Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
1.
BJOG ; 130(2): 222-230, 2023 01.
Article in English | MEDLINE | ID: mdl-36056595

ABSTRACT

OBJECTIVE: We evaluated whether radiomic features extracted from planning computed tomography (CT) scans predict clinical end points in patients with locally advanced cervical cancer (LACC) undergoing intensity-modulated radiation therapy and brachytherapy. DESIGN: A retrospective cohort study. SETTING: Xiangya Hospital of Central South University, Changsha, Hunan, China. POPULATION: Two hundred and fifty-seven LACC patients who were treated with intensity-modulated radiotherapy from 2014 to 2017. METHODS: Patients were allocated into the training/validation sets (3:1 ratio) using proportional random sampling, resulting in the same proportion of groups in the two sets. We extracted 254 radiomic features from each of the gross target volume, pelvis and sacral vertebrae. The sequentially backward elimination support vector machine algorithm was used for feature selection and end point prediction. MAIN OUTCOMES AND MEASURES: Clinical end points include tumour complete response (CR), 5-year overall survival (OS), anaemia, and leucopenia. RESULTS: A combination of ten clinicopathological parameters and 34 radiomic features performed best for predicting CR (validation balanced accuracy: 80.8%). The validation balanced accuracy of 54 radiomic features was 85.8% for OS, and their scores can stratify patients into the low-risk and high-risk groups (5-year OS: 95.5% versus 36.4%, p < 0.001). The clinical and radiomic models were also predictive of anaemia and leucopenia (validation balanced accuracies: 71.0% and 69.9%). CONCLUSION: This study demonstrated that combining clinicopathological parameters with CT-based radiomics may have value for predicting clinical end points in LACC. If validated, this model may guide therapeutic strategy to optimise the effectiveness and minimise toxicity or treatment for LACC.


Subject(s)
Uterine Cervical Neoplasms , Female , Humans , Uterine Cervical Neoplasms/diagnostic imaging , Uterine Cervical Neoplasms/radiotherapy , Uterine Cervical Neoplasms/pathology , Retrospective Studies , Tomography, X-Ray Computed/methods , Treatment Outcome , Pelvis
2.
Nanotechnology ; 30(6): 065702, 2019 Feb 08.
Article in English | MEDLINE | ID: mdl-30524048

ABSTRACT

The effect of 2D quenching on single chain photophysics was investigated by spin coating 13 nm thick films of polystyrene lightly doped with MEH-PPV onto CVD grown graphene and observing the changes in several photoluminescent (PL) observables. With 99% of the PL quenched, we found a 60% drop in the PL lifetime, along with a significant blue-shift of the PL emission due to the preferential quenching of emission at longer wavelengths. During photo-bleaching, the blue spectral shift observed for isolated polymers was eliminated in the presence of the quencher up until 70% of the polymer was photo-bleached. Results were interpreted using a static disorder induced conjugation length distribution model. The quencher, by opening up a new non-radiative decay channel, ensures that excitons do not have sufficient time to migrate to nearby lower energy chromophores. The reduction of energy transfer into the lowest-energy chromophores thus reduces their rate of photo-bleaching. Finally, the difference between the quenched and non-quenched spectra allows the rate of energy transfer along the polymer backbone to be estimated at ∼2 ns-1.

3.
J Ind Microbiol Biotechnol ; 45(2): 123-139, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29344811

ABSTRACT

Putrescine is widely used in the industrial production of bioplastics, pharmaceuticals, agrochemicals, and surfactants. Because the highest titer of putrescine is much lower than that of its precursor L-ornithine reported in microorganisms to date, further work is needed to increase putrescine production in Corynebacterium glutamicum. We first compared 7 ornithine decarboxylase genes and found that the Enterobacter cloacae ornithine decarboxylase gene speC1 was most suitable for putrescine production in C. glutamicum. Increasing NADPH availability and blocking putrescine oxidation and acetylation were chosen as targets for metabolic engineering. The putrescine producer C. glutamicum PUT4 was first constructed by deleting puo, butA and snaA genes, and replacing the fabG gene with E. cloacae speC1. After adaptive evolution with C. glutamicum PUT4, the evolved strain C. glutamicum PUT-ALE, which produced an 96% higher amount of putrescine compared to the parent strain, was obtained. The whole genome resequencing indicates that the SNPs located in the odhA coding region may be associated with putrescine production. The comparative proteomic analysis reveals that the pentose phosphate and anaplerotic pathway, the glyoxylate cycle, and the ornithine biosynthetic pathway were upregulated in the evolved strain C. glutamicum PUT-ALE. The aspartate family, aromatic, and branched chain amino acid and fatty acid biosynthetic pathways were also observed to be downregulated in C. glutamicum PUT-ALE. Reducing OdhA activity by replacing the odhA native start codon GTG with TTG and overexpression of cgmA or pyc458 further improved putrescine production. Repressing the carB, ilvH, ilvB and aroE expression via CRISPRi also increased putrescine production by 5, 9, 16 and 19%, respectively.


Subject(s)
Corynebacterium glutamicum/genetics , Putrescine/biosynthesis , Biosynthetic Pathways , Corynebacterium glutamicum/metabolism , Enterobacter cloacae/enzymology , Gene Deletion , Metabolic Engineering , NADP/metabolism , Ornithine/biosynthesis , Ornithine Decarboxylase/genetics , Polymorphism, Single Nucleotide , Proteomics
4.
Opt Express ; 25(20): 24242-24250, 2017 Oct 02.
Article in English | MEDLINE | ID: mdl-29041369

ABSTRACT

LED strip lighting can provide high quality uniform shadow-free diffuse lighting at low cost as numerous emission sources are controlled by a single transformer. Organic LEDs offer the additional advantages of UV free emission and, for visible light communication, picosecond fluorescent lifetimes allowing the whole visible spectrum to be used without filters. Using parameters determined experimentally for solid-state LED strip lighting and fluorescent lifetimes typical of organic phosphors as the input for a Monte Carlo based ray-tracing simulation, we evaluate the potential bandwidths obtainable for indoor communication. Our work suggests that raw data transfer rates of 4 to 10 Mbps are obtainable in a standard 5m by 5m by 3m room compatible with Internet of Things (IoT) applications.

5.
Appl Opt ; 55(3): 576-84, 2016 Jan 20.
Article in English | MEDLINE | ID: mdl-26835933

ABSTRACT

Understanding and optimizing light propagation and extraction in light-emitting systems, such as fluorescent chemical sensors, is important for the production of more efficient sensors. We apply Monte Carlo ray tracing to model the effects of one-dimensional perturbations of film thickness on the luminescent emission (spatial, directional, spectral) of a freestanding transparent polymer film embedded with luminescent chromophores. Such modification not only enhances light extraction but also allows its location and direction to be controlled. Optimization of the deformation geometry allows for a 3.6-fold increase in intensity for a far-field detector.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 1025-9, 2015 Apr.
Article in Japanese | MEDLINE | ID: mdl-26197595

ABSTRACT

Visible and near infrared spectroscopy is a proven technology to be widely used in identification and exploration of hydrocarbon energy sources with high spectral resolution for detail diagnostic absorption characteristics of hydrocarbon groups. The most prominent regions for hydrocarbon absorption bands are 1,740-1,780, 2,300-2,340 and 2,340-2,360 nm by the reflectance of oil sands samples. These spectral ranges are dominated by various C-H overlapping overtones and combination bands. Meanwhile, there is relatively weak even or no absorption characteristics in the region from 1,700 to 1,730 nm in the spectra of oil sands samples with low bitumen content. With the increase in oil content, in the spectral range of 1,700-1,730 nm the obvious hydrocarbon absorption begins to appear. The bitumen content is the critical parameter for oil sands reserves estimation. The absorption depth was used to depict the response intensity of the absorption bands controlled by first-order overtones and combinations of the various C-H stretching and bending fundamentals. According to the Pearson and partial correlation relationships of oil content and absorption depth dominated by hydrocarbon groups in 1,740-1,780, 2,300-2,340 and 2,340-2,360 nm wavelength range, the scheme of association mode was established between the intensity of spectral response and bitumen content, and then unary linear regression(ULR) and partial least squares regression (PLSR) methods were employed to model the equation between absorption depth attributed to various C-H bond and bitumen content. There were two calibration equations in which ULR method was employed to model the relationship between absorption depth near 2,350 nm region and bitumen content and PLSR method was developed to model the relationship between absorption depth of 1,758, 2,310, 2,350 nm regions and oil content. It turned out that the calibration models had good predictive ability and high robustness and they could provide the scientific basis for rapid estimation of oil content in oil sands in future.

7.
Aging (Albany NY) ; 16(1): 779-798, 2024 01 11.
Article in English | MEDLINE | ID: mdl-38217547

ABSTRACT

OBJECTIVE: Spindle pole body component 25 (SPC25) is an important cyclin involved in chromosome segregation and spindle dynamics regulation during mitosis. However, the role of SPC25 in lung adenocarcinoma (LAUD) is unclear. MATERIALS AND METHODS: The differential expression of SPC25 in tumor samples and normal samples was analyzed using TIMER, TCGA, GEO databases, and the correlation between its expression and clinicopathological features and prognosis in LUAD patients. Biological pathways that may be enriched by SPC25 were analyzed using GSEA. In vitro cell experiments were used to evaluate the effect of knocking down SPC25 expression on LUAD cells. Correlation analysis and differential analysis were used to assess the association of SPC25 expression with genes related to cell cycle, glycolysis, and ferroptosis. A ceRNA network involving SPC25 was constructed using multiple database analyses. RESULTS: SPC25 was highly expressed in LUAD, and its expression level could guide staging and predict prognosis. GSEA found that high expression of SPC25 involved multiple cell cycles and glycolytic pathways. Knocking down SPC25 expression significantly affected the proliferation, migration and apoptosis of LUAD cells. Abnormal SPC25 expression levels can affect cell cycle progression, glycolytic ability and ferroptosis regulation. A ceRNA network containing SPC25, SNHG15/hsa-miR-451a/SPC25, was successfully predicted and constructed. CONCLUSIONS: Our findings reveal the association of up-regulation of SPC25 in LUAD and its expression with clinical features, prognosis prediction, proliferation migration, cell cycle, glycolysis, ferroptosis, and ceRNA networks. Our results indicate that SPC25 can be used as a biomarker in LUAD therapy and a target for therapeutic intervention.


Subject(s)
Adenocarcinoma of Lung , Ferroptosis , Lung Neoplasms , Humans , Prognosis , RNA, Competitive Endogenous , Ferroptosis/genetics , Spindle Pole Bodies , Adenocarcinoma of Lung/genetics , Mitosis , Lung Neoplasms/genetics , Microtubule-Associated Proteins
8.
Aging (Albany NY) ; 16(4): 3934-3954, 2024 02 20.
Article in English | MEDLINE | ID: mdl-38382106

ABSTRACT

OBJECTIVE: The enzyme Aspartyl tRNA synthetase 2 (DARS2) is a crucial enzyme in the mitochondrial tRNA synthesis pathway, playing a critical role in maintaining normal mitochondrial function and protein synthesis. However, the role of DARS2 in ESCA is unclear. MATERIALS AND METHODS: Transcriptional data of pan-cancer and ESCA were downloaded from UCSC XENA, TCGA, and GEO databases to analyze the differential expression of DARS2 between tumor samples and normal samples, and its correlation with clinicopathological features of ESCA patients. R was used for GO, KEGG, and GSEA functional enrichment analysis of DARS2 co-expression and to analyze the connection of DARS2 with glycolysis and m6A-related genes. In vitro experiments were performed to assess the effects of interfering with DARS2 expression on ESCA cells. TarBase v.8, mirDIP, miRTarBase, ENCORI, and miRNet databases were used to analyze and construct a ceRNA network containing DARS2. RESULTS: DARS2 was overexpressed in various types of tumors. In vitro experiments confirmed that interfering with DARS2 expression significantly affected the proliferation, migration, apoptosis, cell cycle, and glycolysis of ESCA cells. DARS2 may be involved in multiple biological pathways related to tumor development. Furthermore, correlation and differential analysis revealed that DARS2 may regulate ESCA m6A modification through its interaction with METTL3 and YTHDF1. A ceRNA network containing DARS2, DLEU2/has-miR-30a-5p/DARS2, was successfully predicted and constructed. CONCLUSIONS: Our findings reveal the upregulation of DARS2 in ESCA and its association with clinical features, glycolysis pathway, m6A modification, and ceRNA network. These discoveries provide valuable insights into the molecular mechanisms underlying ESCA.


Subject(s)
Aspartate-tRNA Ligase , Carcinoma , Esophageal Neoplasms , Humans , Esophageal Neoplasms/genetics , Apoptosis/genetics , Cell Cycle , Methyltransferases
9.
Chem Asian J ; 18(6): e202201142, 2023 Mar 14.
Article in English | MEDLINE | ID: mdl-36710260

ABSTRACT

A combustion-assisted polyol reduction (CPR) method has been developed to deposit electrocatalytically efficient and transparent Pt counter electrodes (CEs) for bifacial dye-sensitized solar cells (DSSCs). Compared with conventional thermal decomposition of Pt precursors, CPR allows for a decrease in reduction temperature to 150 °C. The low-temperature processing is attributed to adding an organic fuel, acetylacetone (Hacac), which provides extra heat to lower reduction energy. In addition, the stable Pt complexes can simultaneously be formed in ethylene glycol (EG) and Hacac system, which leads to Pt nanoparticle size regulation. A ratio of Hacac to EG is optimized to achieve excellent electrocatalytic activity and high visible light transmittance for CEs. The bifacial DSSCs fabricated with CPR-Pt CEs (EG : Hacac=1 : 16) reach efficiencies of 6.71±0.16% and 6.41±0.15% in front and back irradiations, respectively.

10.
JMIR Mhealth Uhealth ; 8(6): e17337, 2020 06 24.
Article in English | MEDLINE | ID: mdl-32442140

ABSTRACT

BACKGROUND: With 15.6 million smokers, Vietnam is one of the top 10 largest cigarette-consuming countries in the world. Unfortunately, smoking cessation programs are still scarce in Vietnam. Mindfulness-based and text messaging-based interventions have been increasingly used in smoking cessation studies in developed countries, with promising results. Given the exponential growth of mobile phone usage in Vietnam in recent years, mobile health interventions could be a potential strategy to increase smoking cessation in Vietnam. However, substantial cultural adaptations are needed to optimize the effectiveness of these interventions among Vietnamese smokers. OBJECTIVE: This study aims to involve qualitative research to inform the development of a mindfulness-based text messaging smoking cessation intervention for Vietnamese smokers. METHODS: A total of 10 focus groups were conducted with 71 Vietnamese male smokers aged between 18 and 65 years (5-9 participants per focus group). Overall, 5 focus groups were conducted with smokers who had the intention to quit (ie, preparation stage of change in the transtheoretical model), and 5 focus groups were conducted with smokers who did not have the intention to quit (contemplation or precontemplation stage). The focus groups were audio recorded, transcribed verbatim, and analyzed using NVivo 12 software (QSR International). RESULTS: The major themes included smoking triggers, barriers and facilitators for quitting, the perceptions of text messaging and mindfulness approaches for smoking cessation, and suggestions for the development of a text messaging-based smoking cessation program. Common smoking triggers included stress, difficulties concentrating, and fatigue. Frequently encountering other people who were smoking was a common barrier to quitting. However, participants indicated that concerns about the harmful effects of smoking on themselves and their wives and children, and encouragement from family members could motivate them to quit. The participants preferred diverse message content, including information about the consequences of smoking, encouragement to quit, and tips to cope with cravings. They suggested that text messages be clear and concise and use familiar language. Most smokers perceived that mindfulness training could be useful for smoking cessation. However, some suggested that videos or in-person training may also be needed to supplement teaching mindfulness through text messages. CONCLUSIONS: This study provides important insights to inform the development of a text messaging-based smoking cessation program that incorporates mindfulness for Vietnamese male smokers. The results could also be useful for informing similar programs in other low- and middle-income countries.


Subject(s)
Mindfulness , Smoking Cessation , Text Messaging , Adolescent , Adult , Aged , Humans , Male , Middle Aged , Perception , Qualitative Research , Smoking , Vietnam/epidemiology , Young Adult
11.
Health Psychol Open ; 7(2): 2055102920967248, 2020.
Article in English | MEDLINE | ID: mdl-33173590

ABSTRACT

This review describes both magnitude and patterns of major behavioral risk factors for NCDs. Positive changes in tobacco use were identified, though this is far to meet the established expectation. Harmful alcohol consumption was reported, especially for males. Only small proportion of the population consumed an adequate amount of fruits and vegetables daily. Average salt intake was approximately doubled, in comparison to WHO's recommendations. Physical activity has shifted gradually negatively, but future trends are unpredictable. An organized surveillance system should be developed initially with adequate tools and public resources to maintain and ensure sustainability over time.

12.
Health Psychol Open ; 7(2): 2055102920967244, 2020.
Article in English | MEDLINE | ID: mdl-33194214

ABSTRACT

Smoking is a global health problem among health science students. The objectives of this study were to estimate the prevalence of smoking and to examine associated factors among health science students from five universities in Vietnam. Among 5946 participants (95.0% response rate), the smoking prevalence was 19.2% (95% CI:17.4-21.0%) among male students and 2.9% (95% CI:2.4-3.5%) among female students. In the multivariable regression models, significant factors for smoking were the perceived financial burden, the respondent's year in university, a non-self-determined motivation profile, self-reported depression and/or anxiety, the level of vigorous physical activity, and alcohol drinking.

13.
J Am Soc Echocardiogr ; 32(7): 876-883.e11, 2019 07.
Article in English | MEDLINE | ID: mdl-31029500

ABSTRACT

BACKGROUND: To facilitate differentiation between normal and abnormal values, it is necessary to correct echocardiographic measurements for physiologic variance induced by age, gender, and body size variables. METHODS: A total of 34 two-dimensional echocardiographic parameters were measured in 1,224 healthy Chinese adults with body mass index < 25.0 kg/m2. An optimized multivariate allometric model and scaling equations were first developed in 858 subjects (group A), and their reliability was then verified in the remaining 366 subjects (group B). The traditional single-variable isometric model in which parameters are linearly corrected by a single body size variable (height, weight, body mass index, or body surface area) was used for comparison. The success of correction was defined as the absence of significant correlations (r > 0.20, P < .05) between the corrected values and age or any body size variables, while maintaining high correlations (r > 0.80) between the corrected and uncorrected values. RESULTS: Before correction, all 34 parameters correlated significantly with one or more of the physiologic variables of age and body size and differed significantly between men and women on 29 parameters (85.3%) in both groups. The success rate of correction with the single-variable isometric model was only 11.0% (15 of 136 corrections due to four variable corrections used for each parameter), while use of the optimized multivariate allometric model successfully corrected all 34 parameters (100%) for physiologic variance induced by age and body size variables and eliminated the gender differences in 32 parameters (94.1%). A new set of reference values for corrected echocardiographic measurements independent of age, gender, and body size variables were established. CONCLUSIONS: The novel optimized multivariate allometric model developed in this study is superior to traditional the single-variable isometric model in the correction of echocardiographic parameters for physiologic effects of age, gender, and body size variables and thus should be encouraged in both scientific research and clinical practice.


Subject(s)
Echocardiography , Anthropometry , China , Female , Humans , Male , Mathematics , Middle Aged , Reference Values , Reproducibility of Results
14.
Iran J Public Health ; 47(6): 844-851, 2018 Jun.
Article in English | MEDLINE | ID: mdl-30087870

ABSTRACT

BACKGROUND: The aim of this study was to explore the associations of haplotypes of the glucose transporter 9 (SLC2A9) genes with type 2 diabetes mellitus (T2DM) complicated with hyperuricemia (HUA). METHODS: Overall, 608 Chinese males, enrolled from the Affiliated Hospital of Medical College of Qingdao University in 2009-2012, were genotyped. The subjects included 167 withT2DM (average age of onset (58.07±11.82 yr), 198 with HUA subjects (average age of onset (39.20±9.73) yr), 115 with T2DM complicated with HUA (average age of onset (51.24±10.09) yr), and 128 control subjects (average age (41.92±10.01) yr). Patients genotypes of the SNPs; including rs734553 was determined by PCR method. Each genotype was regressed assuming the co-dominant, dominant and the recessive models of inheritance with covariates of duration of total glucose, uric acid, urea nitrogen, triglyceride, cholesterol, and creatinine levels. RESULTS: Chi-square test revealed that rs734553polymorphism was both significantly associated with HUA as well as T2DM complicated HUA, but not with pure T2DM. After adjustment for age and gender, analysis showed that people with C allele had higher risk of HUA and T2DM complicated HUA than those without C allele. And none of the subjects had the homozygous genotype for SLC2A9 (CC). CONCLUSION: The SLC2A9 mutation increases the risk for T2DM complicated HUA in Chinese population, which suggested that intron variants between two relatively conserved exons could also be associated with diseases. In patients of T2DM complicated with HUA, the diagnosis and detection of SLC2A9 gene variants should be caused enough attention.

SELECTION OF CITATIONS
SEARCH DETAIL