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1.
Eur Heart J ; 43(26): 2496-2507, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35139531

RESUMO

AIMS: To evaluate the impact of a simplified, rapid cardiovascular magnetic resonance (CMR) protocol embedded in care and supported by a partner education programme on the management of cardiomyopathy (CMP) in low- and middle-income countries (LMICs). METHODS AND RESULTS: Rapid CMR focused particularly on CMP was implemented in 11 centres, 7 cities, 5 countries, and 3 continents linked to training courses for local professionals. Patients were followed up for 24 months to assess impact. The rate of subsequent adoption was tracked. Five CMR conferences were delivered (920 attendees-potential referrers, radiographers, reporting cardiologists, or radiologists) and five new centres starting CMR. Six hundred and one patients were scanned. Cardiovascular magnetic resonance indications were 24% non-contrast T2* scans [myocardial iron overload (MIO)] and 72% suspected/known cardiomyopathies (including ischaemic and viability). Ninety-eighty per cent of studies were of diagnostic quality. The average scan time was 22 ± 6 min (contrast) and 12 ± 4 min (non-contrast), a potential cost/throughput reduction of between 30 and 60%. Cardiovascular magnetic resonance findings impacted management in 62%, including a new diagnosis in 22% and MIO detected in 30% of non-contrast scans. Nine centres continued using rapid CMR 2 years later (typically 1-2 days per week, 30 min slots). CONCLUSIONS: Rapid CMR of diagnostic quality can be delivered using available technology in LMICs. When embedded in care and a training programme, costs are lower, care is improved, and services can be sustained over time.


Assuntos
Cardiomiopatias , Sobrecarga de Ferro , Cardiomiopatias/diagnóstico por imagem , Monofosfato de Citidina , Países em Desenvolvimento , Humanos , Imageamento por Ressonância Magnética/métodos , Imagem Cinética por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética
2.
Org Biomol Chem ; 20(12): 2462-2466, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35258067

RESUMO

The breakdown of O,O-diethyl-2,4-dinitrophenyl phosphate in formamide (FMD) solutions is assessed using kinetic studies and 31P nuclear magnetic resonance (NMR) analysis. Regiospecific nucleophilic amidolysis via P-O bond cleavage is observed, leading to non-toxic diester and FMD regeneration. In the systems evaluated, water plays an antagonistic role: while it is key for the breakdown of the reaction intermediate, it inhibits the nucleophilic activity of FMD by hydrogen bonding effects.


Assuntos
Fosfatos , Água , Cinética , Espectroscopia de Ressonância Magnética , Organofosfatos/química , Fosfatos/química , Água/química
3.
Trop Anim Health Prod ; 54(5): 294, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36098820

RESUMO

The objective of this study was to determine the correlation between ingestive behavior, apparent digestibility, and residual feed intake (RFI) of finishing Nellore bulls fed a high concentrate diet. One hundred and twenty Nellore bulls, housed in individual pens, were evaluated in individual performance tests. The animals were fed a high concentrate diet (23:77 roughage/concentrate ratio). The animals were classified as low RFI, medium RFI, and high RFI. Data from ten animals from each group were used. Fecal production and nutrient digestibility were calculated using indigestible neutral detergent fiber as an internal marker. The feeding behavior was evaluated over 24 h by direct observation every 5 min. The most efficient animals (low RFI, 8.58 kg DM/day) consumed 27.62% less feed than the least efficient animals (high RFI, 10.95 kg DM/day). Animals with medium efficiency (mean RFI, 9.49 kg DM/day) consumed 15.39% less than high RFI. Nutrient digestibility coefficients were similar except for ether extract (P < 0.03) which was 8% greater for the high-RFI animals. No effect was observed for ingestive behavior (P > 0.05). Animals spent, on average, 3 h 28 min feeding, 7 h 32 min ruminating, and 13 h 40 min in idle time. In the present study, ingestive behavior and dry matter digestibility were not responsible for between-animal variation in residual feed intake in Nellore bulls fed a high concentrate diet.


Assuntos
Ração Animal , Digestão , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Fibras na Dieta , Ingestão de Alimentos , Comportamento Alimentar , Masculino
4.
Vox Sang ; 116(8): 887-897, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33634883

RESUMO

BACKGROUND AND OBJECTIVES: Iron overload in thalassaemia is a crucial prognostic factor and a major cause of death due to heart failure or arrhythmia. Therefore, previous research has recommended amlodipine as an auxiliary treatment to current chelating agents for reducing iron overload in thalassaemia patients. MATERIALS AND METHODS: A systematic review and meta-analysis of the results of three randomized clinical trials evaluating the use of amlodipine in thalassaemia patients through 12 databases were carried out. RESULTS: Our final cohort included 130 patients. Insignificant difference in decreasing liver iron concentrations was found between amlodipine and control groups {weighted mean difference = -0·2, [95% confidence interval = (-0·55-0·15), P = 0·26]}. As regards serum ferritin, our analysis also showed no significant difference in serum ferritin between amlodipine and control groups {weighted mean difference [95% confidence interval = -0·16 (-0·51-0·19), P = 0·36]}. Similarly, there was insignificant difference in cardiac T2* between amlodipine and control groups {weighted mean difference [95% confidence interval = 0·34 (-0·01-0·69), P = 0·06]}. CONCLUSIONS: Despite the growing evidence supporting the role of amlodipine in reducing iron overload in thalassaemia patients, our meta-analysis did not find that evidence collectively significant. The results of our simulation suggest that when more data are available, a meta-analysis with more randomized clinical trials could provide more conclusive insights.


Assuntos
Sobrecarga de Ferro , Talassemia , Talassemia beta , Anlodipino/uso terapêutico , Humanos , Quelantes de Ferro , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Talassemia/tratamento farmacológico
5.
J Org Chem ; 86(5): 4027-4034, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33587642

RESUMO

Organophosphate (OP) pesticides are responsible for numerous human deaths every year. Nucleophilic substitution is an important method to mitigate the toxicity of obsolete stocks of OPs. Herein, the degradation of O,O-diethyl-2,4-dinitrophenyl phosphate (DEDNPP) and pesticide diethyl-4-nitrophenyl phosphate (Paraoxon) promoted by 1,2,4-triazole (TAZ) was investigated by means of kinetic studies, nuclear magnetic resonance (NMR) analyses, and theoretical calculations. Results showed fast degradation of OPs is promoted by the anionic form of the nucleophile (TAZ(-)) in pH > 8.5 (optimal at pH = 11). Rate enhancements of 106 and 105-fold in relation to neutral hydrolysis of DEDNPP and Paraoxon were observed, respectively, consistent with alpha-nucleophiles reactivity. TAZ(-) regioselectively promotes the degradation of DEDNPP via P-O bond break, forming a quickly hydrolyzable phosphorylated intermediate, regenerating the nucleophile. Calculations using M06-2X/6-311++G(d,p) level of theory revealed that the equivalent nitrogen atoms of TAZ(-) are the main nucleophilic center of the molecule. This study expands the knowledge on the reactivity of iminic compounds as detoxificant agents of OPs, indicating the efficiency and selectivity of TAZ(-) in aqueous medium, encouraging the design of novel TAZ-based catalysts.


Assuntos
Organofosfatos , Paraoxon , Ânions , Humanos , Hidrólise , Cinética , Triazóis
6.
J Cardiovasc Magn Reson ; 23(1): 52, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33966639

RESUMO

This document is a position statement from the Society for Cardiovascular Magnetic Resonance (SCMR) on recommendations for clinical utilization of cardiovascular magnetic resonance (CMR) in women with cardiovascular disease. The document was prepared by the SCMR Consensus Group on CMR Imaging for Female Patients with Cardiovascular Disease and endorsed by the SCMR Publications Committee and SCMR Executive Committee. The goals of this document are to (1) guide the informed selection of cardiovascular imaging methods, (2) inform clinical decision-making, (3) educate stakeholders on the advantages of CMR in specific clinical scenarios, and (4) empower patients with clinical evidence to participate in their clinical care. The statements of clinical utility presented in the current document pertain to the following clinical scenarios: acute coronary syndrome, stable ischemic heart disease, peripartum cardiomyopathy, cancer therapy-related cardiac dysfunction, aortic syndrome and congenital heart disease in pregnancy, bicuspid aortic valve and aortopathies, systemic rheumatic diseases and collagen vascular disorders, and cardiomyopathy-causing mutations. The authors cite published evidence when available and provide expert consensus otherwise. Most of the evidence available pertains to translational studies involving subjects of both sexes. However, the authors have prioritized review of data obtained from female patients, and direct comparison of CMR between women and men. This position statement does not consider CMR accessibility or availability of local expertise, but instead highlights the optimal utilization of CMR in women with known or suspected cardiovascular disease. Finally, the ultimate goal of this position statement is to improve the health of female patients with cardiovascular disease by providing specific recommendations on the use of CMR.


Assuntos
Doenças Cardiovasculares , Cardiopatias Congênitas , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/terapia , Feminino , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Valor Preditivo dos Testes
7.
J Anim Physiol Anim Nutr (Berl) ; 105(4): 639-652, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33559351

RESUMO

The effects of doses CTL (0 mg), 30, 300 and 3000 mg/L of extracts from Stryphnodendron adstringens (Mart.) Coville (SA), Lafoensia pacari A. St.-Hil (LP), Copaifera spp. (CO) and Pterodon emarginatus Vogel (PE) on ruminal fermentation were investigated in eight experiments conducted in randomized complete block designs. The in vitro system contained four fermentation vessels. Each treatment was allocated in one vessel in each run. Incubation was run four and five times with diets 50:50 and 10:90 (roughage to concentrate ratio) respectively. Incubation vessel was the experimental unit, and each incubation run was a block. All plant extracts negatively affected DM degradation at 3000 mg/L. In diet 50:50, SA-3000 increased the molar proportion of propionate (p < 0.05), yet it decreased the concentration of fermentation products (p < 0.05); LP-300 reduced ruminal ammonia nitrogen (NH3 -N; 98 vs. 120 mg/dl for LP-300 and average of CTL and LP-30, respectively) and isobutyrate (p < 0.05); CO-300 reduced (p < 0.05) NH3 -N (98 vs. 123 mg/dl for CO-300 and average of CTL and CO-30, respectively); and P. emarginatus had no positive effects on rumen fermentation (p > 0.05). In diet 10:90, SA-300 reduced (p < 0.001) NH3 -N and total volatile fatty acids (VFA); LP-30 increased (p < 0.05) total VFA (85 vs. 63 mM for LP-30 and CTL, respectively), molar proportions of acetate and propionate, and had lower C2 :C3 than CTL (3.6 vs. 4.3, respectively); CO-300 decreased acetate and increased propionate, reducing C2 :C3 (p < 0.001; 2.8 vs. 3.6 for CO-300 and average of other doses, respectively); PE-30 and PE-300 reduced NH3 -N by 14% and increased total VFA by 29% compared with CTL (p < 0.05). Further in vivo investigations may consider L. pacari (LP-30), Copaifera spp. (CO-300) oleoresin and P. emarginatus oleoresin (PE-30 and PE-300) in diets with high inclusion of concentrate.


Assuntos
Fabaceae , Rúmen , Ração Animal/análise , Animais , Dieta/veterinária , Digestão , Ácidos Graxos Voláteis/metabolismo , Fermentação , Extratos Vegetais/farmacologia , Rúmen/metabolismo
8.
Chemistry ; 26(22): 5017-5026, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32027765

RESUMO

The harmful impact caused by pesticides on human health and the environment necessitates the development of efficient degradation processes and control of prohibited stocks of such substances. Organophosphates (OPs) are among the most used agrochemicals in the world and their degradation can proceed through several possible pathways. Investigating the reactivity of OPs with nucleophilic species allows one to propose new and efficient catalyst scaffolds for use in detoxification. In light of the remarkable catalytic activity of imidazole (IMZ) at promoting dephosphorylation processes of OPs, the reactivity of 4(5)-hydroxymethylimidazole (HMZ) with diethyl-2,4-dinitrophenylphosphate (DEDNPP) and Paraoxon are evaluated by combining experimental and theoretical approaches. It is observed that HMZ is an efficient and regiospecific catalyst with reactivity modulated by competing tautomers. To propose an optimal IMZ-based catalyst, quantum chemical calculations were performed for monosubstituted 4(5)IMZ derivatives that might cleave DEDNPP. Both inductive effects and hydrogen bonding by the substituents are shown to influence barriers and mechanisms.

9.
An Acad Bras Cienc ; 92(3): e20190222, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32935736

RESUMO

This study aimed to evaluate the performance in feedlot and temperament of Nellore bulls classified by residual feed intake. The residual feed intake was calculated as the difference between the observed and predicted dry matter intake. Bulls classified as low residual feed intake had lower dry matter intake (kg day-1) and dry matter intake (g kg-1 d-1) of body weight, and were more efficient in feed conversion ratio than those classified as medium and high. The average daily gain didn't differ among residual feed intake classes and was 1.69 kg day-1, 1.82 kg day-1 and 1.71 kg day-1 for bulls classified as low, medium, or high, respectively. The residual feed intake was positively associated with dry matter intake, feed conversion ratio and subcutaneous fat thickness. The subcutaneous fat thickness was lower in bulls classified as low residual feed intake than in those with medium and high. No differences were observed in flight speed and reactivity score among residual feed intake classes. Overall, we concluded that bulls classified as low residual feed intake consumed less dry matter than high, with no differences in average daily gain, temperamentand had better feed efficiency, albeit their subcutaneous fat thickness was lower.


Assuntos
Temperamento , Ração Animal/análise , Animais , Peso Corporal , Bovinos , Dieta , Masculino
10.
BMC Bioinformatics ; 20(Suppl 6): 532, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822264

RESUMO

BACKGROUND: Myocarditis is defined as the inflammation of the myocardium, i.e. the cardiac muscle. Among the reasons that lead to this disease, we may include infections caused by a virus, bacteria, protozoa, fungus, and others. One of the signs of the inflammation is the formation of edema, which may be a consequence of the interaction between interstitial fluid dynamics and immune response. This complex physiological process was mathematically modeled using a nonlinear system of partial differential equations (PDE) based on porous media approach. By combing a model based on Biot's poroelasticity theory with a model for the immune response we developed a new hydro-mechanical model for inflammatory edema. To verify this new computational model, T2 parametric mapping obtained by Magnetic Resonance (MR) imaging was used to identify the region of edema in a patient diagnosed with unspecific myocarditis. RESULTS: A patient-specific geometrical model was created using MRI images from the patient with myocarditis. With this model, edema formation was simulated using the proposed hydro-mechanical mathematical model in a two-dimensional domain. The computer simulations allowed us to correlate spatiotemporal dynamics of representative cells of the immune systems, such as leucocytes and the pathogen, with fluid accumulation and cardiac tissue deformation. CONCLUSIONS: This study demonstrates that the proposed mathematical model is a very promising tool to better understand edema formation in myocarditis. Simulations obtained from a patient-specific model reproduced important aspects related to the formation of cardiac edema, its area, position, and shape, and how these features are related to immune response.


Assuntos
Simulação por Computador , Edema , Imageamento por Ressonância Magnética/métodos , Miocardite , Medicina de Precisão/métodos , Biologia Computacional , Edema/diagnóstico por imagem , Edema/etiologia , Humanos , Interpretação de Imagem Assistida por Computador , Miocardite/complicações , Miocardite/diagnóstico por imagem
11.
Blood ; 128(12): 1555-61, 2016 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-27412888

RESUMO

Cardiovascular disease resulting from iron accumulation is still a major cause of death in patients with thalassemia major (TM). Voltage-gated calcium-channel blockade prevents iron entry into cardiomyocytes and may provide an adjuvant treatment to chelation, reducing myocardial iron uptake. We evaluated whether addition of amlodipine to chelation strategies would reduce myocardial iron overload in TM patients compared with placebo. In a multicenter, double-blind, randomized, placebo-controlled trial, 62 patients were allocated to receive oral amlodipine 5 mg/day or placebo in addition to their current chelation regimen. The main outcome was change in myocardial iron concentration (MIC) determined by magnetic resonance imaging at 12 months, with patients stratified into reduction or prevention groups according to their initial T2* below or above the normal human threshold of 35 ms (MIC, 0.59 mg/g dry weight). At 12 months, patients in the reduction group receiving amlodipine (n = 15) had a significant decrease in MIC compared with patients receiving placebo (n = 15) with a median of -0.26 mg/g (95% confidence interval, -1.02 to -0.01) vs 0.01 mg/g (95% confidence interval, -0.13 to 0.23), P = .02. No significant changes were observed in the prevention group (treatment-effect interaction with P = .005). The same findings were observed in the subgroup of patients with T2* <20 ms. Amlodipine treatment did not cause any serious adverse events. Thus, in TM patients with cardiac siderosis, amlodipine combined with chelation therapy reduced cardiac iron more effectively than chelation therapy alone. Because this conclusion is based on subgroup analyses, it needs to be confirmed in ad hoc clinical trials. This trial was registered at www.clinicaltrials.gov identifier as #NCT01395199.


Assuntos
Anlodipino/uso terapêutico , Terapia por Quelação , Vasodilatadores/uso terapêutico , Talassemia beta/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Criança , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Ferro/metabolismo , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Prognóstico , Adulto Jovem
12.
Acta Radiol ; 58(6): 698-701, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27614069

RESUMO

Background Iron overload assessment with magnetic resonance imaging (MRI) using T2* has become a key diagnostic method in the management of many diseases. Quantitative analysis of the MRI images with a cost-effective tool has been a limitation to increased use of the method. Purpose To provide a free software solution for this purpose comparing the results with a commercial solution. Material and Methods The free tool was developed as a standalone program to be directly downloaded and ran in a common personal computer platform without the need of a dedicated workstation. Liver and cardiac T2* values were calculated using both tools and the values obtained compared between them in a group of 56 patients with suspected iron overload using Bland-Altman plots and concordance correlation coefficients (CCC). Results In the heart, the mean T2* differences between the two methods was 0.46 ms (95% confidence interval [CI], -0.037 -0.965) and in the liver 0.49 ms (95% CI, 0.257-0.722). The CCC for both the heart and the liver were significantly high (0.98 [95% CI, 0.966-0.988] with a Pearson ρ of 0.9811 and 0.991 [95% CI, 0.986-0.994] with a Pearson ρ of 0.996, respectively. No significant differences were observed when analyzing only patients with abnormal concentrations of iron in both organs compared to the whole cohort. Conclusion The proposed free software tool is accurate for calculation of T2* values of the liver and heart and might be a solution for centers that cannot use paid commercial solutions.


Assuntos
Coração/diagnóstico por imagem , Sobrecarga de Ferro/diagnóstico por imagem , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Software , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino
13.
Vet Med Int ; 2024: 5512555, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974507

RESUMO

Foot disorders are responsible for up to 5% of confinement losses. Identifying the cause of lameness and applying the correct treatment are crucial measures. The possibility of determining the probable origins of digital lesions, their extension, and assistance in cases in which it was not possible to reach a definitive clinical diagnosis demonstrates that the radiographic evaluation provides information of great importance on cattle digits. Thus, this study aimed to investigate possible radiographic changes in the hoof, bone structures, and soft tissues of the digits of Nelore bulls at the end of the confinement period. Regarding the main signs, 100% (n = 24) showed proliferation of enthesophytes and osteophytes and irregular contours, 62.5% (n = 15) enlargement of vascular channels, 37.5% (n = 9) osteolysis, 33.4% (n = 8) gas content in the white line region, 20.84% (n = 5) gas content in the dorsal lamina region, and 4.16% (n = 1) presented palisade periosteal reaction. Ten (41.7%) out of 24 (100%) animals evaluated at the end of the confinement presented lameness, three animals of score three, four animals of score two, and three animals of score one. The higher the score indicating the severity of the signs observed in the visual assessment of the radiographs, the higher the internal angle values (moderate correlation of 0.5 and p < 0.05). A higher prevalence of osteo-proliferative radiographic changes was identified at the end of the 114-day confinement period in the third phalanx of Nellore cattle even in animals that had no lameness.

14.
Vet Res Commun ; 48(2): 1003-1013, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38051450

RESUMO

Bovine laminitis disorder results in animal welfare and economic concerns in dairy and beef farms worldwide. However, the affected metabolic pathways, pathophysiologic characteristics, and inflammatory mechanisms remain unclear, hampering the development of new diagnostics. Using cerumen (earwax) as a source of volatile metabolites (cerumenomic) that carry valuable biological information has interesting implications for veterinary medicine. Nonetheless, up to now, no applications of veterinary cerumenomic assays have been made to identify bovine laminitis. This work aims to develop a veterinary cerumenomic assay for bovine laminitis identification that is non-invasive, robust, accurate, and sensitive to detecting the metabolic disturbances in bovine volatile metabolome. Twenty earwax samples (10 from healthy/control calves and 10 from laminitis calves) were collected from Nellore cattle, followed by Headspace/Gas Chromatography-Mass Spectrometry (HS/GC-MS) analysis and biomarker selection in two multivariate approaches: semiquantitative (intensity data) and semiqualitative (binary data). Following the analysis, cerumen volatile metabolites were indicated as candidate biomarkers for identifying bovine laminitis by monitoring their intensity or occurrence. In the semiquantitative strategy, the p-cresol presented the highest diagnostic figures of merit (area under the curve: 0.845, sensitivity: 0.700, and specificity: 0.900). Regarding the binary approach, a panel combining eight variables/volatiles, with formamide being the most prominent one, showed an area under the curve, sensitivity, and specificity of 0.97, 0.81, and 0.90, respectively. In summary, this work describes the first veterinary cerumenomic assay for bovine laminitis that indicates new metabolites altered during the inflammatory condition, paving the way for developing laminitis early diagnosis by monitoring the cerumen metabolites.


Assuntos
Doenças dos Bovinos , Dermatite , Bovinos , Animais , Dermatite/veterinária , Cerume/metabolismo , Doenças dos Bovinos/diagnóstico , Biomarcadores
15.
Cell Immunol ; 281(1): 11-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23416719

RESUMO

Risk factors for atherosclerosis may contribute to chronic low-grade inflammation. A highly cytotoxic and inflammatory CD4(+) cell subset (CD4(+)CD28(null) cells) has been associated with inflammatory diseases, including acute coronary syndromes (ACS). The aim of this study was to quantify and characterize CD4(+)CD28(null) cells in individuals with risk factors for atherosclerosis and patients with coronary artery disease (CAD). In order to achieve this goal, peripheral blood mononuclear cells (PBMCs) from individuals with risk factors for atherosclerosis and patients with CAD were analyzed using flow cytometry to detect cytotoxic molecules and evaluate the expression of homing receptors and inflammatory cytokines in CD4(+) cell subsets. The cells were evaluated ex vivo and after stimulation in culture. We found no differences in the proportions of CD4(+)CD28(null) cells among the groups. Compared with the CD4(+)CD28(+) population, the ex vivo CD4(+)CD28(null) subset from all groups expressed higher levels of granzymes A and B, perforin, granulysin and interferon-γ (IFN-γ). Individuals with risk factors and patients with ACS showed the highest levels of cytotoxic molecules. After stimulation, tumor necrosis factor-α (TNF-α) expression in the CD4(+)CD28(null) subset from these groups increased more than in the other groups. Stimulation with LPS decreased the expression of cytotoxic molecules by CD4(+)CD28(null) cells in all groups. In conclusion, our results show that risk factors for atherosclerosis may alter the CD4(+)CD28(null) cells phenotype, increasing their cytotoxic potential. Our findings also suggest that CD4(+)CD28(null) cells may participate in the early phases of atherosclerosis.


Assuntos
Aterosclerose/imunologia , Antígenos CD28/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Doença da Artéria Coronariana/imunologia , Subpopulações de Linfócitos T/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Diferenciação de Linfócitos T/biossíntese , Linfócitos T CD4-Positivos/imunologia , Feminino , Granzimas/biossíntese , Humanos , Interferon gama/biossíntese , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Perforina/biossíntese , Receptores CCR7/metabolismo , Receptores CXCR3/metabolismo , Fatores de Risco , Subpopulações de Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/farmacologia
16.
J Cardiovasc Magn Reson ; 15: 60, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23870663

RESUMO

The 16th Annual Scientific Sessions of the Society for Cardiovascular Magnetic Resonance (SCMR) took place in San Francisco, USA at the end of January 2013. With a faculty of experts from across the world, this congress provided a wealth of insight into cutting-edge research and technological development. This review article intends to provide a highlight of what represented the most significant advances in the field of cardiovascular magnetic resonance (CMR) during this year's meeting.


Assuntos
Doenças Cardiovasculares/diagnóstico , Imageamento por Ressonância Magnética/métodos , Humanos
17.
J Cardiovasc Magn Reson ; 15: 83, 2013 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-24050721

RESUMO

BACKGROUND: Patients with Sickle cell disease (SCD) who receive regular transfusions are at risk for developing cardiac toxicity from iron overload. The aim of this study was to assess right and left cardiac volumes and function, late gadolinium enhancement (LGE) and iron deposits in patients with SCD using CMR, correlating these values with transfusion burden, ferritin and hemoglobin levels. METHODS: Thirty patients with SCD older than 20 years of age were studied in a 1.5 T scanner and compared to age- and sex-matched normal controls. Patients underwent analysis of biventricular volumes and function, LGE and T2* assessment of the liver and heart. RESULTS: When compared to controls, patients with SCD presented higher left ventricular (LV) volumes with decreased ejection fraction (EF) with an increase in stroke volume (SV) and LV hypertrophy. The right ventricle (RV) also presented with a decreased EF and hypertrophy, with an increased end-systolic volume. Although twenty-six patients had increased liver iron concentrations (median liver iron concentration value was 11.83 ± 9.66 mg/g), only one patient demonstrated an abnormal heart T2* < 20 msec. Only four patients (13%) LGE, with only one patient with an ischemic pattern. CONCLUSIONS: Abnormal heart iron levels and myocardial scars are not a common finding in SCD despite increased liver iron overload. The significantly different ventricular function seen in SCD compared to normal suggests the changes in RV and LV function may not be due to the anemia alone. Future studies are necessary to confirm this association.


Assuntos
Anemia Falciforme/complicações , Hipertrofia Ventricular Esquerda/diagnóstico , Hipertrofia Ventricular Direita/diagnóstico , Fígado/metabolismo , Imageamento por Ressonância Magnética , Miocárdio/patologia , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Direita/diagnóstico , Função Ventricular Esquerda , Função Ventricular Direita , Adulto , Anemia Falciforme/sangue , Estudos de Casos e Controles , Feminino , Ferritinas/sangue , Hemoglobinas/metabolismo , Humanos , Hipertrofia Ventricular Esquerda/sangue , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Hipertrofia Ventricular Direita/sangue , Hipertrofia Ventricular Direita/etiologia , Hipertrofia Ventricular Direita/fisiopatologia , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Valor Preditivo dos Testes , Estudos Prospectivos , Volume Sistólico , Disfunção Ventricular Esquerda/sangue , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Direita/sangue , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia , Adulto Jovem
19.
Transfusion ; 52(10): 2256-68, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22404719

RESUMO

Iron overload is one of the major causes of morbidity and death in patients undergoing chronic transfusion therapy. Furthermore, excessive iron accumulation in the heart may result in impaired left ventricular dysfunction. With accurate monitoring techniques and treatment regimens, progression of heart complications can be followed, and their natural history changed. Iron chelation therapy is the mainstay of prevention and reversal of myocardial iron overload. Despite recent appraisals of general chelating strategies, the management of iron chelation in chronically transfused patients with a focus on the heart has not been extensively assessed. New studies published in the past couple of years have provided important new data in this topic and therefore this review summarizes the major studies that examined the removal of iron from the heart with the iron chelators: deferoxamine, deferiprone, and deferasirox. Since chronically transfused patients and their cardiac clinical presentations vary widely, this review tries to identify--with each drug--the precise scenarios evaluated, linking patients' baseline characteristics, clinical setting, and drug intake and dosing. Ultimately, by stratifying patients according to their cardiac iron overload status and ventricular function, this review identifies possible approaches for the initial treatment and follow-up of transfusion-related cardiac iron overload.


Assuntos
Cardiomiopatia Dilatada/tratamento farmacológico , Terapia por Quelação , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Reação Transfusional , Disfunção Ventricular Esquerda/tratamento farmacológico , Benzoatos/administração & dosagem , Benzoatos/uso terapêutico , Cardiomiopatia Dilatada/etiologia , Cardiomiopatia Dilatada/patologia , Estudos Transversais , Deferasirox , Deferiprona , Desferroxamina/administração & dosagem , Desferroxamina/uso terapêutico , Método Duplo-Cego , Quimioterapia Combinada , Previsões , Humanos , Quelantes de Ferro/administração & dosagem , Sobrecarga de Ferro/etiologia , Imageamento por Ressonância Magnética , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Piridonas/administração & dosagem , Piridonas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Resultado do Tratamento , Triazóis/administração & dosagem , Triazóis/uso terapêutico , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/patologia
20.
Ann Hematol ; 91(12): 1839-44, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22878458

RESUMO

Thalassemia major (TM) patients have altered ventricular volumes and ejection fraction compared to normals, although evidence for these findings stem from restricted patient groups and has never been reproduced. We sought to evaluate cardiac parameters by cardiovascular magnetic resonance (CMR) in a group of young TM patients not covered by previous studies that are more representative of the TM population in many countries. Seventy patients including 40 TM with normal myocardial iron concentrations, and 30 age- and gender-matched normal (NL) volunteers underwent a CMR study for assessment of left and right ventricle volumes and function using a 1.5-T scanner. Left and right ventricle ejection fraction, indexed systolic and diastolic volumes, and indexed mass were compared between the two groups. Mean age of TM patients was 18.2 ± 7.1 versus 17.5 ± 8.5 years in NL with no significant differences (P = 0.73). There was no difference in left ventricular (LV) ejection fraction between the groups (TM 64.9 ± 5.7 %, NL 64.9 ± 5.2 %; P = 0.97). LV normalized end-diastolic and end-systolic volumes were significantly higher in patients with TM compared to NL volunteers (76.8 ± 19.4 versus 66.6 ± 11.7 mL/m², P = 0.008, and 27.0 ± 8.8 versus 23.6 ± 5.0 mL/m², P = 0.045). LV indexed mass was also higher in TM patients compared to NL (51.2 ± 11.9 versus 42.0 ± 8.5 g/m², P < 0.001). No significant differences were observed in right ventricular parameters. In conclusion, younger patients with TM do not present different left or right ventricular function values compared to normal controls despite having increased left ventricular volumes and mass.


Assuntos
Ventrículos do Coração/fisiopatologia , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Direita/fisiopatologia , Talassemia beta/fisiopatologia , Adolescente , Adulto , Brasil , Volume Cardíaco , Criança , Estudos de Coortes , Diagnóstico Precoce , Feminino , Ventrículos do Coração/química , Ventrículos do Coração/patologia , Humanos , Ferro/análise , Imageamento por Ressonância Magnética , Masculino , Miocárdio/química , Miocárdio/patologia , Índice de Gravidade de Doença , Caracteres Sexuais , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Direita/diagnóstico , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/patologia , Adulto Jovem
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