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1.
Catheter Cardiovasc Interv ; 103(6): 1074-1077, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38577923

RESUMEN

Transcatheter aortic valve implantation (TAVI) has traditionally been indicated for the treatment of aortic stenosis. However, in this case report, we describe a successful TAVI procedure in a 46-year-old male patient who had previously undergone David aortic valve-sparing aortic root replacement for type 1 aortic dissection. The patient presented with aortic valve insufficiency 4 years after the initial surgery and was subsequently treated with a 34 mm Medtronic CoreValve Evolut R prosthesis via TAVI. This case highlights the feasibility of TAVI as a viable treatment option for postoperative aortic valve insufficiency in patients with prior ascending aortic or aortic arch surgery.


Asunto(s)
Disección Aórtica , Insuficiencia de la Válvula Aórtica , Válvula Aórtica , Implantación de Prótesis Vascular , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Masculino , Disección Aórtica/cirugía , Disección Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/etiología , Insuficiencia de la Válvula Aórtica/cirugía , Insuficiencia de la Válvula Aórtica/fisiopatología , Persona de Mediana Edad , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Resultado del Tratamiento , Implantación de Prótesis Vascular/instrumentación , Implantación de Prótesis Vascular/efectos adversos , Válvula Aórtica/cirugía , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/fisiopatología , Diseño de Prótesis , Prótesis Vascular , Aneurisma de la Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta/cirugía , Aneurisma de la Aorta/diagnóstico por imagen , Aortografía
2.
Adv Med Sci ; 69(1): 56-60, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38368744

RESUMEN

PURPOSE: Growth differentiation factor 15 (GDF-15) is a member of the transforming growth factor beta superfamily and is faintly expressed under healthy conditions. GDF-15 is markedly elevated in a variety of diseases, including coronary artery disease (CAD), atrial fibrillation and heart failure. Here, we aimed to investigate the association of GDF-15 with the extent and severity of CAD in patients with stable CAD. METHODS: We enrolled 129 patients undergoing coronary angiography for the evaluation of stable CAD in the study. SYNTAX and SYNTAX II PCI/CABG scores were calculated. The CAD (+) study group was also stratified into two groups (high and low GDF-15) with respect to the mean GDF-15 value. Correlation and regression analyses were performed for further evaluation. RESULTS: Of the 129 patients, 75 had CAD. GDF-15 values were higher in the CAD (+) group (p â€‹< â€‹0.001). The two groups were compared according to a cut-off value of 2451.77. SYNTAX and SYNTAX II PCI/CABG scores were significantly associated with the high GDF-15 group (p â€‹< â€‹0.001). Additionally, correlation analysis showed a strong positive correlation between GDF-15 and SYNTAX (r: 0.859, p â€‹< â€‹0.001), SYNTAX II PCI (r: 0.921, p â€‹< â€‹0.001) and SYNTAX II CABG (r: 0.874, p â€‹< â€‹0.001) scores. Multivariate analysis identified GDF-15 as an independent predictor of CAD. CONCLUSION: GDF-15 is an independent predictor of CAD and is associated with CAD severity in terms of SYNTAX, SYNTAX II PCI and SYNTAX II CABG scores.


Asunto(s)
Angiografía Coronaria , Enfermedad de la Arteria Coronaria , Factor 15 de Diferenciación de Crecimiento , Índice de Severidad de la Enfermedad , Humanos , Factor 15 de Diferenciación de Crecimiento/sangre , Enfermedad de la Arteria Coronaria/patología , Enfermedad de la Arteria Coronaria/sangre , Femenino , Masculino , Persona de Mediana Edad , Anciano , Biomarcadores/sangre , Pronóstico
3.
Environ Monit Assess ; 195(12): 1542, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38012423

RESUMEN

Natural mineral dust episodes elevate particle concentrations and eventually decrease air quality. Air pollutant emissions from aircraft, airport ground operations, and long-range dust transport are producing problems for the aviation sector. Dust transport from the Sahara Desert, one of the primary dust sources globally, significantly affects the eastern Mediterranean basin, including Türkiye. This study investigates the effect of long-range dust transport on particulate matter (PM) concentrations at Turkish airports. Three different approaches were used to analyse dust episodes in the study area. Firstly, routine reports of meteorological conditions at the airports were investigated. For this purpose, airport routine meteorological reports (Metar) and aviation-selected special weather report (Speci) codes, recorded at 11 airports from 2012 to 2021, were used to determine the dust episode days. Secondly, the hourly PM measurement dataset was analyzed from the closest air quality monitoring stations to the airports. Finally, regional atmospheric model results and backward-trajectory analysis were used to validate the dust episodes and determine the dust origin. Results showed that 163 dust episodes occurred during the study period, 17% from North Africa and 12% from the Mediterranean region.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Aeropuertos , Monitoreo del Ambiente/métodos , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Contaminación del Aire/análisis , Polvo/análisis
4.
Environ Monit Assess ; 195(6): 708, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37212911

RESUMEN

Between April 7 and April 10, 2013, a cyclone with a value of 995 hPa that developed in the central Mediterranean transported dust from the Sahara Desert towards Turkey. At 13 airports in Turkey, dust haze and widespread dust were seen during different occasions in this period and caused the observation of so-called "Blowing dust events." This cyclone blew dust towards the Cappadocia airport, and the prevailing visibility decreased to 3800 m, making it the lowest value measured during the transition of this cyclone. In this study, Aviation Routine Weather Report (Metar) and Aviation Selected Special Weather Report (Speci) observations of airports in North Africa and Turkey were evaluated for the period between April 3 and April 11, 2013. With this cyclone the prevailing visibility at Benina Airport in Libya decreased to 50 m on April 6, 2013. This study aims to evaluate long-distance dust transport's effects on meteorological visibility at airports in Turkey and examine the episodic changes of PM10 values measured by air quality monitoring stations. Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model outputs were used to determine the trajectories of long-distance dust particles. Powder red, green, and blue (RGB) and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite images, Cloud-Aerosol LIDAR Infrared Pathfinder Satellite Observations (CALIPSO) images, the Barcelona Supercomputing Center-Dust Regional Atmosphere Model (BSC-DREAM8b) outputs, and Global Forecast System (GFS) synoptic maps were used for analysis. In addition, PM10 values obtained from air quality monitoring stations were examined. According to the data obtained from the CALIPSO images, the dust concentration on the Eastern Mediterranean reaches up to 5 km. The episodic values obtained from certain air quality measurement stations are Adana 701, Gaziantep 629, Karaman 900, Nevsehir 1343, and Yozgat 782 µg/m3 on an hourly average.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Atmosféricos/análisis , Aeropuertos , Arena , Turquía , Monitoreo del Ambiente/métodos , Polvo/análisis , África del Norte , Material Particulado/análisis
5.
Pacing Clin Electrophysiol ; 46(7): 803-810, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37120828

RESUMEN

INTRODUCTION: Sodium-glucose co-transporter 2 (SGLT-2) inhibitors have been shown to reduce the risk of atrial fibrillation (AF) occurrence in patients with diabetes mellitus (DM). In this prospective study, we aimed to analyze the effect of SGLT-2 inhibitors as an add-on therapy to metformin on P wave indices and atrial electromechanics in patients with type 2 DM. METHODS: A total of 144 patients enrolled. Electrocardiographic indices were recorded on admission and at 3rd and 6th month of the combination therapy. P wave indices and atrial electromechanical coupling intervals were measured and compared. RESULTS: Although decrease in P wave dispersion (62.78 ± 9.59 vs. 53.62 ± 10.65; p = .002) became significant at 6th month of combination therapy, significant decreases in P wave terminal force in V1 (37.79 ± 3.45 vs. 32.01 ± 5.74; p = .035), left atrial volume index (35.87 ± 6.57 vs. 31.33 ± 7.31; p = .042), left sided intra-atrial electromechanical delay (32.09 ± 9.17 vs. 27.61 ± 8.50; p = .016), right sided intra-atrial electromechanical delay (31.82 ± 4.92 vs. 27.65 ± 8.05; p = .042), and interatrial electromechanical delay (29.65 ± 7.52 vs. 25.96 ± 4.30; p = .044) were seen as early as 3rd month of treatment. Besides, there was no statistically significant difference between Empagliflozin and Dapagliflozin subgroups in terms of mentioned parameters. CONCLUSION: SGLT-2 inhibitors as an add-on therapy to metformin were shown to significantly improve P wave indices and atrial electromechanics in type 2 DM patients as early as the 3rd month of treatment. It was thought that this may be one of the underlying mechanisms of the decrease in the frequency of AF with the use of SGLT2 inhibitors.


Asunto(s)
Fibrilación Atrial , Diabetes Mellitus Tipo 2 , Metformina , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Fibrilación Atrial/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Metformina/uso terapéutico , Estudios Prospectivos , Atrios Cardíacos
6.
Environ Monit Assess ; 195(2): 304, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36648588

RESUMEN

PM10, one of the air pollutants, occurs regularly in Istanbul during the winter months, namely in December, January, and February. PM10 pollutant is affected by numerous factors. Among these factors are various meteorological variables and climatological factors. This article aims to determine the relationship between PM10 and meteorological variables (wind speed, wind direction, temperature, and relative humidity) and to interpret these results. PM10 and meteorological data were examined between 2011 and 2018. To determine the relationship, multiple linear regression, Pearson's correlation coefficient (PCC), Spearman's rank correlation, Kendall Tau correlation, autocorrelation function (ACF), cross-correlation function (CCF), and visuals were determined using the R program (open-air) packages. In the study, the relationship between wind, temperature, and relative humidity with PM10 was determined, and it was observed that the PM10 concentration was maximum between January and February. PM10 concentrations have a positive relationship with relative humidity and wind direction, while a negative relationship with wind speed and temperature was observed. The correlation values for relative humidity and temperature were found to be 0.01 and - 0.15, respectively. Furthermore, the relationship between wind speed and PM10 was calculated from multiple linear regression model, and the estimated value was - 0.12 while looking at the wind direction value, it was approximately 0.03.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Monitoreo del Ambiente/métodos , Contaminantes Atmosféricos/análisis , Viento , Estaciones del Año , Ciudades , Conceptos Meteorológicos , Material Particulado/análisis
7.
Cardiovasc J Afr ; 34(1): 16-22, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35687085

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) is an infection resulting in very high morbidity and mortality rates globally. Limited data are available on the cardiovascular manifestations in these patients. The aim of this study was to analyse the daily troponin I and D-dimer levels and their impact on the need for intensive care and on mortality rates of COVID-19-infected patients. METHODS: Two-hundred and five patients who were hospitalised between 20 March and 5 May 2020, with a diagnosis of moderate-to-severe COVID-19 pneumonia, were analysed retrospectively. Serum troponin I and D-dimer levels were recorded for at least 10 days after admission. RESULTS: The average age was higher in the group of patients who died compared to the group who were discharged (67.79 ± 14.9 vs 56.87 ± 18.15 years, respectively, p < 0.001). The presence of hypertension, diabetes mellitus, previous coronary bypass surgery, heart failure, chronic renal failure and chronic obstructive pulmonary disease statistically significantly affected mortality rates (p = 0.003, 0.004, 0.045, 0.02, 0.003, 0.007, respectively). The first 10 days of measurements of troponin I and D-dimer were associated with intensive care requirements and mortality (p < 0.001). Both troponin I and D-dimer were higher in the group who died compared to the patients requiring intensive care. Troponin I values of ≥ 16.05 pg/ml on the seventh day were related to the need for intensive care [area under the curve (AUC) 0.896, sensitivity 78.6%, specificity 78.3%, p < 0.001). Troponin I values ≥ 30.25 pg/ml on the ninth day were related to mortality (AUC 0.920, sensitivity 89.5%, specificity 89.3%, p < 0.001). D-dimer values ≥ 878 hg/ml on the second day were associated with intensive care need (AUC 0.896, sensitivity 78.6%, specificity 78.3%, p < 0.001). D-dimer values ≥ 1 106 hg/ml on the 10th day were associated with mortality (AUC 0.817, sensitivity 68.4%, specificity 65.2%, p < 0.001). It was observed that hospitalisation periods ≥ 9.5 days were associated with mortality (AUC 0.738, sensitivity 68.4%, specificity 65.9%, p < 0.001). CONCLUSIONS: We showed that hospitalisations ≥ 9.5 days in duration were related to increased mortality rates. Troponin I and D-dimer follow-up values in the serum were more effective than other inflammatory markers in predicting mortality and the need for intensive care. A high troponin I value should alert the clinician in terms of clinical deterioration.


Asunto(s)
COVID-19 , Mercurio , Neumonía , Humanos , Adulto , Persona de Mediana Edad , Anciano , Troponina I , SARS-CoV-2 , Estudios Retrospectivos
8.
J Electrocardiol ; 72: 44-48, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35306293

RESUMEN

OBJECTIVE: The aim of this study is to examine the probability of de-novo fQRS in patients with mild COVID-19 disease, as an indicator of cardiac injury. METHODS: Data of 256 patients with normal admission electrocardiography and no comorbidities between 1.12.2020-31.12.2021, were examined retrospectively 6-month after mild COVID-19 disease. Patients were divided into two groups: fQRS+ group (n = 102) and non-fQRS group (n = 154). Relation between fQRS and other electrocardiography, echocardiographic and laboratory findings were investigated. RESULTS: No significant difference was found between the groups among age and gender. Troponin-I and creatine kinase myocardial band values (retrospectively 9.10 ± 1.76 vs 0.74 ± 1.43, 34.05 ± 82.20 vs. 14.68 ± 4.42), COVID-19 IgG levels (45.78 ± 14.82 vs. 36.49 ± 17.68), diastolic dysfunction (39.21% vs. 15.07%), EF value (58.02 ± 1.95 vs. 64.27 ± 3.07), dyspnea (41.17% vs. 6.84%), post-COVID-19 tachycardia syndrome (19.6% vs. 2.74) were more frequent in fQRS+ group compared to non-fQRS group. The EF value was lower in the presence of fQRS in the high lateral leads (57.12 ± 1.99, 58.47 ± 1.79, p:0.018). There was a positive correlation between IgG value and endsystolic diameter, septum thickness and left atrium diameter. In multivariate analysis de-novo fQRS, dyspnea, high troponin and IgG values, diastolic dysfunction, low EF value and left atrial diameter were determined as independent risk factors for post-COVID-19 tachycardia syndrome in follow-up. CONCLUSION: In COVID-19 disease de-novo fQRS, dyspnea, high IgG and troponin value, left atrial diameter, lower EF value, diastolic dysfunction were associated with post-COVID-19 tachycardia syndrome. The de-novo fQRS in SARS-COV-2 may be a predictor of future more important adverse cardiovascular outcomes and this should alert clinicians.


Asunto(s)
COVID-19 , Electrocardiografía , Cardiopatías , COVID-19/complicaciones , COVID-19/fisiopatología , Disnea/fisiopatología , Disnea/virología , Estudios de Seguimiento , Cardiopatías/fisiopatología , Cardiopatías/virología , Humanos , Inmunoglobulina G , Estudios Retrospectivos , SARS-CoV-2 , Troponina
9.
Environ Sci Pollut Res Int ; 29(11): 16213-16232, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34647206

RESUMEN

In this study, first, air pollution that is caused by the air pollutants' concentration exceeding the limit value in Istanbul between 2017 and 2020 were analysed. In addition to this analysis, the effects of meteorological parameters on pollution were also examined within the same period of time. Second, for a 14-day period during which the concentration values of the air pollutants were calculated higher than the standards, therefore, were selected as an episode. In that respect, measurements of both pollutant and meteorological parameters were obtained from air quality monitoring stations. The Weather Research and Forecasting (WRF) model was used to examine the changes of meteorological parameters in the surface and upper atmospheric levels. The cross-correlation function (CCF) was performed together with both air quality monitoring station and the WRF model output data to examine the effects of temporal changes in meteorological parameters on air pollutant concentrations on a temporal scale. In addition, some meteorological parameters were obtained from remote sensing systems (SODAR and Ceilometer). Finally, with the help of the trajectory analysis model, it was determined whether the pollutant parameters were transported or not. Consequently, within a 3-year period, the most critical parameters in terms of pollution throughout the city were assessed as NO2 and PM10. Moreover, low wind speeds and high pressure values during the episode prevented the dispersion of pollutants and caused air pollution in Istanbul.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Ciudades , Monitoreo del Ambiente , Material Particulado/análisis , Tiempo (Meteorología)
10.
Environ Monit Assess ; 193(11): 728, 2021 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-34657980

RESUMEN

The research was carried out in the coppice-originated pure oak stands that are being converted to high forests in northwest Turkey. The main goal of the research was to determine the bark thickness (BT) based on tree variables, such as tree diameter at breast height (DBH), total tree height (H), crown diameter (CD), and age (AGE) of the stem sections taken from a total of 350 trees that were destructively sampled from different sites, different oak species (Quercus petraea, Quercus frainetto, Quercus cerris), and different development stages. Models were developed with stepwise multiple regression analysis to predict BT based on the variables. For all oak species, all models obtained by stepwise multiple regression analysis were found to be significant at p = 0.001 level. In Quercus petraea, only the DBH-dependent model explained the variation in BT at a rate of 73%, estimating with an absolute error rate of 21%. The fit statistics of the models (based on DBH and DBH-H explanatory variables) obtained for Quercus frainetto are very close to each other, and they explained the variation in BT at a rate of 69% and estimated with an error rate of 26%. Models (based on DBH and DBH-H explanatory variables) explain the variation in BT in Turkey oak at a rate of 91%, indicating species-specific results. The models based on only DBH can be used with high accuracy to estimate BT.


Asunto(s)
Quercus , Monitoreo del Ambiente , Bosques , Corteza de la Planta , Turquía
11.
Cureus ; 13(8): e17165, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34422502

RESUMEN

Plants belonging to the Ericaceae family, which grow endemically in some parts of the world, contain grayanotoxin, which causes fatal bradyarrhythmia and circulatory collapse. Mad honey, which comes from plants with grayanotoxin, has various uses, namely, as an aphrodisiac, as an alternative therapy for GI disorders such as peptic ulcer, dyspepsia, and gastritis, and as a treatment for hypertension. However, GI, neurological and cardiac side effects may arise from its ingestion due to the grayanotoxin contained by this type of honey. Cardiac rhythm disturbances, sinus bradycardia, and other life-threatening side effects can occur, especially atrioventricular (AV) block and nodal rhythms. In this article, we present five honey poisoning cases involving adults who were admitted to our ED. Notably, one of the patients was unresponsive to atropine, so a temporary pacemaker was inserted, after which the patient was moved to the coronary ICU. Meanwhile, the cardiac rhythm of the other cases returned to normal in the follow-up after atropine administration.

12.
Environ Monit Assess ; 193(6): 357, 2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-34032942

RESUMEN

In this study, the basal area increment models were developed to be both age dependent and independent with a stepwise multiple regression analysis for coppice-originated pure sessile oak stands in the Marmara region, which is located in north-western Turkey. Data was obtained from a total of 73 sample trees, which were sampled from coppice-originated pure sessile oak stands over different growth periods and in different site conditions. The most suitable competition variable was determined by examining the correlations between the 24 competition index values and calculated using different approaches and the basal area increment. The individual tree basal area increment models were obtained as functions of tree size, competition, age, and site characteristics. The most important variables that affect the basal area increment in the age-dependent model were the diameter at breast height (DBH) (36.1%), competition index (26.4%), and age (10%). For the age-independent model, the variables are the competition index (32.6%), DBH (30.3%), and the site index (3%), according to the relative importance values. The age-dependent model explained the increased variation of 10% and predicted a 13% decrease in error in the basal area increment than the age-independent model.


Asunto(s)
Quercus , Monitoreo del Ambiente , Árboles , Turquía
13.
BMC Cardiovasc Disord ; 21(1): 224, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33932981

RESUMEN

BACKGROUND: Venous thromboembolism clinically presenting with a deep vein thrombosis or pulmonary embolism is among the most commonly seen cardiovascular syndromes. The aim of this case presentation is to emphasise the typical electrocardiographic findings that are detected with massive pulmonary embolism along with the electrocardiographic S1Q3 and S1Q3T3 accompanied by T negativity at the D3 derivation based on prevalent T negativity. CASE PRESENTATION: We present the case of an adult male who presented with a massive pulmonary embolism that was associated with tachycardia, haemoptysis and typical S1Q3T3 electrocardiographic findings. Tomographic findings showed filling defects in the two main pulmonary artery lumens, which were found to be compatible with a massive embolism. Intravenous heparin was injected (5000 IU), and low molecule weight heparin (LMWH) treatment was initiated. After two days of observation and treatment in the coronary intensive care unit, the patient was discharged for outpatient care. DISCUSSION: Massive pulmonary embolism is an urgent life-threatening clinical situation that is frequently confused with acute ST elevation myocardial infarction. The definitive diagnosis of massive pulmonary embolism was made with a computed tomography pulmonary angiogram. Electrocardiographic findings and hypoxic hypercarbia in the blood gas analysis are typical. Early diagnosis with laboratory and imaging investigations is vital in the treatment and prognosis of pulmonary embolism. CONCLUSIONS: Ventricular overload signs accompanied by ST segment elevation in electrocardiography and S1Q3 and prevalent T negativity are crucial features in terms of distinguishing between pulmonary embolism and myocardial infarction and selecting effective treatments for patients admitted to the emergency department.


Asunto(s)
Electrocardiografía , Hemoptisis/etiología , Infarto del Miocardio/diagnóstico , Embolia Pulmonar/diagnóstico , Anticoagulantes/administración & dosificación , Toma de Decisiones Clínicas , Angiografía por Tomografía Computarizada , Diagnóstico Diferencial , Heparina/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Embolia Pulmonar/complicaciones , Embolia Pulmonar/tratamiento farmacológico , Resultado del Tratamiento
14.
Environ Monit Assess ; 193(2): 83, 2021 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-33495913

RESUMEN

Pollarding of oak trees for livestock and animal feeding is a traditional application, and it has been used for centuries from generation to generation in southern and southeastern Turkey. Estimation of the fresh sprout biomass (FSB) potential of pollarded oak forests in high accuracy is important for sustainable forest management. In the present study, 40 trees were sampled from Turkey oak (Quercus cerris L.) stands that have been irregularly pollarded for animal husbandry in Adiyaman, southeastern Turkey. In order to estimate FSB, a multiple logarithmic linear model was developed with explanatory variables such as tree diameter at breast height (DBH), total tree height (H), mean sprout length (SL), and mean sprout age (SA), which are in a significant relationship with FSB. Stepwise multiple regression analysis was used to fit this multiple logarithmic linear model and to determine the best independent variable set. As a result of stepwise regression analysis, three models were obtained in which SL, DBH, and SA are independent variables. Model 1 estimates the FSB by taking only SL, Model 2 uses SL and DBH, and Model 3 uses SL, DBH, and SA as independent variables. All models were significant at p = 0.001 level. Model 1 explained the variation in FSB by 65%, Model 2 by 81%, and Model 3 by 86%. Inclusion of DBH in the model (Model 2) decreased the mean absolute error (MAE) of FSB by 26% and the inclusion of SA (Model 3) decreased MAE by 43%.


Asunto(s)
Quercus , Árboles , Biomasa , Monitoreo del Ambiente , Bosques , Turquía
15.
Environ Monit Assess ; 192(7): 418, 2020 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-32506188

RESUMEN

Biomass equations were developed for different components of oak trees (Quercus cerris L.), which have been managed in coppices at different development stages-small-diameter forest (SDF) and medium-diameter forest (MDF). In this context, four biomass regression models-two based on diameter at breast height (DBH) alone and two based on DBH and total tree height (H)-were developed for each of the crown, stem, and total aboveground biomass components. Akaike's information criterion (AIC), root mean square error percentage (RMSE (%)), mean absolute error percentage (MAE (%)), adjusted coefficient of determination (Adj.R2), and bias values were used to evaluate and compare the suitability of a total of 12 regression models developed for biomass components. As a result, in the estimation of crown biomass, only DBH-based models provided higher estimation accuracy than DBH-H-based models. For the most suitable model, estimated values were Adj.R2 = 0.60, bias = - 0.009, RMSE = 66%, and MAE = 41%. In models developed to estimate stem biomass, the estimation accuracy of DBH-H-based models was higher. In the goodness-of-fit statistics calculated for the most suitable model, Adj.R2, bias, RMSE, and MAE were 0.89, 0.010, 38%, and 23%, respectively. The models developed to estimate the total aboveground biomass were all close in terms of estimation accuracy. The biomass components (crown and stem) in the total aboveground biomass were proportionally as follows: crown at 38% and stem at 62% in the SDF stage, and crown at 35% and stem at 65% in the MDF stage, indicating lower crown and higher stem partitioning as the development stage increased.


Asunto(s)
Biomasa , Monitoreo del Ambiente , Modelos Teóricos , Componentes Aéreos de las Plantas , Quercus , Análisis de Regresión , Turquía
16.
Environ Monit Assess ; 192(6): 363, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32405707

RESUMEN

The biomass, carbon and nitrogen storage in the single tree components (foliage, branch, crown, bark, stem and total aboveground) of the grey poplar (Populus × canescens) in its distribution in Eastern Anatolia (Van, Turkey) were determined and modelled. The biomass, carbon and nitrogen storages were not estimated at a stand level but were based on single trees. Regression models based on the tree diameter at breast height (DBH) and total tree height (H) were developed to estimate the biomass, carbon (C) storage and nitrogen (N) storage of the different tree components of a total of 28 grey poplar trees. The two main regression models in the power function were developed based only on the DBH (Model 1) and the combination of the DBH and height (D2H) (Model 2). All regression models, except for those of the foliage components, developed to estimate the biomass and C and N storages of the tree components were found to be statistically significant (p < 0.001). The partitioning of the total aboveground biomass in the bark, foliage, branches and stems was 0.7, 9, 17 and 73%, respectively. The average C concentrations of the tree components ranged from 48 (foliage) to 50% (bark, branch and stem), while the N concentrations ranged from 0.35 (stem) to 1.32% (foliage). Higher biomass and lower nitrogen concentrations of foliage compared with cultivated poplars were likely related to the natural site conditions, low soil nitrogen and/or characteristics of single tree growth.


Asunto(s)
Monitoreo del Ambiente , Populus , Árboles , Biomasa , Carbono , Ecosistema , Nitrógeno , Turquía
18.
J Coll Physicians Surg Pak ; 29(11): 1038-1042, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31659958

RESUMEN

OBJECTIVE: To compare surgical risk scores including Euroscore II, STS and Logistic Euroscore for their predictive ability about postoperative atrial fibrillation (POAF). STUDY DESIGN: Prospective cohort study. PLACE AND DURATION OF STUDY: Istanbul Yeni Yuzyil University, Gaziosmanpasa Hospital and Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Center, from June to December 2018. METHODOLOGY: One hundred and four patients, undergoing isolated coronary artery bypass grafting operation, were enrolled. Surgical risk scores, clinical, laboratory and echocardiographic parameters were compared between POAF-positive and POAF-negative groups Results: Of the 104 patients included, 23 (22.1%) patients developed atrial fibrillation postoperatively. Peripheral artery disease, carotid artery disease, current smoking, cardiopulmonary bypass time, left atrial diameter, and Syntax II score were found to be associated with POAF. Among these, peripheral artery disease and cardiopulmonary bypass time were independently related with POAF. Euroscore II (p = 0.005), STS (p = 0.026) and Logistic Euroscore (p = 0.032) were all statistically higher in POAF developing patients. In terms of ROC analysis, area under the curve was higher in Euroscore II (0.697) than STS and Logistic Euroscore (0.658 and 0.652, respectively). CONCLUSION: Euroscore II, STS and Logistic Euroscore were all associated with POAF development. However, Euroscore II could be a better option for the prediction of POAF.


Asunto(s)
Fibrilación Atrial/epidemiología , Puente de Arteria Coronaria , Complicaciones Posoperatorias/epidemiología , Medición de Riesgo , Angiografía Coronaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Turquía/epidemiología
19.
Rev Port Cardiol (Engl Ed) ; 38(6): 419-423, 2019 Jun.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-31324408

RESUMEN

INTRODUCTION: Imbalance between pro- and anti-inflammatory cytokines secreted from visceral adipose tissue (VAT) contributes to the pathogenesis of certain cardiovascular and metabolic disorders, including insulin resistance. Epicardial adipose tissue (EAT) is a form of VAT mainly concentrated along the coronary arteries. It has been shown in various studies that EAT thickness is positively correlated with cardiovascular disease. Due to its high worldwide prevalence, prevention and management of type 2 diabetes (T2D) has become a major public health challenge. Metformin, the most widely prescribed drug to treat T2D, has favorable effects on VAT and body weight. As metformin decreases VAT mass, in this prospective study we analyzed the possible positive effect of metformin on EAT mass, which is organ-specific VAT, and body mass index (BMI). METHODS: Subjects were selected from patients admitted to the internal medicine outpatient clinic. Newly diagnosed T2D patients treated with metformin monotherapy were analyzed and 40 patients were included. EAT thickness in the included patients was measured echocardiographically. BMI and EAT thickness were analyzed at the beginning (BMI0 and EAT0) and after three months of metformin monotherapy (BMI3 and EAT3). RESULTS: There was a statistically significant decrease in EAT thickness after three months of metformin monotherapy (EAT0=5.07±1.33 mm vs. EAT3=4.76±1.32 mm; p<0.001). Furthermore, BMI was also significantly decreased (BMI0=28.27±2.71 vs. BMI3=27.29±2.10; p<0.0001). CONCLUSIONS: In this study we show that metformin monotherapy significantly decreases EAT thickness and BMI in T2D patients. This suggests that metformin could reduce the frequency of coronary atherosclerosis.


Asunto(s)
Tejido Adiposo/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/etiología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Metformina/uso terapéutico , Pericardio/diagnóstico por imagen , Índice de Masa Corporal , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/prevención & control , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Ecocardiografía Doppler , Femenino , Estudios de Seguimiento , Humanos , Hipoglucemiantes/uso terapéutico , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
20.
Environ Monit Assess ; 191(7): 466, 2019 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-31243561

RESUMEN

High levels of atmospheric pollutants have been frequently measured in Turkey during the last decade. Specifically, the occurrence of these high particulate matter concentrations is often related to either local-scale conditions or regional-scale transport. In order to better understand the atmospheric factors that trigger poor air quality, further research investigating the relationship between air pollution and meteorological variables or atmospheric circulation patterns is needed. In this study, the influence of synoptic-scale weather types on PM10 levels over the Aegean region of Turkey is investigated for the period 2008-2015. First of all, hourly PM10 concentrations of 13 air quality stations are respectively converted to daily, seasonal, and regional averages. The seasonal variability of PM10 values in the region indicates that high particulate matter concentrations are registered in winter, fall, spring, and summer months with mean values at 90.6 (± 38.3 standard deviation), 66.9 (± 28.3), 61.6 (± 23.4), and 54.1 (± 12.8) µg m-3, respectively. In regard to the synoptic-scale approach, eight directional and two vorticity types of the Lamb weather type (LWT) method are used in the analysis. Based on the results, poor air quality conditions are observed in all seasons during active southeasterly (SE, interaction between a low pressure over Italy and a high pressure over the Caspian Sea) circulation types (CTs). In winter, mainly easterly (E), SE, southerly (S), and anticyclonic (A) weather patterns result in above normal PM10 concentrations. In addition to these four CTs, southwesterly (SW) types also cause higher PM10 values in the spring season. During summer, SE, SW, westerly (W), and cyclonic (C) CTs are associated with above-normal PM10 values. During fall, obvious higher PM10 concentrations are found during SE, S, and A types.


Asunto(s)
Movimientos del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Estaciones del Año , Turquía
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