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Desulphurization of fossil fuels is a critical process in reducing the sulphur content from environment, which is a major contributor to atmospheric pollution. Traditional desulphurization techniques, while effective, often involve high energy consumption and the use of harsh chemicals. Recently, photocatalytic desulphurization has emerged as a promising, eco-friendly alternative, leveraging the potential of photocatalysts especially semiconductor heterojunctions to enhance photocatalytic efficiency. This review comprehensively discusses the significance and mechanism of photocatalytic desulphurization reactions, designing of various heterojunctions such as conventional, p-n, Z-scheme and S-scheme, their charge transfer mechanism and properties and their contribution to the photocatalytic desulphurization activity. Heterojunctions, formed by combining different semiconductor materials, facilitate efficient charge separation and broaden the light absorption range, thereby improving the photocatalytic performance under visible light. Furthermore, the recent advancements in the heterojunction systems in the field of photocatalytic desulphurization activity have been discussed in detail and summarized. The current limitations and challenges in this particular field are also explored. The paper concludes with an outlook on future research directions and the potential industrial applications of heterojunction-powered photocatalytic desulphurization, emphasizing its role in achieving cleaner energy production and environmental sustainability.
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The possible impact of antivirals on ecosystems and the emergence of antiviral resistance are the reasons for concern about their environmental release. Consequently, there has been a significant increase in curiosity regarding their presence in both organic and synthetic systems in recent years. The primary objective of this review is to address the void of information regarding the global presence of antiviral drugs in both wastewater and natural water sources. Photocatalytic degradation of pollutants is an eco-friendly, cost-effective method that effectively addresses environmental degradation. The development of efficient photocatalysts remains a significant issue in accelerating the degradation of pollutants, especially when employing solar light. Thus, the development of Z-scheme and S-scheme semiconductor heterojunctions has emerged as a viable method to improve light absorption and enhance the redox capability of photocatalysts. The principles of Z-scheme and S-scheme are reviewed extensively. The degradation route and occurrence of antiviral are discussed briefly. Finally, a short preview of the degradation of antiviral using Z-scheme and S-scheme is also highlighted.
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Antivirais , Antivirais/química , Catálise , Poluentes Químicos da Água/química , Águas Residuárias/químicaRESUMO
In pursuit of advancing photocatalysts for superior performance in water treatment and clean energy generation, researchers are increasingly focusing on layered double hydroxides (LDHs) which have garnered significant attention due to their customizable properties, morphologies, distinctive 2D layered structure and flexible options for modifying anions and cations. No review has previously delved specifically into ZnCr and NiCr LDH-based photocatalysts and therefore, this review highlights the recent surge in ZnCr and NiCr-based LDHs as potential photocatalysts for their applications in water purification and renewable energy generation. The structural and fundamental characteristics of layered double hydroxides and especially ZnCr-LDHs and NiCr-LDHs are outlined. Further, the various synthesis techniques for the preparation of ZnCr-LDHs, NiCr-LDHs and their composite and heterostructure materials have been briefly discussed. The applicability of ZnCr-LDH and NiCr-LDH based photocatalysts in tackling significant issues in water treatment and sustainable energy generation is the main emphasis of this review. It focuses on photocatalytic degradation of organic pollutants in wastewater, elucidating the principles and advancements for enhancing the efficiency of these materials. It also explores their role in H2 production through water splitting, conversion of CO2 into valuable fuels and NH3 synthesis from N2, shedding light on their potential for clean energy solutions. The insights presented herein offer valuable guidance for researchers working towards sustainable solutions for environmental remediation and renewable energy generation.
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Hidróxidos , Purificação da Água , Hidróxidos/química , Catálise , Purificação da Água/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Energia Renovável , Águas Residuárias/químicaRESUMO
Microplastics (MPs), as emerging pollutants, have attracted the attention of environmentalists, statespersons, and the scientific community over the last few decades. To address the spread of MPs in the environment, it is imperative to develop various removal techniques and materials that are effective, scalable, and ecologically benign. However, to the best of our knowledge, no review has systematically examined the removal of MPs using adsorption or provided an in-depth discussion on various adsorbents. Adsorption is an inexpensive and effective technology for wastewater treatment. Recently, many researchers have conducted studies on MP remediation using diverse adsorbent materials, such as biochar, activated carbon, sponges, carbon nanotubes, metal-layered oxides, metal-organic frameworks (MOFs), and zeolites. Each adsorbent has advantages and disadvantages. To overcome their disadvantages, researchers have been designing and developing hybrid adsorbents for MP remediation. This review provides insights into these individual adsorbents and also discusses hybrid adsorbents for MP removal. Finally, the review elaborates on future possibilities and ways to enable more efficient, scalable, and environmentally friendly MP cleanup. Overall, this review bridges the gap between contemporary MP remediation using adsorption techniques and adsorbent development.
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Poluentes Ambientais , Nanotubos de Carbono , Poluentes Químicos da Água , Purificação da Água , Água , Poluentes Químicos da Água/análise , Plásticos , Microplásticos , Adsorção , Óxidos , Purificação da Água/métodosRESUMO
Pectin-crosslinked gum ghatti hydrogel (PGH) has been synthesized utilizing pectin and gum ghatti through an uncomplicated and inexpensive copolymerization method. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM-elemental mapping), Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS) characterization techniques have been employed to determine various structural, chemical and compositional characteristics of fabricated PGH. Three different weight ratios (1:1, 2:1, or 1:2 for pectin and gum ghatti, respectively) were employed to synthesize three distinct types of PGH. Swelling studies has been done to determine the best ratios for PGH fabrication. PGH has been assessed as an adsorbent for the removal of malachite green dye from aqueous solutions. The effects of PGH dosage (100-400 mg/L), dye concentration (10-160 mg/L), pH (2-9 pH), adsorption time (0-480 min), and temperature (25-55 °C) has been examined through batch solutions. According to Langmuir isotherm analysis, the maximum adsorption capacity is 658.1 mg/g. By using pseudo-second-order kinetics and the Freundlich adsorption isotherm, the adsorption process could be well explained. After five consecutive cycles, PGH had an adsorption percentage of 86.917 % for the malachite green dye. It is safe for the environment and may be used to remove malachite green (MG) dye from aqueous solutions.
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Hidrogéis , Gomas Vegetais , Corantes de Rosanilina , Poluentes Químicos da Água , Hidrogéis/química , Adsorção , Pectinas , Espectroscopia de Infravermelho com Transformada de Fourier , Cinética , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/químicaRESUMO
The present paper describes the design of shape-oriented hydrogel nanospheres using a facile ultrasonication-supported crosslinked copolymerization technique. The effect of variable monomer concentration on the homogeneity of hydrogel nanospheres was investigated. The chitosan-cl-poly(MMA) hydrogel nanospheres were well characterized using various techniques such as FTIR, XRD, TGA, SEM, and TEM. The chitosan-cl-poly(MMA) hydrogel nanospheres were studied for their swelling behavior and could potentially be used as a novel adsorbent for rhodamine B dye remediation from aqueous media. The study found that utilizing chitosan-cl-poly(MMA) nanohydrogel spheres at the optimal pH 5 increased RhB dye adsorption capacity from 7.9 to 17.8 mg/g (pH 2 to 5), followed by a slight reduction. Furthermore, when nanohydrogel concentration increased, adsorption capacity dropped from 18.03 to 2.8 mg/g, but adsorption percentage climbed from 90.2% to 97.8%. At an initial dye concentration of 140 mg/L, rhodamine B adsorption achieved 204.3 mg/g in 60 min. The rhodamine B dye adsorption study includes adsorption kinetics, isotherm, and thermodynamics analyses. The interpretation of the adsorption study revealed that Langmuir isotherms fit best with a qmax value of 276.26 mg/g, which is in close approximation with the experimental value, whereas pseudo-second-order kinetics explains the adsorption process rate. The interaction of RhB dye with chitosan-cl-poly(MMA) hydrogel nanospheres involves multiple forces such as electrostatic interactions, hydrogen bonding, van der Waals forces, etc.
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The dramatic rise in carbon dioxide levels in the atmosphere caused by the continuous use of carbon fuels continues to have a significant impact on environmental degradation and the disappearance of energy reserves. Past few years have seen a significant increase in the interest in photocatalytic carbon dioxide reduction because of its ability to lower CO2 releases from the burning of fossil fuels while also producing fuels and important chemical products. Because of their excellent catalytic efficiency, great uniformity, lengthy charge diffusion layers and texture flexibility that enable accurate band gap and band line optimization, perovskite-based nanomaterials are perhaps the most advantageous among the numerous semiconductors proficient in accelerating CO2 conversion under visible light. Firstly, a brief insight into photocatalytic CO2 conversion mechanism and structural features of perovskites are discussed. Further the classification and selection of perovskites for Z and S-scheme heterojunctions and their role in photocatalytic CO2 reduction analysed. The efficient modification and engineering of heterojunctions via co-catalyst loading, morphology control and vacancy introduction have been comprehensively reviewed. Third, the state-of-the-art achievements of perovskite-based Z-scheme and S-scheme heterojunctions are systematically summarized and discussed. Finally, the challenges, bottlenecks and future perspectives are discussed to provide a pathway for applying perovskite-based heterojunctions for solar-to-chemical energy conversion.
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Dióxido de Carbono , Óxidos , Atmosfera , Compostos de CálcioRESUMO
Antibiotic water contamination is a growing environmental problem in the present day. As a result, water treatment is required for its reduction and elimination. Due to their important role in resolving this issue, photocatalysts have drawn a great deal of interest over the past few decades. When non-biodegradable organic matter is present in polluted water, the photo catalytic process, which is both environmentally friendly and an improved oxidation method, can be an effective means of remediation. In this regard, we report the successful synthesis of pure phased rare earth doped ZnO nanoparticles for tetracycline degradation. The prepared catalysts were systematically characterized for structural, optical, and magnetic properties. The optical band gap was tailored by rare earth doping, with redshift for Sm and Dy doped nanoparticles and blueshift for Nd doped ZnO nanoparticles. The analysis of photoluminescence spectra revealed information about the defect chemistry of all synthesised nanoparticles. Magnetic studies revealed that all synthesized diluted magnetic semiconductors exhibit room temperature ferromagnetism and can be employed for spintronic applications. Moreover, Dy doped ZnO nanoparticles were found to exhibit a maximum degradation efficiency of 74.19% for tetracycline (TCN) removal. The synthesized catalysts were also employed for the degradation of Malachite green (MG), and Crystal violet (CV) dyes. The maximum degradation efficiency achieved was 97.18% for MG and 98% for CV for Dy doped ZnO nanoparticles. The degradation mechanism involved has been discussed in view of the reactive species determined from scavenging experiments.
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In the present work, mixed-spinel ferrite anchored onto graphitic carbon nitride (GCN) was synthesized for mineralization of antibiotic pollutant from waste water. A Z-scheme g-C3N4/Ni0.5Zn0.5Fe2O4 nano heterojunction was fabricated by three step procedure: pyrolysis, solution combustion and mechanical grinding followed by annealing. The prepared photocatlyst was tested for degradation of Doxycycline (DC) drug under the natural sun light. Results revealed that the prepared heterojunction has maximum degradation efficiency of 97.10% pollutant in 60 min experiment. The Z-scheme heterojunction between g-C3N4 and Ni-Zn ferrite improves the photoinduced charges separation and protection of redox capability and therby increases the photo degradation efficiency. The scavenging experiments suggested that O2-â and h+ as main active species responsible for degradation of the antibiotic. In addition, the dopant variation can drive the shists in band gap and energy band positiong too which makes then excellent candidates for synthesizing tunable heterostructures with organic semiconductors. The work focusses on designing and developing of saimpler but efficient magnetic heterojunctions with superior redox capability for solar powered waste water treatment.
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Doxiciclina , Poluentes Ambientais , Catálise , Luz , Antibacterianos , ZincoRESUMO
Constructing visible-light-active Z-scheme heterojunctions has proven fruitful in enhancing the photocatalytic activity of photocatalysts for superior water clean-up. Herein, we report the fabrication of a CoFe2O4@Bi2O3/NiO (CBN) Z-scheme nanoheterojunction. The obtained CBN heterojunction was used for visible-light-assisted degradation of ofloxacin (OFL) in water. The OFL degradation efficiency achieved by the CBN heterojunction was 95.2% in 90 min with a rate constant of kapp = 0.03316 min-1, which was about eight times that of NiO and thirty times that of CoFe2O4. The photocatalytic activity of a Bi2O3/NiO Z-scheme heterojunction was greatly enhanced by the visible activity and redox mediator effect of the cobalt ferrite co-catalyst. Higher charge-carrier separation, more visible-light capture, and the Z-scheme mechanism in the Z-scheme system were the important reasons for the high performance of CBN. The scavenging experiments suggested âO2- as an active species for superior OFL degradation. The possible OFL degradation pathway was predicted based on LC-MS findings of degradation intermediate products. The magnetic nature of the CBN helped in the recovery of the catalyst after reuse for six cycles. This work provides new insights into designing oxide-based heterojunctions with high visible-light activity, magnetic character, and high redox capabilities for potential practical applications in environmental treatment.
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Ofloxacino , Catálise , Cromatografia Líquida , Frutas , ÁguaRESUMO
Background The association between hypothyroidism and iron-deficiency anemia (IDA) in pregnancy is not well established. Hence, this study aimed to investigate the association between hypothyroidism and IDA during the first trimester of pregnancy. Methodology In this study, a total of 144 pregnant women were included. Thyroid-stimulating hormone (TSH), free T4 (FT4), free T3 (FT3), and ferritin were measured. Based on TSH values, pregnant women were divided into the following two groups: euthyroid (n = 74) and hypothyroid (n = 70). Results There was a significant increase in TSH levels and a significant decrease in the levels of FT4, FT3, ferritin, iron, and hemoglobin (Hb) in hypothyroid pregnant women compared to euthyroid pregnant women. The correlation and regression analysis revealed a significant negative association of TSH and a positive association of FT4 with ferritin, iron, and Hb. Conclusions These findings demonstrate the association of hypothyroidism with IDA during the first trimester of pregnancy. Further studies with thyroxine therapy in hypothyroid pregnant women and its impact on IDA will open novel therapeutic approaches in the management of IDA during pregnancy. Further, measurement of serum ferritin during pregnancy may provide valuable information in the diagnosis and management of IDA.
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Herein, we report the designing of a C3N4/BiOI heterostructure that is supported on gum acacia-crosslinked-poly(acrylamide) hydrogel to fabricate a novel nanocomposite hydrogel. The potential application of the obtained nanocomposite hydrogel to remediate crystal violet dye (CVD) in an aqueous solution was explored. The structural and functional analysis of the nanocomposite hydrogel was performed by FTIR (Fourier transform infrared spectroscopy), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The different reaction parameters, such as CVD concentration, nanocomposite hydrogel dosage, and working pH, were optimized. The C3N4/BiOI heterostructure of the nanocomposite hydrogel depicts Z-scheme as the potential photocatalytic mechanism for the photodegradation of CVD. The degradation of CVD was also specified in terms of COD and HR-MS analysis was carried to demonstrate the major degradation pathways.
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Vitamin B12 and folate deficiency leads to accumulation of homocysteine that increases the risk of adverse pregnancy outcomes like preterm birth and low birth weight (LBW) of the neonate. We explored the association of genetic variants of key vitamin B12 and folate metabolising enzymes (MTHFR C677T and A1298C, MTR A2756G, TCN-2 C776G) with preterm birth and LBW in South Indian women. MTHFR A1298C heterozygotes (AC) were at higher risk for preterm delivery, whereas TCN-2 C776G heterozygotes (CG) were at higher risk for both preterm delivery and LBW. MTHFR C677T, A1298C and MTR A2756G haplotype CAG was protective for preterm delivery (p=.036, OR = 0.475; 95% CI: 0.233-0.97), whereas, haplotype CCG increasing the risk of preterm birth by 1.8 folds (p=.018, OR = 1.81; 95% CI: 1.09-2.98). These results underscore the significance of vitamin B12 and folate in the pathophysiology of preterm birth and LBW.Impact StatementWhat is already known on this subject? Polymorphisms of vitamin B12 and folate metabolising genes have been reported to influence preterm birth and LBW, but the reports are not consistent.What do the results of this study add? We observed a relationship of MTHFR A1298C and TCN-2 C776G with preterm birth, and significant association of TCN-2 C776G with LBW in infants.What are the implications of these findings for clinical practice and/or further research? Identification of women carrying these polymorphic risk alleles may benefit from early nutritional modifications.
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Metilenotetra-Hidrofolato Redutase (NADPH2) , Nascimento Prematuro , Vitamina B 12 , Estudos de Casos e Controles , Feminino , Ácido Fólico/metabolismo , Genótipo , Homocisteína , Humanos , Lactente , Recém-Nascido , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Gravidez , Resultado da Gravidez , Nascimento Prematuro/genéticaRESUMO
This work reports synthesis of a dual-function facile heterojunction and investigation of role of the charge transfer dynamism between individual semiconductor components for superior photocatalytic and electrochemical sensing application. The bio-benevolent and sturdy ZnO/Fe2O3 heterojunctions were utilized for visible light facilitated photo-degradation of sulfamethoxazole (SMX) antibiotic and electrochemical sensing of dopamine drug (DA). The fabricated heterojunction were characterized for structural, optical, and magnetic properties. Structural studies revealed the formation of nano heterojunction containing both phases. Magnetic studies confirmed the highly pure magnetic nature of photocatalysts. ZnO/30 wt%Fe2O3 heterojunction (S2) shows 95.2% SMX degradation under visible light and high retention of performance under solar light. The scavenging experiments infer that OH radicals are the active species responsible for degradation. A Z-scheme photocatalytic mechanism was predicted for higher performance with protection of high potential VB of ZnO and CB of Fe2O3 for high generation of reactive oxygen species. LC-MS was employed to predict a plausible degradation route. The sample modified glassy carbon electrodes (GCE) were used for electrochemical sensing of dopamine via cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The S2 junction exhibited 0.18 µM limit of detection with concentration range of 1 µM-50 µM. The stability test was successfully carried out at room temperature for 15 days. In addition, the S2 modified electrodes were spiked in real urine samples and good results were obtained. DPV reveals that S2 modified electrode is best sensor for dopamine sensing among all synthesized heterojunctions. The detection mechanism was also discussed in detail. The in-built metal redox i.e Zn2+/Zn+ and Fe3+/Fe2+ facilitate the Z-scheme transfer, improve the charge transfer capacity and reduce the recombination. This study is beneficial because it reports utilization of popular and well-tested semiconductor metal oxides to form heterojunctions with dual capabilities of environmental detoxification and cost-effective electrochemical detection of biomolecules.
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Dopamina , Óxido de Zinco , Luz , Oxirredução , SulfametoxazolRESUMO
BACKGROUND: Vitamin B12 is an essential micronutrient for neurological function, as it leads to the regeneration of methionine from homocysteine, which is precursor of biologically active molecule S-Adenosyl Methionine (SAM). Pregnancy is a state of increased demand and delayed postpartum repletion of nutrients may predispose women to depression. METHODS: We included women who visited the hospital at 6-weeks postpartum for a regular checkup. Inclusion criteria were age (18-50 years), and willingness to donate venous sample for analysis. Exclusion criteria included previous history of mood disorders or antidepressant medication use, and any systemic illness like hypothyroidism, epilepsy, diabetes, and hypertension. Based on EPDS score of 10 as a cutoff, 217 women with probable postpartum depression (PPD) and equal number of age and BMI matched controls were included. Plasma total vitamin B12, holotranscobalamin (holotc), homocysteine (hcy), methyl malonic acid (MMA), 5-methyl tetrahydrofolate (THF), SAM and serotonin levels were estimated using commercially available ELISA kits. Combined B12 (cB12) score was calculated from study parameters. Multivariate analysis was performed to assess the risk of probable postpartum depression. RESULTS: Total vitamin B12 and combined B12 score were found to be significantly lower (p = 0.001) and MMA (p = 0.002) and 5-methyl THF (p < 0.001) levels were higher in women with probable depression than women without probable PPD. Women in the lowest vitamin B12 quartile had 4.53 times higher likelihood of probable postpartum depression (p < 0.001). Multivariate analysis demonstrated that decreasing vitamin B12 (OR = 0.394; 95% CI: 0.189-0.822) and cB12 (OR = 0.293; 95% CI: 0182-0.470) and increasing MMA (OR = 2.14; 95% CI: 1.63-2.83) and 5-methyl THF levels (OR = 3.29; 95% CI: 1.59-6.83) were significantly associated with the risk of probable PPD. CONCLUSION: Low vitamin B12 may contribute to depressive symptoms in vulnerable postpartum period.
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Depressão Pós-Parto/sangue , Homocisteína/sangue , Ácido Metilmalônico/sangue , S-Adenosilmetionina/sangue , Serotonina/sangue , Tetra-Hidrofolatos/sangue , Deficiência de Vitamina B 12/sangue , Vitamina B 12/sangue , Adolescente , Adulto , Cesárea/estatística & dados numéricos , Estudos Transversais , Depressão Pós-Parto/epidemiologia , Dieta/estatística & dados numéricos , Feminino , Humanos , Índia/epidemiologia , Gravidez , Gravidez não Planejada , Fatores de Risco , Classe Social , Transcobalaminas/metabolismo , Deficiência de Vitamina B 12/epidemiologia , Adulto JovemRESUMO
INTRODUCTION: Gestational impaired glucose tolerance (GIGT) is a milder form of gestational diabetes mellitus (GDM), which is often poorly managed. Although, GDM is known to be associated with increased incidence of thyroid dysfunction, no study has been done to study the effect of GIGT on thyroid status and its effect on fetal outcome. Here, we carried out a study to assess thyroid function and glycemic status in both maternal and cord blood of the subjects with GIGT, and to find their association with the fetal outcome. MATERIALS AND METHODS: Women who came to the hospital for safe confinement during 37-40th weeks of gestation were recruited in the study. Based on the 2 hours post prandial blood glucose levels with 75 grams OGTT, done at 24-28 weeks of gestation, all the subjects were stratified into two groups: (1) Cases or GIGT group - women with blood glucose levels between 120 and 140 mg/dl and (2) Controls - women with blood glucose levels of less than 120 mg/dl. Three milliliters of venous blood was collected from mothers and 3 ml of cord blood was collected during delivery. New-borns were assessed for birth weight, head circumference, abdominal circumference, thigh circumference, and crown-heel length. Glycated hemoglobin was carried out using immunoturbidimetry (DiaSys Diagnostic Systems GmbH, Holzheim, Germany) and fructosamine was estimated using dye binding method (Biosystems, Spain). Estimation of total T3 (TT3), free T3 (FT3), total T4 (TT4), free T4 (FT4), and TSH was done by chemiluminescence in Siemens Advia Centaur CP using competitive immunoassay. RESULTS: Although within the normal reference range, GIGT mothers had higher concentration of free and total T4 than controls. Cord fructosamine levels were significantly higher in babies of GIGT mothers than controls, indicating the reflection of maternal hyperglycemia. There was a positive correlation between the maternal glycated hemoglobin and cord blood fructosamine in the GIGT group. Statistically significant lower levels of total T3 and T4 with high TSH levels were found in babies with GIGT mothers, indicating the suppressive effect of maternal hyperglycemia on fetal thyroid function. Birth weight, head circumference, and thigh circumference were significantly higher in babies born to mothers with GIGT, which may be a combined effect of maternal hyperglycemia and fetal thyroid suppression. CONCLUSIONS: Maternal hyperglycemia, even in milder form of GIGT may cause suppression of fetal thyroid function. Both these factors may predispose to change in fetal anthropometry, leading to a large baby. Therefore, it is recommended to evaluate maternal and cord thyroid function for timely management strategies.
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Peso ao Nascer , Diabetes Gestacional/sangue , Estado Pré-Diabético/sangue , Hormônios Tireóideos/sangue , Adulto , Estudos de Casos e Controles , Diabetes Gestacional/fisiopatologia , Feminino , Humanos , Recém-Nascido , Estado Pré-Diabético/fisiopatologia , Gravidez , Estudos Prospectivos , Glândula Tireoide/fisiopatologia , Adulto JovemRESUMO
The effect of Co2+ substitution into nanocrystalline Mg-Mn ferrite synthesized by a solution combustion technique has been studied. The cation distribution has been inferred from X-ray diffraction, the magnetization technique, and Mössbauer spectroscopy. The X-ray analysis and cation distribution data have been used to investigate the detailed structural parameters such as hopping lengths, ionic radii of tetrahedral and octahedral sites, oxygen positional parameter, site bond as well as edge lengths, bond lengths, and bond angles. The variation in the theoretically predicted bond angles suggested the strengthening of the A-B super-exchange interactions, and the same has been supported by M-H and M-T, as well as by Mössbauer studies. The ZFC-FC study revealed that anisotropy increases with the incorporation of cobalt ions. The values of magneton number, theoretical lattice parameter, and Curie temperature that have been calculated by using the cation distribution are found to match well with the experimentally obtained values.
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As there are no specific non-invasive markers for the diagnosis of tubal ectopic pregnancy, our objective in the present study was to explore the role of inflammatory cytokines IL-6 and IL-8 in the diagnosis of ruptured tubal ectopic pregnancy. Twenty-eight women with tubal ectopic pregnancy, 31 patients with intrauterine abortion and 29 gestational age matched women having normal intrauterine pregnancy were included in the study. Five millilitre of blood was collected at the time of admission, serum was separated and stored at -70 °C for subsequent analysis of ß hCG, IL-6 and IL-8 levels. The level of IL-6 was a significant increase in the women with tubal ectopic pregnancy compared to intrauterine abortion and normal pregnancy. IL-8 levels decrease significantly in the tubal ectopic pregnancy and in intrauterine abortion patients when compared with the normal pregnancy group. At the cutoff of 26.48 pg/ml IL-6 level predicted the tubal ectopic pregnancy with moderate accuracy. Therefore, it can be concluded that measurement of IL-6 may have relevance in the diagnosis of ectopic pregnancy as a novel inflammatory serum biomarkers.
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Interleucina-6/sangue , Interleucina-8/sangue , Gravidez Tubária , Adulto , Biomarcadores/sangue , Feminino , Humanos , Índia , Inflamação/sangue , Gravidez , Gravidez Tubária/sangue , Gravidez Tubária/diagnóstico , Gravidez Tubária/fisiopatologia , Reprodutibilidade dos TestesRESUMO
We evaluated the diagnostic accuracy of activin B in discriminating tubal ectopic pregnancy (tEP) from intrauterine miscarriages (IUM), and normal viable intrauterine pregnancy (IUP). We included 28 women with tEP, 31 women with IUM, and 29 normal IUP, confirmed both by clinical examination and ultrasonography. Serum activin B concentration was measured at the time of admission using the ELISA kit. The median serum activin B concentration was found to be significantly decreased in both tEP (p=0.004) and IUM (p=0.022) compared to normal IUP. When compared between tEP and IUM, activin B concentrations did not differ significantly. ROC analysis of activin B and free ß-hCG demonstrated AUC of 0.722 and 0.805, respectively to discriminate tEP from viable IUP. The model including both activin B and free ß-hCG improved the discriminating potential with greater AUC (0.824), and specificity (93%) than individual one. To discriminate tEP from IUM, activin B, free ß-hCG and combination of both performed poorly. We conclude that serum activin B concentration is lower in tubal ectopic pregnancy, and can discriminate it from normal pregnancy with moderate accuracy. It also shows improved diagnostic potential along with free ß-hCG, but cannot distinguish tEP from IUM reliably.
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Aborto Espontâneo/diagnóstico , Ativinas/sangue , Biomarcadores/sangue , Gravidez Ectópica/diagnóstico , Aborto Espontâneo/sangue , Adulto , Estudos de Casos e Controles , Gonadotropina Coriônica/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Gravidez Ectópica/sangue , Estudos Prospectivos , Curva ROC , Adulto JovemRESUMO
OBJECTIVES: To evaluate the diagnostic role of cerebrospinal fluid (CSF) ferritin and albumin index (AI = CSF albumin/serum albumin × 1000) in differentiating acute bacterial meningitis (ABM) from acute viral meningitis (AVM) in children. METHODS: The study included 42 cases each of ABM and AVM in pediatric age group. Receiver operating characteristic (ROC) analysis was carried out for CSF ferritin and AI. Binary logistic regression was also done. RESULTS: CSF ferritin and AI were found significantly higher in ABM compared to AVM. Model obtained using AI and CSF ferritin along with conventional criteria is better than existing models.