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1.
Environ Res ; 250: 118494, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38365061

RESUMEN

Microplastics (MPs), the emerging pollutants appeared in water environment, have grabbed significant attention from researchers. The quantitative method of spherical MPs is the premise and key for the study of MPs in laboratory researches. However, the manual counting is time-consuming, and the existing semi-automated analysis lacked of robustness. In this study, a highly accurate quantification method for spherical MPs, called VS120-MC was proposed. VS120-MC consisted of the digital slide scanner VS120 and the MPs image processing software, MPs-Counter. The full-area scanning photography was employed to fundamentally avoid the error caused by random or partition sampling modes. To accomplish high-performance batch recognition, the Weak-Circle Elimination Algorithm (WEA) and the Variable Coefficient Threshold (VCT) was developed. Finally, lower than 0.6% recognition error rate of simulated images with different aggregated indices was achieved by MPs-Counter with fast processing speed (about 2 s/image). The smallest size for VS120-MC to detect was 1 µm. And the applicability of VS120-MC in real water body was investigated. The measured value of 1 µm spherical MPs in ultra-pure water and two kinds of polluted water after digestion showed a good linear relationship with the Manual measurements (R2 = 0.982,0.987 and 0.978, respectively). For 10 µm spherical MPs, R2 reached 0.988 for ultra-pure water and 0.984 for both of the polluted water. MPs-Counter also showed robustness when using the same set of parameters processing the images with different conditions. Overall, VS120-MC eliminated the error caused by traditional photography and realized an accurate, efficient, stable image processing tool, providing a reliable alternative for the quantification of spherical MPs.


Asunto(s)
Monitoreo del Ambiente , Procesamiento de Imagen Asistido por Computador , Microplásticos , Contaminantes Químicos del Agua , Microplásticos/análisis , Procesamiento de Imagen Asistido por Computador/métodos , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Monitoreo del Ambiente/instrumentación , Algoritmos
2.
BMC Public Health ; 24(1): 1364, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773444

RESUMEN

OBJECTIVE: Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) are considered gold standards for measuring visceral fat area (VFA). However, their relatively high prices and potential radiation exposure limit their widespread use in clinical practice and everyday life. Therefore, our study aims to develop a VFA estimated equation based on sagittal abdominal diameter (SAD) and transverse abdominal diameter (TAD) using anthropometric indexes. To the best of our knowledge, there have been limited studies investigating this aspect thus far. METHODS: This study was designed as a cross-sectional, retrospective cohort survey. A total of 288 patients (167 males and 121 females) aged 18-80 with type 2 diabetes (T2D) were consecutively collected from a multicenter hospital, and VFA was measured by CT. Subsequently, variables highly correlated with VFA were screened through general linear correlation analysis. A stepwise regression analysis was then conducted to develop a VFA estimated equation. Discrepancies between the estimated and actual VFA values were assessed using the Bland-Altman method to validate the accuracy of the equation. RESULTS: In the female T2D population, triglyceride (TG), SAD, TAD were found to be independently correlated with VFA; in the male T2D population, BMI, TG, SAD and TAD showed independent correlations with VFA. Among these variables, SAD exhibited the strongest correlation with VFA (r = 0.83 for females, r = 0.88 for males), followed by TAD (r = 0.69 for females, r = 0.79 for males). Based on these findings, a VFA estimated equation was developed for the T2D population: VFA (male) =-364.16 + 15.36*SAD + 0.77*TG + 9.41*TAD - 5.00*BMI (R2 = 0.75, adjusted R2 = 0.74); VFA(female)=-170.87 + 9.72*SAD-24.29*(TG^-1) + 3.93*TAD (R2 = 0.69, adjusted R2 = 0.68). Both models demonstrated a good fit. The Bland-Altman plot indicated a strong agreement between the actual VFA values and the estimated values, the mean differences were close to 0, and the majority of differences fell within the 95% confidence interval. CONCLUSIONS: In the T2D population, a VFA estimated equation is developed by incorporating SAD and TAD along with other measurement indices. This equation demonstrates a favorable estimated performance, suggesting to the development of novel and practical VFA estimation models in the future study.


Asunto(s)
Diabetes Mellitus Tipo 2 , Grasa Intraabdominal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Estudios Transversales , Grasa Intraabdominal/diagnóstico por imagen , Estudios Retrospectivos , Diámetro Abdominal Sagital , Tomografía Computarizada por Rayos X
3.
J Appl Clin Med Phys ; : e14460, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39072977

RESUMEN

PURPOSE: We aimed to show the framework of the six-sigma methodology (SSM) that can be used to determine the limits of QC tests for the linear accelerator (Linac). Limits for QC tests are individually determined using the SSM. METHODS AND MATERIALS: The SSM is based on the define-measure-analyze-improve-control (DMAIC) stages to improve the process. In the "define" stage, the limits of QC tests were determined. In the "measure" stage, a retrospective collection of daily QC data using a Machine Performance Check platform was performed from January 2020 to December 2022. In the "analyze" stage, the process of determining the limits was proposed using statistical analyses and process capability indices. In the "improve" stage, the capability index was used to calculate the action limits. The tolerance limit was established using the larger one of the control limits in the individual control chart (I-chart). In the "control" stage, daily QC data were collected prospectively from January 2023 to May 2023 to monitor the effect of action limits and tolerance limits. RESULTS: A total of 798 sets of QC data including beam, isocenter, collimation, couch, and gantry tests were collected and analyzed. The Collimation Rotation offset test had the min-Cp, min-Cpk, min-Pp, and min-Ppk at 2.53, 1.99, 1.59, and 1.25, respectively. The Couch Rtn test had the max-Cp, max-Cpk, max-Pp, and max-Ppk at 31.5, 29.9, 23.4, and 22.2, respectively. There are three QC tests with higher action limits than the original tolerance. Some data on the I-chart of the beam output change, isocenter KV offset, and jaw X1 exceeded the lower tolerance and action limit, which indicated that a system deviation occurred and reminded the physicist to take action to improve the process. CONCLUSIONS: The SSM is an excellent framework to use in determining the limits of QC tests. The process capability index is an important parameter that provides quantitative information on determining the limits of QC tests.

4.
J Oral Rehabil ; 51(3): 611-622, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37962287

RESUMEN

BACKGROUND: Regulation of redox homeostasis could reduce osteoarthritis severity and limit disease progression, while glycyrrhizin (GL) shows great antioxidant and anti-inflammatory capacity. OBJECTIVE: The aim of this study was to investigate the role of GL on oxidative stress and the potential regulatory mechanism in rat temporomandibular joint (TMJ) chondrocytes under oxidative stress, and investigate the effect of GL in the rat temporomandibular joint osteoarthritis (TMJOA) model. METHODS: Rat TMJ chondrocytes were cultured in oxidative stress with different doses of GL. The effect of glycyrrhizin on the nuclear factor-erythroid 2-related factor 2 (Nrf2) in oxidative stress was evaluated by western blot and immunofluorescence staining. A rat model of TMJOA was treated with GL. Micro-computed tomography, histological and immunohistochemical analysis were used to assess the pathological change of TMJOA. RESULTS: The expression of superoxide dismutase 1 (SOD1), heme oxygenase-1 (HO-1), and peroxiredoxin 6 (PRDX6) were decreased, and intracellular Nrf2 signaling pathway was activated in chondrocytes in oxidative stress. GL upregulates the expression of antioxidants, especially PRDX6, as well as increases Nrf2 expression and nuclear translocation in rat condylar chondrocytes. Administration of GL attenuates condylar bone destruction, cartilage degeneration, and synovitis in rats TMJOA. Meanwhile, GL alleviated oxidative stress and enhanced the antioxidant capacity of TMJOA cartilage. CONCLUSION: This study suggested that GL alleviates rat TMJOA by regulating oxidative stress in condylar cartilage.


Asunto(s)
Cartílago Articular , Osteoartritis , Animales , Ratas , Antioxidantes/farmacología , Antioxidantes/metabolismo , Cartílago Articular/patología , Condrocitos/metabolismo , Ácido Glicirrínico/metabolismo , Ácido Glicirrínico/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Osteoartritis/tratamiento farmacológico , Transducción de Señal , Articulación Temporomandibular/patología , Microtomografía por Rayos X
5.
Inorg Chem ; 62(8): 3541-3554, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36791307

RESUMEN

Construction of three-dimensional (3D) flower-like nanostructures with controlled morphologies has emerged as an attractive tool by scientists in the marine electric field sensor research field due to their peculiar structural features. Herein, novel 3D flower-like Ag-CF capacitive composite electrodes have been created by an eco-friendly water-bath strategy via AgNO3 as a sliver source and subsequently compounded with carbon fibers (CFs) pretreated by thermal oxidation. A series of electrode samples with various morphologies obtained by modulating different reaction times and temperatures bring about the dominant formation mechanism of these nanostructures and the influence behavior on the CF electrode in detail. Especially, the 3D flower-like Ag-CF electrode shows a large surface area acquired under the conditions of 80 °C and 15 min, which can provide more electroactive sites in electrochemical analysis and exhibit a maximum areal specific capacitance of 619.75 mF·cm-2 at a scanning speed of 10 mV·s-1. This is mainly due to the synergistic behavior of the unique 3D flower-like morphology and the large specific surface area of CFs. Furthermore, a cylinder-shaped Ag-CF sensor is designed, which delivers a superior potential difference of 33.08 µV, a potential difference drift of 18.62 µV/24 h for 30 days, and a self-noise of 0.92 nV/rt (Hz)@1 Hz. In this work, the intriguing synthesis strategy can be a promising facile approach to manufacture the controllable 3D flower-like Ag-CF electrode for electric field sensor applications.

6.
Cell Mol Life Sci ; 79(7): 370, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35725948

RESUMEN

Germ cell formation and embryonic development require ATP synthesized by mitochondria. The dynamic system of the mitochondria, and in particular, the fusion of mitochondria, are essential for the generation of energy. Mitofusin1 and mitofusin2, the homologues of Fuzzy onions in yeast and Drosophila, are critical regulators of mitochondrial fusion in mammalian cells. Since their discovery mitofusins (Mfns) have been the source of significant interest as key influencers of mitochondrial dynamics, including membrane fusion, mitochondrial distribution, and the interaction with other organelles. Emerging evidence has revealed significant insight into the role of Mfns in germ cell formation and embryonic development, as well as the high incidence of reproductive diseases such as asthenospermia, polycystic ovary syndrome, and gestational diabetes mellitus. Here, we describe the key mechanisms of Mfns in mitochondrial dynamics, focusing particularly on the role of Mfns in the regulation of mammalian fertility, including spermatogenesis, oocyte maturation, and embryonic development. We also highlight the role of Mfns in certain diseases associated with the reproductive system and their potential as therapeutic targets.


Asunto(s)
Fertilidad , GTP Fosfohidrolasas , Mitocondrias , Proteínas Mitocondriales , Animales , Drosophila/metabolismo , Femenino , GTP Fosfohidrolasas/metabolismo , Masculino , Mamíferos/metabolismo , Fusión de Membrana , Mitocondrias/metabolismo , Dinámicas Mitocondriales , Proteínas Mitocondriales/metabolismo
7.
J Cell Mol Med ; 26(3): 925-936, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34953035

RESUMEN

To investigate the role of glycyrrhizin on the progression of temporomandibular joint osteoarthritis (TMJOA) and the underlying mechanism by regulation of the high-mobility group box 1 (HMGB1) receptor for advanced glycation end products (RAGE)/toll-like receptor 4 (TLR4)-nuclear factor kappa B (NF-κB)/protein kinase B (AKT) pathway. After a rat model of TMJOA was built by intra-articular injection of monosodium iodoacetate, glycyrrhizin was intragastrically administered at low concentration (20 mg/kg) or high concentration (50 mg/kg). Micro-computed tomography, histological and immunohistochemical analysis were used to reveal the progression of TMJOA. Rat TMJ chondrocytes and disc cells were cultured in inflammatory condition with different doses of glycyrrhizin. Western blot was used to evaluate the effect of glycyrrhizin on the HMGB1-RAGE/TLR4-NF-κB/AKT pathway. Administration of glycyrrhizin alleviated cartilage degeneration, lowered the levels of inflammatory and catabolic mediators and reduced the production of HMGB1, RAGE and TLR4 in TMJOA animal model. Increased production of RAGE and TLR4, and activated intracellular NF-κB and/or AKT signalling pathways in chondrocytes and disc cells were found in inflammatory condition. Upon activation, matrix metalloprotease-3 and interleukin-6 were upregulated. Glycyrrhizin inhibited not only HMGB1 release but also RAGE and TLR4 in inflammatory condition. Glycyrrhizin alleviated the pathological changes of TMJOA by regulating the HMGB1-RAGE/TLR4-NF-kB/AKT signalling pathway. This study revealed the potential of glycyrrhizin as a novel therapeutic drug to suppress TMJ cartilage degradation.


Asunto(s)
Proteína HMGB1 , Osteoartritis , Animales , Ácido Glicirrínico/farmacología , Proteína HMGB1/metabolismo , FN-kappa B/metabolismo , Osteoartritis/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-akt , Ratas , Receptor para Productos Finales de Glicación Avanzada , Articulación Temporomandibular/metabolismo , Receptor Toll-Like 4/metabolismo , Microtomografía por Rayos X
8.
Eur J Oral Sci ; 130(3): e12863, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35342996

RESUMEN

The contribution of biomechanical factors in the formation of proximal contact loss has been observed, but there is little research on the mechanisms by which they contribute. Using finite element analysis, this study aimed to analyse the impact of bone quality on the biomechanical behaviour of a dentition consisting of implant prostheses and adjacent teeth. The occlusal load was applied on the implant/tooth crown. In the mesiodistal direction, the adjacent natural tooth mesially to the implant denture had the tendency for mesial movement, while the distal adjacent natural tooth had the tendency for distal movement. For the supporting bone around the mesial adjacent tooth, the maximum/minimum principal stress and strain values on the mesial side of the bone were higher than those on the distal side of the bone. Stress and strain values on the mesial side of the supporting bone around the distal adjacent tooth were lower than those on the distal side. With decreasing bone density, displacements of teeth and the implant denture, principal stresses and equivalent strains on tooth supporting bone increased. Studies on biomechanical behaviours of a tooth-implant dentition may provide a deeper understanding of implant-induced dental adaptive processes such as proximal contact loss.


Asunto(s)
Implantes Dentales , Boca Edéntula , Fenómenos Biomecánicos , Prótesis Dental de Soporte Implantado , Análisis del Estrés Dental , Análisis de Elementos Finitos , Humanos
9.
Int J Mol Sci ; 23(20)2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36292916

RESUMEN

The Polled Celtic (Pc) mutation locus is a genetically simple single mutation that is the best choice for breeding polled cattle using gene editing. However, the mechanism of the Pc locus for regulating horn development is unclear, so we used gene editing, somatic cell nuclear transfer and embryo transfer to obtain polled Holstein fetal bovine (gestation time 90 days) with a homozygous Pc insertion (gene-edited Holstein fetal bovine, EH) and the wild-type 90 days Holstein fetal bovine (WH) as controls. The hematoxylin-eosin (HE) staining results showed that, compared to the WH, the EH horn buds had no white keratinized projections or vacuolated keratinocytes and no thick nerve bundles under the dermal tissue. Furthermore, DNA sequencing results showed that the Pc locus was homozygously inserted into the fetal bovine genome. A total of 791 differentially expressed genes were identified by transcriptome sequencing analysis. Enrichment analysis and protein interaction analysis results of differentially expressed genes showed that abundant gene changes after Pc insertion were associated with the adhesion molecule regulation, actin expression, cytoskeletal deformation and keratin expression and keratinization. It was also noted that the results contained several genes that had been reported to be associated with the development of horn traits, such as RXFP2 and TWIST1. This study identified these changes for the first time and summarized them. The results suggested that the Pc mutant locus may inhibit neural crest cell EMT generation and keratin expression, leading to failures in neural crest cell migration and keratinization of the horn bud tissue, regulating the production of the polled phenotype.


Asunto(s)
Cuernos , Bovinos , Animales , Cuernos/fisiología , Edición Génica , Actinas , Eosina Amarillenta-(YS) , Hematoxilina , Queratinas , ARN
10.
BMC Cancer ; 21(1): 1185, 2021 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-34742270

RESUMEN

BACKGROUND: Various randomized trials have demonstrated that postmastectomy radiotherapy (RT) to the chest wall and comprehensive regional nodal areas improves survival in patients with axillary node-positive breast cancer. Controversy exists as to whether the internal mammary node (IMN) region is an essential component of regional nodal irradiation. Available data on the survival benefit of IMN irradiation (IMNI) are conflicting. The patient populations enrolled in previous studies were heterogeneous and most studies were conducted before modern systemic treatment and three-dimensional (3D) radiotherapy (RT) techniques were introduced. This study aims to assess the efficacy and safety of IMNI in the context of modern systemic treatment and computed tomography (CT)-based RT planning techniques. METHODS: POTENTIAL is a prospective, multicenter, open-label, parallel, phase III, randomized controlled trial investigating whether IMNI improves disease-free survival (DFS) in high-risk breast cancer with positive axillary nodes (pN+) after mastectomy. A total of 1800 patients will be randomly assigned in a 1:1 ratio to receive IMNI or not. All patients are required to receive ≥ six cycles of anthracycline and/or taxane-based chemotherapy. Randomization will be stratified by institution, tumor location (medial/central vs. other quadrants), the number of positive axillary nodes (1-3 vs. 4-9 vs. ≥10), and neoadjuvant chemotherapy (yes vs. no). Treatment will be delivered with CT-based 3D RT techniques, including 3D conformal RT, intensity-modulated RT, or volumetric modulated arc therapy. The prescribed dose is 50 Gy in 25 fractions or 43.5 Gy in 15 fractions. Tiered RT quality assurance is required. After RT, patients will be followed up at regular intervals. Oncological and toxilogical outcomes, especially cardiac toxicities, will be assessed. DISCUSSION: This trial design is intended to overcome the limitations of previous prospective studies by recruiting patients with pN+ breast cancer, using DFS as the primary endpoint, and prospectively assessing cardiac toxicities and requiring RT quality assurance. The results of this study will provide high-level evidence for elective IMNI in patients with breast cancer after mastectomy. TRIAL REGISTRATION: ClinicalTrails.gov , NCT04320979 . Registered 25 Match 2020, https://clinicaltrials.gov/ct2/show/NCT04320979.


Asunto(s)
Neoplasias de la Mama/radioterapia , Irradiación Linfática , Metástasis Linfática/radioterapia , Antraciclinas/uso terapéutico , Antineoplásicos/uso terapéutico , Axila , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Hidrocarburos Aromáticos con Puentes/uso terapéutico , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Metástasis Linfática/diagnóstico por imagen , Mastectomía , Cuidados Posoperatorios/métodos , Estudios Prospectivos , Planificación de la Radioterapia Asistida por Computador , Radioterapia Conformacional/métodos , Taxoides/uso terapéutico , Tomografía Computarizada por Rayos X
11.
Environ Res ; 193: 110560, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33279493

RESUMEN

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.


Asunto(s)
Nitrógeno , Vanadio , Catálisis , Luz , Titanio
12.
BMC Pediatr ; 20(1): 85, 2020 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-32087707

RESUMEN

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.


Asunto(s)
Calcinosis , Cardiomiopatías , Coagulación Intravascular Diseminada , Calcinosis/diagnóstico por imagen , Calcinosis/etiología , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/etiología , Niño , Femenino , Ventrículos Cardíacos , Humanos , Insuficiencia Multiorgánica
13.
J Ind Microbiol Biotechnol ; 47(12): 1083-1097, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33191463

RESUMEN

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.


Asunto(s)
Fermentación , Limoneno , Ácido Mevalónico , Saccharomyces cerevisiae , Bebidas Alcohólicas , Liasas Intramoleculares , Limoneno/metabolismo , Ingeniería Metabólica , Ácido Mevalónico/metabolismo , Monoterpenos/metabolismo , Fosfatos de Poliisoprenilo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
14.
J Ind Microbiol Biotechnol ; 47(6-7): 511-523, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32495196

RESUMEN

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.


Asunto(s)
Bebidas , Limoneno/metabolismo , Ingeniería Metabólica , Saccharomyces cerevisiae/metabolismo , Dimetilaliltranstransferasa/metabolismo , Fermentación , Microbiología Industrial , Liasas Intramoleculares/metabolismo , Fosfatos de Poliisoprenilo/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
15.
J Appl Clin Med Phys ; 21(6): 33-43, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32237271

RESUMEN

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.


Asunto(s)
Neoplasias Pulmonares , Radioterapia de Intensidad Modulada , Humanos , Neoplasias Pulmonares/radioterapia , Órganos en Riesgo , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador
16.
Microb Cell Fact ; 17(1): 166, 2018 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-30359264

RESUMEN

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.


Asunto(s)
1-Butanol/metabolismo , Coenzima A/metabolismo , Yarrowia/metabolismo , Expresión Génica , Ingeniería Metabólica , Plásmidos/metabolismo
17.
Cell Biol Int ; 42(11): 1564-1574, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30136751

RESUMEN

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.


Asunto(s)
Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , MicroARNs/metabolismo , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Procolágeno-Prolina Dioxigenasa/genética , Animales , Secuencia de Bases , Línea Celular Tumoral , Movimiento Celular/genética , Regulación hacia Abajo/genética , Femenino , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/genética , Invasividad Neoplásica , Metástasis de la Neoplasia , Neoplasias Peritoneales/patología , Neoplasias Peritoneales/secundario , Fenotipo , Procolágeno-Prolina Dioxigenasa/metabolismo
18.
J Ind Microbiol Biotechnol ; 44(11): 1541-1550, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28856461

RESUMEN

As a byproduct of yeast valine metabolism during fermentation, diacetyl can produce a buttery aroma in wine. However, high diacetyl concentrations generate an aromatic off-flavor and poor quality in wine. 2,3-Butanediol dehydrogenase encoded by BDH1 can catalyze the two reactions of acetoin from diacetyl and 2,3-butanediol from acetoin. BDH2 is a gene adjacent to BDH1, and these genes are regulated reciprocally. In this study, BDH1 and BDH2 were overexpressed in Saccharomyces uvarum to reduce the diacetyl production of wine either individually or in combination. Compared with those in the host strain WY1, the diacetyl concentrations in the recombinant strains WY1-1 with overexpressed BDH1, WY1-2 with overexpressed BDH2 alone, and WY1-12 with co-overexpressed BDH1 and BDH2 were decreased by 39.87, 33.42, and 46.71%, respectively. BDH2 was only responsible for converting diacetyl into acetoin, but not for the metabolic pathway of acetoin to 2,3-butanediol in S. uvarum. This study provided valuable insights into diacetyl reduction in wine.


Asunto(s)
Diacetil/análisis , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Saccharomyces/genética , Saccharomyces/metabolismo , Vino/análisis , Acetoína/metabolismo , Butileno Glicoles/metabolismo , Medios de Cultivo/química , Fermentación , Manipulación de Alimentos , Microbiología de Alimentos , Proteínas Fúngicas/metabolismo , Redes y Vías Metabólicas , Plásmidos/genética , Plásmidos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Compuestos Orgánicos Volátiles/análisis
19.
Front Oncol ; 14: 1339126, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38420019

RESUMEN

Purpose: Brain metastasis is a common, life-threatening neurological problem for patients with cancer. Single-isocenter volumetric modulated arc therapy (VMAT) has been popularly used due to its highly conformal dose and short treatment time. Accurate prediction of its dose distribution can provide a general standard for evaluating the quality of treatment plan. In this study, a deep learning model is applied to the dose prediction of a single-isocenter VMAT treatment plan for radiotherapy of multiple brain metastases. Method: A U-net with residual networks (U-ResNet) is employed for the task of dose prediction. The deep learning model is first trained from a database consisting of hundreds of historical treatment plans. The 3D dose distribution is then predicted with the input of the CT image and contours of regions of interest (ROIs). A total of 150 single-isocenter VMAT plans for multiple brain metastases are used for training and testing. The model performance is evaluated based on mean absolute error (MAE) and mean absolute differences of multiple dosimetric indexes (DIs), including (D max and D mean) for OARs, (D 98, D 95, D 50, and D 2) for PTVs, homogeneity index, and conformity index. The similarity between the predicted and clinically approved plan dose distribution is also evaluated. Result: For 20 tested patients, the largest and smallest MAEs are 3.3% ± 3.6% and 1.3% ± 1.5%, respectively. The mean MAE for the 20 tested patients is 2.2% ± 0.7%. The mean absolute differences of D 98, D 95, D 50, and D2 for PTV60, PTV52, PTV50, and PTV40 are less than 2.5%, 3.0%, 2.0%, and 3.0%, respectively. The prediction accuracy of OARs for D max and D mean is within 3.2% and 1.2%, respectively. The average DSC ranges from 0.86 to 1 for all tested patients. Conclusion: U-ResNet is viable to produce accurate dose distribution that is comparable to those of the clinically approved treatment plans. The predicted results can be used to improve current treatment planning design, plan quality, efficiency, etc.

20.
J Hazard Mater ; 469: 133957, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38452678

RESUMEN

Electro-peroxone (EP) is a novel technique for the removal of refractory organic contaminants (ROCs), while the role of anode in this system is neglected. In this work, the EP system with graphite felt anode (EP-GF) and activated carbon fiber anode (EP-ACF) was developed to enhance ibuprofen (IBP) removal. The results showed that 91.2% and 98.6% of IBP was removed within 20 min in EP-GF and EP-ACF, respectively. Hydroxy radical (O⋅H) was identified as the dominant reactive species, contributing 80.9% and 54.0% of IBP removal in EP-ACF and EP-GF systems, respectively. The roles of adsorption in EP-ACF and direct electron transfer in EP-GF cannot be ignored. Due to the differences in mechanism, EP-GF and EP-ACF systems were suitable for the removal of O⋅H-resistant ROCs (e.g., oxalic acid and pyruvic acid) and non-O⋅H-resistant ROCs (e.g., IBP and nitrobenzene), respectively. Both systems had excellent stability relying on the introduction of oxygen functional groups on the anode, and their electrolysis energy consumption was significantly lower than that of EP-Pt system. The three degradation pathways of IBP were proposed, and the toxicity of intermediates were evaluated. In general, carbon anodes have a good application prospect in the removal of ROCs in EP systems.

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