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1.
J Vis Exp ; (170)2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33999031

RESUMO

Nonlocalized mechanical forces, such as vibrations and acoustic waves, influence a wide variety of biological processes from development to homeostasis. Animals cope with these stimuli by modifying their behavior. Understanding the mechanisms underlying such behavioral modification requires quantification of neural activity during the behavior of interest. Here, we report a method for calcium imaging in freely behaving Caenorhabditis elegans with nonlocalized vibration of specific frequency, displacement, and duration. This method allows the production of well-controlled, nonlocalized vibration using an acoustic transducer and quantification of evoked calcium responses at single-cell resolution. As a proof of principle, the calcium response of a single interneuron, AVA, during the escape response of C. elegans to vibration is demonstrated. This system will facilitate understanding of neural mechanisms underlying behavioral responses to mechanical stimuli.


Assuntos
Cálcio/análise , Animais , Comportamento Animal , Caenorhabditis elegans/química , Caenorhabditis elegans/metabolismo , Cálcio/metabolismo , Interneurônios/fisiologia , Vibração
2.
Nat Commun ; 12(1): 2556, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33963184

RESUMO

Ensuring that global warming remains <2 °C requires rapid CO2 emissions reduction. Additionally, 100-900 gigatons CO2 must be removed from the atmosphere by 2100 using a portfolio of CO2 removal (CDR) methods. Ocean afforestation, CDR through basin-scale seaweed farming in the open ocean, is seen as a key component of the marine portfolio. Here, we analyse the CDR potential of recent re-occurring trans-basin belts of the floating seaweed Sargassum in the (sub)tropical North Atlantic as a natural analogue for ocean afforestation. We show that two biogeochemical feedbacks, nutrient reallocation and calcification by encrusting marine life, reduce the CDR efficacy of Sargassum by 20-100%. Atmospheric CO2 influx into the surface seawater, after CO2-fixation by Sargassum, takes 2.5-18 times longer than the CO2-deficient seawater remains in contact with the atmosphere, potentially hindering CDR verification. Furthermore, we estimate that increased ocean albedo, due to floating Sargassum, could influence climate radiative forcing more than Sargassum-CDR. Our analysis shows that multifaceted Earth-system feedbacks determine the efficacy of ocean afforestation.


Assuntos
Atmosfera/análise , Dióxido de Carbono/análise , Aquecimento Global/prevenção & controle , Sargassum/isolamento & purificação , Oceano Atlântico , Biomassa , Cálcio/análise , Ecossistema , Retroalimentação , Concentração de Íons de Hidrogênio , Água do Mar/análise , Água do Mar/química , Temperatura , Fatores de Tempo , Clima Tropical
3.
BMJ ; 373: n776, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947652

RESUMO

First developed in 1990, the Agatston coronary artery calcium (CAC) score is an international guideline-endorsed decision aid for further risk assessment and personalized management in the primary prevention of atherosclerotic cardiovascular disease. This review discusses key international studies that have informed this 30 year journey, from an initial coronary plaque screening paradigm to its current role informing personalized shared decision making. Special attention is paid to the prognostic value of a CAC score of zero (the so called "power of zero"), which, in a context of low estimated risk thresholds for the consideration of preventive therapy with statins in current guidelines, may be used to de-risk individuals and thereby inform the safe delay or avoidance of certain preventive therapies. We also evaluate current recommendations for CAC scoring in clinical practice guidelines around the world, and past and prevailing barriers for its use in routine patient care. Finally, we discuss emerging approaches in this field, with a focus on the potential role of CAC informing not only the personalized allocation of statins and aspirin in the general population, but also of other risk-reduction therapies in special populations, such as individuals with diabetes and people with severe hypercholesterolemia.


Assuntos
Aterosclerose/prevenção & controle , Cálcio/análise , Vasos Coronários/química , Guias de Prática Clínica como Assunto , Prevenção Primária/normas , Aterosclerose/diagnóstico , Aterosclerose/epidemiologia , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Diabetes Mellitus/epidemiologia , Humanos , Hipercolesterolemia/epidemiologia , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , Literatura de Revisão como Assunto , Medição de Risco/métodos , Fatores de Risco
4.
Int J Nanomedicine ; 16: 3041-3057, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33948084

RESUMO

Background: The dentin exposure always leads to dentin hypersensitivity and/or caries. Given the dentin's tubular structure and low mineralization degree, reestablishing an effective biobarrier to stably protect dentin remains significantly challenging. This study reports a versatile dentin surface biobarrier consisting of a mesoporous silica-based epigallocatechin-3-gallate (EGCG)/nanohydroxyapatite delivery system and evaluates its stability on the dentinal tubule occlusion and the Streptococcus mutans (S. mutans) biofilm inhibition. Materials and Methods: The mesoporous delivery system was fabricated and characterized. Sensitive dentin discs were prepared and randomly allocated to three groups: 1, control group; 2, casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) group; and 3, the mesoporous delivery system group. The dentin permeability, dentinal tubule occlusion, acid and abrasion resistance, and S. mutans biofilm inhibition were determined for 1 week and 1 month. The in vitro release profiles of EGCG, Ca, and P were also monitored. Results: The mesoporous delivery system held the ability to sustainably release EGCG, Ca, and P and could persistently occlude dentinal tubules with acid and abrasion resistance, reduce the dentin permeability, and inhibit the S. mutans biofilm formation for up to 1 month compared with the two other groups. The system provided prolonged stability to combat oral adverse challenges and served as an effective surface biobarrier to protect the exposed dentin. Conclusion: The establishment of the dentin surface biobarrier consisting of a mesoporous delivery system indicates a promising strategy for the prevention and the management of dentin hypersensitivity and caries after enamel loss.


Assuntos
Biofilmes/crescimento & desenvolvimento , Dentina/química , Streptococcus mutans/fisiologia , Ácidos , Adsorção , Biofilmes/efeitos dos fármacos , Cálcio/análise , Caseínas/farmacologia , Catequina/análogos & derivados , Catequina/química , Catequina/farmacologia , Morte Celular/efeitos dos fármacos , Contagem de Colônia Microbiana , Polpa Dentária/citologia , Humanos , Nanopartículas/química , Nanopartículas/ultraestrutura , Nitrogênio/química , Permeabilidade , Fósforo/análise , Porosidade , Dióxido de Silício/química , Streptococcus mutans/ultraestrutura
5.
Food Chem ; 359: 129865, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33940467

RESUMO

To study the effects of dairy production system on milk macromineral and trace element concentrations, milk samples were collected monthly in 2019 from 43 conventional and 27 organic farms. Organic milk contained more Ca (1049.5 vs. 995.8 mg/kg), K (1383.6 vs. 1362.4 mg/kg), P (806.5 vs. 792.5 mg/kg) and Mo (73.3 vs. 60.6 µg/kg) but less Cu (52.4 vs. 60.6 µg/kg), Fe (0.66 vs 2.03 mg/kg), Mn (28.8 vs. 45.0 µg/kg), Zn (4.51 vs. 5.00 mg/kg) and Al (0.32 vs. 1.14 µg/kg) than conventional milk. Significant seasonal variation was observed in all determined minerals' concentrations. Milk I concentration was not consistently affected by production system, whereas organic milk contained less I in June and July than conventional milk. Dietary factors contributing to different milk mineral concentrations between production systems included intakes of maize silage, dry-straights and oils (higher in conventional diets), and pasture, clover and wholecrop (higher in organic diets).


Assuntos
Leite/química , Agricultura Orgânica , Oligoelementos/análise , Animais , Cálcio/análise , Dieta/veterinária , Feminino , Ferro/análise , Potássio/análise , Estações do Ano , Silagem , Trifolium , Zea mays
6.
Diabetes Res Clin Pract ; 176: 108867, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34023340

RESUMO

AIMS: Maturity-Onset Diabetes of the Young (MODY) caused by glucokinase (GCK) mutations is characterized by lifelong mild non-progressive hyperglycemia, with low frequency of coronary artery disease (CAD) compared to other types of diabetes. The aim of this study is to estimate cardiovascular risk by coronary artery calcification (CAC) score in this group. MATERIALS AND METHODS: Twenty-nine GCK-MODY cases, 26 normoglycemic controls (recruited among non-affected relatives/spouses of GCK mutation carriers), and 24 unrelated individuals with type 2 diabetes were studied. Patients underwent CAC score evaluation by computed tomography and were classified by Agatston score ≥ or < 10. Framingham Risk scores of CAD in 10 years were calculated. RESULTS: Median [interquartile range] CAC score in GCK-MODY was 0 [0,0], similar to controls (0 [0,0], P = 0.49), but lower than type 2 diabetes (39 [0, 126], P = 2.6 × 10-5). A CAC score ≥ 10 was seen in 6.9% of the GCK group, 7.7% of Controls (P = 1.0), and 54.2% of individuals with type 2 diabetes (P = 0.0006). Median Framingham risk score was lower in GCK than type 2 diabetes (3% vs. 13%, P = 4 × 10-6), but similar to controls (3% vs. 4%, P = 0.66). CONCLUSIONS: CAC score in GCK-MODY is similar to control individuals from the same family and/or household and is significantly lower than type 2 diabetes. Besides demonstrating low risk of CAD in GCK-MODY, these findings may contribute to understanding the specific effect of hyperglycemia in CAD.


Assuntos
Cálcio/sangue , Vasos Coronários/metabolismo , Diabetes Mellitus Tipo 2/diagnóstico , Fatores de Risco de Doenças Cardíacas , Adulto , Idoso , Cálcio/análise , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Estudos de Casos e Controles , Vasos Coronários/química , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/diagnóstico , Feminino , Glucoquinase/genética , Humanos , Hiperglicemia/genética , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Medição de Risco , Fatores de Risco
7.
Nutrients ; 13(5)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922719

RESUMO

This study aimed to estimate the distribution of usual intakes in protein, sodium, potassium, and calcium by age group and assessed whether proportions of deficiencies/excesses of each nutrient would occur more in older age via a comparison with the dietary reference intakes for the Japanese population (DRIs_J). A cross-sectional analysis was conducted using a database of the 2-day nutrient intake of 361 Japanese people aged 65-90 years. The AGEVAR MODE was used to estimate usual intake. Percentile curves using estimated distribution by sex and age and usual nutrient intake were compared to those of the DRIs_J. The usual intake of protein (male and female) and potassium and calcium (female) were lower with older age. Within-individual variance of protein in female (p = 0.037) and calcium in male (p = 0.008) subjects were considerably lower with older age. The proportion of deficiencies in protein (male and female), potassium (female), and calcium (female) were higher with older age. However, the proportion of people with excess salt (converted from sodium; male and female) did not differ by age. The variances found herein could be important for enhancing the understanding of differences in dietary intake by age.


Assuntos
Grupo com Ancestrais do Continente Asiático , Nutrientes , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Cálcio/análise , Dieta , Feminino , Humanos , Japão , Estilo de Vida , Masculino , Potássio/análise , Valores de Referência
8.
Molecules ; 26(8)2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33924574

RESUMO

Date palm fruit (Phoenix dactylifera L.) is commonly consumed around the world and has recently become an economical crop in Eastern Thailand, especially the Barhi cultivar that can be consumed as fresh fruit. To maintain genetic qualities, date palm is populated through cell culture. This leads to high production costs, while access to this technique is limited. Increasing date palm population by simple seed planting is currently of interest as an alternative for local farmers. Nevertheless, information on nutritive values, bioactive compounds, and health-promoting bioactivities of seed originating from date palm fruit is unavailable. Effects of different planting origins (cell culture origin (CO) and seed origin (SO)) of date palm fruits at the Khalal stage of Barhi cultivar were investigated for nutritive values, bioactive compounds, and in vitro health-promoting properties via key enzyme inhibitions against obesity (lipase), diabetes (α-amylase, α-glucosidase, and dipeptidyl peptidase-IV), Alzheimer's disease (cholinesterases and ß-secretase), and hypertension (angiotensin-converting enzyme). Waste seeds as a by-product from date palm production were also examined regarding these properties to increase seed marketing opportunities for future food applications and other health-related products. CO and SO exhibited insignificant differences in energy, fat, and carbohydrate contents. SO had higher protein, dietary fiber, vitamin A, vitamin E, and calcium contents than CO, while CO contained higher contents of fructose, glucose and maltose. Higher phenolic contents in SO led to greater enzyme inhibitory activities than CO. Interestingly, seeds of date palm fruits mostly contained higher nutritive values than the flesh. No carotenoids were detected in seeds but higher phenolic contents resulted in greater enzyme inhibitory activities than recorded for fruit flesh. Results suggest that appropriate planting of date palm can support the development of novel date palm fruit products, leading to expansion of economic opportunities and investment in date palm fruit agriculture.


Assuntos
Agricultura/métodos , Frutas/química , Phoeniceae/química , Sementes/química , Cálcio/análise , Carotenoides/análise , Fibras na Dieta/análise , Valor Nutritivo , Vitamina A/análise , Vitamina E/análise
9.
Molecules ; 26(7)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917454

RESUMO

The biodegradable metals, including magnesium (Mg), are a convenient alternative to permanent metals but fast uncontrolled corrosion limited wide clinical application. Formation of a barrier coating on Mg alloys could be a successful strategy for the production of a stable external layer that prevents fast corrosion. Our research was aimed to develop an Mg stable oxide coating using plasma electrolytic oxidation (PEO) in silicate-based solutions. 99.9% pure Mg alloy was anodized in electrolytes contained mixtures of sodium silicate and sodium fluoride, calcium hydroxide and sodium hydroxide. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), contact angle (CA), Photoluminescence analysis and immersion tests were performed to assess structural and long-term corrosion properties of the new coating. Biocompatibility and antibacterial potential of the new coating were evaluated using U2OS cell culture and the gram-positive Staphylococcus aureus (S. aureus, strain B 918). PEO provided the formation of a porous oxide layer with relatively high roughness. It was shown that Ca(OH)2 was a crucial compound for oxidation and surface modification of Mg implants, treated with the PEO method. The addition of Ca2+ ions resulted in more intense oxidation of the Mg surface and growth of the oxide layer with a higher active surface area. Cell culture experiments demonstrated appropriate cell adhesion to all investigated coatings with a significantly better proliferation rate for the samples treated in Ca(OH)2-containing electrolyte. In contrast, NaOH-based electrolyte provided more relevant antibacterial effects but did not support cell proliferation. In conclusion, it should be noted that PEO of Mg alloy in silicate baths containing Ca(OH)2 provided the formation of stable biocompatible oxide coatings that could be used in the development of commercial degradable implants.


Assuntos
Eletrólise , Magnésio/farmacologia , Gases em Plasma/química , Silicatos/química , Antibacterianos/farmacologia , Líquidos Corporais/química , Cálcio/análise , Linhagem Celular Tumoral , Sobrevivência Celular , Materiais Revestidos Biocompatíveis/farmacologia , Eletrodos , Humanos , Luminescência , Testes de Sensibilidade Microbiana , Oxirredução , Fósforo/análise , Soluções , Espectrometria por Raios X , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
10.
Food Funct ; 12(6): 2660-2671, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33650606

RESUMO

The high intake of sodium and low intake of dietary fiber are two major dietary risk factors for preventable deaths worldwide, highlighting the need and implementations for developing health foods with low-salt/high-dietary fibers. Bread as a staple food contributes about 25% to the daily intake of sodium in many countries, and salt reduction in bread still remains a great technical challenge. In this study, we developed a simple method to reformulate the white bread in terms of reducing salt contents via dietary fiber fortification, while maintaining the taste and texture qualities. Low molecular weight water-extractable arabinoxylans (LMW-WEAX) as a soluble dietary fiber was first hydrated in salt water before dough mixing, leading to an inhomogeneous spatial distribution of sodium in bread and accelerating the release of sodium ions from crumbs, allowing 20% salt reduction in bread without impacting the salt perception. Data from the moisture content, crumb structure, water distribution, dough rheology and bread texture properties suggest that the pre-hydrated incorporation of LMW-WEAX mitigates the detrimental effect of dietary fiber on the dough and bread quality. The modulation of Ca2+ on the permeability of Na+ through the mucus layer and implication in salt enhancement of the bread were investigated. Results show that the pre-hydrated incorporation of WEAX containing Na+ and Ca2+ (1.0%) makes it possible to reduce 30% salt content in breads, which have implications in the large-scale production of low-salt/high-dietary fiber bread.


Assuntos
Pão/análise , Cálcio/análise , Fibras na Dieta/análise , Sódio na Dieta/análise , Fenômenos Químicos , Dieta Saudável , Cloreto de Sódio na Dieta/análise
11.
Nature ; 589(7843): 548-553, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33505038

RESUMO

Proxy reconstructions from marine sediment cores indicate peak temperatures in the first half of the last and current interglacial periods (the thermal maxima of the Holocene epoch, 10,000 to 6,000 years ago, and the last interglacial period, 128,000 to 123,000 years ago) that arguably exceed modern warmth1-3. By contrast, climate models simulate monotonic warming throughout both periods4-7. This substantial model-data discrepancy undermines confidence in both proxy reconstructions and climate models, and inhibits a mechanistic understanding of recent climate change. Here we show that previous global reconstructions of temperature in the Holocene1-3 and the last interglacial period8 reflect the evolution of seasonal, rather than annual, temperatures and we develop a method of transforming them to mean annual temperatures. We further demonstrate that global mean annual sea surface temperatures have been steadily increasing since the start of the Holocene (about 12,000 years ago), first in response to retreating ice sheets (12 to 6.5 thousand years ago), and then as a result of rising greenhouse gas concentrations (0.25 ± 0.21 degrees Celsius over the past 6,500 years or so). However, mean annual temperatures during the last interglacial period were stable and warmer than estimates of temperatures during the Holocene, and we attribute this to the near-constant greenhouse gas levels and the reduced extent of ice sheets. We therefore argue that the climate of the Holocene differed from that of the last interglacial period in two ways: first, larger remnant glacial ice sheets acted to cool the early Holocene, and second, rising greenhouse gas levels in the late Holocene warmed the planet. Furthermore, our reconstructions demonstrate that the modern global temperature has exceeded annual levels over the past 12,000 years and probably approaches the warmth of the last interglacial period (128,000 to 115,000 years ago).


Assuntos
Aquecimento Global/história , Temperatura Alta , Camada de Gelo , Estações do Ano , Cálcio/análise , Foraminíferos/química , Efeito Estufa/história , História Antiga , Magnésio/análise , Oceano Pacífico , Plâncton/química , Reprodutibilidade dos Testes , Água do Mar/análise , Água do Mar/química
12.
Nat Commun ; 12(1): 715, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514711

RESUMO

Coronary artery calcium is an accurate predictor of cardiovascular events. While it is visible on all computed tomography (CT) scans of the chest, this information is not routinely quantified as it requires expertise, time, and specialized equipment. Here, we show a robust and time-efficient deep learning system to automatically quantify coronary calcium on routine cardiac-gated and non-gated CT. As we evaluate in 20,084 individuals from distinct asymptomatic (Framingham Heart Study, NLST) and stable and acute chest pain (PROMISE, ROMICAT-II) cohorts, the automated score is a strong predictor of cardiovascular events, independent of risk factors (multivariable-adjusted hazard ratios up to 4.3), shows high correlation with manual quantification, and robust test-retest reliability. Our results demonstrate the clinical value of a deep learning system for the automated prediction of cardiovascular events. Implementation into clinical practice would address the unmet need of automating proven imaging biomarkers to guide management and improve population health.


Assuntos
Doenças Cardiovasculares/epidemiologia , Dor no Peito/diagnóstico , Vasos Coronários/diagnóstico por imagem , Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Idoso , Doenças Assintomáticas , Cálcio/análise , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/patologia , Dor no Peito/etiologia , Vasos Coronários/patologia , Feminino , Seguimentos , Fatores de Risco de Doenças Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco/métodos , Tomografia Computadorizada por Raios X
13.
Am J Med ; 134(3): 341-350.e1, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32822664

RESUMO

BACKGROUND: Coronary calcium is a marker of coronary atherosclerosis and established predictor of cardiovascular risk in general populations; however, there are limited studies examining its prognostic value among older adults (≥75 years) and even less regarding its utility in older males compared with females. Accordingly, we sought to examine the prognostic significance of both absolute and percentile coronary calcium scores among older adults. METHODS: The multicenter Coronary Artery Calcium Consortium consists of 66,636 asymptomatic patients without cardiovascular disease. Participants ages ≥75 were included in this study and stratified by sex. Multivariable Cox regression models were constructed to assess cardiovascular and all-cause mortality risk by Agatston coronary calcium scores and percentiles. RESULTS: Among 2,474 asymptomatic patients (mean age 79 years, 10.4-year follow-up), prevalence of coronary artery calcium was 92%. For both sexes, but in females more so than males, higher coronary calcium score and percentiles were associated with increased cardiovascular and all-cause mortality risk. Those at the lowest coronary calcium categories (0-9 and <25 percentile) had significantly lower risk of cardiovascular and all-cause mortality relative to the rest of the population. Multivariable analyses of traditional cardiovascular risk factors and coronary artery calcium variables revealed that age and coronary calcium were the strongest independent predictors for adverse outcomes. CONCLUSIONS: Both coronary artery calcium scores and percentiles are strongly predictive of cardiovascular and all-cause mortality among older adults, with greater risk-stratification among females than males. Both low coronary artery calcium scores 0-9 and <25th percentile define relatively low risk older adults.


Assuntos
Cálcio/análise , Doenças Cardiovasculares/mortalidade , Vasos Coronários/química , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Estudos de Coortes , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Masculino , Medição de Risco
14.
Arch Oral Biol ; 121: 104953, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33152593

RESUMO

OBJECTIVE: This study aimed to examine the potential changes in enamel surface of human smokers' teeth. MATERIALS AND METHODS: Forty extracted permanent, human, noncarious anterior teeth were used in this study. Half of these teeth were obtained from heavy smokers, while the other half of teeth were collected from nonsmokers (control teeth). The teeth were then subjected for scanning electron microscopic examination together with energy dispersive X ray and micro-hardness analysis to evaluate the qualitative and quantitative effect of smoking respectively. RESULTS: SEM of smokers' teeth showed variable degrees of destruction from small areas of demineralization as holes and pits to destruction and deterioration of the organizational pattern of the rod substance. Moreover, areas of defective remineralization were detected. The microhardness, calcium and phosphorus weight % significantly decreased whereas the Ca/P ratio was significantly increased. CONCLUSION: Cigarette smoking adversely affected the ultrastructure and mechanical properties of enamel and even hindered the normal remineralization process thus cigarette smoking cessation should be promoted in the dental office daily practices.


Assuntos
Fumar Cigarros/efeitos adversos , Esmalte Dentário/química , Esmalte Dentário/ultraestrutura , Cálcio/análise , Dureza , Humanos , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Fósforo/análise , Fumantes , Dente , Desmineralização do Dente
16.
Food Chem ; 344: 128639, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33229152

RESUMO

Clear acidic protein beverages have a niche market. Acidification of skim milk powder (SMP) dispersions to pH 3.0 using citric acid (CA) lowers turbidity but the dispersion remains translucent. The present study aimed at comparing physicochemical properties of 5% w/v SMP dispersions acidified to pH 3.0 using chelating gluconic acid (GA) and CA and non-chelating hydrochloric acid. GA was the most effective in reducing the dispersion turbidity to 394 NTU at pH 3.0, which was further reduced to 248 NTU after heating at 90 °C for 2 min resulting in transparent dispersions. The better chelating ability of GA than CA was supported by the higher extent of dissolved CCP in serum phase. The aggregation of dissociated caseins was not observed for the GA treatment based on transmission electron microscopy. The findings from this study may be used to produce clear casein-based protein beverages.


Assuntos
Quelantes/química , Gluconatos/química , Leite/química , Pós/química , Animais , Cálcio/análise , Caseínas/química , Ácido Cítrico/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Micelas , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Fósforo/análise
17.
Int J Artif Organs ; 44(3): 149-155, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32787606

RESUMO

INTRODUCTION: Heparin and citrate are commonly used anticoagulants in membrane/adsorption based extracorporeal liver support systems. However, anion exchange resins employed for the removal of negatively charged target molecules including bilirubin may also deplete these anticoagulants due to their negative charge. The aim of this study was to evaluate the adsorption of citrate by anion exchange resins and the impact on extracorporeal Ca2+ concentrations. METHODS: Liver support treatments were simulated in vitro. Citrate and Ca2+ concentrations were measured pre and post albumin filter as well as pre and post adsorbents. In addition, batch experiments were performed to quantify citrate adsorption. RESULTS: Pre albumin filter target Ca2+ concentrations were reached well with only minor deviations. Citrate was adsorbed by anion exchange resins, resulting in a higher Ca2+ concentration downstream of the adsorbent cartridges during the first hour of treatment. CONCLUSIONS: The anion exchange resin depletes citrate, leading to an increased Ca2+ concentration in the extracorporeal circuit, which may cause an increased risk of clotting during the first hour of treatment. An increase of citrate infusion during the first hour of treatment should therefore be considered to compensate for the adsorption of citrate.


Assuntos
Resinas de Troca Aniônica/farmacologia , Cálcio/análise , Ácido Cítrico/farmacologia , Heparina/farmacologia , Hipercalcemia , Falência Hepática , Membranas Artificiais , Desintoxicação por Sorção , Adsorção , Anticoagulantes/farmacologia , Bilirrubina/sangue , Bilirrubina/isolamento & purificação , Humanos , Hipercalcemia/etiologia , Hipercalcemia/prevenção & controle , Falência Hepática/sangue , Falência Hepática/terapia , Desintoxicação por Sorção/efeitos adversos , Desintoxicação por Sorção/instrumentação , Desintoxicação por Sorção/métodos , Propriedades de Superfície
18.
Int J Cardiovasc Imaging ; 37(1): 331-341, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32876901

RESUMO

To investigate the feasibility of quantifying the chemical composition of coronary artery plaque in terms of water, lipid, protein, and calcium contents using dual-energy computed tomography (CT) in a simulation study. A CT simulation package was developed based on physical parameters of a clinical CT scanner. A digital thorax phantom was designed to simulate coronary arterial plaques in the range of 2-5 mm in diameter. Both non-calcified and calcified plaques were studied. The non-calcified plaques were simulated as a mixture of water, lipid, and protein, while the calcified plaques also contained calcium. The water, lipid, protein, and calcium compositions of the plaques were selected to be within the expected clinical range. A total of 95 plaques for each lesion size were simulated using the CT simulation package at 80 and 135 kVp. Half-value layer measurements were made to make sure the simulated dose was within the range of clinical dual energy scanning protocols. Dual-energy material decomposition using a previously developed technique was performed to determine the volumetric fraction of water, lipid, protein, and calcium contents in each plaque. For non-calcified plaque, the total volume conservation provides the third constrain for three-material decomposition with dual energy CT. For calcified plaque, a fourth criterion was introduced from a previous report suggesting a linear correlation between water and protein contents in soft tissue. For non-calcified plaque, the root mean-squared error (RMSE) of the image-based decomposition was estimated to be 0.7%, 1.5%, and 0.3% for water, lipid, and protein contents, respectively. As for the calcified plaques, the RMSE of the 5 mm plaques were estimated to be 5.6%, 5.7%, 0.2%, and 3.1%, for water, lipid, calcium, and protein contents, respectively. The RMSE increases as the plaque size reduces. The simulation results indicate that chemical composition of coronary arterial plaques can be quantified using dual-energy CT. By accurately quantifying the content of a coronary plaque lesion, our decomposition method may provide valuable insight for the assessment and stratification of coronary artery disease.


Assuntos
Angiografia por Tomografia Computadorizada , Simulação por Computador , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Placa Aterosclerótica , Cálcio/análise , Angiografia por Tomografia Computadorizada/instrumentação , Angiografia Coronária/instrumentação , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Estudos de Viabilidade , Humanos , Lipídeos/análise , Imagens de Fantasmas , Valor Preditivo dos Testes , Proteínas/análise , Água/análise
19.
J Sci Food Agric ; 101(7): 2788-2798, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33135783

RESUMO

BACKGROUND: Germination promotes changes in the composition of seeds by providing potential nutritional and health benefits compared with unsprouted seeds. This study investigated the influence of germination on the bioaccessibility and bioavailability of calcium in brown flaxseed (BF) and golden flaxseed (GF). RESULTS: Germination did not influence the calcium levels of BF or GF, but the sprouted GF (SGF, 265.6 ± 12.9 mg) presented higher levels of calcium than the sprouted BF (SBF, 211.6 ± 3.20 mg). Tannin levels were similar among the groups (GF = 79.97 ± 3.49 mg; SGF = 78.81 ± 0.77 mg; BF = 81.82 ± 2.61 mg; SBF = 79.24 ± 4.58 mg), whereas phytate and oxalate levels decreased after germination. Germination reduced the phytate:calcium and oxalate:calcium molar ratios. In the in vitro study, germination increased calcium bioaccessibility (GF = 35.60 mg versus SGF = 41.45 mg; BF = 31.01 mg versus SBF = 38.84 mg). In the in vivo study, all groups present similar levels of urinary calcium (GF = 1.04 mg versus SGF = 2.06 mg; BF = 1.68 mg versus SBF = 1.35 mg) and fecal calcium (GF = 5.06 mg versus SGF = 6.14 mg; BF = 6.47 mg versus SBF = 8.40 mg). The calcium balance/day of the SBF group (37.97 mg) was smaller than the control group (47.22 mg). The germination maintained the plasma levels of calcium, phosphorus, creatinine, and alkaline phosphatase similar among the groups. No changes were observed in morphology and calcium levels of animal femurs. CONCLUSION: The germination reduced the antinutritional factor in both flaxseed varieties. Although there was an improvement in the in vitro bioaccessibility of calcium, the germination did not increase calcium absorption and balance in the animals, which may be due to the interaction with other compounds in the organism. © 2020 Society of Chemical Industry.


Assuntos
Cálcio/análise , Linho/química , Sementes/crescimento & desenvolvimento , Disponibilidade Biológica , Cálcio/metabolismo , Linho/crescimento & desenvolvimento , Linho/metabolismo , Germinação , Valor Nutritivo , Fósforo/análise , Fósforo/metabolismo , Sementes/química , Sementes/metabolismo , Taninos/análise , Taninos/metabolismo
20.
J Sci Food Agric ; 101(7): 3021-3029, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33205393

RESUMO

BACKGROUND: Mixtures of carrageenan and konjac gum are useful for specific applications in gel-based foods. Focusing on the changes of textural and structural properties, the effects of κ-carrageenan and konjac ratio and sucrose and Ca2+ concentrations on mixed gels were studied in this research. Furthermore, application of κ-carrageenan-konjac gum mixed gel to milk puddings was investigated. RESULTS: There was a better synergistic effect when the ratio of κ-carrageenan and konjac was 7:3. The mixed gel containing 10 g kg-1 κ-carrageenan-konjac gum was characterized by higher hardness, chewiness, adhesiveness and resilience and denser network structure. Besides, the addition of 5-10 wt% sucrose or 0.02 wt% Ca2+ could enhance the hardness, chewiness and adhesiveness of the mixed gel, as well as affording a denser network structure. For milk pudding, moderate hardness, chewiness and resilience could be obtained by adding 1.5 g kg-1 κ-carrageenan-konjac gum mixture. CONCLUSIONS: This research provides useful information for the formation of κ-carrageenan-konjac gum gel and its application in milk pudding. © 2020 Society of Chemical Industry.


Assuntos
Cálcio/análise , Carragenina/química , Laticínios/análise , Aditivos Alimentares/análise , Leite/química , Gomas Vegetais/química , Sacarose/análise , Animais , Bovinos , Manipulação de Alimentos , Géis/química , Dureza , Reologia
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