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1.
Artigo em Inglês | MEDLINE | ID: mdl-38780711

RESUMO

PURPOSE: Exercise imaging using current modalities can be challenging. This was patient focused study to establish the feasibility and reproducibility of exercise-cardiovascular magnetic resonance imaging (EX-CMR) acquired during continuous in-scanner exercise in asymptomatic patients with primary mitral regurgitation (MR). METHODS: This was a prospective, feasibility study. Biventricular volumes/function, aortic flow volume, MR volume (MR-Rvol) and regurgitant fraction (MR-RF) were assessed at rest and during low- (Low-EX) and moderate-intensity exercise (Mod-EX) in asymptomatic patients with primary MR. RESULTS: Twenty-five patients completed EX-CMR without complications. Whilst there were no significant changes in the left ventricular (LV) volumes, there was a significant increase in the LVEF (rest 63 ± 5% vs. Mod-EX 68 ± 6%;p = 0.01). There was a significant reduction in the right ventricular (RV) end-systolic volume (rest 68 ml(60-75) vs. Mod-EX 46 ml(39-59);p < 0.001) and a significant increase in the RV ejection fraction (rest 55 ± 5% vs. Mod-EX 65 ± 8%;p < 0.001). Whilst overall, there were no significant group changes in the MR-Rvol and MR-RF, individual responses were variable, with MR-Rvol increasing by ≥ 15 ml in 4(16%) patients and decreasing by ≥ 15 ml in 9(36%) of patients. The intra- and inter-observer reproducibility of LV volumes and aortic flow measurements were excellent, including at Mod-EX. CONCLUSION: EX-CMR is feasible and reproducible in patients with primary MR. During exercise, there is an increase in the LV and RV ejection fraction, reduction in the RV end-systolic volume and a variable response of MR-Rvol and MR-RF. Understanding the individual variability in MR-Rvol and MR-RF during physiological exercise may be clinically important.

2.
Sci Rep ; 14(1): 7752, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565858

RESUMO

Understanding the impact of greenhouse gas (GHG) emissions and carbon stock is crucial for effective climate change assessment and agroecosystem management. However, little is known about the effects of organic amendments on GHG emissions and dynamic changes in carbon stocks in salt-affected soils. We conducted a pot experiment with four treatments including control (only fertilizers addition), biochar, vermicompost, and compost on non-saline and salt-affected soils, with the application on a carbon equivalent basis under wheat crop production. Our results revealed that the addition of vermicompost significantly increased soil organic carbon content by 18% in non-saline soil and 52% in salt-affected soil compared to the control leading to improvements in crop productivity i.e., plant dry biomass production by 57% in non-saline soil with vermicompost, while 56% with the same treatment in salt-affected soil. The grain yield was also noted 44 and 50% more with vermicompost treatment in non-saline and salt-affected soil, respectively. Chlorophyll contents were observed maximum with vermicompost in non-saline (24%), and salt-affected soils (22%) with same treatments. Photosynthetic rate (47% and 53%), stomatal conductance (60% and 12%), and relative water contents (38% and 27%) were also noted maximum with the same treatment in non-saline and salt-affected soils, respectively. However, the highest carbon dioxide emissions were observed in vermicompost- and compost-treated soils, leading to an increase in emissions of 46% in non-saline soil and 74% in salt-affected soil compared to the control. The compost treatment resulted in the highest nitrous oxide emissions, with an increase of 57% in non-saline soil and 62% in salt-affected soil compared to the control. In saline and non-saline soils treated with vermicompost, the global warming potential was recorded as 267% and 81% more than the control, respectively. All treatments, except biochar in non-saline soil, showed increased net GHG emissions due to organic amendment application. However, biochar reduced net emissions by 12% in non-saline soil. The application of organic amendments increased soil organic carbon content and crop yield in both non-saline and salt-affected soils. In conclusion, biochar is most effective among all tested organic amendments at increasing soil organic carbon content in both non-saline and salt-affected soils, which could have potential benefits for soil health and crop production.


Assuntos
Compostagem , Gases de Efeito Estufa , Solo , Agricultura/métodos , Triticum , Carbono , Carvão Vegetal , Cloreto de Sódio , Cloreto de Sódio na Dieta , Óxido Nitroso/análise , Dióxido de Carbono/análise
3.
J Magn Reson Imaging ; 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38344930

RESUMO

BACKGROUND: Four-dimensional-flow cardiac MR (4DF-MR) offers advantages in primary mitral regurgitation. The relationship between 4DF-MR-derived mitral regurgitant volume (MR-Rvol) and the post-operative left ventricular (LV) reverse remodeling has not yet been established. PURPOSE: To ascertain if the 4DF-MR-derived MR-Rvol correlates with the LV reverse remodeling in primary mitral regurgitation. STUDY TYPE: Prospective, single-center, two arm, interventional vs. nonintervention observational study. POPULATION: Forty-four patients (male N = 30; median age 68 [59-75]) with at least moderate primary mitral regurgitation; either awaiting mitral valve surgery (repair [MVr], replacement [MVR]) or undergoing "watchful waiting" (WW). FIELD STRENGTH/SEQUENCE: 5 T/Balanced steady-state free precession (bSSFP) sequence/Phase contrast imaging/Multishot echo-planar imaging pulse sequence (five shots). ASSESSMENT: Patients underwent transthoracic echocardiography (TTE), phase-contrast MR (PMRI), 4DF-MR and 6-minute walk test (6MWT) at baseline, and a follow-up PMRI and 6MWT at 6 months. MR-Rvol was quantified by PMRI, 4DF-MR, and TTE by one observer. The pre-operative MR-Rvol was correlated with the post-operative decrease in the LV end-diastolic volume index (LVEDVi). STATISTICAL TESTS: Included Student t-test/Mann-Whitney test/Fisher's exact test, Bland-Altman plots, linear regression analysis and receiver operating characteristic curves. Statistical significance was defined as P < 0.05. RESULTS: While Bland-Altman plots demonstrated similar bias between all the modalities, the limits of agreement were narrower between 4DF-MR and PMRI (bias 15; limits of agreement -36 mL to 65 mL), than between 4DF-MR and TTE (bias -8; limits of agreement -106 mL to 90 mL) and PMRI and TTE (bias -23; limits of agreement -105 mL to 59 mL). Linear regression analysis demonstrated a significant association between the MR-Rvol and the post-operative decrease in the LVEDVi, when the MR-Rvol was quantified by PMRI and 4DF-MR, but not by TTE (P = 0.73). 4DF-MR demonstrated the best diagnostic performance for reduction in the post-operative LVEDVi with the largest area under the curve (4DF-MR 0.83; vs. PMRI 0.78; and TTE 0.51; P = 0.89). DATA CONCLUSION: This study demonstrates the potential clinical utility of 4DF-MR in the assessment of primary mitral regurgitation. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 5.

4.
Front Plant Sci ; 14: 1221434, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37662164

RESUMO

Environmental quality and food safety is threatened by contamination of lead (Pb) and cadmium (Cd) heavy metals in agricultural soils. Therefore, it is necessary to develop effective techniques for remediation of such soils. In this study, we prepared iron-modified biochar (Fe-BC) which combines the unique characteristics of pristine biochar (BC) and iron. The current study investigated the effect of pristine and iron modified biochar (Fe-BC) on the nutritional values of soil and on the reduction of Pb and Cd toxicity in wheat plants (Triticum aestivum L.). The findings of present study exhibited that 2% Fe-BC treatments significantly increased the dry weights of roots, shoots, husk and grains by 148.2, 53.2, 64.2 and 148%, respectively compared to control plants. The 2% Fe-BC treatment also enhanced photosynthesis rate, transpiration rate, stomatal conductance, intercellular CO2, chlorophyll a and b contents, by 43.2, 88.4, 24.9, 32.5, 21.4, and 26.7%, respectively. Moreover, 2% Fe-BC treatment suppressed the oxidative stress in wheat plants by increasing superoxide dismutase (SOD) and catalase (CAT) by 62.4 and 69.2%, respectively. The results showed that 2% Fe-BC treatment significantly lowered Cd levels in wheat roots, shoots, husk, and grains by 23.7, 44.5, 33.2, and 76.3%. Whereas, Pb concentrations in wheat roots, shoots, husk, and grains decreased by 46.4, 49.4, 53.6, and 68.3%, respectively. Post-harvest soil analysis showed that soil treatment with 2% Fe-BC increased soil urease, CAT and acid phosphatase enzyme activities by 48.4, 74.4 and 117.3%, respectively. Similarly, 2% Fe-BC treatment significantly improved nutrients availability in the soil as the available N, P, K, and Fe contents increased by 22, 25, 7.3, and 13.3%, respectively. Fe-BC is a viable solution for the remediation of hazardous Cd and Pb contaminated soils, and improvement of soil fertility status.

5.
Chemosphere ; 340: 139719, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37549746

RESUMO

Toxic and carcinogenic metal (loid)s, such arsenic (As) and cadmium (Cd), found in contaminated paddy soils pose a serious danger to environmental sustainability. Their geochemical activities are complex, making it difficult to manage their contamination. Rice grown in Cd and As-polluted soils ends up in people's bellies, where it can cause cancer, anemia, and the deadly itai sickness. Solving this issue calls for research into eco-friendly and cost-effective remediation technology to lower rice's As and Cd levels. This research delves deeply into the origins of As and Cd in paddy soils, as well as their mobility, bioavailability, and uptake mechanisms by rice plants. It also examines the current methods and reactors used to lower As and Cd contamination in rice. Iron-modified biochar (Fe-BC) is a promising technology for reducing As and Cd toxicity in rice, improving soil health, and boosting rice's nutritional value. Biochar's physiochemical characteristics are enhanced by the addition of iron, making it a potent adsorbent for As and Cd ions. In conclusion, Fe-BC's biomembrane properties make them an attractive option for remediating As- and Cd-contaminated paddy soils. More efficient mitigation measures, including the use of biomembrane technology, can be developed when sustainable agriculture practices are combined with these technologies.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Humanos , Cádmio/análise , Ferro/química , Arsênio/análise , Solo/química , Oryza/química , Medição de Risco , Poluentes do Solo/análise
6.
BMC Cardiovasc Disord ; 23(1): 246, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170253

RESUMO

OBJECTIVE: To investigate whether left atrial (LA) volume and left ventricular filling pressure (LVFP) assessed by cardiovascular magnetic resonance (CMR) change during adenosine delivered myocardial hyperaemia as part of a first-pass stress perfusion study. METHODS AND RESULTS: We enrolled 33 patients who had stress CMR. These patients had a baseline four-chamber cine and stress four-chamber cine, which was done at peak myocardial hyperaemic state after administering adenosine. The left and right atria were segmented in the end ventricular diastolic and systolic phases. Short-axis cine stack was segmented for ventricular functional assessment. At peak hyperaemic state, left atrial end ventricular systolic volume just before mitral valve opening increased significantly from baseline in all (91 ± 35ml vs. 81 ± 33ml, P = 0.0002), in males only (99 ± 35ml vs. 88 ± 33ml, P = 0.002) and females only (70 ± 26ml vs. 62 ± 22ml, P = 0.02). The right atrial end ventricular systolic volume increased less significantly from baseline (68 ± 21ml vs. 63 ± 20ml, P = 0.0448). CMR-derived LVFP (equivalent to pulmonary capillary wedge pressure) increased significantly at the peak hyperaemic state in all (15.1 ± 2.9mmHg vs. 14.4 ± 2.8mmHg, P = 0.0002), females only (12.9 ± 2.1mmHg vs. 12.3 ± 1.9mmHg, P = 0.029) and males only (15.9 ± 2.8mmHg vs. 15.2 ± 2.7mmHg, P = 0.002) cohorts. CONCLUSION: Left atrial volume assessment by CMR can measure acute and dynamic changes in preloading conditions on the left ventricle. During adenosine administered first-pass perfusion CMR, left atrial volume and LVFP rise significantly.


Assuntos
Fibrilação Atrial , Hiperemia , Masculino , Feminino , Humanos , Átrios do Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética , Perfusão , Volume Sistólico , Imagem Cinética por Ressonância Magnética/métodos , Função Ventricular Esquerda
7.
J Am Coll Radiol ; 18(2): 274-279, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32768425

RESUMO

OBJECTIVE: To assess consistency and long-term progress in thyroid biopsy performed by trained sonographers under supervision of a radiologist. METHODS: Trained sonographers started performing thyroid biopsy at our institute in August 2011. The data for this study were extracted from a prospectively maintained database for ultrasound guided thyroid biopsy and included the number of thyroid fine needle aspiration biopsy procedures performed between August 2011 and 2016 and the final cytopathology report as per the Bethesda Classification. For the analysis, the study was divided into two time periods: initial postimplementation period (August 2011 to 2013) and late postimplementation period (2014-2016). RESULTS: In all, 5,538 thyroid biopsies were performed by trained sonographers in the period, 2,561 in the initial implementation period and 2,977 between 2014 and 2016. The unsatisfactory rates dropped from 21% to 10% in the two periods (P < .001), and the proportion of malignant nodules on cytopathology increased from 6% to 7% in the two periods (P = .010). Wait times for thyroid biopsies remained low during the period. CONCLUSION: Sonographers trained to perform ultrasound guided thyroid biopsies provide persistent improved patient care over a long-term period. This reinforces the role of physician extenders in targeted scopes of practice.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Biópsia por Agulha Fina , Humanos , Estudos Retrospectivos , Especialização , Ultrassonografia
8.
Int J Phytoremediation ; 19(2): 199-206, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27419530

RESUMO

The present study aimed to evaluate the effect of soil-applied Zn and Cu on absorption and accumulation of Cd applied through irrigation water in legume (chickpea and mung bean) and cereal (wheat and maize) crops. The results revealed that Cd in irrigation water at higher levels (2 and 5 mg L-1) significantly (p < 0.05) reduced the plant biomass while the soil application of Zn and Cu, singly or combined, favored the biomass production. Plant tissue Cd concentration increased linearly with the increasing application of Cd via irrigation water. While Cd application caused a redistribution of metals in grains, straw, and roots with the highest concentration of Cd, Zn, and Cu occurred in roots followed by straw and grains. Zinc addition to soil alleviated Cd toxicity by decreasing Cd concentration in plant tissues due to a possible antagonistic effect. The addition of Cu to the soil had no consistent effects on Zn and Cd contents across all crops. Inhibitory effects of Cd on the uptake and accumulation of Zn and Cu have also been observed at higher Cd load. Thus, soil-applied Zn and Cu antagonized Cd helping the plant to cope with its toxicity and suppressed the toxic effects of Cd in plant tissues, thus favoring plant growth.


Assuntos
Cádmio/metabolismo , Cobre/química , Fabaceae/metabolismo , Poaceae/metabolismo , Poluentes do Solo/metabolismo , Zinco/química , Biodegradação Ambiental , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/metabolismo , Fabaceae/efeitos dos fármacos , Poaceae/efeitos dos fármacos
9.
Radiology ; 276(3): 894-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25897472

RESUMO

PURPOSE: To develop and implement a program where selected sonographers would be trained to perform thyroid biopsies independently under the supervision of a radiologist, with the goal of improving efficiency and quality. MATERIALS AND METHODS: Institutional research ethics board approval was obtained for this retrospective study, with waiver of informed consent. After approval from the relevant regulatory bodies, four sonographers successfully completed a training program and began to perform all thyroid biopsies (with informed consent) in a room adjacent to the main radiologist-run biopsy room, where the radiologist was available for backup as needed. In the preimplementation period (January 2010 to April 2011), 1321 nodules were biopsied, 29 of which included on-site cytopathology assessment. In the postimplementation period (August 2011 to July 2012), 1347 nodules were biopsied, 103 of which underwent on-site cytopathology assessment. Wait times and adequacy rates were calculated for both periods. RESULTS: Patient wait times decreased from a mean of 80-90 days before implementation of the thyroid biopsy specialist program to 20-30 days afterward. The percentage of adequate samples improved from 74.6% (985 of 1321 nodules) to 78.6% (1059 of 1347 nodules), with a P value of .015 (74.1% [957 of 1292 nodules] to 77.5% [964 of 1244 nodules] when excluding nodules with on-site cytopathology assessment, P = .0497). The percentage of malignant samples showed no significant change in the two time periods, 5.1% (68 of 1321 nodules) before implementation of the program versus 5.4% (73 of 1347 nodules) after implementation, P = .823 (5.1% [66 of 1292 nodules] vs 5.3% [66 of 1244 nodules] in the respective time periods when excluding nodules with on-site cytopathology assessment, P = .888). No major procedural complications occurred. CONCLUSION: Sonographers can be successfully trained to perform ultrasonography-guided thyroid biopsies safely under the supervision of a radiologist, which can improve wait times and adequacy rates.


Assuntos
Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/patologia , Humanos , Biópsia Guiada por Imagem , Melhoria de Qualidade , Estudos Retrospectivos , Especialização , Fatores de Tempo , Ultrassonografia de Intervenção/normas
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