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1.
PLoS One ; 15(7): e0235135, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32628733

RESUMO

BACKGROUND: In patients on hemodialysis (HD), the various chemical elements in the dialysate may influence survival rates. In particular, calcium modifies mineral and bone metabolism and the vascular calcification rate. We studied the influence of the dialysate calcium concentration and the treatments prescribed for mineral bone disease (MBD) on survival. METHODS: All patients in REIN having initiated HD from 2010 to 2013 were classified according to their exposure to the different dialysate calcium concentrations in their dialysis unit. Data on the individual patients' treatments for MBD were extracted from the French national health database. Cox proportional hazard models were used to estimate mortality hazard ratios (HR) associated with time-dependent exposure to dialysate calcium concentrations and MBD therapies, adjusted for comorbidities, laboratory and technical data. RESULTS: Dialysate calcium concentration of 1.5 mmol/L was used by 81% of the dialysis centers in 2010 and in 83% in 2014. Most centers were using several formulas in up to 78% for 3 formulas in 2010 to 86% in 2014. In full adjusted Cox survival analyses, the percentage of calcium >1.5 mmol/L and <1.5 mmol/l by center and the number of formula used per center were not associated with survival. Depending on the daily dose used, the MBD therapies were associated with survival improvement for calcium, native vitamin D, active vitamin D, sevelamer, lanthanum and cinacalcet in the second and third tertiles of dose. CONCLUSION: No influence of the dialysate calcium concentration was evidenced on survival whereas all MBD therapies were associated with a survival improvement depending on the daily dose used.


Assuntos
Osso e Ossos/efeitos dos fármacos , Cálcio/análise , Soluções para Hemodiálise/análise , Sistema de Registros , Diálise Renal , Insuficiência Renal Crônica/terapia , Idoso , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/fisiopatologia , Osso e Ossos/metabolismo , Osso e Ossos/fisiopatologia , Calcinose/epidemiologia , Calcinose/metabolismo , Calcinose/fisiopatologia , Cálcio/administração & dosagem , Cálcio/metabolismo , Cinacalcete/análise , Feminino , França/epidemiologia , Soluções para Hemodiálise/administração & dosagem , Soluções para Hemodiálise/química , Humanos , Lantânio/análise , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/mortalidade , Insuficiência Renal Crônica/fisiopatologia , Sevelamer/análise , Vitamina D/análise , Vitamina D/metabolismo
2.
Chemosphere ; 251: 126253, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32443229

RESUMO

We developed a simple method of analyzing the strontium (Sr) and calcium (Ca) content of intact eggshell samples in support of a broader study of how dietary Sr uptake impacts waterfowl eggshell quality. We used wavelength dispersive - x-ray fluorescence spectrometry (WD-XRF) to analyze eggshell pieces ranging in size from ∼6-mm2 fragments to intact half-shells. We verified this approach on a subset of reference shells by subjecting the same region and volume of shell material from which x-ray signals were measured to analysis by inductively-coupled plasma mass spectrometry (ICP-MS). An analysis of the sources of analytical uncertainty yielded total internal error estimates of ±0.3 and 5% relative for Ca and Sr, respectively, on the basis of which the chemistry of intact shell material analyzed by WD-XRF in this study is compared. The total external errors associated with the WD-XRF results of this study in relation to certified reference material (National Institute of Standards and Technology [NIST] 1400 [a bone ash]) are ±9 and 13.5% relative for Ca and Sr, respectfully (95% CL). Our results demonstrate this method is acceptably accurate and precise for many wildlife management applications. WD-XRF analysis is a quick and inexpensive alternative to traditional methods for determining eggshell Sr and Ca that require acid digestion, allowing for generation of larger datasets that might otherwise be cost-prohibitive, while preserving sample material intact.


Assuntos
Cálcio/análise , Casca de Ovo/química , Espectrometria por Raios X/métodos , Animais , Cálcio na Dieta , Minerais , Estrôncio/análise
3.
Nat Methods ; 17(7): 694-697, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32451475

RESUMO

Femtosecond lasers at fixed wavelengths above 1,000 nm are powerful, stable and inexpensive, making them promising sources for two-photon microscopy. Biosensors optimized for these wavelengths are needed for both next-generation microscopes and affordable turn-key systems. Here we report jYCaMP1, a yellow variant of the calcium indicator jGCaMP7 that outperforms its parent in mice and flies at excitation wavelengths above 1,000 nm and enables improved two-color calcium imaging with red fluorescent protein-based indicators.


Assuntos
Cálcio/análise , Corantes Fluorescentes/química , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Animais , Drosophila , Feminino , Lasers , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Imagem Molecular , Córtex Somatossensorial/química
4.
J Dairy Sci ; 103(6): 4965-4974, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32253034

RESUMO

We investigated the effect of seasonal variations on the acid gelation properties of bovine milk in a seasonal-calving New Zealand herd for 2 full milking seasons. We tested the formation of acid gels in 2 milk systems: unstandardized skim milk and standardized whole milk (4.6% protein, 4.0% fat). For unstandardized skim milk, late-season milk acid gels had a longer gelation time and a lower gelation pH than early- and mid-season milk acid gels, but we found no consistent seasonal variation in the final storage modulus. For standardized milk, late-season milk had the most inferior acid gelation properties during the year, including the lowest final storage modulus, the lowest gelation pH, and the longest gelation time. Standardization alleviated but did not eliminate the prolonged gelation time of late-season milk. These results indicated that the physicochemical properties of seasonal milk contributed greatly to its acid gelation, independent of differences in protein content. Standardization was not adequate to stabilize the acid gelation properties of late-season milk. Desirable acid gelation properties correlated with lower glycosylated κ-casein content, lower ß-lactoglobulin:α-lactalbumin ratio, lower extent of whey protein-casein micelle association, and lower total calcium and ionic calcium content. We discuss the possible effects of the correlating variables on the acid gelation properties of seasonal milk. Natural variations in the glycosylation degree of κ-casein might play an important role in acid gel structural development by altering the electrostatic and hydrophobic interactions among the milk proteins.


Assuntos
Leite/química , Estações do Ano , Animais , Cálcio/análise , Caseínas/análise , Bovinos , Qualidade dos Alimentos , Géis/química , Interações Hidrofóbicas e Hidrofílicas , Lactoglobulinas/análise , Micelas , Proteínas do Leite/análise , Nova Zelândia , Proteínas do Soro do Leite/análise
5.
Acta Cir Bras ; 35(1): e202000101, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32159587

RESUMO

Solid organ transplantation is a very complex process, in which the storage of the graft in a preservation solution is mandatory in order to extend ischemic times and contain further damage. The condition in which the organ is transplanted is critical for the outcome of the organ recipient. The recent emergence of generic versions of organ preservation solutions (solutions with the same composition and under the same legislation as the original versions, but with different brands) compelled us to study whether the standards are maintained when comparing the original and its generic counterpart. Along these lines, we discuss and comment on some aspects concerning this issue of general interest in the organ transplantation field.


Assuntos
Glutationa/química , Soluções para Preservação de Órgãos/química , Transplante de Órgãos/métodos , Cálcio/análise , Humanos , Soluções para Preservação de Órgãos/normas , Temperatura , Fatores de Tempo
6.
Braz J Med Biol Res ; 53(3): e8761, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32159612

RESUMO

Nitric oxide (NO) inhibition by high-dose NG-nitro-L-arginine methyl ester (L-NAME) is associated with several detrimental effects on the cardiovascular system. However, low-dose L-NAME increases NO synthesis, which in turn induces physiological cardiovascular benefits, probably by activating a protective negative feedback mechanism. Aerobic exercise, likewise, improves several cardiovascular functions in healthy hearts, but its effects are not known when chronically associated with low-dose L-NAME. Thus, we tested whether the association between low-dose L-NAME administration and chronic aerobic exercise promotes beneficial effects to the cardiovascular system, evaluating the cardiac remodeling process. Male Wistar rats were randomly assigned to control (C), L-NAME (L), chronic aerobic exercise (Ex), and chronic aerobic exercise associated to L-NAME (ExL). Aerobic training was performed with progressive intensity for 12 weeks; L-NAME (1.5 mg·kg-1·day-1) was administered by orogastric gavage. Low-dose L-NAME alone did not change systolic blood pressure (SBP), but ExL significantly increased SBP at week 8 with normalization after 12 weeks. Furthermore, ExL promoted the elevation of left ventricle (LV) end-diastolic pressure without the presence of cardiac hypertrophy and fibrosis. Time to 50% shortening and relaxation were reduced in ExL, suggesting a cardiomyocyte contractile improvement. In addition, the time to 50% Ca2+ peak was increased without alterations in Ca2+ amplitude and time to 50% Ca2+ decay. In conclusion, the association of chronic aerobic exercise and low-dose L-NAME prevented cardiac pathological remodeling and induced cardiomyocyte contractile function improvement; however, it did not alter myocyte affinity and sensitivity to intracellular Ca2+ handling.


Assuntos
Cálcio/análise , Inibidores Enzimáticos/farmacologia , Contração Miocárdica/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Adiposidade , Animais , Peso Corporal/fisiologia , Inibidores Enzimáticos/administração & dosagem , Hemodinâmica , Masculino , Modelos Animais , Atividade Motora/fisiologia , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/fisiologia , NG-Nitroarginina Metil Éster/administração & dosagem , Óxido Nítrico Sintase/metabolismo , Ratos Wistar , Pressão Ventricular/efeitos dos fármacos
7.
PLoS One ; 15(3): e0223937, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32168346

RESUMO

Panicum maximum Jacq. 'Mombaça' (Guinea grass) is a C4 forage grass widely used in tropical pastures for cattle feeding. In this study, we evaluated the isolated and combined effects of warming and elevated CO2 concentration [CO2] during summer on nutrient content, nutrient accumulation, nutrient use efficiency and growth of P. maximum under field conditions. Field temperature and [CO2] were controlled by temperature free-air controlled enhancement and free-air CO2 enrichment systems, respectively. We tested two levels of canopy temperature: ambient temperature (aT) and 2°C above ambient temperature (eT), as well as two levels of atmospheric [CO2]: ambient [CO2] (aCO2) and 200 ppm above ambient CO2 (eCO2). The experiment was established in a completely randomized design with four replications, in a 2×2 factorial scheme. After pasture establishment, plants were exposed to the treatments during 30 days, with evaluations at 9, 16, 23 and 30 days after the treatments started. Results were dependent on the time of the evaluation, but in the last evaluation (beginning of the grazing), contents of N, K, Mg and S did not change as a function of treatments. However, P decreased as a function of warming under both levels of [CO2], and Ca increased under [eCO2] combined with warming. There was an increase in root dry mass under warming treatment. Combined treatment increased N, Ca and S accumulation without a corresponding increase in the use efficiency of these same nutrients, indicating that the fertiliser dose should increase in the next decades due to climate change. Our short-term results in young and well fertilized pasture suggest that under the combination of [eCO2] and eT conditions, P. maximum productivity will increase and the nutritional requirement for N, Ca and S will also increase.


Assuntos
Dióxido de Carbono/farmacologia , Temperatura Alta , Nutrientes/análise , Panicum/crescimento & desenvolvimento , Ração Animal , Animais , Cálcio/análise , Dióxido de Carbono/química , Bovinos , Mudança Climática , Nitrogênio/análise , Concentração Osmolar , Panicum/efeitos dos fármacos , Solo/química , Água
8.
BMC Public Health ; 20(1): 383, 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32204706

RESUMO

BACKGROUND: Explanation of the pathogenesis and treatment of autism spectrum disorders (ASD) is one of the most significant challenges for scientists today. It is believed that a major pathogenetic factor of this condition is epigenetic changes caused by environmental factors, including toxic metals (cadmium (Cd), lead (Pb), mercury (Hg), aluminium (Al), and arsenic (As)). The nervous system may also be affected by deficiencies of both micro- and macroelements (e.g. calcium (Ca), zinc (Zn)). The aim of the study was to analyze the concentrations of Pb, As, and Ca in the hair of children with ASD and a control group. METHODS: The materials for the study comprised hair samples collected from 30 children diagnosed with ASD (case group) and 30 children randomly selected from the general population of Bialystok and surrounding region (control group). Concentrations of Pb, As, and Ca were tested with electron microscopy scanning method. Next, the content of the analyzed elements in the hair was assessed as well as their impact on autism development in the children and the mutual interactions between them. The obtained results were statistically analyzed with Statistica PL 12.5., using the Mann-Whitney U test, and Spearman correlation coefficient. RESULTS: Mean Ca level in the hair of the case group was lower than the mean level of this element in the control group. Mean As and Pb concentration in the hair of children with ASD was statistically significantly higher than the mean concentration of this element in the hair of children without neurological disorders. Statistically insignificant weak positive correlations between Ca and As content and negative between Ca and Pb in the hair of children from the case group were noted. Also, statistically significant mean positive correlations between Pb and As were observed. CONCLUSIONS: In this small study, according to the observations, children diagnosed with ASD suffer from Ca deficiency and toxic metal overload (As and Pb). These abnormalities may play the main role, as an environmental factor, in the pathogenesis of the analyzed disorder.


Assuntos
Arsênico/análise , Transtorno do Espectro Autista/epidemiologia , Cálcio/análise , Cabelo/química , Chumbo/análise , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Polônia/epidemiologia , População Urbana/estatística & dados numéricos
9.
Ann Agric Environ Med ; 27(1): 19-28, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32208575

RESUMO

INTRODUCTION: Osteoporosis, a disease associated with ovarian hormone deficiency following menopause, is the most common cause of age-related bone loss. Although an optimal intake of Ca is vital - both bone accretion during growth and maintenance in adult life - a great percentage of the population consumes far below the recommended amounts of this mineral. On the other hand, there are evidences that fructans enhance not only Ca absorption, but bone calcium as well. OBJECTIVE: In the knowledge that estrogen deficiency and insufficient Ca in the diet during postmenopause cause serious problems with resultant osteoporosis, the aim of this study is to assess the effects of a diet enriched in fructan-containing sources alone, or in the "strawberry matrix", on the structure of bone in OVX rats under calcium hypoalimentation. MATERIAL AND METHODS: Experimental animals were female Wistar rats, sham-operated or ovariectomized. The treatment with Ca-restricted diets also contained one of the sources of fructan (Jerusalem artichoke, yacon, Beneo Orafti Synergy1), in the amount providing 8% of fructans. Femur architecture of rats was assessed by tomography and Ca content by the AAS method. RESULTS: Ovariectomy led to a significant decrease in femoral Ca content, total mineral content and bone density of rats. This study shows that a diet containing inulin-type fructan (especially as a component of strawberry product) improved bone quality (i.e. increase in Ca content in femur, total density in middle part of bone, as well as decrease of endosteal circumference) in OVX rats under calcium hypoalimentation. CONCLUSIONS: These findings suggest that a fructan-enriched diet could be potentially useful for postmenopausal osteoporosis. It is important to determine an optimal dietary level of fructan with the long-term goal of developing a dietary strategy in osteoporosis prevention.


Assuntos
Cálcio/análise , Fêmur/efeitos dos fármacos , Fragaria , Frutanos/farmacologia , Animais , Asteraceae , Densidade Óssea/efeitos dos fármacos , Cálcio/deficiência , Dieta , Feminino , Fêmur/anatomia & histologia , Fêmur/química , Osteoporose/prevenção & controle , Ovariectomia , Ratos Wistar
10.
Food Chem ; 320: 126639, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32213423

RESUMO

Laser-induced breakdown spectroscopy (LIBS), Fourier transform mid-infrared (FT-IR) and Raman spectroscopy combined with chemometrics were investigated to quantify calcium (Ca) content in infant formula powder (INF). INF samples (n = 51) with calcium content levels (ca. 6.5-30 mg Ca/100 kJ) were prepared in accordance with the guidelines of Commission Directive 2006/125/EC. Atomic absorption spectroscopy (AAS) was used as the reference method for Ca content determination. To predict Ca content in INF samples, partial least squares regression (PLSR) models that developed based on LIBS, Raman and FT-IR spectral data, respectively. The model developed using LIBS data achieved the best performance for the quantification of Ca content in INF (R2 (cross-validation (CV))-0.99, RMSECV-0.29 mg/g; R2 (prediction (P))-1, RMSEP-0.63 mg/g). PLSR models that developed based on data fusion of Raman and FT-IR spectral features obtained the second best performance (R2CV-0.97, RMSECV-0.38 mg/g; R2P-0.97, RMSEP-0.36 mg/g). This study demonstrated the potential of LIBS, FT-IR and Raman spectroscopy to accurately quantify Ca content in INF.


Assuntos
Cálcio na Dieta/análise , Cálcio/análise , Fórmulas Infantis/química , Análise de Fourier , Humanos , Lactente , Análise dos Mínimos Quadrados , Espectrofotometria Atômica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
11.
Curr Urol Rep ; 21(1): 6, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32016596

RESUMO

PURPOSE OF REVIEW: The role of the mineral constituents in water and their role in kidney stone disease (KSD) have been a long-standing subject of debate. The aim of our systematic review was to evaluate the relevance of different types of water in stone disease. RECENT FINDINGS: Studies to date have had varying results regarding the importance of hardness of water which is mostly determined by its calcium content. Other elements including magnesium and bicarbonate also play a crucial role in prevention of renal stones. Patients with stone disease are provided varying advice due to a lack of consensus on the types of water recommended. Increased fluid intake prevents stone formation. Our review of the literature suggests that hard water and bottled mineral water might be helpful for calcium stone formers. High calcium content in them leads to hypercalciuria; however, other factors also influence stone formation and the overall impact seems to be a reduction in calcium stone formation. The mineral content varies across different water types but high magnesium and bicarbonate content in water is also recommended for kidney stone patients.


Assuntos
Cálcio/análise , Água Potável , Cálculos Renais/prevenção & controle , Águas Minerais/uso terapêutico , Bicarbonatos/análise , Ingestão de Líquidos , Água Potável/química , Humanos , Cálculos Renais/etiologia , Cálculos Renais/terapia , Magnésio/análise , Águas Minerais/análise
12.
Medicina (B Aires) ; 80(1): 87-90, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-32044746

RESUMO

Gitelman syndrome is one of the salt losing tubulopathies. Hypokalemia and hypomagnesemia appear in the setting of the partial blockade of salt absorption in the distal tubule. We conducted a descriptive study of a case series of five patients with Gitelman syndrome (4 women, from 28 to 85 years) in our institution, between the years 2004 and 2015. The most frequent form of diagnosis in our series was by laboratory finding. The only acknowledged clinical symptom was malaise. Regarding laboratory findings, the mean potassemia was of 2.5 ± 0.5 mmol/l, with a minimum value of 2.1 mmol/l. Additionally, the serum magnesium value was of 1.3 ± 0.3 mg/dl. In conclusion, we observed that the forms of presentation consist of biochemical alterations with or without nonspecific manifestations, which currently represents the greatest diagnostic difficulty and reinforces the importance to achieve a timely diagnosis, especially in young patients with critical serum potassium values.


Assuntos
Síndrome de Gitelman/diagnóstico , Síndrome de Gitelman/terapia , Adulto , Idoso de 80 Anos ou mais , Astenia/diagnóstico , Cálcio/análise , Feminino , Síndrome de Gitelman/metabolismo , Humanos , Magnésio/análise , Masculino , Pessoa de Meia-Idade , Potássio/análise
13.
J Agric Food Chem ; 68(10): 3277-3285, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32054265

RESUMO

5-Hydroxy-l-tryptophan (5-HTP) is the primary product that converts l-tryptophan into 5-hydroxytryptamine by a rate-limiting enzyme. Our previous study found that 5-HTP could promote the intracellular calcium level in goat mammary epithelial cells (GMECs). Herein, first, dairy goats were injected with 5-HTP or saline daily from 7 days before delivery, and the calcium level in colostrum of 5-HTP-injected goats was significantly higher than that of saline-injected goats. Moreover, miR-99a-3p expression was significantly increased after 5-HTP treatment from transcriptome sequencing analysis and quantitative real-time polymerase chain reaction. In addition, it was found that ATP2B1 is one of the target genes of miR-99a-3p predicted by bioinformatic methods, which plays a crucial role in the maintenance of intracellular calcium homeostasis of mammary epithelial cells. Next, we confirmed that miR-99a-3p could increase the intracellular calcium level via decreasing ATP2B1 in GMECs. Taken together, we draw the conclusion that 5-HTP promotes the calcium level in colostrum possibly by increasing intracellular calcium of mammary epithelial cells induced by the miR-99a-3p/ATP2B1 axis.


Assuntos
5-Hidroxitriptofano/administração & dosagem , Cálcio/metabolismo , Células Epiteliais/metabolismo , Cabras/metabolismo , Glândulas Mamárias Animais/metabolismo , MicroRNAs/genética , Leite/química , Animais , Cálcio/análise , Células Epiteliais/efeitos dos fármacos , Feminino , Cabras/genética , Lactação , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/efeitos dos fármacos , MicroRNAs/metabolismo , Leite/metabolismo
14.
Chemosphere ; 242: 125289, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896204

RESUMO

Selenium (Se) and zinc (Zn) are essential microelements for humans with crucial biological functions. In this study, we determined Se and Zn concentrations in soils and rice grains on Hainan Island and investigated how their spatial distributions are related to soil mineral elements, topography, and vegetation coverage. Overall, the concentrations of Se and Zn in soils were higher than the background values for Chinese soil; the Se concentrations in rice grains were higher than the threshold value for Se deficiency in grains, but Zn concentrations were lower than the proposed critical concentration. Both Spearman's correlation and stepwise regression analysis showed that the concentrations of soil Fe and Ca significantly affected soil Se and Zn: a difference of 1 g kg-1 in soil Fe changed soil Se by 2.820 µg kg-1 and soil Zn by 0.785 mg kg-1, respectively, while a difference of 1 g kg-1 in soil Ca changed soil Se by 3.249 µg kg-1 and soil Zn by 0.356 mg kg-1, respectively. For rice grains, Se and Zn concentrations decreased with increasing elevation; every 100 m increase in elevation could decrease Se by 0.022 mg kg-1 and Zn by 0.912 mg kg-1. Moreover, the impact of Fe and Ca on soil Zn was relatively strong in the northeast region, while the influence of elevation on rice grain Se was more significant in the central region. The findings contribute to a better understanding of factors driving the distribution of Se and Zn in soils and crops.


Assuntos
Grão Comestível/química , Monitoramento Ambiental/métodos , Oryza/química , Selênio/análise , Solo/química , Zinco/análise , Altitude , Cálcio/análise , China , Humanos , Ferro/análise , Ilhas , Análise de Regressão , Análise Espacial
15.
Int J Mol Sci ; 21(1)2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31906530

RESUMO

Fused deposit modeling (FDM) 3D printing technology cannot generate scaffolds with high porosity while maintaining good integrity, anatomical-surface detail, or high surface area-to-volume ratio (S/V). Solvent casting and particulate leaching (SCPL) technique generates scaffolds with high porosity and high S/V. However, it is challenging to generate complex-shaped scaffolds; and solvent, particle and residual water removal are time consuming. Here we report techniques surmounting these problems, successfully generating a highly porous scaffold with the anatomical-shape characteristics of a human femur by polylactic acid polymer (PLA) and PLA-hydroxyapatite (HA) casting and salt leaching. The mold is water soluble and is easily removable. By perfusing with ethanol, water, and dry air sequentially, the solvent, salt, and residual water were removed 20 fold faster than utilizing conventional methods. The porosities are uniform throughout the femoral shaped scaffold generated with PLA or PLA-HA. Both scaffolds demonstrated good biocompatibility with the pre-osteoblasts (MC3T3-E1) fully attaching to the scaffold within 8 h. The cells demonstrated high viability and proliferation throughout the entire time course. The HA-incorporated scaffolds demonstrated significantly higher compressive strength, modulus and osteoinductivity as evidenced by higher levels of alkaline-phosphatase activity and calcium deposition. When 3D printing a 3D model at 95% porosity or above, our technology preserves integrity and surface detail when compared with FDM-generated scaffolds. Our technology can also generate scaffolds with a 31 fold larger S/V than FDM. We have developed a technology that is a versatile tool in creating personalized, patient-specific bone graft scaffolds efficiently with high porosity, good scaffold integrity, high anatomical-shaped surface detail and large S/V.


Assuntos
Materiais Biocompatíveis/química , Osteoblastos/química , Impressão Tridimensional , Engenharia Tecidual/métodos , Tecidos Suporte/química , Materiais Biocompatíveis/síntese química , Cálcio/análise , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Força Compressiva , Durapatita/química , Fêmur , Humanos , Teste de Materiais , Osteoblastos/enzimologia , Osteoblastos/metabolismo , Perfusão , Poliésteres/química , Porosidade , Tecidos Suporte/efeitos adversos
16.
Curr Diabetes Rev ; 16(8): 869-873, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31987023

RESUMO

BACKGROUND: Cardiovascular disease (CVD), the main macro vascular complication of type 2 diabetes (T2D), increases the risk of death significantly in patients with T2D. INTRODUCTION: Most of the patients with T2D do not have obvious CVD symptoms. Due to the paucity of data, CVD screening in asymptomatic patients with T2D remains highly controversial. METHODS: This has driven a panel of experts to establish a novel consensus on how to approach patients with T2D at high CVD risk. The panel formulated a stepwise algorithm by which patients with T2D undergo initial risk stratification into low, intermediate and high risk using the ASCVD calculator. In patients with intermediate risk, coronary artery calcium measurement is used to further stratify those patients into new low and high-risk categories. RESULTS AND CONCLUSION: The panel recommends using standard diabetes care in low risk patients and using SGLT2 inhibitors and GLP1 agonists with cardio protective effect, on top of standard care, in high risk individuals.


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Algoritmos , Cálcio/análise , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Consenso , Vasos Coronários/diagnóstico por imagem , Diabetes Mellitus Tipo 2/complicações , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Humanos , Programas de Rastreamento , Seleção de Pacientes , Substâncias Protetoras/uso terapêutico , Medição de Risco , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Tomografia Computadorizada por Raios X
17.
Neuron ; 105(2): 322-333.e5, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31810837

RESUMO

Innate behaviors involve both reflexive motor programs and enduring internal states, but how these responses are coordinated by the brain is not clear. In Drosophila, male-specific P1 interneurons promote courtship song, as well as a persistent internal state that prolongs courtship and enhances aggressiveness. However, P1 neurons themselves are not persistently active. Here, we identify pCd neurons as persistently active, indirect P1 targets that are required for P1-evoked persistent courtship and aggression. Acute activation of pCd neurons alone is inefficacious but enhances and prolongs courtship or aggression promoted by female cues. Brief female exposure induces a persistent increase in male aggressiveness, an effect abrogated by interruption of pCd activity. pCd activity is not sufficient but necessary for persistent physiological activity, implying an essential role in a persistence network. Thus, P1 neurons coordinate both command-like control of courtship song and a persistent internal state of social arousal mediated by pCd neurons.


Assuntos
Agressão/fisiologia , Corte , Drosophila/citologia , Drosophila/fisiologia , Interneurônios/fisiologia , Neurônios/fisiologia , Animais , Animais Geneticamente Modificados , Cálcio/análise , Feminino , Masculino
18.
Food Chem Toxicol ; 135: 110974, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31743745

RESUMO

During tea preparation mineral elements are extracted from the dried leaves of tea (Camellia sinensis (L.) Kuntze) plants into the solution. Micro-particle induced X-ray emission was employed to investigate the spatial distribution of magnesium (Mg), calcium (Ca) and manganese (Mn) in the young and old leaves of tea plants grown in the absence and presence of aluminium (Al) in the substrate. Results revealed that in tea leaves the largest concentrations of Mg occurred in the epidermis, of Ca in oxalate crystals and of Mn in epidermis and oxalate crystals; there was a leaf-age effect on tissue-specific concentrations of Mg, Ca and Mn with all tissues of old leaves containing larger concentrations of Mg, Ca and Mn than young leaves; supplementation of substrate with Al reduced concentrations of Mg, Ca and Mn in the old leaves, and a link between the distribution of Mg, Ca and Mn in the tea leaves with the extraction efficiencies of these elements into the tea was possible. We conclude that old leaves of tea plants cultivated under conditions of low Al availability will have the largest concentrations of Mg, Ca and Mn and may represent most acceptable ingredient for the preparation of tea.


Assuntos
Cálcio/metabolismo , Camellia sinensis/química , Magnésio/metabolismo , Manganês/metabolismo , Folhas de Planta/química , Chá/química , Alumínio/metabolismo , Cálcio/análise , Magnésio/análise , Manganês/análise , Extração em Fase Sólida , Espectrometria por Raios X , Distribuição Tecidual
19.
Environ Geochem Health ; 42(1): 159-171, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31111334

RESUMO

This study was aimed at assessment of strontium and calcium mobility in soils and their accumulation with plants in the areas endemic for Kashin-Beck disease in Eastern Transbaikalia. The strontium and calcium mobility levels were determined using the method of sequential chemical extraction for 7 samples of meadow soils collected from the endemic region and 7 soil samples taken from conditionally control sites. To measure the Ca and Sr levels in the soil and plant samples, XRF analysis and AAS were used. The increased strontium level in the meadow soils of the endemic areas is accompanied by the element's higher mobility. The highest strontium yield was observed in the course of soil extraction using 1 M ammonium acetate, while the soils taken from the control sites gave lower amounts of the trace element. Furthermore, there is a positive correlation between the amount of the strontium extracted and its content in plants (r = + 0.86 - 0.98). At the sequential chemical extraction of calcium from the soils using the above method, the calcium yield was maximal in the ammonium acetate fraction (background sites) and in ammonium acetate and 6 M HCl fractions (endemic areas). The correlation between the amount of the calcium extracted in 1 M ammonium acetate and the macroelement levels found in plants was + 0.968. In addition, a peculiarly high accumulation of strontium in various willow species as compared to other meadow plants was revealed for the first time ever. Thus, the work introduces new data into the trace element biogeochemistry and environmental monitoring.


Assuntos
Cálcio/análise , Doença de Kashin-Bek , Plantas/metabolismo , Solo/química , Estrôncio/análise , Bioacumulação , Cálcio/farmacocinética , Monitoramento Ambiental/métodos , Pradaria , Humanos , Plantas/química , Sibéria , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética , Estrôncio/farmacocinética
20.
Environ Geochem Health ; 42(3): 769-780, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30852732

RESUMO

In recent years, acid rain had a serious negative impact on the leaching behavior of industrial waste residue. Researches were mainly focused on the environmental hazards of heavy metal in the leachate, but ignored the effects of heavy metal speciation on the stability of waste residue in the subsequent stabilization process. In this study, the unstable calcium-arsenic compounds in the arsenic calcium residue were firstly removed by leaching process; subsequently, the crystallization agent was added to treat the remaining calcium-arsenic mixture. The results of the leaching process demonstrated that the decrease in particle size and pH value directly affected the increase in the cumulative leaching amount of arsenic, and the cumulative leaching ratio reached 1.55%. In addition, the concentration of arsenic decreased from 3583 to 49.1 mg L-1. After the crystallization process, the arsenic concentration was lower than the limit value of Identification Standards for Hazardous Wastes (GB 5085.3-2007). The SEM analysis showed the bulk structures, and XRD pattern confirmed that they were the stable compounds. Moreover, the result of XRD and SEM illustrated that acid concentration, chloride ions and sulfate ions were contributed to the transformation and growth of stable calcium arsenate compounds. Therefore, effective control of the acidity of acid rain, the type of anions in acid rain, and the particle size of residues would contribute to adjusting the arsenic speciation to be more stable. The leaching-crystallization process was of great significance to improve the stability of the arsenic-containing residue.


Assuntos
Chuva Ácida , Arseniatos/química , Arsênico/química , Compostos de Cálcio/química , Chuva Ácida/análise , Arsênico/análise , Cálcio/análise , Cálcio/química , Cristalização , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Difração de Raios X
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