Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
287
result(s) for
"Dose dependency"
Sort by:
WO3 Photocatalyst Containing Copper Inactivates SARS-CoV-2 Pango Lineage A and Omicron BA.2 Variant in Visible Light and in Darkness
by
Hagiwara, Kyoji
,
Matsuura, Ryosuke
,
Mori, Yosuke
in
Air purification
,
antiviral properties
,
Copper
2022
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019, which has been a global pandemic. Since SARS-CoV-2 is transmitted through contaminated surfaces and aerosols, environmental disinfection is important to block the spread of the virus. Photocatalysts are attractive tools for virus inactivation and are widely used as air purifiers and coating materials. However, photocatalysts are inactive in the dark, and some of them need to be excited with light of a specific wavelength. Therefore, photocatalysts that can effectively inactivate SARS-CoV-2 in indoor environments are needed. Here, we show that a WO3 photocatalyst containing copper inactivated the SARS-CoV-2 WK-521 strain (Pango lineage A) upon irradiation with white light in a time- and concentration-dependent manner. Additionally, this photocatalyst also inactivated SARS-CoV-2 in dark conditions due to the antiviral effect of copper. Furthermore, this photocatalyst inactivated not only the WK-521 strain but also the Omicron variant BA.2. These results indicate that the WO3 photocatalyst containing copper can inactivate indoor SARS-CoV-2 regardless of the variant, in visible light or darkness, making it an effective tool for controlling the spread of SARS-CoV-2.
Journal Article
Comparative risk of major congenital malformations with eight different antiepileptic drugs: a prospective cohort study of the EURAP registry
by
Cagnetti, Claudia
,
Worm, Mogens
,
Turner, Katherine
in
Abnormalities, Drug-Induced - epidemiology
,
Adult
,
Anticonvulsants - therapeutic use
2018
Evidence for the comparative teratogenic risk of antiepileptic drugs is insufficient, particularly in relation to the dosage used. Therefore, we aimed to compare the occurrence of major congenital malformations following prenatal exposure to the eight most commonly used antiepileptic drugs in monotherapy.
We did a longitudinal, prospective cohort study based on the EURAP international registry. We included data from pregnancies in women who were exposed to antiepileptic drug monotherapy at conception, prospectively identified from 42 countries contributing to EURAP. Follow-up data were obtained after each trimester, at birth, and 1 year after birth. The primary objective was to compare the risk of major congenital malformations assessed at 1 year after birth in offspring exposed prenatally to one of eight commonly used antiepileptic drugs (carbamazepine, lamotrigine, levetiracetam, oxcarbazepine, phenobarbital, phenytoin, topiramate, and valproate) and, whenever a dose dependency was identified, to compare the risks at different dose ranges. Logistic regression was used to make direct comparisons between treatments after adjustment for potential confounders and prognostic factors.
Between June 20, 1999, and May 20, 2016, 7555 prospective pregnancies met the eligibility criteria. Of those eligible, 7355 pregnancies were exposed to one of the eight antiepileptic drugs for which the prevalence of major congenital malformations was 142 (10·3%) of 1381 pregnancies for valproate, 19 (6·5%) of 294 for phenobarbital, eight (6·4%) of 125 for phenytoin, 107 (5·5%) of 1957 for carbamazepine, six (3·9%) of 152 for topiramate, ten (3·0%) of 333 for oxcarbazepine, 74 (2·9%) of 2514 for lamotrigine, and 17 (2·8%) of 599 for levetiracetam. The prevalence of major congenital malformations increased with the dose at time of conception for carbamazepine (p=0·0140), lamotrigine (p=0·0145), phenobarbital (p=0·0390), and valproate (p<0·0001). After adjustment, multivariable analysis showed that the prevalence of major congenital malformations was significantly higher for all doses of carbamazepine and valproate as well as for phenobarbital at doses of more than 80 mg/day than for lamotrigine at doses of 325 mg/day or less. Valproate at doses of 650 mg/day or less was also associated with increased risk of major congenital malformations compared with levetiracetam at doses of 250–4000 mg/day (odds ratio [OR] 2·43, 95% CI 1·30–4·55; p=0·0069). Carbamazepine at doses of more than 700 mg/day was associated with increased risk of major congenital malformations compared with levetiracetam at doses of 250–4000 mg/day (OR 2·41, 95% CI 1·33–4·38; p=0·0055) and oxcarbazepine at doses of 75–4500 mg/day (2·37, 1·17–4·80; p=0·0169).
Different antiepileptic drugs and dosages have different teratogenic risks. Risks of major congenital malformation associated with lamotrigine, levetiracetam, and oxcarbazepine were within the range reported in the literature for offspring unexposed to antiepileptic drugs. These findings facilitate rational selection of these drugs, taking into account comparative risks associated with treatment alternatives. Data for topiramate and phenytoin should be interpreted cautiously because of the small number of exposures in this study.
Bial, Eisai, GlaxoSmithKline, Janssen-Cilag, Novartis, Pfizer, Sanofi-Aventis, UCB, the Netherlands Epilepsy Foundation, and Stockholm County Council.
Journal Article
Dose Dependency of Iatrogenic Glucocorticoid Excess and Adrenal Insufficiency and Mortality: A Cohort Study in England
by
Mebrahtu, Teumzghi F
,
Baxter, Paul D
,
Stewart, Paul M
in
Adrenal glands
,
Adrenocorticotropic hormone
,
Clinical s
2019
Abstract
Context
Adrenal insufficiency and Cushing syndrome are known adverse events of glucocorticoids. However, no population estimates of dose-related risks are available.
Objective
To investigate dose-related risks of adrenal dysfunction and death in adults with six chronic inflammatory diseases treated with oral glucocorticoids.
Design and setting
Retrospective, record-linkage, open-cohort study spanning primary and hospital care in England.
Patients
A total of 70,638 oral glucocorticoid users and 41,166 nonusers aged ≥18 years registered in 389 practices in 1998 to 2017.
Main outcome measures
Incidence rates and hazard ratios (HRs) of diagnosed adrenal dysfunction and death.
Results
During a median follow-up of 5.5 years, 183 patients had glucocorticoid-induced adrenal insufficiency and 248 had glucocorticoid-induced Cushing syndrome. A total of 22,317 (31.6%) and 7544 (18.3%) deaths occurred among glucocorticoid users and nonusers, respectively. The incidence of all outcomes increased with higher current daily and cumulative doses. For adrenal insufficiency, the increases in HRs were 1.07 (95% CI: 1.04 to 1.09) for every increase of 5 mg per day and 2.25 (95% CI: 2.15 to 2.35) per 1000 mg of cumulative prednisolone-equivalent dose over the past year. The respective increases in HRs for Cushing syndrome were 1.09 (95% CI: 1.08 to 1.11) and 2.31 (95% CI: 2.23 to 2.40) and for mortality 1.26 (95% CI: 2.24 to 1.28) and 2.05 (95% CI: 2.04 to 2.06).
Conclusion
We report a high glucocorticoid dose-dependent increased risk of adrenal adverse events and death. The low observed absolute risk of adrenal insufficiency highlights a potential lack of awareness and a need for increased physician and patient education about the risks of adrenal dysfunction induced by glucocorticoids.
In this cohort study, we found high glucocorticoid dose-dependent increased risks of adrenal dysfunction and death but low absolute risks, indicating potential underdiagnosis in clinical practice.
Journal Article
Dose Dependency and a Functional Cutoff for TPO-Antibody Positivity During Pregnancy
by
Chaker, Layal
,
Broeren, Maarten A
,
Bisschop, Peter H
in
Autoimmunity
,
Children
,
Dose dependency
2018
Abstract To investigate a dose dependency of thyroperoxidase antibody (TPOAb) concentrations in relation to thyroid function and premature delivery and define a population-based, pregnancy-specific, functional cutoff for TPOAb positivity. Individual participant meta-analysis of three prospective birth cohorts: the Amsterdam Born Children and their Development study, and the Holistic Approach to Pregnancy. Population-based studies in the Netherlands (2002 to 2014). A total of 11,212 pregnant women (<20 weeks' gestation). Thyrotropin (TSH) and FT4 concentrations, premature delivery. In all cohorts, there was a dose-dependent positive association of TPOAb concentrations with TSH concentrations, as well as a dose-dependent negative association with FT4 concentrations during early pregnancy (all P < 0.0001). There was a dose-dependent association of TPOAb concentrations with the risk of premature delivery, which was also modified by TSH concentrations. Women with TPOAb concentrations from the 92nd percentile upward had a higher TSH and a higher risk of a TSH >2.5 mU/L (range, 19.4% to 51.3%). Stratified analyses showed that women with TPOAb concentrations below manufacturer cutoffs already had a higher risk of premature delivery, especially when TSH concentrations were high or in the high-normal range. This study demonstrated a dose-dependent relationship between TPOAbs and thyroid function as well as the risk of premature delivery. Furthermore, our results indicate that the currently used cutoffs for TPOAb positivity may be too high. Furthermore, the use of a population-based cutoff for TPOAbs may identify women with a clinically relevant extent of thyroid autoimmunity and a higher risk of premature delivery but that would not be considered TPOAb positive or eligible for treatment otherwise. In this study, we show a dose-dependent relationship of TPOAbs with thyroid function and premature delivery risk and define a population-based cutoff for TPOAb positivity accordingly.
Journal Article
Is Clozapine-induced Weight Gain Dose-dependent? Results From a Prospective Cohort Study
by
Grosu, Claire
,
von Gunten, Armin
,
Ranjbar, Setareh
in
Cohort analysis
,
Drug dosages
,
Metabolism
2023
Background
Antipsychotic-induced metabolic adverse effects are risk factors for cardiometabolic comorbidities. Whether dose lowering could mitigate such effects remains unclear. The present study aims to investigate the associations between clozapine doses and modifications of weight, blood pressure, blood glucose, and lipid levels.
Study Design
Linear mixed-effects models of weight changes over 1 year and of variations of other metabolic parameters over 4 months were applied to a prospective cohort of 115 patients. Age- and sex-stratified analyses of weight changes were also performed.
Study Results
Each 100 mg dose increment of clozapine was associated on average with a +0.48% weight increase (P = .004) over 1 year of treatment. Weight increase was greater for treatment duration ≤3 vs >3 months (+0.84% and +0.47% per month, respectively, P < .001), with a significant association with the dose for durations >3 months (+0.54%, P = .004) and a trend for durations ≤3 months (+0.33%, P = .075). Dose increments of 100 mg were also associated with weight increases of +0.71% among adults (P = .001), +1.91% among the elderly (P < .001) and +1.32% among men (P < .001) with no associations among women (P = .62). Among young adults, weight change was positively associated with doses ≤300 mg/day (+2.19% per 100 mg, P = .001), whereas no association was found with doses >300 mg/day (P = .60). No significant effect of clozapine dose on other metabolic parameters was found.
Conclusions
This study reports a modest effect of clozapine dose increases on weight gain over 1 year with differences among age categories and sexes and no dose effect on other metabolic parameters over 4 months.
Journal Article
Diagnosis of osteoporosis in statin-treated patients is dose-dependent
2019
ObjectiveWhether HMG-CoA-reductase inhibition, the main mechanism of statins, plays a role in the pathogenesis of osteoporosis, is not entirely known so far. Consequently, this study was set out to investigate the relationship of different kinds and dosages of statins with osteoporosis, hypothesising that the inhibition of the synthesis of cholesterol could influence sex-hormones and therefore the diagnosis of osteoporosis.MethodsMedical claims data of all Austrians from 2006 to 2007 was used to identify all patients treated with statins to compute their daily defined dose averages of six different types of statins. We applied multiple logistic regression to analyse the dose-dependent risks of being diagnosed with osteoporosis for each statin individually.ResultsIn the general study population, statin treatment was associated with an overrepresentation of diagnosed osteoporosis compared with controls (OR: 3.62, 95% CI 3.55 to 3.69, p<0.01). There was a highly non-trivial dependence of statin dosage with the ORs of osteoporosis. Osteoporosis was underrepresented in low-dose statin treatment (0–10 mg per day), including lovastatin (OR: 0.39, CI 0.18 to 0.84, p<0.05), pravastatin (OR: 0.68, 95% CI 0.52 to 0.89, p<0.01), simvastatin (OR: 0.70, 95% CI 0.56 to 0.86, p<0.01) and rosuvastatin (OR: 0.69, 95% CI 0.55 to 0.87, p<0.01). However, the exceeding of the 40 mg threshold for simvastatin (OR: 1.64, 95% CI 1.31 to 2.07, p<0.01), and the exceeding of a 20 mg threshold for atorvastatin (OR: 1.78, 95% CI 1.41 to 2.23, p<0.01) and for rosuvastatin (OR: 2.04, 95% CI 1.31 to 3.18, p<0.01) was related to an overrepresentation of osteoporosis.ConclusionOur results show that the diagnosis of osteoporosis in statin-treated patients is dose-dependent. Thus, osteoporosis is underrepresented in low-dose and overrepresented in high-dose statin treatment, demonstrating the importance of future studies’ taking dose-dependency into account when investigating the relationship between statins and osteoporosis.
Journal Article
Evidence for formation of DNA repair centers and dose-response nonlinearity in human cells
by
Asaithamby, Aroumougame
,
Thalhammer, Stefan
,
Swenson, Joel
in
binding proteins
,
Binding sites
,
Biological Sciences
2012
The concept of DNA \"repair centers\" and the meaning of radiation-induced foci (RIF) in human cells have remained controversial. RIFs are characterized by the local recruitment of DNA damage sensing proteins such as p53 binding protein (53BP1). Here, we provide strong evidence for the existence of repair centers. We used live imaging and mathematical fitting of RIF kinetics to show that RIF induction rate increases with increasing radiation dose, whereas the rate at which RIFs disappear decreases. We show that multiple DNA double-strand breaks (DSBs) 1 to 2 μm apart can rapidly cluster into repair centers. Correcting mathematically for the dose dependence of induction/resolution rates, we observe an absolute RIF yield that is surprisingly much smaller at higher doses: 15 RIF/Gy after 2 Gy exposure compared to approximately 64 RIF/Gy after 0.1 Gy. Cumulative RIF counts from time lapse of 53BP1-GFP in human breast cells confirmed these results. The standard model currently in use applies a linear scale, extrapolating cancer risk from high doses to low doses of ionizing radiation. However, our discovery of DSB clustering over such large distances casts considerable doubts on the general assumption that risk to ionizing radiation is proportional to dose, and instead provides a mechanism that could more accurately address risk dose dependency of ionizing radiation.
Journal Article
Inter-individual variability in cortical excitability and motor network connectivity following multiple blocks of rTMS
by
Pool, Eva-Maria
,
Nettekoven, Charlotte
,
Eickhoff, Simon B.
in
Adult
,
Cortical plasticity
,
Dose-dependency
2015
The responsiveness to non-invasive neuromodulation protocols shows high inter-individual variability, the reasons of which remain poorly understood. We here tested whether the response to intermittent theta-burst stimulation (iTBS) – an effective repetitive transcranial magnetic stimulation (rTMS) protocol for increasing cortical excitability – depends on network properties of the cortical motor system. We furthermore investigated whether the responsiveness to iTBS is dose-dependent.
To this end, we used a sham-stimulation controlled, single-blinded within-subject design testing for the relationship between iTBS aftereffects and (i) motor-evoked potentials (MEPs) as well as (ii) resting-state functional connectivity (rsFC) in 16 healthy subjects. In each session, three blocks of iTBS were applied, separated by 15min.
We found that non-responders (subjects not showing an MEP increase of ≥10% after one iTBS block) featured stronger rsFC between the stimulated primary motor cortex (M1) and premotor areas before stimulation compared to responders. However, only the group of responders showed increases in rsFC and MEPs, while most non-responders remained close to baseline levels after all three blocks of iTBS. Importantly, there was still a large amount of variability in both groups.
Our data suggest that responsiveness to iTBS at the local level (i.e., M1 excitability) depends upon the pre-interventional network connectivity of the stimulated region. Of note, increasing iTBS dose did not turn non-responders into responders. The finding that higher levels of pre-interventional connectivity precluded a response to iTBS could reflect a ceiling effect underlying non-responsiveness to iTBS at the systems level.
•Non-responders to iTBS feature stronger baseline premotor-M1 connectivity.•Responders show a lasting increase in MEPs and rsFC after multiple iTBS blocks.•Increasing the iTBS dose does not induce responsiveness.
Journal Article
The effect of SSRIs on unconditioned anxiety: a systematic review and meta-analysis of animal studies
by
Verdouw, P. Monika
,
Groenink, Lucianne
,
Bijlsma, Elisabeth Y
in
Animal research
,
Anxiety
,
Avoidance behavior
2024
RationaleSelective serotonin reuptake inhibitors (SSRIs) are the first choice of treatment for anxiety-like disorders. However, which aspects of anxiety are affected by SSRIs is not yet fully understood.ObjectiveWe aimed to systematically review the effect of six clinically effective SSRIs on four aspects of unconditioned anxiety: approach-avoidance behaviour (elevated plus maze), repetitive behaviour (marble burying), distress behaviour (ultrasonic vocalization), and activation of the autonomous nervous system (stress-induced hyperthermia).MethodsWe identified publications by searching Medline and Embase databases and assessed the risk of bias. A random effects meta-analysis was performed and moderator effects were analysed with Bayesian penalized meta-regression.ResultsOur search yielded 105 elevated plus maze, 63 marble burying, 11 ultrasonic vocalization, and 7 stress-induced hyperthermia articles. Meta-analysis suggested that SSRIs reduce anxiety-like behaviour in the elevated plus maze, marble burying and ultrasonic vocalization test and that effects are moderated by pre-existing stress conditions (elevated plus maze) and dose dependency (marble burying) but not by duration of treatment or type of SSRI. The reporting quality was low, publication bias was likely, and heterogeneity was high.ConclusionSSRIs seem to reduce a broad range of unconditioned anxiety-associated behaviours. These results should be interpreted with caution due to a high risk of bias, likely occurrence of publication bias, substantial heterogeneity and limited moderator data availability. Our review demonstrates the importance of including bias assessments when interpreting meta-analysis results. We further recommend improving the reporting quality, the conduct of animal research, and the publication of all results regardless of significance.
Journal Article
Visible light-responsive hydrogels for cellular dynamics and spatiotemporal viscoelastic regulation
2025
Viscoelastic heterogeneity of matrices plays a pivotal role in cancer cell spreading, migration, and metastasis. However, the creation of viscoelastic platforms with spatial-temporal regulation is hindered by cytotoxicity and short regulation durations. Our research presents a dual mechanism for stress relaxation regulation- both intrinsic and responsive- by incorporating Schiff base bonds and a visible light-responsive thiuram disulfide (TDS) moiety into the hydrogel. Modifying base bonds facilitates a broad spectrum of intrinsic stress relaxation times. At the same time, incorporating the visible light-responsive TDS moiety endows the hydrogel with responsive viscoelastic properties. These properties are characterized by minimal cytotoxicity, spatial-temporal controllability, dose dependency, and reversibility. Utilizing this platform, we demonstrate that ovarian cancer cells exhibit contrasting behaviors in contraction and spreading when subjected to dynamic stress relaxation changes over various time periods. Additionally, we observed a “memory effect” in the cell’s response to alterations in stress relaxation time. We can spatially direct cell migration through viscoelastic heterogeneity, achieved via photopatterning substrates and laser spots. This innovative approach provides a means to regulate the viscoelasticity of hydrogels across a wide range of timescales, thereby opening avenues for more advanced studies into how cells interpret and respond to spatiotemporal viscoelastic signals.
The viscoelastic properties of a matrix influence the behaviour of cancer cells, but platforms with the required spatial and temporal control over properties is challenging. Here, the authors report a hydrogel combining Schiff base and thiuram disulfide groups for light responsive behaviour and varying stress relaxation.
Journal Article