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1.
Crit Rev Food Sci Nutr ; 63(21): 5290-5305, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34933633

RESUMO

Non-melanoma skin cancer (NMSC) is the most common cancer among white-skinned people. The main environmental risk factor for all types of skin cancer is ultraviolet (UV) exposure to the sun. However, significant modifiable risk factors, such as diet, have been studied about NMSC risk. Several original studies have been conducted on the link between various dietary components and the risk of NMSC in the past decade, but have not been systematically reviewed. This review focuses on the potential impact of dietary components in the prevention of NMSC and evaluates the findings of epidemiologic evidence for dietary factors. We conducted a systematic search of three databases, including Scopus, ISI Web of Science, and PubMed, to identify relevant epidemiological studies published between 2000 and July 6, 2021. Finally, forty-three articles were included. Because of the inherent limitations of epidemiological studies, no definitive conclusions can be drawn; however, the links between folate, citrus, caffeine, and alcohol with BCC are notable; thus, high dietary folate intake, as well as citrus and alcohol consumption, are associated with an increased risk of basal cell carcinoma (BCC), whereas caffeine is associated with a lower risk. More research is required to reach a definitive conclusion.


Assuntos
Carcinoma Basocelular , Neoplasias Cutâneas , Humanos , Cafeína , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/prevenção & controle , Carcinoma Basocelular/epidemiologia , Carcinoma Basocelular/etiologia , Carcinoma Basocelular/prevenção & controle , Fatores de Risco , Dieta , Ácido Fólico , Estudos Epidemiológicos
2.
Crit Rev Food Sci Nutr ; 62(28): 7760-7772, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33951994

RESUMO

We aimed to examine the association between adherence to plant-based diets (PBDs) and the risk of mortality among the general population. Relevant investigations were identified through PubMed, Scopus, Embase, and ISI Web of Knowledge. Data were pooled using a random-effects or a fixed-effects model. Twelve prospective cohort studies with 42,697 deaths among 508,861 participants were included. The hazard ratios (HRs) for the highest compared to the lowest category of adherence to the PBDs were 0.90 (95% confidence interval [CI]: 0.82, 0.99; I2 = 91%, n = 12) for all-cause and 0.77 (95% CI: 0.70, 0.86; I2 = 36%, n = 8) for coronary heart disease (CHD) mortality. Among PBDs subtypes, there was an inverse association between healthy plant-based 0.92 (95% CI: 0.88, 0.96; I2 = 0%, n = 2), Pesco-vegetarian 0.81 (95% CI: 0.70, 0.92; I2 = 0%, n = 2), and Pro-vegetarian 0.74 (95% CI: 0.55, 0.88; I2 = 61.2%, n = 2) diets and the risk of all-cause mortality. A vegetarian diet was also associated with lower risk of mortality due to cardiovascular 0.92 (95% CI: 0.85, 0.99; I2 = 0%, n = 5) and CHD 0.76 (95% CI: 0.68, 0.85; I2 = 35%, n = 7). Our findings show the potential protective role of PBDs against chronic disease mortality. As there were certain limitations in some of the studies included in this systematic review and meta-analysis, further research is necessary to confirm our findings.


Assuntos
Doenças Cardiovasculares , Dieta , Doenças Cardiovasculares/epidemiologia , Estudos de Coortes , Dieta Vegetariana , Humanos , Estudos Prospectivos , Vegetarianos
3.
J Chem Phys ; 157(8): 084104, 2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-36049992

RESUMO

Resonance Raman spectroscopy has long been established as one of the most sensitive techniques for detection, structure characterization, and probing the excited-state dynamics of biochemical systems. However, the analysis of resonance Raman spectra is much facilitated when measurements are accompanied by Density Functional Theory (DFT) calculations that are expensive for large biomolecules. In this work, resonance Raman spectra are therefore computed with the Density Functional Tight-Binding (DFTB) method in the time-dependent excited-state gradient approximation. To test the accuracy of the tight-binding approximations, this method is first applied to typical resonance Raman benchmark molecules, such as ß-carotene, and compared to results obtained with pure and range-separated exchange-correlation functionals. We then demonstrate the efficiency of the approach by considering a computationally challenging heme variation. Overall, we find that the vibrational frequencies and excited-state properties (energies and gradients) that are needed to simulate the spectra are reasonably accurate and suitable for interpretation of experiments. We can therefore recommend DFTB as a fast computational method to interpret resonance Raman spectra.


Assuntos
Teoria Quântica , Vibração , Simulação por Computador , Teoria da Densidade Funcional , Análise Espectral Raman
4.
Br J Nutr ; 124(8): 832-843, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-32406342

RESUMO

We aimed to study dietary patterns in association with the relative expression levels of PPAR-γ, vascular endothelial growth factor-A (VEGF-A) and hypoxia-inducible factor-1α (HIF-1α) in women with benign breast disease (BBD). The study design was combinative, included a case-series and case-control compartments. Initially, eligible BBD patients (n 77, aged 19-52 years old) were recruited at Nour-Nejat hospital, Tabriz, Iran (2012-2014). A hospital-based group of healthy controls was matched for age (n 231, aged 20-63 years old) and sex. Dietary data were collected using a valid 136-item FFQ. Principal component analysis generated two main components (Kaiser-Meyer-Olkin = 0·684), including a Healthy pattern (whole bread, fruits, vegetables, vegetable oils, legumes, spices, seafood, low-fat meat, skinless poultry, low-fat dairy products, nuts and seeds) and a Western pattern (starchy foods, high-fat meat and poultry, high-fat dairy products, hydrogenated fat, fast food, salt and sweets). High adherence to the Western pattern increased the risk of BBD (ORadj 5·59; 95 % CI 2·06, 15·10; P < 0·01), whereas high intake of the Healthy pattern was associated with a 74 % lower risk of BBD (95 % CI 0·08, 0·81; P < 0·05). In the BBD population, the Western pattern was correlated with over-expression of HIF-1α (radj 0·309, P < 0·05). There were inverse correlations between the Healthy pattern and expressions of PPAR-γ (radj -0·338, P < 0·05), HIF-1α (radj -0·340, P < 0·05) and VEGF-A (radj -0·286, P < 0·05). In conclusion, new findings suggested that the Healthy pattern was associated inversely with the risk of BBD, and this could be correlated with down-regulation of PPAR-γ, VEGF-A and HIF-1α genes, which might hold promise to preclude BBD of malignant pathological transformation.


Assuntos
Doenças Mamárias/genética , Dieta/efeitos adversos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , PPAR gama/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Estudos de Casos e Controles , Dieta/métodos , Inquéritos sobre Dietas , Dieta Saudável/estatística & dados numéricos , Feminino , Humanos , Irã (Geográfico) , Pessoa de Meia-Idade , Fenômenos Fisiológicos da Nutrição/genética , Análise de Componente Principal , Adulto Jovem
5.
Phys Chem Chem Phys ; 21(43): 23996-24006, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31646317

RESUMO

Since the discovery of surface-enhanced resonance Raman scattering (SERS), elucidating the charge-transfer (CT) mechanism has been a challenging and controversial process. Different theoretical models have been proposed to explain the effect of applied electrode potential on SERS-CT, but achieving a high-quality conserved trend of experimental observations and explaining the nature of the selective enhancement of the signals is not a trivial task and the results and conclusions are still in dispute. We investigated recently the performance of time-dependent excited-state gradient approximation under the effects of a uniform finite electric field in a simulation of the experimental spectra of pyridine on an Ag electrode. The singular patterns of the experimental spectra for symmetric and non-symmetric benzene-like derivative compounds and the consistent trends of enhancements of their signals under various electrode potentials motivated us to extend our simulation studies to 4-methylpyridine, pyrazine and pyrimidine molecules on silver metal clusters. For these molecules, selective enhancement and de-enhancement of totally symmetric (υ6a, υ9a and υ8a) and non-totally symmetric (υ6b and υ8b) modes upon changing the field were obtained and matched well with experimental observations. The selective enhancement of each signal in a zero field was explained by means of excited-state vector gradients and excited-state charge density difference for the S0→ SCT transition. On-field calculations showed slight perturbations of the geometries and electronic structures of the molecules. These on-field calculations also directly affected the magnitude of specific excited-state vector gradients and dimensionless displacements, and moreover the patterns of the spectra. The results of this investigation provided insight into the nature of the selective enhancements of signals and may help researchers propose the selection rules of SERS-CT.

6.
Dalton Trans ; 52(22): 7564-7580, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37191162

RESUMO

In this work, the three-component heterostructure of CeO2/CuO/NiO was synthesized by a co-precipitation procedure and heating at a temperature of 750 °C. Then, CeO2/CuO/NiO nanoparticles were successfully supported on N-doped reduced graphene oxide (N-rGO) by a hydrothermal method. The obtained nanomaterials were used as effective electrocatalysts for the oxygen evolution reaction and glucose sensing in an alkaline medium. The results indicated that when CeO2/CuO/NiO is anchored on N-rGO nanosheets, active catalytic sites increase. On the other hand, N-doped rGO enhances electrical conductivity and electron transfer for water or glucose oxidation. CeO2/CuO/NiO@N-rGO has a large electrochemically active surface area and more active catalytic positions, and thus exhibits high activity for the OER with a low overpotential of 290 mV, a suitable Tafel slope of 110 mV dec-1, and superior stability and durability for at least 10 hours. CeO2/CuO/NiO@N-rGO can also detect glucose with a high sensitivity of 912.7 µA mM-1 cm-2, a low detection limit of 0.053 µM, a wide linear range between 0.001 and 24 mM, and a short response time of about 2.9 s. Moreover, the high selectivity and stability of this electrode for glucose sensing show its potential for clinical applications.

7.
Pharmaceutics ; 14(7)2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35890398

RESUMO

Opening the blood brain barrier (BBB) under imaging guidance may be useful for the treatment of many brain disorders. Rapidly applied magnetic fields have the potential to generate electric fields in brain tissue that, if properly timed, may enable safe and effective BBB opening. By tuning magnetic pulses generated by a novel electropermanent magnet (EPM) array, we demonstrate the opening of tight junctions in a BBB model culture in vitro, and show that induced monophasic electrical pulses are more effective than biphasic ones. We confirmed, with in vivo contrast-enhanced MRI, that the BBB can be opened with monophasic pulses. As electropermanent magnets have demonstrated efficacy at tuning B0 fields for magnetic resonance imaging studies, our results suggest the possibility of implementing an EPM-based hybrid theragnostic device that could both image the brain and enhance drug transport across the BBB in a single sitting.

8.
IEEE Open J Eng Med Biol ; 1: 265-267, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33748768

RESUMO

GOAL: To develop a micron-scale device that can operate as an MRI-based reporter for the presence of SARS-CoV-2 virus. METHODS: Iron rod microdevices were constructed via template-guided synthesis and suspended in phosphate buffered saline (PBS). Heat-inactivated SARS-CoV-2 viruses were added to the samples and imaged with low-field MRI. RESULTS: MRI of microdevices and viruses showed decreased signal intensity at low concentrations of viruses that recovered at higher concentrations. Electron micrographs suggest that reduced MRI intensity may be due to concentration-dependent shielding of water protons from local magnetic inhomogeneities caused by the iron microdevices. CONCLUSIONS: The preliminary results presented in this letter provide justification for further studies exploring the potential diagnostic role of magnetic microdevices in assessing the presence and concentration of SARS-CoV-2 viruses.

9.
J Magn Reson ; 303: 82-90, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31026669

RESUMO

In this work, a dynamically tunable B0 field is used to perform variable-field NMR. The system consists of an array of electropermanent AlNiCo-5 magnets whose magnetizations are individually programmed using pulse-power control. This design allows the field strength to be varied for field-dispersion measurements. An ultra-broadband front-end is utilized that maintains efficient power transmission over a broad range of frequencies for robust operation without probe tuning. We perform T1-T2 correlation measurements at various B0 field strengths (0.5-2 MHz) and demonstrate discrimination of different dairy products. We observe variation in the frequency dependence of the proton spin-lattice relaxation for the different products as a function of the degree of protein hydration. This variable-field technique provides a low-cost alternative to fast field-cycling NMR and could open possibilities for novel contrast measurements and spatial encoding in magnetic resonance imaging.

10.
Micromachines (Basel) ; 10(4)2019 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-30935105

RESUMO

Soft, untethered microrobots composed of biocompatible materials for completing micromanipulation and drug delivery tasks in lab-on-a-chip and medical scenarios are currently being developed. Alginate holds significant potential in medical microrobotics due to its biocompatibility, biodegradability, and drug encapsulation capabilities. Here, we describe the synthesis of MANiACs-Magnetically Aligned Nanorods in Alginate Capsules-for use as untethered microrobotic surface tumblers, demonstrating magnetically guided lateral tumbling via rotating magnetic fields. MANiAC translation is demonstrated on tissue surfaces as well as inclined slopes. These alginate microrobots are capable of manipulating objects over millimeter-scale distances. Finally, we demonstrate payload release capabilities of MANiACs during translational tumbling motion.

11.
J Tradit Complement Med ; 7(3): 332-338, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28725629

RESUMO

AIM: The purpose of this study was to evaluate the effect of 50 and 100 mg doses of green cumin essential oil on glycemic and inflammatory indices in patients with diabetes type II. METHOD: In this randomized double-blind placebo-controlled clinical trial, subjects were divided into three groups after selecting them randomly according to the inclusion criteria: 1 - Cuminum cyminum capsule (100 mg/day,n = 33), 2 - C. cyminum capsule (50 mg/day, n = 33), and 3 - placebo (n = 33). Before and after 8 weeks of intervention, a blood sample was taken. FINDINGS: The findings demonstrated that the mean of the FBS, glycosylated hemoglobin (HgA1c) and the serum levels of insulin were significantly decreased and insulin sensitivity (HOMA-IR) was significantly increased in the groups receiving the 100 mg supplement (P < 0.001) and 50 mg supplement, but these indices were increased in the placebo group. The mean serum levels of TNF-α and hsCRP were significantly decreased, and serum levels of adiponectin was significantly increased at the end of the study in the groups receiving 100 mg (P < 0.001) and 50 mg (P = 0.008) supplement as well as in the group who received the placebo. There were no significant change in HOMA-B and QUICKI as insulin resistance parameters. DISCUSSION AND CONCLUSION: Administering C. cyminum supplement in patients with diabetes type II may decrease the serum levels of insulin, FBS, and glycosylated hemoglobin and also the inflammatory indices of TNF-α and hsCRP and increased the serum levels of adiponectin. In addition it may control the complications of diabetes type II in these patients.

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