a comprehensive economic model.MethodsA Markov framework was used to model lifetime movement of a subfoveal NV-AMD cohort through health states based on visual acuity. The model takes a US payer perspective of patients over the age of 65 years. Clinical efficacy was based on published results for the 0.3 mg pegaptanib and usual care groups. Expert interviews were conducted to determine adverse event treatment patterns and vision rehabilitation resource use. Incidence and costs of comorbidities such as depression and fractures associated with the effects of declining visual acuity were based on our previously published analysis of Medicare data. Transition probabilities were derived from published clinical trial data for each 3-month cycle. Utilities were derived from published sources. Three runs of the model were conducted with cohorts of newly diagnosed patients. Patients were classified as having early, moderate, or late NV-AMD defined as visual acuity in the better-seeing eye of 20/40 to more than 20/80, 20/80 to more than 20/200, and 20/200 to more than 20/400, respectively. Costs and outcomes were discounted 3.0% per annum.ResultsIncremental costs per vision-year gained and per quality-adjusted life-year (QALY) gained for early NV-AMD patients were approximately one-third those of patients with late disease (57,230 and 132,381, respectively). On average, patients treated early with either pegaptanib or usual care incurred lower lifetime total direct costs than those treated later. Sensitivity analysis showed that base-case incremental costs per QALY gained for pegaptanib versus usual care were relatively robust.ConclusionsFor patients with subfoveal NV-AMD, treatment with pegaptanib should be started as early as possible to maximize the clinical and economic benefits
Fluorescence analysis of the Hansenula polymorpha peroxisomal targeting signal-1 receptor, Pex5p
Correct sorting of newly synthesized peroxisomal matrix proteins is dependent on a peroxisomal targeting signal (PTS). So far two PTSs are known. PTS1 consists of a tripeptide that is located at the extreme C terminus of matrix proteins and is specifically recognized by the PTS1-receptor Pex5p. We studied Hansenula polymorpha Pex5p (HpPex5p) using fluorescence spectroscopy. The intensity of Trp fluorescence of purified HpPex5p increased by 25% upon shifting the pH from pH 6.0 to pH 7.2. Together with the results of fluorescence quenching by acrylamide, these data suggest that the conformation of HpPex5p differs at these two pH values. Fluorescence anisotropy decay measurements revealed that the pH affected the oligomeric state of HpPex5p, possibly from monomers/dimers at pH 6.0 to larger oligomeric forms at pH 7.2. Addition of dansylated peptides containing a PTS1, caused some shortening of the average fluorescence lifetime of the Trp residues, which was most pronounced at pH 7.2. Our data are discussed in relation to a molecular model of HpPex5p based on the three-dimensional structure of human Pex5p
Molecular Epidemiology and Evolution of Human Respiratory Syncytial Virus and Human Metapneumovirus
Human respiratory syncytial virus (HRSV) and human metapneumovirus (HMPV) are ubiquitous respiratory pathogens of the Pneumovirinae subfamily of the Paramyxoviridae. Two major surface antigens are expressed by both viruses; the highly conserved fusion (F) protein, and the extremely diverse attachment (G) glycoprotein. Both viruses comprise two genetic groups, A and B. Circulation frequencies of the two genetic groups fluctuate for both viruses, giving rise to frequently observed switching of the predominantly circulating group. Nucleotide sequence data for the F and G gene regions of HRSV and HMPV variants from the UK, the Netherlands, Bangkok and data available from Genbank were used to identify clades of both viruses. Several contemporary circulating clades of HRSV and HMPV were identified by phylogenetic reconstructions. The molecular epidemiology and evolutionary dynamics of clades were modelled in parallel. Times of origin were determined and positively selected sites were identified. Sustained circulation of contemporary clades of both viruses for decades and their global dissemination demonstrated that switching of the predominant genetic group did not arise through the emergence of novel lineages each respiratory season, but through the fluctuating circulation frequencies of pre-existing lineages which undergo proliferative and eclipse phases. An abundance of sites were identified as positively selected within the G protein but not the F protein of both viruses. For HRSV, these were discordant with previously identified residues under selection, suggesting the virus can evade immune responses by generating diversity at multiple sites within linear epitopes. For both viruses, different sites were identified as positively selected between genetic groups
Evaluation of the safety and efficacy of pregabalin in older patients with neuropathic pain: results from a pooled analysis of 11 clinical studies
Clinical risk factors for age-related macular degeneration: a systematic review and meta-analysis
BACKGROUND: Age-related macular degeneration (AMD) is the leading cause of blindness in Western countries. Numerous risk factors have been reported but the evidence and strength of association is variable. We aimed to identify those risk factors with strong levels of evidence which could be easily assessed by physicians or ophthalmologists to implement preventive interventions or address current behaviours. METHODS: A systematic review identified 18 prospective and cross-sectional studies and 6 case control studies involving 113,780 persons with 17,236 cases of late AMD that included an estimate of the association between late AMD and at least one of 16 pre-selected risk factors. Fixed-effects meta-analyses were conducted for each factor to combine odds ratio (OR) and/or relative risk (RR) outcomes across studies by study design. Overall raw point estimates of each risk factor and associated 95% confidence intervals (CI) were calculated. RESULTS: Increasing age, current cigarette smoking, previous cataract surgery, and a family history of AMD showed strong and consistent associations with late AMD. Risk factors with moderate and consistent associations were higher body mass index, history of cardiovascular disease, hypertension, and higher plasma fibrinogen. Risk factors with weaker and inconsistent associations were gender, ethnicity, diabetes, iris colour, history of cerebrovascular disease, and serum total and HDL cholesterol and triglyceride levels. CONCLUSIONS: Smoking, previous cataract surgery and a family history of AMD are consistent risk factors for AMD. Cardiovascular risk factors are also associated with AMD. Knowledge of these risk factors that may be easily assessed by physicians and general ophthalmologists may assist in identification and appropriate referral of persons at risk of AMD
Positive Selection Results in Frequent Reversible Amino Acid Replacements in the G Protein Gene of Human Respiratory Syncytial Virus
Human respiratory syncytial virus (HRSV) is the major cause of lower respiratory tract infections in children under 5 years of age and the elderly, causing annual disease outbreaks during the fall and winter. Multiple lineages of the HRSVA and HRSVB serotypes co-circulate within a single outbreak and display a strongly temporal pattern of genetic variation, with a replacement of dominant genotypes occurring during consecutive years. In the present study we utilized phylogenetic methods to detect and map sites subject to adaptive evolution in the G protein of HRSVA and HRSVB. A total of 29 and 23 amino acid sites were found to be putatively positively selected in HRSVA and HRSVB, respectively. Several of these sites defined genotypes and lineages within genotypes in both groups, and correlated well with epitopes previously described in group A. Remarkably, 18 of these positively selected tended to revert in time to a previous codon state, producing a “flip-flop” phylogenetic pattern. Such frequent evolutionary reversals in HRSV are indicative of a combination of frequent positive selection, reflecting the changing immune status of the human population, and a limited repertoire of functionally viable amino acids at specific amino acid sites
- …