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Colorectal cancer is among the well-known forms of cancer and a prominent cause of cancer demises worldwide. In vitro experiments reinforced by animal studies, as well as epidemiological studies of human colorectal cancer propose that the growth of this disease can be moderated by eating aspects. Dietary intake including green vegetables and fruits may result in the reduction of colon cancer chances. The finding suggests that the combinations of dietary nutrients may deliver additive or synergistic effects and might be a powerful method to avoid or eradicate colon cancer beginning and/or development. Flavonols are one of the most widespread dietary nutrients of the polyphenols-flavonoids and major constituent of Allium and Brassicaceae vegetables. Flavonols present in vegetables of Allium and Brassicaceae family are kaempferol, myricetin, quercetin, and isorhamnetin. These flavonols are claimed to have antiproliferative activity in vivo and in vitro against colorectal cancer. The objective of this review is to summarize the role of flavonols obtained from dietary sources in the prevention and treatment of colorectal cancer.
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The manufacturing and characterization of freeform optical surfaces are influenced by their high sensitivity to misalignments. In this work, the computational sampling moiré technique combined with phase extraction is developed for the precise alignment of freeform optics during fabrication and in metrology applications. This novel, to the best of our knowledge, technique achieves near-interferometry-level precision in a simple and compact configuration. This robust technology can be applied to industrial manufacturing platforms (such as diamond turning machines, lithography, and other micro-nano-machining techniques) as well as their metrology equipment. In a demonstration of computational data processing and precision alignment using this method, iterative manufacturing of freeform optical surfaces with a final-form accuracy of about 180â nm was accomplished.
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Indirect-imaging methods involve at least two steps, namely optical recording and computational reconstruction. The optical-recording process uses an optical modulator that transforms the light from the object into a typical intensity distribution. This distribution is numerically processed to reconstruct the object's image corresponding to different spatial and spectral dimensions. There have been numerous optical-modulation functions and reconstruction methods developed in the past few years for different applications. In most cases, a compatible pair of the optical-modulation function and reconstruction method gives optimal performance. A new reconstruction method, termed nonlinear reconstruction (NLR), was developed in 2017 to reconstruct the object image in the case of optical-scattering modulators. Over the years, it has been revealed that the NLR can reconstruct an object's image modulated by an axicons, bifocal lenses and even exotic spiral diffractive elements, which generate deterministic optical fields. Apparently, NLR seems to be a universal reconstruction method for indirect imaging. In this review, the performance of NLR isinvestigated for many deterministic and stochastic optical fields. Simulation and experimental results for different cases are presented and discussed.
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In recent years, there has been a significant transformation in the field of incoherent imaging with new possibilities of compressing three-dimensional (3D) information into a two-dimensional intensity distribution without two-beam interference (TBI). Most incoherent 3D imagers without TBI are based on scattering by a random phase mask exhibiting sharp autocorrelation and low cross-correlation along the depth axis. Consequently, during reconstruction, high lateral and axial resolutions are obtained. Scattering based-Imaging requires a wasteful photon budget and is therefore precluded in many power-sensitive applications. This study develops a proof-of-concept 3D incoherent imaging method using a rotating point spread function termed 3D Incoherent Imaging with Spiral Beams (3DI2SB). The rotation speed of the point spread function (PSF) with displacement and the orbital angular momentum has been theoretically analyzed. The imaging characteristics of 3DI2SB were compared with a direct imaging system using a diffractive lens, and the proposed system exhibited a higher focal depth than the direct imaging system. Different computational reconstruction methods such as the Lucy-Richardson algorithm (LRA), non-linear reconstruction (NLR), and the Lucy-Richardson-Rosen algorithm (LRRA) were compared. While LRRA performed better than both LRA and NLR for an ideal case, NLR performed better than both under real experimental conditions. Both single plane imaging, as well as synthetic 3D imaging, were demonstrated. We believe that the proposed approach might cause a paradigm shift in the current state-of-the-art incoherent imaging, fluorescence microscopy, and astronomical imaging.
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Interferenceless coded aperture correlation holography (I-COACH) is an incoherent digital holographic technique with lateral and axial resolution similar to a regular lens-based imaging system. The properties of I-COACH are dictated by the shape of the system's point response termed point spread hologram (PSH). As previously shown, chaotic PSHs which are continuous over some area on the image sensor enable the system to perform three-dimensional (3D) holographic imaging. We also showed that a PSH of an ensemble of sparse dots improves the system's signal-to-noise ratio (SNR) but reduces the dimensionality of the imaging from three to two dimensions. In this study, we test the midway shape of PSH, an ensemble of sparse islands distributed over the sensor plane. A PSH of isolated chaotic islands improves the SNR of the system compared to continuous chaotic PSH without losing the capability to perform 3D imaging. Reconstructed images of this new system are compared with images of continuous PSH, dot-based PSH, and direct images of a lens-based system. Visibility, SNR, and the product of visibility with SNR are the parameters used in the study. We also demonstrate the imaging capability of a system with partial annular apertures. The reconstruction results have better SNR and visibility than lens-based imaging systems with the same annular apertures.
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Shack-Hartmann wavefront sensors (SHWS) are generally used to measure the wavefront shape of light beams. Measurement accuracy and the sensitivity of these sensors are important factors for better wavefront sensing. In this paper, we demonstrate a new type of SHWS with better measurement accuracy than the regular SHWS. The lenslet array in the regular SHWS is replaced with an array of coded phase masks, and the principle of coded aperture correlation holography (COACH) is used for wavefront reconstruction. Sharper correlation peaks achieved by COACH improve the accuracy of the estimated local slopes of the measured wavefront and consequently improve the reconstruction accuracy of the overall wavefront. Experimental results confirm that the proposed method provides a lower mean square wavefront error by one order of magnitude in comparison to the regular SHWS.
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Partial aperture imaging is a combination of two different techniques; coded aperture imaging and imaging through an aperture that is only a part of the complete disk, commonly used as the aperture of most imaging systems. In the present study, the partial aperture is a ring where the imaging through this aperture resolves small details of the observed scene similarly to the full disk aperture with the same diameter. However, unlike the full aperture, the annular aperture enables using the inner area of the ring for other applications. In this study, we consider the implementation of this special aperture in medical imaging instruments, such as endoscopes, for imaging internal cavities in general and of the human body in particular. By using this annular aperture, it is possible to transfer through the internal open circle of the ring other elements such as surgical tools, fibers and illumination devices. In the proposed configuration, light originated from a source point passes through an annular coded aperture and creates a sparse, randomly distributed, intensity dot pattern on the camera plane. A combination of the dot patterns, each one recorded only once, is used as the point spread hologram of the imaging system. The image is reconstructed digitally by cross correlation between the object intensity response and the point spread hologram.
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The study evaluated the effect of commercial preparation of deltamethrin, Butox®, and fluoride (F-) co-exposure on the brain antioxidant status and cholinesterase activity in rats. Group A was untreated. Group B was gavaged Butox®, providing deltamethrin at the dose rate of 1.28 mg per kg body weight per day. Group C was administered F-, as NaF, in drinking water providing 20 ppm F-. Group D received both deltamethrin and F- at the same dosages as groups B and C, respectively. Although, glutathione S-transferase activity was induced only in Butox® alone treated group, the activities of superoxide dismutase and catalase were inhibited in all treatment groups when compared to the control group. Elevated lipid peroxidation was observed in the groups exposed to F-. The activity of erythrocyte acetylcholinesterase (AChE) was inhibited in Butox® treated groups, whereas brain AChE activity was inhibited in all treatment groups. In conclusion, both deltamethrin (given as Butox®) and F- inhibit AChE activity and produce oxidative stress in brain with F- producing more oxidative damage. However, compared to the individual exposures, the co-exposure of these chemicals does not produce any exacerbated alteration in these biochemical parameters.
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Antioxidantes/metabolismo , Encéfalo/efeitos dos fármacos , Inibidores da Colinesterase/toxicidade , Inseticidas/toxicidade , Nitrilas/toxicidade , Piretrinas/toxicidade , Fluoreto de Sódio/toxicidade , Acetilcolinesterase/sangue , Acetilcolinesterase/metabolismo , Animais , Biomarcadores/metabolismo , Encéfalo/enzimologia , Catalase/metabolismo , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Feminino , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/sangue , Proteínas Ligadas por GPI/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Medição de Risco , Superóxido Dismutase/metabolismoRESUMO
The current study investigated the effects of deltamethrin, fluoride (F(-)) and their combination on the hepatic oxidative stress and consequent alterations in blood biochemical markers of hepatic damage in rats. Significant hepatic oxidative stress and hepatic damage were observed in the toxicant exposed groups. These changes were higher in the deltamethrin-F(-) co-exposure treatment group, depicting a positive interaction between the two chemicals.
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Poluentes Ambientais/toxicidade , Fluoretos/toxicidade , Inseticidas/toxicidade , Fígado/efeitos dos fármacos , Nitrilas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Piretrinas/toxicidade , Animais , Enzimas/sangue , Feminino , Fígado/enzimologia , Fígado/patologia , Masculino , Distribuição Aleatória , Ratos , Ratos WistarRESUMO
Prevention of cross contamination with active pharmaceutical ingredients is crucial and requires special attention in pharmaceutical industries. Current method validation describes the determination of Nabumetone (NAB) residue on a stainless steel surface using swab sampling with a sensitive HPLC-DAD analysis. The acceptance limit was decided as 2 µg swab per 100 cm2. Cotton swabs impregnated with extraction solution were used to determine residual drug content. Recoveries were 90.88%, 91.42%, and 92. 21% with RSD ranging from 2.2% to 3.88% at three concentration levels. Residual concentration was found to be linear in the range of 0.1-4.56 µg/mL, when estimated using a Phenomenex Luna C18 (25 cm×5 µm×4.6 mm i.d.) column at 1.0 mL/min flow rate and 230 nm. The mobile phase consisted of a mixture of methanol:acetonitrile:water (55:30:15, v/v/v). The LOD and LOQ for NAB were found to be 0.05 and 0.16 µg/mL, respectively. The validated method was found to be simple, selective and sensitive for demonstration of cleaning validation of NAB residues on a stainless steel surface.
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Allium sativum L (garlic) is an essential component of many polyherbal oils used in traditional systems of medicine. Allyl disulfide has been a major component found in vegetable oil macerate of garlic, and can be used as reliable marker for determination of garlic in oil macerates of garlic. The HPLC separation of allyl disulfide was achieved on a Phenomenex Luna C18 (25 cm x 4.6 mm id x 5 pm particle size) column using acetonitrile-water-tetrahydrofuran (70 + 27 + 3, v/v/v) mobile phase at a flow rate of 1.0 mL/min. Quantitation was achieved with UV detection at 298 nm over the concentration range 8-48 microg/mL. HPTLC separation of allyl disulfide was achieved on an aluminum-backed layer of silica gel 60 F254 using n-hexane mobile phase. Quantitation was achieved by densitometric analysis at 298 nm over the 200-1200 ng/band concentration range. The methods were validated according to International Conference on Harmonization guidelines.
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Dissulfetos/análise , Óleos de Plantas/análise , Compostos Alílicos , Calibragem , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Indicadores e Reagentes , Limite de Detecção , Plantas Medicinais/química , Padrões de Referência , Reprodutibilidade dos Testes , Espectrofotometria UltravioletaRESUMO
A sensitive, simple, rapid, and efficient HPTLC method was developed and validated for the analysis of catechin in marketed Ayurvedic oil formulations containing Acacia catechu. Chromatography of methanolic-0.1% formic acid (7:3, v/v) extracts of these formulations was performed on silica gel 60 F254 aluminum-backed TLC plates of 0.2 mm layer thickness. The plate was developed up to 85 mm with the ternary-mobile phase chloroform-acetone-0.1% formic acid (7.7 + 1.5 + 0.8%, v/v/v) at 22 +/- 2 degrees C with 20 min of chamber saturation. The system produced compact spots of catechin at an Rf value of 0.36. The marker, catechin, was quantified at its maximum absorbance of 296 nm. The limit of detection and quantitation values were 6 and 20 ng/spot, respectively. The linear regression analysis data for the calibration plot showed a good linear relationship with a correlation coefficient of 0.9993 in the concentration range of 200-1200 ng/spot for catechin with respect to peak area. Repeatability of the method was 0.88% RSD. Recovery values from 97 to 102% indicate excellent accuracy of the method. The developed HPTLC method is accurate, precise, and cost-effective, and it can be successfully applied for the determination of catechin in marketed Ayurvedic oil formulations containing Acacia catechu.
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Acacia/química , Catequina/análise , Óleos de Plantas/análise , Calibragem , Química Farmacêutica , Cromatografia em Camada Fina , Indicadores e Reagentes , Ayurveda , Preparações de Plantas/análise , Padrões de Referência , Reprodutibilidade dos TestesRESUMO
Many polyherbal oil formulations in Indian and Chinese traditional systems of medicine used for control of skin diseases contain seeds of Psoralea corylifolia and roots of Plumbago zeylanica L. Psoralen and plumbagin are the reliable markers for Ps. corylifolia and Pl. zeylanica, respectively. However, no attempt is made to standardize the polyherbal oil formulations containing Ps. corylifolia and Pl. zeylanica in terms of their active ingredients or marker compounds. In this paper, a simple, rapid, and sensitive HPTLC method is described for the first time to identify and quantify psoralen and plumbagin from such polyherbal oil formulations. The methanolic extract of oil formulations was used for analysis of markers. Psoralen gives a sharp UV absorbance peak at 302 nm and plumbagin at 275 nm. Good resolution of psoralen (Rf = 0.37) and plumbagin (Rf = 0.77) was attained using toluene-ethyl acetate (7.5 + 2.5, v/v) mobile phase. The method was validated in terms of calibration curve, limits of detection and quantification, precision, accuracy, and robustness following a standard protocol. Polyherbal oil formulations were analyzed with reasonable accuracy, and no matrix interference was observed. The method developed can be used for marker-based quality assurance of oil formulations containing Ps. corylifolia and Pl. zeylanica as one active ingredient.
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Cromatografia em Camada Fina/métodos , Densitometria/métodos , Ficusina/análise , Naftoquinonas/análise , Plumbaginaceae/química , Psoralea/química , Química FarmacêuticaRESUMO
Many polyherbal oil formulations in traditional systems of medicine contain aconite root. This paper reports the development and validation of a simple, rapid, and sensitive HPTLC method for identification and quantification of aconitine from polyherbal oil formulations. Chromatography of methanolic extract of these formulations was performed on silica gel 60F254 aluminum-backed HPTLC plates with a 0.2 mm layer thickness. The plates were developed up to 85 mm with the binary mobile phase ethyl acetate-ethanol (7.5 + 2.5, v/v) at 22 +/- 2 degrees C with 20 min of chamber saturation. The system produced a compact band of the marker aconitine at an R(f) value of 0.33 that was quantified at its maximum absorbance of 238 nm. The LOD and LOQ values were found to be 20 and 70 ng/band, respectively. The linearity with respect to peak area was in the range of 300 to 1800 ng/band with an r of 0.9991. Polyherbal oil formulations were analyzed with reasonable accuracy, and no matrix interference was observed. The developed HPTLC method is accurate, precise, and cost-effective, and can be used for marker-based QA of polyherbal oil formulations containing Aconitum chasmanthum as one of the active ingredients.