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1.
Phys Rev Lett ; 132(10): 101802, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38518308

RESUMO

We reexamine the low-energy potential for a macroscopic fifth force generated from the exchange of two axions. The shift symmetry of the linear axion interactions leads to a potential falling off as V(r)∼1/r^{5}. We find that in the case of the QCD axion higher-order terms in the Lagrangian break the shift symmetry and lead to the dominant contribution to the potential scaling as V(r)∼1/r^{3}. These terms are generated by the same physics responsible for the axion mass, and therefore the new contributions to the potential induce a different force for external nucleons and leptons. We demonstrate how this result affects the sensitivity of searches for new long-range forces.

2.
J Child Psychol Psychiatry ; 65(1): 31-41, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37402634

RESUMO

BACKGROUND: Childhood maltreatment is associated with pervasive risk for depression. However, the immediate cognitive and neural mechanisms that mediate this risk during development are unknown. We here studied the impact of maltreatment on self-generated thought (SGT) patterns and their association with depressive symptoms, subcallosal cingulate cortex (SCC) thickness, and cortisol levels in children. METHODS: We recruited 183 children aged 6-12 years, 96 of which were exposed to maltreatment. Children performed a mind wandering task to elicit SGTs. A subgroup of children underwent structural magnetic resonance imaging (N = 155) for SCC thickness analyses and saliva collection for quantification of free cortisol concentrations (N = 126) was collected. Using network analysis, we assessed thought networks and compared these networks between children with and without maltreatment exposure. Using multilevel analyses, we then tested the association between thought networks of children with maltreatment exposure with depressive symptoms, SCC thickness, and cortisol levels. RESULTS: Children exposed to maltreatment generated fewer positively valenced thoughts. Network analysis revealed rumination-like thought patterns in children with maltreatment exposure, which were associated with depressive symptoms, SCC thickness, and cortisol levels. Children with maltreatment exposure further exhibited decreased future-self thought coupling, which was associated with depressive symptoms, while other-related and past-oriented thoughts had the greatest importance within the network. CONCLUSIONS: Using a novel network analytic approach, we provide evidence that children exposed to maltreatment exhibit ruminative clustering of thoughts, which is associated with depressive symptoms and neurobiological correlates of depression. Our results provide a specific target for clinical translation to design early interventions for middle childhood. Targeting thought patterns in children with maltreatment exposure may be an effective strategy to effectively mitigate depression risk early in life.


Assuntos
Maus-Tratos Infantis , Depressão , Humanos , Criança , Depressão/psicologia , Hidrocortisona , Giro do Cíngulo/diagnóstico por imagem , Maus-Tratos Infantis/psicologia
3.
Br J Clin Pharmacol ; 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39428980

RESUMO

AIMS: Clomipramine (CLOMI) has shown effectiveness in treating premature ejaculation but is linked to erectile dysfunction and reduced libido. Yohimbine (YOH), by contrast, is effective in treating erectile dysfunction and may improve libido. Combining CLOMI and YOH could potentially leverage the benefits of both drugs. This study aimed to investigate the interactions between these drugs and to evaluate their safety profile. METHODS: A prospective, open-labelled, single-centre, pharmacokinetic (PK) drug-drug interaction study was performed in 15 healthy male subjects. Single-dose and steady-state PK were investigated using noncompartmental analysis after mono- and combination therapy of the 2 orally applied drugs. Plasma sampling was performed at baseline, 0.5 (YOH), 1, 1.5 (YOH), 2, 3, 4, 5, 6, 8, 12 and 24 h (CLOMI). Differences in the area under the curve after multiple dosing (MD) were determined using an equivalence boundary of 80-125%. RESULTS: The geometric mean ratio of the area under the curve up to 12 h for MD CLOMI (combination vs. monotherapy) was 112% (90% confidence interval: 104-120%), whereas for MD YOH this ratio was 137% (90% confidence interval: 112-168%). The study drugs were safe and well tolerated as mono- and combination therapy, with no major adverse events reported. CONCLUSION: A PK assessment of clomipramine and yohimbine indicated a clinically significant drug-drug interaction for MD YOH in combination with CLOMI. This might be explained by competitive, CLOMI-related inhibition of YOH metabolism, probably mediated by cytochrome P450 2D6. However, according to European Medicines Agency guidelines, the effect can be classified as interaction absent (<1,25 fold) or minor (>1.25-<2-fold). Given the complimentary mechanisms of action and the favourable safety profiles, the findings pave the way for future efficacy studies.

4.
Healthc Manage Forum ; 37(6): 423-428, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39120578

RESUMO

This article investigates whether, in the context of rising nationalism, drawing attention to national innovation strategies influences public health behaviours, particularly vaccine uptake. It draws on an original two-wave panel study of United Kingdom (UK) respondents during the COVID pandemic. The survey included an experimental design, which primed respondents with a nationalist framing of COVID-19 vaccines, drawing attention to the UK's role in developing the AstraZeneca vaccine and in rapid approval and roll out of other vaccines. Our results show no significant impact of nationalist framing on vaccine willingness, even among those with nationalist or science-skeptical views. These findings suggest public health authorities should be cautious with nationalist framing, as it may be ineffective or counterproductive.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Reino Unido , COVID-19/prevenção & controle , COVID-19/epidemiologia , Vacinas contra COVID-19/administração & dosagem , Saúde Pública , Inquéritos e Questionários , Comportamentos Relacionados com a Saúde , Pandemias , Masculino , Feminino , Adulto , Pessoa de Meia-Idade
5.
J Neurosci ; 42(46): 8658-8669, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36195439

RESUMO

Neurons in the gustatory cortex (GC) represent taste through time-varying changes in their spiking activity. The predominant view is that the neural firing rate represents the sole unit of taste information. It is currently not known whether the phase of spikes relative to lick timing is used by GC neurons for taste encoding. To address this question, we recorded spiking activity from >500 single GC neurons in male and female mice permitted to freely lick to receive four liquid gustatory stimuli and water. We developed a set of data analysis tools to determine the ability of GC neurons to discriminate gustatory information and then to quantify the degree to which this information exists in the spike rate versus the spike timing or phase relative to licks. These tools include machine learning algorithms for classification of spike trains and methods from geometric shape and functional data analysis. Our results show that while GC neurons primarily encode taste information using a rate code, the timing of spikes is also an important factor in taste discrimination. A further finding is that taste discrimination using spike timing is improved when the timing of licks is considered in the analysis. That is, the interlick phase of spiking provides more information than the absolute spike timing itself. Overall, our analysis demonstrates that the ability of GC neurons to distinguish among tastes is best when spike rate and timing is interpreted relative to the timing of licks.SIGNIFICANCE STATEMENT Neurons represent information from the outside world via changes in their number of action potentials (spikes) over time. This study examines how neurons in the mouse gustatory cortex (GC) encode taste information when gustatory stimuli are experienced through the active process of licking. We use electrophysiological recordings and data analysis tools to evaluate the ability of GC neurons to distinguish tastants and then to quantify the degree to which this information exists in the spike rate versus the spike timing relative to licks. We show that the neuron's ability to distinguish between tastes is higher when spike rate and timing are interpreted relative to the timing of licks, indicating that the lick cycle is a key factor for taste processing.


Assuntos
Percepção Gustatória , Paladar , Masculino , Feminino , Camundongos , Animais , Paladar/fisiologia , Percepção Gustatória/fisiologia , Potenciais de Ação/fisiologia , Neurônios/fisiologia , Comportamento Animal
6.
Rep Prog Phys ; 86(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36279851

RESUMO

Rare meson decays are among the most sensitive probes of both heavy and light new physics. Among them, new physics searches using kaons benefit from their small total decay widths and the availability of very large datasets. On the other hand, useful complementary information is provided by hyperon decay measurements. We summarize the relevant phenomenological models and the status of the searches in a comprehensive list of kaon and hyperon decay channels. We identify new search strategies for under-explored signatures, and demonstrate that the improved sensitivities from current and next-generation experiments could lead to a qualitative leap in the exploration of light dark sectors.

7.
Antimicrob Agents Chemother ; 67(3): e0149322, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36786609

RESUMO

Transporter-mediated drug-drug interactions (DDIs) are of concern in antimicrobial drug development, as they can have serious safety consequences. We used positron emission tomography (PET) imaging-based pharmacokinetic (PK) analysis to assess the effect of different drugs, which may cause transporter-mediated DDIs, on the tissue distribution and excretion of [18F]ciprofloxacin as a radiolabeled model antimicrobial drug. Mice underwent PET scans after intravenous injection of [18F]ciprofloxacin, without and with pretreatment with either probenecid (150 mg/kg), cimetidine (50 mg/kg), or pyrimethamine (5 mg/kg). A 3-compartment kidney PK model was used to assess the involvement of renal transporters in the examined DDIs. Pretreatment with probenecid and cimetidine significantly decreased the renal clearance (CLrenal) of [18F]ciprofloxacin. The effect of cimetidine (-86%) was greater than that of probenecid (-63%), which contrasted with previously published clinical data. The kidney PK model revealed that the decrease in CLrenal was caused by inhibition of basal uptake transporters and apical efflux transporters in kidney proximal tubule cells. Changes in the urinary excretion of [18F]ciprofloxacin after pretreatment with probenecid and cimetidine resulted in increased blood and organ exposure to [18F]ciprofloxacin. Our results suggest that multiple membrane transporters mediate the tubular secretion of ciprofloxacin, with possible species differences between mice and humans. Concomitant medication inhibiting renal transporters may precipitate DDIs, leading to decreased urinary excretion and increased blood and organ exposure to ciprofloxacin, potentially exacerbating adverse effects. Our study highlights the strength of PET imaging-based PK analysis to assess transporter-mediated DDIs at a whole-body level.


Assuntos
Anti-Infecciosos , Probenecid , Humanos , Camundongos , Animais , Probenecid/farmacologia , Cimetidina/farmacologia , Rim/diagnóstico por imagem , Proteínas de Membrana Transportadoras , Interações Medicamentosas , Tomografia por Emissão de Pósitrons , Ciprofloxacina/farmacocinética
8.
J Antimicrob Chemother ; 78(2): 380-388, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36433819

RESUMO

BACKGROUND: High protein binding (PB) of antibiotics has an impact on their antimicrobial activity. It has been questioned whether in vitro PB determination can capture the dynamic and concentration-dependent PB of highly bound antibiotics. OBJECTIVES: This clinical study compared in vitro ultrafiltration (UF) and in vivo IV microdialysis (MD) methods to determine ceftriaxone PB. METHODS: Six healthy male volunteers received a single IV 2 g dose of ceftriaxone. Unbound ceftriaxone plasma concentrations were measured with MD and venous plasma sampling with subsequent UF. Pharmacokinetic parameters were determined using non-compartmental pharmacokinetic analysis. Non-linear mixed-effects modelling was used to quantify the PB. The PTA was estimated. RESULTS: The Cmax of ceftriaxone total plasma concentration (297.42 ±â€Š21.0 mg/L) was approximately 5.5-fold higher than for free concentrations obtained with UF (52.83 ±â€Š5.07 mg/L), and only 3.5-fold higher than for free concentrations obtained with MD (81.37 ±â€Š26.93 mg/L). Non-linear, saturable PB binding was confirmed for both UF and MD. Significantly different dissociation constants (Kd) for the albumin/ceftriaxone complex were quantified: in UF it was 23.7 mg/L (95% CI 21.3-26.2) versus 15.9 mg/L (95% CI 13.6-18.6) in MD. Moreover, the estimated number of binding sites (95% CI) per albumin molecule was 0.916 (0.86-0.97) in UF versus 0.548 in MD (0.51-0.59). The PTA obtained with MD was at most 27% higher than with UF. CONCLUSIONS: In vitro UF versus in vivo intravasal MD revealed significantly different PB, especially during the distribution phase. The method of PB determination could have an impact on the breakpoint determination and dose optimisation of antibiotics.


Assuntos
Ceftriaxona , Ultrafiltração , Humanos , Masculino , Ceftriaxona/farmacocinética , Ligação Proteica , Ultrafiltração/métodos , Microdiálise , Antibacterianos/uso terapêutico , Albuminas
9.
Mol Pharm ; 20(11): 5877-5887, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37883694

RESUMO

P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) are two ATP-binding cassette efflux transporters that are coexpressed at the human blood-brain barrier (BBB) and blood-retina barrier (BRB). While pharmacological inhibition of P-gp and/or BCRP results in increased brain distribution of dual P-gp/BCRP substrate drugs, such as the tyrosine kinase inhibitor erlotinib, the effect of P-gp and/or BCRP inhibition on the retinal distribution of such drugs has hardly been investigated. In this study, we used positron emission tomography (PET) imaging to assess the effect of transporter inhibition on the distribution of [11C]erlotinib to the human retina and brain. Twenty two healthy volunteers underwent two PET scans after intravenous (i.v.) injection of a microdose (<5 µg) of [11C]erlotinib, a baseline scan, and a second scan either with concurrent i.v. infusion of tariquidar to inhibit P-gp (n = 5) or after oral intake of single ascending doses of erlotinib (300 mg, 650 mg, or 1000 mg, n = 17) to saturate erlotinib transport. In addition, transport of [3H]erlotinib to the retina and brain was assessed in mice by in situ carotid perfusion under various drug transporter inhibition settings. In comparison to the baseline PET scan, coadministration of tariquidar or erlotinib led to a significant decrease of [11C]erlotinib total volume of distribution (VT) in the human retina by -25 ± 8% (p ≤ 0.05) and -41 ± 16% (p ≤ 0.001), respectively. In contrast, erlotinib intake led to a significant increase in [11C]erlotinib VT in the human brain (+20 ± 16%, p ≤ 0.001), while administration of tariquidar did not result in any significant changes. In situ carotid perfusion experiments showed that both P-gp and BCRP significantly limit the distribution of erlotinib to the mouse retina and brain but revealed a similar discordant effect at the mouse BRB and BBB following co-perfusion with tariquidar and erlotinib as in humans. Co-perfusion with prototypical inhibitors of solute carrier transporters did not reveal a significant contribution of organic cation transporters (e.g., OCTs and OCTNs) and organic anion-transporting polypeptides (e.g., OATP2B1) to the retinal and cerebral distribution of erlotinib. In conclusion, we observed a dissimilar effect after P-gp and/or BCRP inhibition on the retinal and cerebral distribution of [11C]erlotinib. The exact mechanism for this discrepancy remains unclear but may be related to the function of an unidentified erlotinib uptake carrier sensitive to tariquidar inhibition at the BRB. Our study highlights the great potential of PET to study drug distribution to the human retina and to assess the functional impact of membrane transporters on ocular drug distribution.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Neoplasias da Mama , Humanos , Camundongos , Animais , Feminino , Cloridrato de Erlotinib , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Neoplasias/metabolismo , Encéfalo/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Barreira Hematoencefálica/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Barreira Hematorretiniana/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Neoplasias da Mama/metabolismo
10.
Br J Clin Pharmacol ; 89(1): 416-420, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36223278

RESUMO

The effects of the human endotoxin challenge on tissue pharmacokinetics are unknown. In the present study, we aimed to assess the effect of the endotoxin challenge on interstitial fluid pharmacokinetics of tedizolid in healthy volunteers using intramuscular microdialysis. Eight healthy male subjects were treated with 200 mg of tedizolid phosphate for 6 days. On Day 6, an intravenous bolus of lipopolysaccharide (LPS) (2 ng/kg body weight) was administered. LPS infusion did not affect plasma pharmacokinetics of tedizolid. In contrast, following LPS infusion, median muscle tissue fAUC (0.83 [0.75-1.15] vs. 1.14 [1.11-1.43] mg × h/L, P = .0078) and muscle tissue fCmax (0.15 [0.14-0.19] vs. 0.19 [0.18-0.24] mg/L, P = .0078) were significantly increased by 38% and 24%, respectively. The human endotoxin challenge was associated with increased tissue concentrations of tedizolid, without affecting its plasma concentration-time profile. The human endotoxin challenge combined with microdialysis may be used to investigate the influence of systemic inflammation on tissue pharmacokinetics.


Assuntos
Antibacterianos , Oxazolidinonas , Humanos , Masculino , Endotoxinas , Lipopolissacarídeos , Oxazolidinonas/farmacocinética
12.
Int J Comput Vis ; 131(5): 1183-1209, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37069835

RESUMO

This paper introduces a set of numerical methods for Riemannian shape analysis of 3D surfaces within the setting of invariant (elastic) second-order Sobolev metrics. More specifically, we address the computation of geodesics and geodesic distances between parametrized or unparametrized immersed surfaces represented as 3D meshes. Building on this, we develop tools for the statistical shape analysis of sets of surfaces, including methods for estimating Karcher means and performing tangent PCA on shape populations, and for computing parallel transport along paths of surfaces. Our proposed approach fundamentally relies on a relaxed variational formulation for the geodesic matching problem via the use of varifold fidelity terms, which enable us to enforce reparametrization independence when computing geodesics between unparametrized surfaces, while also yielding versatile algorithms that allow us to compare surfaces with varying sampling or mesh structures. Importantly, we demonstrate how our relaxed variational framework can be extended to tackle partially observed data. The different benefits of our numerical pipeline are illustrated over various examples, synthetic and real. Supplementary Information: The online version contains supplementary material available at 10.1007/s11263-022-01743-0.

13.
J Antimicrob Chemother ; 77(11): 3086-3092, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36039038

RESUMO

OBJECTIVES: The efficacy and quality of generic antibacterial drug formulations are often questioned by both healthcare specialists and patients. Therefore, the present study investigated the interchangeability of generic drugs with their originators by comparing bioequivalence parameters and stability data of generic cefepime, linezolid and piperacillin/tazobactam with their respective originator drugs. METHODS: In this open-label, randomized, crossover bioequivalence study, three groups of 12 healthy volunteers each received a single intravenous infusion of either 2 g of cefepime or 4.5 g of piperacillin/tazobactam and two generic formulations, or 600 mg of linezolid and one generic formulation. Plasma sampling was performed, with a 5 day washout period between study days. Stability was tested by storing reconstituted generic and originator products according to their own storage specifications and those of the comparator products. All concentrations were measured by LC-MS. RESULTS: Similar ratios of generic/originator (90% CI) Cmax were observed for Cefepime-MIP/Maxipime [93.7 (88.4-99.4)], Cefepime Sandoz/Maxipime [95.9 (89.1-103.2)], Linezolid Kabi/Zyvoxid [104.5 (91.1-119.9)], Piperacillin Kabi/Tazobac [95.9 (90.4-101.7)], Piperacillin Aurobindo/Tazobac [99.7 (84.9-104.7)], Tazobactam Kabi/Tazobac [93.4 (87.4-99.8)] and Tazobactam Aurobindo/Tazobac [97.4 (89.7-105.8)]. Accordingly, similar ratios of AUC0-t were observed for Cefepime-MIP/Maxipime [91.1 (87.6-94.8)], Cefepime Sandoz/Maxipime [97.9 (92.5-103.5)], Linezolid Kabi/Zyvoxid [99.7 (93.3-106.6)], Piperacillin Kabi/Tazobac [92.2 (88.3-96.3)], Piperacillin Aurobindo/Tazobac [99.9 (97.0-102.8)], Tazobactam Kabi/Tazobac [91.4 (86.4-96.7)] and Tazobactam Aurobindo/Tazobac [98.8 (94.3-103.6)]. Stable and similar concentrations were measured for all contiguous substances, regardless of storage conditions. CONCLUSIONS: Compared with their respective originator drugs, generic cefepime, linezolid and piperacillin/tazobactam met the predetermined bioequivalence criteria. All formulations were stable under the storage conditions of their respective comparators.


Assuntos
Medicamentos Genéricos , Piperacilina , Humanos , Cefepima , Linezolida , Equivalência Terapêutica , Voluntários Saudáveis , Combinação Piperacilina e Tazobactam , Piperacilina/uso terapêutico , Tazobactam , Antibacterianos/uso terapêutico , Ácido Penicilânico/uso terapêutico
14.
J Antimicrob Chemother ; 77(5): 1424-1431, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35165727

RESUMO

BACKGROUND: Preclinical data suggested anti-inflammatory properties of tedizolid. OBJECTIVES: To investigate the influence of tedizolid on the cytokine response to the human endotoxin challenge and the effect of endotoxaemia on the pharmacokinetics and protein binding of tedizolid. METHODS: In this cross-over trial, 14 male healthy volunteers underwent two treatment periods: (A) 200 mg of tedizolid phosphate once daily for 6 days (3 days orally and 3 days intravenously), followed by an intravenous bolus of 2 ng/kg body weight of LPS on the last treatment day; and (B) intravenous bolus of LPS (2 ng/kg body weight) without concomitant tedizolid treatment. Participants underwent first period A or B, separated by at least 6 weeks. Plasma was sampled to assess cytokines and the pharmacokinetics of tedizolid. RESULTS: Following the endotoxin challenge, the peak plasma concentration (median [IQR]; 280 [155-502] versus 287 [132-541]  pg/mL; P = 0.875) and AUC0-24 (979 [676-1319] versus 1000 [647-1632]  pg·h/mL; P = 0.638) of interleukin-6 remained unchanged with and without concomitant tedizolid treatment. The peak concentration and AUC0-24 of TNF-α remained also unchanged with and without tedizolid (47 [31-61] versus 54 [27-69]  pg/mL; P = 0.73 and 197 [163-268] versus 234 [146-280]  pg·h/mL; P = 0.875, respectively). The total maximum concentration (mean ± SD; 2.94 ± 0.69 versus 2.96 ± 0.62 mg/L), total AUC0-24 (22.3 ± 3.8 versus 21.1 ± 3.6 mg·h/L) and protein binding (21.4% ± 1.7% versus 21.6% ± 1.9%) of tedizolid were similar with and without the endotoxin challenge. CONCLUSIONS: Tedizolid did not attenuate the LPS-induced cytokine response in healthy volunteers. Furthermore, endotoxaemia did not influence the plasma pharmacokinetics of tedizolid.


Assuntos
Endotoxemia , Endotoxinas , Antibacterianos , Peso Corporal , Estudos Cross-Over , Citocinas , Feminino , Voluntários Saudáveis , Humanos , Lipopolissacarídeos , Masculino , Oxazolidinonas , Tetrazóis
15.
Phys Rev Lett ; 129(17): 171801, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36332256

RESUMO

Extensions of the standard model of particle physics with new Abelian gauge groups allow for kinetic mixing between the new gauge bosons and the hypercharge gauge boson, resulting in mixing with the photon. In many models, the mixing with the hypercharge gauge boson captures only part of the kinetic mixing term with the photon, since the new gauge bosons can also mix with the neutral component of the SU(2)_{L} gauge bosons. We take these contributions into account and present a consistent description of kinetic mixing for general Abelian gauge groups both in the electroweak symmetric and the broken phase. We identify an effective operator that captures the kinetic mixing with SU(2)_{L} and demonstrate how renormalizable contributions arise if the charged fields only obtain their masses from electroweak symmetry breaking. For the first time, a low-energy theorem for the couplings of novel Abelian gauge bosons with the standard model Higgs boson is derived from the one-loop kinetic mixing amplitudes.

16.
Environ Sci Technol ; 56(10): 6360-6368, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35507770

RESUMO

Transport, transformation, and removal of iron in aqueous environments is primarily controlled by ferrous iron oxidation followed by aggregation and sedimentation of the resultant hydrous ferric oxides. The latter mechanisms are particularly important for passive iron removal in mine water treatment systems, yet the interrelation and underlying kinetics are poorly understood. In this study, the sedimentation behavior of natural hydrous ferric oxides was systematically investigated under different hydrogeochemical conditions via laboratory-based column experiments. The objective was to determine a robust model approach for the approximation of aggregation/sedimentation kinetics in engineered systems. The results showed that sedimentation is governed by two interrelated regimes, a rapid second-order aggregation-driven step (r1) at high iron levels followed by a slower first-order settling step (r2) at lower iron levels. A mixed first-/second-order model was found to adequately describe the process: -d[Fe]dt=kr2[Fe]+kr1[Fe]2 with kr1 = 9.4 × 10-3 m3/g/h and kr2 = 5.4 × 10-3 h-1. Moreover, we were able to demonstrate that the removal of particulate hydrous ferric oxides at low particulate iron levels (<10 mg/L) may be reasonably well approximated by a simplified first-order relationship: -d[Fe]dt=ksed[Fe] with ksed = 2.4 (±0.4) × 10-2 h-1, which agrees well with incipient literature estimates. Only minor effects of pH, salinity, and mineralogy on kinetic parameters were observed. Hence, the results of this study may be broadly transferrable among different mine sites.


Assuntos
Compostos Férricos , Purificação da Água , Ferro , Cinética , Minerais , Oxirredução , Óxidos , Purificação da Água/métodos
17.
Anesth Analg ; 134(5): 974-986, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34889805

RESUMO

BACKGROUND: Chronic posttraumatic/postsurgical pain (CPSP) is common after traumatic or surgical damage. Exposure to both trauma and surgery, with the potential for repeated bone and nerve damage, may increase the risk of CPSP after fracture-related surgery. But the (long-term) incidences of CPSP and neuropathic CPSP and the ensuing burdens are unknown. Therefore, the patients were prospectively assessed within 1 year, and the patient-specific characteristics were explored. METHODS: Between 2017 and 2018, 127 patients (age: 52.9 ± 17.1 years, male: 55.1%) with traumatic fractures needing osteosynthesis (extremities: 91.3%) were assessed posttrauma (before surgery), postsurgery at days 1 to 5, 6 weeks, 3 and 12 months. The primary outcomes are as follows: incidence at 3 and 12 months of CPSP (defined as pain intensity on a numerical rating scale [NRS: 0-10] ≥3), secondary exploration: neuropathic CPSP (NRS ≥3 and Douleur Neuropathique 4 interview [DN4i] score ≥3 [Douleur Neuropathique interview: 0-7]); burden: quality of life (QoL, the EuroQOL five dimensions questionnaire [EQ-5D-3L] descriptive system); and inter alia, the number of analgesics (trial registration: DRKS00011601). RESULTS: The incidence of CPSP was 57.1% (52/91, n/N) at 3 and 42.7% (35/82) at 12 months postsurgery, including neuropathic CPSP 7.7% (4/52) and 17.1% (6/35), respectively. Descriptively, posttraumatic higher pain intensity at rest (difference of 0.9 ± 1.8 NRS) and the need for more frequent analgesics (by 34.3%) were associated with CPSP a year after surgery compared to those without. As soon as week 6, these patients had developed descriptively a 15% more impaired QoL, with 25% more impairment after 1 year. The patients with CPSP presented with at least 1 neuropathic symptom 12 months later in 68.6% (24/35) of cases, mainly with an early posttraumatic occurrence (without fulfilling the definition of neuropathic CPSP). CONCLUSIONS: After early fracture-related surgery, high incidences of CPSP (43%) were prospectively observed 1 year postsurgery, up to approximately 1 in 5 patients who had neuropathic CPSP. At the same time, CPSP was accompanied with an impacted QoL and analgesic dependence, both indicating clinical relevance. Moreover, the high incidence and the early posttraumatic occurrence of more intense pain suggest that the initial fracture-related trauma, rather than the surgical trauma, may predominantly trigger CPSP at Y1 (1 year). Therefore, these exploratory results set the direction of required future research. A future clinical hypothesis might be: treat first what hurts first.


Assuntos
Dor Crônica , Fraturas Ósseas , Adulto , Idoso , Analgésicos , Dor Crônica/diagnóstico , Dor Crônica/epidemiologia , Dor Crônica/etiologia , Seguimentos , Fraturas Ósseas/complicações , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/efeitos adversos , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/etiologia , Qualidade de Vida
18.
Int J Mol Sci ; 23(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35742960

RESUMO

Multidrug resistance-associated protein 1 (MRP1, encoded by the ABCC1 gene) may contribute to the clearance of amyloid-beta (Aß) peptides from the brain into the blood and stimulation of MRP1 transport activity may be a therapeutic approach to enhance brain Aß clearance. In this study, we assessed the effect of thiethylperazine, an antiemetic drug which was shown to stimulate MRP1 activity in vitro and to decrease Aß load in a rapid ß-amyloidosis mouse model (APP/PS1-21), on MRP1 transport activity by means of positron emission tomography (PET) imaging with the MRP1 tracer 6-bromo-7-[11C]methylpurine. Groups of wild-type, APP/PS1-21 and Abcc1(-/-) mice underwent PET scans before and after a 5-day oral treatment period with thiethylperazine (15 mg/kg, once daily). The elimination rate constant of radioactivity (kelim) was calculated from time-activity curves in the brain and the lungs as a measure of tissue MRP1 activity. Treatment with thiethylperazine had no significant effect on MRP1 activity in the brain and the lungs of wild-type and APP/PS1-21 mice. This may either be related to a lack of an MRP1-stimulating effect of thiethylperazine in vivo or to other factors, such as substrate-dependent MRP1 stimulation, insufficient target tissue exposure to thiethylperazine or limited sensitivity of the PET tracer to measure MRP1 stimulation.


Assuntos
Doença de Alzheimer , Tietilperazina , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Presenilina-1/genética , Tietilperazina/metabolismo
19.
Phys Rev Lett ; 127(8): 081803, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34477407

RESUMO

We present a consistent implementation of weak decays involving an axion or axionlike particle in the context of an effective chiral Lagrangian. We argue that previous treatments of such processes have used an incorrect representation of the flavor-changing quark currents in the chiral theory. As an application, we derive model-independent results for the decays K^{-}→π^{-}a and π^{-}→e^{-}ν[over ¯]_{e}a at leading order in the chiral expansion and for arbitrary axion couplings and mass. In particular, we find that the K^{-}→π^{-}a branching ratio is almost 40 times larger than previously estimated.

20.
Eur J Clin Pharmacol ; 77(10): 1473-1484, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33969434

RESUMO

PURPOSE: AT04A and AT06A are two AFFITOPE® peptide vaccine candidates being developed for the treatment of hypercholesterolemia by inducing proprotein convertase subtilisin/kexin type 9 (PCSK9)-specific antibodies. This study aimed to investigate safety, tolerability, antibody development, and reduction of low-density lipoprotein cholesterol (LDLc) following four subcutaneous immunizations. METHODS: This phase I, single-blind, randomized, placebo-controlled study was conducted in a total of 72 healthy subjects with a mean fasting LDLc level at baseline of 117.1 mg/dL (range 77-196 mg/dL). Each cohort enrolled 24 subjects to receive three priming immunizations at weeks 0, 4, and 8 and to receive a single booster immunization at week 60 of either AT04A, AT06A, or placebo. In addition to safety (primary objective), the antigenic peptide- and PCSK9-specific antibody response and the impact on LDLc were evaluated over a period of 90 weeks. RESULTS: The most common systemic treatment-related adverse events (AEs) reported were fatigue, headache, and myalgia in 75% of subjects in the AT06A group and 58% and 46% of subjects in the placebo and AT04A groups, respectively. Injection site reactions (ISR) representing 63% of all treatment-emergent adverse events (TEAEs), were transient and mostly of mild or moderate intensity and rarely severe (3%). Both active treatments triggered a robust, long-lasting antibody response towards the antigenic peptides used for immunization that optimally cross-reacted with the target epitope on PCSK9. In the AT04A group, a reduction in serum LDLc was observed with a mean peak reduction of 11.2% and 13.3% from baseline compared to placebo at week 20 and 70 respectively, and over the whole study period, the mean LDLc reduction for the AT04A group vs. placebo was -7.2% (95% CI [-10.4 to -3.9], P < 0.0001). In this group, PCSK9 target epitope titers above 50 were associated with clinically relevant LDLc reductions with an individual maximal decrease of 39%. CONCLUSIONS: Although both AT04A and AT06 were safe and immunogenic, only AT04A demonstrated significant LDLc-lowering activity, justifying further development. TRIAL REGISTRATION: EudraCT: 2015-001719-11. ClinicalTrials.gov Identifier: NCT02508896.


Assuntos
Hipercolesterolemia/tratamento farmacológico , Pró-Proteína Convertase 9/imunologia , Vacinas de Subunidades Antigênicas/uso terapêutico , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/efeitos adversos , Adulto Jovem
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