167 research outputs found
The Application of Half-Life in Clinical Decision Making: Comparison of the Pharmacokinetics of Extended-Release Topiramate (USL255) and Immediate-Release Topiramate
Objective: For extended-release drugs with multi-compartment kinetics, such as topiramate, effective half-life (t1/2eff) may be a more clinically relevant parameter than elimination half-life (t1/2z). Using topiramate as a real-life example, the objective was to compare these half-life values for immediate- and extended-release topiramate (TPM-IR and USL255, respectively) to understand how drug pharmacokinetics may impact drug dosing recommendations.
Methods: The t1/2z and t1/2eff for USL255 and TPM-IR were compared using data from a phase I study (N = 36) of 200 mg USL255 administered once daily (QD) or TPM-IR twice daily (BID); effect of sampling duration on t1/2z was investigated. To further explore the relationship between half-life and dosing, steady-state PK was simulated for USL255 and TPM-IR.
Results: As previously reported, mean t1/2z was similar between USL255 (80.2 h) and TPM-IR (82.8 h); TPM-IR t1/2z was âŒ4 times longer than reported in the Topamax label (21 h). In contrast, USL255 displayed a 1.5 fold longer t1/2eff (55.7 vs 37.1 h for TPM-IR). When t1/2z was calculated from 48 to 336 h, values ranged from 28.8 to 82.8 h. Simulated steady-state PK profiles of USL255 QD exhibited reduced plasma fluctuations during a dosing interval vs TPM-IR QD or BID.
Significance: As expected for the same moiety, t1/2z of USL255 and TPM-IR were similar; however, the longer t1/2eff for USL255 better approximates differences in recommend dosing (QD USL255 vs BID TPM-IR). Further, sampling duration impacted t1/2z, diminishing its predictive value for determining dose regimens; sampling-time differences may also explain t1/2z discrepancy between TPM-IR here versus Topamax label. As expected, steady-state simulations confirm that although TPM-IR has a long t1/2z, taking TPM-IR QD would lead to large plasma fluctuations. These data demonstrate that t1/2z may be less clinically meaningful than t1/2eff, and using t1/2z for some drugs may lead to erroneous conclusions regarding dosing regimens
Accounting for Misclassification in Multispecies Distribution Models
1. Species identification errors may have severe implications for the
inference of species distributions. Accounting for misclassification in species
distributions is an important topic of biodiversity research. With an
increasing amount of biodiversity that comes from Citizen Science projects,
where identification is not verified by preserved specimens, this issue is
becoming more important. This has often been dealt with by accounting for false
positives in species distribution models. However, the problem should account
for misclassifications in general.
2. Here we present a flexible framework that accounts for misclassification
in the distribution models and provides estimates of uncertainty around these
estimates. The model was applied to data on viceroy, queen and monarch
butterflies in the United States. The data were obtained from the iNaturalist
database in the period 2019 to 2020.
3. Simulations and analysis of butterfly data showed that the proposed model
was able to correct the reported abundance distribution for misclassification
and also predict the true state for misclassified state
Efficacy of once-daily extended-release topiramate (USL255): A subgroup analysis based on the level of treatment resistance
AbstractResults from a previously conducted global phase III study (PREVAIL; NCT01142193) demonstrate the safety and efficacy of once-daily USL255, Qudexyâą XR (topiramate) extended-release capsules, as adjunctive treatment of drug-resistant partial-onset seizures (POSs). In this study, we report a post hoc analysis of PREVAIL data according to patient level of treatment resistance (based upon the number of concomitant antiepileptic drugs [AEDs] and lifetime AEDs) at baseline, with patients defined as either having âhighlyâ drug-resistant seizures (â„2 concurrent AEDs and â„4 lifetime AEDs) or having âlessâ drug-resistant seizures (1 concurrent AED or <4 lifetime AEDs) at baseline. For each subgroup, median percent reduction in POS frequency (primary endpoint), responder rate, Clinical Global Impression of Change (CGI-C), and Quality of Life in Epilepsy â Problems (QOLIE-31-P) survey were assessed. Of 249 PREVAIL patients, 115 were classified as having highly drug-resistant seizures (USL255: n=52, placebo: n=63), and 134 were classified as having less drug-resistant seizures (USL255: n=72, placebo: n=62) at baseline. For the primary endpoint, USL255 resulted in significantly better seizure outcomes compared with placebo regardless of drug-resistant status (P=.004 and P=.040 for âhighlyâ and âlessâ, respectively). Responder rate was also significantly improved in patients with highly drug-resistant group (P=.023). The CGI-C scores indicated significant improvement in both subgroups (P=.003 and P=.013 for âhighlyâ and âlessâ, respectively). On the QOLIE-31-P, a significant improvement on the seizure worry subscale for the group with less drug-resistant seizures was noted in USL255-treated patients compared with placebo-treated patients (P=.003); the overall score and all other subscales were not significantly different for both subgroups. We conclude that USL255 led to significant improvements across multiple outcomes compared with placebo, including in those classified as having highly drug-resistant seizures to prior treatment, making it a valuable treatment option for patients with epilepsy
Forests and the climate: manage for maximum wood production or leave the forest as a carbon sink?
Apolipoprotein E Genotype and the Diagnostic Accuracy of Cerebrospinal Fluid Biomarkers for Alzheimer Disease.
Several studies suggest that the apolipoprotein E (APOE) Δ4 allele modulates cerebrospinal fluid (CSF) levels of ÎČ-amyloid 42 (AÎČ42). Whether this effect is secondary to the association of the APOE Δ4 allele with cortical AÎČ deposition or whether APOE Δ4 directly influences CSF levels of AÎČ42 independently of AÎČ pathology remains unknown
Evaluating the UV-C sensitivity of Coxiella burnetii in skim milk using a bench-scale collimated beam system and comparative thermal sensitivity study by high-temperature short-time pasteurization
Introduction:Coxiella burnetii is a zoonotic Gram-negative obligate intracellular bacterial pathogen and the causative agent of query (Q) fever in humans. Contamination of milk by C. burnetii, as a consequence of livestock infection, is a significant public health concern. Effective methods to inactivate C. burnetii in milk are a critical aspect of food safety. Implementation of non-thermal UV-C processing technologies in the dairy industry can effectively preserve the sensory and nutritional quality of raw milk products while ensuring their safety, making them a viable alternative to traditional high-temperature short-time (HTST) pasteurization methods.Methods: Optical light attenuation factors, such as the absorption, scattering, and reflection by skim milk (SM) were evaluated using a spectrophotometer. SM inoculated with an avirulent strain of C. burnetii was irradiated using a collimated beam device equipped with a low-pressure UV-C 254 nm lamp at doses from 0 to 12 mJ/cm2. Optical properties were considered for the evaluation of the delivered UV-C dose. The pasteurization treatment was conducted using a lab scale HTST pasteurizer (72°C/15 s). The verification studies were conducted using Escherichia coli ATCC 25922 inoculated in a phosphate buffer (transparent fluid) and humic acid (opaque fluid). Salmonella enterica serovar Muenchen ATCC BAA 1674 inoculated in SM was tested for its suitability as a surrogate for C. burnetii, a bacterium that requires specialized equipment and expertise for experimentation.Results and Discussion: Absorption, reduced scattering coefficient, and the reflectance of SM at 254 nm were measured as 19 ± 0.3/cm, 26 ± 0.5/cm, and 10.6%, respectively. The UV-C results showed a log-linear inactivation of C. burnetii in SM with the UV-C sensitivity (D10) value of 4.1 ± 0.04 mJ/cm2. The results of HTST pasteurization revealed that C. burnetii was heat-sensitive with a D value of 1.75 min. Salmonella Muenchen showed similar UV inactivation kinetics and is, thereby, suggested as a suitable surrogate to C. burnetii for the pilot-scale UV-C processing studies of SM
Impact of Untimely Access to Formal Care on Costs and Quality of Life in Community Dwelling People with Dementia
Needs and quality of life of people with middle-stage dementia and their family carers from the European Actifcare study. When informal care alone may not suffice
Funding: The project is supported through the following funding organizations under the aegis of JPND â www.jpnd.eu [grant number 733051001]. Germany, Ministry of Education and Research, Ireland, Health research board, Italy, Ministry of Health, the Netherlands, The Netherlands organization for Health Research and Development, Sweden, The Swedish Research Council for Health, Working Life and Welfare, Norway, The Research Council of Norway, Portugal, Foundation for Science and Technology (Fundacžao para a Ci ~ ^encia e Tecnologia [grant number FCTâ JPND-HC/ 0001/2012], United Kingdom, Economic and Social Research Council. JPND has read and approved of the protocol of the Actifcare study.OBJECTIVE: The Actifcare (Access to timely formal care) study investigated needs of people with dementia and their families during the phase in which formal care is being considered, and examined whether higher need levels are related to lower quality of life (QOL). METHOD: From eight European countries 451 people with dementia and their carers participated. Needs were measured with the Camberwell Assessment of Need for the Elderly. QOL was measured with the QOL-AD, and carer quality of life was measured with the CarerQol. The relationship between needs and QOL was analysed with multiple regression analyses. RESULTS: Needs were expressed in the domains of psychological distress, daytime activities, company and information. People with dementia rated their unmet needs significantly lower than their carers: the mean number of self-rated unmet needs was 0.95, whereas the mean proxy ratings were 1.66. For met needs, the self-rated mean was 5.5 and was 8 when proxy-rated. The level of needs reported was negatively associated with QOL for both. CONCLUSION: The study results show that informal carers reported almost twice as many needs as people with dementia. The domains in which needs are expressed should be the primary focus for interventions to support QOL. The perspectives of people with dementia are informative when identifying needs.publishersversionpublishe
Needs and quality of life of people with middle-stage dementia and their family carers from the European Actifcare study. When informal care alone may not suffice
Objective: The Actifcare (Access to timely formal care) study investigated needs of people with dementia and their families during the phase in which formal care is being considered, and examined whether higher need levels are related to lower quality of life (QOL).Method: From eight European countries 451 people with dementia and their carers participated. Needs were measured with the Camberwell Assessment of Need for the Elderly. QOL was measured with the QOL-AD, and carer quality of life was measured with the CarerQol. The relationship between needs and QOL was analysed with multiple regression analyses.Results: Needs were expressed in the domains of psychological distress, daytime activities, company and information. People with dementia rated their unmet needs significantly lower than their carers: the mean number of self-rated unmet needs was 0.95, whereas the mean proxy ratings were 1.66. For met needs, the self-rated mean was 5.5 and was 8 when proxy-rated. The level of needs reported was negatively associated with QOL for both.Conclusion: The study results show that informal carers reported almost twice as many needs as people with dementia. The domains in which needs are expressed should be the primary focus for interventions to support QOL.The perspectives of people with dementia are informative when identifying needs
Do caregiver profiles predict the use of dementia care services? Findings from the Actifcare study
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