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1.
Food Res Int ; 187: 114329, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763632

RESUMO

The utilization of non-animal-derived materials to imitate cartilage is critical for the advancement of plant-based simulated meat. In this study, gellan gum (GG), konjac glucomannan (KGM), and wheat fiber (WF) were used to construct hydrogel, and the mechanical strength, water properties, and microstructure were regulated by constructing Ca2+ cross-links and moisture control. The hardness, chewiness, resilience, shear force, and shear energy of the Ca2+ cross-linked samples were significantly improved. Extrusion dehydration further changes the related mechanical properties of the hydrogel and results in a tighter microstructure. The findings suggest that the establishment of Ca2+ cross-links and water regulation are efficacious techniques for modifying the texture of the GG/KGM/WF composite hydrogel. Correlation analysis and sensory evaluation showed that the test indexes and sensory scores of the samples with Ca2+ crosslinking and 80 % moisture content were similar to chicken breast cartilage, and the samples with Ca2+ crosslinking and 70 % moisture content were similar to pig crescent bone. This study presents a framework for designing edible cartilage simulators using polysaccharide hydrogels, with implications for enhancing the resemblance of plant-based meat products to real meat and expanding the range of vegetarian offerings available.


Assuntos
Hidrogéis , Mananas , Polissacarídeos Bacterianos , Triticum , Polissacarídeos Bacterianos/química , Mananas/química , Animais , Hidrogéis/química , Triticum/química , Cartilagem/química , Água/química , Reagentes de Ligações Cruzadas/química , Galinhas , Cálcio/análise , Cálcio/química , Fibras na Dieta/análise
2.
BMC Oral Health ; 24(1): 581, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38764034

RESUMO

BACKGROUND: This study was conducted to compare chemical, elemental and surface properties of sound and carious dentin after application of two restorative materials resin-modified glassionomer claimed to be bioactive and glass hybrid restorative material after enzymatic chemomechanical caries removal (CMCR) agent. METHODS: Forty carious and twenty non-carious human permanent molars were used. Molars were randomly distributed into three main groups: Group 1 (negative control) - sound molars, Group 2 (positive control) - molars were left without caries removal and Group 3 (Test Group) caries excavated with enzymatic based CMCR agent. After caries excavation and restoration application, all specimens were prepared Vickers microhardness test (VHN), for elemental analysis using Energy Dispersive Xray (EDX) mapping and finally chemical analysis using Micro-Raman microscopy. RESULTS: Vickers microhardness values of dentin with the claimed bioactive GIC specimens was statistically higher than with glass hybrid GIC specimens. EDX analysis at the junction estimated: Calcium and Phosphorus of the glass hybrid GIC showed insignificantly higher mean valued than that of the bioactive GIC. Silica and Aluminum mean values at the junction were significantly higher with bioactive GIC specimens than glass hybrid GIC specimen. Micro-raman spectroscopy revealed that bioactive GIC specimens showed higher frequencies of v 1 PO 4, which indicated high level of remineralization. CONCLUSIONS: It was concluded that ion-releasing bioactive resin-based restorative material had increased the microhardness and remineralization rate of carries affected and sound dentin. In addition, enzymatic caries excavation with papain-based CMCR agent has no adverse effect on dentin substrate.


Assuntos
Cárie Dentária , Preparo da Cavidade Dentária , Dentina , Cimentos de Ionômeros de Vidro , Dureza , Humanos , Cárie Dentária/terapia , Cimentos de Ionômeros de Vidro/química , Preparo da Cavidade Dentária/métodos , Fósforo/análise , Papaína/uso terapêutico , Propriedades de Superfície , Restauração Dentária Permanente/métodos , Espectrometria por Raios X , Análise Espectral Raman , Cálcio/análise , Dente Molar , Remineralização Dentária/métodos , Alumínio , Dióxido de Silício , Teste de Materiais
3.
Nutrients ; 16(9)2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38732636

RESUMO

(1) Background: parenteral nutrition (PN) is indispensable for patients unable to receive oral or enteral feeding. However, the complexity of PN solutions presents challenges regarding stability and compatibility. Precipitation reactions may occur. The most frequent is the formation of calcium phosphate (Ca-P). The different factors influencing these reactions must be considered to ensure patient safety. (2) Methods: eight paediatric PN solutions were prepared, following standard protocols. Samples were stored at room temperature and in a refrigerator. Electron microscopy, coupled with energy dispersive X-ray spectroscopy (EDS), was employed. Precipitates were analysed for composition and morphology. (3) Results: precipitates were observed in all samples, even at day 0. Crystalline structures, predominantly composed of calcium or magnesium, sometimes associated with chlorine or phosphorus, were detected. Additionally, amorphous precipitates, contained heterogeneous compositions, including unexpected elements, were identified. (4) Conclusions: various precipitates, primarily calcium- or magnesium-based, can form in PN solutions, although it is not expected that they can form under the real conditions of use. Calcium oxalate precipitation has been characterised, but the use of organic calcium and phosphate salts appears to mitigate calcium phosphate precipitation. Electron microscopy provides interesting results on NP precipitation, but sample preparation may present technical limitations that affect the interpretation of the results.


Assuntos
Fosfatos de Cálcio , Precipitação Química , Estabilidade de Medicamentos , Soluções de Nutrição Parenteral , Soluções de Nutrição Parenteral/química , Fosfatos de Cálcio/química , Humanos , Nutrição Parenteral , Espectrometria por Raios X , Microscopia Eletrônica , Magnésio/química , Cálcio/química , Cálcio/análise
4.
J Clin Pediatr Dent ; 48(3): 86-93, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38755986

RESUMO

The aim of the study was to evaluate the severity of molar incisor hypomineralisation (MIH), related oral health and investigate salivary mineral composition. The study was conducted with 50 participants aged between 6-15 years who were effected with MIH and 50 without MIH. The International Caries Detection and Assessment System (ICDAS) scores, Decayed, Missing, Filled Teeth/Surface (DMFT/S), dft/s and gingival/plaque indices were evaluated. The pH, flow rate, buffering capacity and mineral composition of saliva was measured. "Student t" test, one-way analysis of variance in repeated measurements of groups, and Tukey multiplex in subgroup comparisons was used. Kruskal-Wallis, Mann-Whitney U, Wilcoxon and chi-square tests were used to analyze qualitative data and compare groups. A total of 100 children (57 females 43 males, mean age 10.12 ± 1.85) participated in the study. There was no difference between ICDAS, DMFT/S scores, but dft/s index values were statistically significant (p = 0.001). The simplified oral hygiene index of MIH patients were statistically higher, but no significant differences were found in modified gingival indices (p = 0.52). Although the salivary pH and flow rate of the patients in the study group were lower, the buffering capacity was higher than those in the control group, but no significant difference was observed (p = 0.64). The mean values of phosphorus, carbon and calcium content in the saliva samples of MIH patients were higher than those of patients without MIH, and this difference was low for phosphorus (p = 0.76) and carbon (p = 0.74), but significantly higher for calcium. To the best of our knowledge, this is the first study to evaluate the association between calcium, phosphate and carbon levels in saliva of children with MIH. The significantly high amount of calcium in the saliva of patients with MIH suggests that further investigations are needed.


Assuntos
Hipoplasia do Esmalte Dentário , Saliva , Humanos , Saliva/química , Criança , Feminino , Masculino , Adolescente , Concentração de Íons de Hidrogênio , Minerais/análise , Cálcio/análise , Índice CPO , Índice de Gravidade de Doença , Fósforo/análise , Hipomineralização Molar
5.
ACS Nano ; 18(20): 12808-12819, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38717026

RESUMO

Considerable progress has already been made in sweat sensors based on electrochemical methods to realize real-time monitoring of biomarkers. However, realizing long-term monitoring of multiple targets at the atomic level remains extremely challenging, in terms of designing stable solid contact (SC) interfaces and fully integrating multiple modules for large-scale applications of sweat sensors. Herein, a fully integrated wristwatch was designed using mass-manufactured sensor arrays based on hierarchical multilayer-pore cross-linked N-doped porous carbon coated by reduced graphene oxide (NPCs@rGO-950) microspheres with high hydrophobicity as core SC, and highly selective monitoring simultaneously for K+, Na+, and Ca2+ ions in human sweat was achieved, exhibiting near-Nernst responses almost without forming an interfacial water layer. Combined with computed tomography, solid-solid interface potential diffusion simulation results reveal extremely low interface diffusion potential and high interface capacitance (598 µF), ensuring the excellent potential stability, reversibility, repeatability, and selectivity of sensor arrays. The developed highly integrated-multiplexed wristwatch with multiple modules, including SC, sensor array, microfluidic chip, signal transduction, signal processing, and data visualization, achieved reliable real-time monitoring for K+, Na+, and Ca2+ ion concentrations in sweat. Ingenious material design, scalable sensor fabrication, and electrical integration of multimodule wearables lay the foundation for developing reliable sweat-sensing systems for health monitoring.


Assuntos
Eletrólitos , Grafite , Suor , Dispositivos Eletrônicos Vestíveis , Suor/química , Humanos , Grafite/química , Eletrólitos/química , Íons/análise , Cálcio/análise , Sódio/análise , Sódio/química , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Potássio/análise
6.
Reprod Domest Anim ; 59(5): e14569, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38715435

RESUMO

The effects of an aqueous extract of Scabiosa atropurpurea L. (AES) on the reproduction potential of Queue Fine de l'Ouest rams were evaluated over 9 weeks. Eighteen mature (4-6 years old) rams (52.8 ± 2.6 kg) were divided into three groups. The control (C) group was fed oat hay ad libitum with 700 g of concentrate and the other two groups were fed the same diet supplemented with AES at 1 and 2 mg/kg body weight (AES1 and AES2, respectively). Ram sperm was collected with an artificial vagina (2 × 2 days/week) to evaluate sperm production and quality, antioxidant activity, the adenosine triphosphate (ATP) and calcium concentrations. Sexual behaviour and plasma testosterone concentrations were also investigated. The administration of AES improved sexual behaviour (the duration of contact and the number of lateral approaches). The addition of AES also improved individual spermatozoa motility (C: 71.7% ± 6.3%; AES1: 78.3% ± 4.9%; AES2: 83.8% ± 4.4%), the sperm concentration (C: 5.6 ± 0.36; AES1: 6.4 ± 0.81; AES2: 6.7 ± 0.52 × 109 spermatozoa/mL), the ATP ratio (C: 1 ± 0.08; AES1: 2.1 ± 0.08; AES2: 3.3 ± 0.08) and the calcium concentration (C: 5.6 ± 0.24; AES1: 7.7 ± 0.21; AES2: 8.1 ± 0.24 mmol/L). AES treatment decreased the percentage of abnormal sperm (C: 18.5% ± 1.2%; AES1: 16.2% ± 1.1%; AES2: 14.8% ± 0.94%) and DNA damage (C: 62%; AES1: 27%; AES2: 33%) and was associated with elevated seminal fluid antioxidant activity (C: 22 ± 0.27; AES1: 27.1 ± 1.08 and AES2: 27.5 ± 0.36 mmol Trolox equivalents/L) and plasma testosterone (C: 8.3 ± 0.7; AES1: 11.7 ± 0.4; AES2: 15 ± 0.7 ng/L). In conclusion, our study suggests that S. atropurpurea may be potentially useful to enhance libido and sperm production and quality in ram.


Assuntos
Extratos Vegetais , Comportamento Sexual Animal , Espermatozoides , Masculino , Animais , Espermatozoides/efeitos dos fármacos , Comportamento Sexual Animal/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/administração & dosagem , Testosterona/sangue , Análise do Sêmen/veterinária , Motilidade dos Espermatozoides/efeitos dos fármacos , Suplementos Nutricionais , Antioxidantes/farmacologia , Dieta/veterinária , Contagem de Espermatozoides , Cálcio/análise , Cálcio/sangue , Carneiro Doméstico , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/análise
7.
Wiad Lek ; 77(3): 424-428, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38691782

RESUMO

OBJECTIVE: Aim: To prove an independence of CAC score comparatively to conventional risk factors such as age, and dyslipidemia especially in patients under forty years of age. PATIENTS AND METHODS: Materials and Methods: Thirty-four asymptomatic adult patients with no prior established atherosclerotic cardiovascular disease, diabetes mellitus or severe comorbidities, except of complex clinical examination, underwent CT scan with evaluation of coronary artery calcium score. RESULTS: Results: The average total cholesterol level in the group was (5.62±1.02) mmol/l, indicating the presence of dyslipidemia. The average HDL level was (1.26±0.24) mmol/l, suggesting an average risk of atherosclerosis. The average LDL levels were within the borderline range at (3.63±1.01) mmol/l. The average triglyceride level was within the safe range at (1.93±1.08) mmol/l. The atherogenicity coefficient indicated a moderate risk of atherosclerosis with an average value of 3.64±1.31. The average coronary artery calcium score was 56.71±143.85, indicating minor plaques and a moderate risk of coronary artery disease. Correlation analysis revealed no significant correlation between age and the CAC score (r=0.1, p>0.05). However, reliable direct correlation of weak strength was found between the CAC score and LDL level (r=0.35, p<0.05). Direct correlations of weak strength were also observed between age and the levels of total cholesterol, LDL and the atherogenicity coefficient (r=0.43, 0.49, 0.42 respectively, p<0.05). CONCLUSION: Conclusions: Coronary artery calcium score is a valuable screening tool for identifying potential obstructive coronary artery disease, not only for individuals aged forty and above, but also for younger asymptomatic patients.


Assuntos
Doença da Artéria Coronariana , Humanos , Masculino , Feminino , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/metabolismo , Adulto , Pessoa de Meia-Idade , Fatores de Risco , Vasos Coronários/metabolismo , Vasos Coronários/diagnóstico por imagem , Cálcio/metabolismo , Cálcio/análise , Tomografia Computadorizada por Raios X , Idoso
8.
J Dent ; 145: 104997, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38621525

RESUMO

OBJECTIVE: To assess the effects of arginine, with or without sodium fluoride (NaF; 1,450 ppm), on saliva-derived microcosm biofilms and enamel demineralization. METHODS: Saliva-derived biofilms were grown on bovine enamel blocks in 0.2 % sucrose-containing modified McBain medium, according to six experimental groups: control (McBain 0.2 %); 2.5 % arginine; 8 % arginine; NaF; 2.5 % arginine with NaF; and 8 % arginine with NaF. After 5 days of growth, biofilm viability was assessed by colony-forming units counting, laser scanning confocal microscopy was used to determine biofilm vitality and extracellular polysaccharide (EPS) production, while biofilm metabolism was evaluated using the resazurin assay and lactic acid quantification. Demineralization was evaluated by measuring pH in the culture medium and calcium release. Data were analyzed by Kruskal-Wallis' and Dunn's tests (p < 0.05). RESULTS: 8 % arginine with NaF showed the strongest reduction in total streptococci and total microorganism counts, with no significant difference compared to arginine without NaF. Neither 2.5 % arginine alone nor NaF alone significantly reduced microbial counts compared to the control, although in combination, a reduction in all microbial groups was observed. Similar trends were found for biofilm vitality and EPS, and calcium released to the growth medium. CONCLUSIONS: 8 % Arginine, with or without NaF, exhibited the strongest antimicrobial activity and reduced enamel calcium loss. Also, NaF enhanced the effects of 2.5 % arginine, yielding similar results to 8 % arginine for most parameters analyzed. CLINICAL SIGNIFICANCE: The results provided further evidence on how arginine, with or without NaF, affects oral microcosm biofilms and enamel mineral loss.


Assuntos
Arginina , Biofilmes , Cariostáticos , Esmalte Dentário , Microscopia Confocal , Saliva , Fluoreto de Sódio , Desmineralização do Dente , Biofilmes/efeitos dos fármacos , Arginina/farmacologia , Fluoreto de Sódio/farmacologia , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/microbiologia , Bovinos , Animais , Desmineralização do Dente/prevenção & controle , Desmineralização do Dente/microbiologia , Cariostáticos/farmacologia , Saliva/microbiologia , Saliva/metabolismo , Saliva/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Viabilidade Microbiana/efeitos dos fármacos , Cálcio/análise , Cálcio/metabolismo , Streptococcus/efeitos dos fármacos , Xantenos/farmacologia , Contagem de Colônia Microbiana , Oxazinas/farmacologia
9.
ACS Sens ; 9(4): 1622-1643, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38587931

RESUMO

Genetically encoded fluorescent metal ion sensors are powerful tools for elucidating metal dynamics in living systems. Over the last 25 years since the first examples of genetically encoded fluorescent protein-based calcium indicators, this toolbox of probes has expanded to include other essential and non-essential metal ions. Collectively, these tools have illuminated fundamental aspects of metal homeostasis and trafficking that are crucial to fields ranging from neurobiology to human nutrition. Despite these advances, much of the application of metal ion sensors remains limited to mammalian cells and tissues and a limited number of essential metals. Applications beyond mammalian systems and in vivo applications in living organisms have primarily used genetically encoded calcium ion sensors. The aim of this Perspective is to provide, with the support of historical and recent literature, an updated and critical view of the design and use of fluorescent protein-based sensors for detecting essential metal ions in various organisms. We highlight the historical progress and achievements with calcium sensors and discuss more recent advances and opportunities for the detection of other essential metal ions. We also discuss outstanding challenges in the field and directions for future studies, including detecting a wider variety of metal ions, developing and implementing a broader spectral range of sensors for multiplexing experiments, and applying sensors to a wider range of single- and multi-species biological systems.


Assuntos
Proteínas Luminescentes , Metais , Humanos , Metais/química , Proteínas Luminescentes/química , Animais , Cálcio/análise , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Íons/química , Íons/análise
10.
Clin Chim Acta ; 558: 119667, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38583551

RESUMO

BACKGROUND AND OBJECTIVES: We assessed properties of running averages for our hospital's most common chemistry analytes, for use in real-time patient-based quality control (PBQC). We determined whether there was dependence of any running averages on 24-h clock time (time-of-day, TOD). MATERIALS AND METHODS: We analyzed 3-months' data for measurements of 13 metabolic panel components. Running averages for 20 consecutive results (20-mers) were computed for data restricted to results within reference intervals. This produced an overall mean (X) and standard-deviation (SD) of 20-mers for each analyte. We then computed the average 20-mer result (Y) reported within 1-h bins across 24-hour clock time (t). Y(t) was regarded as having TOD-dependence if either nadir or apex values for |Y-X| exceeded 0.5 SD, occurring within a contiguous series of at least 4 Y(t) values on one side of the mean. RESULTS: Seven analytes (albumin, aspartate aminotransferase, calcium, chloride, CO2, potassium, total protein) demonstrated TOD-dependence of running means for 20-mers. CONCLUSIONS: At our hospital, TOD-dependence of running means was identified for 7 of 13 metabolic panel analytes. TOD-dependence is likely to be hospital-specific. Utilization of TOD-dependent targets for PBQC, rather than fixed targets, would be appropriate in these cases.


Assuntos
Controle de Qualidade , Humanos , Fatores de Tempo , Hospitais , Potássio/análise , Cálcio/metabolismo , Cálcio/análise , Aspartato Aminotransferases/sangue , Aspartato Aminotransferases/metabolismo , Aspartato Aminotransferases/análise , Análise Química do Sangue/normas
11.
Anal Chim Acta ; 1305: 342590, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38677844

RESUMO

Monitoring extracellular calcium ion (Ca2+) chemical signals in neurons is crucial for tracking physiological and pathological changes associated with brain diseases in live animals. Potentiometry based solid-state ion-selective electrodes (ISEs) with the assist of functional carbon nanomaterials as ideal solid-contact layer could realize the potential response for in vitro and in vivo analysis. Herein, we employ a kind of biomass derived porous carbon as a transducing layer to prompt efficient ion to electron transduction while stabilizes the potential drift. The eco-friendly porous carbon after activation (APB) displays a high specific area with inherit macropores, micropores, and large specific capacitance. When employed as transducer in ISEs, a stable potential response, minimized potential drift can be obtained. Benefiting from these excellent properties, a solid-state Ca2+ selective carbon fiber electrodes (CFEs) with a sandwich structure is constructed and employed for real time sensing of Ca2+ under electrical stimulation. This study presents a new approach to develop sustainable and versatile transducers in solid-state ISEs, a crucial way for in vivo sensing.


Assuntos
Cálcio , Carbono , Nanoestruturas , Cálcio/química , Cálcio/análise , Carbono/química , Nanoestruturas/química , Eletrodos Seletivos de Íons , Animais , Porosidade , Transdutores , Técnicas Eletroquímicas/instrumentação
12.
Nature ; 628(8009): 795-803, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38632396

RESUMO

Insects constitute the most species-rich radiation of metazoa, a success that is due to the evolution of active flight. Unlike pterosaurs, birds and bats, the wings of insects did not evolve from legs1, but are novel structures that are attached to the body via a biomechanically complex hinge that transforms tiny, high-frequency oscillations of specialized power muscles into the sweeping back-and-forth motion of the wings2. The hinge consists of a system of tiny, hardened structures called sclerites that are interconnected to one another via flexible joints and regulated by the activity of specialized control muscles. Here we imaged the activity of these muscles in a fly using a genetically encoded calcium indicator, while simultaneously tracking the three-dimensional motion of the wings with high-speed cameras. Using machine learning, we created a convolutional neural network3 that accurately predicts wing motion from the activity of the steering muscles, and an encoder-decoder4 that predicts the role of the individual sclerites on wing motion. By replaying patterns of wing motion on a dynamically scaled robotic fly, we quantified the effects of steering muscle activity on aerodynamic forces. A physics-based simulation incorporating our hinge model generates flight manoeuvres that are remarkably similar to those of free-flying flies. This integrative, multi-disciplinary approach reveals the mechanical control logic of the insect wing hinge, arguably among the most sophisticated and evolutionarily important skeletal structures in the natural world.


Assuntos
Drosophila melanogaster , Voo Animal , Aprendizado de Máquina , Asas de Animais , Animais , Feminino , Fenômenos Biomecânicos/fisiologia , Drosophila melanogaster/fisiologia , Drosophila melanogaster/anatomia & histologia , Voo Animal/fisiologia , Músculos/fisiologia , Músculos/anatomia & histologia , Redes Neurais de Computação , Robótica , Asas de Animais/fisiologia , Asas de Animais/anatomia & histologia , Movimento/fisiologia , Cálcio/análise , Cálcio/metabolismo
13.
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
14.
Environ Sci Pollut Res Int ; 31(19): 28166-28177, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38532210

RESUMO

Taihu Lake, the third largest freshwater lake in China, has experienced rapid salinization in the past decades; however, little is known about the impact of sodium (Na) on ion exchange in the lake environment. To explore the potential effect of increased Na on the migration of base cations (Ca and Mg) and resulting redistribution between the water and sediment, we used the adsorption-exchange experiment, MINTEQ modeling to explore the cation exchange induced by high Na input, and its impact on the redistribution of Ca and Mg in Taihu different media. The results indicated that exchanged quantity of Ca and Mg increased with time, and the exchange process reached 90% during 0-4 h and reached equilibrium after 24 h under 100 mg/L Na (the maximum Na concentration in Taihu sediment pore water). Our MINTEQ modeled result indicated that the exchanged quantity of Ca and Mg increased with the increasing Na concentration, with Ca being preferably exchanged over Mg at the same Na concentration. The MINTEQ model further predicted that, in the Taihu lake environment, the exchange adsorption would reach the equilibrium at the concentration of 6000 mg/L Na, with exchanged Ca2+ and Mg2+ accounting for 47% and 55% of the total exchangeable Ca and Mg in the sediment, respectively. Although current Na-induced exchange in the Taihu lake has been far from the equilibrium, the MINTEQ result confirmed the existence of this reaction and predicted the potential redistribution of base cations or Ca/Mg ratio in the lake sediment and water phase with further Na increase. Furthermore, our field observations not only confirmed the existence of Na-induced cation exchange in this lake environment but also were generally in agreement with our experimental and modeled results. The increased salinization-induced ion exchange would alter the re-distribution of base cations and the resulting potential ecosystem consequences should be given close attention in this large freshwater lake.


Assuntos
Monitoramento Ambiental , Lagos , Modelos Teóricos , China , Lagos/química , Salinidade , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Sódio/análise , Sódio/química , Troca Iônica , Cálcio/análise , Cálcio/química , Magnésio/análise , Magnésio/química , Cátions/química
15.
Chembiochem ; 25(10): e202400009, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38545627

RESUMO

Calcium (Ca2+) ions play a crucial role in the functioning of neurons, governing various aspects of neuronal activity such as rapid modulation and alterations in gene expression. Ca2+ signaling has a significant impact on the development of diseases and the impairment of neuronal functions. Herein, the study reports a Ca2+ ion sensor in neuronal cells using a gold nanorod. The gold nanorod (GA-GNR) conjugated glutamic acid developed in the study was used as a nano-bio probe for the experimental and in vitro detection of calcium. The nanosensor is colloidally stable, preserves plasmonic properties, and shows good viability in neuronal cells, as well as promoting neuron cell line growth. The cytotoxicity and cell penetration of the nanosensor are studied using Raman spectroscopy, brightfield and darkfield microscopy imaging, and MTT assays. The quantification of Ca2+ ions in neuronal cells is determined by monitoring the surface plasmon resonance (SPR) of the GA-GNR. The change in the intensity profile in the presence of Ca2+ incubated neurons was effectively used to develop a portable prototype of an optical Ca2+ sensor, proposing it as a tool for neurodegenerative disease diagnosis and neuromodulation evaluation.


Assuntos
Cálcio , Ácido Glutâmico , Ouro , Nanotubos , Neurônios , Ouro/química , Cálcio/metabolismo , Cálcio/análise , Neurônios/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Nanotubos/química , Ácido Glutâmico/análise , Ressonância de Plasmônio de Superfície , Animais , Técnicas Biossensoriais , Humanos , Íons/análise , Íons/química , Sobrevivência Celular/efeitos dos fármacos
16.
Cancer Sci ; 115(5): 1446-1458, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38438247

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) patients have late presentation at the time of diagnosis and a poor prognosis. Metal dyshomeostasis is known to play a role in cancer progression. However, the blood and tissue metallome of PDAC patients has not been assessed. This study aimed to determine the levels of essential and toxic metals in the serum and pancreatic tissue from PDAC patients. Serum samples were obtained from PDAC patients before surgical resection. Tissue (tumor and adjacent normal pancreas) were obtained from the surgically resected specimen. Inductively coupled plasma-mass spectrometry (ICP-MS) analysis was performed to quantify the levels of 10 essential and 3 toxic metals in these samples. Statistical analysis was performed to identify dysregulated metals in PDAC and their role as potential diagnostic and prognostic biomarkers. Significantly decreased serum levels of magnesium, potassium, calcium, iron, zinc, selenium, arsenic, and mercury and increased levels of molybdenum were shown to be associated with PDAC. There were significantly decreased levels of zinc, manganese and molybdenum, and increased levels of calcium and selenium in the pancreatic tumor tissue compared with the adjacent normal pancreas. Notably, lower serum levels of calcium, iron, and selenium, and higher levels of manganese, were significantly associated with a poor prognosis (i.e., overall survival) in PDAC patients. In conclusion, this is the first study to comprehensively assess the serum and tissue metallome of PDAC patients. It identified the association of metals with PDAC diagnosis and prognosis.


Assuntos
Biomarcadores Tumorais , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/sangue , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/metabolismo , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/metabolismo , Prognóstico , Metais/sangue , Metais/metabolismo , Metais/análise , Pâncreas/metabolismo , Pâncreas/patologia , Magnésio/sangue , Magnésio/metabolismo , Magnésio/análise , Adulto , Cálcio/sangue , Cálcio/metabolismo , Cálcio/análise , Selênio/sangue , Selênio/análise , Selênio/metabolismo , Ferro/metabolismo , Ferro/sangue , Zinco/sangue , Zinco/metabolismo , Zinco/análise , Molibdênio/sangue
17.
J Dent ; 145: 104966, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38554802

RESUMO

INTRODUCTION: The decline in dental caries has been attributed to the widespread use of fluoride (F). Two forms of presentation are fluoridated toothpaste (FT) and mouthwash (MW), widely used by the population. MATERIALS AND METHODS: This study aimed to evaluate in vitro the effects of combining FT and MW, whether supplemented with sodium trimetaphosphate (TMP) or not, on dental enamel demineralization. Bovine enamel blocks (n = 60) were selected based on initial surface hardness (SHi) and divided into 5 experimental groups (n = 12 each): I) Placebo Toothpaste (without F/TMP); II) 1100 ppm F Toothpaste (FT); III) 1100F associated with a MW at 100 ppm F (FT + MW 100F); IV) 1100F associated with a MW at 225 ppm F (FT + MW 250F); and V) 1100F associated with a MW at 100 ppm F supplemented with 0.4 % TMP (FT + MW 100F-TMP). The blocks were treated twice a day, undergoing 5 pH cycles over 7 days. Thus, the percentage change in surface hardness (%SH), integrated subsurface hardness loss (ΔKHN), and the concentration of F, phosphorus (P), and calcium (Ca) in the enamel were determined. The data were submitted to ANOVA and Student-Newman-Keuls test (p < 0.001). RESULTS: The 1100F group was statistically inferior to the groups associated with MW for %SH, ΔKHN, and the concentration of P and Ca in the enamel (p < 0.001). Blocks treated with FT + MW 225F and FT + MW 100F-TMP showed significantly lower %SH compared to the other groups (p < 0.001). The FT + MW 100F - TMP group exhibited the lowest depth mineral loss (ΔKHN), and higher concentration de P in enamel (p < 0.001). CONCLUSION: The adjunct use of MW with FT produces a greater protective effect in inhibiting enamel demineralization, and the supplementation of TMP to the MW with 100F provides a superior effect compared to MW with 225F. CLINICAL SIGNIFICANCE: This combination of treatments could be regarded as one of several alternative fluoride supplements for subjects at elevated risk of caries.


Assuntos
Cariostáticos , Esmalte Dentário , Fluoretos , Dureza , Antissépticos Bucais , Polifosfatos , Desmineralização do Dente , Cremes Dentais , Animais , Bovinos , Polifosfatos/uso terapêutico , Polifosfatos/farmacologia , Desmineralização do Dente/prevenção & controle , Esmalte Dentário/efeitos dos fármacos , Cariostáticos/uso terapêutico , Cremes Dentais/uso terapêutico , Cremes Dentais/química , Antissépticos Bucais/uso terapêutico , Fluoretos/uso terapêutico , Concentração de Íons de Hidrogênio , Cálcio/uso terapêutico , Cálcio/análise , Teste de Materiais
18.
Environ Monit Assess ; 196(4): 398, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530475

RESUMO

The current study was conducted within the context of the Holocene era in Sebkha El-Guettiate, located in southeastern Tunisia. The aim was to determine the factors influencing the geochemical and mineralogical composition of sediments and to elucidate the sedimentary characteristics of the Holocene within the Sebkha core. We examined a sediment core extending 100 cm from this Sebkha, subjecting it to comprehensive analysis to uncover its sedimentological, mineralogical, and geochemical properties. Several techniques were employed to strengthen and validate the connections between geochemical and mineralogical analyses, including X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), and infrared (IR) spectroscopy, among others. Furthermore, statistical analyses utilizing principal component analysis (PCA) were applied to the results of the geochemical and mineralogical studies, aiding in the identification of patterns and relationships. A comprehensive mineralogical assessment of the core's sediments revealed the presence and interpretation of carbonate minerals, evaporite minerals, and detrital minerals. Through the application of infrared (IR) spectrometer techniques to all sediment samples, we gained insight into the mineralogical components and the distribution of key elements such as quartz, kaolinite, calcite, feldspar, and organic carbon. The geochemical composition demonstrated a clear dominance of silica (SiO2), accompanied by fluctuations in carbonate percentages (CaCO3). The prominent major elements, primarily magnesium (Mg) and calcium (Ca) originating from dolomitization, sodium (Na) and chlorine (Cl) from halite, and calcium (Ca) from gypsum, exhibited varying levels. Results from Rock-Eval 6 pyrolysis indicated that the organic matter within the sediments is generally a mixture of terrestrial and aquatic origins. This study provides practical information that underscores the diverse origins contributing to Sebkha sediment formation, often influenced by saline systems.


Assuntos
Cálcio , Dióxido de Silício , Cálcio/análise , Dióxido de Silício/análise , Tunísia , Monitoramento Ambiental , Minerais/análise , Carbonato de Cálcio/análise , Carbonatos/análise
19.
Nature ; 627(8005): 821-829, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38448584

RESUMO

Animals in the natural world constantly encounter geometrically complex landscapes. Successful navigation requires that they understand geometric features of these landscapes, including boundaries, landmarks, corners and curved areas, all of which collectively define the geometry of the environment1-12. Crucial to the reconstruction of the geometric layout of natural environments are concave and convex features, such as corners and protrusions. However, the neural substrates that could underlie the perception of concavity and convexity in the environment remain elusive. Here we show that the dorsal subiculum contains neurons that encode corners across environmental geometries in an allocentric reference frame. Using longitudinal calcium imaging in freely behaving mice, we find that corner cells tune their activity to reflect the geometric properties of corners, including corner angles, wall height and the degree of wall intersection. A separate population of subicular neurons encode convex corners of both larger environments and discrete objects. Both corner cells are non-overlapping with the population of subicular neurons that encode environmental boundaries. Furthermore, corner cells that encode concave or convex corners generalize their activity such that they respond, respectively, to concave or convex curvatures within an environment. Together, our findings suggest that the subiculum contains the geometric information needed to reconstruct the shape and layout of naturalistic spatial environments.


Assuntos
Meio Ambiente , Percepção de Forma , Hipocampo , Neurônios , Animais , Feminino , Masculino , Camundongos , Cálcio/análise , Cálcio/metabolismo , Percepção de Forma/fisiologia , Hipocampo/citologia , Hipocampo/fisiologia , Neurônios/metabolismo , Neurônios/fisiologia , Propriedades de Superfície
20.
Food Chem ; 447: 138952, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38461720

RESUMO

The edible coating is proved to be a convenient approach for fruit preservation. Among these published explorations, naturally sourced macromolecules and green crosslinking strategies gain attention. This work centers on edible coatings containing Ca2+ as crosslinker for the first time, delving into crosslinking mechanisms, include alginate, chitosan, Aloe vera gel, gums, etc. Additionally, the crucial functions of Ca2+ in fruit's quality control are also elaborated in-depth, involving cell wall, calmodulin, antioxidant, etc. Through a comprehensive review, it becomes evident that Ca2+ plays a dual role in fruit edible coating. Specifically, Ca2+ constructs a three-dimensional dense network structure with polymers through ionic bonding. Moreover, Ca2+ acts directly with cell wall to maintain fruit firmness and serve as a second messenger to participate secondary physiological metabolism. In brief, coatings containing Ca2+ present remarkable effects in preserving fruit and this work may provide guidance for Ca2+ related fruit preservation coatings.


Assuntos
Filmes Comestíveis , Conservação de Alimentos , Conservação de Alimentos/métodos , Cálcio/análise , Polímeros/análise , Frutas/química
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