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1.
Eur Heart J ; 45(21): 1877-1886, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38190428

RESUMO

BACKGROUND AND AIMS: Severe aortic stenosis (AS) is the guideline-based indication for aortic valve replacement (AVR), which has markedly increased with transcatheter approaches, suggesting possible increasing AS incidence. However, reported secular trends of AS incidence remain contradictory and lack quantitative Doppler echocardiographic ascertainment. METHODS: All adults residents in Olmsted County (MN, USA) diagnosed over 20 years (1997-2016) with incident severe AS (first diagnosis) based on quantitatively defined measures (aortic valve area ≤ 1 cm2, aortic valve area index ≤ 0.6 cm2/m2, mean gradient ≥ 40 mmHg, peak velocity ≥ 4 m/s, Doppler velocity index ≤ 0.25) were counted to define trends in incidence, presentation, treatment, and outcome. RESULTS: Incident severe AS was diagnosed in 1069 community residents. The incidence rate was 52.5 [49.4-55.8] per 100 000 patient-year, slightly higher in males vs. females and was almost unchanged after age and sex adjustment for the US population 53.8 [50.6-57.0] per 100 000 residents/year. Over 20 years, severe AS incidence remained stable (P = .2) but absolute burden of incident cases markedly increased (P = .0004) due to population growth. Incidence trend differed by sex, stable in men (incidence rate ratio 0.99, P = .7) but declining in women (incidence rate ratio 0.93, P = .02). Over the study, AS clinical characteristics remained remarkably stable and AVR performance grew and was more prompt (from 1.3 [0.1-3.3] years in 1997-2000 to 0.5 [0.2-2.1] years in 2013-16, P = .001) but undertreatment remained prominent (>40%). Early AVR was associated with survival benefit (adjusted hazard ratio 0.55 [0.42-0.71], P < .0001). Despite these improvements, overall mortality (3-month 8% and 3-year 36%), was swift, considerable and unabated (all P ≥ .4) throughout the study. CONCLUSIONS: Over 20 years, the population incidence of severe AS remained stable with increased absolute case burden related to population growth. Despite stable severe AS presentation, AVR performance grew notably, but while declining, undertreatment remained substantial and disease lethality did not yet decline. These population-based findings have important implications for improving AS management pathways.


Assuntos
Estenose da Valva Aórtica , Humanos , Estenose da Valva Aórtica/epidemiologia , Masculino , Feminino , Incidência , Idoso , Pessoa de Meia-Idade , Minnesota/epidemiologia , Idoso de 80 Anos ou mais , Substituição da Valva Aórtica Transcateter/tendências , Substituição da Valva Aórtica Transcateter/estatística & dados numéricos , Ecocardiografia Doppler , Implante de Prótese de Valva Cardíaca/tendências , Implante de Prótese de Valva Cardíaca/estatística & dados numéricos , Índice de Gravidade de Doença , Resultado do Tratamento
2.
Neuromodulation ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39078348

RESUMO

OBJECTIVE: This study evaluated the effects of cessation of both conventional low-frequency (50 Hz) and high-frequency (10 kHz) spinal cord stimulation (SCS) on the cardiospinal neural network activity in pigs with myocardial infarction (MI). The objective is to provide an insight into the memory effect of SCS. MATERIALS AND METHODS: In nine Yorkshire pigs, chronic MI was created by delivering microspheres to the left circumflex coronary artery. Five weeks after MI, anesthetized pigs underwent sternotomy to expose the heart for performing acute ischemia intervention, and laminectomy to expose the T1-T4 spinal regions for extracellular in vivo neural recording and SCS. Cardiac ischemic-sensitive neurons were identified by selective responsiveness to left anterior descending (LAD) coronary artery occlusion. SCS episodes were delivered in a random order between low- (50 Hz) and high- (10 kHz) frequency, for 1 minute, at 90% of the motor threshold current. Neural firing and synchrony of ischemic-sensitive spinal neurons were evaluated before vs after SCS. RESULTS: Using a 64-channel microelectrode array, 2711 spinal neurons were recorded extracellularly. LAD ischemia excited 228 neurons that were labeled as ischemic-responsive neurons. The cessation of 50-Hz SCS caused a higher activation than did inhibition of ischemic-responsive neurons (41 activated vs 19 inhibited), whereas the cessation of 10-kHz SCS caused an opposite response with higher inhibition (11 activated vs 28 inhibited, p < 0.01 vs 50 Hz). Termination of low-frequency SCS caused an increase in ischemic-responsive neuronal firing rate compared with high-frequency SCS (50 Hz: 0.39 Hz ± 0.16 Hz, 10 kHz: -0.11 Hz ± 0.057 Hz, p < 0.01). In addition, SCS delivered at 50 Hz increased the number of synchronized pairs of neurons by 205 pairs, whereas high-frequency SCS decreased the number of synchronized pairs by 345 pairs (p < 0.01). CONCLUSIONS: High-frequency (10 kHz) stimulation provides persistent suppression of the ischemia-sensitive neurons after termination of SCS. In contrast, the spinal neural network reverted to excitatory state after termination of low-frequency (50 Hz) stimulation.

3.
Gastroenterology ; 163(1): 154-162.e3, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35364066

RESUMO

BACKGROUND & AIMS: Helicobacter pylori infection is considered as the most important risk factor in the pathogenesis of gastric cancer. This study aims to evaluate the long-term effects of H pylori eradication treatment on the incidence and mortality of gastric cancer among a high-risk population. METHODS: This prospective, randomized, placebo-controlled trial was conducted in a high-risk area in southern China in July 1994. A total of 1630 asymptomatic, H pylori-infected individuals were randomly assigned to receive standard triple therapy for H pylori eradication (n = 817) or placebo (n = 813), and were followed up until December 2020. The primary outcome was incidence of gastric cancer. Total and cause-specific mortalities were the secondary outcomes. RESULTS: During 26.5 years of follow-up, 21 participants (2.57%) in the treatment arm and 35 (4.31%) in the placebo arm were diagnosed with gastric cancer. Participants receiving H pylori treatment had a lower incidence of gastric cancer compared with their placebo counterparts (hazard ratio [HR], 0.57; 95% CI, 0.33-0.98). More obvious risk reduction was observed among those without premalignant gastric lesions (HR, 0.37; 95% CI, 0.15-0.95) and those without dyspepsia symptoms at baseline (HR, 0.44; 95% CI, 0.21-0.94). Furthermore, compared with 32 cases of gastric cancer observed among 527 participants with persistent H pylori infection in the placebo group, only 16 were identified in 625 subjects with successful eradication in the treatment group (HR, 0.46; 95% CI, 0.26-0.83). However, there were no statistically significant differences for any mortality end points between the 2 groups. CONCLUSIONS: Eradication of H pylori might confer a long-term protection against gastric cancer in high-risk populations, especially for infected individuals without precancerous gastric lesions at baseline.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Neoplasias Gástricas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Quimioterapia Combinada , Seguimentos , Infecções por Helicobacter/complicações , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Humanos , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/tratamento farmacológico , Lesões Pré-Cancerosas/epidemiologia , Estudos Prospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/prevenção & controle
4.
Eur Econ Rev ; 153: 104385, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36714546

RESUMO

We estimate the euro area output gap by applying the Beveridge-Nelson decomposition based on a large Bayesian vector autoregression. Our approach incorporates multivariate information through the inclusion of a wide range of variables in the analysis and addresses data issues associated with the COVID-19 pandemic. The estimated output gap lines up well with the CEPR chronology of the business cycle for the euro area and we find that hours worked, more than the unemployment rate, provides the key source of information about labor utilization in the economy, especially in pinning down the depth of the output gap during the COVID-19 recession when the unemployment rate rose only moderately. Our findings confirm that labor market adjustments to the business cycle in the euro area occur more through the intensive, rather than extensive, margin.

5.
Addict Biol ; 27(6): e13237, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36301206

RESUMO

One of the most challenging issues in the treatment of substance use disorder, including misuse of opioids such as oxycodone, is persistent vulnerability to relapse, often triggered by cues or contexts previously associated with drug use. In rats, cue-induced craving progressively intensifies ('incubates') during withdrawal from extended-access self-administration of several classes of misused drugs, including the psychostimulants cocaine and methamphetamine. For these psychostimulants, incubation is associated with strengthening of excitatory synapses in the nucleus accumbens (NAc) through incorporation of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors that lack the GluA2 subunit and are therefore Ca2+ -permeable (CP-AMPARs). Once CP-AMPAR upregulation occurs, their stimulation is required for expression of incubation. It is not known if a similar mechanism contributes to incubation of oxycodone craving. Using male rats, we established that incubation occurs by withdrawal day (WD) 15 and persists through WD30. Then, using cell-surface biotinylation, we found that surface levels of the AMPAR subunit GluA1 but not GluA2 are elevated in NAc core and shell of oxycodone rats on WD15, although this wanes by WD30. Next, using intra-NAc injection of the selective CP-AMPAR antagonist Naspm before a seeking test, we demonstrate that CP-AMPAR blockade in either subregion decreases oxycodone seeking on WD15 or WD30 (after incubation), but not WD1, and has no effect in saline self-administering animals. The Naspm results suggest CP-AMPARs persist in synapses through WD30 even if total cell surface levels wane. These results suggest that a common neurobiological mechanism contributes to expression of incubation of craving for oxycodone and psychostimulants.


Assuntos
Cocaína , Síndrome de Abstinência a Substâncias , Ratos , Masculino , Animais , Núcleo Accumbens , Receptores de AMPA/metabolismo , Fissura/fisiologia , Oxicodona/farmacologia , Oxicodona/metabolismo , Síndrome de Abstinência a Substâncias/metabolismo , Ratos Sprague-Dawley , Cocaína/farmacologia , Autoadministração
6.
Toxicol Appl Pharmacol ; 427: 115652, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34298059

RESUMO

Exposure to phosphine (PH3) presents with a host of diverse, non-specific symptoms that span multiple organ systems and is characterized by a high mortality rate. While a comprehensive mechanism for PH3 poisoning remains inconclusive, prior studies have implicated cardiac failure and circulatory compromise as potential pathways central to PH3-induced mortality. In this study, milrinone (MLR), a phosphodiesterase-3 inhibitor used to treat cardiac failure, was investigated as a potential countermeasure for PH3 poisoning. Lethality, physiological responses, and behavioral changes were evaluated in telemetrized female rats pretreated with water (sham) or one of three doses of MLR (40, 200, or 600 µg/kg) and exposed to PH3 (660 ppm for 25-40 min; 16,500-26,400 ppm × min). Animals receiving prophylactic administration of 600 µg/kg of MLR had nominally improved survivability compared to sham animals, although median lethal concentration-time and time of death did not differ substantially between treatment groups. Changes in respiration and behavior induced by PH3 appeared largely unaffected by MLR pretreatment, regardless of dose. Conversely, MLR pretreatment alleviated some aspects of PH3-induced cardiac function impairment, with slight dose-dependent effects observed for cardiac contractility, mean arterial pressure, and QRS duration. Together, these results illustrate the importance of circulatory compromise in PH3 poisoning and highlight the potential viability of MLR as a potential countermeasure option or part of a countermeasure regimen when administered prophylactically at 600 µg/kg.


Assuntos
Débito Cardíaco/efeitos dos fármacos , Cardiotônicos/administração & dosagem , Inseticidas/intoxicação , Milrinona/administração & dosagem , Fosfinas/intoxicação , Mecânica Respiratória/efeitos dos fármacos , Animais , Débito Cardíaco/fisiologia , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Exposição por Inalação/efeitos adversos , Dose Letal Mediana , Profilaxia Pré-Exposição/métodos , Ratos , Ratos Sprague-Dawley , Mecânica Respiratória/fisiologia , Taxa de Sobrevida/tendências
7.
Chem Res Toxicol ; 34(9): 2032-2044, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34427094

RESUMO

Phosphine (PH3) is a highly toxic, corrosive, flammable, heavier-than-air gas that is a commonly used fumigant. When used as a fumigant, PH3 can be released from compressed gas tanks or produced from commercially available metal phosphide tablets. Although the mechanism of toxicity is unclear, PH3 is thought to be a metabolic poison. PH3 exposure induces multiorgan toxicity, and no effective antidotes or therapeutics have been identified. Current medical treatment consists largely of supportive care and maintenance of cardiovascular function. To better characterize the mechanism(s) driving PH3-induced toxicity, we have performed transcriptomic analysis on conscious adult male Sprague-Dawley rats following whole-body inhalation exposure to phosphine gas at various concentration-time products. PH3 exposure induced concentration- and time-dependent changes in gene expression across multiple tissues. These gene expression changes were mapped to pathophysiological responses using molecular pathway analysis. Toxicity pathways indicative of cardiac dysfunction, cardiac arteriopathy, and cardiac enlargement were identified. These cardiotoxic responses were linked to apelin-mediated cardiomyocyte and cardiac fibroblast signaling pathways. Evaluation of gene expression changes in blood revealed alterations in pathways associated with the uptake, transport, and utilization of iron. Altered erythropoietin signaling was also observed in the blood. Upstream regulator analysis identified several therapeutics predicted to counteract PH3-induced gene expression changes. These include antihypertensive drugs (losartan, candesartan, and prazosin) and therapeutics to reduce pathological cardiac remodeling (curcumin and TIMP3). This transcriptomics study has characterized molecular pathways involved in PH3-induced cardiotoxicity. These data will aid in elucidating a precise mechanism of toxicity for PH3 and guide the development of effective medical countermeasures for PH3-induced toxicity.


Assuntos
Praguicidas/toxicidade , Fosfinas/toxicidade , Rodenticidas/toxicidade , Transcriptoma/efeitos dos fármacos , Administração por Inalação , Animais , Anti-Hipertensivos/farmacologia , Apelina/metabolismo , Cardiomegalia/induzido quimicamente , Cardiotônicos/farmacologia , Cardiotoxicidade/genética , Cardiotoxicidade/metabolismo , Coração/efeitos dos fármacos , Masculino , Fosfinas/administração & dosagem , Ratos Sprague-Dawley , Rodenticidas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos
8.
Nicotine Tob Res ; 23(12): 2028-2036, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33984144

RESUMO

INTRODUCTION: The prevalence of light smoking has increased in North America; however, research on the effectiveness of current treatments in this subpopulation of smokers is limited. We compared quit outcomes between light (1-10 cigarettes per day [CPD]) versus heavier smokers (>10 CPD) enrolled in a treatment program at their primary care clinic. AIMS AND METHODS: This secondary analysis analyzed 45 087 participants (light smokers [n = 9861]; heavier smokers [n = 35 226]) enrolled in a smoking cessation program between April 2016 and March 2020. The program offered cost-free nicotine replacement therapy (NRT) plus in-person counseling. Type, dose, and duration of NRT treatment were personalized. Data were collected at baseline, and at 6 months following enrollment to assess 7-day point prevalence abstinence (PPA), the primary outcome variable of interest. Logistic regression models were used for analyses. RESULTS: Seven-day PPA at 6 months was significantly higher among light smokers (30.6%) than heavier smokers (26.0%; odds ratio = 1.25, 95% confidence interval = 1.18-1.33, p < .001). Heavier smokers were prescribed more weeks of NRT than light smokers (B = 0.82, 95% confidence interval = 0.64-1.0, p < .001). The association between smoking cessation and daily NRT dose did not differ between groups (p = .98). However, a stronger positive relationship between the number of clinic visits attended and 7-day PPA was found among heavier smokers in comparison to light smokers (p < .001). All findings remained significant after adjusting for baseline variables. CONCLUSIONS: There is a paucity of scientific literature on the effectiveness of NRT for light smokers. Our findings suggest that individualized doses of NRT may be helpful in these subpopulations, and highlight the different treatment needs of light smokers. IMPLICATIONS: Current clinical guidelines do not provide formal recommendations for light smokers who want to quit smoking. Similar to heavy smokers, light smokers are at substantial risk for many adverse health problems. As such, it is important to understand what treatment options are effective in assisting light smokers to quit smoking. Findings from this study support the use of personalized treatment for all smokers who are interested in quitting smoking, including light smokers.


Assuntos
Abandono do Hábito de Fumar , Humanos , Nicotina , Fumantes , Fumar , Dispositivos para o Abandono do Uso de Tabaco
9.
Plant Foods Hum Nutr ; 76(3): 334-339, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34291371

RESUMO

The blue corn-based products are considered functional foods due to their high concentration of anthocyanins. The aim of this study was to estimate the kinetic and thermodynamic parameters of the thermal degradation of anthocyanins from extruded nixtamalized corn products. A comparative study of anthocyanins thermal stability in these matrices in a buffer solution (pH 2.5) was investigated at different temperatures (60, 75 or 90 °C). Results showed the mechanism of anthocyanins degradation followed first-order reaction kinetics. The values of the reaction rate constant (k) were found to be in a range of 0.027-0.037 h-1 at 60 °C, 0.107-0.113 h-1 at 75 °C and 0.340-0.354 h-1 at 90 °C. The higher the k value was, the shorter the half-life time and D-value. The activation energy (Ea) and z-values were in the range of 75.1-89.2 kJ/mol and 28.8-35.1 °C, respectively. The coefficient Q10 indicated the reaction rate approximately doubles with every 10 °C temperature increase. ∆H, ∆S and ∆G indicated the degradation of anthocyanins was an endothermic and nonspontaneous reaction. Even the major susceptibility of the anthocyanins in extruded nixtamalized corn products at the time-temperature combination applied, there was not difference between flour and tortilla, this imply that most of the anthocyanins were degraded during the nixtamalization extrusion process and no significative further degradation occur in the cooking step. This study provides and advance in the knowledge on the effect of nixtamalization extrusion process and tortillas making on the stability of anthocyanins from blue corn. However, further studies are needed.


Assuntos
Antocianinas , Zea mays , Antocianinas/análise , Manipulação de Alimentos , Cinética , Termodinâmica
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