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1.
Biotechnol Bioeng ; 119(11): 3149-3161, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35959746

RESUMO

Microorganisms build fatty acids with biocatalytic assembly lines, or fatty acid synthases (FASs), that can be repurposed to produce a broad set of fuels and chemicals. Despite their versatility, the product profiles of FAS-based pathways are challenging to adjust without experimental iteration, and off-target products are common. This study uses a detailed kinetic model of the Escherichia coli FAS as a foundation to model nine oleochemical pathways. These models provide good fits to experimental data and help explain unexpected results from in vivo studies. An analysis of pathways for alkanes and fatty acid ethyl esters (FAEEs), for example, suggests that reductions in titer caused by enzyme overexpression-an experimentally consistent phenomenon-can result from shifts in metabolite pools that are incompatible with the substrate specificities of downstream enzymes, and a focused examination of multiple alcohol pathways indicates that coordinated shifts in enzyme concentrations provide a general means of tuning the product profiles of pathways with promiscuous components. The study concludes by integrating all models into a graphical user interface. The models supplied by this work provide a versatile kinetic framework for studying oleochemical pathways in different biochemical contexts.


Assuntos
Escherichia coli , Engenharia Metabólica , Alcanos/metabolismo , Escherichia coli/metabolismo , Ácido Graxo Sintases/metabolismo , Ácidos Graxos/metabolismo , Engenharia Metabólica/métodos
2.
Soc Psychiatry Psychiatr Epidemiol ; 56(11): 2029-2039, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33929549

RESUMO

PURPOSE: No known UK empirical research has investigated prospective associations between ambient air pollutants and conduct problems in adolescence. Ethnic minority children are disproportionately exposed to structural factors that could moderate any observed relationships. This prospective study examined whether exposure to PM2.5 and NO2 concentrations is associated with conduct problems in adolescence, and whether racism or ethnicity moderate such associations. METHODS: Longitudinal associations between annual mean estimated PM2.5 and NO2 concentrations at the residential address and trajectories of conduct problems, and the potential influence of racism and ethnicity were examined school-based sample of 4775 participants (2002-2003 to 2005-2006) in London, using growth curve models. RESULTS: Overall, in the fully adjusted model, exposure to lower concentrations of PM2.5 and NO2 was associated with a decrease in conduct problems during adolescence, while exposure to higher concentrations was associated with a flattened trajectory of conduct symptoms. Racism amplified the effect of PM2.5 (ß = 0.05 (95% CI 0.01 to 0.10, p < 0.01)) on adolescent trajectories of conduct problems over time. At higher concentrations of PM2.5, there was a divergence of trajectories of adolescent conduct problems between ethnic minority groups, with White British and Black Caribbean adolescents experiencing an increase in conduct problems over time. CONCLUSION: These findings suggest that the intersections between air pollution, ethnicity, and racism are important influences on the development of conduct problems in adolescence.


Assuntos
Poluição do Ar , Racismo , Adolescente , Poluição do Ar/efeitos adversos , Criança , Etnicidade , Humanos , Estudos Longitudinais , Grupos Minoritários , Estudos Prospectivos
3.
Am J Physiol Heart Circ Physiol ; 315(3): H463-H473, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29775412

RESUMO

The cardiac extracellular matrix is a complex architectural network that serves many functions, including providing structural and biochemical support to surrounding cells and regulating intercellular signaling pathways. Cardiac function is directly affected by extracellular matrix (ECM) composition, and alterations of the ECM contribute to the progression of heart failure. Initially, collagen deposition is an adaptive response that aims to preserve tissue integrity and maintain normal ventricular function. However, the synergistic effects of proinflammatory and profibrotic responses induce a vicious cycle, which causes excess activation of myofibroblasts, significantly increasing collagen deposition and accumulation in the matrix. Furthermore, excess synthesis and activation of the enzyme lysyl oxidase (LOX) during disease increases collagen cross-linking, which significantly increases collagen resistance to degradation by matrix metalloproteinases (MMPs). In the present study, the aortocaval fistula model of volume overload (VO) was used to determine whether LOX inhibition could prevent adverse changes in the ECM and subsequent cardiac dysfunction. The major findings from this study were that LOX inhibition 1) prevented VO-induced increases in left ventricular wall stress; 2) partially attenuated VO-induced ventricular hypertrophy; 3) completely blocked the increases in fibrotic proteins, including collagens, MMPs, and their tissue inhibitors; and 4) prevented the VO-induced decline in cardiac function. It remains unclear whether a direct interaction between LOX and MMPs exists; however, our experiments suggest a potential link between the two because LOX inhibition completely attenuated VO-induced increases in MMPs. Overall, our study demonstrated key cardioprotective effects of LOX inhibition against adverse cardiac remodeling due to chronic VO. NEW & NOTEWORTHY Although the primary role of lysyl oxidase (LOX) is to cross-link collagens, we found that elevated LOX during cardiac disease plays a key role in the progression of heart failure. Here, we show that inhibition of LOX in volume-overloaded rats prevented the development of cardiac dysfunction and improved ventricular collagen and matrix metalloproteinase/tissue inhibitor of metalloproteinase profiles.


Assuntos
Matriz Extracelular/efeitos dos fármacos , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Miocárdio/metabolismo , Proteína-Lisina 6-Oxidase/antagonistas & inibidores , Aminopropionitrilo/farmacologia , Aminopropionitrilo/uso terapêutico , Animais , Fístula Arteriovenosa/complicações , Colágeno/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Matriz Extracelular/metabolismo , Hipertrofia Ventricular Esquerda/etiologia , Masculino , Metaloproteinases da Matriz/metabolismo , Proteína-Lisina 6-Oxidase/metabolismo , Ratos , Ratos Sprague-Dawley
4.
Alcohol Clin Exp Res ; 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29846943

RESUMO

BACKGROUND: Alcohol is among the most commonly abused drugs worldwide and affects many organ systems, including the heart. Alcoholic cardiomyopathy is characterized by a dilated cardiac phenotype with extensive hypertrophy and extracellular matrix (ECM) remodeling. We have previously shown that chronic ethanol (EtOH) administration accelerates the progression to heart failure in a rat model of volume overload. However, the mechanism by which this decompensation occurs is unknown. For this study, we hypothesized that chronic EtOH administration would prevent compensatory hypertrophy and cardiac remodeling in a rodent model of pressure overload (PO). METHODS: Abdominal aortic constriction was used to create PO in 8-week-old male Wistar rats. Alcohol administration was performed via chronic intermittent EtOH vapor inhalation for 2 weeks prior to surgery and for the duration of the 8-week study. Echocardiography measurements were taken to assess ventricular functional and structural changes. RESULTS: PO increased posterior wall thickness and the hypertrophic markers, atrial and B-type natriuretic peptides (ANP and BNP). With the added stressor of EtOH, wall thickness, ANP, and BNP decreased in PO animals. The combination of PO and EtOH resulted in increased wall stress compared to PO alone. PO also caused increased expression of collagen I and III, whereas EtOH alone only increased collagen III. The combined stresses of PO and EtOH led to an increase in collagen I expression, but collagen III did not change, resulting in an increased collagen I/III ratio in the PO rats treated with EtOH. Lastly, Notch1 expression was significantly increased only in the PO rats treated with EtOH. CONCLUSIONS: Our data indicate that chronic EtOH may limit the cardiac hypertrophy induced by PO which may be associated with a Notch1 mechanism, resulting in increased wall stress and altered ECM profile.

5.
J Mol Cell Cardiol ; 109: 17-26, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28668305

RESUMO

A key feature of heart failure is adverse extracellular matrix (ECM) remodeling, which is associated with increases in the collagen cross-linking enzyme, lysyl oxidase (LOX). In this study, we assess the progression of cardiovascular remodeling from the compensatory to decompensatory phase, with a focus on the change in LOX expression and activity as it relates to alterations in ECM composition and changes in cardiac function. Adult male Sprague-Dawley rats were studied after 4, 14, or 21weeks of aortocaval fistula-induced volume overload (VO). Progressive increases in the left and right ventricular mass indicated biventricular hypertrophy. Echocardiography revealed significant increases in the posterior wall thickness and internal diameter of the left ventricle as early as 3weeks, which persisted until the 21week endpoint. There were also significant decreases in eccentric index and fractional shortening in VO animals. Hemodynamic measurements showed progressive decreases in contractility, indicative of systolic dysfunction. There were progressive VO-induced increases in LOX expression and activity, collagen, and collagen cross-linking during the course of these experiments. We observed a negative correlation between LOX activity and cardiac function. Additional rats were treated with an inhibitor of LOX activity starting at 2weeks post-surgery and continued to 14weeks. LOX inhibition prevented the cardiac dysfunction and collagen accumulation caused by VO. Overall these data suggest a detrimental role for the chronic increase of cardiac LOX expression and activity in the transition from compensated remodeling to decompensated failure.


Assuntos
Regulação Enzimológica da Expressão Gênica , Insuficiência Cardíaca/enzimologia , Contração Miocárdica , Miocárdio/enzimologia , Proteína-Lisina 6-Oxidase/metabolismo , Remodelação Ventricular , Animais , Ecocardiografia , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Masculino , Miocárdio/patologia , Ratos , Ratos Sprague-Dawley
6.
J Mol Cell Cardiol ; 97: 15-23, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27107489

RESUMO

Chronic alcohol abuse is one of the leading causes of dilated cardiomyopathy (DCM) in the United States. Volume overload (VO) also produces DCM characterized by left ventricular (LV) dilatation and reduced systolic and diastolic function, eventually progressing to congestive heart failure. For this study, we hypothesized that chronic alcohol exposure would exacerbate cardiac dysfunction and remodeling due to VO. Aortocaval fistula surgery was used to induce VO, and compensatory cardiac remodeling was allowed to progress for either 3days (acute) or 8weeks (chronic). Alcohol was administered via chronic intermittent ethanol vapor (EtOH) for 2weeks before the acute study and for the duration of the 8week chronic study. Temporal alterations in LV function were assessed by echocardiography. At the 8week end point, pressure-volume loop analysis was performed by LV catheterization and cardiac tissue collected. EtOH did not exacerbate LV dilatation (end-systolic and diastolic diameter) or systolic dysfunction (fractional shortening, ejection fraction) due to VO. The combined stress of EtOH and VO decreased the eccentric index (posterior wall thickness to end-diastolic diameter ratio), increased end-diastolic pressure (EDP), and elevated diastolic wall stress. VO also led to increases in posterior wall thickness, which was not observed in the VO+EtOH group, and wall thickness significantly correlated with LV BNP expression. VO alone led to increases in interstitial collagen staining (picrosirius red), which while not statistically significant, tended to be decreased by EtOH. VO increased LV collagen I protein expression, whereas in rats with VO+EtOH, LV collagen I was not elevated relative to Sham. The combination of VO and EtOH also led to increases in LV collagen III expression relative to Sham. Rats with VO+EtOH had significantly lower collagen I/III ratio than rats with VO alone. During the acute remodeling phase of VO (3days), VO significantly increased collagen III expression, whereas this effect was not observed in rats with VO+EtOH. In conclusion, chronic EtOH accelerates the development of elevated wall stress and promotes early eccentric remodeling in rats with VO. Our data indicate that these effects may be due to disruptions in compensatory hypertrophy and extracellular matrix remodeling in response to volume overload.


Assuntos
Álcoois/efeitos adversos , Miocárdio/metabolismo , Miocárdio/patologia , Remodelação Ventricular , Consumo de Bebidas Alcoólicas , Álcoois/administração & dosagem , Animais , Biomarcadores , Cardiomiopatias/diagnóstico , Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Cardiomiopatias/mortalidade , Colágeno/genética , Colágeno/metabolismo , Modelos Animais de Doenças , Ecocardiografia , Matriz Extracelular/metabolismo , Expressão Gênica , Masculino , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , Isoformas de Proteínas , Proteína-Lisina 6-Oxidase/genética , Proteína-Lisina 6-Oxidase/metabolismo , Ratos , Função Ventricular Esquerda
7.
J Hepatol ; 65(1): 57-65, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26988732

RESUMO

BACKGROUND & AIMS: Acute-on-chronic liver failure (ACLF) is a syndrome that occurs in cirrhosis characterized by organ failure(s) and high mortality rate. There are no biomarkers of ACLF. The LCN2 gene and its product, neutrophil gelatinase-associated lipocalin (NGAL), are upregulated in experimental models of liver injury and cultured hepatocytes as a result of injury by toxins or proinflammatory cytokines, particularly Interleukin-6. The aim of this study was to investigate whether NGAL could be a biomarker of ACLF and whether LCN2 gene may be upregulated in the liver in ACLF. METHODS: We analyzed urine and plasma NGAL levels in 716 patients hospitalized for complications of cirrhosis, 148 with ACLF. LCN2 expression was assessed in liver biopsies from 29 additional patients with decompensated cirrhosis with and without ACLF. RESULTS: Urine NGAL was markedly increased in ACLF vs. no ACLF patients (108(35-400) vs. 29(12-73)µg/g creatinine; p<0.001) and was an independent predictive factor of ACLF; the independent association persisted after adjustment for kidney function or exclusion of variables present in ACLF definition. Urine NGAL was also an independent predictive factor of 28day transplant-free mortality together with MELD score and leukocyte count (AUROC 0.88(0.83-0.92)). Urine NGAL improved significantly the accuracy of MELD in predicting prognosis. The LCN2 gene was markedly upregulated in the liver of patients with ACLF. Gene expression correlated directly with serum bilirubin and INR (r=0.79; p<0.001 and r=0.67; p<0.001), MELD (r=0.68; p<0.001) and Interleukin-6 (r=0.65; p<0.001). CONCLUSIONS: NGAL is a biomarker of ACLF and prognosis and correlates with liver failure and systemic inflammation. There is remarkable overexpression of LCN2 gene in the liver in ACLF syndrome. LAY SUMMARY: Urine NGAL is a biomarker of acute-on-chronic liver failure (ACLF). NGAL is a protein that may be expressed in several tissues in response to injury. The protein is filtered by the kidneys due to its small size and can be measured in the urine. Ariza, Graupera and colleagues found in a series of 716 patients with cirrhosis that urine NGAL was markedly increased in patients with ACLF and correlated with prognosis. Moreover, gene coding NGAL was markedly overexpressed in the liver tissue in ACLF.


Assuntos
Insuficiência Hepática Crônica Agudizada , Injúria Renal Aguda , Biomarcadores , Humanos , Lipocalina-2 , Cirrose Hepática , Prognóstico
8.
Phys Rev Lett ; 114(6): 062002, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25723208

RESUMO

The COMPASS collaboration at CERN has investigated pion Compton scattering, π(-)γ→π(-)γ, at center-of-mass energy below 3.5 pion masses. The process is embedded in the reaction π(-)Ni→π(-)γNi, which is initiated by 190 GeV pions impinging on a nickel target. The exchange of quasireal photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, Q(2)<0.0015 (GeV/c)(2). From a sample of 63,000 events, the pion electric polarizability is determined to be α(π)=(2.0±0.6(stat)±0.7(syst))×10(-4) fm(3) under the assumption α(π)=-ß(π), which relates the electric and magnetic dipole polarizabilities. It is the most precise measurement of this fundamental low-energy parameter of strong interaction that has been addressed since long by various methods with conflicting outcomes. While this result is in tension with previous dedicated measurements, it is found in agreement with the expectation from chiral perturbation theory. An additional measurement replacing pions by muons, for which the cross-section behavior is unambiguously known, was performed for an independent estimate of the systematic uncertainty.

9.
Alcohol Clin Exp Res ; 38(2): 448-56, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24033327

RESUMO

BACKGROUND: Chronic alcohol consumption has been shown in human and animal studies to result in collagen accumulation, myocardial fibrosis, and heart failure. Cardiac fibroblasts produce collagen and regulate extracellular matrix (ECM) homeostasis through the synthesis and activity of matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs), with the balance of MMPs/TIMPs determining the rate of collagen turnover. Dynamic changes of MMP and TIMP expression were reported in alcohol-induced hepatic fibrosis; however, the effect of alcohol on MMP/TIMP balance in the heart and cardiac fibroblasts is unknown. We hypothesized that alcohol exposure alters cardiac fibroblast MMP and TIMP expression to promote collagen accumulation in the heart. METHODS: Cardiac fibroblasts isolated from adult rats were cultured in the presence of alcohol (12.5 to 200 mM) for 48 hours. MMP, TIMP, and collagen type I and III expression were assayed by Western blot analysis. Hydroxyproline (HPro) was used as a marker of collagen production. The in vivo cardiac effects of ethanol (EtOH) were determined using rats exposed to EtOH vapor for 2 weeks, resulting in blood alcohol levels of 150 to 200 mg/dl. Cardiac collagen volume fraction (CVF), as well as MMP, TIMP, and collagen expression, was assessed. RESULTS: EtOH-exposed rats exhibited up-regulation of TIMP-1, TIMP-3 and TIMP-4 in the heart, with no significant increases in MMPs. Cardiac fibroblasts exhibited transformation to a profibrotic phenotype following exposure to alcohol. These changes were reflected by increased α-smooth muscle actin and collagen I and III expression, as well as increased collagen secretion. In vivo EtOH exposure also produced fibrosis, indicated by increased CVF and expression of collagens. CONCLUSIONS: Alcohol exposure modulates cardiac fibroblast MMP/TIMP expression favoring a profile associated with collagen accumulation. Our data suggest that this disrupted MMP/TIMP profile may contribute to the development of myocardial fibrosis and cardiac dysfunction resulting from chronic alcohol abuse.


Assuntos
Depressores do Sistema Nervoso Central/farmacologia , Colágeno/metabolismo , Etanol/farmacologia , Coração/efeitos dos fármacos , Metaloproteinases da Matriz/metabolismo , Miocárdio/enzimologia , Inibidores Teciduais de Metaloproteinases/metabolismo , Actinas/metabolismo , Alcoolismo/enzimologia , Alcoolismo/patologia , Animais , Western Blotting , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Fibroblastos/metabolismo , Fibrose , Hidroxiprolina/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
10.
Int J Sports Med ; 35(2): 164-71, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23868679

RESUMO

In order to compare the effects of leisure physical activity (LPA), aerobic training (AT) and aerobic plus resistance training (AT + RT) as part of a 6-month interdisciplinary therapy in body composition, insulin resistance and leptin concentrations in obese adolescents, 72 volunteers (n = 24 in each group) ages 15-19 years were evaluated. Delta (Δ) body mass (kg) and Δ BMI (kg/m(2)) was different between AT and LPA groups and in AT + RT group compared to both LPA and AT groups; Δ body fat mass (kg and %) was different only in AT + RT group compared to both LPA and AT; Δ body lean mass (%) was different only in AT + RT group; Δ body lean mass (kg) was negative only in AT and positive and different from AT in AT + RT group; ΔHOMA-IR did not differ among groups; Δ leptin (ng/ml) was negative and different from LPA for both AT and AT + RT groups. In conclusion, both AT and AT + RT promoted a reduction on leptin levels, however, the adolescents subjected to AT + RT presented better results in body composition than the AT group. These results highlight the importance of associating aerobic and resistance training with nutritional and psychological approaches in the treatment of obese adolescents.


Assuntos
Leptina/sangue , Obesidade/sangue , Condicionamento Físico Humano/fisiologia , Treinamento Resistido , Adolescente , Composição Corporal , Índice de Massa Corporal , Peso Corporal , Dieta , Ingestão de Energia , Feminino , Humanos , Resistência à Insulina , Atividades de Lazer , Masculino , Atividade Motora/fisiologia , Obesidade/psicologia , Educação de Pacientes como Assunto , Adulto Jovem
11.
J Sports Med Phys Fitness ; 54(6): 809-15, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25350038

RESUMO

AIM: Aim of the study was to determine which factors influence sleep patterns after a single session of physical exercise. METHODS: Adult sedentary volunteers (N.=221; 104 men and 117 women) aged 31.40±9.40 were randomised into groups with three different types of physical exercise (resistance, aerobic and interval). After the exercise protocol was explained, each volunteer was given the first polysomnographic (PSG) and performed the acute session of physical exercise (resistance: based on a 1RM test; aerobic: based on a maximum effort test (MET) and interval: 10 series with 4-minute intervals between series). The second PSG was performed the day after the acute session of physical exercise. RESULTS: A negative correlation was found between sleep latency and the acute physical exercise session practiced in the evening, and a positive correlation was found between the total sleep time and female gender. The REM sleep stage (%) was positively correlated with the control, obstructive sleep apnea (OSA) and periodic leg movement (PLM) groups and the acute physical exercise session practiced in the morning. Positive correlations were observed in the arousal index and the PLM group and female gender; the PLM index and the control and OSA groups; minimum oxygen saturation and the OSA and PLM groups. CONCLUSION: Therefore, these results suggested that such factors as gender, the presence of sleep disturbance (PLM and/or OSA), type of physical exercise (aerobic, resistance or interval) and the time that it was practiced (morning, afternoon or evening) can influence sleep patterns after a single session of physical exercise. However, the gender seems to be the most important factor to influence sleep pattern in the situation studied.


Assuntos
Exercício Físico , Fases do Sono , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Adulto Jovem
12.
Clin Neurophysiol ; 158: 35-42, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38150916

RESUMO

OBJECTIVE: This longitudinal study aims at assessing the predictive value of facial nerve high-resolution ultrasound (HRUS) for incomplete clinical recovery in patients with Bell's palsy, the most common facial nerve disease. METHODS: We prospectively enrolled 34 consecutive patients with Bell's palsy. All patients underwent neurophysiological testing (including facial nerve conduction study) and HRUS evaluations 10-15 days (T1), one month (T2), and three months (T3) after the onset of Bell's palsy. Patients who did not experience complete recovery within three months were also evaluated after six months (T4). We have then compared the accuracy of HRUS with that of the facial nerve conduction study in predicting incomplete clinical recovery at three and six months. RESULTS: At T1, the facial nerve diameter, as assessed with HRUS, was larger on the affected side than on the normal side, particularly in patients with incomplete recovery at T2, T3 and T4. ROC curve analysis, however, showed that the facial nerve diameter at T1 had a lower predictive value than the facial nerve conduction study for an incomplete clinical recovery at three (T3) and six (T4) months. Still, the facial nerve diameter asymmetry, as assessed with HRUS, had a relatively high negative predictive value (thus indicating a strong association between normal HRUS examination and a good prognosis). CONCLUSIONS: Although HRUS shows abnormally increased facial nerve diameter in patients in the acute phase of Bell's palsy, the predictive value of this technique for incomplete clinical recovery at three and six months is lower than that of the nerve conduction study. SIGNIFICANCE: Nerve ultrasound has a low predictive value for incomplete clinical recovery in patients with Bell's Palsy.


Assuntos
Paralisia de Bell , Paralisia Facial , Humanos , Paralisia de Bell/diagnóstico por imagem , Nervo Facial/diagnóstico por imagem , Estudos de Condução Nervosa , Estudos Longitudinais
13.
PLoS One ; 18(2): e0279719, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36753491

RESUMO

Longitudinal evidence on the association between air pollution and blood pressure (BP) in adolescence is scarce. We explored this association in an ethnically diverse cohort of schoolchildren. Sex-stratified, linear random-effects modelling was used to examine how modelled residential exposure to annual average nitrogen dioxide (NO2), particulate matter (PM2.5, PM10) and ozone (O3), measures in µg/m3, associated with blood pressure. Estimates were based on 3,284 adolescents; 80% from ethnic minority groups, recruited from 51 schools, and followed up from 11-13 to 14-16 years old. Ethnic minorities were exposed to higher modelled annual average concentrations of pollution at residential postcode level than their White UK peers. A two-pollutant model (NO2 & PM2.5), adjusted for ethnicity, age, anthropometry, and pubertal status, highlighted associations with systolic, but not diastolic BP. A µg/m3 increase in NO2 was associated with a 0.30 mmHg (95% CI 0.18 to 0.40) decrease in systolic BP for girls and 0.19 mmHg (95% CI 0.07 to 0.31) decrease in systolic BP for boys. In contrast, a 1 µg/m3 increase in PM2.5 was associated with 1.34 mmHg (95% CI 0.85 to 1.82) increase in systolic BP for girls and 0.57 mmHg (95% CI 0.04 to 1.03) increase in systolic BP for boys. Associations did not vary by ethnicity, body size or socio-economic advantage. Associations were robust to adjustments for noise levels and lung function at 11-13 years. In summary, higher ambient levels of NO2 were associated with lower and PM2.5 with higher systolic BP across adolescence, with stronger associations for girls.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Masculino , Feminino , Humanos , Adolescente , Criança , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Pressão Sanguínea , Dióxido de Nitrogênio/análise , Londres , Etnicidade , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Grupos Minoritários , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Material Particulado/efeitos adversos , Material Particulado/análise , Ozônio/efeitos adversos , Ozônio/análise , Inglaterra/epidemiologia
14.
Phys Rev Lett ; 108(19): 192001, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-23003028

RESUMO

The COMPASS Collaboration at CERN has investigated the π- γ → π- π- π+ reaction at center-of-momentum energy below five pion masses, sqrt[s]<5m(π), embedded in the Primakoff reaction of 190 GeV pions impinging on a lead target. Exchange of quasireal photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, t'<0.001 GeV2/c2. Using partial-wave analysis techniques, the scattering intensity of Coulomb production described in terms of chiral dynamics and its dependence on the 3π-invariant mass m(3π)=sqrt[s] were extracted. The absolute cross section was determined in seven bins of sqrt[s] with an overall precision of 20%. At leading order, the result is found to be in good agreement with the prediction of chiral perturbation theory over the whole energy range investigated.

15.
Nat Commun ; 13(1): 3998, 2022 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-35810180

RESUMO

Basic processes of the fatty acid metabolism have an important impact on the function of intestinal epithelial cells (IEC). However, while the role of cellular fatty acid oxidation is well appreciated, it is not clear how de novo fatty acid synthesis (FAS) influences the biology of IECs. We report here that interfering with de novo FAS by deletion of the enzyme Acetyl-CoA-Carboxylase (ACC)1 in IECs results in the loss of epithelial crypt structures and a specific decline in Lgr5+ intestinal epithelial stem cells (ISC). Mechanistically, ACC1-mediated de novo FAS supports the formation of intestinal organoids and the differentiation of complex crypt structures by sustaining the nuclear accumulation of PPARδ/ß-catenin in ISCs. The dependency of ISCs on cellular de novo FAS is tuned by the availability of environmental lipids, as an excess delivery of external fatty acids is sufficient to rescue the defect in crypt formation. Finally, inhibition of ACC1 reduces the formation of tumors in colitis-associated colon cancer, together highlighting the importance of cellular lipogenesis for sustaining ISC function and providing a potential perspective to colon cancer therapy.


Assuntos
Acetil-CoA Carboxilase , Lipogênese , Acetilcoenzima A/metabolismo , Acetil-CoA Carboxilase/metabolismo , Ácidos Graxos/metabolismo , Lipogênese/fisiologia , Células-Tronco/metabolismo
16.
J Exp Med ; 219(10)2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-35938981

RESUMO

Epigenetic modifications such as DNA methylation play an essential role in imprinting specific transcriptional patterns in cells. We performed genome-wide DNA methylation profiling of murine lymph node-derived ILCs, which led to the identification of differentially methylated regions (DMRs) and the definition of epigenetic marker regions in ILCs. Marker regions were located in genes with a described function for ILCs, such as Tbx21, Gata3, or Il23r, but also in genes that have not been related to ILC biology. Methylation levels of the marker regions and expression of the associated genes were strongly correlated, indicating their functional relevance. Comparison with T helper cell methylomes revealed clear lineage differences, despite partial similarities in the methylation of specific ILC marker regions. IL-33-mediated challenge affected methylation of ILC2 epigenetic marker regions in the liver, while remaining relatively stable in the lung. In our study, we identified a set of epigenetic markers that can serve as a tool to study phenotypic and functional properties of ILCs.


Assuntos
Imunidade Inata , Linfócitos , Animais , Biomarcadores , Metilação de DNA/genética , Epigênese Genética , Estudo de Associação Genômica Ampla , Camundongos
17.
Minerva Gastroenterol Dietol ; 57(2): 111-5, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21587142

RESUMO

AIM: Endoscopic variceal ligation (EVL) is recommended for the treatment of esophageal variceal bleeding. The aim of this study was to assess the most cost-effective timing of endoscopic follow-up after variceal eradication. METHODS: Cirrhotics with esophageal varices treated between January 2008 and January 2009 until reached variceal obliteration were retrospectively analyzed for technical aspects and for outcomes. RESULTS: Out of 127 patients treated with EVL, 103 were included. Number of sessions to achieve variceal obliteration and number of bands for each session were 2.8±1.3 (range 1-7) and 4.6±1 (range 2-7), respectively. The placement of >5 bands per session was not associated with higher incidence of complications (19.6% vs. 17.8%, P=ns). Esophageal ulcers were observed in 42% of patients when the interbanding interval was <20 days (versus 15% for interval >20 days, P<0.05). Once obliteration was achieved, varices reappeared in 28% of patients; the early appearance of small varices was not associated with bleeding. CONCLUSION: A longer interbanding interval reduces the incidence of procedural-related complications. After variceal obliteration an early endoscopic control is not useful because it does not influence the approach and does not change the patient outcome.


Assuntos
Varizes Esofágicas e Gástricas/cirurgia , Esofagoscopia , Hemorragia Gastrointestinal/cirurgia , Cirrose Hepática/complicações , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/etiologia , Esofagoscopia/métodos , Hemorragia Gastrointestinal/etiologia , Humanos , Ligadura/métodos , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
18.
J Am Heart Assoc ; 10(21): e022930, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34713711

RESUMO

Background Obesity is associated with heart failure with preserved ejection fraction (HFpEF). Weight loss can improve exercise capacity in HFpEF. However, previously reported methods of weight loss are impractical for widespread clinical implementation. We tested the hypothesis that an intensive lifestyle modification program would lead to relevant weight loss and improvement in functional status in patients with HFpEF and obesity. Methods and Results Patients with ejection fraction >45%, at least 1 objective criteria for HFpEF, and body mass index ≥30 kg/m2 were offered enrollment in an established 15-week weight management program that included weekly visits for counseling, weight checks, and provision of meal replacements. At baseline, 15 weeks, and 26 weeks, Minnesota Living With Heart Failure score, 6-minute walk distance, echocardiography, and laboratory variables were assessed. A total of 41 patients completed the study (mean body mass index, 40.8 kg/m2), 74% of whom lost >5% of their baseline body weight following the 15-week program. At 15 weeks, mean 6-minute walk distance increased from 223 to 281 m (P=0.001) and then decreased to 267 m at 26 weeks. Minnesota Living With Heart Failure score improved from 59.9 to 37.3 at 15 weeks (P<0.001) and 37.06 at 26 weeks. Changes in weight correlated with change in Minnesota Living With Heart Failure score (r=0.452; P=0.000) and 6-minute walk distance (r=-0.388; P<0.001). Conclusions In a diverse population of patients with obesity and HFpEF, clinically relevant weight loss can be achieved with a pragmatic 15-week program. This is associated with significant improvements in quality of life and exercise capacity. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02911337.


Assuntos
Insuficiência Cardíaca , Programas de Redução de Peso , Tolerância ao Exercício , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Humanos , Obesidade/complicações , Obesidade/diagnóstico , Obesidade/terapia , Qualidade de Vida , Volume Sistólico , Redução de Peso
19.
J Urol ; 184(3): 1028-33, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20643426

RESUMO

PURPOSE: We evaluated urinary continence using a validated questionnaire in a series of consecutive patients who underwent robot assisted laparoscopic radical prostatectomy, and identified the preoperative predictors of the return to urinary continence. MATERIALS AND METHODS: The clinical records of 308 consecutive patients who underwent robot assisted laparoscopic radical prostatectomy for clinically localized prostate cancer at a tertiary academic center were prospectively collected. All patients were continent before surgery. Urinary continence was evaluated using the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form instrument. All of the patients reporting no leak in response to the question, "How often do you leak urine?" were defined as continent. RESULTS: A total of 273 patients (90%) were continent 12 months after robot assisted laparoscopic radical prostatectomy. Continent patients were significantly younger (61.4 +/- 6.4 vs 64.1 +/- 6.1 years, p = 0.02) than those who were incontinent. On univariable regression analysis patient age at surgery (OR 1.075, p = 0.024) and Charlson comorbidity index (OR 1.671, p = 0.007) were significantly associated with 12-month continence status. On multivariable analysis age (OR 1.076, p = 0.027) and Charlson comorbidity index (OR 1.635, p = 0.009) were independent predictors of continence rates. CONCLUSIONS: Using the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form 90% of patients undergoing robot assisted laparoscopic radical prostatectomy reported no urine leak 12 months after surgery. Patient age at surgery and Charlson comorbidity index were independent predictors of the return to urinary continence, whereas notably no variable related to prostate cancer was significantly correlated with urinary continence.


Assuntos
Laparoscopia , Prostatectomia/métodos , Robótica , Inquéritos e Questionários , Incontinência Urinária/diagnóstico , Incontinência Urinária/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
20.
Minerva Med ; 101(2): 121-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20467411

RESUMO

Over the past fifteen years, numerous observations have linked Helicobacter pylori (H. pylori) infection to ischemic heart disease (IHD). Despite the controversial literature data, it has been postulated that if a role is plausible, it will be in the early events of the acute coronary syndrome. According to this model, we focused on the potential pathogenic mechanisms relating H. pylori to IHD like platelet aggregation and thrombosis. To identify all publications in this field, a MEDLINE search of studies published in English from 1965 to 2009 was conducted. Although very few investigations were found, these showed data of paramount importance. In particular, it has been demonstrated that some strains of H. pylori bind von Willebrand factor and interact with glycoprotein Ib to induce platelet aggregation in humans. In experiments from animal models, such infection promoted the formation of platelet aggregates by both a marked increase in the flux of rolling leukocytes and the appearance of platelet and leukocyte-platelet aggregates in gastric venules. This aggregate formation was abrogated by antibodies against specific adhesion molecules (L- and P-selectin). The future challenge is to gain more knowledge in this field and to translate these information into clinical practice.


Assuntos
Infecções por Helicobacter/complicações , Helicobacter pylori/patogenicidade , Isquemia Miocárdica/microbiologia , Trombose/microbiologia , Doença da Artéria Coronariana/microbiologia , Humanos , Infarto do Miocárdio/microbiologia , Agregação Plaquetária/fisiologia , Fatores de Risco
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