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1.
Artigo em Inglês | MEDLINE | ID: mdl-38561623

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM), the most prevalent form of central nervous system (CNS) cancer, stands as a highly aggressive glioma deemed virtually incurable according to the World Health Organization (WHO) standards, with survival rates typically falling between 6 to 18 months. Despite concerted efforts, advancements in survival rates have been elusive. Recent cutting-edge research has unveiled bionanocatalysts with 1% Pt, demonstrating unparalleled selectivity in cleaving C-C, C-N, and C-O bonds within DNA in malignant cells. The application of these nanoparticles has yielded promising outcomes. OBJECTIVE: The objective of this study is to employ bionanocatalysts for the treatment of Glioblastoma Multiforme (GBM) in a patient, followed by the evaluation of obtained tissues through electronic microscopy. METHODS: Bionanocatalysts were synthesized using established protocols. These catalysts were then surgically implanted into the GBM tissue through stereotaxic procedures. Subsequently, tissue samples were extracted from the patient and meticulously examined using Scanning Electron Microscopy (SEM). RESULTS AND DISCUSSION: Detailed examination of biopsies via SEM unveiled a complex network of small capillaries branching from a central vessel, accompanied by a significant presence of solid carbonate formations. Remarkably, the patient subjected to this innovative approach exhibited a three-year extension in survival, highlighting the potential efficacy of bionanocatalysts in combating GBM and its metastases. CONCLUSION: Bionanocatalysts demonstrate promise as a viable treatment option for severe cases of GBM. Additionally, the identification of solid calcium carbonate formations may serve as a diagnostic marker not only for GBM but also for other CNS pathologies.

2.
Heliyon ; 10(2): e24442, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38293433

RESUMO

Food fortification has attracted interest in recent years, due to the understanding that micronutrient deficiency is one of the causes of the global burden of disease, and that food fortification aims to prevent or correct a demonstrated deficiency of one or more nutrients in a specific population or population groups. Nutritional value is an important concern regarding fortification and new product development. However, people are not willing to sacrifice the organoleptic characteristics of food products. Therefore, the effect of CaCO3 nanoparticles (NPs-CaCO3) and commercial CaCO3 on the physical and sensory properties of three food matrices (cookies, fruit rolls and dairy desserts) was evaluated. A texture analysis was performed on cookies and fruit rolls; a viscosity analysis on dairy desserts; and a color analysis and sensory profile on the three matrices. The results showed that both types of calcium increase hardness in fortified biscuits and fruit rolls but, in the latter case, commercial calcium caused a higher increase in hardness (p < 0.05). Viscosity was higher in the desserts with NPs. Color presented significant changes in all the fortified matrices. These findings demonstrated that Ca-NPs are a good strategy for food fortification compared to commercial calcium carbonate, as fortification with high levels of calcium is a challenge for the food industry due to its effects on the product. The results showed that, in the matrices with commercial calcium, the changes were more evident, while the matrices fortified with Ca-NP have a better sensory response than commercial Ca, with a higher level of acceptance by the judges. Therefore Ca-NPs can be considered to be a good source of calcium for food product fortification that causes a slight effect on physical and sensory properties.

3.
Mar Environ Res ; 172: 105490, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34628146

RESUMO

Emerging evidence have been supporting the idea that the better known South Atlantic coral reefs (located between 18°S and 24°S) are now essentially senescent structures that have experienced little or no additional vertical reef growth over the past millennia. This has often coincided with a shift to a dominance of non-coral calcifying organisms becoming the main CaCO3 producers in these high latitude and marginal marine settings. Here, we used Calcification Accretion Units (CAUs) and census-based methods to measure non-coral rates of CaCO3 production on the geologically senescent reef and adjacent rhodolith beds within the southernmost subtropical Atlantic reef (i.e., Queimada Grande Reef, QGR). The reef habitat is currently producing CaCO3 at rates of ∼126 g m-2 yr-1. In contrast, fragments of dead corals skeletons deposited adjacent to the reef over the last ∼2000 years are now colonized by crustose coralline red algae. These form a rhodolith bed that produces CaCO3 at rates of 858 g m-2 yr-1. Our results indicate that, whilst not sufficient to promote active net framework accumulation, CaCO3 production by coralline algae and bryozoans on the QGR appears to be sufficient to at least limit net large-scale erosion of the underlying reef structure, allowing the reef structure to persist in a state close to budgetary stasis. Finally, our results are also of relevance for providing insights regarding the balance of CaCO3 production/dissolution/erosion processes in coral reefs, especially in these less understood marginal reefs.


Assuntos
Antozoários , Briozoários , Animais , Carbonato de Cálcio , Recifes de Corais , Ecossistema
4.
Materials (Basel) ; 14(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064575

RESUMO

Whey in large quantities can cause environmental problems when discarded, because it reduces dissolved oxygen and aquatic life. Nonetheless, it could be used as an easily available and economical alternative to reduce culture medium costs in microbially induced calcium carbonate precipitation (MICP). In this work, a native Sporosarcina pasteurii was isolated and then cultured by using different proportions of whey (W) in nutrient broth (NB). The solids were characterized by XRD, FT-IR, TGA, and SEM. The potential applications in bioconsolidation were also studied. Whey concentration was directly related to CaCO3 production. Higher whey concentrations reduced calcium carbonate purity to nearly 80%. All experiments showed calcite and vaterite fractions, where a whey increment in the media increased calcite content and decreased vaterite content, causing a decrease in crystal size. MICP improved compressive strength (CS) in sand and fly ash. The best CS results were obtained by fly ash treated with 25 W-75 NB (37.2 kPa) and sand with 75 W-25 NB (32.1 kPa). Whey changed crystal polymorphism in biogenic CaCO3 production. Material bioconsolidation depends on the CaCO3 polymorph, thus fly ash was effectively bioconsolidated by crystallization of vaterite and sand by crystallization of calcite.

5.
Molecules ; 24(1)2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30602678

RESUMO

CaCO3 nanoparticles of around 60 nm were obtained by a co-precipitation method and used as filler to prepare low-density polyethylene (LDPE) composites by melt blending. The nanoparticles were also organically modified with oleic acid (O-CaCO3) in order to improve their interaction with the LDPE matrix. By adding 3 and 5 wt% of nanofillers, the mechanical properties under tensile conditions of the polymer matrix improved around 29%. The pure LDPE sample and the nanocomposites with 5 wt% CaCO3 were photoaged by ultraviolet (UV) irradiation during 35 days and the carbonyl index (CI), degree of crystallinity (χc), and Young's modulus were measured at different times. After photoaging, the LDPE/CaCO3 nanocomposites increased the percent crystallinity (χc), the CI, and Young's modulus as compared to the pure polymer. Moreover, the viscosity of the photoaged nanocomposite was lower than that of photoaged pure LDPE, while scanning electron microscopy (SEM) analysis showed that after photoaging the nanocomposites presented cavities around the nanoparticles. These difference showed that the presence of CaCO3 nanoparticles accelerate the photo-degradation of the polymer matrix. Our results show that the addition of CaCO3 nanoparticles into an LDPE polymer matrix allows future developments of more sustainable polyethylene materials that could be applied as films in agriculture. These LDPE-CaCO3 nanocomposites open the opportunity to improve the low degradation of the LDPE without sacrificing the polymer's behavior, allowing future development of novel eco-friendly polymers.


Assuntos
Carbonato de Cálcio/química , Ácido Oleico/química , Polietileno/química , Módulo de Elasticidade , Nanocompostos/química , Nanopartículas/química , Fotólise
6.
Braz. j. biol ; Braz. j. biol;77(2): 304-311, Apr.-June 2017. graf
Artigo em Inglês | LILACS | ID: biblio-888735

RESUMO

Abstract Calcium is considered an essential element for the metabolism of aquatic snail Biomphalaria glabrata (Say, 1818), intermediate host of Schistosoma mansoni Sambon, 1907 in Brazil, and represents a limiting factor to its distribution and adaptation to the environment. This study investigated the effect of different concentrations of exogenous CaCO3 on the energetic metabolism of B. glabrata for better understanding the physiological interference of chemical elements dissolved in the environment with the physiology of this species. Sixty-day-old snails were distributed into six groups, five exposed to different concentrations of CaCO3 (20, 40, 60, 80 and 100 mg/L) and a control group. The exposure to CaCO3 was assessed over time, with analysis of 15 snails of each group in the following intervals: 1, 14, 21 or 30 days for hemolymph extraction. Concentrations of calcium and glucose in the hemolymph were determined by commercial kits, and organic acids were extracted using an ion exchange column and analyzed by high-performance liquid chromatography. Concentration of calcium in the hemolymph showed no significant difference (p>0.05) from the control group and between the concentrations tested. Concentration of glucose decreased (p<0.05) in the treatments of exposure to 20 and 40 mg/L and increased when exposed to 80 and 100 mg/L CaCO3 compared to control and to other concentrations tested over 30 days. The organic acids pyruvate, oxaloacetate, citrate, succinate, fumarate, beta-hydroxybutyrate and lactate presented increased concentrations, while propionate and acetoacetate, decreased concentrations, when exposed to CaCO3 compared to control. Considering the influence of different periods of exposure to CaCO3, on the 14th day, there were stronger alterations in the metabolism of B. glabrata. In conclusion, exposure to CaCO3 reduced the concentration of glucose, which is metabolized into pyruvate, the final product of glycolysis, and also influenced the energetic metabolism pathways, indicating an aerobic or partially anaerobic functioning.


Resumo O cálcio é considerado um elemento essencial no metabolismo do molusco aquático Biomphalaria glabrata (Say, 1818), principal hospedeiro intermediário de Schistosoma mansoni Sambon, 1907 no Brasil e, tem sido descrito como um fator limitante na distribuição e adaptação desse molusco no ambiente. O presente trabalho avaliou o efeito de diferentes concentrações de carbonato de cálcio (CaCO3) exógeno ao metabolismo energético de B. glabrata, a fim de subsidiar uma melhor compreensão da interferência de elementos químicos dissolvidos no meio aquático na fisiologia destes moluscos. Foram utilizados moluscos com sessenta dias de vida, distribuídos em seis grupos, cinco expostos a diferentes concentrações de CaCO3 (20, 40, 60, 80 e 100mg/L) e um controle. A exposição ao CaCO3 foi avaliada em função do tempo, sendo retirados 15 moluscos de cada grupo nos seguintes intervalos: 1, 14, 21 ou 30 dias para extração da hemolinfa. As concentrações de cálcio e glicose na hemolinfa foram determinadas usando-se kits comercial e os ácidos orgânicos foram extraídos por meio da coluna de troca iônica e analisados através cromatografia líquida de alta eficiência. Os resultados demonstraram que a concentração de cálcio na hemolinfa não apresentou diferença significativa (p>0,05) em relação ao controle e nas concentrações testadas. A concentração de glicose diminuiu (p<0,05) nas exposições a 20 mg e 40 mg/L e aumentou nas exposições a 80 mg e 100 mg/L de CaCO3 em relação ao controle e demais concentrações testadas ao longo de 30 dias. Os ácidos orgânicos piruvato, oxaloaceato, citrato, succinato, fumarato, β-hidroxibutirato e lactato tiveram suas concentrações aumentadas, enqunato, propionato e acetoacetato tiveram suas concentrações diminuídas na exposição ao CaCO3 comparada ao controle. Quanto a influência dos diferentes períodos de exposição ao CaCO3, aos 14 dias, as alterações no metabolismo de B. glabrata foram mais expressivas. Conclui-se que as exposições ao CaCO3 influenciaram na redução de glicose, sendo esta metabolizada a piruvato, produto final da glicólise e alteraram as vias de metabolismo energético, indicando um funcionamento aeróbio ou parcialmente anaeróbio.


Assuntos
Animais , Biomphalaria/metabolismo , Carbonato de Cálcio/metabolismo , Cálcio da Dieta/metabolismo , Metabolismo Energético , Biomphalaria/efeitos dos fármacos , Carbonato de Cálcio/administração & dosagem , Cálcio da Dieta/administração & dosagem , Distribuição Aleatória , Relação Dose-Resposta a Droga
7.
Braz. J. Biol. ; 77(2): 304-311, abr.-jun. 2017. ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-734974

RESUMO

Calcium is considered an essential element for the metabolism of aquatic snail Biomphalaria glabrata (Say, 1818), intermediate host of Schistosoma mansoni Sambon, 1907 in Brazil, and represents a limiting factor to its distribution and adaptation to the environment. This study investigated the effect of different concentrations of exogenous CaCO3 on the energetic metabolism of B. glabrata for better understanding the physiological interference of chemical elements dissolved in the environment with the physiology of this species. Sixty-day-old snails were distributed into six groups, five exposed to different concentrations of CaCO3 (20, 40, 60, 80 and 100 mg/L) and a control group. The exposure to CaCO3 was assessed over time, with analysis of 15 snails of each group in the following intervals: 1, 14, 21 or 30 days for hemolymph extraction. Concentrations of calcium and glucose in the hemolymph were determined by commercial kits, and organic acids were extracted using an ion exchange column and analyzed by high-performance liquid chromatography. Concentration of calcium in the hemolymph showed no significant difference (p>0.05) from the control group and between the concentrations tested...(AU)


O cálcio é considerado um elemento essencial no metabolismo do molusco aquático Biomphalaria glabrata (Say, 1818), principal hospedeiro intermediário de Schistosoma mansoni Sambon, 1907 no Brasil e, tem sido descrito como um fator limitante na distribuição e adaptação desse molusco no ambiente. O presente trabalho avaliou o efeito de diferentes concentrações de carbonato de cálcio (CaCO3) exógeno ao metabolismo energético de B. glabrata, a fim de subsidiar uma melhor compreensão da interferência de elementos químicos dissolvidos no meio aquático na fisiologia destes moluscos. Foram utilizados moluscos com sessenta dias de vida, distribuídos em seis grupos, cinco expostos a diferentes concentrações de CaCO3 (20, 40, 60, 80 e 100mg/L) e um controle. A exposição ao CaCO3 foi avaliada em função do tempo, sendo retirados 15 moluscos de cada grupo nos seguintes intervalos: 1, 14, 21 ou 30 dias para extração da hemolinfa. As concentrações de cálcio e glicose na hemolinfa foram determinadas usando-se kits comercial e os ácidos orgânicos foram extraídos por meio da coluna de troca iônica e analisados através cromatografia líquida de alta eficiência. Os resultados demonstraram que a concentração de cálcio na hemolinfa não apresentou diferença significativa (p>0,05) em relação ao controle e nas concentrações testadas...(AU)


Assuntos
Animais , Biomphalaria/metabolismo , Metabolismo Energético , Cálcio/administração & dosagem , Homeostase
8.
Biofouling ; 30(5): 547-60, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24689777

RESUMO

Heterotrophic CaCO3-precipitating bacteria were isolated from biofilms on deteriorated ignimbrites, siliceous acidic rocks, from Morelia Cathedral (Mexico) and identified as Enterobacter cancerogenus (22e), Bacillus sp. (32a) and Bacillus subtilis (52g). In solid medium, 22e and 32a precipitated calcite and vaterite while 52g produced calcite. Urease activity was detected in these isolates and CaCO3 precipitation increased in the presence of urea in the liquid medium. In the presence of calcium, EPS production decreased in 22e and 32a and increased in 52g. Under laboratory conditions, ignimbrite colonization by these isolates only occurred in the presence of calcium and no CaCO3 was precipitated. Calcium may therefore be important for biofilm formation on stones. The importance of the type of stone, here a siliceous stone, on biological colonization is emphasized. This calcium effect has not been reported on calcareous materials. The importance of the effect of calcium on EPS production and biofilm formation is discussed in relation to other applications of CaCO3 precipitation by bacteria.


Assuntos
Bacillus/fisiologia , Biofilmes , Carbonato de Cálcio/metabolismo , Enterobacter/fisiologia , Bacillus/genética , Bacillus/isolamento & purificação , Carbonato de Cálcio/química , Precipitação Química , Enterobacter/genética , Enterobacter/isolamento & purificação , Processos Heterotróficos , México , Dados de Sequência Molecular , Filogenia , Propriedades de Superfície
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