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1.
Phys Rev Lett ; 126(17): 172501, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33988438

RESUMO

In this Letter, we present a new expression for the overlaps of wave functions in Hartree-Fock-Bogoliubov based theories. Starting from the Pfaffian formula by Bertsch et al. [1], an exact and computationally stable formula for overlaps is derived. We illustrate the convenience of this new formulation with a numerical application in the context of the particle-number projection method. This new formula allows for substantially increased precision and versatility in chemical, atomic, and nuclear physics applications, particularly for methods dealing with superfluidity, symmetry restoration, and uses of nonorthogonal many-body basis states.

2.
Phys Rev Lett ; 126(3): 032503, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33543956

RESUMO

A nuclear spectroscopy experiment was conducted to study α-decay chains stemming from isotopes of flerovium (element Z=114). An upgraded TASISpec decay station was placed behind the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. The fusion-evaporation reactions ^{48}Ca+^{242}Pu and ^{48}Ca+^{244}Pu provided a total of 32 flerovium-candidate decay chains, of which two and eleven were firmly assigned to ^{286}Fl and ^{288}Fl, respectively. A prompt coincidence between a 9.60(1)-MeV α particle event and a 0.36(1)-MeV conversion electron marked the first observation of an excited state in an even-even isotope of the heaviest man-made elements, namely ^{282}Cn. Spectroscopy of ^{288}Fl decay chains fixed Q_{α}=10.06(1) MeV. In one case, a Q_{α}=9.46(1)-MeV decay from ^{284}Cn into ^{280}Ds was observed, with ^{280}Ds fissioning after only 518 µs. The impact of these findings, aggregated with existing data on decay chains of ^{286,288}Fl, on the size of an anticipated shell gap at proton number Z=114 is discussed in light of predictions from two beyond-mean-field calculations, which take into account triaxial deformation.

3.
Sci Rep ; 10(1): 5331, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32210327

RESUMO

Automated quantification of tissue morphology and tracer uptake in PET/MR images could streamline the analysis compared to traditional manual methods. To validate a single atlas image segmentation approach for automated assessment of tissue volume, fat content (FF) and glucose uptake (GU) from whole-body [18F]FDG-PET/MR images. Twelve subjects underwent whole-body [18F]FDG-PET/MRI during hyperinsulinemic-euglycemic clamp. Automated analysis of tissue volumes, FF and GU were achieved using image registration to a single atlas image with reference segmentations of 18 volume of interests (VOIs). Manual segmentations by an experienced radiologist were used as reference. Quantification accuracy was assessed with Dice scores, group comparisons and correlations. VOI Dice scores ranged from 0.93 to 0.32. Muscles, brain, VAT and liver showed the highest scores. Pancreas, large and small intestines demonstrated lower segmentation accuracy and poor correlations. Estimated tissue volumes differed significantly in 8 cases. Tissue FFs were often slightly but significantly overestimated. Satisfactory agreements were observed in most tissue GUs. Automated tissue identification and characterization using a single atlas segmentation performs well compared to manual segmentation in most tissues and will be valuable in future studies. In certain tissues, alternative quantification methods or improvements to the current approach is needed.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imagem Corporal Total/métodos , Idoso , Algoritmos , Fenômenos Bioquímicos , Encéfalo/fisiologia , Feminino , Fluordesoxiglucose F18 , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Fígado/fisiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos
4.
BJOG ; 126(4): 486-492, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30347490

RESUMO

OBJECTIVE: To investigate whether Roux-en-Y gastric bypass (RYGB) affects oral desogestrel (etonogestrel) pharmacokinetics. DESIGN: Single centre, open label, phase-2 pharmacokinetic study. SETTING: University hospital of Linköping, Sweden. POPULATION: Fourteen women with planned RYGB surgery were included; nine women aged 18-45 years using 75 micrograms desogestrel completed the study. METHODS: Steady-state etonogestrel pharmacokinetic (PK) parameters were measured on three occasions for each individual (at 8 ± 6 weeks before surgery, and at 12 ± 2 and 52 ± 2 weeks after surgery). Each patient served as her own control. On each occasion, serum samples were collected during a 24-hour period and etonogestrel concentrations were determined with ultra-performance liquid chromatography/tandem mass spectrometry. MAIN OUTCOME MEASURES: Area under the plasma concentration time curve of etonogestrel (AUC0-24 hours ). RESULTS: All women had significant postoperative weight loss. There were no significant differences in AUC0-24 hours , terminal half-lives (t½ ), time to peak serum concentrations (Tmax ), or apparent oral clearances of etonogestrel (CLoral ) before and after gastric bypass surgery on any occasion. Peak serum concentrations (Cmax ) increased after 52 ± 2 weeks compared with preoperative values (0.817 ng/ml versus 0.590 ng/ml, P = 0.024). CONCLUSION: To our knowledge, this is the first study to investigate the effects on desogestrel pharmacokinetics after RYGB. This study did not reveal any clinically significant changes in etonogestrel pharmacokinetics, suggesting that oral desogestrel may be used by women after RYGB surgery. The sample size was limited, however, and therefore the results should be interpreted cautiously. TWEETABLE ABSTRACT: The pharmacokinetics of oral desogestrel does not appear to change after gastric bypass surgery.


Assuntos
Anticoncepcionais Orais Sintéticos/farmacocinética , Desogestrel/farmacocinética , Derivação Gástrica , Obesidade/sangue , Adulto , Desogestrel/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/cirurgia , Período Pós-Operatório , Período Pré-Operatório , Fatores de Tempo , Adulto Jovem
5.
CPT Pharmacometrics Syst Pharmacol ; 6(7): 458-468, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28556607

RESUMO

In this study, we present the translational modeling used in the discovery of AZD1979, a melanin-concentrating hormone receptor 1 (MCHr1) antagonist aimed for treatment of obesity. The model quantitatively connects the relevant biomarkers and thereby closes the scaling path from rodent to man, as well as from dose to effect level. The complexity of individual modeling steps depends on the quality and quantity of data as well as the prior information; from semimechanistic body-composition models to standard linear regression. Key predictions are obtained by standard forward simulation (e.g., predicting effect from exposure), as well as non-parametric input estimation (e.g., predicting energy intake from longitudinal body-weight data), across species. The work illustrates how modeling integrates data from several species, fills critical gaps between biomarkers, and supports experimental design and human dose-prediction. We believe this approach can be of general interest for translation in the obesity field, and might inspire translational reasoning more broadly.


Assuntos
Fármacos Antiobesidade/administração & dosagem , Azetidinas/administração & dosagem , Modelos Biológicos , Obesidade/tratamento farmacológico , Oxidiazóis/administração & dosagem , Receptores do Hormônio Hipofisário/antagonistas & inibidores , Pesquisa Translacional Biomédica , Animais , Fármacos Antiobesidade/farmacocinética , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêutico , Azetidinas/farmacocinética , Azetidinas/farmacologia , Azetidinas/uso terapêutico , Biomarcadores/metabolismo , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Descoberta de Drogas , Ingestão de Energia/efeitos dos fármacos , Feminino , Humanos , Masculino , Camundongos , Obesidade/metabolismo , Oxidiazóis/farmacocinética , Oxidiazóis/farmacologia , Oxidiazóis/uso terapêutico , Ratos , Receptores do Hormônio Hipofisário/metabolismo , Projetos de Pesquisa
6.
Eur J Clin Microbiol Infect Dis ; 36(3): 553-563, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27815778

RESUMO

Patients in the intensive care unit (ICU) are at risk for suboptimal levels of ß-lactam antibiotics, possibly leading to poor efficacy. Our aim was to investigate whether the actual minimum inhibitory concentration (MIC) compared to the more commonly used arbitrary epidemiological cut-off values (ECOFFs) would affect target attainment in ICU patients on empirical treatment with broad-spectrum ß-lactam antibiotics and to identify risk factors for not reaching target. In a prospective, multicenter study, ICU patients ≥18 years old and treated with piperacillin/tazobactam, meropenem, or cefotaxime were included. Clinical and laboratory data were recorded. Serum trough antibiotic levels from three consecutive days were analyzed by liquid chromatography-mass spectrometry (LC-MS). The target was defined as the free trough concentration above the MIC (100% fT>MIC). MICECOFF was used as the target and, when available, the actual MIC (MICACTUAL) was applied. The median age of the patients was 70 years old, 52% (58/111) were males, and the median estimated glomerular filtration rate (eGFR) was 48.0 mL/min/1.73 m2. The rate of patients reaching 100% fT > MICACTUAL was higher (89%, 31/35) compared to the same patients using MICECOFF (60%, p = 0.002). In total, 55% (61/111) reached 100% fT > MICECOFF. Increased renal clearance was independently associated to not reaching 100% fT > MICECOFF. On repeated sampling, >77% of patients had stable serum drug levels around the MICECOFF. Serum concentrations of ß-lactam antibiotics vary extensively between ICU patients. The rate of patients not reaching target was markedly lower for the actual MIC than when the arbitrary MIC based on the ECOFF was used, which is important to consider in future studies.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , beta-Lactamas/administração & dosagem , beta-Lactamas/farmacocinética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Cromatografia Líquida , Feminino , Taxa de Filtração Glomerular , Humanos , Unidades de Terapia Intensiva , Masculino , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Prospectivos , Soro/química , Adulto Jovem , beta-Lactamas/farmacologia
7.
Water Res ; 88: 104-116, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26476681

RESUMO

A reduced model of a completely stirred-tank bioreactor coupled to a settling tank with recycle is analyzed in its steady states. In the reactor, the concentrations of one dominant particulate biomass and one soluble substrate component are modelled. While the biomass decay rate is assumed to be constant, growth kinetics can depend on both substrate and biomass concentrations, and optionally model substrate inhibition. Compressive and hindered settling phenomena are included using the Bürger-Diehl settler model, which consists of a partial differential equation. Steady-state solutions of this partial differential equation are obtained from an ordinary differential equation, making steady-state analysis of the entire plant difficult. A key result showing that the ordinary differential equation can be replaced with an approximate algebraic equation simplifies model analysis. This algebraic equation takes the location of the sludge-blanket during normal operation into account, allowing for the limiting flux capacity caused by compressive settling to easily be included in the steady-state mass balance equations for the entire plant system. This novel approach grants the possibility of more realistic solutions than other previously published reduced models, comprised of yet simpler settler assumptions. The steady-state concentrations, solids residence time, and the wastage flow ratio are functions of the recycle ratio. Solutions are shown for various growth kinetics; with different values of biomass decay rate, influent volumetric flow, and substrate concentration.


Assuntos
Reatores Biológicos , Modelos Teóricos , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Biomassa , Cinética , Purificação da Água/métodos
8.
Pharmacogenomics J ; 15(2): 165-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25245581

RESUMO

We investigated whether polymorphisms in the CYP2D6 and CYP2C19 genes influence the metabolic ratios and enantiomeric S/R ratios of venlafaxine (VEN) and its metabolites O-desmethylvenlafaxine (ODV), N-desmethylvenlafaxine (NDV) and N,O-didesmethylvenlafaxine (DDV) in blood from forensic autopsy cases. In all, 94 postmortem cases found positive for VEN during toxicological screening were included. The CYP2D6 genotype was shown to significantly influence the ODV/VEN (P=0.003), DDV/NDV (P=0.010) and DDV/ODV (P=0.034) ratios. The DDV/ODV (P=0.013) and DDV/VEN (P=0.021) ratios were significantly influenced by the CYP2C19 genotype. The S/R ratios of VEN were significantly influenced by both CYP2D6 and CYP2C19 genotypes. CYP2D6 poor metabolizers (PMs) had lower S/R VEN ratios and CYP2C19 PMs had high S/R ratios of VEN in comparison. Our results show that the CYP2D6 genotype influences the O-demethylation whereas CYP2C19 influences the N-demethylation of VEN and its metabolites. In addition, we show a stereoselective metabolism where CYP2D6 favours the R-enantiomer whereas CYP2C19 favours the S-enantiomer.


Assuntos
Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2D6/genética , Polimorfismo Genético/genética , Cloridrato de Venlafaxina/metabolismo , Autopsia/métodos , Feminino , Ciências Forenses , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
9.
Water Sci Technol ; 69(7): 1373-85, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24718326

RESUMO

Key developments of instrumentation, control and automation (ICA) applications in wastewater systems during the past 40 years are highlighted in this paper. From the first ICA conference in 1973 through to today there has been a tremendous increase in the understanding of the processes, instrumentation, computer systems and control theory. However, many developments have not been addressed here, such as sewer control, drinking water treatment and water distribution control. It is hoped that this review can stimulate new attempts to more effectively apply control and automation in water systems in the coming years.


Assuntos
Automação/história , Gerenciamento de Resíduos/história , História do Século XX , História do Século XXI , Londres , Águas Residuárias
10.
Water Sci Technol ; 69(7): 1573-80, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24718353

RESUMO

Three large wastewater treatment plants in Sweden participate in a project evaluating different types of ammonium feedback controllers in full-scale operation. The goal is to improve process monitoring, maintain effluent water quality and save energy. The paper presents the outcome of the long-term evaluation of controllers. Based on the experiences gained from the full-scale implementations, a discussion is provided about energy assessment for the purpose of comparing control strategies. The most important conclusions are the importance of long-term experiments and the difficulty of comparing energy consumption based on air flow rate measurements.


Assuntos
Compostos de Amônio/química , Conservação de Recursos Energéticos , Retroalimentação , Gerenciamento de Resíduos , Suécia
11.
Phys Rev Lett ; 113(26): 262504, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25615316

RESUMO

We optimize chiral interactions at next-to-next-to leading order to observables in two- and three-nucleon systems and compute Gamow-Teller transitions in 14C and (22,24)O using consistent two-body currents. We compute spectra of the daughter nuclei 14N and (22,24)F via an isospin-breaking coupled-cluster technique, with several predictions. The two-body currents reduce the Ikeda sum rule, corresponding to a quenching factor q2≈0.84-0.92 of the axial-vector coupling. The half-life of 14C depends on the energy of the first excited 1+ state, the three-nucleon force, and the two-body current.

12.
Phys Rev Lett ; 113(25): 252501, 2014 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-25554877

RESUMO

We address the question of how to improve the agreement between theoretical nuclear single-particle energies (SPEs) and observations. Empirically, in doubly magic nuclei, the SPEs can be deduced from spectroscopic properties of odd nuclei that have one more or one less neutron or proton. Theoretically, bare SPEs, before being confronted with observations, must be corrected for the effects of the particle vibration coupling (PVC). In the present work, we determine the PVC corrections in a fully self-consistent way. Then, we adjust the SPEs, with PVC corrections included, to empirical data. In this way, the agreement with observations, on average, improves; nevertheless, large discrepancies still remain. We conclude that the main source of disagreement is still in the underlying mean fields, and not in including or neglecting the PVC corrections.

13.
Phys Rev Lett ; 111(11): 112502, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-24074079

RESUMO

A high-resolution α, x-ray, and γ-ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum für Schwerionenforschung. Thirty correlated α-decay chains were detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chains to originate from element Z=115. For the first time, precise spectroscopy allows the derivation of excitation schemes of isotopes along the decay chains starting with elements Z>112. Comprehensive Monte Carlo simulations accompany the data analysis. Nuclear structure models provide a first level interpretation.

14.
Water Sci Technol ; 68(3): 641-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23925193

RESUMO

Ammonium feedback control is increasingly used to determine the dissolved oxygen (DO) set-point in aerated activated sludge processes for nitrogen removal. This study compares proportional-integral (PI) ammonium feedback control with a DO profile created from a mathematical minimisation of the daily air flow rate. All simulated scenarios are set to reach the same treatment level of ammonium, based on a daily average concentration. The influent includes daily variations only and the model has three aerated zones. Comparisons are made at different plant loads and DO concentrations, and the placement of the ammonium sensor is investigated. The results show that ammonium PI control can achieve the best performance if the DO set-point is limited at a maximum value and with little integral action in the controller. Compared with constant DO control the best-performing ammonium controller can achieve 1-3.5% savings in the air flow rate, while the optimal solution can achieve a 3-7% saving. Energy savings are larger when operating at higher DO concentrations.


Assuntos
Oxigênio/química , Compostos de Amônio Quaternário/química , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Reatores Biológicos , Simulação por Computador , Retroalimentação , Modelos Químicos , Nitrificação , Oxigênio/análise
15.
Eur J Vasc Endovasc Surg ; 46(2): 214-22, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23770264

RESUMO

OBJECTIVE/BACKGROUND: Patients with peripheral arterial occlusive disease (PAOD), in particular critical limb ischaemia (CLI), carry a high risk of thrombotic events. We hypothesised that patients undergoing conservative, endovascular, or open surgical treatment for CLI have increased levels of plasminogen activator inhibitor-1 (PAI-1), leading to a prothrombotic state. The objective was to determine levels of PAI-1 in patients with acute or chronic PAOD/CLI. METHODS: Thirty-two patients with a median age of 74 (49-90) years were included. Three underwent thrombolysis for acute limb-threatening ischaemia. Twenty-six patients with chronic ischaemia received endovascular (n = 20) or open (n = 6) surgical treatment. Three were treated conservatively. Biomarkers and ankle brachial index (ABI) were measured before and up to 1 month after intervention. Patency was studied with repeated duplex ultrasound. RESULTS: Ankle pressure and ABI improved after intervention (p < .001). C-reactive protein (CRP) increased from a median of 7.90 mg/L at baseline to 31.5 on day 1 (p < .001), 28.0 on day 6 (p < .001), and returned to baseline levels on day 30. PAI-1 antigen and activity decreased from day 6 and onwards post-intervention compared with baseline (p < .05). A great individual variability in PAI-1 antigen and activity was observed. Although most actively treated patients had normal PAI-1 activity, 11/29 (38%) were above that level of normality at baseline, 10/24 (42%) on day 1, 3/23 (13%) on day 6, and 5/27 (19%) on day 30 after intervention. CONCLUSION: Endovascular and open surgical treatment resulted in improved ankle pressure and ABI. The intervention was followed by a transient increase in CRP and a sustained reduction in PAI-1 levels and activity.


Assuntos
Procedimentos Endovasculares , Isquemia/terapia , Doença Arterial Periférica/terapia , Inibidor 1 de Ativador de Plasminogênio/sangue , Terapia Trombolítica , Procedimentos Cirúrgicos Vasculares , Idoso , Idoso de 80 Anos ou mais , Índice Tornozelo-Braço , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Estado Terminal , Regulação para Baixo , Feminino , Humanos , Isquemia/sangue , Isquemia/diagnóstico , Isquemia/etiologia , Isquemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/sangue , Doença Arterial Periférica/complicações , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/fisiopatologia , Valor Preditivo dos Testes , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Grau de Desobstrução Vascular
16.
Water Sci Technol ; 67(11): 2374-98, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23752368

RESUMO

This review covers automatic control of continuous aeration systems in municipal wastewater treatment plants. The review focuses on published research in the 21st century and describes research into various methods to decide and control the dissolved oxygen (DO) concentration and to control the aerobic volume with special focus on plants with nitrogen removal. Important aspects of control system implementation and success are discussed, together with a critical review of published research on the topic. With respect to DO control and determination, the strategies used for control span from modifications and developments of conventional control methods which have been explored since the 1970s, to advanced control such as model-based predictive and optimal controllers. The review is supplemented with a summary of comparisons between control strategies evaluated in full-scale, pilot-scale and in simulations.


Assuntos
Oxigênio/análise , Eliminação de Resíduos Líquidos/métodos , Aerobiose , Algoritmos , Modelos Teóricos
17.
Clin Exp Immunol ; 173(2): 310-22, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23607776

RESUMO

Adoptive transfer of regulatory T cells (T(regs)) has been proposed for use as a cellular therapy to induce transplantation tolerance. Preclinical data are encouraging, and clinical trials with T(reg) therapy are anticipated. In this study, we investigate different strategies for the isolation and expansion of CD4(+) CD25(high) CD127(low) T(regs) from uraemic patients. We use allogeneic dendritic cells (DCs) as feeder cells for the expansion and compare T(reg) preparations isolated by either fluorescence activated cell sorting (FACS) or magnetic activated cell sorting (MACS) that have been expanded subsequently with either mature or tolerogenic DCs. Expanded T(reg) preparations have been characterized by their purity, cytokine production and in-vitro suppressive ability. The results show that T(reg) preparations can be isolated from uraemic patients by both FACS and MACS. Also, the type of feeder cells used in the expansion affects both the purity and the functional properties of the T(reg) preparations. In particular, FACS-sorted T(reg) preparations expanded with mature DCs secrete more interleukin (IL)-10 and granzyme B than FACS-sorted T(reg) preparations expanded with tolerogenic DCs. This is a direct comparison between different isolation techniques and expansion protocols with T(regs) from uraemic patients that may guide future efforts to produce clinical-grade T(regs) for use in kidney transplantation.


Assuntos
Técnicas de Cultura de Células/métodos , Células Dendríticas/imunologia , Imunoterapia Adotiva/métodos , Nefropatias/imunologia , Linfócitos T Reguladores/imunologia , Antígenos CD4/metabolismo , Processos de Crescimento Celular , Separação Celular , Células Cultivadas , Citocinas/metabolismo , Citometria de Fluxo , Antígenos HLA/imunologia , Humanos , Terapia de Imunossupressão , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Nefropatias/terapia , Transplante de Rim , Guias de Prática Clínica como Assunto , Tolerância ao Transplante , Listas de Espera
18.
Int J Legal Med ; 127(3): 579-86, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23515680

RESUMO

P-glycoprotein (P-gp), encoded by the ABCB1/MDR1 gene, is a drug transporter at the blood-brain barrier. Several polymorphisms in the ABCB1 gene are known to affect the activity and/or expression of P-gp, thereby influencing the treatment response and toxicity of P-gp substrates like citalopram and venlafaxine. In this study, we aimed to investigate the frequency of ABCB1 genotypes in forensic autopsy cases involving these two antidepressants. Further, the distribution of ABCB1 genotypes in deaths related to intoxication was compared to cases not associated to drug intoxication. The study included 228 forensic autopsy cases with different causes and manners of deaths. The ABCB1 single nucleotide polymorphisms (SNPs) G1199A, C1236T, C3435T and G2677T/A for these individuals were determined. The SNPs C1236T and C3435T in venlafaxine-positive cases were significantly different between the intoxication cases and non-intoxications. This was not seen for cases involving citalopram, indicating that the effect of genetic variants might be substrate specific. This novel finding should, however, be confirmed in future studies with larger number of cases.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Antidepressivos de Segunda Geração/intoxicação , Citalopram/intoxicação , Cicloexanóis/intoxicação , Overdose de Drogas/genética , Polimorfismo de Nucleotídeo Único , Subfamília B de Transportador de Cassetes de Ligação de ATP , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Autopsia , Estudos de Casos e Controles , Feminino , Genética Forense , Humanos , Masculino , Pessoa de Meia-Idade , Suécia , Cloridrato de Venlafaxina
19.
Water Res ; 46(7): 2101-10, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22341831

RESUMO

An important tool to minimise energy consumption in activated sludge processes is to control the aeration system. Aeration is a costly process and the dissolved oxygen level will determine the efficiency of the operation as well as the treatment results. What aeration control should achieve is closely linked to how the effluent criteria are defined. This paper explores how the aeration process should be controlled to meet the effluent discharge limits in an energy efficient manner in countries where the effluent nitrogen criterion is defined as average values over long time frames, such as months or years. Simulations have been performed using a simplified Benchmark Simulation Model No. 1 to investigate the effect of different levels of suppressing the variations of the effluent ammonium concentration. Optimisation is performed where the manipulated variable for aeration (the oxygen transfer coefficient, K(L)a) is minimised with the constraint that the average daily flow-proportional ammonium concentration in the effluent should reach a desired level. The optimisation results are compared with constant dissolved oxygen concentrations and supervisory ammonium control with different controller settings. The results demonstrate and explain how and why energy consumption can be optimised by tolerating the ammonium concentration to vary around a given average value. In these simulations, the optimal oxygen peak-to-peak amplitude range between 0.7 and 1.8 mg/l depending on the influent variation and ammonium level in the effluent. These variations can be achieved with a slow ammonium feedback controller. The air flow requirements can be reduced by 1-4% compared to constant dissolved oxygen set-points. Optimal control of aeration requires up to 14% less energy than needed for fast feedback control of effluent ammonium.


Assuntos
Ar , Modelos Biológicos , Nitrogênio/metabolismo , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Simulação por Computador , Oxigênio/análise , Compostos de Amônio Quaternário/análise
20.
Br J Dermatol ; 166(4): 761-70, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22182485

RESUMO

BACKGROUND: p-tert-Butylphenol-formaldehyde resin (PTBP-FR) is a common component of glues used in the manufacturing of many plastic, electronic, rubber, wood and leather products. Two main allergens of PTBP-FR have been described. OBJECTIVES: To determine the concentrations of the two main allergens of PTBP-FR in diagnostic patch testing preparations and PTBP-FR available to glue and adhesive manufacturers. METHODS: Nuclear magnetic resonance spectrometry was used to confirm the identity and determine the purity of reference materials. High-pressure liquid chromatography was used to analyse patch test preparations and commercially available PTBP-FR. RESULTS: In the PTBP-FR in analysed patch test preparations the highest concentration of the allergenic dimer 4-tert-butyl-2-(5-tert-butyl-2-hydroxy-3-hydroxymethyl-benzyloxymethyl)-6-hydroxymethylphenol found was 1·79% and the lowest 0·21%. The highest concentration of the allergenic dimer 4-tert-butyl-2-(5-tert-butyl-2-hydroxy-benzyloxymethyl)-6-hydroxymethylphenol found in PTBP-FR of analysed patch test preparations was 0·50% and the lowest concentration found was 0·04%. In commercially available PTBP-FR the highest concentration of 4-tert-butyl-2-(5-tert-butyl-2-hydroxy-3-hydroxymethyl-benzyloxymethyl)-6-hydroxymethylphenol found was 3·7% and the highest concentration of 4-tert-butyl-2-(5-tert-butyl-2-hydroxy-benzyloxymethyl)-6-hydroxymethylphenol found was 1·1%. In three PTBP-FR samples neither allergen could be detected. CONCLUSIONS: Our data suggest that reporting resin concentration in petrolatum is not predictive of a consistent concentration of the two main allergens of PTBP-FR. The 10-fold difference in allergen concentration between different patch test preparations has significant ramifications for maintaining consistent dose of delivered allergen. The results of this study reinforce the need for patch test product standardization in the contact dermatitis community.


Assuntos
Alérgenos/análise , Testes do Emplastro/métodos , Resinas Sintéticas/química , Adesivos/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Fenóis/análise , Padrões de Referência
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