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In the pursuit of magnesium (Mg) alloys with targeted mechanical properties, a multi-objective Bayesian optimisation workflow is presented to enable optimal Mg-alloy design. A probabilistic Gaussian process regressor model was trained through an active learning loop, while balancing the exploration and exploitation trade-off via an acquisition function of the upper confidence bound. New candidate alloys suggested by the optimiser within each iteration were appended to the training data, and the performance of this sequential strategy was validated via a regret analysis. Using the proposed approach, the dependency of the prediction error on the training data was overcome by considering both the predictions and their associated uncertainties. The method developed here, has been packaged into a web tool with a graphical user-interactive interface (GUI) that allows the proposed optimal Mg-alloy design strategy to be deployed.
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BACKGROUND AND PURPOSE: Flow diversion has gradually become a standard treatment for intracranial aneurysms of the anterior circulation. Recently, the off-label use of the flow diverters to treat posterior circulation aneurysms has also increased despite initial concerns of rupture and the suboptimal results. This study aimed to explore the change in complication rates and treatment outcomes across time for posterior circulation aneurysms treated using flow diversion and to further evaluate the mechanisms and variables that could potentially explain the change and outcomes. MATERIALS AND METHODS: A retrospective review using a standardized data set at multiple international academic institutions was performed to identify patients with ruptured and unruptured posterior circulation aneurysms treated with flow diversion during a decade spanning January 2011 to January 2020. This period was then categorized into 4 intervals. RESULTS: A total of 378 procedures were performed during the study period. Across time, there was an increasing tendency to treat more vertebral artery and fewer large vertebrobasilar aneurysms (P = .05). Moreover, interventionalists have been increasingly using fewer overlapping flow diverters per aneurysm (P = .07). There was a trend toward a decrease in the rate of thromboembolic complications from 15.8% in 2011-13 to 8.9% in 2018-19 (P = .34). CONCLUSIONS: This multicenter experience revealed a trend toward treating fewer basilar aneurysms, smaller aneurysms, and increased usage of a single flow diverter, leading to a decrease in the rate of thromboembolic and hemorrhagic complications.
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Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Humanos , Procedimentos Endovasculares/métodos , Curva de Aprendizado , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Resultado do Tratamento , Estudos de Coortes , Estudos Retrospectivos , Embolização Terapêutica/métodos , StentsRESUMO
AIMS: The primary standard treatment for classic Hodgkin's lymphoma (cHL) is chemotherapy and radiation therapy. However, some patients get relapsed, or their diseases become resistant. PD1 blocking antibodies have been used to increase the response of treatment in solid tumors, and led to potentially stable responses that are acceptable. Our purpose in this study is to investigate the effect of nivolumab as a PD1 blocking antibody on the survival rate of patients with Hodgkin's cancer. METHODS: Databases were found in International Medical Sciences, Web of Science, Medline, Scopus, Index Copernicus, PubMed, DOAJ, Google Scholar, EBSCO-CINAHL, and Persian databases containing SID and Magiran using keywords such as: "checkpoint inhibitor", "nivolumab", "Hodgkin lymphoma", and "PD1 Blockade". The risk of bias was determined by two external observers using the Cochrane checklists. After the search, the data provided in 51 documents was independently evaluated. Duplicate papers were excluded. Assessing the full texts of the remaining papers, 7 papers were approved. RESULTS: Pooled data of these seven studies revealed that the overall objective response rate was 68% (CI 64.1% to 72.1%; heterogeneity; I2 = 40.19%; p = 0.123) with partial remission (52%; CI 46.5% to 57.6%; heterogeneity; I2 = 28.36%; p = 0.212). In the pooled analysis, complete remission was 16.8 (CI 11.1% to 26.4%). Pooled data of six studies showed that stable disease was averaged to 19% (CI 16% to 23%; heterogeneity; I2 = 30%; p = 0.209; fixed-effect model). CONCLUSIONS: The results of the study indicate that nivolumab as a PD1 pathway inhibitor can be effective in treating relapsed and refractory cHL patients compared to other therapies, and lead to more effective treatment over the long term. Furthermore, the adverse effects of nivolumab are controllable and have a good safety profile.
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Antineoplásicos Imunológicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Doença de Hodgkin/mortalidade , Recidiva Local de Neoplasia/mortalidade , Nivolumabe/uso terapêutico , Terapia de Salvação , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/patologia , Humanos , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Estudos Prospectivos , Indução de Remissão , Taxa de SobrevidaRESUMO
AIM: The aim of this study is to find an optimum material to protect garment for protection against 99Tcm radionuclide. MATERIALS AND METHODS: Monte Carlo simulation code was applied to investigate radiation attenuation of 13 shielding materials including: Ba, gray Sn, white Sn, Sb, Bi, Bi2O3, BaSO4, Sn/W, Sb/W, Pb and W with thicknesses of 0.5 and 1 mm to determine an optimum protective garment material in nuclear medicine against 99Tcm. Furthermore, the dose enhancement on the staff body was investigated for shielding materials such as tungsten and lead. RESULTS: The findings of the simulations show that the maximum and minimum attenuation obtained with thicknesses of 1 mm W and 1 mm BaSO4 were 96.46% and 14.2%, respectively. The results also demonstrate that tungsten does not cause any dose enhancement on staff body but this is not true for lead. Tungsten provides the highest radiation attenuation without dose enhancement on the body of staff. CONCLUSION: Among materials evaluated, tungsten is the optimum material and it can be applied for the design of protective garment for nuclear medicine staff against 99Tcm.
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BACKGROUND: Radiation therapy using electron beams is a promising method due to its physical dose distribution. Monte Carlo (MC) code is the best and most accurate technique for forespeaking the distribution of dose in radiation treatment of patients. MATERIAL AND METHODS: We report an MC simulation of a linac head and depth dose on central axis, along with profile calculations. The purpose of the present research is to carefully analyze the application of MC methods for the calculation of dosimetric parameters for electron beams with energies of 8-14 MeV at a Siemens Primus linac. The principal components of the linac head were simulated using MCNPX code for different applicators. RESULTS: The consequences of measurements and simulations revealed a good agreement. Gamma index values were below 1 for most points, for all energy values and all applicators in percent depth dose and dose profile computations. A number of states exhibited rather large gamma indices; these points were located at the tail of the percent depth dose graph; these points were less used in in radiotherapy. In the dose profile graph, gamma indices of most parts were below 1. The discrepancies between the simulation results and measurements in terms of Zmax, R90, R80 and R50 were insignificant. The results of Monte Carlo simulations showed a good agreement with the measurements. CONCLUSION: The software can be used for simulating electron modes of a Siemens Primus linac when direct experimental measurements are not feasible.
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BACKGROUND: One of the main causes of induction of secondary cancer in radiation therapy is neutron contamination received by patients during treatment. Objective: In the present study the impact of wedge and block on neutron contamination production is investigated. The evaluations are conducted for a 15 MV Siemens Primus linear accelerator. METHODS: Simulations were performed using MCNPX Monte Carlo code. 30Ë, 45Ë and 60Ë wedges and a cerrobend block with dimensions of 1.5 × 1.5 × 7 cm3 were simulated. The investigation were performed in the 10 × 10 cm2 field size at source to surface distance of 100 cm for depth of 0.5, 2, 3 and 4 cm in a water phantom. Neutron dose was calculated using F4 tally with flux to dose conversion factors and F6 tally. RESULTS: Results showed that the presence of wedge increases the neutron contamination when the wedge factor was considered. In addition, 45Ë wedge produced the most amount of neutron contamination. If the block is in the center of the field, the cerrobend block caused less neutron contamination than the open field due to absorption of neutrons and photon attenuation. The results showed that neutron contamination is less in steeper depths. The results for two tallies showed practically equivalent results. CONCLUSION: Wedge causes neutron contamination hence should be considered in therapeutic protocols in which wedge is used. In terms of clinical aspects, the results of this study show that superficial tissues such as skin will tolerate more neutron contamination than the deep tissues.
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BACKGROUND: To enhance the dose to tumor, the use of high atomic number elements has been proposed. OBJECTIVE: The aim of this study is to investigate the effect of gold nanoparticle distribution on dose enhancement in tumor when the tumor is irradiated by typical monoenergetic X-ray beams by considering homogeneous and inhomogeneous distributions of gold nanoparticles (GNPs) in the tumor. METHODS: MCNP-4C Monte Carlo code was utilized for the simulation of a source, a phantom containing tumor and gold nanoparticles with concentrations of 10, 30 and 70 mg Au/g tumor. A 15 cm×15 cm×15 cm cubic water phantom was irradiated with a small planar source with four monoenergetic X-ray beams of 35, 55, 75 and 95 keV energy. Furthermore, tumor depths of 2.5 cm, 4.5 cm and 6.5 cm with homogeneous and inhomogeneous distributions of nanoparticles were studied. Each concentration, photon energy, tumor depth and type of distribution was evaluated in a separate simulation. RESULTS: Results have shown that dose enhancement factor (DEF) in tumor increases approximately linearly with the concentration of gold nanoparticles. While DEF has fluctuations with photon energy, 55 keV photons have the highest DEF values compared to other energies. While DEF has relatively the same values with tumor located at various depths, inhomogeneous distribution of GNP has shown different results compared with the homogeneous model. Dose enhancement can be expected with relatively deep seated tumors in radiotherapy with low energy X-rays. Inhomogeneous model is recommended for the purpose of dose enhancement study because it mimics the real distribution of GNPs in tumor.
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BACKGROUND: Radiotherapy can often lead to thyroid dysfunction. Some studies demonstrated that treatment of breast cancer by RT can expose thyroid gland to high doses of radiation. The aim of this systematic review is to evaluate consideration of thyroid gland as an organ at risk. METHODS: In this systematic review and meta-analysis to select initial studies, a comprehensive search by two independent reviewers was performed. Electronical databases following: Web of Science, Google Scholar, Scopus, PubMed, Elsevier, Embase, ProQuest and Persian databases such as Iranmedex, Magiran, and SID were searched. All searches were restricted to English language between 1985 and 2017. A random effect meta-analysis is applied to estimate pooled effect size across initial studies. Funnel plot with Egger's test is used to assess potential publication bias. RESULTS: Totally, five studies (478 samples) were included in meta-analysis. The meta-analyses of result showed that thyroid gland is affected by radiotherapy significantly and the TSH increased after radiotherapy (z = 2.68, P = 0.007). The pooled estimate of difference mean for TSH was 0.90 (95% CI 0.24, 1.55). In studies among patients with breast cancer RT, hypothyroidism was reported more than other thyroid disorders. There was not showed possibility publication bias among studies (P > 0.05). CONCLUSION: This study demonstrated that thyroid gland is affected by radiotherapy significantly and the TSH increased after radiotherapy. Protecting thyroid gland during radiation and follow-up of patients with breast cancer RT are suggested for the assessment of thyroid gland dysfunction.
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Neoplasias da Mama/radioterapia , Órgãos em Risco/efeitos da radiação , Radioterapia/efeitos adversos , Glândula Tireoide/efeitos da radiação , Relação Dose-Resposta à Radiação , Feminino , Humanos , Hipotireoidismo/etiologia , Hipotireoidismo/patologia , Hipotireoidismo/fisiopatologia , Órgãos em Risco/patologia , Órgãos em Risco/fisiopatologia , Glândula Tireoide/patologia , Glândula Tireoide/fisiopatologia , Tireotropina/metabolismoRESUMO
Iatrogenic and traumatic cerebral internal carotid artery injuries are uncommon but potentially lethal complications. Direct surgical repair of ICA injuries may be difficult in an acute setting. However, endovascular treatment with a flow-diverter embolization device is a feasible alternative technique that we experienced. In this clinical report, we describe demographic data, radiographic images, lesion characteristics, endovascular procedure notes, postprocedural hospital course, and follow-up digital subtraction angiography of 5 patients. At least 6-month follow-up was available in all patients without occurrence of rebleeding and other complications.
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Lesões das Artérias Carótidas/terapia , Embolização Terapêutica/instrumentação , Procedimentos Endovasculares/instrumentação , Adulto , Lesões das Artérias Carótidas/etiologia , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Feminino , Humanos , Doença Iatrogênica , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Stents/efeitos adversosRESUMO
Chronic low-grade inflammation has been suggested as a key contributor of the pathogenesis and development of polycystic ovary syndrome (PCOS). To investigate the association between oxidative stress status and inflammatory cytokines in follicular fluid of 21 PCOS women compared to 21 women with normal ovarian function who underwent intra-cytoplasmic sperm injection. Concentration of IL-6, IL-8, IL-10, and TNF-α was measured using sandwich ELISA. Oxidative stress was examined by measuring total oxidant status (TOS), malondialdehyde (MDA), total antioxidant capacity (TAC), and thiol groups. PCOS women had an elevated concentration of MDA and TOS compared to controls. Levels of TAC and thiol groups were lower in PCOS compared to controls. PCOS patients had a higher concentration of IL-6, IL-8, and TNF-α compared to controls. Concentration of IL-10 was lower in PCOS compared to controls. Significant correlations were found between MDA and TOS concentration with TNF-α and between IL-6 and MDA, IL-8 and TAC, IL-10 and TOS levels and also between IL-10 and TAC levels. TAC and thiol groups were negatively correlated with TNF-α. Increased oxidative stress in PCOS is associated with inflammation which is closely linked. Inflammation can induce production of inflammatory cytokines in this syndrome and directly stimulates excess ovarian androgen production.
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Interleucina-6/metabolismo , Interleucina-8/metabolismo , Ovário/imunologia , Estresse Oxidativo , Síndrome do Ovário Policístico/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima , Adulto , Biomarcadores/metabolismo , Estudos Transversais , Regulação para Baixo , Feminino , Líquido Folicular/imunologia , Líquido Folicular/metabolismo , Hospitais Universitários , Humanos , Infertilidade Feminina/etiologia , Infertilidade Feminina/terapia , Interleucina-10/metabolismo , Irã (Geográfico) , Pessoa de Meia-Idade , Ovário/metabolismo , Ovário/fisiopatologia , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/fisiopatologia , Injeções de Esperma IntracitoplásmicasRESUMO
Promising experimental studies suggest that quercetin has potential anti-inflammatory effects. However, the results of current clinical trials on quercetin's effects on the C-reactive protein (CRP), a sensitive inflammatory biomarker, are ambiguous. We conducted a meta-analysis of available randomized controlled trials (RCTs) to resolve this inconsistency and quantify the net effect of quercetin on circulating CRP concentrations. A systematic search was performed in several databases including SCOPUS, PubMed-Medline and Google Scholar until 16 June 2016. We used a random-effects model in combination with weight mean difference (WMD) and 95% confidence intervals (CI) for data analysis. Standard methods were used for the assessment of heterogeneity, meta-regression, sensitivity analysis and publication bias. The meta-analysis of seven RCTs (10 treatment arms) showed a significant reduction of circulating CRP levels (WMD: -0.33 mg/l; 95% CI: -0.50 to -0.15; P<0.001) following quercetin supplementation. In the subgroup analysis, a significant reducing effect was observed in trials with ⩾500 mg/day dosage (WMD: -0.34 mg/l; 95% CI: -0.52, -0.16; P⩽0.001) and in those with CRP <3 mg/l (WMD: -0.34 mg/l; 95% CI: -0.51, -0.18; P⩽0.001). In meta-regression, there was no association between changes in CRP concentrations, dose of supplementation and CRP baseline values. Our findings showed a significant effect of quercetin supplementation on the C-reactive protein-especially at doses above 500 mg/day and in patients with CRP <3 mg/l.
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Antioxidantes/farmacologia , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Quercetina/farmacologia , Suplementos Nutricionais , Humanos , Terapia Nutricional , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
OBJECTIVE: The aim of the present study is to simulate 6 MV and 18 MV photon beam energies of a Siemens Primus Plus medical linear accelerator (Linac) and to verify the simulation by comparing the results with the measured data. METHODS: The main components of the head of Siemens Primus Plus linac were simulated using MCNPX Monte Carlo (MC) code. To verify the results, experimental data of percentage depth dose (PDD) and beam dose profile for 5 × 5 cm2, 10 × 10 cm2 and 20 × 20 cm2 field sizes were measured and compared with simulation results. Moreover, gamma function was used to compare the measurement and simulation data. RESULTS: The results show a good agreement, within 1%, was observed between the data calculated by the simulations and those obtained by measurement for 6 MV photon beam, while it was within 2% for 18 MV photon beam, except in the build-up region for both beams. Gamma index values were less than unity in most data points for all the mentioned energies and fields. To calculate the dose in the phantom, cells were selected in different modes, one of the modes due to the lack of dose gradient and overlapping, produced better results than others produce. CONCLUSION: There was good settlement between measured and MC simulation values in this research. The simulation programs can be used for photon modes of Siemens Primus Plus linac in conditions in which it is not possible to perform experimental measurements.
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OBJECTIVE: Radiochromic EBT3 film is a later generation of radiochromic films. The aim of this study is to compare EBT and EBT3 radiochromic films in radiotherapy fields of breast cancer. METHODS: A RANDO phantom was irradiated by a 6 MV Siemens Primus linac with medial and lateral fields of radiotherapy of breast cancer. Dosimetry was performed in various points in the fields using EBT and EBT3 films. Films were scanned by a Microtek color scanner. Dose values from two films in corresponding points were compared. RESULTS: In the investigation of calibration, net optical density (NOD) of EBT radiochromic is more than the EBT3 radiochromic film. The highest percentage difference between NODs of two films is related to 0.75 Gy and equals to 14.19%. The lowest value is related to 0.2 Gy dose and is equal to 3.31%. The highest percentage difference between two films on the RANDO phantom in breast cancer fields is 13.51% and the minimum value is equal to 0.33%. CONCLUSION: From the comparison between the two films, most of the points show differences in dose in the measurements in fields of breast cancer radiotherapy. These differences are attributed to the thickness of the active layers, the overall thickness of the films, and the difference in the calibration fitted functions. The advantage of EBT film over EBT3 is a higher sensitivity; on the other hand EBT3 film allows to use its both sides in the scanning process and it is a new version of this film type.
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BACKGROUND: EBT and EBT3 radioChromic films have been used in radiotherapy dosimetry for years. OBJECTIVE: The aim of the current study is to compare EBT and EBT3 radioChromic films in dosimetry of radiotherapy fields for treatment of parotid cancer. METHODS: Calibrations of EBT and EBT3 films were performed with identical setups using a 6 MV photon beam of a Siemens Primus linac. Skin dose was measured at different points in the right anterior oblique (RAO) and right posterior oblique (RPO) fields by EBT and EBT3 films on a RANDO phantom. RESULTS: While dosimetry was performed with the same conditions for the two film types for calibration and in phantom in parotid cancer radiotherapy, the measured net optical density (NOD) in EBT film was found to be higher than that from EBT3 film. The minimum difference between these two films under calibration conditions was about 2.9% (for 0.2 Gy) with a maximum difference of 35.5% (for 0.5 Gy). In the therapeutic fields of parotid cancer radiotherapy at different points, the measured dose from EBT film was higher than the EBT3 film. In these fields the minimum and maximum measured dose differences were 16.0% and 25.5%, respectively. CONCLUSION: EBT film demonstrates higher NOD than EBT3 film. This effect may be related to the higher sensitivity of EBT film over EBT3 film. However, the obtained dose differences between these two films in low dose range can be due to the differences in fitting functions applied following the calibration process.
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OBJECTIVE: The aim of this study is to evaluate the effect of tissue composition on dose distribution in electron beam radiotherapy. METHODS: A Siemens Primus linear accelerator and a phantom were simulated using MCNPX Monte Carlo code. In a homogeneous cylindrical phantom, six types of soft tissue and three types of tissue-equivalent materials were investigated. The tissues included muscle (skeletal), adipose tissue, blood (whole), breast tissue, soft tissue (9-components) and soft tissue (4-component). The tissue-equivalent materials were water, A-150 tissue-equivalent plastic and perspex. Electron dose relative to dose in 9-component soft tissue at various depths on the beam's central axis was determined for 8, 12, and 14 MeV electron energies. RESULTS: The results of relative electron dose in various materials relative to dose in 9-component soft tissue were reported for 8, 12 and 14 MeV electron beams as tabulated data. While differences were observed between dose distributions in various soft tissues and tissue-equivalent materials, which vary with the composition of material, electron energy and depth in phantom, they can be ignored due to the incorporated uncertainties in Monte Carlo calculations. CONCLUSION: Based on the calculations performed, differences in dose distributions in various soft tissues and tissue-equivalent materials are not significant. However, due to the difference in composition of various materials, further research in this field with lower uncertainties is recommended.
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A series of novel piperazine analogues bearing quinolin-8-yloxy-butan--ones/pyridin-2-yloxy-ethanones were synthesized by a simple and convenient approach based on various substituted piperazine incorporating quinoline and pyridine moieties. The analogues were evaluated for in vitro antioxidant activity against 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and ferrous ion radical scavenging activities and anti-inflammatory activity by inhibition of Vipera russelli venom (PLA2) and gastric K+/H(+)-ATPase activities. Most of the title compounds exhibited promising activity. Best antioxidant and PLA2-inhibiting activities were found for piperazine analogues with phenyl and nitro phenyl groups, whereas methoxy group on phenyl piperazine indicated selectivity for the H+/K(+)-ATPase.
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Anti-Inflamatórios/síntese química , Antioxidantes/síntese química , Inibidores Enzimáticos/síntese química , Piperazinas/síntese química , Piridinas/química , Quinolinas/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Compostos de Bifenilo/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Radicais Livres/química , Fosfolipases A2 do Grupo II/antagonistas & inibidores , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Estrutura Molecular , Células Parietais Gástricas/efeitos dos fármacos , Células Parietais Gástricas/enzimologia , Picratos/química , Piperazinas/química , Piperazinas/farmacologia , OvinosRESUMO
Gamma camera is an important apparatus in nuclear medicine imaging. Its detection part is consists of a scintillation detector with a heavy collimator. Substitution of semiconductor detectors instead of scintillator in these cameras has been effectively studied. In this study, it is aimed to introduce a new design of P-N semiconductor detector array for nuclear medicine imaging. A P-N semiconductor detector composed of N-SnO2 :F, and P-NiO:Li, has been introduced through simulating with MCNPX monte carlo codes. Its sensitivity with different factors such as thickness, dimension, and direction of emission photons were investigated. It is then used to configure a new design of an array in one-dimension and study its spatial resolution for nuclear medicine imaging. One-dimension array with 39 detectors was simulated to measure a predefined linear distribution of Tc(99_m) activity and its spatial resolution. The activity distribution was calculated from detector responses through mathematical linear optimization using LINPROG code on MATLAB software. Three different configurations of one-dimension detector array, horizontal, vertical one sided, and vertical double-sided were simulated. In all of these configurations, the energy windows of the photopeak were ± 1%. The results show that the detector response increases with an increase of dimension and thickness of the detector with the highest sensitivity for emission photons 15-30° above the surface. Horizontal configuration array of detectors is not suitable for imaging of line activity sources. The measured activity distribution with vertical configuration array, double-side detectors, has no similarity with emission sources and hence is not suitable for imaging purposes. Measured activity distribution using vertical configuration array, single side detectors has a good similarity with sources. Therefore, it could be introduced as a suitable configuration for nuclear medicine imaging. It has been shown that using semiconductor P-N detectors such as P-NiO:Li, N-SnO2 :F for gamma detection could be possibly applicable for design of a one dimension array configuration with suitable spatial resolution of 2.7 mm for nuclear medicine imaging.
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In this work, anthocyanin stability and color of encapsulated freeze-dried saffron petal's extract with various matrices consisting gum Arabic (AG) and maltodextrin (M7 and M20) were studied. Total anthocyanins of powders and color parameters (a*, b*, L*, C, H° and TCD) were measured immediately after production and during storage up to 10 weeks by pH differential method and computer vision, respectively. Different compounds of wall materials did not show any significant differences in terms of stabilizing anthocyanins (P<0.01) and no significant decrease in anthocyanin content of the powders was observed after storage. The efficiency order of wall materials considering total color differences (TCD) was AG>M20>M7. By evaluating 3D surface and Cox trace plots it was revealed that wall formulas which had the lowest amount of AG and highest amounts of M20 and M7 showed the lowest total color differences after storage (P<0.05). To conclude, microencapsulation by freeze drying could be recommended as a suitable method for stabilizing anthocyanins of saffron petal's extract.
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Antocianinas/química , Crocus , Flores/química , Goma Arábica/química , Pigmentos Biológicos/química , Polissacarídeos/química , Antocianinas/isolamento & purificação , Composição de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Estabilidade de Medicamentos , Pigmentos Biológicos/isolamento & purificaçãoRESUMO
Peptic ulcer disease is a common illness, affecting a considerable number of people worldwide, and its occurrence can be influenced by environmental and genetic factors. Heat shock proteins (HSPs) function mostly as molecular chaperones, and are induced by various stresses. The A to G transition at position 1267 of the HSPA1B gene was shown to correlate with changes in the level of HSPA mRNA expression. Here, the relation between A1267G polymorphism of the HSPAIB gene and risk of peptic ulcer in the Iranian population was evaluated. One hundred subjects, who underwent gastroscopy, took part in the study. DNA samples extracted from the biopsy tissues were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). After gastroscopy, peptic ulcer was diagnosed for 50 patients; among them the distribution of AA/AB/BB genotypes was 10, 88 and 2%, respectively. As for the other 50 subjects (without peptic ulcer) included in the control group, the AA/AB/BB genotypes were identified as 40, 52 and 8%, respectively. A significant association was found between the HSPA1B genotype and peptic ulcer (6.76 OR; 95% CI, 2.26-20.2; p = 0.0006). Thus, the HSPA1B A1267G polymorphism may be a marker of susceptibility to peptic ulcer.