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1.
BMC Plant Biol ; 24(1): 550, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38872083

RESUMO

BACKGROUND: Boron (B) is a micronutrient, but excessive levels can cause phytotoxicity, impaired growth, and reduced photosynthesis. B toxicity arises from over-fertilization, high soil B levels, or irrigation with B-rich water. Conversely, silicon (Si) is recognized as an element that mitigates stress and alleviates the toxic effects of certain nutrients. In this study, to evaluate the effect of different concentrations of Si on maize under boron stress conditions, a factorial experiment based on a randomized complete block design was conducted with three replications in a hydroponic system. The experiment utilized a nutrient solution for maize var. Merit that contained three different boron (B) concentrations (0.5, 2, and 4 mg L-1) and three Si concentrations (0, 28, and 56 mg L-1). RESULTS: Our findings unveiled that exogenous application of B resulted in a substantial escalation of B concentration in maize leaves. Furthermore, B exposure elicited a significant diminution in fresh and dry plant biomass, chlorophyll index, chlorophyll a (Chl a), chlorophyll b (Chl b), carotenoids, and membrane stability index (MSI). As the B concentration augmented, malondialdehyde (MDA) content and catalase (CAT) enzyme activity exhibited a concomitant increment. Conversely, the supplementation of Si facilitated an amelioration in plant fresh and dry weight, total carbohydrate, and total soluble protein. Moreover, the elevated activity of antioxidant enzymes culminated in a decrement in hydrogen peroxide (H2O2) and MDA content. In addition, the combined influence of Si and B had a statistically significant impact on the leaf chlorophyll index, total chlorophyll (a + b) content, Si and B accumulation levels, as well as the enzymatic activities of guaiacol peroxidase (GPX), ascorbate peroxidase (APX), and H2O2 levels. These unique findings indicated the detrimental impact of B toxicity on various physiological and biochemical attributes of maize, while highlighting the potential of Si supplementation in mitigating the deleterious effects through modulation of antioxidant machinery and biomolecule synthesis. CONCLUSIONS: This study highlights the potential of Si supplementation in alleviating the deleterious effects of B toxicity in maize. Increased Si consumption mitigated chlorophyll degradation under B toxicity, but it also caused a significant reduction in the concentrations of essential micronutrients iron (Fe), copper (Cu), and zinc (Zn). While Si supplementation shows promise in counteracting B toxicity, the observed decrease in Fe, Cu, and Zn concentrations warrants further investigation to optimize this approach and maintain overall plant nutritional status.


Assuntos
Boro , Clorofila , Hidroponia , Silício , Zea mays , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento , Zea mays/fisiologia , Zea mays/metabolismo , Boro/toxicidade , Boro/metabolismo , Silício/farmacologia , Clorofila/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Malondialdeído/metabolismo , Carotenoides/metabolismo , Antioxidantes/metabolismo , Catalase/metabolismo
2.
BMC Plant Biol ; 24(1): 648, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38977994

RESUMO

BACKGROUND: A study on photosynthetic and enzyme activity changes and mineral content in lettuce under cadmium stress has been conducted in a greenhouse, utilizing the modulated effect of zinc (Zn) application in the nutrient solution on lettuce. Zn is a micronutrient that plays an essential role in various critical plant processes. Accordingly, three concentrations of Zn (0.022, 5, and 10 mg L- 1) were applied to hydroponically grown lettuce (Lactuca sativa L. cv. Ferdos) under three concentrations of Cd toxicity (0, 2.5, and 5 mg L- 1). RESULTS: The results showed that along with increasing concentrations of zinc in the nutrient solution, growth traits such as plant performance, chlorophyll index (SPAD), minimum fluorescence (F0), leaf zinc content (Zn), leaf and root iron (Fe) content, manganese (Mn), copper (Cu), and cadmium increased as well. The maximum amounts of chlorophyll a (33.9 mg g- 1FW), chlorophyll b (17.3 mg g- 1FW), carotenoids (10.7 mg g- 1FW), maximum fluorescence (Fm) (7.1), and variable fluorescence (Fv) (3.47) were observed in the treatment with Zn without Cd. Along with an increase in Cd concentration in the nutrient solution, the maximum amounts of leaf proline (5.93 mmol g- 1FW), malondialdehyde (MDA) (0.96 µm g- 1FW), hydrogen peroxide (H2O2) (22.1 µm g- 1FW), and superoxide dismutase (SOD) (90.3 Unit mg- 1 protein) were recorded in lettuce treated with 5 mg L- 1 of Cd without Zn. Additionally, the maximum activity of leaf guaiacol peroxidase (6.46 Unit mg- 1 protein) was obtained with the application of Cd at a 5 mg L- 1 concentration. CONCLUSIONS: In general, an increase in Zn concentration in the nutrient solution decreased the absorption and toxicity of Cd in lettuce leaves, as demonstrated in most of the measured traits. These findings suggest that supplementing hydroponic nutrient solutions with zinc can mitigate the detrimental effects of cadmium toxicity on lettuce growth and physiological processes, offering a promising strategy to enhance crop productivity and food safety in cadmium-contaminated environments.


Assuntos
Cádmio , Clorofila , Hidroponia , Lactuca , Zinco , Lactuca/efeitos dos fármacos , Lactuca/crescimento & desenvolvimento , Lactuca/metabolismo , Cádmio/toxicidade , Zinco/metabolismo , Clorofila/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Fotossíntese/efeitos dos fármacos
3.
BMC Plant Biol ; 24(1): 121, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373932

RESUMO

BACKGROUND: The primary challenge in the cut flower industry, specifically in the postharvest phase, is the short vase life of flowers. This issue, along with early leaf yellowing and perianth abscission, significantly diminishes the economic value of flowers due to their accelerated senescence. To tackle this, we conducted a factorial experiment on Alstroemeria cv. Rebecca, utilizing a completely randomized design with three replications. In this experiment the effects of varying concentrations of Salicylic acid (SA) (0, 1.5, and 3 mM) and sucrose (SU) (0% and 3%) were investigated on the postharvest quality of leaves and florets, with systematic evaluations every three days throughout their vase life. RESULTS: This experiment revealed that the specific treatment combination of 1.5 mM SA + 3% SU (T5) markedly improved various parameters, such as vase life, total chlorophyll content, membrane stability index, relative fresh weight, and water uptake of cut flowers. In our analysis, we observed that this preservative solution not only extended the vase life and enhanced water uptake but also effectively preserved total chlorophyll, mitigated the loss of fresh weight, and reduced membrane deterioration in petals. Additionally, our results showed an increase in the activities of catalase (CAT) and peroxidase (POD) enzymes, as well as total protein content, alongside a decrease in malondialdehyde (MDA) and hydrogen peroxide (H2O2) levels. Moreover, this study noted a decrease in microbial populations in solutions containing different concentrations of salicylic acid. CONCLUSIONS: Our research demonstrated that alstroemeria flowers maintained in a solution with 1.5 mM SA + 3% SU exhibited a significantly prolonged vase life of up to 21 days, in contrast to the 15 days observed in control flowers kept in water. These results are highly beneficial for manufacturers in the cut flower industry, as they provide a viable method to substantially extend the vase life of cut flowers. Such an enhancement in flower longevity can lead to increased market value and customer satisfaction. Furthermore, the reduction in flower senescence and decay rates can contribute to decreased waste and greater efficiency in cut flower distribution and sales, offering a substantial advantage to manufacturers in this competitive market. The extended vase life and reduced senescence observed in alstroemeria flowers treated with 1.5 mM SA and 3% SU are attributed to SA's role in enhancing endogenous defense responses and sucrose's function as an energy source, collectively improving water uptake, and delaying the natural decay process.


Assuntos
Alstroemeria , Alstroemeria/metabolismo , Sacarose/farmacologia , Ácido Salicílico/farmacologia , Peróxido de Hidrogênio/farmacologia , Flores/metabolismo , Água/metabolismo , Clorofila
4.
BMC Plant Biol ; 24(1): 140, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413882

RESUMO

BACKGROUND: Drought and heat stress are significant concerns to food security in arid and semi-arid regions, where global warming is predicted to increase both frequency and severity. To cope with these challenges, the use of drought-tolerant plants or technological interventions are essential. In this study, the effects of foliar potassium nitrate (KNO3) application on the stress tolerance and recovery of Myrobalan 29C rootstocks (Prunus cerasifera Ehrh.) were evaluated. These rootstocks are widely recognized for their adaptability and are extensively used in fruit production. To assess their response, the rootstocks were subjected to drought, heat shock, or a combination of both stressors. Additionally, they were treated with 1.0% KNO3 via foliar application. Throughout the stress and recovery periods, various morphological, physiological, and bio-chemical parameters were measured. RESULTS: Based on our results, KNO3 treatment improved LRWC, Chl stability, SC, and key stress markers like proline, MDA, H2O2, along with antioxidant enzymes CAT, SOD, POD during both stress and recovery phases. Moreover, our results emphasized KNO3's critical role in hormone regulation under stress. KNO3 application significantly altered hormone levels, notably increasing ABA during drought and heat shock stress, essential for stress response and adaptation. In contrast, IAA, GA, and cytokinin's significantly increased during the recovery phase in KNO3-treated plants, indicating improved growth regulation and stress recovery. In addition, KNO3 application improved the recovery process of the rootstocks by restoring their physiological and biochemical functions. CONCLUSION: This study suggests that the application of foliar KNO3 is an effective technique for enhancing the drought and heat tolerance as well as the recovery of Myrobalan 29C rootstocks. These results hold significant value for farmers, policymakers, and researchers, as they offer crucial insights into the development of drought-tolerant crops and the management of climate change's adverse effects on agriculture.


Assuntos
Nitratos , Compostos de Potássio , Estresse Fisiológico , Terminalia , Secas , Peróxido de Hidrogênio/farmacologia , Resposta ao Choque Térmico , Hormônios/farmacologia
5.
Physiol Plant ; 176(4): e14437, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39004804

RESUMO

Drought represents the predominant and most critical abiotic stress challenge within the domain of viticulture, necessitating the identification and application of efficacious strategies to ameliorate its deleterious effects. In the contemporary realm of abiotic stress management, the deployment of α-lipoic acid (α-Lipo), known for its antioxidant capabilities, as an exogenous treatment has been investigated for mitigating various abiotic stresses in numerous plant species, yet a detailed exploration of its efficacy in alleviating drought stress in grapevines remains to be conclusively determined. This study aimed to elucidate the adaptive mechanisms against drought stress by examining the effects of different α-Lipo concentrations (0, 1, 25 and 50 µM) applied on the foliar under well-irrigated and drought conditions on American grapevine rootstocks '1103 P' (drought tolerant) and '3309 C' (drought sensitive). Our findings revealed that the efficacy of α-Lipo varied significantly depending on rootstock type and irrigation status. 1103 P rootstock treated with 1 µM α-Lipo under well-irrigated conditions showed greater positive effects on growth traits, photosynthetic and osmotic parameters. In contrast, in rootstock 3309 C under the same conditions, the highest effects were obtained at 25 and 50 µM α-Lipo concentrations. Under drought stress conditions, 50 µM α-Lipo treatment improved physiological parameters (chlorophyll content, proportional water coverage and stomatal conductance), proline content and antioxidant enzyme activities (SOD, CAT and APX), while reducing electrolyte leakage and MDA levels in both rootstocks, showing a strong potential to increase oxidative stress tolerance and sustain plant growth. Heatmap visualization analysis confirmed the data obtained from Principal Component Analysis (PCA) and revealed that 1103 P treated with 50 µM α-Lipo under drought stress conditions exhibited superior physiological performance compared to 3309 C under the same conditions. This indicates the importance of potential rootstock differences in stress adaptation or α-Lipo uptake efficiency. These findings suggest that α-Lipo holds promise as an eco-friendly, natural bio-stimulant for use in arid environments, contributing to the advancement of sustainable agricultural practices in the foreseeable future.


Assuntos
Antioxidantes , Secas , Estresse Oxidativo , Raízes de Plantas , Ácido Tióctico , Vitis , Vitis/efeitos dos fármacos , Vitis/fisiologia , Ácido Tióctico/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Antioxidantes/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Folhas de Planta/metabolismo
6.
BMC Plant Biol ; 23(1): 560, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37957557

RESUMO

BACKGROUND: Rosa damascena is extensively cultivated in various regions of Iran due to its aesthetic attributes, medicinal qualities, and essential oil production. This study investigated the efficacy of Ascophyllum nodosum extract (AnE) at concentrations of 0, 2, and 3 g L- 1 and Nano-silicon (nSiO2) at concentrations of 0, 50, and 100 mg L- 1 in ameliorating the impact of salinity on two genotypes of Damask rose ('Chaharfasl' and 'Kashan') under in vitro culture conditions. Additionally, various physio-chemical characteristics of R. damascena explants were assessed. RESULTS: The findings revealed that exposure to 100 mM NaCl resulted in a substantial reduction in the Relative Water Content (RWC), Membrane Stability Index (MSI), leaf pigments (Chlorophyll b, Chlorophyll a, total Chlorophyll, and carotenoids), chlorophyll fluorescence parameters, and protein content in both genotypes when compared to control conditions. Salinity induced a significant increase in the parameter F0 and a decrease in the parameter Fv/Fm compared to the control conditions in both genotypes. Nonetheless, the genotype Kashan treated with 3 g L- 1 AnE + 100 mg L- 1 nSiO2 exhibited the maximum Fm value under control conditions, with a significant difference compared to other treatments. Furthermore, salinity caused a considerable reduction in Fm in both 'Kashan' and 'Chaharfasl' by 22% and 17%, respectively, when compared to the control condition. 'Kashan' displayed the maximum Fv/Fm compared to the other genotype. The maximum levels of Malondialdehyde (MAD) and hydrogen peroxide (H2O2) were also observed in explants affected by salinity. The combination of 3 g L- 1 AnE + 100 mg L- 1 nSiO2, followed by 2 g L- 1 AnE + 100 mg L- 1 nSiO2, exhibited substantial positive effects. Salinity also led to an increase in proline content and the activity of peroxidase (POD), superoxide dismutase (SOD), guaiacol peroxidase (GPX), and catalase (CAT) in both genotypes. The activity of these enzymes was further enhanced when AnE was applied at concentrations of 2 and 3 g L- 1 in combination with 100 mg L- 1 nSiO2. CONCLUSIONS: The 'Kashan' genotype displayed greater tolerance to salinity by enhancing water balance, maintaining membrane integrity, and augmenting the activity of antioxidant enzymes compared to 'Chaharfasl'. The utilization of nSiO2 and AnE biostimulants demonstrated potential benefits for R. damascena, both under salinity and control conditions. These findings hold substantial importance for researchers, policymakers, and farmers, offering valuable insights into the development of salinity-tolerant crop varieties.


Assuntos
Ascophyllum , Rosa , Rosa/metabolismo , Salinidade , Clorofila A , Silicones , Peróxido de Hidrogênio/metabolismo , Antioxidantes/metabolismo , Clorofila/metabolismo , Água
7.
Pediatr Cardiol ; 44(3): 647-655, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35984471

RESUMO

In myocarditis, the search for effective and appropriate prognostic biomarkers can help clinicians identify high-risk patients in a timely manner and make better medical decisions in clinical practice. The prognostic value of systemic immune-inflammatory index (SII), an innovate biomarker of inflammation, in fulminant myocarditis in children has not been assessed. This study aims to (1) determine the effect of SII and other inflammatory markers on the prognosis of patients with myocarditis, and (2) characterize other factors affecting adverse outcomes in myocarditis. All patients aged between 1 months and 18 years who admitted to Pediatric Emergency Department between January 1, 2015 and October 1, 2021 and were diagnosed with myocarditis were retrospectively analyzed. 106 Eligible subjects were enrolled (67% male, 12.5 years (IQR 6-16). Fulminant myocarditis developed in 16 (15%) of the patients. The median SII was 1927 (1147.75-3610.25) in the fulminant myocarditis group and 351 (251.75-531.25) in the non-fulminant group (p < 0.001). In estimation of fulminant myocarditis, AUC was 0.87 for WBC [95% confidence interval (CI) 0.72-1.00, p = 0.002], 0.94 for ANC (95% CI 0.85-1.00), p = 0.000), 0.92 for SII (95% CI 0.82-1.00, p = 0.000). Spearman's correlation analysis showed a significant negative correlation between SII and LVEF (r = 0.576, p < 0.001). The highest AUC values were associated with ANC, SII, and WBC levels to predict fulminant myocarditis. SII, a readily available biomarker from routine blood parameters, allows early recognition of negative outcomes and can independently predict the prognosis of myocarditis in children.


Assuntos
Miocardite , Criança , Humanos , Masculino , Lactente , Feminino , Miocardite/diagnóstico , Estudos Retrospectivos , Inflamação , Prognóstico , Hospitalização
8.
Int J Biometeorol ; 66(5): 987-994, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35124758

RESUMO

The frequency and severity of spring frosts increase during the budburst in many regions of the world as global warming increases. Variability in the freezing resistance of sweet cherry flower organs during the active growing period has been rarely documented, especially in regard to the sepal, pedicel, receptacle, petal, stamen, and pistil organs of flower at the deacclimation stage. The freezing resistance of flower organs of six sweet cherry cultivars was investigated at regular intervals from the first white stage through the full bloom stage using differential thermal analysis (DTA) for 2019-2020. For most of the cultivars, petal and stamen organs of flower exhibited higher freezing resistance than other flower organs. There were significant differences in frost tolerance among cultivars, and 'Van' and 'Wild Genotype' had a lower level of low temperature exotherms or critical temperatures (LT50 values) in both stages, whereas 'Merton Late' was more sensitive to frost than other cultivars. Additionally, an increase in LT50 values in all cultivars was observed with the progression of the budburst. The results in the present study can increase the certainty of decision-making regarding the timing and methods to increase the air temperature in orchards during spring frost events to prevent frost damage. Larger data sets are required to further validate our results, and future efforts should thus be focused on determining the critical temperatures of flower organs using different measurement techniques.


Assuntos
Prunus avium , Temperatura Baixa , Análise Diferencial Térmica , Flores , Temperatura
9.
Int J Biometeorol ; 65(7): 1125-1135, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33611681

RESUMO

Many studies to date on the response of cherry flower buds to frost have focused on visual evaluations by observing tissue browning after frost event in the orchard and laboratory conditions but only little knowledge is available on the consequences of intracellular ice formation on cellular ultrastructure that underlies exothermic reactions during bud burst stages. In this study, the differential thermal analysis (DTA) method was used to investigate critical frost temperatures for the sweet cherry cultivars '0900-Ziraat', 'Erzincan Macar', 'Lambert', 'Vista', 'Stella', and 'Early Burlat' under laboratory-based freeze assays. In the course of our experimental study, frost tolerance or cell death points (CDPs) of flowers of six cherry cultivars were investigated in consecutive phenological stages from the start to the end of blooming, for 2 years. The frost tolerance of flower buds changed according to different developmental stages and cherry cultivars. Our results of frost tolerance tests performed on the cherry blooming stages are rather controversial. Our findings have shown that at the open cluster stage, the frost tolerance of the flower buds is very sensitive (mCDP = -1.18°C for 'Lambert'), while the first white stage has revealed an important increase (mCDP= -9.96°C for '0900-Ziraat') in the frost tolerance of those. Averaged over 2 years, the temperatures causing 50% frost damage for flower buds were -2.08 to -3.76°C at the side green stage, -1.49 to -3.22°C at the green tip stage, -1.18 to -1.98°C at the open cluster stage, -7.92 to -9.96°C at the first white stage, and -6.29 to -9.36°C at the full bloom stage in the range of six cultivars. Based on our test results, '0900-Ziraat' and 'Vista' were regularly classified as frost-tolerant cultivars. The flower buds of 'Lambert' and 'Early Burlat' have been regularly the most sensitive, while 'Erzincan Macar' and 'Stella' were ranked into the group of medium sensitivity. These results can help farmers to estimate possible frost damages on sweet cherry flower buds due to frost events at the investigated phenological stages.


Assuntos
Prunus avium , Análise Diferencial Térmica , Flores , Congelamento , Temperatura
10.
Int J Biometeorol ; 65(12): 2157-2170, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34324064

RESUMO

To the better management of spring frost problem in the apricot cultivars, evaluation of biochemical changes in flower and/or flower organs during bud break could be one of the key factors. In this study, the relationship between the biochemical metabolites such as amino acids and minerals in the receptacle and pistil organs of two different apricot cultivars (frost-sensitive and frost-tolerant) and their relative effects on the frost tolerance of the cultivars and their organs were investigated during full blooming stage. In both apricot cultivars, it was found that the cell death points (CDP) of flower receptacle (- 6.3 to - 8.4 °C) were at higher temperatures than the CDP of flower pistil organs (- 13.1 to - 14.5 °C). Receptacle organs in flower, therefore, had less tolerance to spring frost damage. In addition, significant differences in mineral and amino acid contents were detected both between apricot cultivars and between the receptacle and pistil organs of the cultivars. Amino acid and mineral contents were lower both in the freezing-sensitive apricot cultivar ("Mihralibey") and the freezing-sensitive organ (receptacle) in comparison with the freezing-tolerant apricot cultivar ("Igdir Salak") and the freezing-tolerant organ (pistil). A significant negative correlation was also observed between the mean CDP values and both amino acid and mineral contents in the receptacle and pistil organs of both apricot cultivars. A negative correlation was found between CDP values and glutamate from amino acids and N, K, and Mg from minerals, and also these were determined that they had positive effects on frost tolerance increase. An important finding from our work revealed that the amount of each mineral and amino acid allocated differently to the receptacle and pistil organs of the apricot cultivars. The understanding of the amino acids and the mineral dynamics may contribute to improving the tolerance of flowers of apricot or other deciduous species to frost damage during spring. In the future, we may conclude that protection strategies such as increasing amino acids and mineral content in the receptacle organ of flowers would be necessary to cope with the negative effects of spring frost.


Assuntos
Prunus armeniaca , Aminoácidos , Morte Celular , Flores , Minerais
11.
Echocardiography ; 37(8): 1251-1257, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32686862

RESUMO

BACKGROUND: Tricuspid annular plane systolic excursion (TAPSE) and mitral annular plane systolic excursion (MAPSE) are two echocardiographic parameters which provide reliable information about the longitudinal myocardial functions of the right and left ventricles in both adult and pediatric population. The aim of this study was to determine the TAPSE and MAPSE reference values in healthy children aged 0-18 years. METHODS AND RESULTS: This prospective study included 1300 healthy children evaluated with two-dimensional echocardiography. In addition to routine echocardiographic examination, the right and left ventricular systolic functions were assessed by TAPSE and MAPSE measurements. Statistical analyses were carried out in the groups of subjects stratified according to age and body surface area. The mean and standard deviation values and z-scores of TAPSE and MAPSE were developed in each group. CONCLUSIONS: The determination of reference values for TAPSE and MAPSE in healthy children will be of guidance in the evaluation of both healthy children and those with congenital or acquired heart diseases in which the right and left ventricular systolic functions are affected. The reference values obtained will contribute to the clinical practice and the future studies.


Assuntos
Ecocardiografia , Valva Tricúspide , Adulto , Criança , Humanos , Estudos Prospectivos , Valores de Referência , Sístole , Valva Tricúspide/diagnóstico por imagem , Função Ventricular Direita
12.
Echocardiography ; 35(2): 227-233, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29205484

RESUMO

OBJECTIVE: Cardiac dysfunction is a well-known consequence of diabetes mellitus. This study was designed to assess whether type 1 diabetic children and adolescents with good metabolic control have early echocardiographic signs of subclinical left ventricular dysfunction and whether diabetes duration has any influence, using conventional and nonconventional echocardiographic tools. METHODS: A total of 100 patients with type 1 diabetes mellitus and 80 gender- and age-matched healthy controls were included. The cases underwent standard conventional transthoracic echocardiography, tissue Doppler imaging, and two-dimensional speckle tracking echocardiography. None of the diabetic patients had signs of renal, retinal, or neurological complications of the disease, and all were good metabolic control (mean HbA1c <7.5%). RESULTS: There was no difference among groups in relation to age, sex, body mass index, and blood pressure. Conventional echocardiographic parameters were similar between diabetic and nondiabetic subjects except increased mitral valve peak A-wave and significantly lower mitral E/A ratio in diabetics. Diabetic patients had more advanced diastolic dysfunction with TDI analysis. In the diabetic group, left ventricular global longitudinal, circumferential, and radial strain and strain rate were significantly lower compared with the controls. There was a positive correlation between diabetes duration and cardiac dysfunction. CONCLUSION: The results of this study showed that the diabetic children and adolescents with good metabolic control had diastolic dysfunction when assessed with either conventional or tissue Doppler echocardiography. Also diabetic patients had subclinical LV systolic dysfunction with a normal LVEF which can be detected with 2D speckle tracking echocardiography.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/fisiopatologia , Ecocardiografia/métodos , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/fisiopatologia , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Diástole , Feminino , Humanos , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes , Sístole , Disfunção Ventricular Esquerda/diagnóstico por imagem
13.
Pediatr Cardiol ; 39(4): 718-725, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29340731

RESUMO

To analyze the role of sensitive cardiac troponin I (scTnI) and high-sensitive troponin T (hscTnT) in the determination of myocardial injury caused by volume and pressure load due to pulmonary hypertension (PH) and to investigate if these markers may be useful in the management of PH in childhood. Twenty-eight patients with congenital heart disease (CHD) with left to right shunt and PH, 29 patients with CHD with left to right shunt but without PH, and 18 healthy children, in total 75 individuals, were included in the study. All cases were aged between 4 and 36 months. Echocardiographic evaluation was performed in all cases, and invasive hemodynamic investigation was performed in 33 cases. Blood samples were obtained from all cases, for the measurement of brain natriuretic peptide (BNP), pro-brain natriuretic peptide (pro-BNP), sensitive cardiac troponin I (scTnI), and high-sensitive troponin T (hscTnT) levels. The mean BNP, pro-BNP, scTnI, and hsTnT levels were statistically significantly higher in patients with PH than in the patients without PH (p < 0.001). A statistically significant positive correlation was determined between pulmonary artery systolic pressure and scTnI and hscTnT levels (r = 0.34 p = 0.01, r = 0.46 p < 0.001, respectively) levels. Pulmonary hypertension determined in congenital heart diseases triggers myocardial damage independently of increased volume or pressure load and resistance, occurring by disrupting the perfusion via increasing ventricular wall tension and the myocardial oxygen requirement. Serum scTnI and hscTnT levels may be helpful markers to determine the damage associated with PH in childhood.


Assuntos
Biomarcadores/sangue , Cardiopatias Congênitas/complicações , Hipertensão Pulmonar/sangue , Troponina I/sangue , Troponina T/sangue , Angiografia/métodos , Pré-Escolar , Ecocardiografia/métodos , Feminino , Cardiopatias Congênitas/sangue , Hemodinâmica/fisiologia , Humanos , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/etiologia , Lactente , Masculino , Miocárdio/patologia , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Curva ROC , Sensibilidade e Especificidade
14.
Echocardiography ; 34(3): 436-440, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28052532

RESUMO

BACKGROUND: This study focuses on determining concomitant persistent left superior vena cava (SVC) in patients with congenital heart disease (CHD). METHODS: Between 2005 and 2012, a total of 2.663 patients with CHD, 88 (3.3%) of whom were diagnosed with persistent left SVC, were evaluated retrospectively. The demographic characteristics of patients, clinical and radiographic findings, echocardiography, cardiac catheterization, and angiography results obtained from the patients' records were reviewed. RESULTS: The median age of the patients was 9.5 months, and 46 of the 88 (52.3%) patients were female. The most common concomitant CHD were ventricular septal defect, double outlet right ventricle (DORV), and tetralogy of Fallot (TOF). When the patients were compared according to their CHD, persistent left SVC frequency was significantly higher in those with DORV (P<.001), TOF (P=.04), patent ductus arteriosus (P=.01), and atrial septal defect (P=.03). Eighty-three of the 88 (94.3%) patients with persistent left SVC had right SVC, and 5 (5.7%) had absence of the right SVC. Twenty-seven of the 83 (32.5%) patients with double SVC had connected normal innominate vein. In all cases, right aortic arch association was seen in 14 (15.9%) patients. Eighty-four (95.4%) of the patients were diagnosed by echocardiography prior to catheter angiography. Persistent left SVC drained to the coronary sinus in all cases. CONCLUSION: Increased awareness about the association of certain CHD with persistent left SVC and a careful echocardiographic examination can facilitate the diagnosis of persistent left SVC. In addition, precise prior diagnosis of persistent left SVC can prevent complications during surgery.


Assuntos
Ecocardiografia , Cardiopatias Congênitas/diagnóstico por imagem , Malformações Vasculares/diagnóstico por imagem , Veia Cava Superior/anormalidades , Veia Cava Superior/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/complicações , Humanos , Lactente , Masculino , Estudos Retrospectivos , Centros de Atenção Terciária , Malformações Vasculares/complicações
15.
Front Plant Sci ; 15: 1321210, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525141

RESUMO

Sugars and organic acids not only have a significant impact on taste balance and sensory acceptance by consumers but also play a crucial role in the chemical equilibrium of grape juices and wines. Therefore, this study aimed to quantify the content and composition of sugars and organic acids in 17 grape varieties over two consecutive years using high-performance liquid chromatography. The variability in all the parameters studied was strongly influenced by both the grape cultivars and specific years (p ≤ 0.05). In grape berries, the primary sugars identified were fructose and glucose, which ranged from 6.50 to 11.10 g/L and from 5.83 to 12.12 g/L, respectively, over the two years. However, sucrose was not detected in any of the grape varieties examined. For the two respective years, the highest titratable acidity (TA) was found in Tekirdag Çekirdeksizi (TeCe) (0.89 and 0.90 g/L), while the lowest was detected in Victoria (Vi) (0.48 and 0.51 g/L). Total soluble solids (TSS) peaked in Horoz Karasi (HoKA) (21.90 °Brix), whereas it reached its lowest point in Big Perlon (BiPe) (14.1 °Brix). The tartaric acid content in the grape berries, ranging from 1.48 to 10.33 g/L for the two years, exhibited similar characteristics to malic acid, which ranged from 1.09 to 9.62 g/L and from 1.03 to 9.68 g/L for the two respective years. The succinic, malic, tartaric, citric, and oxalic acid contents were notably higher in the Kyoho (Ky) variety than in the other varieties. When examining the dendrogram of the contents of organic acid and sugar for similarities, it was evident that 16 out of the 17 grape varieties had a high degree of similarity, except for Alphonse Lavallée (AlLa) and HoKa. The similarity levels among the varieties ranged from 99.49% to 72.36%. The highest similarity (99.49%) was observed between the AlLa and Baris (Ba) varieties. The lowest similarity was observed among the AlLa, HoKa, and Ky varieties. In summary, this study underscores that certain table grape varieties grown in Ankara exhibit significant variations in valuable organic acids and sugars, which are associated with potential health benefits when considering human consumption.

16.
Ecol Evol ; 14(5): e11361, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38774135

RESUMO

Riparian woody plant communities, including shrubs and trees, are essential for maintaining biodiversity, protecting against floods, reducing erosion, and transporting nutrients. However, these habitats are greatly threatened by human activities, particularly agricultural land acquisition, and the introduction of invasive species. This study examined species diversity and interspecific association in riparian woody plant communities along rivers in the Romanian Carpathians. The study focused on communities of Salix purpurea, S. alba, and Hippophaë rhamnoides in mountain regions, with varying sampling efforts at different sites for each species. A total of 174 plant species were found, predominantly herbaceous (77.9%), followed by trees (11.6%) and shrubs (10.5%). While S. alba and S. purpurea communities show high species richness and abundance, S. alba has slightly higher diversity (H' ≈ 2.23, SD = 0.28) than S. purpurea (H' ≈ 1.69, SD = 0.42). Contrarily, significant differences exist between H. rhamnoides and S. alba communities in species richness (p = .007) and Shannon diversity (p = .004). PCA analysis elaborated on distinct distribution patterns of plant associations within habitats S. purpurea community, H. rhamnoides community, and S. alba community. Four invasive species (Oenothera biennis L. and Oxalis stricta L. in S. alba communities, Reynoutria sachalinensis Nakai in both S. purpurea and H. rhamnoides communities, and Erigeron canadensis L. in H. rhamnoides communities) were identified, as requiring conservation efforts. Hemicryptophytes dominate species richness, while microphanerophytes and megaphanerophytes significantly contribute to plant abundance. H. rhamnoides formed Hippophaë rhamnoides dunes (2160) Natura 2000 habitat, while S. alba created galleries within the 92A0 Salix alba and Populus alba habitat. In conclusion, the findings from this study highlight the importance of preserving riparian habitats because their value goes beyond local or regional considerations and extends to the global scale due to their unique characteristics.

17.
Front Plant Sci ; 15: 1379328, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828219

RESUMO

The dynamic fluctuations in autumn temperatures, particularly the marked diurnal variations and the subsequent precipitous drops are key and a pivotal role in viticulture, as they critically influence the acclimation process of grapevines to cold, thereby directly impacting their survival and productivity in cold-climate regions. In this comprehensive study, we investigated the cold hardiness of four grapevine cultivars: 'Itasca', 'Frontenac', 'La Crescent', and 'Marquette', focusing on how these cultivars and their individual buds (1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, and 9th) respond to fluctuating weather and low temperatures typical of autumn [-1.1°C (30°F) -9.4°C (15°F) and -17.8°C (0°F)]. Our results illuminated the striking variability in cold hardiness that was manifest not only among the different cultivars but also within individual buds on the same vine, underscoring the critical influence of bud position on a vine for cold hardiness. 'Frontenac' showed greater cold hardiness at critical temperatures at which 10%, and 50% of the dormant buds were lethally affected by cold (LT10 and LT50) compared to 'Itasca' and 'La Crescent', with 'Marquette' exhibiting intermediate values. However, in cultivars such as 'Itasca' and 'Marquette', certain buds demonstrated a pronounced hardiness when faced with colder temperatures, while others exhibited a heightened sensitivity, thereby revealing a nuanced interplay between bud position and a vine's ability to withstand cold stress. Our study revealed a notable divergence from traditional viticulture understanding; apical buds demonstrated greater cold hardiness than basal buds and opened new paths for research into grapevine physiology. Our results also indicated a significant trend wherein older vines across all studied cultivars displayed enhanced cold hardiness, particularly pronounced at the critical LT50 and the critical temperature at which 90% of the dormant buds were lethally affected by cold (LT90) thresholds, in comparison to younger vines. Moreover, our findings shed light on the impact of autumn's diurnal temperature variations and the subsequent drop in temperatures on vine cold hardiness, thus highlighted the complex interplay between environmental temperature dynamics and dormant bud hardiness. In conclusion, our study showed that the cold damage observed in grapevines in North Dakota was not a result of extreme temperature fluctuations in the fall. This was confirmed by testing the vines after they had reached various threshold temperatures through differential thermal analysis (DTA) and optical differential nucleation and expansion analysis (ODNEAL) methodologies, particularly before the onset of severe pre-winter cold conditions. These comprehensive findings highlighted the complexity of the vine's response to climatic conditions and viticultural management, pointing to the need for specific strategies in vineyard management and cultivar selection to optimize bud hardiness and productivity in the face of various environmental challenges, especially in cold climate viticulture.

18.
Plants (Basel) ; 13(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38931044

RESUMO

Unraveling the intricate physiological and biochemical intricacies associated with female dominance in grape berries across diverse developmental stages is imperative for optimizing grape production and ensuring the attainment of high-quality yields. This study conducted a thorough analysis of grape berries across phenological stages (BBCH-79, BBCH-81, BBCH-89) and cultivars. At BBCH-89, Bozcaada Çavusu*Vasilâki demonstrated the highest berry weight and total soluble solids (TSS) levels, emphasizing its enological potential. Acidity peaked at BBCH-79 (28.16) and declined at BBCH-89 (6.11), signaling a shift towards lower acidity in later stages. Bozcaada Çavusu*Vasilâki consistently showed the highest maturity index (MI). Mineral content variations were observed across nitrogen (N), calcium (Ca), potassium (K), phosphorus (P), magnesium (Mg), sulfur (S), iron (Fe), manganese (Mn), boron (B), zinc (Zn), and copper (Cu), with Bozcaada Çavusu*Vasilâki often having the highest concentrations, particularly in potassium, calcium, and boron. Hormonal analysis revealed a significant surge in concentrations at BBCH-89, with Bozcaada Çavusu*Vasilâki standing out. Notably, Indole-3-acetic acid (IAA) concentrations increased by 106%, and abscisic acid (ABA) levels peaked at BBCH-79 with a 38% increase in Bozcaada Çavusu*Kuntra. Sugar content analysis showed variations in fructose, glucose, sucrose, rhamnose, xylose, galactose, and arabinose levels across sampling times and cultivars. Bozcaada Çavusu*Vasilâki consistently exhibited higher sugar levels, especially at BBCH-81 and BBCH-89. Vitamin concentrations varied temporally and among cultivars, with BBCH-89 displaying the highest vitamin A concentration (6.24 mg/100 g FW), and Bozcaada Çavusu*Vasilâki often exhibiting maximum values for vitamin B1, B2, B6, and C. Further research and targeted cultivation practices focusing on the unique attributes of Bozcaada Çavusu*Vasilâki could enhance grape production efficiency, emphasizing its potential contribution to achieving consistently high-quality yields across various phenological stages.

19.
Clin Lab ; 59(9-10): 1045-51, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24273927

RESUMO

BACKGROUND: Neonatal sepsis is one of the leading causes of neonatal morbidity and mortality in the newborn period. The purpose of this study was to compare a rapid bed-side test against central laboratory analysis for CRP in newborn infants with suspicion of sepsis. METHODS: We included 23 newborn infants with suspected or proven sepsis (group 1). Age and gender matched 40 infants without sepsis were assigned as controls (group 2). A total of 116 blood samples (58 samples from each group) were drawn from the peripheral vein for C-reactive protein (CRP) measurements. For the NycoCard CRP tests, 5 microL of whole blood and the same amount of serum was used to determine the CRP value (wCRP-N and sCRP-N). As the reference CRP test, serum concentrations of CRP (CRP-Lab) were simultaneously measured by immunonephelometric method requiring 1 mL of serum sample. CRP values > or = 10 mg/L were considered positive for all three tests. RESULTS: It was found that the median values of wCRP-N (18.9 mg/L), sCRP-N (25 mg/L), and CRP-Lab (22.2 mg/L) of group 1 were higher than group 2 (wCRP-N: 1.1 mg/L, sCRP-N: 5 mg/L, and CRP-Lab: 2.9 mg/L) (p < 0.001). Nycocard-CRP were positively correlated with CRP-Lab. With considering CRP-Lab positive at > 10 mg/L, both CRP-NycoCard tests have high sensitivity and specificity, although sCRP-N has slightly higher predictive values. Passing-Bablok regression and Bland-Altman analysis showed that NycoCard tests have no statistically significant systematic proportional bias. CONCLUSIONS: Nycocard-CRP tests have high predictive values, require a very small amount of blood, and results can be obtained quickly. Determinations of CRP concentrations by NycoCard-CRP test seems to be helpful in distinguishing septic and aseptic newborns.


Assuntos
Proteína C-Reativa/análise , Doenças do Recém-Nascido/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Sepse/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Recém-Nascido , Doenças do Recém-Nascido/sangue , Masculino , Sensibilidade e Especificidade , Sepse/sangue
20.
Echocardiography ; 35(4): 580, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29679448
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