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1.
BMC Med Genomics ; 14(1): 46, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568133

RESUMO

BACKGROUND: Graves' disease(GD) has a tendency for familial aggregation, but it is uncommon to occur in more than two generations. However, little is known about susceptibility genes for GD in the three-generation family. METHODS: DNA were extracted from three-generation familial GD patient with a strong genetic background in a Chinese Han population. The Whole Exome Sequencing (WES) was utilized to screen the genome for SNVs associated with GD and the Sanger Sequencing was used to confirm the potential disease-causing genes. RESULTS: In the case study, there were five patients with Graves' disease(GD) from a three-generation family. The SNVs of MAP7D2(c. 452C > T: p. A151V), SLC1A7(c. 1204C > T: p. R402C), TRAF3IP3(c. 209A > T: p. N70I), PTPRB(c. 3472A > G: p. S1158G), PIK3R3(c. 121C > T: p. P41S), DISC1(c. 1591G > C: p. G531R) were found to be associated with the familial GD and the Sanger sequencing had confirmed these variations. Furthermore, PolyPhen-2 score showed that the variants in TRAF3IP3, PTPRB, PIK3R3 are more likely to change protein functions. CONCLUSION: The MAP7D2, SLC1A7, TRAF3IP3, PTPRB, PIK3R3, DISC1 may be the candidate susceptibility genes for familial GD from a three generations family.

2.
FEBS Open Bio ; 2021 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-33455075

RESUMO

Multiple clinical trials have shown that monoclonal antibodies (mAbs) against programmed death-ligand 1 (PD-1/PD-L1) can benefit patients with lung cancer by increasing their progression-free survival and overall survival. However, a significant proportion of patients do not respond to anti-PD-1/PD-L1 mAbs. In the present study, we investigated whether galectin (Gal)-3 inhibitors can enhance the antitumor effect of PD-L1 blockade. Using the NSCLC-derived cell line A549, we examined the expression of Gal-3 in lung cancer cells under hypoxic conditions and investigated the regulatory effect of Gal-3 on PD-L1 expression, which is mediated by the STAT3 pathway. We also explored whether Gal-3 inhibition can facilitate the cytotoxic effect of T cells induced by PD-L1 blockade. The effects of combined use of a Gal-3 inhibitor and PD-L1 blockade on tumor growth and T-cell function were also investigated, and we found that hypoxia increased the expression and secretion of Gal-3 by lung cancer cells. Gal-3 increased PD-L1 expression via the upregulation of STAT3 phosphorylation, and administration of a Gal-3 inhibitor enhanced the effect of PD-L1 blockade on the cytotoxic activity of T cells against cancer cells in vitro. In a mouse xenograft model, the combination of a Gal-3 inhibitor and PD-L1 blockade synergistically suppressed tumor growth. Furthermore, the administration of a Gal-3 inhibitor enhanced T-cell infiltration and granzyme B release in tumors. Collectively, our results show that Gal-3 increases PD-L1 expression in lung cancer cells and that the administration of a Gal-3 inhibitor as an adjuvant enhanced the antitumor activity of PD-L1 blockade.

3.
Environ Res ; 193: 110560, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33279493

RESUMO

Titanium dioxide (TiO2) is widely used to purify air pollutants in environmental engineering, but it is only activated by ultraviolet (UV) light. The metal or nonmetal single doping of TiO2 cannot observably improve the purification efficiency of TiO2 under visible light. To further increase the photocatalytic activity and purification efficiency of TiO2 on vehicle exhaust under visible light, nitrogen (N)-vanadium (V) co-doped TiO2 was first prepared. The influences of N-V co-doping on phase structures, morphology, microstructures, electronic structures, and photo-absorption performances were then observed and examined using X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-visible light diffuse reflectance spectra. Purification efficiency and reaction rates of N-V co-doped TiO2 on NOx, HC, CO and CO2 in vehicle exhaust were studied using a purification test system under UV and visible light irradiations, respectively. Results indicate that N and V are synchronously doped into the crystal structures of TiO2 to replace O and Ti, respectively. N and V show the synergistic co-doping effect to suppress the grain growth of TiO2 and improve the dispersity and specific surface area of TiO2. Also, the N-V co-doping introduces more lattice distortions and defects in the crystal lattices of TiO2. Further, N presents in the form of Ti-O-N and O-Ti-N bonds, and V exists in the form of V5+ and V4+. These form the impurity energy level in the band gap to narrow the energy band of TiO2. Additionally, the N-V co-doping broadens the photoabsorption threshold of TiO2 from 387 nm to 611 nm. These results show that N-V co-doping increases the photocatalytic activity of TiO2. Finally, the N-V co-doped TiO2 shows higher catalytic purification efficiency on NOx and HC under UV and visible light. The N-V co-doping obviously increases the purification efficiency of TiO2 on CO and CO2 when exposed to visible light, and their reversible reactions are not found. The N-V co-doping of TiO2 is a feasible approach to purify vehicle exhaust under visible light irradiations.

4.
Materials (Basel) ; 13(24)2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339159

RESUMO

The electronics related to the fifth generation mobile communication technology (5G) are projected to possess significant market potential. High dielectric constant microwave ceramics used as filters and resonators in 5G have thus attracted great attention. The Ba6-3x(Sm1-yNdy)8+2xTi18O54 (x = 2/3) ceramic system has aroused people's interest due to its underlying excellent microwave dielectric properties. In this paper, the relationships between the dielectric constant, Nd-doped content, sintering temperature and the density of Ba6-3x(Sm1-yNdy)8+2xTi18O54 (x = 2/3) ceramics were studied. The linear regression equation was established by statistical product and service solution (SPSS) data analysis software, and the factors affecting the dielectric constant have been analyzed by using the enter and stepwise methods, respectively. It is found that the model established by the stepwise method is practically significant with Y = -71.168 + 6.946x1 + 25.799x3, where Y, x1 and x3 represent the dielectric constant, Nd content and the density, respectively. According to this model, the influence of density on the dielectric constant is greater than that of Nd doping concentration. We bring the linear regression analysis method into the research field of microwave dielectric ceramics, hoping to provide an instructive for the optimization of ceramic technology.

5.
J Ind Microbiol Biotechnol ; 47(12): 1083-1097, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33191463

RESUMO

D-Limonene, a cyclized monoterpene, possesses citrus-like olfactory property and multi-physiological functions, which can be used as a bioactive compound and flavor to improve the overall quality of alcoholic beverages. In our previous study, we established an orthogonal pathway of D-limonene synthesis by introducing neryl diphosphate synthase 1 (tNDPS1) and D-limonene synthase (tLS) in Saccharomyces cerevisiae. To further increase D-limonene formation, the metabolic flux of the mevalonate (MVA) pathway was enhanced by overexpressing the key genes tHMGR1, ERG12, IDI1, and IDI1WWW, respectively, or co-overexpressing. The results showed that strengthening the MVA pathway significantly improved D-limonene production, while the best strain yielded 62.31 mg/L D-limonene by co-expressing tHMGR1, ERG12, and IDI1WWW genes in alcoholic beverages. Furthermore, we also studied the effect of enhancing the MVA pathway on the growth and fermentation of engineered yeasts during alcoholic beverage fermentation. Besides, to further resolve the problem of yeast growth inhibition, we separately investigated transporter proteins of the high-yielding D-limonene yeasts and the parental strain under the stress of different D-limonene concentration, suggesting that the transporters of Aus1p, Pdr18p, Pdr5p, Pdr3p, Pdr11p, Pdr15p, Tpo1p, and Ste6p might play a more critical role in alleviating cytotoxicity and improving the tolerance to D-limonene. Finally, we verified the functions of three transporter proteins, finding that the transporter of Aus1p failed to transport D-limonene, and the others (Pdr5p and Pdr15p) could improve the tolerance of yeast to D-limonene. This study provided a valuable platform for other monoterpenes' biosynthesis in yeast during alcoholic beverage fermentation.

6.
Materials (Basel) ; 13(18)2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32927682

RESUMO

To reduce the thermal-oxidative aging of asphalt and the release amount of harmful volatiles during the construction of asphalt pavement, a new composite anti-aging agent was developed. Since the volatiles were mainly released from saturates and aromatics during the thermal-oxidative aging of asphalt, expanded graphite (EG) was selected as a stabilizing agent to load magnesium hydroxide (MH) and calcium carbonate (CaCO3) nanoparticles for preparing the anti-aging agents of saturates and aromatics, respectively. Thermal stability and volatile constituents released from saturates and aromatics before and after the thermal-oxidative aging were characterized using the isothermal Thermogravimetry/Differential Scanning Calorimetry-Fourier Transform Infrared Spectrometer test (TG/DSC-FTIR test). Test results indicate that anti-aging agents of EG/MH and EG/CaCO3 effectively inhibit the volatilization of light components in asphalt and improve the thermal stability of saturates and aromatics. Then, the proportions of EG, MH, and CaCO3 added in the developed composite anti-aging agent of EG/MH/CaCO3 are 2:1:3 by weight. EG/MH/CaCO3 plays a synergetic effect on inhibiting the thermal-oxidative aging of asphalt, and reduces the release amount of harmful volatiles during the thermal-oxidative aging after EG/MH/CaCO3 is added into asphalt at the proposed content of 10 wt.%. EG plays a synergistic role with MH and CaCO3 nanoparticles to prevent the chain reactions, inhibiting the thermal-oxidative aging of asphalt.

7.
J Ind Microbiol Biotechnol ; 47(6-7): 511-523, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32495196

RESUMO

d-Limonene, a cyclic monoterpene, possesses citrus-like olfactory property and multi-physiological functions. In this study, the d-limonene synthase (tLS) from Citrus limon was codon-optimized and heterologously expressed in Saccharomyces cerevisiae. The metabolic flux of canonical pathway based on overexpressing endogenous geranyl diphosphate synthase gene (ERG20) and its variant ERG20F96W-N127W was strengthened for improvement d-limonene production in Chinese Baijiu. To further elevate production, we established an orthogonal pathway by introducing neryl diphosphate synthase 1 (tNDPS1) from Solanum lycopersicum. The results showed that expressing ERG20 and ERG20F96W-N127W could enhance d-limonene synthesis, while expressing heterologous NPP synthase gene significantly increase d-limonene formation. Furthermore, we constructed a tLS-tNDPS1 fusion protein, and the best strain yielded 9.8 mg/L d-limonene after optimizing the amino acid linker and fusion order, a 40% improvement over the free enzymes during Chinese Baijiu fermentation. Finally, under the optimized fermentation conditions, a maximum d-limonene content of 23.7 mg/L in strain AY12α-L9 was achieved, which was the highest reported production in Chinese Baijiu. In addition, we also investigated that the effect of d-limonene concentration on yeast growth and fermentation. This study provided a meaningful insight into the platform for other valuable monoterpenes biosynthesis in Chinese Baijiu fermentation.

8.
J Appl Clin Med Phys ; 21(6): 33-43, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32237271

RESUMO

PURPOSE: To investigate planning time and number of optimizations in routine clinical lung cancer plans based on the plan quality improvements following each optimization. MATERIALS AND METHOD: We selected 40 patients with lung cancer who were treated with conventional fractionated radiotherapy (CFRT). The 40 plans (divided into two groups with one or two target volumes) were completed by 9 planners using volumetric modulated arc therapy (VMAT). A planning strategy, including technique script for each group and a planning process for data collection, was introduced. The total planning time, number of optimizations, and dose-volume parameters of each plan were recorded and analyzed. A plan quality metric (PQM) was defined according to the clinical constraints. Statistical analysis of parameters of each plan following each optimization was performed for evaluating improvements in plan quality. RESULTS: According to the clinical plans generated by different planners, the median number of optimizations of each group was 4, and the median planning time was approximately 1 h (68.6 min and 62.0 min for plans with one or two target volumes, respectively). The dose deposited in organs at risk (OARs) gradually decreased, and the PQM values gradually improved following each optimization. The improvements were significant only between adjacent optimizations from the first optimization (Opt1) to the third optimization (Opt3). CONCLUSION: Increasing the number of optimizations was associated with significantly improved sparing of OARs with slight effects on the dose coverage and homogeneity of target volume. Generally, based on the designed planning strategy, there was no significant improvement of the plan quality for more than three optimizations.

9.
Int J Clin Exp Pathol ; 13(2): 192-202, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32211099

RESUMO

BACKGROUND: Hepatorenal and hepatopulmonary syndrome are common clinical diseases; however, their mechanisms have not been fully elucidated. Our aim was to determine whether liver injury by bile duct ligation (BDL) causes modifications in kidney and lung tissue in mice, and to explore the possible mechanism of these changes. METHODS: BDL in mice was used as a research model. Pathologic changes of liver, kidney, and lung tissue were observed by hematoxylin-eosin (H&E) staining. The expression of IGFBPrP1, NF-κB, TNF-α, and IL-6 were investigated in liver, kidney, and lung tissue by immunohistochemical staining and western blot. The correlation between IGFBPrP1 and NF-κB, TNF-α, and IL-6 protein expression in liver, kidney, and lung tissues of each group was analyzed by the Pearson method. RESULTS: H&E staining showed, after BDL administration in mice, different degrees of inflammatory change in liver, kidney, and lung tissues of mice in each group. The results of immunohistochemical staining and western blot analysis showed increased expressions of IGFBPrP1, NF-κB, TNF-α, and IL-6 after BDL. Pearson correlation analysis showed that IGFBPrP1 positively correlated with the expressions of NF-κB, TNF-α, and IL-6. CONCLUSION: Liver injury caused by bile duct ligation can lead to kidney and lung tissue injury in mice. The mechanism of injury may be related to the high expression of liver injury factor IGFBPrP1, transcription factor NF-κB, proinflammatory cytokine TNF-α, and IL-6 in kidney and lung tissue. Moreover, an increased expression level of IGFBPrP1 may be accompanied by the activation of the NF-κB inflammatory pathway.

10.
BMC Pediatr ; 20(1): 85, 2020 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-32087707

RESUMO

BACKGROUND: Extensive myocardial calcification has a low incidence rate, but when the patients do have extensive myocardial cases, the prognosis is usually poor. Several sepsis-related extensive myocardial calcification cases have been reported, but there are cases of biventricular calcifications that are caused by multiple cases besides bacteremia and the treatment for it has a low percentage of success. CASE PRESENTATION: A 9 year old girl had an extensive biventricular calcification which is caused by multiple factors including multiple organ failure (heart, lung, liver, and kidney), aseptic cardiomyopathy, systemic inflammatory response syndrome, pulmonary hemorrhage, viral encephalitis. In this case study, the massive myocardial calcification present in the patient was classified as dystrophic. After the patient was transferred to the Intensive care unit, a series of rescue treatments such as anti-inflammatory factor storm were implemented to protect the organs. In the end, the patient was rescued from the rescue treatment procedure. After 18 months of follow-up, it was observed that the patient's heart function returned to normal and it was observed that there was no change in myocardial calcification in the patient. CONCLUSION: In this case study, it showcased a case of the diffused biventricular calcification that caused by multiple factors. Furthermore, the precise role of calcification on cardiac function was largely unknown and there has to be further follow-up observation on the patient.

11.
Chemosphere ; 244: 125486, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31812050

RESUMO

There is a lack of research on microplastic pollution in freshwater areas. In this study, microplastic pollution in lakeshore sediments of East Dongting Lake was investigated. The abundance of microplastics ranged from 180 to 693 items/kg in the lakeshore sediment, which was moderate compared with other areas of the world. Fibers, transparent and small sized microplastics accounted for the largest proportion in terms of shape, color and size, respectively. Eight types of microplastics with different polymer compositions were identified by micro-Raman spectroscopy. The study found that the abundance of microplastics in the urban area sediment of Dongting Lake is lower than that of the rural area. The difference in environmental protection measures between urban and rural areas may be the cause of this phenomenon. The results of this study is helpful for understanding the role of human activities in microplastic pollution and provide valuable references for future research.


Assuntos
Monitoramento Ambiental , Microplásticos/análise , Poluentes Químicos da Água/análise , Conservação dos Recursos Naturais , Poluição Ambiental/análise , Sedimentos Geológicos/química , Lagos/química , Plásticos/química
12.
Materials (Basel) ; 12(21)2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31689963

RESUMO

Single phase ß-Si3N4 with microcrystals was synthesized via carbothermal reduction-nitridation (CRN) of quartz and carbon coke powder as starting materials. The effects of reaction parameters, i.e., heating temperature, holding time, C/SiO2 ratio, Fe2O3 additive and ß-Si3N4 seeds on the phase transformation and morphology of products were investigated and discussed. Rather than receiving a mixture of both α- and ß- phases of Si3N4 in the products, we synthesized powders of ß-Si3N4 single polymorph in this work. The mechanism for the CRN synthesis of ß-Si3N4 from quartz and the formation mechanism of Fe3Si droplets were discussed. We also firstly reported the formation of Fe3Si Archimedean solids from a CRN process where Fe2O3 was introduced as additive. Comparing to the gear-like short columnar morphology observed in samples without ß-Si3N4 seeding, the addition of ß-Si3N4 seeds led to an elongated morphology of final products and much finer widths. In addition, the ß-Si3N4 microcrystals exhibited a violet‒blue spectral emission range, which could be highly valuable for their future potential optoelectronic applications.

13.
Biotechnol Biofuels ; 12: 241, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31624503

RESUMO

Background: Limonene is an important biologically active natural product widely used in the food, cosmetic, nutraceutical and pharmaceutical industries. However, the low abundance of limonene in plants renders their isolation from plant sources non-economically viable. Therefore, engineering microbes into microbial factories for producing limonene is fast becoming an attractive alternative approach that can overcome the aforementioned bottleneck to meet the needs of industries and make limonene production more sustainable and environmentally friendly. Results: In this proof-of-principle study, the oleaginous yeast Yarrowia lipolytica was successfully engineered to produce both d-limonene and l-limonene by introducing the heterologous d-limonene synthase from Citrus limon and l-limonene synthase from Mentha spicata, respectively. However, only 0.124 mg/L d-limonene and 0.126 mg/L l-limonene were produced. To improve the limonene production by the engineered yeast Y. lipolytica strain, ten genes involved in the mevalonate-dependent isoprenoid pathway were overexpressed individually to investigate their effects on limonene titer. Hydroxymethylglutaryl-CoA reductase (HMGR) was found to be the key rate-limiting enzyme in the mevalonate (MVA) pathway for the improving limonene synthesis in Y. lipolytica. Through the overexpression of HMGR gene, the titers of d-limonene and l-limonene were increased to 0.256 mg/L and 0.316 mg/L, respectively. Subsequently, the fermentation conditions were optimized to maximize limonene production by the engineered Y. lipolytica strains from glucose, and the final titers of d-limonene and l-limonene were improved to 2.369 mg/L and 2.471 mg/L, respectively. Furthermore, fed-batch fermentation of the engineered strains Po1g KdHR and Po1g KlHR was used to enhance limonene production in shake flasks and the titers achieved for d-limonene and l-limonene were 11.705 mg/L (0.443 mg/g) and 11.088 mg/L (0.385 mg/g), respectively. Finally, the potential of using waste cooking oil as a carbon source for limonene biosynthesis from the engineered Y. lipolytica strains was investigated. We showed that d-limonene and l-limonene were successfully produced at the respective titers of 2.514 mg/L and 2.723 mg/L under the optimal cultivation condition, where 70% of waste cooking oil was added as the carbon source, representing a 20-fold increase in limonene titer compared to that before strain and fermentation optimization. Conclusions: This study represents the first report on the development of a new and efficient process to convert waste cooking oil into d-limonene and l-limonene by exploiting metabolically engineered Y. lipolytica strains for fermentation. The results obtained in this study lay the foundation for more future applications of Y. lipolytica in converting waste cooking oil into various industrially valuable products.

14.
Carbohydr Polym ; 219: 290-297, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151528

RESUMO

Microbial contamination has evolved as a life-threatening problem afflicting people due to various diseases caused by pathogenic bacteria in drinking water. Thus developing novel antibacterial materials is an urgent need. Herein, a chitosan (CTS)/ biochar-nanosilver (C-Ag) antibacterial composite was prepared by a method of CTS-coated on C-Ag obtained through a facile high-temperature carbonization process using corn straw as the carbon substrate. The results from FT-IR, XRD, SEM and TG-DSC revealed that the biochar loading spherical silver nanoparticles was coated with CTS in the composite. The antibacterial activity of the CTS/C-Ag composite was investigated using the plate counting method with Escherichia coli (E. coli), and the results suggest that the composite exhibited excellent antibacterial activity against E. coli. In this application study, it was proven that the CTS/C-Ag composite exhibits sustainable antibacterial activity and good reusability for drinking water. Therefore, the CTS/C-Ag composite has potential application in drinking water treatment.


Assuntos
Antibacterianos , Quitosana/farmacologia , Água Potável , Escherichia coli/efeitos dos fármacos , Nanocompostos/química , Purificação da Água/métodos , Antibacterianos/química , Antibacterianos/farmacologia , Carvão Vegetal/química , Quitosana/química , Água Potável/análise , Água Potável/microbiologia , Nanopartículas Metálicas/química , Extratos Vegetais/química , Prata/química , Zea mays/química
15.
Med Dosim ; 44(4): e80-e85, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30987867

RESUMO

To evaluate the performance of 2 methods predicting liver dosimetric indices for hepatocellular cancer patients treated with intensity modulated radiation therapy (IMRT). Two predicting methods were implemented to build correlation between geometric and dosimetric information of hepatocellular cancer IMRT plans. One method used Principle Component Analysis method to simplify information and Support Vector Machine (SVM) regression method to build correlation. The other method used a simple linear function to map volumes of certain regions to dosimetic indices. Thirty eight hepatocellular cancer IMRT plans were randomly selected to train the 2 methods. The effectiveness of the 2 methods was validated using another 8 plans. Liver dosimetric indices V10, V20, V30, and mean dose of the 8 plans in validation cohort were calculated using the predicting methods. The predicted indices were compared with the indices derived from the clinically accepted treatment plans. The absolute differences of V10 calculated with the SVM method and the actual values of treatment plans had a mean value of 7.87%. And the values for V20, V30, and mean dose were 4.37%, 4.41%, and 4.20%, respectively. The absolute differences of V10 calculated with the linear formulation method and the actual values of treatment plans had a mean value of 6.09%. And the values for V20, V30, and mean dose were 5.28%, 5.05%, and 5.92%, respectively. These 2 methods have similar accuracy in predicting dosimetric indices V10, V20, V30 of livers. The predicting of V30 and V20 is more accurate than the predicting of V10. The SVM method is more accurate in predicting mean liver dose.


Assuntos
Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Humanos , Órgãos em Risco/efeitos da radiação , Valor Preditivo dos Testes , Análise de Componente Principal , Proteção Radiológica/métodos , Radiometria , Máquina de Vetores de Suporte
16.
Med Phys ; 46(5): 1972-1983, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30870586

RESUMO

PURPOSE: To develop a deep learning method for prediction of three-dimensional (3D) voxel-by-voxel dose distributions of helical tomotherapy (HT). METHODS: Using previously treated HT plans as training data, a deep learning model named U-ResNet-D was trained to predict a 3D dose distribution. First, the contoured structures and dose volumes were converted from plan database to 3D matrix with a program based on a developed visualization toolkit (VTK), then transferred to U-ResNet-D for correlating anatomical features and dose distributions at voxel-level. One hundred and ninety nasopharyngeal cancer (NPC) patients treated by HT with multiple planning target volumes (PTVs) in different prescription patterns were studied. The model was typically trained from scratch with weights randomly initialized rather than using transfer-learning method, and used to predict new patient's 3D dose distributions. The predictive accuracy was evaluated with three methods: (a) The dose difference at the position r, δ(r, r) = Dc (r) - Dp (r), was calculated for each voxel. The mean (µÎ´(r,r) ) and standard deviation (σδ(r,r) ) of δ(r, r) were calculated to assess the prediction bias and precision; (b) The mean absolute differences of dosimetric indexes (DIs) including maximum and mean dose, homogeneity index, conformity index, and dose spillage for PTVs and organ at risks (OARs) were calculated and statistically analyzed with the paired-samples t test; (c) Dice similarity coefficients (DSC) between predicted and clinical isodose volumes were calculated. RESULTS: The U-ResNet-D model predicted 3D dose distribution accurately. For twenty tested patients, the prediction bias ranged from -2.0% to 2.3% and prediction error varied from 1.5% to 4.5% (relative to prescription) for 3D dose differences. The mean absolute dose differences for PTVs and OARs are within 2.0% and 4.2%, and nearly all the DIs for PTVs and OARs had no significant differences. The averaged DSC ranged from 0.95 to 1 for different isodose volumes. CONCLUSIONS: The study developed a new deep learning method for 3D voxel-by-voxel dose prediction, and shown to be able to produce accurately dose predictions for nasopharyngeal patients treated by HT. The predicted 3D dose map can be useful for improving radiotherapy planning design, ensuring plan quality and consistency, making clinical technique comparison, and guiding automatic treatment planning.


Assuntos
Aprendizado Profundo , Neoplasias Nasofaríngeas/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Nasofaríngeas/diagnóstico por imagem , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Tomografia Computadorizada por Raios X/métodos
17.
Med Dosim ; 44(4): e13-e18, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30529304

RESUMO

The present study aimed to compare 4 techniques in the planning of locoregional irradiation including internal mammary nodal region for left-sided breast cancer. Ten patients with left-sided breast cancer undergoing breast conservation surgery were enrolled. For each patient, 4 treatment plans were performed: a helical tomotherapy (HT) plan, a volumetric modulated arc therapy (VMAT) plan, a static intensity modulated radiation therapy (IMRT) plan, and a hybrid IMRT plan, designed to encompass the whole breast, internal mammary, and supraclavicular nodal regions. The prescribed dose of radiation was 50 Gy in 25 fractions. The dosimetric parameters of the target and organs at risk, as well as the dose delivery time, were evaluated and compared using an independent-samples t-test. The HT and VMAT plans had the best conformity and homogeneity. For the HT, VMAT, IMRT, and hybrid IMRT plans, the mean conformity index (CI) and homogeneity index (HI) were 0.83, 0.82, 0.8, and 0.77 (p < 0.001); and 1.07, 1.11, 1.14, and 1.14 (p < 0.001), respectively. The corresponding V55 values were 0.3%, 11.4%, 27.02%, and 23.29% (p < 0.001). The Dmean and V20 of the left lung obtained using the HT plan were significantly lower than those of VMAT, IMRT, and hybrid IMRT plans (p = 0.002, p = 0.004). There were no significant differences in D max of LAD descending coronary artery, or the Dmean of the heart among the 4 types of plans. The HT and VMAT plans had a lower dose to other organ at risk (OARs) compared with the IMRT and hybrid IMRT plans. The mean delivery times were 1042 ± 33 seconds, 136 ± 12 seconds, 450 ± 65 seconds, and 451 ± 70 seconds for the HT, VMAT, IMRT, and hybrid IMRT plans, respectively (p < 0.001). For whole breast plus supraclavicular and internal mammary nodal irradiation in left-sided breast cancer, the VMAT technique is recommended considering both the dose distribution and the delivery time. Under circumstances in which dose distribution is a priority, the HT technique is a valid option.


Assuntos
Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Neoplasias Unilaterais da Mama/radioterapia , Fracionamento da Dose de Radiação , Feminino , Humanos , Metástase Linfática/radioterapia , Mastectomia Segmentar , Órgãos em Risco/efeitos da radiação , Radiometria , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X , Neoplasias Unilaterais da Mama/cirurgia
18.
Sci Rep ; 8(1): 16771, 2018 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-30425262

RESUMO

Single-crystal MoO3 micrometer to millimeter even centimeter belts were prepared via a novel route of oxidizing a discarded molybdenum disilicide heating element at 1000 °C for 3 h. The morphology and structure features, and growth mechanism of the products were evidently investigated by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results indicated that the powdery and fibrous products were typical α-MoO3 belt-like structures which size could develop from micrometer to several millimeter even centimeter in length and up to 0.5 mm in width. It should be formed preferentially along the [001] direction via layer by layer growth to form 1-D single MoO3 belts by vapor-solid mechanism. Thermal and luminescence properties of the products were revealed by thermogravimetric analysis and differential thermal analysis and photoluminescence spectra that the resultant α-MoO3 belts had good thermal stability and characteristics of luminescence with a central peak at 481 nm. The MoO3 belts are of good potential being applied to luminescent and high temperature devices.

19.
Microb Cell Fact ; 17(1): 166, 2018 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-30359264

RESUMO

BACKGROUND: Microbial biofuel production provides a promising sustainable alternative to fossil fuels. 1-Butanol is recognized as an advanced biofuel and is gaining attention as an ideal green replacement for gasoline. In this proof-of-principle study, the oleaginous yeast Yarrowia lipolytica was first engineered with a heterologous CoA-dependent pathway and an endogenous pathway, respectively. RESULTS: The co-overexpression of two heterologous genes ETR1 and EutE resulted in the production of 1-butanol at a concentration of 65 µg/L. Through the overexpression of multiple 1-butanol pathway genes, the titer was increased to 92 µg/L. Cofactor engineering through endogenous overexpression of a glyceraldehyde-3-phosphate dehydrogenase and a malate dehydrogenase further led to titer improvements to 121 µg/L and 110 µg/L, respectively. In addition, the presence of an endogenous 1-butanol production pathway and a gene involved in the regulation of 1-butanol production was successfully identified in Y. lipolytica. The highest titer of 123.0 mg/L was obtained through this endogenous route by combining a pathway gene overexpression strategy. CONCLUSIONS: This study represents the first report on 1-butanol biosynthesis in Y. lipolytica. The results obtained in this work lay the foundation for future engineering of the pathways to optimize 1-butanol production in Y. lipolytica.


Assuntos
1-Butanol/metabolismo , Coenzima A/metabolismo , Yarrowia/metabolismo , Expressão Gênica , Engenharia Metabólica , Plasmídeos/metabolismo
20.
Cell Biol Int ; 42(11): 1564-1574, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30136751

RESUMO

Ovarian cancer is one of the most common gyneacologic malignancies, with high morbidity and high mortality. Hsa-miR-122-5p (miR-122) has been reported with tumor-suppressing roles in various cancers. In this study, miR-122 was overexpressed in ovarian cancer cells, and phenotypic experiments demonstrated that miR-122 inhibited migration and invasion in SKOV3 and OVCAR3 cells. MiR-122 also suppressed epithelial mesenchymal transition (EMT), evidenced by expression changes of E-cadherin, vimentin, matrix metalloproteinase (MMP)2, and MMP14. Prolyl-4-hydroxylase subunit alpha-1 (P4HA1) was identified as a target of miR-122, and downregulated by miR-122. MiR-122-induced the elevation of migration, invasion, and EMT were recovered by P4HA1. Additionally, miR-122 restrained the tumor metastasis of SKOV3 cells in peritoneal cavity of nude mice. In summary, we demonstrated that miR-122 inhibited migration, invasion, EMT, and metastasis in peritoneal cavity of ovarian cancer cells by targeting P4HA1 for the first time, which shed lights on the discovery of miR-122 and P4HA1 as possible potential diagnostic markers and therapeutic targets for ovarian cancer.


Assuntos
Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Pró-Colágeno-Prolina Dioxigenase/genética , Animais , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação para Baixo/genética , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/secundário , Fenótipo , Pró-Colágeno-Prolina Dioxigenase/metabolismo
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