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1.
Environ Sci Pollut Res Int ; 31(17): 26261-26281, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38499921

RESUMO

Nutrient imbalances may negatively affect the health status of forests exposed to multiple stress factors, including drought and bark beetle calamities. We studied the origin of base cations in runoff from a small Carpathian catchment underlain by base-poor flysch turbidites using magnesium (Mg), calcium (Ca) and strontium (Sr) isotope composition of 10 ecosystem compartments. Our objective was to constrain conclusions drawn from long-term hydrochemical monitoring of inputs and outputs. Annual export of Mg, Ca and Sr exceeds 5-to-15 times their atmospheric input. Mass budgets per se thus indicate sizeable net leaching of Mg, Ca and Sr from bedrock sandstones and claystones. Surprisingly, δ26Mg, δ44Ca and 87Sr/86Sr isotope ratios of runoff were practically identical to those of atmospheric deposition and soil water but significantly different from bedrock isotope ratios. We did not find any carbonates in the studied area as a hypothetical, easily dissolvable source of base cations whose isotope composition might corroborate the predominance of geogenic base cations in the runoff. Marine carbonates typically have lower δ26 Mg and 87Sr/86Sr ratios, and silicate sediments often have higher δ26Mg and 87Sr/86Sr ratios than runoff at the study site. Mixing of these two sources, if confirmed, could reconcile the flux and isotope data.


Assuntos
Cálcio , Magnésio , Cálcio/análise , Magnésio/análise , Ecossistema , Monitoramento Ambiental , Isótopos de Estrôncio/análise , Isótopos , Cátions , Carbonatos
2.
Nutrients ; 16(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38542681

RESUMO

Preeclampsia is a primary placental disorder, with impaired placental vascularization leading to uteroplacental hypoperfusion. We aimed to investigate differences in metal and metalloid content between the placentas of women with preeclampsia and healthy controls. This was a case-control study in 63 women with preeclampsia and 113 healthy women. Clinical data were obtained from medical records. Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure the placental metals and metalloids content. Compared with healthy control subjects, preeclampsia was associated with a significantly lower concentration of essential elements (magnesium, calcium, iron, copper, zinc, and selenium) in the placental tissue. After multivariable adjustment, an interquartile range (IQR) increase in selenium concentration was associated with a reduced risk of preeclampsia with an OR of 0.50 (95% CI: 0.33-0.77). The joint effects of multiple selected metals and metalloids were associated with a reduced risk of preeclampsia. The lower placental magnesium, chromium, iron, zinc, and selenium concentrations of preeclampsia cases indicate a potential link to its pathogenesis. It also provides an intriguing avenue for future research in revealing the underlying mechanisms and potential intervention strategies for preeclampsia.


Assuntos
Metaloides , Pré-Eclâmpsia , Selênio , Gravidez , Feminino , Humanos , Placenta/química , Metaloides/análise , Estudos de Casos e Controles , Magnésio/análise , Zinco , Ferro/análise
3.
Geobiology ; 22(1): e12586, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38385602

RESUMO

The formation of skeletal structures composed of different calcium carbonate polymorphs (e.g. aragonite and calcite) appears to be both biologically and environmentally regulated. Among environmental factors influencing aragonite and calcite precipitation, changes in seawater conditions-primarily in the molar ratio of magnesium and calcium during so-called 'Calcite' (mMg:mCa below 2) or 'Aragonite' seas (mMg:mCa above 2)-have had profound impacts on the distribution and performance of marine calcifiers throughout Earth's history. Nonetheless, the fossil record shows that some species appear to have counteracted such changes and kept their skeleton polymorph unaltered. Here, the aragonitic octocoral Heliopora coerulea and the aragonitic scleractinian Montipora digitata were exposed to Calcite Sea-like mMg:mCa with various levels of magnesium and calcium concentration, and changes in both the mineralogy (i.e. CaCO3 polymorph) and gene expression were monitored. Both species maintained aragonite deposition at lower mMg:mCa ratios, while concurrent calcite presence was only detected in M. digitata. Despite a strong variability between independent experimental replicates for both species, the expression for a set of putative calcification-related genes, including known components of the M. digitata skeleton organic matrix (SkOM), was found to consistently change at lower mMg:mCa. These results support the previously proposed involvements of the SkOM in counteracting decreases in seawater mMg:mCa. Although no consistent expression changes in calcium and magnesium transporters were observed, down-regulation calcium channels in H. coerulea in one experimental replicate and at an mMg:mCa of 2.5, pointing to a possible active calcium uptake regulation by the corals under altered mMg:mCa.


Assuntos
Antozoários , Carbonato de Cálcio , Animais , Carbonato de Cálcio/análise , Cálcio/metabolismo , Antozoários/química , Antozoários/metabolismo , Magnésio/análise , Oceanos e Mares
4.
J Trace Elem Med Biol ; 83: 127388, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38262193

RESUMO

BACKGROUND: In women of childbearing age, a low dietary supply of iron, calcium, and magnesium is often observed. Minerals deficiency in pregnant women is often associated with abnormal body weight and may impact fetal development disorders. The aim of this study is to determine the relationship between prepregnancy body mass index (BMI) and the dietary intake of iron, calcium and magnesium and their concentrations in serum and hair in pregnant women. METHOD: The study involved 97 Caucasian/white low-risk pregnant women at 12 weeks of gestation. The analysis of minerals in serum and hair samples was performed using atomic absorption spectrometry. Pre-pregnancy BMI was calculated based on self-reported weight. The study used a validated questionnaire and a 24-h recall nutrition interview, which were analyzed using Aliant software. RESULTS: It was found that overweight and obese women exhibited higher magnesium concentration in serum, while iron content in serum and hair was markedly lower compared to women with normal body weight. The average total supply of iron was below the recommendation in pregnant women. Moreover, an inverse significant relationship was observed between BMI and iron concentration in hair and serum in the whole population. CONCLUSION: In conclusion, being overweight or obese before pregnancy is associated with low dietary iron intake and low iron concentration in serum and hair during the first trimester of pregnancy in women.


Assuntos
Ferro , Magnésio , Feminino , Humanos , Gravidez , Índice de Massa Corporal , Magnésio/análise , Ferro/análise , Cálcio/análise , Primeiro Trimestre da Gravidez , Sobrepeso , Minerais/análise , Obesidade , Cabelo/química
5.
Sci Total Environ ; 916: 170294, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38272080

RESUMO

Calcium-silicon-magnesium-potassium fertilizer (CSMP) is usually used as an amendment to counteract soil acidification caused by historical excessive nitrogen (N) applications. However, the impact of CSMP addition on phosphorus (P) mobilization in acidic soils and the related mechanisms are not fully understood. Specifically, a knowledge gap exists with regards to changes in soil extracellular enzymes that contribute to P release. Such a knowledge gap was investigated by an incubation study with four treatments: i) initial soil (Control), ii) urea (60 mg kg-1) addition (U); iii) CSMP (1%) addition (CSMP) and iv) urea (60 mg kg-1) and CSMP (1%) additions (U + CSMP). Phosphorus mobilization induced by different processes was distinguished by biologically based P extraction. The Langmuir equation, K edge X-ray absorption near-edge structure spectroscopy, and ecoenzyme vector analysis according to the extracellular enzyme activity stoichiometry were deployed to investigate soil P sorption intensity, precipitation species, and microbial-driven turnover of organophosphorus. Results showed that CaCl2 extractable P (or citric acid extractable P) content increased by 63.4% (or 39.2%) in the soil with CSMP addition, compared with the study control. The accelerated mobilization of aluminum (Al)/iron (Fe)-bound P after CSMP addition, indicated by the reduction of the sum of FePO4·2H2O and AlPO4 proportion, contributed to this increase. The decrease of P sorption capacity can also be responsible for it. The CSMP addition increased enzyme extractable P in the soil nearly 7-fold and mitigated the limitations of carbon (C) and P for soil microorganisms (indicated by the enzyme stoichiometry and ecoenzyme vector analysis), suggesting that microbial turnover processes also contribute to P mobilization in amended acidic soil. These findings indicate that the P mobilization in CSMP amended acidic soil not only attributed to both decreasing P sorption capacity and dissolving phosphate precipitation, but also to the increase of the microbial turnover of the organophosphorus pool.


Assuntos
Cálcio , Fósforo , Fósforo/análise , Cálcio/análise , Solo/química , Magnésio/análise , Silício , Fertilizantes/análise , Potássio/análise , Fosfatos/análise , Ureia
6.
J Sci Food Agric ; 104(3): 1824-1832, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37884460

RESUMO

BACKGROUND: Rice taste is closely associated with endosperm composition, which varies among different rice layers. Although clarifying the relationship between this difference and nutritional taste can guide rice breeding and cultivation practices, research on this topic is limited. RESULTS: Here, typical rice varieties having excellent and poor taste characteristics were selected to analyze the distribution characteristics and differences of their components. The varieties with excellent taste exhibited lower apparent amylose content (AAC) and protein content (PC), lesser short-chain (Fa) and long-chain (Fb3 ) amylopectin (AP) and more medium-chain (Fb1+2 ) AP, higher long-to-short chain ratio (Fa:Fb3 ), and higher nitrogen (N), magnesium (Mg) and calcium (Ca) content in layer 1 (L1) than the varieties with poor taste. Layer 2 (L2) played a key role in AAC and PC regulation in the varieties with excellent taste by reducing AAC and appropriately increasing PC, consequently improving rice taste. AP structure in layer 3 (L3) substantially affected the taste of the two types of varieties. The mineral content was the highest in L1, and increased potassium (K), Ca, and Mg content improved taste in all varieties. CONCLUSION: AAC in each layer contributes to rice taste. PC and minerals primarily act on L1 and L2, whereas AP acts on L2 and L3. Therefore, the endosperm formation process should be exploited for improving rice taste. Furthermore, key resources and cultivation should be identified and regulated, respectively, to improve rice taste. © 2023 Society of Chemical Industry.


Assuntos
Oryza , Oryza/química , Paladar , Melhoramento Vegetal , Amilopectina/química , Endosperma/química , Amilose/análise , Minerais/análise , Magnésio/análise , Amido/química
7.
Food Chem ; 438: 137976, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37980870

RESUMO

Pansy and viola edible flowers were grown hydroponically with different levels of Mg and Mn. The nutritional composition was determined using standard methods. Free sugars, fatty acids, organic acids, tocopherols, and phenolic compounds were analyzed using various HPLC and GC devises. The extract's antimicrobial, antioxidant, cytotoxicity, and anti-inflammatory activity were assessed. The results indicated that Mg enrichment negatively affected plant growth and mineral accumulation but improved photosynthetic performance. The edible flowers contained significant amounts of protein, low levels of fat, and varying sugar contents, such as glucose and fructose. Various fatty acids and phenolic compounds were identified, with different concentrations depending on the treatment. The flowers exhibited antioxidant potential, antimicrobial activity, cytotoxic effects, and anti-inflammatory properties. The correlations between the investigated parameters not only expand knowledge on Mg and Mn interaction but also catalyze significant advancements in sustainable agriculture and food health, fostering a healthier and more conscious future.


Assuntos
Anti-Infecciosos , Viola , Antioxidantes/química , Viola/química , Magnésio/análise , Manganês/análise , Flores/química , Fenóis/análise , Ácidos Graxos/análise , Anti-Infecciosos/farmacologia , Anti-Infecciosos/análise , Anti-Inflamatórios/análise , Extratos Vegetais/química
8.
Appl Spectrosc ; 78(2): 243-250, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38083817

RESUMO

This study was dedicated to developing analytical methods for determining macronutrients (Ca, K, and Mg) in soy leaf samples with and without petioles. The study's primary purpose was to present Laser-induced breakdown spectroscopy (LIBS) as a viable alternative for directly analyzing leaf samples using chemometric tools to interpret the data obtained. The instrumental condition chosen for LIBS was 70 mJ of laser pulse energy, 1.0 µs of delay time, and 100 µm of spot size, which was applied to 896 samples: 305 of soy without petioles and 591 of soy with petioles. The reference values of the analytes for the proposition of calibration models were obtained using inductively coupled plasma optical emission spectroscopy (ICP-OES) technique. Twelve normalization modes and two calibration strategies were tested to minimize signal variations and sample matrix microheterogeneity. The following were studied: multivariate calibration using partial least squares and univariate calibration using the area and height of several selected emission lines. The notable normalization mode for most models was the Euclidean norm. No analyte showed promising results for univariate calibrations. Micronutrients, P and S, were also tested, and no multivariate models presented satisfactory results. The models obtained for Ca, K, and Mg showed good results. The standard error of calibration ranged from 2.3 g/kg for Ca in soy leaves without petioles with two latent variables to 5.0 g/kg for K in soy leaves with petioles with two latent variables.


Assuntos
Lasers , Espectroscopia Fotoeletrônica/métodos , Análise Espectral/métodos , Cálcio/análise , Cálcio/química , Potássio/análise , Potássio/química , Magnésio/análise , Magnésio/química
9.
Chemosphere ; 346: 140643, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37939924

RESUMO

The effects of two types of layered double hydroxides (LDH) in-situ treatment on sediment phosphorus (P) mobilization and microbial community's structure were studied comparatively. The results presented that magnesium/aluminum-based (MA) and magnesium/iron (MF)-based LDH displayed great phosphate uptake ability in aqueous solution in a broad pH range of 3-8. The maximum phosphate sorption capacity of MA was 64.89 mg/g, around four times greater than that of MF (14.32 mg/g). Most of phosphate bound by MA and MF is hard to re-liberate under reduction and ordinary pH (5-9) conditions. In the in-situ remediation, the MA and MF capping/amendment both prevented P migration from the sediment to the overlying water (OL-water) under long-term anaerobic conditions, and MA had a better interception efficiency compared to MF in the same application mode. MA amendment significantly reduced mobile P (Mob-P) content in sediment and could remain its stable Mob-P inactivation capacity over a wide pH range. On the contrary, MF amendment increased Mob-P content in sediment and exhibited a variable ability to inactivate Mob-P under elevated pH conditions. MF can decrease Mob-P content at pH of 7 and 11 but increase Mob-P content at pH of 8-10. Under resuspension conditions, MA and MF capping groups still maintained low P levels in OL-water, while MA capping simultaneously showed a certain degree of resistance to sediment resuspension, but it had a weaker stabilizing effect for sediment than MF. Microbial community analysis manifested neither MA nor MF addition observably altered the sediment microbial diversity, but impacted the functional microorganisms' abundance and reshaped the microbial community's structure, intervening the sediment-P stabilization. Viewed from environmental friendliness, control efficiency, stability of P fixation capacity, and application convenience, MA capping wrapped by fabric is more suitable for addressing internal P loading in eutrophic lakes and holds great potential application.


Assuntos
Fósforo , Poluentes Químicos da Água , Fósforo/química , Magnésio/análise , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Fosfatos/farmacologia , Fosfatos/análise , Água/química , Lagos/química , Alumínio/análise
10.
Nutr. clín. diet. hosp ; 43(4): 182-188, 13 dec. 2023. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-229958

RESUMO

Introducción: El aumento de la incidencia y prevalenciade la obesidad en la población infantojuvenil, el exceso deconsumo de sodio, colesterol y grasas saturadas son factoresque implican un incremento del riesgo cardiovascular en laedad adulta, y como consecuencia un problema de salud co-munitaria grave. Por ello se ha desarrollado el presente tra-bajo que incluye la segunda parte del Programa Bon Profitpara una alimentación saludable y responsable en el comedorescolar. Se ha evaluado: la calidad de los lípidos, (atendiendoa su composición en ácidos grasos, contenido en colesterol),así como el contenido en sodio (Na), Potasio(K) y Magnesio(Mg) de los menús servidos en el comedor escolar.Objetivo: Estudio y valoración de la composición en ácidosgrasos, colesterol, Na, K y Mg de los menús escolares, paraevaluar el riesgo cardiovascular, para posteriormente haceruna intervención nutricional: en diseño y elaboración de me-nús y en hábitos alimentarios, con el fin de corregir los me-nús ofertados por la empresa y prevenir el riesgo cardiovas-cular y de obesidad.Materiales y métodos: Se han valorado 28 menús queconstituyen un total de 56 platos. Cada plato se ha muestre-ado durante un periodo de tres meses, mediante método depesada directa, y valorado con el programa informáticoDIAL®, para determinar la composición lipídica: ácidos gra-sos saturados (AGS), monoinsaturados (AGM) y poliinsatura-dos (AGP), colesterol y contenido en sodio (Na), potasio(K) ymagnesio (Mg). Posteriormente se han comparado los valoresobtenidos con las recomendaciones nutricionales para la po-blación estudiada de 900 escolares entre 3 y 19 años.Conclusiones y resultados: Se puede concluir que tantoen los menús del colegio como en los del instituto, la compo-sición en AGS, AGM y AGP sobrepasa las recomendaciones (AU)


Assuntos
Dieta , Serviços de Saúde Escolar , Lipídeos/sangue , Ácidos Graxos/análise , Colesterol/análise , Magnésio/análise , Potássio/análise , Sódio/análise , Espanha/epidemiologia
11.
Environ Int ; 178: 108065, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37562341

RESUMO

The mobilisation of potentially harmful chemical constituents in wildfire ash can be a major consequence of wildfires, posing widespread societal risks. Knowledge of wildfire ash chemical composition is crucial to anticipate and mitigate these risks. Here we present a comprehensive dataset on the chemical characteristics of a wide range of wildfire ashes (42 types and a total of 148 samples) from wildfires across the globe and examine their potential societal and environmental implications. An extensive review of studies analysing chemical composition in ash was also performed to complement and compare our ash dataset. Most ashes in our dataset had an alkaline reaction (mean pH 8.8, ranging between 6 and 11.2). Important constituents of wildfire ash were organic carbon (mean: 204 g kg-1), calcium, aluminium, and iron (mean: 47.9, 17.9 and 17.1 g kg-1). Mean nitrogen and phosphorus ranged between 1 and 25 g kg-1, and between 0.2 and 9.9 g kg-1, respectively. The largest concentrations of metals of concern for human and ecosystem health were observed for manganese (mean: 1488 mg kg-1; three ecosystems > 1000 mg kg-1), zinc (mean: 181 mg kg-1; two ecosystems > 500 mg kg-1) and lead (mean: 66.9 mg kg-1; two ecosystems > 200 mg kg-1). Burn severity and sampling timing were key factors influencing ash chemical characteristics like pH, carbon and nitrogen concentrations. The highest readily dissolvable fractions (as a % of ash dry weight) in water were observed for sodium (18 %) and magnesium (11.4 %). Although concentrations of elements of concern were very close to, or exceeded international contamination standards in some ashes, the actual effect of ash will depend on factors like ash loads and the dilution into environmental matrices such as water, soil and sediment. Our approach can serve as an initial methodological standardisation of wildfire ash sampling and chemical analysis protocols.


Assuntos
Incêndios Florestais , Humanos , Ecossistema , Água/análise , Magnésio/análise , Carbono/análise , Nitrogênio , Fatores Socioeconômicos
12.
J Endod ; 49(9): 1169-1175, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37429496

RESUMO

INTRODUCTION: This study evaluated the effects of diabetes mellitus (DM) on the nanostructure of root canal dentin using high-resolution transmission electron microscopy (HRTEM) and inductively coupled plasma mass spectrometry (ICP-MS). METHODS: Twenty extracted human premolars from diabetic and nondiabetic patients (n = 10 in each group) were decoronated and sectioned horizontally into 40 2-mm-thick dentin discs, with each disc designated for a specific test. ICP-MS was used to determine the different elemental levels of copper, lithium, zinc, selenium, strontium, manganese, and magnesium in diabetic and nondiabetic specimens. HRTEM was used to analyze the shape and quantity of the apatite crystals in diabetic and nondiabetic dentin at the nanostructural level. Statistical analysis was performed using Kolmogorov-Smirnov and Student t test (P < .05). RESULTS: ICP-MS revealed significant differences in trace element concentrations between the diabetic and nondiabetic specimens (P < .05), with lower levels of magnesium, zinc, strontium, lithium, manganese, and selenium (P < .05), and higher levels of copper in diabetic specimens (P < .05). HRTEM revealed that diabetic dentin exhibited a less compact structure with smaller crystallites and significantly more crystals in the 2500 nm2 area (P < .05). CONCLUSION: Diabetic dentin exhibited smaller crystallites and altered elemental levels more than nondiabetic dentin, which could explain the higher root canal treatment failure rate in diabetic patients.


Assuntos
Diabetes Mellitus , Selênio , Oligoelementos , Humanos , Magnésio/análise , Magnésio/farmacologia , Cobre/análise , Cobre/farmacologia , Manganês/análise , Manganês/farmacologia , Selênio/análise , Selênio/farmacologia , Cavidade Pulpar , Lítio/análise , Lítio/farmacologia , Oligoelementos/análise , Oligoelementos/farmacologia , Zinco/análise , Zinco/farmacologia , Estrôncio/análise , Estrôncio/farmacologia , Dentina
13.
Molecules ; 28(13)2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37446589

RESUMO

Hydroxyapatite (HA) is a major component of the inorganic minerals in the hard tissues of humans and has been widely used as a biomedical ceramic material in orthopedic and dentistry applications. Because human bone contains several impurities, including carbonates, chlorides, fluorides, magnesium, and strontium, human bone minerals differ from stoichiometric HA. Additionally, natural bone is composed of nano-sized HA, and the nanoscale particles exhibit a high level of biological activity. In this paper, HA is prepared via the hydrothermal process because its reaction conditions are easy to control and it has been shown to be quite feasible for large-scale production. Therefore, the hydrothermal process is an effective and convenient method for the preparation of HA. Furthermore, eggshell is adopted as a source of calcium, and mulberry leaf extract is selectively added to synthesize HA. The eggshell accounts for 11% of the total weight of a whole egg, and it consists of calcium carbonate, calcium phosphate, magnesium carbonate, and organic matter. Eggshell contains a variety of trace elements, such as magnesium and strontium, making the composition of the synthesized HA similar to that of the human skeleton. These trace elements exert considerable benefits for bone growth. Moreover, the use of eggshell as a raw material can permit the recycling of biowaste and a reduction in process costs. The purpose of this study is to prepare HA powder via the hydrothermal method and to explore the effects of hydrothermal conditions on the structure and properties of the synthesized HA. The room-temperature precipitation method is used for the control group. Furthermore, the results of an immersion test in simulated body fluid confirm that the as-prepared HA exhibits good apatite-forming bioactivity, which is an essential requirement for artificial materials to bond to living bones in the living body and promote bone regeneration. In particular, it is confirmed that the HA synthesized with the addition of the mulberry leaf extract exhibits good in vitro biocompatibility. The morphology, crystallite size, and composition of the carbonated nano-HA obtained herein are similar to those of natural bones. The carbonated nano-HA appears to be an excellent material for bioresorbable bone substitutes or drug delivery. Therefore, the nano-HA powder prepared in this study has great potential in biomedical applications.


Assuntos
Durapatita , Oligoelementos , Animais , Humanos , Durapatita/química , Magnésio/análise , Casca de Ovo/química , Oligoelementos/análise , Pós/análise , Materiais Biocompatíveis/química , Carbonatos/química , Estrôncio , Extratos Vegetais/análise
14.
J Anim Sci ; 1012023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37350733

RESUMO

Magnesium oxide (MgO) is one of the most used Mg supplements in livestock. However, to avoid relying upon only one Mg source, it is important to have alternative Mg sources. Therefore, the objective of this study was to evaluate the effects of the interaction of two Mg sources with buffer use on the ruminal microbiota composition, ruminal fermentation, and nutrient digestibility in lactating dairy cows. Twenty lactating Holstein cows were blocked by parity and days in milk into five blocks with four cows each, in a 2 × 2 factorial design. Within blocks, cows were assigned to one of four treatments: 1) MgO; 2) MgO + Na sesquicarbonate (MgO+); 3) calcium-magnesium hydroxide (CaMgOH); 4) CaMgOH + Na sesquicarbonate (CaMgOH+). For 60 d, cows were individually fed a corn silage-based diet, and treatments were top-dressed. Ruminal fluid was collected via an orogastric tube, for analyses of the microbiota composition, volatile fatty acids (VFA), lactate, and ammonia nitrogen (NH3-N). The microbiota composition was analyzed using V4/16S rRNA gene sequencing, and taxonomy was assigned using the Silva database. Statistical analysis was carried out following the procedures of block design analysis, where block and cow were considered random variables. Effects of Mg source, buffer, and the interaction between Mg Source × Buffer were analyzed through orthogonal contrasts. There was no interaction effect of the two factors evaluated. There was a greater concentration of NH3-N, lactate, and butyrate in the ruminal fluid of cows fed with CaMg(OH)2, regardless of the buffer use. The increase in these fermentation intermediates/ end-products can be explained by an increase in abundance of micro-organisms of the genus Prevotella, Lactobacillus, and Butyrivibrio, which are micro-organisms mainly responsible for proteolysis, lactate-production, and butyrate-production in the rumen, respectively. Also, dietary buffer use did not affect the ruminal fermentation metabolites and pH; however, an improvement of the apparent total tract digestibility of dry matter (DM), organic matter (OM), neutral fiber detergent (NDF), and acid fiber detergent (ADF) were found for animals fed with dietary buffer. In summary, there was no interaction effect of buffer use and Mg source, whereas buffer improved total tract apparent digestibility of DM and OM through an increase in NDF and ADF digestibility and CaMg(OH)2 increased ruminal concentration of butyrate and abundance of butyrate-producing bacteria.


Magnesium oxide (MgO) is extensively used as a dietary magnesium (Mg) source in dairy cow diets. However, dairy operations can benefit from other Mg sources. Thus, we evaluated the replacement of dietary MgO with calcium­magnesium hydroxide (CaMg(OH)2) in diets with and without ruminal buffer and their effects on the ruminal microbiota composition, ruminal fermentation, and nutrient digestibility in lactating dairy cows. The study used 20 lactating Holstein cows that were blocked in groups of four and randomly assigned to one of the four treatments. The ruminal content, feed, feces, and urine were collected for analysis of the microbiota composition, ruminal fermentation, nitrogen metabolism, and apparent nutrient digestibility. There was no interaction effect of dietary buffer use and Mg source, while buffer improved total tract apparent digestibility of the dry matter and fiber components; CaMg(OH)2 increased the ruminal concentration of butyrate and the abundance of butyrate-producing bacteria. In summary, we conclude that using CaMg(OH)2 can improve ruminal fermentation regardless of buffer use, which indicates that we can take advantage of the mineral formulation in the diet to modulate the ruminal microbiota composition.


Assuntos
Lactação , Microbiota , Gravidez , Feminino , Bovinos , Animais , Magnésio/análise , Magnésio/metabolismo , Magnésio/farmacologia , Fermentação , Óxido de Magnésio/análise , Óxido de Magnésio/metabolismo , Óxido de Magnésio/farmacologia , Detergentes/análise , Detergentes/metabolismo , Detergentes/farmacologia , RNA Ribossômico 16S/metabolismo , Digestão , Leite/metabolismo , Dieta/veterinária , Butiratos/análise , Zea mays/metabolismo , Lactatos/análise , Lactatos/metabolismo , Lactatos/farmacologia , Rúmen/metabolismo
15.
Lasers Med Sci ; 38(1): 149, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365431

RESUMO

Medicinal plants play a vital role in herbal medical field and allopathic medicine field industry. Chemical and spectroscopic studies of Taraxacum officinale, Hyoscyamus niger, Ajuga bracteosa, Elaeagnus angustifolia, Camellia sinensis, and Berberis lyceum are conducted in this paper by using a 532-nm Nd:YAG laser in an open air environment. These medicinal plant's leaves, roots, seed, and flowers are used to treat a range of diseases by the locals. It is crucial to be able to distinguish between beneficial and detrimental metal elements in these plants. We demonstrated how various elements are categorized and how roots, leaves, seeds and flowers of same plants differ from each other on the basis of elemental analysis. Furthermore, for classification purpose, different classification models, partial least square discriminant analysis (PLS-DA), k-nearest neighbors (kNN), and principal component analysis (PCA) are used. We found silicon (Si), aluminum (Al), iron (Fe), copper (Cu), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), manganese (Mn), phosphorous (P), and vanadium (V) in all of the medicinal plant samples with a molecular form of carbon and nitrogen band. We detected Ca, Mg, Si, and P as primary components in all of the plant samples, as well as V, Fe, Mn, Al, and Ti as essential medicinal metals, and additional trace elements like Si, Sr, and Al. The result's findings show that the PLS-DA classification model with single normal variate (SNV) preprocessing method is the most effective classification model for different types of plant samples. The average correct classification rate obtained for PLS-DA with SNV is 95%. Moreover, laser-induced breakdown spectroscopy (LIBS) was successfully employed to perform rapid, sensitive, and quantitative trace element analysis on medicinal herbs and plant samples.


Assuntos
Lasers de Estado Sólido , Plantas Medicinais , Oligoelementos , Plantas Medicinais/química , Quimiometria , Análise Espectral/métodos , Oligoelementos/análise , Magnésio/análise , Magnésio/química , Cálcio/análise , Sódio
16.
Environ Pollut ; 332: 121968, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37290633

RESUMO

Reducing the bioavailability of both cadmium (Cd) and arsenic (As) in paddy fields is a worldwide challenge. The authors investigated whether ridge cultivation combined with biochar or calcium-magnesium-phosphorus (CMP) fertilizer effectively reduces the accumulation of Cd and As in rice grains. Field trial showed that applying biochar or CMP on the ridges was similar to the continuous flooding, which maintained grain Cd at a low level, but grain As was reduced by 55.6%, 46.8% (IIyou28) and 61.9%, 59.3% (Ruiyou 399). Compared with ridging alone, the application of biochar or CMP decreased grain Cd by 38.7%, 37.8% (IIyou28) and 67.58%, 60.98% (Ruiyou399), and reduced grain As by 38.9%, 26.9% (IIyou28) and 39.7%, 35.5% (Ruiyou 399). Microcosm experiment showed that applying biochar and CMP on the ridges decreased As in soil solution by 75.6% and 82.5%, respectively, and kept Cd at a comparably low level at 0.13-0.15 µg L-1. Aggregated boosted tree (ABT) analysis revealed that ridge cultivation combined with soil amendments altered soil pH, redox state (Eh) and enhanced the interaction of Ca, Fe, Mn with As and Cd, which promoted the concerted reduction of As and Cd bioavailability. Application of biochar on the ridges enhanced the effects of Ca and Mn to maintain a low level of Cd, and enhanced the effects of pH to reduce As in soil solution. Similar to ridging alone, applying CMP on the ridges enhanced the effects of Mn to reduce As in soil solution, and enhanced the effects of pH and Mn to maintain Cd at a low level. Ridging also promoted the association of As with poorly/well-crystalline Fe/Al and the association of Cd on Mn-oxides. This study provides an effective and environmentally friendly method to decrease Cd and As bioavailability in paddy fields and mitigate Cd and As accumulation in rice grain.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Cádmio/análise , Arsênio/análise , Fertilizantes/análise , Cálcio/análise , Magnésio/análise , Solo/química , Poluentes do Solo/análise , Carvão Vegetal/química , Ecossistema , Fósforo
17.
Chem Biodivers ; 20(6): e202201093, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37114879

RESUMO

Due to their distinct characteristics and possible uses in a variety of disciplines, nanoparticles have attracted a lot of attention recently. One area of interest is the synthesis of nanoparticles using natural sources such as bee pollen. The research aims to evaluate the usability of bee pollen extract-based magnesium nanoparticles (MgNPs). First, a palynological study was used to determine the plant source of bee pollen. The nanoparticle was characterized using scanning electron microscopy, energy dispersive X-ray analysis, transmission electron microscopy, X-ray diffractometry, and Fourier transform infrared spectroscopy. The results revealed cubic-shaped MgNPs with an average size range of 36-40 nm. Afterward, nanoparticles were evaluated for their antioxidant, antimicrobial, and neurotoxic properties. It was determined that the total antioxidant capacity, phenolic (TPC), flavonoid (TFC) content, DPPH radical scavenging, and antimicrobial activity of the nanoparticles were lower than pollen extract. At the same time, nanoparticles have less toxicity than bee pollen.


Assuntos
Anti-Infecciosos , Nanopartículas , Neuroblastoma , Animais , Humanos , Abelhas , Antioxidantes/farmacologia , Antioxidantes/análise , Magnésio/análise , Extratos Vegetais/farmacologia , Extratos Vegetais/análise , Anti-Infecciosos/farmacologia , Anti-Infecciosos/análise , Nanopartículas/química , Linhagem Celular , Pólen/química , Espectroscopia de Infravermelho com Transformada de Fourier
18.
ACS Biomater Sci Eng ; 9(5): 2376-2391, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37071118

RESUMO

Currently, permanent vascular stents are fabricated using titanium and stainless steel implants that are nondegradable and offer high stability, but they have certain disadvantages. For example, the prolonged exposition of aggressive ions in the physiological media and the existence of defects in the oxide film create conditions for corrosion to occur, thus triggering unwanted biological events and compromising the mechanical integrity of the implants. Moreover, when the implant does not need to be permanent, there is the need to submit the patient for a second surgery for implant removal. As a solution for nonpermanent implants, biodegradable magnesium alloys have been deemed a promising substitute, for example, for cardiovascular-related applications and the construction of orthopedic devices. A biodegradable magnesium alloy (Mg-2.5Zn) reinforced by zinc and eggshell was employed in this study as an environment-conscious magnesium (eco) composite (Mg-2.5Zn-xES). Disintegrated melt deposition (DMD) was used to fabricate the composite. Experimental studies were conducted to investigate the biodegradation performance of Mg-Zn alloys containing 3 and 7 wt % eggshell (ES) in simulated body fluid (SBF) at 37 °C. Different corrosion techniques were used to study the corrosion behavior of the Mg-2.5Zn-xES composites, including weight loss measurements, hydrogen evolution, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and scanning vibrating electrode technique (SVET). Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) were employed to scrutinize the corroded surfaces' morphology and composition. The outcomes indicated that Mg-2.5Zn-3ES possesses the lowest degradation activity.


Assuntos
Ligas , Líquidos Corporais , Animais , Humanos , Ligas/química , Magnésio/análise , Magnésio/química , Casca de Ovo , Próteses e Implantes , Líquidos Corporais/química
19.
Environ Sci Pollut Res Int ; 30(22): 62653-62674, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36947380

RESUMO

Groundwater is a naturally occurring potential source for drinking, irrigation, agricultural and industrial purposes. The population growth and accelerated development of industries and agriculture activity degrade groundwater quality. The groundwater quality of an area was determined by the physical and chemical parameters, influenced by geology, soil, land use, land cover and anthropogenic activities. Perambalur district in Tamil Nadu has been selected as a study area with a total geographical area of around 1757 km2. In the study area, groundwater quality decreases due to the usage of chemical fertilisers and pesticides in agricultural land and mining activities. So, the hydrogeochemical assessment will help to determine the groundwater suitability for drinking. Forty-eight groundwater samples were collected from the study area during the pre-monsoon (July 2021) and post-monsoon season (January 2022). Samples were analysed using the standard methods prescribed by the American Public Health Association for pH, electrical conductivity (EC), total dissolved solids (TDS), calcium, magnesium, sodium, potassium, carbonate, bicarbonate, chloride, sulphate, nitrate and fluoride. The spatial distribution of major physiochemical parameters is mapped using the inverse distance weighted (IDW) interpolation technique. The evaluation of hydrochemical facies from piper plots revealed that the major cation and anion were in the order of Ca2+ > Mg2+ > Na+ > K+ and Cl- > HCO3- > SO42- > NO3- in both seasons, respectively. Further, the plot explains the presence of both permanent and temporary hardness in the groundwater. The evaluation of hydrochemical facies from the piper plot emphasises that the reverse ion exchange controls groundwater chemistry. The assessment of chloro-alkaline indices reveals that the sodium and potassium in groundwater get substituted with magnesium and calcium in the parent rock, which determines the groundwater composition. The values of saturation indices reveal that calcite and dolomite are supersaturated and tend to precipitate. From principal component analysis, the principal components have an eigenvalue of more than 1, containing 79.8% and 79.2% in the total variance in pre-monsoon and post-monsoon, respectively. Most physiochemical parameters like TDS, EC, Na+, Mg2+, Cl- and SO42 - have strong positive loading and are responsible for the changes in groundwater chemistry. Finally, the calculation of the water quality index identified that groundwater quality in post-monsoon tends to decline compared to pre-monsoon.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Humanos , Magnésio/análise , Monitoramento Ambiental/métodos , Cálcio/análise , Índia , Facies , Poluentes Químicos da Água/análise , Água Subterrânea/química , Qualidade da Água , Sódio/análise
20.
Zygote ; 31(3): 246-252, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36919850

RESUMO

This study is a comparative analysis of the biochemical, hormonal, and mineral compositions of follicular fluid in preovulatory and cystic follicles of water buffalo (Bubalus bubalis). In total, reproductive tracts from 215 buffalo along with intact ovaries were collected randomly from an abattoir. The incidence of cystic conditions found in this study was 3.72% (8/215), involving the right ovary in 62.5% of instances and the left ovary in 37.5% of instances during the non-breeding season. Follicular fluid was aspirated from preovulatory follicles (12-15 mm diameter, oestrogen-active, follicular phase or stage IV corpus luteum on one of the two ovaries, n = 10) and cystic follicles (at least 20 mm diameter, no corpus luteum on any one of the two ovaries, n = 8). The follicular fluid samples were assayed for biochemical components (uric acid, creatinine, blood urea nitrogen, cholesterol, total protein, glucose, ascorbic acid, and alkaline phosphatase), hormones (progesterone, estradiol, and insulin), and minerals (calcium, magnesium, phosphorus, copper, zinc, and cobalt). Cystic follicles had greater (P < 0.05) concentrations of creatinine, blood urea nitrogen, cholesterol, progesterone, copper, zinc, and cobalt, and lesser (P < 0.05) concentrations of uric acid, glucose, ascorbic acid, estradiol, insulin, calcium, magnesium, and phosphorus compared with preovulatory follicles. These results indicated the marked differences in follicular fluid composition between preovulatory and cystic follicles in buffalo. Some of the changes were indicative of oxidative stress and disturbed steroidogenesis, two important mechanisms shown to be associated with cystic ovarian disease in various species. Further studies are warranted to investigate whether these differences are directly or indirectly involved in the formation of cystic follicles or are mere manifestations of the condition.


Assuntos
Búfalos , Folículo Ovariano , Animais , Feminino , Folículo Ovariano/metabolismo , Búfalos/metabolismo , Progesterona/metabolismo , Cálcio/metabolismo , Cobre , Magnésio/análise , Magnésio/metabolismo , Estações do Ano , Creatinina/análise , Creatinina/metabolismo , Ácido Úrico/análise , Ácido Úrico/metabolismo , Líquido Folicular/metabolismo , Estradiol/metabolismo , Insulina/análise , Insulina/metabolismo , Colesterol/análise , Colesterol/metabolismo , Minerais/análise , Minerais/metabolismo , Ácido Ascórbico , Zinco , Glucose , Cobalto/análise , Cobalto/metabolismo , Fósforo/análise , Fósforo/metabolismo
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