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1.
Curr Cardiol Rep ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713361

RESUMO

PURPOSE OF REVIEW: The world is proliferating rapidly, with science and technology advancing at an incredible rate. These advances have, however, ushered in an age with a rise in social isolation (SI) and loneliness. SI is an objective term that refers to lacking social contact or support. On the other hand, loneliness is subjective and refers to feeling alone or isolated. These concepts are rapidly gaining prominence mainly due to their negative impact on the physical and psychological health of the population, mainly through behavioural modifications that encompass substance abuse, decreased physical activity and unhealthy food habits, and poor sleep hygiene. This review summarizes the pathophysiology, evaluates the evidence behind impact of SI on cardiovascular mortality, and interventions to overcome SI. RECENT FINDINGS: Through proposed mechanisms, such as activation of the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis, both SI and loneliness have strong evidence linking them to cardiovascular morbidity and mortality. A systematic review and meta-analysis of 90 prospective cohort studies including 2,205,199 individuals reported that SI was independent predictor of cardiovascular mortality with a point estimate of 1.34 (95% confidence interval:1.25-1.44). The evidence so far is compelling and necessitates urgent action with the implementation of strict policies to tackle this issue. As healthcare professionals, it becomes even more critical to remain vigilant, recognize this insidious pandemic, and take appropriate action.

2.
Int J Mol Sci ; 22(17)2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34502258

RESUMO

Magnetopriming has emerged as a promising seed-priming method, improving seed vigor, plant performance and productivity under both normal and stressed conditions. Various recent reports have demonstrated that improved photosynthesis can lead to higher biomass accumulation and overall crop yield. The major focus of the present review is magnetopriming-based, improved growth parameters, which ultimately favor increased photosynthetic performance. The plants originating from magnetoprimed seeds showed increased plant height, leaf area, fresh weight, thick midrib and minor veins. Similarly, chlorophyll and carotenoid contents, efficiency of PSII, quantum yield of electron transport, stomatal conductance, and activities of carbonic anhydrase (CA), Rubisco and PEP-carboxylase enzymes are enhanced with magnetopriming of the seeds. In addition, a higher fluorescence yield at the J-I-P phase in polyphasic chlorophyll a fluorescence (OJIP) transient curves was observed in plants originating from magnetoprimed seeds. Here, we have presented an overview of available studies supporting the magnetopriming-based improvement of various parameters determining the photosynthetic performance of crop plants, which consequently increases crop yield. Additionally, we suggest the need for more in-depth molecular analysis in the future to shed light upon hidden regulatory mechanisms involved in magnetopriming-based, improved photosynthetic performance.


Assuntos
Campos Magnéticos , Fotossíntese , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Clorofila/química , Clorofila/metabolismo , Fluorescência , Folhas de Planta/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/metabolismo
3.
Catheter Cardiovasc Interv ; 90(4): 680-689, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28185394

RESUMO

BACKGROUND: Percutaneous paravalvular leak (PVL) closure is an alternative treatment option for severely symptomatic, high-surgical risk patients with PVL. Some patients require multiple percutaneous PVL closure procedures. However, the procedural characteristics and success rate of re-do PVL closure have not been well studied. AIMS: The aim of this study is to investigate the indications, procedural characteristics, technical success rate, and 30-day major adverse cardiovascular events (MACE) in patients who underwent re-do PVL closure. METHODS: Consecutive patients who underwent percutaneous paramitral or paraaortic leak closure at Mayo Clinic, Rochester, Minnesota from 2004 through 2015 were studied. Clinical and procedural characteristics of patients who underwent re-do PVL closure were compared to age- and sex-matched patients who underwent their first percutaneous PVL closure. Procedure success and 30-day MACE were compared in both the groups. RESULTS: Among 223 identified percutaneous PVL closures, 16 (7%) were re-do procedures. Patients who underwent re-do PVL closure were predominantly men (87.5%) with a mean age of 68 ± 15 years and an estimated mean Society of Thoracic Surgery (STS) 30-day mortality of 4.6 ± 2.8. Half of the re-do PVL closures were performed on mechanical valves and 62.5% were performed on paramitral defects. Indications for re-do PVL closure were: (1) emergence of new significant paravalvular defects in 50%, (2) incomplete index defect closure in 43.75%, and (3) index procedural complication in 6.25% of the cases. Procedural success was 75% in re-do procedures vs. 85.4% in age- and sex-matched control group (P = 0.45). Thirty-day MACE was 12.5% in the re-do group compared to 4.2% in the age- and-sex matched patients who underwent PVL closure for the first time (P = 0.35). CONCLUSION: Re-do percutaneous PVL closure is feasible with favorable procedural success rate and low 30-day MACE. Development of new paravalvular defects is the most common indication for re-do PVL closure, highlighting the importance of careful longitudinal monitoring and follow-up. © 2017 Wiley Periodicals, Inc.


Assuntos
Insuficiência da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Insuficiência da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/etiologia , Insuficiência da Valva Aórtica/fisiopatologia , Bioprótese , Estudos de Casos e Controles , Ecocardiografia Doppler em Cores , Ecocardiografia Tridimensional , Ecocardiografia Transesofagiana , Feminino , Próteses Valvulares Cardíacas , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/instrumentação , Hospitais com Alto Volume de Atendimentos , Humanos , Masculino , Pessoa de Meia-Idade , Minnesota , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/fisiopatologia , Sistema de Registros , Reoperação , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/instrumentação , Resultado do Tratamento
5.
Heart Fail Clin ; 11(2): 243-59, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25834973

RESUMO

Percutaneous treatment of mitral regurgitation (MR) is a promising alternative for patients with functional MR (FMR) who are not appropriate for surgery and are not responding to optimal medical therapy and cardiac resynchronization therapy. Unlike degenerative MR, where repair therapy is clearly preferred, the optimal approach for FMR has not been defined. Challenges for novel mitral repair devices are to demonstrate safety and superior efficacy to medical management in higher risk patients. Transcatheter mitral valve replacement is emerging as a feasible therapy, but requires significant additional clinical trials to define its place in treating heart failure related to MR.


Assuntos
Cateterismo Cardíaco/métodos , Insuficiência Cardíaca , Implante de Prótese de Valva Cardíaca/métodos , Insuficiência da Valva Mitral , Valva Mitral , Terapia de Ressincronização Cardíaca/métodos , Fármacos Cardiovasculares/farmacologia , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/fisiopatologia , Humanos , Valva Mitral/fisiopatologia , Valva Mitral/cirurgia , Anuloplastia da Valva Mitral/métodos , Insuficiência da Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/terapia , Seleção de Pacientes , Risco Ajustado
6.
Catheter Cardiovasc Interv ; 84(1): 129-36, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24323764

RESUMO

BACKGROUND: The MitraClip® system is a newer percutaneous device that has shown promising results but data on its safety and efficacy in low- and high-surgical risk populations continues to evolve. We performed a systematic review of the published studies reporting the safety and efficacy of MitraClip® implantation for treatment of moderate to severe and severe mitral regurgitation (MR). METHODS: Reviewers independently searched for relevant articles in Medline and abstracted clinical information based on pre-defined criteria and end-points. Patients were classified as low- or high-surgical risk for conventional mitral valve (MV) surgery based on Society of Thoracic Surgeons score, EuroSCORE, or surgeon discretion. Primary safety outcome was 30-day mortality and primary efficacy outcomes were freedom from death, ≥3+ MR, and requirement for MV surgery during follow-up. RESULTS: Immediate and long-term outcomes of 16 studies, including 2980 patients (age 73.7 ± 0.6 years; 63.3% males) receiving the MitraClip®, were analyzed. Acute procedural success rate was 91.4% with a procedural mortality of 0.1%. Mortality at 30 days and long-term (310 days) follow-up was 4.2 and 15.8%, respectively and was significantly higher in the high-risk group (P = 0.003 and 0.019, respectively). Incidence of major procedural adverse outcomes was relatively low with blood transfusion accounting for most events. At follow-up, the number of patients with ≥3+ MR reduced from 96.3% to 14.7% (P < 0.001), and those with NYHA class III/IV reduced from 83.2% to 23.4% (P < 0.001). CONCLUSION: MitraClip® implantation for moderate to severe or severe MR appears to be safe with a very low procedural mortality. There is significant improvement in functional outcomes although long-term mortality is high, especially in high surgical risk patients.


Assuntos
Cateterismo Cardíaco/métodos , Próteses Valvulares Cardíacas , Insuficiência da Valva Mitral/cirurgia , Humanos , Insuficiência da Valva Mitral/diagnóstico , Desenho de Prótese , Índice de Gravidade de Doença
7.
Plant Physiol Biochem ; 209: 108538, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38520964

RESUMO

Silver nanoparticles (AgNPs) have gained significant attention in various fields due to their unique properties, but their release into the environment has raised concerns about their environmental and biological impacts. Silver nanoparticles can enter plants following their exposure to roots or via stomata following foliar exposure. Upon penetrating the plant cells, AgNPs interact with cellular components and alter physiological and biochemical processes. One of the key concerns associated with plant exposure to AgNPs is the potential of these materials to induce oxidative stress. Silver nanoparticles can also suppress plant growth and development by disrupting essential plant physiological processes, such as photosynthesis, nutrient uptake, water transport, and hormonal regulation. In crop plants, these disruptions may, in turn, affect the productivity and quality of the harvested components and therefore represent a potential threat to agricultural productivity and ecosystem stability. Understanding the phytotoxic effects of AgNPs is crucial for assessing their environmental implications and guiding the development of safe nanomaterials. By delving into the phytotoxic effects of AgNPs, this review contributes to the existing knowledge regarding their environmental risks and promotes the advancement of sustainable nanotechnological practices.


Assuntos
Nanopartículas Metálicas , Prata , Prata/farmacologia , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Ecossistema , Estresse Oxidativo , Plantas
8.
Plant Physiol Biochem ; 206: 108211, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029618

RESUMO

Metals constitute vital elements for plant metabolism and survival, acting as essential co-factors in cellular processes which are indispensable for plant growth and survival. Excess or deficient provision of metal/metalloids puts plant's life and survival at risk, thus considered a potent stress for plants. Chloroplasts as an organelle with a high metal demand form a pivotal site within the metal homeostasis network. Therefore, the metal-mediated electron transport chain (ETC) in chloroplasts is a primary target site of metal/metalloid-induced stresses. Both excess and deficient availability of metal/metalloids threatens plant's photosynthesis in several ways. Energy demands from the photosynthetic carbon reactions should be in balance with energy output of ETC. Malfunctioning of ETC components as a result of metal/metalloid stress initiates photoinhiition. A feedback inhibition from carbon fixation process also impedes the ETC. Metal stress impairs antioxidant enzyme activity, pigment biosynthesis, and stomatal function. However, genetic manipulations, nutrient management, keeping photostasis, and application of phytohormones are among strategies for coping with metal stress. Consequently, a comprehensive understanding of the underlying mechanisms of metal/metalloid stress, as well as the exploration of potential strategies to mitigate its impact on plants are imperative. This review offers a mechanistic insight into the disruption of photosynthesis regulation by metal/metalloids and highlights adaptive approaches to ameliorate their effects on plants. Focus was made on photostasis, nutrient interactions, phytohormones, and genetic interventions for mitigating metal/metalloid stresses.


Assuntos
Metaloides , Reguladores de Crescimento de Plantas/metabolismo , Metais/metabolismo , Fotossíntese , Plantas/genética
9.
JACC Case Rep ; 29(9): 102310, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38576772

RESUMO

We report a successful percutaneous mitral balloon commissurotomy via left transhepatic venous access in a 42-year-old female patient with dextrocardia, situs inversus totalis, and inferior vena cava interruption. fWe also discuss the revisions required for optimal trans-septal approach from the left transhepatic vein.

10.
Am J Physiol Heart Circ Physiol ; 304(6): H861-73, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23335793

RESUMO

Clinical metabolic syndrome conveys a poor prognosis in patients with acute coronary syndrome, not fully accounted for by the extent of coronary atherosclerosis. To explain this observation, we determined whether postischemic myocardial contractile and metabolic function are impaired in a porcine dietary model of metabolic syndrome without atherosclerosis. Micropigs (n = 28) were assigned to a control diet (low fat, no added sugars) or an intervention diet (high saturated fat and simple sugars, no added cholesterol) for 7 mo. The intervention diet produced obesity, hypertension, dyslipidemia, and impaired glucose tolerance, but not atherosclerosis. Under open-chest, anesthetized conditions, pigs underwent 45 min of low-flow myocardial ischemia and 120 min of reperfusion. In both diet groups, contractile function was similar at baseline and declined similarly during ischemia. However, after 120 min of reperfusion, regional work recovered to 21 ± 12% of baseline in metabolic syndrome pigs compared with 61 ± 13% in control pigs (P = 0.01). Ischemia-reperfusion caused a progressive decline in mechanical/metabolic efficiency (regional work/O2 consumption) in metabolic syndrome hearts, but not in control hearts. Metabolic syndrome hearts demonstrated altered fatty acyl composition of cardiolipin and increased Akt phosphorylation in both ischemic and nonischemic regions, suggesting tonic activation. Metabolic syndrome hearts used more fatty acid than control hearts (P = 0.03). When fatty acid availability was restricted by prior insulin exposure, differences between groups in postischemic contractile recovery and mechanical/metabolic efficiency were eliminated. In conclusion, pigs with characteristics of metabolic syndrome demonstrate impaired contractile and metabolic recovery after low-flow myocardial ischemia. Contributory mechanisms may include remodeling of cardiolipin, abnormal activation of Akt, and excessive utilization of fatty acid substrates.


Assuntos
Síndrome Metabólica/fisiopatologia , Contração Miocárdica , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Acil Coenzima A/metabolismo , Animais , Glicemia , Cardiolipinas/metabolismo , Colesterol/metabolismo , Dieta , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/metabolismo , Modelos Animais de Doenças , Glucose/metabolismo , Testes de Função Cardíaca , Insulina/sangue , Sistema de Sinalização das MAP Quinases , Síndrome Metabólica/etiologia , Síndrome Metabólica/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Suínos , Porco Miniatura
11.
Sci Rep ; 13(1): 16675, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794238

RESUMO

CsPbI3 perovskite quantum dots (CPQDs) have received great attention due to their potential in large-scale applications. Increasing the efficiency of CPQDs solar cells is an important issue that is addressed in this paper. Here, we have simulated a 14.61% colloidal CPQD solar cell with the least fitting parameter that shows the accuracy of the following results. The absorber layer properties are varied and different power conversion efficiency (PCE) is achieved for the new device. The results show that colloidal CsPbI3 material properties have a significant effect on the PCE of the device. Finally, the optimized parameters for the absorber layer are listed and the optimum efficiency of 29.88% was achieved for this case. Our results are interesting that help the researchers to work on CsPbI3 materials for the achievement of highly efficient, stable, large-scale, and flexible CPQDs solar cells.

12.
Front Plant Sci ; 14: 1149832, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063220

RESUMO

Overseeded perennial ryegrass (Lolium perenne L.) turf on dormant bermudagrass (Cynodon dactylon Pers. L) in transitional climatic zones (TCZ) experience a severe reduction in its growth due to cold stress. Primary plant nutrients play an important role in the cold stress tolerance of plants. To better understand the cold stress tolerance of overseeded perennial ryegrass under TCZ, a three-factor and five-level central composite rotatable design (CCRD) with a regression model was used to study the interactive effects of nitrogen (N), phosphorus (P), and potassium (K) fertilization on lipid peroxidation, electrolyte leakage, reactive oxygen species (ROS) production, and their detoxification by the photosynthetic pigments, enzymatic and non-enzymatic antioxidants. The study demonstrated substantial effects of N, P, and K fertilization on ROS production and their detoxification through enzymatic and non-enzymatic pathways in overseeded perennial ryegrass under cold stress. Our results demonstrated that the cold stress significantly enhanced malondialdehyde, electrolyte leakage, and hydrogen peroxide contents, while simultaneously decreasing ROS-scavenging enzymes, antioxidants, and photosynthetic pigments in overseeded perennial ryegrass. However, N, P, and K application mitigated cold stress-provoked adversities by enhancing soluble protein, superoxide dismutase, peroxide dismutase, catalase, and proline contents as compared to the control conditions. Moreover, N, P, and, K application enhanced chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids in overseeded perennial ryegrass under cold stress as compared to the control treatments. Collectively, this 2-years study indicated that N, P, and K fertilization mitigated cold stress by activating enzymatic and non-enzymatic antioxidants defense systems, thereby concluding that efficient nutrient management is the key to enhanced cold stress tolerance of overseeded perennial ryegrass in a transitional climate. These findings revealed that turfgrass management will not only rely on breeding new varieties but also on the development of nutrient management strategies for coping cold stress.

13.
Int J Cardiol ; 370: 356-365, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36343795

RESUMO

AIMS: Wall shear stress (WSS) is involved in coronary artery plaque pathological mechanisms and modulation of gene expression. This study aims to provide a comprehensive haemodynamic and biological description of unstable (intact-fibrous-cap, IFC, and ruptured-fibrous-cap, RFC) and stable (chronic coronary syndrome, CCS) plaques and investigate any correlation between WSS and molecular pathways. METHODS AND RESULTS: We enrolled 24 CCS and 25 Non-ST Elevation Myocardial Infarction-ACS patients with IFC (n = 11) and RFC (n = 14) culprit lesions according to optical coherence tomography analysis. A real-time PCR primer array was performed on peripheral blood mononuclear cells for 17 different molecules whose expression is linked to WSS. Computational fluid dynamics simulations were performed in high-fidelity 3D-coronary artery anatomical models for three patients per group. A total of nine genes were significantly overexpressed in the unstable patients as compared to CCS patients, with no differences between IFC and RFC groups (GPX1, MMP1, MMP9, NOS3, PLA2G7, PI16, SOD1, TIMP1, and TFRC) while four displayed different levels between IFC and RFC groups (TNFα, ADAMTS13, EDN1, and LGALS8). A significantly higher WSS was observed in the RFC group (p < 0.001) compared to the two other groups. A significant correlation was observed between TNFα (p < 0.001), EDN1 (p = 0.036), and MMP9 (p = 0.005) and WSS values in the RFC group. CONCLUSIONS: Our data demonstrate that IFC and RFC plaques are subject to different WSS conditions and gene expressions, suggesting that WSS profiling may play an essential role in the plaque instability characterization with relevant diagnostic and therapeutic implications in the era of precision medicine.


Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Ruptura Cardíaca , Placa Aterosclerótica , Humanos , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/genética , Vasos Coronários/patologia , Leucócitos Mononucleares , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/genética , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/genética , Tomografia de Coerência Óptica/métodos , Ruptura Espontânea/metabolismo , Ruptura Espontânea/patologia , Angiografia Coronária/métodos , Galectinas/metabolismo
14.
Cardiovasc Drugs Ther ; 26(3): 195-204, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22450779

RESUMO

PURPOSE: Despite favorable metabolic and vascular effects, thiazolidinedione (TZD) drugs have not convincingly reduced cardiovascular mortality in clinical trials, raising the possibility of countervailing, off-target effects. We previously showed that TZDs block cardiac ATP-sensitive potassium (K(ATP)) channels in pigs. In this study, we investigated whether TZDs affect onset, spectral characteristics, and mortality of ischemic ventricular fibrillation (VF) and whether such effects are recapitulated by a non-selective K(ATP) blocker (glyburide) or a mitochondrial K(ATP) blocker (5-hydroxydecanoate). METHODS: A total of 121 anesthetized pigs were pre-treated with TZD (pioglitazone or rosiglitazone, 1 mg/kg IV, resulting in clinically relevant plasma concentrations), glyburide (1 mg/kg IV), 5-hydroxydecanoate (5 mg/kg IV) or inert vehicle. Ischemia was produced by occlusion of the left anterior descending coronary artery. In a subset of pigs treated with rosiglitazone or vehicle, ischemic preconditioning was performed. RESULTS: VF developed in all but 6 pigs. In non-preconditioned pigs, onset of VF occurred sooner with pioglitazone (11±3 min, p<0.05) or rosiglitazone (14±3 min, p=0.06) than with vehicle (20±2 min). Defibrillation of VF was successful in 44% of pigs treated with vehicle, compared with 0% with pioglitazone (p=0.057) and 33% with rosiglitazone (NS). After ischemic preconditioning, defibrillation was successful in 62% of pigs treated with vehicle, compared with 26% treated with rosiglitazone (p=0.03). TZDs attenuated slowing of conduction due to ischemia and shifted ECG power spectra during VF toward higher frequencies. All effects of TZDs were recapitulated by glyburide, but not by 5-hydroxydecanoate, supporting an interaction of TZDs with the sarcolemmal K(ATP) channel. CONCLUSION: In a porcine model, TZDs promote onset and increase mortality of ischemic VF, associated with alterations of conduction and VF spectral characteristics. Similar effects in a clinical setting might adversely impact cardiovascular mortality.


Assuntos
Hipoglicemiantes/efeitos adversos , Isquemia/fisiopatologia , Tiazolidinedionas/efeitos adversos , Fibrilação Ventricular/fisiopatologia , Animais , Antiarrítmicos/farmacologia , Vasos Coronários/fisiopatologia , Morte Súbita Cardíaca/etiologia , Ácidos Decanoicos/farmacologia , Feminino , Glibureto/farmacologia , Hidroxiácidos/farmacologia , Precondicionamento Isquêmico Miocárdico , Masculino , Pioglitazona , Bloqueadores dos Canais de Potássio/farmacologia , Rosiglitazona , Suínos
15.
Heart Fail Clin ; 8(2): 237-45, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22405663

RESUMO

ß-blockers are an important treatment of heart failure (HF) and are useful in reducing the progression of the syndrome. They should be considered for patients with asymptomatic left ventricular (LV) dysfunction. Evidence-based ß-blocker therapy (bisoprolol, carvedilol, or metoprolol succinate) in combination with standard therapy is a mainstay of treatment of all symptomatic patients with LV systolic dysfunction. Patients in stage B also benefit from the early introduction of ß-blockers, but there are no large randomized clinical trials to support this strategy. Whether there is a role for ivabradine in the treatment of HF is not clear.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Antagonistas Adrenérgicos beta/farmacologia , Animais , Benzazepinas/farmacologia , Benzazepinas/uso terapêutico , Bisoprolol/farmacologia , Bisoprolol/uso terapêutico , Carbazóis/farmacologia , Carbazóis/uso terapêutico , Sistema Cardiovascular/fisiopatologia , Carvedilol , Progressão da Doença , Ventrículos do Coração/efeitos dos fármacos , Humanos , Ivabradina , Propanolaminas/farmacologia , Propanolaminas/uso terapêutico , Sistema Nervoso Simpático/fisiopatologia , Disfunção Ventricular Esquerda/fisiopatologia
16.
Plant Physiol Biochem ; 172: 56-69, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35032888

RESUMO

Potassium (K) is an essential element for the growth and development of plants; however, its scarcity or excessive level leads to distortion of numerous functions in plants. It takes part in the control of various significant functions in plant advancement. Because of the importance index, K is regarded second after nitrogen for whole plant growth. Approximately, higher than 60 enzymes are reliant on K for activation within the plant system, in which K plays a vital function as a regulator. Potassium provides assistance in plants against abiotic stress conditions in the environment. With this background, the present paper reviews the physiological functions of K in plants like stomatal regulation, photosynthesis and water uptake. The article also focuses upon the uptake and transport mechanisms of K along with its role in detoxification of reactive oxygen species and in conferring tolerance to plants against abiotic stresses. It also highlights the research progress made in the direction of K mediated signaling cascades.


Assuntos
Plantas , Potássio , Regulação da Expressão Gênica de Plantas , Desenvolvimento Vegetal , Plantas/metabolismo , Potássio/metabolismo , Transdução de Sinais , Estresse Fisiológico
17.
Plants (Basel) ; 11(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36432887

RESUMO

Flavonoids are characterized as the low molecular weight polyphenolic compounds universally distributed in planta. They are a chemically varied group of secondary metabolites with a broad range of biological activity. The increasing amount of evidence has demonstrated the various physiological functions of flavonoids in stress response. In this paper, we provide a brief introduction to flavonoids' biochemistry and biosynthesis. Then, we review the recent findings on the alternation of flavonoid content under different stress conditions to come up with an overall picture of the mechanism of involvement of flavonoids in plants' response to various abiotic stresses. The participation of flavonoids in antioxidant systems, flavonoid-mediated response to different abiotic stresses, the involvement of flavonoids in stress signaling networks, and the physiological response of plants under stress conditions are discussed in this review. Moreover, molecular and genetic approaches to tailoring flavonoid biosynthesis and regulation under abiotic stress are addressed in this review.

18.
Plants (Basel) ; 11(3)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35161297

RESUMO

In agriculture, abiotic stress is one of the critical issues impacting the crop productivity and yield. Such stress factors lead to the generation of reactive oxygen species, membrane damage, and other plant metabolic activities. To neutralize the harmful effects of abiotic stress, several strategies have been employed that include the utilization of nanomaterials. Nanomaterials are now gaining attention worldwide to protect plant growth against abiotic stresses such as drought, salinity, heavy metals, extreme temperatures, flooding, etc. However, their behavior is significantly impacted by the dose in which they are being used in agriculture. Furthermore, the action of nanomaterials in plants under various stresses still require understanding. Hence, with this background, the present review envisages to highlight beneficial role of nanomaterials in plants, their mode of action, and their mechanism in overcoming various abiotic stresses. It also emphasizes upon antioxidant activities of different nanomaterials and their dose-dependent variability in plants' growth under stress. Nevertheless, limitations of using nanomaterials in agriculture are also presented in this review.

19.
Circ Heart Fail ; 15(1): e009101, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34963308

RESUMO

Right ventricular pressure-volume (PV) analysis characterizes ventricular systolic and diastolic properties independent of loading conditions like volume status and afterload. While long-considered the gold-standard method for quantifying myocardial chamber performance, it was traditionally only performed in highly specialized research settings. With recent advances in catheter technology and more sophisticated approaches to analyze PV data, it is now more commonly used in a variety of clinical and research settings. Herein, we review the basic techniques for PV loop measurement, analysis, and interpretation with the aim of providing readers with a deeper understanding of the strengths and limitations of PV analysis. In the second half of the review, we detail key scenarios in which right ventricular PV analysis has influenced our understanding of clinically relevant topics and where the technique can be applied to resolve additional areas of uncertainty. All told, PV analysis has an important role in advancing our understanding of right ventricular physiology and its contribution to cardiovascular function in health and disease.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Volume Sistólico/fisiologia , Função Ventricular Direita/fisiologia , Pressão Ventricular/fisiologia , Ventrículos do Coração/fisiopatologia , Hemodinâmica/fisiologia , Humanos , Disfunção Ventricular Direita/fisiopatologia , Função Ventricular Esquerda/fisiologia
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