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1.
J Fluoresc ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457077

RESUMO

Tb(III)-2-aminoterphthalate complex Tb2-(ATPh)3 was synthesized and characterized using FT-IR, thermal analysis and elemental analysis. Tb2(ATPh)3 microtiter plate was fabricated through embedding Tb(III) complex in polyvinyl chloride membrane and used for environmental determination of phenol in sea water samples. The calculated detection (DL), quantification (QL) limits, and binding constant (KD) were 00.63 µmol L- 1, 2.10 µmol L- 1 and 1.32 × 104 mol- 1 L, respectively. The fabricated microtiter plates exhibited high selectivity towards phenol over other hydrocarbon compounds. Furthermore, AGREE metric tool was used to assess the method's green nature as well as its practicability and applicability. These merit outcomes provide that the new method for phenol detection was environmentally benign and safe to humans. The prepared Tb2(ATPh)3 MTP was validated through using gas chromatography for monitoring phenol in Suez Bay water accurately with high precision. The obtained results encouraged using Tb2(ATPh)3 MTP for efficient, fast, selective, and direct screening of phenol in real samples.

2.
J Fluoresc ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958904

RESUMO

A new eco-friendly sensor, 3-((6-((4-chlorobenzylidene)amino)pyridin-2-yl)imino)indolin-2-one (CBAPI) was synthesized and well characterized. The CBAPI sensor was employed for detecting Zn2+ and Fe3+ ions. It exhibited a low limit of detection at pH 6.0, with values of 2.90, for Zn2+ and 3.59 nmol L-1 for Fe3+ ions. The sensor demonstrated high selectivity over other interfering cations. Additionally, the high binding constants reflect the great affinity of sensor towards Zn2+ and Fe3+ ions. To further validate its quantification ability for Zn2+ ions, the synthesized CBAPI sensor was used to determine Zn levels in human hair samples, and the results were confirmed using atomic absorption spectroscopy (AAS). The AGREE metric tool was used to assess the method's environmental impact and practical applicability. These positive outcomes indicated that the new method for detecting Zn2+ and Fe3+ ions is environmentally friendly and safe for humans. The developed CBAPI sensor represents a potential development in metal ion detection, combining sensitivity, selectivity, and rapidity.

3.
Environ Monit Assess ; 195(6): 693, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37204517

RESUMO

In the present era of significant industrial development, the presence and dispersal of countless water contaminants in water bodies worldwide have rendered them unsuitable for various forms of life. Recently, the awareness of environmental sustainability for wastewater treatment has increased rapidly in quest of meeting the global water demand. Despite numerous conventional adsorbents on deck, exploring low-cost and efficient adsorbents is interesting. Clays and clays-based geopolymers are intensively used as natural, alternative, and promising adsorbents to meet the goals for combating climate change and providing low carbon, heat, and power. In this narrative work, the present review highlights the persistence of some inorganic/organic water pollutants in aquatic bodies. Moreover, it comprehensively summarizes the advancement in the strategies associated with synthesizing clays and their based geopolymers, characterization techniques, and applications in water treatment. Furthermore, the critical challenges, opportunities, and future prospective regarding the circular economy are additionally outlined. This review expounded on the ongoing research studies for leveraging these eco-friendly materials to address water decontamination. The adsorption mechanisms of clays-based geopolymers are successfully presented. Therefore, the present review is believed to deepen insights into wastewater treatment using clays and clays-based geopolymers as a groundbreaking aspect in accord with the waste-to-wealth concept toward broader sustainable development goals.


Assuntos
Poluentes Químicos da Água , Poluentes da Água , Purificação da Água , Águas Residuárias , Argila , Monitoramento Ambiental , Adsorção , Purificação da Água/métodos
4.
Am J Obstet Gynecol ; 226(1): 112.e1-112.e10, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34389293

RESUMO

BACKGROUND: Determining fetal head descent, expressed as fetal head station and engagement is an essential part of monitoring progression in labor. Assessing fetal head station is based on the distal part of the fetal skull, whereas assessing engagement is based on the proximal part. Prerequisites for assisted vaginal birth are that the fetal head should be engaged and its lowermost part at or below the level of the ischial spines. The part of the fetal head above the pelvic inlet reflects the true descent of the largest diameter of the skull. In molded (reshaped) fetal heads, the leading bony part of the skull may be below the ischial spines while the largest diameter of the fetal skull still remains above the pelvic inlet. An attempt at assisted vaginal birth in such a situation would be associated with risks. Therefore, the vaginal or transperineal assessments of station should be supplemented with a transabdominal examination. We suggest a method for the assessment of fetal head descent with transabdominal ultrasound. OBJECTIVE: To investigate the correlation between transabdominal and transperineal assessment of fetal head descent, and to study fetal head shape at different labor stages and head positions. STUDY DESIGN: Women with term singleton cephalic pregnancies admitted to the labor ward for induction of labor or in spontaneous labor, at the Cairo University Hospital and Oslo University Hospital from December 2019 to December 2020 were included. Fetal head descent was assessed with transabdominal ultrasound as the suprapubic descent angle between a longitudinal line through the symphysis pubis and a line from the upper part of the symphysis pubis extending tangentially to the fetal skull. We compared measurements with transperineally assessed angle of progression and investigated interobserver agreement. We also measured the part of fetal head above and below the symphysis pubis at different labor stages. RESULTS: The study population comprised 123 women, of whom 19 (15%) were examined before induction of labor, 8 (7%) in the latent phase, 52 (42%) in the active first stage and 44 (36%) in the second stage. The suprapubic descent angle and the angle of progression could be measured in all cases. The correlation between the transabdominal and transperineal measurements was -0.90 (95% confidence interval, -0.86 to -0.93). Interobserver agreement was examined in 30 women and the intraclass correlation coefficient was 0.98 (95% confidence interval, 0.95-0.99). The limits of agreement were from -9.5 to 7.8 degrees. The fetal head was more elongated in occiput posterior position than in non-occiput posterior positions in the second stage of labor. CONCLUSION: We present a novel method of examining fetal head descent by assessing the proximal part of the fetal skull with transabdominal ultrasound. The correlation with transperineal ultrasound measurements was strong, especially early in labor. The fetal head was elongated in the occiput posterior position during the second stage of labor.


Assuntos
Feto/diagnóstico por imagem , Cabeça/diagnóstico por imagem , Apresentação no Trabalho de Parto , Primeira Fase do Trabalho de Parto , Segunda Fase do Trabalho de Parto , Ultrassonografia Pré-Natal , Adulto , Feminino , Humanos , Gravidez
5.
BMC Pregnancy Childbirth ; 22(1): 650, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35982412

RESUMO

BACKGROUND: At present, the prevalence of pregestational diabetes is 2.2% with an overall prevalence of hyperglycaemia in pregnancy of about 16.2%. Fetuses of diabetic mothers are at risk of functional cardiac abnormalities without structural cardiac anomalies especially in the third trimester. The main aim of this study was to assess the association of diabetes with different fetal echocardiographic parameters. METHODS: A case control study comprising a total of 120 pregnant women (60 cases and 60 controls). The cases group included fetuses of mothers known to have pre-gestational type 2 diabetes (DM group) while the control group included fetuses of euglycaemic healthy pregnant women. They were examined twice at 23-24 weeks' gestation (visit 1) and followed up at 27-28 weeks' gestation (visit 2). The Modified Myocardial Performance Index (Mod MPI) was obtained in all fetuses. Also, M-mode echocardiography was used to measure the interventricular septum thickness at diastole in a transverse four chamber view. RESULTS: There was a significant increase in Iso-volumetric contraction time (ICT) (45.4 ms ± 8.9), Iso-volumetric relaxation time (IRT) (54.7 ms ± 11.22), Interventricular septal thickness (IVST) (4.08 mm ± 0.8), aortic acceleration time (AAT) (54.16 ms ± 12.77) and MPI (0.64 ± 0.09) in the diabetic group compared to the normal control group ICT (38.5 ms ± 9.59), IRT (46.13 ms ± 10.29), IVST (3.17 mm ± 0.6), AAT (49.73 ms ± 10.68) and MPI (0.5 ± 0.1) (all P values were < 0.001). When comparing parameters assessed at both visits among diabetic patients, there was a significant increase in IVST in the second visit (4.74 ± 0.78 mm) compared to the first visit (4.08 ± 0.8 mm) (P value < 0.05). The incidence of hypertrophic cardiomyopathy (HCM) was significantly higher in diabetic patients than in the control group. This is was observed in both first and second visit (33.4% and 56.7%) (P value < 0.001). CONCLUSIONS: Fetuses of diabetic pregnant females show a significant increase in MPI, decrease in E\A ratio and HCM. These alterations in cardiac functions and structure were found to be continuous throughout the period of time between the two visits.


Assuntos
Diabetes Mellitus Tipo 2 , Coração Fetal , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Ecocardiografia , Feminino , Coração Fetal/diagnóstico por imagem , Idade Gestacional , Humanos , Gravidez , Ultrassonografia Pré-Natal
6.
J Perinat Med ; 50(8): 1007-1029, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-35618672

RESUMO

This recommendation document follows the mission of the World Association of Perinatal Medicine in collaboration with the Perinatal Medicine Foundation. We aim to bring together groups and individuals throughout the world for standardization to implement the ultrasound evaluation in labor ward and improve the clinical management of labor. Ultrasound in labor can be performed using a transabdominal or a transperineal approach depending upon which parameters are being assessed. During transabdominal imaging, fetal anatomy, presentation, liquor volume, and placental localization can be determined. The transperineal images depict images of the fetal head in which calculations to determine a proposed fetal head station can be made.


Assuntos
Parto Obstétrico , Apresentação no Trabalho de Parto , Parto Obstétrico/métodos , Feminino , Cabeça/diagnóstico por imagem , Humanos , Placenta , Gravidez , Estudos Prospectivos , Ultrassonografia Pré-Natal/métodos
7.
Am J Obstet Gynecol ; 224(6): 609.e1-609.e11, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33412128

RESUMO

BACKGROUND: Induction of labor is one of the most common interventions in modern obstetrics, and its frequency is expected to continue to increase. There is inconsistency as to how failed induction of labor is defined; however, the majority of studies define success as the achievement of vaginal delivery. Induction of labor in nulliparous women poses an additional challenge with a 15% to 20% incidence of failure, ending in emergency operative deliveries. The Bishop score has been traditionally used before decisions for induction of labor. Nonetheless, it is subjective and prone to marked interobserver variation. Several studies have been conducted to find alternative predictors, yet a reliable, objective method still remains to be introduced and validated. Hence, there is still a need for the development of new predictive tools to facilitate informed decision making, optimization of resources, and minimization of potential risks of failure. Furthermore, a peripartum transperineal ultrasound scan has been proven to provide objective, noninvasive assessment of labor. OBJECTIVE: This study aimed to assess the feasibility of developing and validating an objective and reproducible model for the prediction of cesarean delivery for failure to progress as an outcome of labor induction in term singleton pregnancies. STUDY DESIGN: This was a prospective observational cohort study conducted in Cairo University Hospitals and University of Bologna Hospitals between November 2018 and November 2019. We recruited 382 primigravidae with singleton term pregnancies in cephalic presentation. All patients had baseline Bishop scoring together with various transabdominal and transperineal ultrasound assessments of the fetus, maternal cervix, and pelvic floor. The managing obstetricians were blinded to the ultrasound scan findings. The method and indication of induction of labor, the total duration of stages of labor, mode of birth, and neonatal outcomes were all recorded. Women who had operative delivery for fetal distress or indications other than failure to progress in labor were excluded from the final analysis, leaving a total of 344 participants who were randomly divided into 243 and 101 pregnancies that constituted the model development and cross-validation groups, respectively. RESULTS: It was possible to perform transabdominal and transperineal scans and assess all the required parameters on all study participants. Univariate and multivariate analyses were used for selection of potential predictors and model fitting. The independent predictive variables for cesarean delivery included maternal age (odds ratio, 1.12; P=.003), cervical length (odds ratio, 1.08; P=.04), angle of progression at rest (odds ratio, 0.9; P=.001), and occiput posterior position (odds ratio, 5.7; P=.006). We tested the performance of the prediction model on our cross-validation group. The calculated areas under the curve for the ability of the model to predict cesarean delivery were 0.7969 (95% confidence interval, 0.71-0.87) and 0.88 (95% confidence interval, 0.79-0.97) for the developed and validated models, respectively. CONCLUSION: Maternal age and sonographic fetal occiput position, angle of progression at rest, and cervical length before labor induction are very good predictors of induction outcome in nulliparous women at term.


Assuntos
Cesárea/estatística & dados numéricos , Regras de Decisão Clínica , Trabalho de Parto Induzido , Complicações do Trabalho de Parto/terapia , Adolescente , Adulto , Feminino , Humanos , Modelos Estatísticos , Complicações do Trabalho de Parto/diagnóstico por imagem , Complicações do Trabalho de Parto/etiologia , Gravidez , Estudos Prospectivos , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Método Simples-Cego , Falha de Tratamento , Ultrassonografia Pré-Natal/métodos , Adulto Jovem
8.
Am J Obstet Gynecol ; 225(1): 81.e1-81.e9, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33508312

RESUMO

BACKGROUND: Occiput posterior position is the most frequent cephalic malposition, and its persistence at delivery is associated with a higher risk of maternal and perinatal morbidity. Diagnosis and management of occiput posterior position remain a clinical challenge. This is partly caused by our inability to predict fetuses who will spontaneously rotate into occiput anterior from those who will have persistent occiput posterior position. The angle of progression, measured with transperineal ultrasound, represents a reliable tool for the evaluation of fetal head station during labor. The relationship between the persistence of occiput posterior position and fetal head station in the second stage of labor has not been previously assessed. OBJECTIVE: This study aimed to evaluate the role of fetal head station, as measured by the angle of progression, in the prediction of persistent occiput posterior position and the mode of delivery in the second stage of labor. STUDY DESIGN: We recruited a nonconsecutive series of women with posterior occiput position diagnosed by transabdominal ultrasound in the second stage of labor. For each woman, a transperineal ultrasound was performed to measure the angle of progression at rest. We compared the angle of progression between women who delivered fetuses in occiput anterior position and those with persistent occiput posterior position at delivery. Receiver operating characteristics curves were performed to evaluate the accuracy of the angle of progression in the prediction of persistent occiput posterior position. Finally, we performed a multivariate logistic regression to determine independent predictors of persistent occiput posterior position. RESULTS: Overall, 63 women were included in the analysis. Among these, 39 women (62%) delivered in occiput anterior position, whereas 24 (38%) delivered in occiput posterior position (persistent occiput posterior position). The angle of progression was significantly narrower in the persistent occiput posterior position group than in women who delivered fetuses in occiput anterior position (118.3°±12.2° vs 127.5°±10.5°; P=.003). The area under the receiver operating characteristics curve was 0.731 (95% confidence interval, 0.594-0.869) with an estimated best cutoff range of 121.5° (sensitivity of 72% and specificity of 67%). On logistic regression analysis, the angle of progression was found to be independently associated with persistence of occiput posterior position (odds ratio, 0.942; 95% confidence interval, 0.889-0.998; P=.04). Finally, women who underwent cesarean delivery had significantly narrower angle of progression than women who had a vaginal delivery (113.5°±8.1 vs 128.0°±10.7; P<.001). The area under the receiver operating characteristics curve for the prediction of cesarean delivery was 0.866 (95% confidence interval, 0.761-0.972). At multivariable logistic regression analysis including the angle of progression, parity, and gestational age at delivery, the angle of progression was found to be the only independent predictor associated with cesarean delivery (odds ratio, 0.849; 95% confidence interval, 0.775-0.0930; P<.001). CONCLUSION: In fetuses with occiput posterior at the beginning of the second stage of labor, narrower values of the angle of progression are associated with higher rates of persistent occiput posterior position at delivery and a higher risk of cesarean delivery.


Assuntos
Parto Obstétrico/métodos , Apresentação no Trabalho de Parto , Segunda Fase do Trabalho de Parto/fisiologia , Ultrassonografia Pré-Natal/métodos , Adulto , Cesárea/estatística & dados numéricos , Feminino , Feto/diagnóstico por imagem , Idade Gestacional , Humanos , Paridade , Gravidez , Estudos Prospectivos , Curva ROC
9.
Am J Obstet Gynecol ; 220(2): 189.e1-189.e8, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30321525

RESUMO

BACKGROUND: The Valsalva maneuver is normally accompanied by relaxation of the levator ani muscle, which stretches around the presenting part, but in some women the maneuver is accompanied by levator ani muscle contraction, which is referred to as levator ani muscle coactivation. The effect of such coactivation on labor outcome in women undergoing induction of labor has not been previously assessed. OBJECTIVE: The aim of the study was to assess the effect of levator ani muscle coactivation on labor outcome, in particular on the duration of the second and active second stage of labor, in nulliparous women undergoing induction of labor. STUDY DESIGN: Transperineal ultrasound was used to measure the anteroposterior diameter of the levator hiatus, both at rest and at maximum Valsalva maneuver, in a group of nulliparous women undergoing induction of labor in 2 tertiary-level university hospitals. The correlation between anteroposterior diameter of the levator hiatus values and levator ani muscle coactivation with the mode of delivery and various labor durations was assessed. RESULTS: In total, 138 women were included in the analysis. Larger anteroposterior diameter of the levator hiatus at Valsalva was associated with a shorter second stage (r = -0.230, P = .021) and active second stage (r = -0.338, P = .001) of labor. Women with levator ani muscle coactivation had a significantly longer active second stage duration (60 ± 56 vs 28 ± 16 minutes, P < .001). Cox regression analysis, adjusted for maternal age and epidural analgesia, demonstrated an independent significant correlation between levator ani muscle coactivation and a longer active second stage of labor (hazard ratio, 2.085; 95% confidence interval, 1.158-3.752; P = .014). There was no significant difference between women who underwent operative delivery (n = 46) when compared with the spontaneous vaginal delivery group (n = 92) as regards anteroposterior diameter of the levator hiatus at rest and at Valsalva maneuver, nor in the prevalence of levator ani muscle coactivation (10/46 vs 15/92; P = .49). CONCLUSION: Levator ani coactivation is associated with a longer active second stage of labor.


Assuntos
Segunda Fase do Trabalho de Parto/fisiologia , Trabalho de Parto Induzido , Contração Muscular/fisiologia , Diafragma da Pelve/fisiopatologia , Manobra de Valsalva/fisiologia , Adulto , Feminino , Humanos , Paridade , Diafragma da Pelve/diagnóstico por imagem , Períneo/diagnóstico por imagem , Gravidez , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Tempo , Ultrassonografia
10.
Int J Biol Macromol ; 248: 125986, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37506792

RESUMO

Chitosan/aspartic acid hydrogels were synthesized for MB dye removal from textile aqueous effluents with different ratios by gelation of chitosan with non-toxic gelling agent, crosslinker, glutaraldehyde (Glu). The obtained hydrogels were characterized by spectral and morphological techniques. The characterization techniques confirmed successful preparations and MB dye adsorption. Batch experiments were done to investigate the effects of adsorbent dose, pH, contact time, temperature, and initial MB dye concentration. The optimum conditions were: adsorbent dose 0.1 g, pH 5, contact time 30 min, and temperature 25 °C for Chitosan-Aspartic Acid Hydrogel 1 (CSAA-HG1) and adsorbent dose 0.4 g, pH 2, contact time 60 min, temperature 25 °C for Chitosan-Aspartic Acid Hydrogel 2 (CSAA-HG2). Adsorption capacity of newly hydrogels CSAA-HG1,2 was compared with each other. Adsorption efficiencies reached 99.85 % for CSAA-HG1 and 99.88 % for CSAA-HG2. MB dye adsorption on CSAA-HG1,2 followed Freundlich isotherm model (R2 = 0.94 and 0.92, respectively). Both adsorbents exhibited pseudo-second-order kinetics for MB dye adsorption (R2 = 1). The negative ΔHo indicated that the MB dye adsorption was exothermic, negative ΔGo confirmed that MB dye adsorption process was spontaneous and low values of ∆So indicated low degree of freedom, ordered MB dye molecules on CSAA-HG1,2 surfaces.


Assuntos
Quitosana , Poluentes Químicos da Água , Azul de Metileno/química , Quitosana/química , Ácido Aspártico , Hidrogéis/química , Análise Custo-Benefício , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Adsorção , Cinética , Corantes/química , Termodinâmica
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 288: 122203, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36477004

RESUMO

For the analytical determination of Fe(II) and Pd(II) concentrations, a novel optical sensor based on spectrophotometric technique was used. The optical sensor was prepared by direct immobilization of a novel synthesized chromophore, 5-amino-phenanthrolin-3 formyl salicylic acid, onto nanocellulose. Human vision can identify the color associated with Fe II ions, and spectrophotometric methods can measure it with detection and quantification limits of 0.239 and 0.796 ppb, respectively. Pd(II) detection and quantification limits were 0.318 ppb and 1.06 ppb, respectively. The effects of various parameters on the detection of Fe(II) or Pd(II) ion content were investigated and optimized. The optical phenanthroline-nanocellulose (5-Phen) sensor could be reproduced multiple times and used with a higher capacity each time. The results demonstrated that the 5-Phen sensor could measure Fe(II) in human blood serum accurately and successfully even without any pre-concentration.


Assuntos
Compostos Ferrosos , Ácido Salicílico , Humanos , Espectrofotometria , Íons
12.
Bioengineering (Basel) ; 10(7)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37508782

RESUMO

The dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) technique has taken on a significant and increasing role in diagnostic procedures and treatments for patients who suffer from chronic kidney disease. Careful segmentation of kidneys from DCE-MRI scans is an essential early step towards the evaluation of kidney function. Recently, deep convolutional neural networks have increased in popularity in medical image segmentation. To this end, in this paper, we propose a new and fully automated two-phase approach that integrates convolutional neural networks and level set methods to delimit kidneys in DCE-MRI scans. We first develop two convolutional neural networks that rely on the U-Net structure (UNT) to predict a kidney probability map for DCE-MRI scans. Then, to leverage the segmentation performance, the pixel-wise kidney probability map predicted from the deep model is exploited with the shape prior information in a level set method to guide the contour evolution towards the target kidney. Real DCE-MRI datasets of 45 subjects are used for training, validating, and testing the proposed approach. The valuation results demonstrate the high performance of the two-phase approach, achieving a Dice similarity coefficient of 0.95 ± 0.02 and intersection over union of 0.91 ± 0.03, and 1.54 ± 1.6 considering a 95% Hausdorff distance. Our intensive experiments confirm the potential and effectiveness of that approach over both UNT models and numerous recent level set-based methods.

13.
J Fluoresc ; 22(3): 971-92, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22302597

RESUMO

The luminescence arising from lanthanide cations offers several advantages over organic fluorescent molecules: sharp, distinctive emission bands allow for easy resolution between multiple lanthanide signals; long emission lifetimes (µs -ms) make them excellent candidates for time-resolved measurements; and high resistance to photo bleaching allow for long or repeated experiments. A method is presented for determination of nucleosides using the effect of enhancement of fluorescence of the easily accessible europium(III)-TNB in presence of different nucleosides. The latter coordinates to Eu(III) -TNB and enhances its luminescence intensity as a result of the displacement of water from the inner coordination sphere of the central metal. A similar method for the determination of DNA based on the quenching of Eu(III)-TNB has been established. The interaction of Eu(III)-4,4,4 trifluoro-1-(2-naphthyl)1,3-butanedione (TNB) complex with nucleosides (NS) (guanosine, adenosine, cytidine, inosine) and DNA has been studied using normal and time-resolved luminescence techniques. Binding constants were determined at 293 K, 298 K, 303 K, 308 K and 313 K by using Benesi-Hildebrand equation. A thermodynamic analysis showed that the reaction is spontaneous with ΔG being negative. The enthalpy ΔH and the entropy ΔS of reactions were all determined. The formation of binary and ternary complexes of Eu(III) with nucleosides and TNB has been studied potentiometrically at (25.0 ± 0.1) °C and ionic strength I = 0.1 mol.dm(-3) (KNO3) . The formation of the 1:1 binary and 1:1:1 ternary complexes are inferred from the corresponding titration curves. Initial estimates of the formation constants of the resulting species and the protonation constants of the different ligands used have been refined with the HYPERQUAD computer program. Electrochemical investigations for the systems under investigations have been carried out using cyclic voltammetry (CV), differential pulse polarography (DPP), and square wave voltammetry (SWV) on a glassy carbon electrode in I = 0.1 mol/L p-toluenesulfonate as supporting electrolyte.


Assuntos
DNA/análise , Diacetil/análogos & derivados , Európio/química , Fluorescência , Corantes Fluorescentes/química , Medições Luminescentes/métodos , Naftalenos/química , Nucleosídeos/análise , Diacetil/química , Eletroquímica , Corantes Fluorescentes/análise , Corantes Fluorescentes/síntese química , Compostos Organometálicos/análise , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Termodinâmica
14.
J Fluoresc ; 22(2): 659-76, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22048983

RESUMO

This work describes the application of time resolved fluorescence in microtiterplates and electrochemical methods on glassy carbon electrode for investigating the interactions of europium-3-carboxycoumarin with pesticides aldicarb, methomyl and prometryne. Stern-volmer studies at different temperatures indicate that static quenching dominates for methomyl, aldicarb and prometryne. By using Lineweaver-Burk equation binding constants were determined at 303 K, 308 K and 313 K. A thermodynamic analysis showed that the reaction is spontaneous with ΔG being negative. The enthalpy ΔH and the entropy ΔS of reactions were all determined. A time-resolved (gated) luminescence-based method for determination of pesticides in microtiterplate format using the long-lived europium-3-carboxycoumarin has been developed. The limit of detection is 4.80, 5.06 and 8.01 µmol L(-1) for methomyl, prometryne and aldicarb, respectively. This is the lowest limit of detection achieved so far for luminescent lanthanide-based probes for pesticides. The interaction of the probe with the pesticides has been investigated using cyclic voltammetry (CV), differential pulse polarography (DPP), square wave voltammetry (SWV) and linear sweep voltammetry (LSV) on a glassy carbon electrode in I = 0.1 mol L(-1) p-toluenesulfonate at 25 °C. The diffusion coefficients of the reduced species are calculated. The main properties of the electrode reaction occurring in a finite diffusion space are the quasireversible maximum and the splitting of the net SWV peak for Eu(III) ions in the ternary complex formed . It was observed that the increase of the cathodic peak currents using LSV is linear with the increase of pesticides concentration in the range 5 × 10(-7) to 1 × 10(-5) mol L(-1). The detection limit (DL) were about 1.01, 2.23 and 1.89 µmol L(-1) for aldicarb, methomyl and prometryne, respectively. In order to assess the analytical applicability of the method, the influence of various potentially interfering species was examined. Influence of interfering species on the recovery of 10 µmol L(-1) pesticides has been investigated.


Assuntos
Aldicarb/química , Complexos de Coordenação/química , Cumarínicos/química , Corantes Fluorescentes/química , Luminescência , Metomil/química , Praguicidas/química , Prometrina/química , Carbono/química , Técnicas Eletroquímicas , Eletrodos
15.
J Minim Invasive Gynecol ; 19(4): 503-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22748955

RESUMO

STUDY OBJECTIVE: To estimate the degree of agreement between 3-dimensional sonohysterography (3D-SHG) and vaginoscopic hysteroscopy (VH) in detection of uterine cavity abnormalities in patients with recurrent implantation failure in in vitro fertilization cycles. DESIGN: Comparative observational cross-sectional study (Canadian Task Force classification II-1). SETTING: Private assisted-conception unit. PATIENTS: One hundred forty-three patients with a history of at least 2 previous implantation failures despite transfer of good quality embryos in assisted-conception cycles. INTERVENTIONS: 3D-SHG was followed by VH. The Cohen κ for interrater agreement was calculated for the level of agreement between the 2 diagnostic procedures. Procedure time in seconds was recorded for both procedures. Patients were asked to rate their degree of discomfort or pain during both procedures using a visual analog scale. MEASUREMENTS AND MAIN RESULTS: There was a substantial degree of concordance between 3D-SHG and VH (κ = 0.77; 95% confidence interval, 0.6-0.84). The median procedure time for 3D-SHG was 296 seconds (range, 231-327 seconds), and for VH was 315 seconds (range, 232-361 seconds), and the difference was statistically significant (p =.02). The visual analog scale pain scores also showed that 3D-SHG, with a median pain score of 2.1 (range, 1-3) was better tolerated than VH, with a median pain score of 2.9 (range, 2-4) (p < .001). CONCLUSION: Our results show that there is a substantial degree of concordance between 3D-SHG and VH in diagnosing uterine cavity anomalies. We also found that 3D-SHG took significantly less time and induced less patient discomfort than did VH. We recommend that 3D-SHG should be the method of first choice for outpatient evaluation of the uterine cavity.


Assuntos
Implantação do Embrião , Histerossalpingografia , Histeroscopia , Doenças Uterinas/diagnóstico , Útero/anormalidades , Útero/diagnóstico por imagem , Adulto , Estudos Transversais , Endossonografia/efeitos adversos , Feminino , Fertilização in vitro , Humanos , Histerossalpingografia/efeitos adversos , Histeroscopia/efeitos adversos , Imageamento Tridimensional , Infertilidade/etiologia , Infertilidade/terapia , Dor/etiologia , Satisfação do Paciente , Estatísticas não Paramétricas , Fatores de Tempo , Falha de Tratamento , Doenças Uterinas/complicações
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 266: 120474, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34689088

RESUMO

A new fluorescent sensing microtiter plate (MTP) was developed for high sensitivity monitoring of anthracene in seawater samples. For this purpose, two ternary complexes of Tb(III) ions with dibenzoylmethane and neocuproine [Tb(DBM)2(MePhen)] or with dibenzoylmethane and bathocuproine [Tb(DBM)2(PhMePhen)] were synthesized. Elemental analysis, energy dispersive X-ray analysis, X-ray diffraction, infrared and ultraviolet-visible emission, and thermal analysis were conducted on the Tb(III) complexes. The limits of detection (DL) were 0.14 and 1.05 µmol L-1 for [Tb(DBM)2(MePhen)] and [Tb(DBM)2(PhMePhen)], respectively. [Tb(DBM)2(PhMePhen)] MTP is embedded in a membrane made of cellulose acetate. The first high-throughput anthracene sensor MTP, based on [Tb(DBM)2(PhMePhen)] sensor showed a linear range, from 0.2 to 20 µmol L-1. [Tb(DBM)2(PhMePhen)] MTP was validated for accurate and precise monitoring of anthracene using gas chromatography. The selectivity of the [Tb(DBM)2(PhMePhen)] MTP toward anthracene was examined. The data indicated that [Tb(DBM)2(PhMePhen)] MTP is suitable for rapid and direct detection of anthracene.


Assuntos
Antracenos , Térbio , Íons , Água do Mar , Difração de Raios X
17.
J Matern Fetal Neonatal Med ; 35(19): 3751-3760, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33115310

RESUMO

INTRODUCTION: Maternal sepsis is a leading cause of maternal and neonatal mortality. Despite the availability of management protocols, there is disparity in case fatality rates for pregnancy-related sepsis compared to other maternity-related complications. The main aim of this systematic review was to assess concordance between international evidence-based guidelines for the prevention and management of childbirth-related bacterial infections. MATERIAL AND METHODS: The PRISMA statement was followed during the conduct and reporting of this review. PubMed was searched electronically from 2009 to November 2019 for clinical guidelines covering the topic of childbirth-related infections and specific searches for relevant guidelines on the websites of the top five international professional bodies most commonly identified by our searches. We did not apply any language restrictions. Guidelines were included if they provided any information about the prevention or management of childbirth-related bacterial infections irrespective of whether the guideline stated a recommendation or not. Two independent reviewers undertook study selection, decisions about inclusion of selected guidelines and data extraction. Extracted information was synthesized under the following topics: Asymptomatic bacteriuria; group B streptococcal infection (GBS); preterm premature rupture of membranes (P-PROM); intrauterine infection; procedures; maternal sepsis; miscellaneous. Concordance was defined as absence of contradictory information between the different guidelines with regards to a specific topic, subtopic or recommendation. Quality of included guidelines was assessed against the AGREE II guideline reporting domains. RESULTS: A total of 43 guidelines were selected of which 11 were excluded leaving 32 guidelines that fulfilled our inclusion criteria. None of the guidelines fulfilled all the quality assessment domains and 11 (34%) of the guidelines satisfied 1-2 of domains only. Two guidelines covered the topic of asymptomatic bacteriuria, nine for GBS, five for P-PROM and three covered each of intra-amniotic infections maternal sepsis, obstetric procedures and interventions topics. The remaining guidelines covered miscellaneous topics. CONCLUSIONS: There was concordance between guidelines with regards to several aspects in the prophylaxis and treatment of bacteriological infections in pregnancy. Nevertheless, there were several areas of discordance, some of which reached the extent of contradictory information as in the case of antenatal screening for GBS.


Assuntos
Bacteriúria , Ruptura Prematura de Membranas Fetais , Complicações Infecciosas na Gravidez , Infecções Estreptocócicas , Antibioticoprofilaxia , Bacteriúria/complicações , Feminino , Ruptura Prematura de Membranas Fetais/microbiologia , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/prevenção & controle , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/prevenção & controle , Streptococcus agalactiae
18.
Bioengineering (Basel) ; 9(11)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36354565

RESUMO

The segmentation of dynamic contrast-enhanced magnetic resonance images (DCE-MRI) of the kidney is a fundamental step in the early and noninvasive detection of acute renal allograft rejection. In this paper, a new and accurate DCE­MRI kidney segmentation method is proposed. In this method, fuzzy c-means (FCM) clustering is embedded into a level set method, with the fuzzy memberships being iteratively updated during the level set contour evolution. Moreover, population­based shape (PB-shape) and subject-specific shape (SS-shape) statistics are both exploited. The PB-shape model is trained offline from ground-truth kidney segmentations of various subjects, whereas the SS-shape model is trained on the fly using the segmentation results that are obtained for a specific subject. The proposed method was evaluated on the real medical datasets of 45 subjects and reports a Dice similarity coefficient (DSC) of 0.953 ± 0.018, an intersection-over-union (IoU) of 0.91 ± 0.033, and 1.10 ± 1.4 in the 95-percentile of Hausdorff distance (HD95). Extensive experiments confirm the superiority of the proposed method over several state-of-the-art level set methods, with an average improvement of 0.7 in terms of HD95. It also offers an HD95 improvement of 9.5 and 3.8 over two deep neural networks based on the U-Net architecture. The accuracy improvements have been experimentally found to be more prominent on low-contrast and noisy images.

19.
Sci Rep ; 12(1): 18816, 2022 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335227

RESUMO

Early diagnosis of transplanted kidney function requires precise Kidney segmentation from Dynamic Contrast-Enhanced Magnetic Resonance Imaging images as a preliminary step. In this regard, this paper aims to propose an automated and accurate DCE-MRI kidney segmentation method integrating fuzzy c-means (FCM) clustering and Markov random field modeling into a level set formulation. The fuzzy memberships, kidney's shape prior model, and spatial interactions modeled using a second-order MRF guide the LS contour evolution towards the target kidney. Several experiments on real medical data of 45 subjects have shown that the proposed method can achieve high and consistent segmentation accuracy regardless of where the LS contour was initialized. It achieves an accuracy of 0.956 ± 0.019 in Dice similarity coefficient (DSC) and 1.15 ± 1.46 in 95% percentile of Hausdorff distance (HD95). Our quantitative comparisons confirm the superiority of the proposed method over several LS methods with an average improvement of more than 0.63 in terms of HD95. It also offers HD95 improvements of 9.62 and 3.94 over two deep neural networks based on the U-Net model. The accuracy improvements are experimentally found to be more profound on low-contrast images as well as DCE-MRI images with high noise levels.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Análise por Conglomerados , Rim/diagnóstico por imagem
20.
Biomedicines ; 11(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36672514

RESUMO

The dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) technique has great potential in the diagnosis, therapy, and follow-up of patients with chronic kidney disease (CKD). Towards that end, precise kidney segmentation from DCE-MRI data becomes a prerequisite processing step. Exploiting the useful information about the kidney's shape in this step mandates a registration operation beforehand to relate the shape model coordinates to those of the image to be segmented. Imprecise alignment of the shape model induces errors in the segmentation results. In this paper, we propose a new variational formulation to jointly segment and register DCE-MRI kidney images based on fuzzy c-means clustering embedded within a level-set (LSet) method. The image pixels' fuzzy memberships and the spatial registration parameters are simultaneously updated in each evolution step to direct the LSet contour toward the target kidney. Results on real medical datasets of 45 subjects demonstrate the superior performance of the proposed approach, reporting a Dice similarity coefficient of 0.94 ± 0.03, Intersection-over-Union of 0.89 ± 0.05, and 2.2 ± 2.3 in 95-percentile of Hausdorff distance. Extensive experiments show that our approach outperforms several state-of-the-art LSet-based methods as well as two UNet-based deep neural models trained for the same task in terms of accuracy and consistency.

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