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1.
Analyst ; 149(4): 1102-1110, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38093632

RESUMO

Albuminuria is a clinical condition associated with poor kidney function, diagnosed by determining the ratio of albumin to creatinine concentrations in patient urine samples. We present a high-throughput paper spray mass spectrometry (PS-MS) method for simultaneous quantitation of urinary albumin and creatinine for potential diagnosis of albuminuria. Minimal (urine dilution) or no sample preparation is required. The analytical performance of the method was evaluated, achieving linear calibration curves (R2 > 0.99) with little inter-day variability in the slope (N = 5 days), exhibiting coefficient of variation (CV) of 8% and 3% for albumin and creatinine, respectively. LOD and LOQ for albumin were 2.1 and 7.0 mg L-1, and for creatinine were 0.01 and 0.03 mmol L-1, respectively. Intra- and inter-day (N = 5) precisions (%CV) and accuracies (%bias) were <10% and ±11%, respectively, for both analytes. The method was applied to determine albumin-to-creatinine ratios in anonymous human patient urine samples (N = 56), and a correlation of R2 = 0.9744 was achieved between the PS-MS results and validated clinical method results. This work demonstrates the utility of PS-MS to simultaneously quantify a large (albumin) and a small (creatinine) molecule directly in patient urine samples, and its potential as a tool for clinical albuminuria diagnostics.


Assuntos
Albuminúria , Rim , Humanos , Albuminúria/diagnóstico , Creatinina/urina , Urinálise , Espectrometria de Massas em Tandem/métodos
2.
Analyst ; 149(9): 2600-2608, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38529879

RESUMO

A new analytical method for chronic kidney disease (CKD) detection utilizing paper spray mass spectrometry (PS-MS) combined with machine learning is presented. The analytical protocol is rapid and simple, based on metabolic profile alterations in urine. Anonymized raw urine samples were deposited (10 µL each) onto pointed PS-MS sample strips. Without waiting for the sample to dry, 75 µL of acetonitrile and high voltage were applied to the strips, using high resolution mass spectrometry measurement (15 s per sample) with polarity switching to detect a wide range of metabolites. Random forest machine learning was used to classify the resulting data. The diagnostic performance for the potential diagnosis of CKD was evaluated for accuracy, sensitivity, and specificity, achieving results >96% for the training data and >91% for validation and test data sets. Metabolites selected by the classification model as up- or down-regulated in healthy or CKD samples were tentatively identified and in agreement with previously reported literature. The potential utilization of this approach to discriminate albuminuria categories (normo, micro, and macroalbuminuria) was also demonstrated. This study indicates that PS-MS combined with machine learning has the potential to be used as a rapid and simple diagnostic tool for CKD.


Assuntos
Aprendizado de Máquina , Espectrometria de Massas , Insuficiência Renal Crônica , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/urina , Humanos , Espectrometria de Massas/métodos , Papel , Albuminúria/diagnóstico , Albuminúria/urina , Testes de Diagnóstico Rápido
3.
Nicotine Tob Res ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38785358

RESUMO

INTRODUCTION: People with cancer who smoke exhibit greater cigarette dependence than people without cancer who smoke, a crucial factor in smoking cessation. Research is limited on the predictive potential of the Fagerström Test for Cigarette Dependence (FTCD) and the Heaviness of Smoking Index (HSI) on smoking abstinence in cancer patients undergoing smoking cessation treatment. METHODS: We analyzed data from 5,934 cancer patients seeking smoking cessation treatment at The University of Texas MD Anderson Cancer Center (female 52.08%; Mean age = 55.52, SD = 11.17). We evaluated the predictive accuracy of FTCD and HSI on abstinence at 3-, 6-, and 9-months from first consultation, and assessed the concordance between these tools in measuring cigarette dependence using Cohen's kappa test and different correlation and regression models. We also analyzed variations across sex at birth and race/ethnicity. RESULTS: Both the FTCD and the HSI demonstrated comparable predictive accuracy for smoking cessation at all follow-ups, with neither showing high accuracy (Areas Under the Curve scores around 0.6). Concordance analysis revealed substantial agreement between FTCD and HSI scores (Cohen's kappa ~ 0.7), particularly at lower levels of dependence. However, this agreement varied by race, with reduced concordance observed in Non-Hispanic Blacks. CONCLUSIONS: Our results indicate that both the FTCD and HSI are effective tools for predicting smoking cessation in cancer patients, with the HSI offering a less burdensome assessment option. Nevertheless, the findings suggest the need for tailored approaches in assessing cigarette dependence that could predict smoking cessation more accurately, considering racial differences. IMPLICATIONS: The burden of assessing cigarette dependence in cancer care settings can be reduced by using the HSI instead of the FTCD. In addition, both instruments could be substantially interchanged and used for meta-analytic studies examining dependence and abstinence, but race/ethnicity should be considered.

4.
Am J Addict ; 33(3): 339-342, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37807121

RESUMO

BACKGROUND AND OBJECTIVES: We provide an initial characterization of e-cigarette use among adult cancer patients. METHODS: Data were collected between November 2020 and August 2022 at a comprehensive cancer center. RESULTS: Relatively few (4.59%) of the assessed patients (n = 47,117) reported ever using e-cigarettes. Over one-third of current e-cigarette users reported being current combustible cigarette users. DISCUSSION AND CONCLUSIONS: These data suggest that e-cigarette use is uncommon but associated with other tobacco use among adult cancer patients. SCIENTIFIC SIGNIFICANCE: This is among the first comprehensive surveys of adult cancer patient e-cigarette use that details the types of e-cigarette and other tobacco products used by this population.

5.
JAMA ; 331(20): 1722-1731, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38696203

RESUMO

Importance: Most people who smoke do not quit on their initial attempt. Objective: To determine the best subsequent strategy for nonabstinence following initial treatment with varenicline or combined nicotine replacement therapy (CNRT). Design, Setting, and Participants: Using a double-blind, placebo-controlled, sequential multiple assignment randomized trial, 490 volunteers were randomized to receive 6 weeks of varenicline or CNRT. After 6 weeks, nonabstainers were rerandomized to continue, switch, or increase medication dosage for 6 additional weeks. The study was conducted from June 2015 through October 2019 in a Texas tobacco treatment clinic. Interventions: The initial treatment was 2 mg/d of varenicline or the combined replacement therapy of a 21-mg patch plus 2-mg lozenge. The rerandomized participants either continued with their initial therapies, switched between varenicline and CNRT, or increased dosages either to 3-mg or more of varenicline or to a 42-mg patch and lozenges. All received weekly brief counseling. Main Outcomes and Measures: Biochemically verified 7-day point prevalence abstinence at the end of treatment at 12 weeks. Results: The 490 randomized participants (210 female [43%], 287 non-Hispanic White [58%], mean age, 48.1 years) smoked an average of 20 cigarettes per day. After the first phase, 54 participants in the CNRT group were abstinent and continued their therapy; of the 191 who were not abstinent, 151 were rerandomized, and the 40 who did not return for rerandomization were assigned to continue their initial CNRT condition in phase 2. The end-of-treatment abstinence rate for the 191 phase 1 nonabstainers was 8% (95% credible interval [CrI], 6% to 10%) for the 90 (47%) who continued at the dosage condition, 14% (CrI, 10% to 18%) for the 50 (33%) who increased their dosage, and 14% (95% CrI, 10% to 18%) for the 51 (34%) who switched to varenicline (absolute risk difference [RD], 6%; 95% CrI, 6% to 11%) with more than 99% posterior probability that either strategy conferred benefit over continuing the initial dosage. After the first phase, 88 participants in the varenicline group were abstinent and continued their therapy; of the 157 who were not abstinent, 122 were rerandomized and 35 who did not return for rerandomization were assigned to continue with the varenicline condition. The end-of-treatment abstinence rate for the 157 phase 1 nonabstainers was 20% (95% CrI, 16% to 26%) for the 39 (32%) who increased their varenicline dosage, 0 (95% CrI, 0 to 0) for the 41 (34%) who switched CNRT, and 3% (95% CrI, 1% to 4%) for the 77 (49%) who were assigned to the continued varenicline condition (absolute RD, -3%; 95% CrI, -4% to -1%) with more than 99% posterior probability that continuing varenicline at the initial dosage was worse than switching to a higher dosage. Furthermore, increasing the varenicline dosage had an absolute RD of 18% (95% CrI, 13% to 24%) and a more than 99% posterior probability of conferring benefit. The secondary outcome of continuous abstinence at 6 months indicated that only increased dosages of the CNRT and varenicline provided benefit over continuation of the initial treatment dosages. Conclusions and Relevance: For individuals who smoked but did not achieve abstinence after treatment with varenicline, increasing the dosage enhanced abstinence vs continuing, whereas for nonabstainers initially treated with CNRT, a dosage increase or switch to varenicline enhanced abstinence and may be viable rescue strategies. Trial Registration: ClinicalTrials.gov Identifier: NCT02271919.


Assuntos
Nicotina , Agonistas Nicotínicos , Agentes de Cessação do Hábito de Fumar , Abandono do Hábito de Fumar , Vareniclina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Duplo-Cego , Nicotina/administração & dosagem , Nicotina/efeitos adversos , Nicotina/uso terapêutico , Agonistas Nicotínicos/administração & dosagem , Agonistas Nicotínicos/uso terapêutico , Abandono do Hábito de Fumar/métodos , Agentes de Cessação do Hábito de Fumar/uso terapêutico , Agentes de Cessação do Hábito de Fumar/efeitos adversos , Agentes de Cessação do Hábito de Fumar/administração & dosagem , Falha de Tratamento , Vareniclina/uso terapêutico , Vareniclina/administração & dosagem , Vareniclina/efeitos adversos , Brancos
6.
Phys Rev Lett ; 128(19): 197701, 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35622052

RESUMO

Josephson parametric amplifiers (JPAs) approaching quantum-limited noise performance have been instrumental in enabling high fidelity readout of superconducting qubits and, recently, semiconductor quantum dots (QDs). We propose that the quantum capacitance arising in electronic two-level systems (the dual of Josephson inductance) can provide an alternative dissipationless nonlinear element for parametric amplification. We experimentally demonstrate phase-sensitive parametric amplification using a QD-reservoir electron transition in a CMOS nanowire split-gate transistor embedded in a 1.8 GHz superconducting lumped-element microwave cavity, achieving parametric gains of -3 to +3 dB, limited by Sisyphus dissipation. Using a semiclassical model, we find an optimized design within current technological capabilities could achieve gains and bandwidths comparable to JPAs, while providing complementary specifications with respect to integration in semiconductor platforms or operation at higher magnetic fields.

7.
Alcohol Clin Exp Res ; 46(3): 384-395, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35037278

RESUMO

BACKGROUND: There is preliminary evidence that the anticonvulsant topiramate increases the likelihood of both smoking and alcohol abstinence among smokers with alcohol use disorder (AUD), but its therapeutic mechanism has not been determined. We used event-related potentials (ERPs) to evaluate topiramate's effect on the salience of drug-related, emotional, and neutral pictorial cues to identify whether one of its potential therapeutic mechanisms involves reduction of the salience of motivationally relevant cues. METHODS: Participants enrolled in a multisite clinical trial treating smokers with AUD were randomly assigned to receive placebo, low-dose topiramate (up to 125 mg/day), or high-dose topiramate (up to 250 mg/day), along with brief behavioral compliance enhancement treatment. A subsample (n = 101) completed ERP assessments at baseline (1 week pre-medication) and week 5 (5 weeks on medication; 1 week pre-quit). We assessed the salience of pleasant, unpleasant, cigarette-related, alcohol-related, and neutral pictorial cues using the late positive potential (LPP) ERP component and measured self-reported substance use, reinforcement, craving, and withdrawal. RESULTS: Five weeks of high-dose topiramate treatment decreased LPP amplitudes in response to both emotional (pleasant and unpleasant) and drug-related cues (alcohol and cigarette), but not to neutral cues. However, results showed that the LPPs were not significant mediators of the relationship between topiramate dose and post-quit measures of substance use, reinforcement, craving, or withdrawal. CONCLUSIONS: These findings suggest that high-dose topiramate (up to 250 mg/day) decreases the motivational salience of both drug-related and emotional cues among smokers with AUD. However, the nonsignificant mediation analyses preclude any firm conclusions about whether this effect represents one of topiramate's therapeutic mechanisms of action.


Assuntos
Alcoolismo , Fumantes , Consumo de Bebidas Alcoólicas , Alcoolismo/tratamento farmacológico , Alcoolismo/psicologia , Sinais (Psicologia) , Humanos , Fumantes/psicologia , Topiramato/uso terapêutico
8.
Prev Med ; 165(Pt B): 107175, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35870575

RESUMO

The United States Food and Drug Administration has the authority to reduce the nicotine content in cigarettes to minimal or non-addictive levels and could do so immediately or gradually over time. A large clinical trial compared the two approaches. This secondary analysis assesses abstinence and cessation-related outcomes one month after the trial concluded, when participants no longer had access to very low nicotine content (VLNC) research cigarettes. Smokers not interested in quitting (N = 1250) were recruited for the parent trial from 2014 to 2016 across 10 sites throughout the US and randomized to a 20-week study period during which they immediately switched to VLNC cigarettes, gradually transitioned to VLNC cigarettes with five monthly dose reductions, or smoked normal nicotine research cigarettes (control). At the one-month follow-up, both immediate and gradual reduction resulted in greater mean cigarette-free days (4.7 and 4.6 respectively) than the control group (3.2, both p < .05). Immediate reduction resulted in fewer mean cigarettes per day (CPD = 10.3) and lower Fagerström Test for Cigarette Dependence (FTCD = 3.7) than the gradual (CPD = 11.7, p = .001; FTCD = 3.8, p = .039) and control (CPD = 13.5, p < .001; FTCD = 4.0, p < .001) groups. Compared to controls, gradual reduction resulted in reduced CPD (p = .012) but not FTCD (p = .13). Differences in CO-verified 7-day point-prevalence abstinence were not significant. Findings demonstrate that switching to VLNC cigarettes resulted in reduced smoking and nicotine dependence severity that was sustained for at least a month after the VLNC trial period in smokers who were not interested in cessation. The greatest harm reduction endpoints were observed in those who immediately transitioned to VLNC cigarettes.


Assuntos
Abandono do Hábito de Fumar , Produtos do Tabaco , Tabagismo , Estados Unidos , Humanos , Nicotina/efeitos adversos , Nicotina/análise , Abandono do Hábito de Fumar/métodos , Fumar
9.
Nicotine Tob Res ; 24(11): 1773-1780, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-35511741

RESUMO

INTRODUCTION: There is mixed evidence regarding whether older (vs. younger) smokers are more or less likely to quit smoking. We examined how age is associated with cigarette and all tobacco product abstinence and the potential moderating effects of smoking frequency. AIMS AND METHODS: Data from a 4-year cohort of the Population Assessment of Tobacco and Health (PATH) study were used, including 7512 smokers at Wave 1 who had smoking status data at Wave 4. Logistic regression models were used to examine the effects of age (18-24, 25-34, 35-44, 45-54, and ≥55 years) on Wave 4, 30-day and 12-month cigarette and all tobacco product abstinence, adjusting for covariates and the interaction between age and cigarette use frequency (nondaily, light daily, and heavy daily). RESULTS: Older smokers (≥55 years) were more likely to be heavy daily smokers than younger smokers 18-24 and 25-34 years, but were less likely to have a past-year cigarette quit attempt. Younger smokers 45-54 years were less likely to report 12-month cigarette abstinence than older smokers (odds ratio = 0.72 [0.54-0.95]). Younger smokers 18-24 and 45-54 years were less likely to report 12-month tobacco product abstinence than older smokers (odds ratio = 0.65 [0.45-0.93]; odds ratio = 0.73 [0.55-0.96], respectively). Thirty-day cigarette abstinence significantly decreased as age increased for nondaily smokers, significantly increased for heavier daily smokers, but remained similar across age for light daily smokers. CONCLUSIONS: Older smokers were more likely to report 12-month cigarette and tobacco abstinence than younger smokers 45-54 years old, and the effect of age on abstinence differed by smoking frequency/intensity. Smoking cessation interventions need to be age specific and consider smoking frequency. IMPLICATIONS: This study shows that although older smokers are more likely to be heavy smokers and less likely to have a quit attempt at baseline, they are more likely to have 12-month cigarette and tobacco abstinence than younger smokers. Furthermore, 30-day cigarette abstinence significantly decreases as age increases for nondaily smokers and significantly increases for heavy daily smokers, suggesting that the effect of cigarette smoking frequency and intensity changes with age. Smoking cessation interventions need to be age specific as well as consider the smoking frequency/intensity of each age group. Younger smokers may need more targeted cessation interventions to successfully quit.


Assuntos
Abandono do Hábito de Fumar , Produtos do Tabaco , Humanos , Pessoa de Meia-Idade , Fumantes , Nicotiana , Fumar
10.
Nicotine Tob Res ; 24(1): 146-148, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33912971

RESUMO

INTRODUCTION: In smoking cessation clinical trials, timeline followback (TLFB) interviews are widely used to track daily cigarette consumption. However, there are no standard tools for calculating abstinence based on TLFB data. Individual research groups have to develop their own calculation tools, which is not only time- and resource-consuming but might also lead to variability in the data processing and calculation procedures. AIMS AND METHODS: To address these issues, we developed a novel open-source Python package named abstcal to calculate abstinence using TLFB data. This package provides data verification, duplicate and outlier detection, missing-data imputation, integration of biochemical verification data, and calculation of a variety of definitions of abstinence, including continuous, point-prevalence, and prolonged abstinence. RESULTS: We verified the accuracy of the calculator using data derived from a clinical smoking cessation study. To improve the package's accessibility, we have made it available as a free web app. CONCLUSIONS: The abstcal package is a reliable abstinence calculator with open-source access, providing a shared validated online tool to the addiction research field. We expect that this open-source abstinence calculation tool will improve the rigor and reproducibility of smoking and addiction research by standardizing TLFB-based abstinence calculation. IMPLICATIONS: Abstinence calculation is an essential task in any smoking intervention study. However, there have not been standard open-source tools available to the researchers. This commentary describes a Python-based package called abstcal that can calculate abstinence from TLFB data, a common methodology to collect smoking consumption data in research settings. The package supports the calculation of point-prevalence, prolonged, and continuous abstinence. Importantly, the package has a web app interface that allows researchers to use the tool without any coding experience. This tool will facilitate smoking research by providing a standardized and easy-to-use abstinence calculation tool.


Assuntos
Abandono do Hábito de Fumar , Humanos , Reprodutibilidade dos Testes , Fumar
11.
Am J Addict ; 31(3): 236-241, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35347796

RESUMO

BACKGROUND AND OBJECTIVES: Bupropion extended-release (XL; once-daily dosing) has equal efficacy with the sustained-release (SR) formulation (twice-daily dosing) for treating depression, but no studies have compared the two formulations for the treatment of smoking. In a naturalistic open-label study, we compared the effectiveness and the adverse event profiles of XL and SR in treating cancer patients for smoking. METHODS: Cancer patients (N = 648) were prescribed bupropion XL (n = 454) or SR (n = 194) alone or in combination with nicotine replacement therapy (NRT) for treating smoking from September 2006 to December 2017. We analyzed 7-day point prevalence abstinence at end-of-treatment (EOT; 3 months postmedication initiation) and evaluated for noninferiority. We also analyzed the adverse event profile differences between the medications. RESULTS: There were no significant differences in abstinent rates at EOT between bupropion XL and SR when using intent-to-treat models, regardless of concomitant NRT. XL demonstrated noninferiority in treatment efficacy compared to SR when excluding those on combined treatment with NRT. Further, there were no significant differences in spontaneously reported adverse events between XL and SR. CONCLUSIONS: Our data did not reveal a difference between bupropion XL and SR formulations in terms of effectiveness or adverse event profiles among cancer patients prescribed bupropion alone or in combination with NRTs to quit smoking. SCIENTIFIC SIGNIFICANCE: In this first published direct comparison of their effectiveness and adverse event profiles, we found that bupropion XL is likely therapeutically equivalent to bupropion SR when treating smoking among cancer patients, and produces similar side effects.


Assuntos
Neoplasias , Abandono do Hábito de Fumar , Bupropiona/efeitos adversos , Humanos , Neoplasias/tratamento farmacológico , Fumar/efeitos adversos , Fumar/tratamento farmacológico , Fumar Tabaco , Dispositivos para o Abandono do Uso de Tabaco/efeitos adversos
12.
Nano Lett ; 21(15): 6511-6517, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34320314

RESUMO

Spin accumulation is generated by passing a charge current through a ferromagnetic layer and sensed by other ferromagnetic layers downstream. Pure spin currents can also be generated in which spin currents flow and are detected as a nonlocal resistance in which the charge current is diverted away from the voltage measurement point. Here, we report nonlocal spin-transport on two-dimensional surface-conducting SrTiO3 (STO) without a ferromagnetic spin-injector via the spin Hall effect (and inverse spin Hall effect). By applying magnetic fields to the Hall bars at different angles to the nonlocal spin-diffusion, we demonstrate an anisotropic spin-signal that is consistent with a Hanle precession of a pure spin current. We extract key transport parameters for surface-conducting STO, including: a spin Hall angle of γ ≈ (0.25 ± 0.05), a spin lifetime of τ ∼ 49 ps, and a spin diffusion length of λs ≈ (1.23 ± 0.7) µm at 2 K.

13.
Nano Lett ; 21(7): 3092-3097, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33724857

RESUMO

Spin-singlet Cooper pairs convert to spin-triplet Cooper pairs on passing through a magnetically noncollinear structure at a superconductor(S)/ferromagnet(F) interface. In this context, the generation of triplet supercurrents through intrinsic ferromagnetic domain walls, which are naturally occurring noncollinear magnetic features, was proposed theoretically in the past decade. However, an experimental demonstration has been lacking in the literature, particularly because of the difficulty in accessing a single domain wall, which is typically buried between two domains in a ferromagnetic material. By patterning a ferromagnetic nanoconstriction, we have been able to realize a nanoscale S/F/S planar junction, where a single domain wall (pinned at the nanoconstriction) acts as a Josephson barrier. In this geometry, we are able to show the predicted long-range triplet supercurrent across a ferromagnetic barrier exceeding 70 nm. Using this technique, we have demonstrated a ferromagnetic planar nano-SQUID device consisting of two Nb/Ni/Nb spin-triplet Josephson junctions.

14.
Nano Lett ; 21(10): 4185-4192, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33979525

RESUMO

Ruddlesden-Popper (RP) phases (An+1BnO3n+1, n = 1, 2,···) have attracted intensive research with diverse functionalities for device applications. However, the realization of a high-quality RP-phase film is hindered by the formation of out-of-phase boundaries (OPBs) that occur at terrace edges, originating from lattice mismatch in the c-axis direction with the A'B'O3 (n = ∞) substrate. Here, using strontium ruthenate RP-phase Sr2RuO4 (n = 1) as a model system, an experimental approach for suppressing OPBs was developed. By tuning the growth parameters, the Sr3Ru2O7 (n = 2) phase was formed in a controlled manner near the film-substrate interface. This higher-order RP-phase then blocked the subsequent formation of OPBs, resulting in nearly defect-free Sr2RuO4 layer at the upper region of the film. Consequently, the Sr2RuO4 thin films exhibited superconductivity up to 1.15 K, which is the highest among Sr2RuO4 films grown by pulsed laser deposition. This work paves the way for synthesizing pristine RP-phase heterostructures and exploring their unique physical properties.

15.
Phys Rev Lett ; 127(26): 267001, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35029472

RESUMO

Unconventional superconductors are of high interest due to their rich physics, a topical example being topological edge states associated with p-wave superconductivity. A practical obstacle in studying such systems is the very low critical temperature T_{c} that is required to realize a p-wave superconducting phase in a material. We predict that the T_{c} of an intrinsic p-wave superconductor can be significantly enhanced by coupling to a conventional s-wave or d-wave superconductor with a higher critical temperature via an atomically thin ferromagnetic (F) layer. We show that this T_{c} boost is tunable via the direction of the magnetization in F. Moreover, we show that the enhancement in T_{c} can also be achieved using the Zeeman effect of an external magnetic field. Our findings provide a way to increase T_{c} in p-wave superconductors in a controllable way and make the exotic physics associated with such materials more easily accessible experimentally.

16.
J Lipid Res ; 61(7): 1038-1051, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32350078

RESUMO

Multi-component lipid emulsions, rather than soy-oil emulsions, prevent cholestasis by an unknown mechanism. Here, we quantified liver function, bile acid pools, and gut microbial and metabolite profiles in premature parenterally fed pigs given a soy-oil lipid emulsion, Intralipid (IL), a multi component lipid emulsion, SMOFlipid (SMOF), a novel emulsion with a modified fatty-acid composition [experimental emulsion (EXP)], or a control enteral diet (ENT) for 22 days. We assayed serum cholestasis markers, measured total bile acid levels in plasma, liver, and gut contents, and analyzed colonic bacterial 16S rRNA gene sequences and metabolomic profiles. Serum cholestasis markers (i.e., bilirubin, bile acids, and γ-glutamyl transferase) were highest in IL-fed pigs and normalized in those given SMOF, EXP, or ENT. Gut bile acid pools were lowest in the IL treatment and were increased in the SMOF and EXP treatments and comparable to ENT. Multiple bile acids, especially their conjugated forms, were higher in the colon contents of SMOF and EXP than in IL pigs. The colonic microbial communities of SMOF and EXP pigs had lower relative abundance of several gram-positive anaerobes, including Clostridrium XIVa, and higher abundance of Enterobacteriaceae than those of IL and ENT pigs. Differences in lipid and microbial-derived compounds were also observed in colon metabolite profiles. These results indicate that multi-component lipid emulsions prevent cholestasis and restore enterohepatic bile flow in association with gut microbial and metabolomic changes. We conclude that sustained bile flow induced by multi-component lipid emulsions likely exerts a dominant effect in reducing bile acid-sensitive gram-positive bacteria.


Assuntos
Ácidos e Sais Biliares/metabolismo , Colestase/metabolismo , Colestase/microbiologia , Metabolismo dos Lipídeos , Microbiota , Nascimento Prematuro/metabolismo , Nascimento Prematuro/microbiologia , Animais , Colestase/complicações , Nutrição Parenteral , Suínos
17.
Brain Behav Immun ; 85: 46-56, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31026499

RESUMO

New generation, multicomponent parenteral lipid emulsions provide key fatty acids for brain growth and development, such as docosahexaenoic acid (DHA) and arachidonic acid (AA), yet the content may be suboptimal for preterm infants. Our aim was to test whether DHA and AA-enriched lipid emulsions would increase activity, growth, and neurodevelopment in preterm piglets and limit brain inflammation. Cesarean-delivered preterm pigs were given three weeks of either enteral preterm infant formula (ENT) or TPN with one of three parenteral lipid emulsions: Intralipid (IL), SMOFlipid (SMOF) or an experimental emulsion (EXP). Activity was continuously monitored and weekly blood sampling and behavioral field testing performed. At termination of the study, whole body and tissue metrics were collected. Neuronal density was assessed in sections of hippocampus (HC), thalamus, and cortex. Frontal cortex (FC) and HC tissue were assayed for fatty acid profiles and expression of genes of neuronal growth and inflammation. After 3 weeks of treatment, brain DHA content in SMOF, EXP and ENT pigs was higher (P < 0.01) in FC but not HC vs. IL pigs. There were no differences in brain weight or neuron density among treatment groups. Inflammatory cytokine TNFα and IL-1ß expression in brain regions were increased in IL pigs (P < 0.05) compared to other groups. Overall growth velocity was similar among groups, but IL pigs had higher percent body fat and increased insulin resistance compared to other treatments (P < 0.05). ENT pigs spent more time in higher physical activity levels compared to all TPN groups, but there were no differences in exploratory behavior among groups. We conclude that a soybean oil emulsion increased select brain inflammatory cytokines and multicomponent lipid emulsions enriched with DHA and AA in parenteral lipids results in increased cortical DHA and improved body composition without affecting short term neurodevelopmental outcomes.


Assuntos
Ácidos Docosa-Hexaenoicos , Recém-Nascido Prematuro , Animais , Composição Corporal , Encéfalo , Emulsões , Feminino , Óleos de Peixe , Humanos , Recém-Nascido , Azeite de Oliva , Gravidez , Óleo de Soja , Suínos , Triglicerídeos
18.
Nicotine Tob Res ; 22(8): 1277-1284, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31724052

RESUMO

INTRODUCTION: By improving our understanding of the neurobiological mechanisms underlying addiction, neuroimaging research is helping to identify new targets for personalized treatment interventions. When trying to quit, smokers with larger electrophysiological responses to cigarette-related, compared with pleasant, stimuli ("C > P") are more likely to relapse than smokers with the opposite brain reactivity profile ("P > C"). AIM AND METHOD: The goal was to (1) build a classification algorithm to identify smokers characterized by P > C or C > P neuroaffective profiles and (2) validate the algorithm's classification outcomes in an independent data set where we assessed both smokers' electrophysiological responses at baseline and smoking abstinence during a quit attempt. We built the classification algorithm applying discriminant function analysis on the event-related potentials evoked by emotional images in 180 smokers. RESULTS: The predictive validity of the classifier showed promise in an independent data set that included new data from 177 smokers interested in quitting; the algorithm classified 111 smokers as P > C and 66 as C > P. The overall abstinence rate was low; 15 individuals (8.5% of the sample) achieved CO-verified 12-month abstinence. Although individuals classified as P > C were nearly 2.5 times more likely to be abstinent than smokers classified as C > P (12 vs. 3, or 11% vs. 4.5%), this result was nonsignificant, preliminary, and in need of confirmation in larger trials. CONCLUSION: These results suggest that psychophysiological techniques have the potential to advance our knowledge of the neurobiological underpinnings of nicotine addiction and improve clinical applications. However, larger sample sizes are necessary to reliably assess the predictive ability of our algorithm. IMPLICATIONS: We assessed the clinical relevance of a neuroimaging-based classification algorithm on an independent sample of smokers enrolled in a smoking cessation trial and found those with the tendency to attribute more relevance to rewards than cues were nearly 2.5 times more likely to be abstinent than smokers with the opposite brain reactivity profile (11% vs. 4.5%). Although this result was not statistically significant, it suggests our neuroimaging-based classification algorithm can potentially contribute to the development of new precision medicine interventions aimed at treating substance use disorders. Regardless, these findings are still preliminary and in need of confirmation in larger trials.


Assuntos
Algoritmos , Neuroimagem/métodos , Medicina de Precisão , Fumantes/psicologia , Abandono do Hábito de Fumar/estatística & dados numéricos , Tabagismo/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Abandono do Hábito de Fumar/métodos , Tabagismo/epidemiologia , Tabagismo/psicologia , Estados Unidos/epidemiologia
19.
Nicotine Tob Res ; 22(8): 1294-1300, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31701153

RESUMO

INTRODUCTION: Smoking to reduce negative affect has been identified as a key motivational feature of tobacco use. Our recent work suggests that smoking very low nicotine content (VLNC) cigarettes reduces the relationship between negative affect and smoking behavior over a 6-week period. Here, we sought to extend our findings by evaluating whether a gradual or immediate approach to switching to VLNC cigarettes led to a differential reduction in the relationship between affect and smoking behavior over a longer (20-week) period. AIMS AND METHODS: Participants (n = 1250) were adult smokers from 10 US sites randomized to one of three groups: gradual nicotine reduction (15.5, 11.7, 5.2, 2.4, and 0.4 mg of nicotine per gram of tobacco [mg/g]), immediate nicotine reduction (0.4 mg/g), or standard nicotine content cigarettes (15.5 mg/g; control), for 20 weeks. We examined whether the relationship between affect-both negative and positive-and cigarettes per day differed as a function of reduction group. RESULTS: We found that both negative and positive affect were associated with cigarette consumption in the control group, but not in the gradual or immediate reduction groups across the 20 weeks of exposure. CONCLUSIONS: Our results extend previous findings that switching to VLNC cigarettes disrupts the relationship between affect and cigarette consumption by showing that either gradually or immediately reducing cigarette nicotine content achieves this disruption. These findings provide further evidence that switching to VLNC cigarettes reduces nicotine-related reinforcement of cigarette smoking. IMPLICATIONS: These findings support the notion that switching to very low nicotine content cigarettes reduces the association between affect and smoking behavior, and that either a gradual or immediate nicotine reduction approach achieves this reduction. This provides further evidence that switching to very low nicotine content cigarettes weakens reinforcement mechanisms associated with nicotine dependence.


Assuntos
Fumar Cigarros/psicologia , Retroalimentação , Nicotina/análise , Reforço Psicológico , Fumantes/psicologia , Fumar/psicologia , Tabagismo/psicologia , Adolescente , Adulto , Estudos de Casos e Controles , Fumar Cigarros/epidemiologia , Método Duplo-Cego , Emoções , Feminino , Humanos , Masculino , Motivação , Nicotina/administração & dosagem , Abandono do Hábito de Fumar/métodos , Produtos do Tabaco/estatística & dados numéricos , Estados Unidos/epidemiologia , Adulto Jovem
20.
Am J Physiol Gastrointest Liver Physiol ; 316(5): G641-G652, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30920308

RESUMO

Enteroendocrine L cells and glucagon-like peptide 2 (GLP-2) secretion are activated in the intestinal adaptation process following bowel resection in patients with short bowel syndrome. We hypothesized that enteral activation of Takeda G protein-coupled receptor 5 (TGR5), expressed in enteroendocrine L cells, could augment endogenous GLP-2 secretion and the intestinal adaptation response. Our aim was to assess the efficacy of different TGR5 agonists to stimulate GLP-2 secretion and intestinal adaptation in a piglet short-bowel model. In study 1, parenterally fed neonatal pigs (n = 6/group) were gavaged with vehicle, olive extract (OE; 10 or 50 mg/kg), or ursolic acid (UA; 10 mg/kg), and plasma GLP-2 was measured for 6 h. In study 2, neonatal pigs (n = 6-8/group) were subjected to transection or 80% mid-small intestine resection and, after 2 days, assigned to treatments for 10 days as follows: 1) transection + vehicle (sham), 2) resection + vehicle (SBS), 3) resection + 30 mg UA (SBS + UA), and 4) resection + 180 mg/kg OE (SBS + OE). We measured plasma GLP-2, intestinal histology, cell proliferation, and gene expression, as well as whole body citrulline-arginine kinetics and bile acid profiles. In study 1, GLP-2 secretion was increased by UA and tended to be increased by OE. In study 2, SBS alone, but not additional treatment with either TGR5 agonist, resulted in increased mucosal thickness and crypt cell proliferation in remnant jejunum and ileum sections. SBS increased biliary and ileal concentration of bile acids and expression of inflammatory and farnesoid X receptor target genes, but these measures were suppressed by UA treatment. In conclusion, UA is an effective oral GLP-2 secretagogue in parenterally fed pigs but is not capable of augmenting GLP-2 secretion or the intestinal adaptation response after massive small bowel resection. NEW & NOTEWORTHY Therapeutic activation of endogenous glucagon-like peptide 2 (GLP-2) secretion is a promising strategy to improve intestinal adaptation in patients with short bowel syndrome. This study in neonatal pigs showed that oral supplementation with a selective Takeda G protein-coupled receptor 5 (TGR5) agonist is an effective approach to increase GLP-2 secretion. The results warrant further study to establish a more potent oral TGR5 agonist that can effectively improve intestinal adaptation in pediatric patients with SBS.


Assuntos
Peptídeo 2 Semelhante ao Glucagon/metabolismo , Mucosa Intestinal/metabolismo , Receptores Acoplados a Proteínas G , Síndrome do Intestino Curto , Adaptação Fisiológica , Animais , Animais Recém-Nascidos , Proliferação de Células , Modelos Animais de Doenças , Células Enteroendócrinas/fisiologia , Intestino Delgado/metabolismo , Nutrição Parenteral/métodos , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Síndrome do Intestino Curto/metabolismo , Síndrome do Intestino Curto/terapia , Suínos , Resultado do Tratamento
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