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1.
Front Cell Infect Microbiol ; 14: 1418168, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988816

RESUMO

Exosomes are extracelluar vesicles that facilitate intercellular communication and are pivotal in post-transcriptional regulation within cellular gene regulatory networks, impacting pathogen dynamics. These vesicles serve as crucial regulators of immune responses, mediating cellular interactions and enabling the introduction of viral pathogenic regions into host cells. Exosomes released from virus-infected cells harbor diverse microRNAs (miRNAs), which can be transferred to recipient cells, thereby modulating virus infection. This transfer is a critical element in the molecular interplay mediated by exosomes. Additionally, the endosomal sorting complex required for transport (ESCRT) within exosomes plays a vital role in virus infection, with ESCRT components binding to viral proteins to facilitate virus budding. This review elucidates the roles of exosomes and their constituents in the invasion of host cells by viruses, aiming to shed new light on the regulation of viral transmission via exosomes.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte , Exossomos , Interações Hospedeiro-Patógeno , MicroRNAs , Viroses , Exossomos/metabolismo , Humanos , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Viroses/metabolismo , Viroses/virologia , MicroRNAs/metabolismo , MicroRNAs/genética , Animais , Vírus/patogenicidade , Vírus/metabolismo , Liberação de Vírus , Proteínas Virais/metabolismo , Proteínas Virais/genética
2.
Appl Opt ; 63(12): 3178-3185, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856464

RESUMO

Silicon photonics devices benefit greatly from a partially etched platform and inverse design. Herein, we propose a bi-layer polarization splitter and rotator with a topology pattern and demonstrate it on a silicon-on-insulator platform. Our device exhibits a significantly reduced physical footprint of only 2µm×6µm, compared to traditional directional couplers and tapered waveguides. The device accomplishes the functions of polarization conversion and separation in such a compact design without redundant tapered or bending waveguides. The tested minimum insertion loss with the fabrication batch reaches 0.57 and 0.67 dB for TE and TM modes, respectively. The TE mode demonstrates a wider bandwidth and lower ILs than the TM modes, averaging around 1 dB from 1530 to 1565 nm. The M modes exhibit approximately 2 dB ILs at the same wavelength range, decreasing to about 1 dB between 1565 and 1580 nm. Improved designs and fabrication conditions strongly suggest the potential for further performance enhancement in the device. This successful initiative validates the exceptional performance resulting from the integration of the partially etched platform and inverse design, providing valuable insights for future photonic integrated device designs.

3.
J Inflamm Res ; 17: 2459-2478, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681070

RESUMO

Introduction: Sepsis is a worldwide epidemic, with high morbidity and mortality. Cuproptosis is a form of cell death that is associated with a wide range of diseases. This study aimed to explore genes associated with cuproptosis in sepsis, construct predictive models and screen for potential targets. Methods: The LASSO algorithm and SVM-RFE model has been analysed the expression of cuproptosis-related genes in sepsis and immune infiltration characteristics and identified the marker genes under a diagnostic model. Gene-drug networks, mRNA-miRNA networks and PPI networks were constructed to screen for potential biological targets. The expression of marker genes was validated based on the GSE57065 dataset. Consensus clustering method was used to classify sepsis samples. Results: We found 381 genes associated with the development of sepsis and discovered significantly differentially expressed cuproptosis-related genes of 16 cell types in sepsis and immune infiltration with CD8/CD4 T cells being lower. NFE2L2, NLRP3, SLC31A1, DLD, DLAT, PDHB, MTF1, CDKN2A and DLST were identified as marker genes by the LASSO algorithm and the SVM-RFE model. AUC > 0.9 was constructed for PDHB and MTF1 alone respectively. The validation group data for PDHB (P=0.00099) and MTF1 (P=7.2e-14) were statistically significant. Consistent clustering analysis confirmed two subtypes. The C1 subtype may be more relevant to cellular metabolism and the C2 subtype has some relevance to immune molecules.The results of animal experiments showed that the gene expression was consistent with the bioinformatics analysis. Discussion: Our study systematically explored the relationship between sepsis and cuproptosis and constructed a diagnostic model. And, several cuproptosis-related genes may interfere with the progression of sepsis through immune cell infiltration.

4.
Radiother Oncol ; 195: 110259, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38548112

RESUMO

BACKGROUND AND AIMS: Radiotherapy is widely applied for lung adenocarcinoma (LUAD), while individualized differences led to different outcomes. This study aimed to establish a multi-gene risk scoring model to predict the benefits of LUAD patients from radiotherapy, based on different types of cell death respectively. RESULTS: Other than autophagy, pyroptosis, ferroptosis and Immunogenic cell death (ICD), the LUAD prognostic model based on apoptosis had the best performance, and the area under curves (AUCs) of the receiver operating curve (ROC) for 1-, 3-, and 5-year OS were 0.700,0.736,0.723,respectively. Such genes were involved as SLC7A5, EXO1, ABAT, NLRP1 and GAR1. Then patients were divided into high and low risk groups by the median apoptosis-LUAD risk score. For patients in the high-risk group, i.e., the radiotherapy-tolerant group, we screened adjuvant chemotherapy and found that besides the conventional first-line chemotherapy regimen, drugs such as Fludarabine, Pevonedistat, and Podophyllotoxin Bromide may also have potential therapeutic value. CONCLUSION: The multi-gene risk scoring model based on apoptosis might predict the radiotherapy benefits of LUAD patients and for those radioresistant patients classified by the model we also provided effective adjuvant chemicals, which would be used to guide clinical treatment.


Assuntos
Adenocarcinoma de Pulmão , Apoptose , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/radioterapia , Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patologia , Prognóstico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Tolerância a Radiação/genética , Morte Celular
5.
Light Sci Appl ; 13(1): 20, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233396

RESUMO

A highly efficient second-harmonic source is integrated into a silicon nitride microring resonator, unlocking the potential for advanced chip-scale devices such as miniaturized atomic clocks and fully integrated self-referenced microcombs.

6.
Food Funct ; 14(24): 10841-10854, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37982854

RESUMO

Objectives: Fine particulate matter (PM2.5), a small molecule particulate pollutant, can reach the lungs via respiration and cause lung damage. Currently, effective strategies and measures are lacking to prevent and treat the pulmonary toxicity of PM2.5. Astaxanthin (ASX), a natural xanthophyll carotenoid, has attracted attention due to its unique biological activity. Our research aims to probe into the prevention and treatment of ASX on PM2.5-induced lung injury and clarify its potential mechanism. Methods: Sprague-Dawley (SD) rats were given olive oil and different concentrations of ASX orally daily for 21 days. PM2.5 suspension was instilled into the trachea of rats every two days for one week to successfully develop the PM2.5 exposure model in the PM2.5-exposed and ASX-treated groups of rats. The bronchoalveolar lavage fluid (BALF) was collected, and the content of lung injury-related markers was detected. Histomorphological changes and expression of markers associated with oxidative stress, inflammation, iron death, and apoptosis were detected in lung tissue. Results: PM2.5 exposure can cause changes in lung histochemistry and increase the expression levels of TP, AKP, ALB, and LDH in the BALF. Simultaneously, inflammatory responses and oxidative stress were promoted in rat lung tissue after exposure to particulate matter. Additionally, ASX preconditioning can alleviate histomorphological changes, oxidative stress, and inflammation caused by PM2.5 and reduce PM2.5-related ferroptosis and apoptosis. Conclusion: ASX preconditioning can alleviate lung injury after PM2.5 exposure by inhibiting ferroptosis and apoptosis.


Assuntos
Ferroptose , Lesão Pulmonar , Ratos , Animais , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/tratamento farmacológico , Lesão Pulmonar/metabolismo , Material Particulado/toxicidade , Ratos Sprague-Dawley , Pulmão , Xantofilas/farmacologia , Inflamação/metabolismo , Apoptose
7.
Opt Lett ; 48(18): 4893-4896, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37707930

RESUMO

All polarization-maintaining (PM) linear cavity mode-locked fiber lasers are promising ultrafast laser sources due to their compactness and environmental robustness. Here, we demonstrate a linear cavity fiber laser with all-PM configuration experimentally and investigate the mode-locking formation of the laser using a machine-learning iterative optimization method based on the Gaussian process. The optimization algorithm can converge rapidly after only 30 runs. Using the optimized parameters, we simulate the generation of mode-locked pulses from noise. The output spectrum and pulse energy are highly consistent with the experiment. Furthermore, we describe the intracavity dynamic evolution under group velocity mismatch. We then show that the pulse trapping induced by cross-phase modulation leads to the overcompensated time synchronization between the orthogonally polarized components.

8.
Appl Opt ; 62(24): 6323-6332, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37706822

RESUMO

We have demonstrated a stable and low-noise all-polarization-maintaining (PM) ultrafast erbium-doped fiber laser mode-locked via nonlinear polarization evolution (NPE) in a linear cavity with dual outputs. A detailed design strategy is presented. The all-PM configuration enhances the capability of resistance to environmental fluctuations. Self-starting mode-locking is realized by using a non-reciprocal phase shifter. The dual-output structure offers the intracavity filtering effect, where the reflective port serves as a bandpass spectral filter, significantly improving the transmissive-port optical properties. The laser directly generates ultrashort pulses with a pulse duration of 129 fs operating at a fundamental repetition rate of 105.8 MHz. The integrated root-mean-square (RMS) relative intensity noise from 10 Hz to 10 MHz is ∼0.008%, and the integrated RMS timing jitter from 5 kHz to 10 MHz is ∼36f s. Long-term stability is confirmed in 25 h with a RMS power fluctuation of  ∼0.10%. Our high-performance fiber laser is a prospective candidate for low-noise applications.

9.
Appl Opt ; 62(22): 5946-5953, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706947

RESUMO

In mode-locked fiber lasers, the formation of ultrashort pulses from noisy or unstable states is a crucial area of research. Investigating these complex nonlinear dynamics can lead to valuable insights and new practical engineering techniques, particularly for the design and optimization of optical systems. Time-stretch dispersive Fourier transform, utilized in our study to investigate dissipative solitons formation in a net-normal dispersion nonlinear polarization evolution mode-locked fiber laser, provides a window into the intricate dynamics of such systems. In our experiments, the identification of five distinct transient stages in the formation process sheds light on the underlying mechanisms of dissipative soliton (DS) formation. The five distinct transient stages involved in the formation process include relaxation oscillation, modulation instability, spectral broadening, soliton explosions (SEs), and stable mode-locking. Notably, we also observed the generation of dissipative rogue waves during the SE stage. Our findings shed light on the intricate dynamics of DS formation and offer valuable insights for the design and optimization of mode-locked fiber lasers.

10.
ACS Appl Mater Interfaces ; 15(29): 35186-35195, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37449495

RESUMO

Epsilon-near-zero (ENZ) materials have attracted great interest due to their exotic linear and nonlinear responses, which makes it significant to tune ENZ wavelengths for wavelength-dependent applications. However, studies to achieve tunability in a wide spectral range and link the fabrication parameters with linear and nonlinear ENZ properties have been uncovered. ENZ indium tin oxide (ITO) nanofilms are fabricated by magnetron sputtering, through which the control of ENZ properties is demonstrated. Factors in the sputtering process, such as the gas ratio and annealing, have a great impact on the ITO samples. Tunable ENZ parameters are listed to provide a beneficial database for ENZ ITO, mainly attributed to the change of carrier concentration. The influence of ENZ parameters on optical characteristics via annealing treatment is further explored. The ENZ wavelength is blue-shifted by 609 nm, and the intrinsic loss is reduced by 63.2%, while the ITO samples exhibit better linear scattering properties and stronger field intensity enhancement. Additionally, the laser testing system illustrates the change from reverse saturable absorption to saturable absorption with an absolute modulation depth of 21.9%, improved by 222.1%, and the nonlinear refractive index n2 and nonlinear absorption coefficient ß are 2.07 × 10-16 m2 W-1 and -3.16 × 10-10 m W-1 for post-annealed ITO samples, respectively. The proposed sputtering protocol offers a feasible technique to control the linear and nonlinear ENZ performance, which has great potential in laser technology and nanophotonics.

11.
Front Nutr ; 9: 969848, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386900

RESUMO

Recent studies demonstrate that paternal nutrition prior to conception may determine offspring development and health through epigenetic modification. This study aims to investigate the effects of paternal supplementation of n-3 polyunsaturated fatty acids (n-3 PUFAs) on the brain development and function, and associated gene imprinting in the offspring. Three to four-week-old male C57BL/6J mice (founder) were fed with an n-3 PUFA-deficient diet (n-3 D), and two n-3 PUFA supplementation diets - a normal n-3 PUFA content diet (n-3 N) and a high n-3 PUFA content diet (n-3 H) for 12 weeks. Then they were mated to 10-week-old virgin female C57BL/6J mice to generate the offspring. The results showed that paternal n-3 PUFA supplementation in preconception reduced the anxiety- and depressive-like behavior, and improved sociability, learning and memory in the offspring, along with increased synaptic number, upregulated expressions of neuron specific enolase, myelin basic protein, glial fibrillary acidic protein, brain-derived neurotrophic factor in the hippocampus and cerebral cortex, and altered expressions of genes associated with mitochondria biogenesis, fusion, fission and autophagy. Furthermore, with paternal n-3 PUFA supplementation, the expression of imprinted gene Snrpn was downregulated both in testes of the founder mice and their offspring, but upregulated in the cerebral cortex and hippocampus, with altered DNA methylation in its differentially methylated region. The data suggest that higher paternal intake of n-3 PUFAs in preconception may help to maintain optimal brain development and function in the offspring, and further raise the possibility of paternal nutritional intervention for mental health issues in subsequent generations.

12.
Clin Exp Rheumatol ; 40(2): 443-449, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34251318

RESUMO

OBJECTIVES: Juvenile dermatomyositis (JDM) is an autoimmune disease characterised by a great heterogeneity in its clinical manifestations. In this study, we aimed to investigate the association between different clinical subtypes, laboratory data, and myositis antibodies of JDM. METHODS: A total of 132 JDM patients were enrolled and their medical records were retrospectively reviewed and autoantibodies tested. Twenty-one variables, including clinical manifestations and laboratory findings, were selected for analysis. We selected principal component analysis (PCA) as a pre-processing method for cluster analysis to convert the 21 original variables into independent principal components. We then conducted a PCA-based cluster analysis in order to analyse the association between patient clusters and the clinical data, laboratory data, and myositis autoantibodies. RESULTS: We identified 4 distinct JDM subgroups by PCA-based cluster analysis, namely: cluster A, JDM patients with arthralgia and intense inflammation; cluster B, JDM patients with clinical manifestations of vasculitis; cluster C, hypermyopathic JDM patients; and cluster D, JDM patients with skin involvement. There were significant differences between the 4 groups in serum alkaline phosphatase levels, usage of aggressive immunosuppressive therapy, and autoantibody expression of anti-mi2, anti-MDA5, anti-Jo1, and anti-PM-Scl100. CONCLUSIONS: We conducted cluster analysis of a cohort of JDM patients and identified 4 subgroups that represented diverse characteristics in the distribution of laboratory data and myositis autoantibodies, indicating that multidimensional assessment of clinical manifestations is highly valuable and urgently needed in JDM patients. These subgroups may contribute to individualised treatments and improved JDM patient prognosis.


Assuntos
Dermatomiosite , Miosite , Autoanticorpos , Análise por Conglomerados , Dermatomiosite/diagnóstico , Humanos , Miosite/diagnóstico , Análise de Componente Principal , Estudos Retrospectivos
13.
Front Nutr ; 9: 1043876, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36618698

RESUMO

Background: This study determined the effects of the paternal dietary ratio of n-6: n-3 polyunsaturated fatty acids (PUFAs) on leptin expression in the offspring and associated gene imprinting in a mouse model. Methods: Three- to four-week-old male C57BL/6J mice (F0) were fed an n-3 PUFA-deficient (n-3 D) diet, a diet with normal n-3 PUFA content (n-3 N; n-6: n-3 = 4.3:1), or a diet with a high n-3 PUFA content (n-3 H; n-6: n-3 = 1.5:1) for 8 weeks. Two subsequent generations were generated by mating F0 and F1 male mice with 10-week-old virgin female C57 BL/6J mice, to produce F1 and F2 offspring. Results: Compared to the paternal n-3 D diet, paternal n-3 N and n-3 H diets reduced adipose mRNA expression of leptin (Lep) and its plasma concentrations in juvenile F1 male and female offspring, and adult F1 male and F2 female offspring, with upregulated Lep receptor mRNA expression in the hypothalamus. Meanwhile, paternal n-3 N and n-3 H diets altered the expression of the imprinted genes H19, Igf2, Igf2r, Plagl1, Cdkn1c, Kcnq1ot1, Peg3, and Grb10 in the adipose tissue of juvenile and adult F1 males, with almost no effects on F1 females, while more effects were observed in the adult F2 females than F2 males. Principal component analysis verified that Plagl1, Cdkn1c, and Kcnq1ot1 contributed the most to variation in adipose tissue expression in all offspring. Some of these genes (Plagl1, Cdkn1c, Kcnq1ot1, Peg3, and Grb10) were altered by the paternal n-3 N and n-3 H diets in the F1 and F2 generation testes as well. Furthermore, adipose Lep expression was positively correlated with expressions of H19, Igf2r, Plagl1, and Kcnq1ot1 in juvenile F1 males and females, negatively correlated with the Kcnq1ot1 expression in adult F1 males, and positively correlated with the Plagl1 expression in adult F2 females. Conclusion: These data imply that paternal Plagl1, Cdkn1c, and Kcnq1ot1 might be part of the pathways involved in offspring leptin programming. Therefore, a lower ratio of n-6: n-3 PUFAs, with higher intake of n-3 PUFAs in paternal pre-conception, may help maintain the offspring's optimal leptin pattern in a sex-specific manner through multiple generations, and thereby, be beneficial for the offspring's long-term health.

14.
Front Immunol ; 13: 940802, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36703989

RESUMO

Objective: The anti-MDA5 (anti-melanoma differentiation associated gene 5) antibody is often associated with a poor prognosis in juvenile dermatomyositis (JDM) patients. In many developing countries, there is limited ability to access myositis- specific antibodies due to financial and technological issues, especially in remote regions. This study was performed to develop a prediction model for screening anti-MDA5 antibodies in JDM patients with commonly available clinical findings. Methods: A cross-sectional study was undertaken with 152 patients enrolled from the inpatient wards of Beijing Children's Hospital between June 2018 and September 2021. Stepwise logistic regression, least absolute shrinkage and selection operator (LASSO) regression, and the random forest (RF) method were used to fit the model. Model discrimination, calibration, and decision curve analysis were performed for validation. Results: The final prediction model included eight clinical variables (gender, fever, alopecia, periungual telangiectasia, digital ulcer, interstitial lung disease, arthritis/arthralgia, and Gottron sign) and four auxiliary results (WBC, CK, CKMB, and ALB). An anti-MDA5 antibody risk probability-predictive nomogram was established with an AUC of 0.975 predicted by the random forest algorithm. The model was internally validated by Harrell's concordance index (0.904), the Brier score (0.052), and a 500 bootstrapped satisfactory calibration curve. According to the net benefit and predicted probability thresholds of decision curve analysis, the established model showed a significantly higher net benefit than the traditional logistic regression model. Conclusion: We developed a prediction model using routine clinical assessments to screen for JDM patients likely to be anti-MDA5 positive. This new tool may effectively predict the detection of anti-MDA5 in these patients using a non-invasive and efficient way.


Assuntos
Dermatomiosite , Humanos , Criança , Estudos Transversais , Helicase IFIH1 Induzida por Interferon , Anticorpos , Aprendizado de Máquina , Fatores de Risco
15.
Sci Rep ; 11(1): 15936, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354198

RESUMO

We introduce supercritical fluid (SCF) technology to epsilon-near-zero (ENZ) photonics for the first time and experimentally demonstrate the manipulation of the ENZ wavelength for the enhancement of linear and nonlinear optical absorption in ENZ indium tin oxide (ITO) nanolayer. Inspired by the SCF's applications in repairing defects, reconnecting bonds, introducing dopants, and boosting the performance of microelectronic devices, here, this technique is used to exploit the influence of the electronic properties on optical characteristics. By reducing oxygen vacancies and electron scattering in the SCF oxidation process, the ENZ wavelength is shifted by 23.25 nm, the intrinsic loss is reduced by 20%, and the saturable absorption modulation depth is enhanced by > 30%. The proposed technique offers a time-saving low-temperature technique to optimize the linear and nonlinear absorption performance of plasmonics-based ENZ nanophotonic devices.

16.
Traffic Inj Prev ; 22(7): 542-546, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34410836

RESUMO

OBJECTIVE: The observation study sought to explore the influencing factors associated with mobile phone use when e-cyclists were waiting for red lights at intersections, which provided a theoretical foundation for solving the potential traffic threat and developing management plans for e-cyclists. METHODS: Data regarding e-cyclists were collected through camera conducted at the entrance of multiple intersections in Zhenjiang, China in July 2020. The data was reviewed by playing frame by frame. A statistical analysis was performed with the statistical package SPSS software. After conducting univariate logistic analysis on study variables, the multivariate analysis was adopted based on the binary logit regression model. RESULTS: Among the 1166 e-cyclists observed, 15.01% (n = 175) e-cyclists had operated their mobile phones while waiting for red lights. Young e-cyclists, delivery cyclists were more likely to be involved with mobile phone use. Furthermore, mobile phone use was more observed at intersections in suburban areas and with long waiting time. E-cyclists, who was carrying a child, rarely used mobile phone. All intersections during off-peak times showed an increase in mobile phone use. The results also show that neither e-cyclists themselves nor traffic managers are aware of the risks of mobile phone use and the impact on traffic safety while waiting for a red light. CONCLUSIONS: The findings of this research revealed the factors influencing mobile phone use of e-cyclists while waiting for a red light, and indicated that education and behavioral intervention need to be strengthened to improve riding safety at intersections. These results will be helpful in developing programs of electric bicycle management.


Assuntos
Uso do Telefone Celular , Telefone Celular , Acidentes de Trânsito , Ciclismo , China , Humanos , Modelos Logísticos
17.
Opt Express ; 29(2): 1090-1101, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33726331

RESUMO

A novel fiber Michelson interferometer (FMI) based on parallel dual polarization maintaining fiber Sagnac interferometers (PMF-SIs) is proposed and experimentally demonstrated for temperature sensing. The free spectral range (FSR) difference of dual PMF-SIs determines the FSR of envelope and sensitivity of the sensor. The temperature sensitivity of parallel dual PMF-SIs is greatly enhanced by the Vernier effect. Experimental results show that the temperature sensitivity of the proposed sensor is improved from -1.646 nm/°C (single PMF-SI) to 78.984 nm/°C (parallel dual PMF-SIs), with a magnification factor of 47.99, and the temperature resolution is improved from ±0.03037°C to ±0.00063°C by optimizing the FSR difference between the two PMF-SIs. Our proposed ultrasensitive temperature sensor is with easy fabrication, low cost and simple configuration which can be implemented for various real applications that need high precision temperature measurement.

18.
BMC Pediatr ; 21(1): 24, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413203

RESUMO

BACKGROUND: Telomeres play a crucial role in cellular survival and its length is a predictor for onset of chronic non-communicable diseases. Studies on association between telomeres and obesity in children have brought discrepant results and the underlying mechanisms and influential factors are to be elucidated. This study aimed to investigate changes in telomere length and telomerase reverse transcriptase (TERT) DNA methylation, and further to determine their correlation with n-3 polyunsaturated fatty acids (PUFAs) in preschool children with obesity. METHODS: Forty-six preschool children with obesity aged 3 to 4 years were included in the study, with equal numbers of age- and gender-matched children with normal weight as control. Leukocyte telomere length was determined by the ratio of telomeric product and single copy gene obtained using real-time qPCR. DNA methylation of TERT promoter was analyzed by bisulfite sequencing. Fatty acids in erythrocytes were measured by gas chromatography with a total of 15 fatty acids analyzed. The total saturated fatty acids (SFAs), total n-6 PUFAs, total n-3 PUFAs, and the ratio of arachidonic acid (AA) to docosahexaenoic acid (DHA) were calculated. Then the correlation between leukocyte telomere length, TERT promoter methylation and fatty acids was determined. RESULTS: In preschool children with obesity, leukocyte telomeres were shortened and had a negative association with the body mass index. The methylated fractions in 13 of 25 CpG sites in the TERT promoter were increased by approximately 3 to 35% in the children with obesity compared to the normal weight children. Erythrocyte lauric acid and total SFAs, lenoleic acid and total n-6 PUFAs were higher, and DHA was lower in the children with obesity than those in the children with normal weight. Correlative analysis showed that leukocyte telomere length had a positive association with total SFAs and DHA, and a negative association with the AA/DHA ratio. However, no association between erythrocyte DHA and the TERT promoter methylation was found. CONCLUSION: These data indicate that the reduced body DHA content and increased AA/DHA ratio may be associated with shortened leukocyte telomeres in child obesity, which is probably not involved in the TERT promoter methylation.


Assuntos
Ácidos Graxos Ômega-3 , Obesidade Infantil , Telomerase , Pré-Escolar , Metilação de DNA , Humanos , Obesidade Infantil/genética , Telomerase/genética , Telomerase/metabolismo , Telômero/genética , Telômero/metabolismo
19.
Front Nutr ; 8: 779306, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35155512

RESUMO

Few studies have investigated the correlation between maternal polyunsaturated fatty acids (PUFAs) and telomeres in offspring, and the underlying influential mechanisms. In this study, we assessed the associations of maternal PUFAs with telomere length (TL) and DNA methylation of the telomerase reverse transcriptase (TERT) promoter in the cord blood and the placenta. A total of 274 pregnant women and their newborn babies were enrolled in this study. Maternal blood before delivery, the cord blood, and the placenta at birth were collected. Fatty acids in maternal erythrocytes and cord blood cells were measured by gas chromatography (GC). TL in the cord blood and the placenta was determined using real-time quantitative PCR (qPCR) by calculating the product ratio of telomeric DNA to the single-copy gene ß-globin. The TERT promoter methylation was analyzed by DNA bisulfite sequencing. The associations of maternal fatty acids with TL were analyzed by univariate and multivariate regression. We found that low concentrations of docosapentaenoci acid (DPA, C22: 5n-3) and total n-3 PUFAs, adrenic acid (ADA, C22: 4n-6), and osbond acid (OA, C22: 5n-6) and high concentrations of linoleic acid (LA, C18: 2n-6) in maternal erythrocytes were associated with the shortened TL in cord blood cells (estimated difference in univariate analysis -0.36 to -0.46 for extreme quintile compared with middle quintile), and that low concentrations of cord blood docosahexaenoic acid (DHA, C22: 6n-3) were related to the shortened TL in cord blood cells. Differently, high concentrations of α-linolenic acid (LNA, C18: 3n-3), eicosatrienoic acid (EA, C20: 3n-3), DHA, and γ-linoleic acid (GLA, C18:3n-6) in maternal erythrocytes were associated with the shortened TL in the placenta (estimated difference in univariate analysis -0.36 to -0.45 for higher quintiles compared with the middle quintile). Further examination demonstrated that the concentrations of DHA and total n-3 PUFAs in maternal erythrocytes had positive associations with DNA methylation of the TERT promoter in the cord blood instead of the placenta. These data suggest that maternal PUFAs are closely correlated to infant TL and the TERT promoter methylation, which are differently affected by maternal n-3 PUFAs between the cord blood and the placenta. Therefore, keeping higher levels of maternal n-3 PUFAs during pregnancy may help to maintain TL in the offspring, which is beneficial to long-term health.

20.
Front Nutr ; 7: 589771, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33330591

RESUMO

Quantitative PCR (qPCR), the most accurate and sensitive technique for quantifying mRNA expression, and choice of appropriate reference genes for internal error controlling in qPCR are essential to understanding the molecular mechanisms that drive the obesity epidemic and its comorbidities. In this study, using the high-fat diet (HFD)-induced obese mouse model, we assessed the expression of 10 commonly used reference genes to validate gene-expression stability in adipose tissue, liver, and muscle across different time points (4, 8, 12, and 16 weeks after HFD feeding) during the process of obesity. The data were analyzed by the GeNorm, NormFinder, BestKeeper, and Delta-Ct method, and the results showed that the most stable reference genes were different for a specific organ or tissue in a specific time point; however, PPIA, RPLP0, and YWHAZ were the top three most stable reference genes in qPCR experiments on adipose, hepatic tissues, and muscles of mice in diet-induced obesity. In addition, the mostly used genes ACTB and GAPDH were more unstable in the fat and liver, the ACTB mRNA levels were increased in four adipose tissues, and the GAPDH mRNA levels were decreased in four adipose tissues and liver after HFD feeding. These results suggest that PPIA, RPLP0, or YWHAZ may be more appropriate to be used as reference gene than ACTB and GAPDH in the adipose tissue and liver of mice during the process of high-fat diet-induced obesity.

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