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BACKGROUND: To develop a deep learning(DL) model utilizing ultrasound images, and evaluate its efficacy in distinguishing between benign and malignant parotid tumors (PTs), as well as its practicality in assisting clinicians with accurate diagnosis. METHODS: A total of 2211 ultrasound images of 980 pathologically confirmed PTs (Training set: n = 721; Validation set: n = 82; Internal-test set: n = 89; External-test set: n = 88) from 907 patients were retrospectively included in this study. The optimal model was selected and the diagnostic performance evaluation is conducted by utilizing the area under curve (AUC) of the receiver-operating characteristic(ROC) based on five different DL networks constructed at varying depths. Furthermore, a comparison of different seniority radiologists was made in the presence of the optimal auxiliary diagnosis model. Additionally, the diagnostic confusion matrix of the optimal model was calculated, and an analysis and summary of misjudged cases' characteristics were conducted. RESULTS: The Resnet18 demonstrated superior diagnostic performance, with an AUC value of 0.947, accuracy of 88.5%, sensitivity of 78.2%, and specificity of 92.7% in internal-test set, and with an AUC value of 0.925, accuracy of 89.8%, sensitivity of 83.3%, and specificity of 90.6% in external-test set. The PTs were subjectively assessed twice by six radiologists, both with and without the assisted of the model. With the assisted of the model, both junior and senior radiologists demonstrated enhanced diagnostic performance. In the internal-test set, there was an increase in AUC values by 0.062 and 0.082 for junior radiologists respectively, while senior radiologists experienced an improvement of 0.066 and 0.106 in their respective AUC values. CONCLUSIONS: The DL model based on ultrasound images demonstrates exceptional capability in distinguishing between benign and malignant PTs, thereby assisting radiologists of varying expertise levels to achieve heightened diagnostic performance, and serve as a noninvasive imaging adjunct diagnostic method for clinical purposes.
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Aprendizado Profundo , Neoplasias Parotídeas , Ultrassonografia , Humanos , Estudos Retrospectivos , Ultrassonografia/métodos , Neoplasias Parotídeas/diagnóstico por imagem , Neoplasias Parotídeas/patologia , Neoplasias Parotídeas/diagnóstico , Masculino , Pessoa de Meia-Idade , Feminino , Adulto , Idoso , Adulto Jovem , Curva ROC , Diagnóstico Diferencial , Adolescente , Idoso de 80 Anos ou mais , Sensibilidade e Especificidade , CriançaRESUMO
OBJECTIVES: This study aimed to propose a deep learning (DL)-based framework for identifying the composition of thyroid nodules and assessing their malignancy risk. METHODS: We conducted a retrospective multicenter study using ultrasound images from four hospitals. Convolutional neural network (CNN) models were constructed to classify ultrasound images of thyroid nodules into solid and non-solid, as well as benign and malignant. A total of 11,201 images of 6784 nodules were used for training, validation, and testing. The area under the receiver-operating characteristic curve (AUC) was employed as the primary evaluation index. RESULTS: The models had AUCs higher than 0.91 in the benign and malignant grading of solid thyroid nodules, with the Inception-ResNet AUC being the highest at 0.94. In the test set, the best algorithm for identifying benign and malignant thyroid nodules had a sensitivity of 0.88, and a specificity of 0.86. In the human vs. DL test set, the best algorithm had a sensitivity of 0.93, and a specificity of 0.86. The Inception-ResNet model performed better than the senior physicians (p < 0.001). The sensitivity and specificity of the optimal model based on the external test set were 0.90 and 0.75, respectively. CONCLUSIONS: This research demonstrates that CNNs can assist thyroid nodule diagnosis and reduce the rate of unnecessary fine-needle aspiration (FNA). CLINICAL RELEVANCE STATEMENT: High-resolution ultrasound has led to increased detection of thyroid nodules. This results in unnecessary fine-needle aspiration and anxiety for patients whose nodules are benign. Deep learning can solve these problems to some extent. KEY POINTS: ⢠Thyroid solid nodules have a high probability of malignancy. ⢠Our models can improve the differentiation between benign and malignant solid thyroid nodules. ⢠The differential performance of one model was superior to that of senior radiologists. Applying this could reduce the rate of unnecessary fine-needle aspiration of solid thyroid nodules.
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Aprendizado Profundo , Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Diagnóstico Diferencial , Sensibilidade e Especificidade , Ultrassonografia/métodos , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologiaRESUMO
BACKGROUND: The global prospective surveillance data showed the re-emergence of mycoplasma pneumoniae pneumonia (MPP) in Europe and Asia after the coronavirus disease 2019 pandemic. We sought to observe the effect of macrolide antibiotics in the treatment of MPP carrying a macrolide-resistant mutation gene and the potential of targeted next-generation sequencing (tNGS) as a front-line diagnostic in MPP patients. METHODS: The baseline characteristics of 91 children with MPP hospitalized from January to October 2023 were retrospectively analyzed. They were divided into two groups according to whether carrying the macrolide-resistant mutation or not. The logistic and linear regression analyses were used to determine whether the mutation was a standalone predictive predictor of the duration of fever and hospital length of stay. RESULTS: First, no patients had a fever for ≥ 7 days after macrolide treatment. But length of stay and hormone concentration were significantly different between the two groups (P < 0.05). There were also no statistical association between the mutation and the duration of fever and hospital length of stay. CONCLUSION: Macrolides can be administered to MPP children carrying a macrolide-resistant mutation. tNGS can be seen as a front-line diagnostic in MPP.
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Antibacterianos , Farmacorresistência Bacteriana , Macrolídeos , Mutação , Mycoplasma pneumoniae , Pneumonia por Mycoplasma , RNA Ribossômico 23S , Humanos , Pneumonia por Mycoplasma/tratamento farmacológico , Pneumonia por Mycoplasma/microbiologia , Macrolídeos/uso terapêutico , Macrolídeos/farmacologia , Mycoplasma pneumoniae/genética , Mycoplasma pneumoniae/efeitos dos fármacos , Feminino , Masculino , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Pré-Escolar , Criança , Farmacorresistência Bacteriana/genética , Estudos Retrospectivos , RNA Ribossômico 23S/genética , Lactente , Tempo de Internação , Resultado do Tratamento , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
BACKGROUND: The objective of this study was to develop a model combining ultrasound (US) and clinicopathological characteristics to predict the pathologic response to neoadjuvant chemotherapy (NACT) in human epidermal growth factor receptor 2 (HER2)-positive breast cancer. MATERIALS AND METHODS: This is a retrospective study that included 248 patients with HER2-positive breast cancer who underwent NACT from March 2018 to March 2022. US and clinicopathological characteristics were collected from all patients in this study, and characteristics obtained using univariate analysis at p < 0.1 were subjected to multivariate analysis and then the conventional US and clinicopathological characteristics independently associated with pathologic complete response (pCR) from the analysis were used to develop US models, clinicopathological models, and their combined models by the area under the receiver operating characteristic (ROC) curve (AUC), accuracy, sensitivity, and specificity to assess their predictive efficacy. RESULTS: The combined model had an AUC of 0.808, a sensitivity of 88.72%, a specificity of 60.87%, and an accuracy of 75.81% in predicting pCR of HER2-positive breast cancer after NACT, which was significantly better than the clinicopathological model (AUC = 0.656) and the US model (AUC = 0.769). In addition, six characteristics were screened as independent predictors, namely the Clinical T stage, Clinical N stage, PR status, posterior acoustic, margin, and calcification. CONCLUSION: The conventional US combined with clinicopathological characteristics to construct a combined model has a good diagnostic effect in predicting pCR in HER2-positive breast cancer and is expected to be a useful tool to assist clinicians in effectively determining the efficacy of NACT in HER2-positive breast cancer patients.
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Neoplasias da Mama , Terapia Neoadjuvante , Humanos , Feminino , Estudos de Casos e Controles , Estudos Retrospectivos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , UltrassonografiaRESUMO
Porcine reproductive and respiratory syndrome virus (PRRSV) is a highly infectious and pathogenic agent that causes considerable economic damage in the swine industry. It regulates the inflammatory response, triggers inflammation-induced tissue damage, suppresses the innate immune response, and leads to persistent infection. Interleukin-8 (IL-8), a pro-inflammatory chemokine, plays a crucial role in inflammatory response during numerous bacteria and virus infections. However, the underlying mechanisms of IL-8 regulation during PRRSV infection are not well understood. In this study, we demonstrate that PRRSV-infected PAMs and Marc-145 cells release higher levels of IL-8. We screened the nucleocapsid protein, non-structural protein (nsp) 9, and nsp11 of PRRSV to enhance IL-8 promoter activity via the C/EBPα pathway. Furthermore, we identified that the amino acids Q35A, S36A, R113A, and I115A of the nucleocapsid protein play a crucial role in the induction of IL-8. Through reverse genetics, we generated two mutant viruses (rQ35-2A and rR113A), which showed lower induction of IL-8 in PAMs during infection. This finding uncovers a previously unrecognized role of the PRRSV nucleocapsid protein in modulating IL-8 production and provides insight into an additional mechanism by which PRRSV modulates immune responses and inflammation.
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Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Animais , Suínos , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , Interleucina-8/genética , Proteínas do Nucleocapsídeo/genética , Proteínas do Nucleocapsídeo/metabolismo , Inflamação , Macrófagos Alveolares/metabolismoRESUMO
Employing functional and structured thin films on fiber optic sensors has tremendously improved capabilities in humidity sensing applications. In this paper, we demonstrate fabrication of a fiber optic evanescent wave humidity sensor based on S i O 2/porous polymethyl methacrylate (PMMA) thin films. With the exposure to moisture, S i O 2/porous PMMA thin films absorb water molecules. The refractive index and absorption coefficient of thin films change with ambient humidity, resulting in modulation of the light intensity transmitted in fiber. A good linearity is determined between the logarithm of output light intensity and relative humidity (RH). An optimal average sensitivity of 188.3 lux/%RH is achieved with an increase of 11.7 fold in the RH range of 5% to 95%. The response and recovery times are 8 s and 23 s, respectively. Furthermore, the sensor exhibits low hysteresis, and excellent stability and repeatability.
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MiR-424-5p was found to be a potential regulator in the proliferation, migration, and invasion of various cancer cells. However, the effects and functional mechanism of miR-424-5p in the process of myogenesis are still unclear. Previously, using microRNA (miRNA) sequencing and expression analysis, we discovered that miR-424-5p was expressed differentially in the different skeletal muscle growth periods of Xuhuai goats. We hypothesized that miR-424-5p might play an important role in skeletal muscle myogenesis. Then, we found that the proliferation ability of the mouse myoblast cell (C2C12 myoblast cell line) was significantly augmented, whereas the C2C12 differentiation was repressed after increasing the expression of miR-424-5p. Mechanistically, HSP90AA1 presented a close interrelation with miR-424-5p, which was predicted as a target gene in the progression of skeletal muscle myogenesis, using transcriptome sequencing, dual luciferase reporter gene detection, and qRT-PCR. The silencing of HSP90AA1 obviously increased C2C12 proliferation and diminished differentiation, which is consistent with the ability of miR-424-5p in C2C12. Altogether, our findings indicated the role of miR-424-5p as a novel potential regulator via HSP90AA1 during muscle myogenesis progression.
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MicroRNAs , Animais , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células/genética , Diferenciação Celular/genética , Linhagem Celular , Desenvolvimento Muscular/genética , Cabras/genética , Músculo Esquelético/metabolismoRESUMO
BACKGROUND: Spinal cord stimulation (SCS) has been suggested as a treatment option to improve the quality-adjusted life years of individuals with low back pain. However, previous reviews have some methodologic limitations. This review aims to evaluate the effectiveness of novel SCS waveforms on pain outcomes in patients with low back pain (LBP) compared with traditional SCS or placebo comparator. MATERIALS AND METHODS: Nine electronic data bases, ongoing trials, gray literature, and targeted journals were searched from inception to December 27, 2021. The Cochrane risk of bias and Grading of Recommendation, Assessment, Development, and Evaluations were used to appraise individual and overall evidence. Subjects aged ≥ 18 years with or without previous surgeries and having LBP for at least three months were included. The primary outcome was pain intensity including back or leg pain scores at postintervention. Secondary outcomes comprised decrease in back, leg, and overall pain, and health-related quality of life. RESULTS: A total of 11 randomized controlled trials (RCTs) involving 955 participants across four countries were included. Our meta-analysis revealed that novel SCS waveform was superior to traditional SCS or placebo comparator for treating leg pain (Z = -2.12, p = 0.03) with a small effect size (Hedges' g = -0.18, 95% CI: -0.34 to -0.01). Back-pain intensity (g = -0.22, 95% CI: -0.47 to 0.02) and health-related quality of life (g = -0.12, 95% CI: -0.43 to 0.18) were similar between the novel SCS waveform group and the traditional SCS or placebo comparator groups. The meta-regression did not identify any effect of the covariates on back-pain intensity. CONCLUSIONS: With low certainty of evidence, this finding provides a rationale for considering the novel SCS waveform as complements to the usual therapeutic plan. Future trials should adopt well-designed RCTs with larger sample size and follow-up assessment.
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Dor Crônica , Dor Lombar , Estimulação da Medula Espinal , Humanos , Dor Lombar/terapia , Perna (Membro) , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição da Dor , Dor Crônica/terapiaRESUMO
The aims of the review were to (i) evaluate the effectiveness of wearable-delivered sleep interventions on sleep outcomes among adults, and (ii) explore the effect of factors affecting total sleep time. Eight databases were searched to identify relevant studies in English from inception until December 23, 2021. The Cochrane Risk of Bias tool version 2.0 and Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) criteria were used to assess the risk of bias and certainty of the evidence, respectively. Twenty randomized controlled trials (RCTs) were included, involving 1608 adults across nine countries. Wearable-delivered sleep interventions elicited significant improvement of 1.96 events/h for the oxygen desaturation index and 3.13 events/h for the respiratory distress index. Meta-analyses found that wearable-delivered sleep interventions significantly decreased sleep disturbance (Hedges' g [g] = -0.37, 95% confidence interval [CI]: -0.59, -0.15) and sleep-related impairment (g = -1.06, 95% CI: -1.99, -0.13) versus the comparators. The wearable-delivered sleep interventions may complement usual care to improve sleep outcomes. More rigorous RCTs with a long-term assessment in a wide range of populations are warranted.
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Sono , Dispositivos Eletrônicos Vestíveis , Humanos , Adulto , Ensaios Clínicos Controlados Aleatórios como Assunto , Duração do SonoRESUMO
A fiber optic humidity sensor based on polyvinyl alcohol (PVA)/Tween 20 film has been fabricated by modulating the intensity of light transmitted in optical fiber. PVA/Tween 20 film was used as the cladding and humidity-sensitive material of optical fiber. The logarithmic of output light intensity exhibited a linear increase with the increase of humidity (22%-82%RH). With the addition of Tween 20 in the formation of film, average sensitivity increased by 13-fold. Fast equilibrium on adsorption and desorption of water molecules were also achieved on the film. The response and recovery times were determined to be 11 s and 9 s, respectively. Moreover, the sensor possesses good repeatability. The sensing mechanism was probably based on the swelling of PVA after adsorbing water molecules, which affected scattering of evanescent waves in the cladding. The output light intensity varied with the decay of evanescent waves.
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AMPK plays an important role in regulating the metabolism of carbohydrate, lipid and protein in an organism, and is considered to be a key regulator of cellular energy homeostasis. In recent years, attention has been drawn to AMPK subunit polymorphisms and their association with economical traits of domestic animals and fowls. PRKAB1 encodes the ß1 regulatory subunit of AMPK, and it has been reported that PRKAB1 may be applied in breeding programs of meat-type chicken. To date, the polymorphism of goat PRKAB1 gene and its associations remain unknown. In this paper, the polymorphism of PRKAB1 gene was detected in 316 goats of three breeds. A total of four novel single nucleotide polymorphisms (SNPs) of PRKAB1 gene were revealed by sequence analysis. Among them, three were in the coding region (285 C > A, 297 C > A, 309 C > T), and they were all synonymous. One was in the intron (229 A > G). The associations between polymorphic loci and the growth traits of Xuhuai and Haimen goats were analyzed, and significant associations were found in body length index and trunk index (p < 0.05) for Xuhuai breed, while no significant associations in Haimen breed. Our results provide useful information for the improvement and breeding of Chinese native goats.
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Cabras , Polimorfismo de Nucleotídeo Único , Animais , Polimorfismo de Nucleotídeo Único/genética , Cabras/fisiologia , Proteínas Quinases Ativadas por AMP/genética , FenótipoRESUMO
Kynurenine 3-monooxygenase (KMO) is the pivotal enzyme in the kynurenine pathway and is located on the mitochondrial outer membrane. The dysregulation of KMO leads to various neurodegenerative diseases; however, it is rarely mentioned in cancer progression. Our previous study showed that KMO overexpression in canine mammary gland tumors (cMGT) is associated with poor prognosis in cMGT patients. Surprisingly, it was also found that KMO can be located on the cell membranes of cMGT cells, unlike its location in normal cells, where KMO is expressed only within the cytosol. Since cMGT and human breast cancer share similar morphologies and pathogenesis, this study investigated the possibility of detecting surface KMO in human breast cancers and the role of surface KMO in tumorigenesis. Using immunohistochemistry (IHC), flow cytometry (FC), immunofluorescence assay (IFA), and transmission electron microscopy (TEM), we demonstrated that KMO can be aberrantly and highly expressed on the cell membranes of breast cancer tissues and in an array of cell lines. Masking surface KMO with anti-KMO antibody reduced the cell viability and inhibited the migration and invasion of the triple-negative breast cancer cell line, MDA-MB-231. These results indicated that aberrant surface expression of KMO may be a potential therapeutic target for human breast cancers.
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Quinurenina 3-Mono-Oxigenase/biossíntese , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/secundário , Proliferação de Células , Humanos , Quinurenina 3-Mono-Oxigenase/análise , Neoplasias de Mama Triplo Negativas/química , Neoplasias de Mama Triplo Negativas/patologia , Células Tumorais CultivadasRESUMO
PURPOSE: The existing concept suggests early palliative and hospice therapy for a better quality of care (QOC) and less medical expense in terminal cancer patients, but the time points of "early" initiation were defined by pre-set study protocol rather than the real-world data. The study aimed to determine the optimal timing of initiating palliative care for patients with terminal cancer. METHODS: This retrospective population-based study was conducted using a nationwide database. We extracted patients with cancer who were in their last year of lives in the period from 1 January 2010 to 31 December 2013 and categorized them into two groups ("hospice-shared care" (HSC) group and "usual care" (UC) group) after a matching process. Subsequently, we used a generalized linear mixed-effects model to compare the QOC and medical expenses between groups. RESULTS: After the selection and matching process, we enrolled 1714 patients (67.7 ± 13.2 years, 62.7% male) categorized into the HSC and UC groups (n = 857 in each group). The HSC groups showed generally better QOC in the four indices (with emergency room visit, hospitalization, intensive care unit admission, and receiving chemotherapy) than the UC group in those who initiated HSC 8-60 days before death. The HSC group also had significantly lower medical expenses than the UC group in those who initiated HSC 15-90 days before death. CONCLUSIONS: Among patients with terminal cancer, HSC initiation before the last 8 days and 15 days of lives can effectively improve QOC and save medical expenses, respectively.
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Cuidados Paliativos na Terminalidade da Vida , Hospitais para Doentes Terminais , Neoplasias , Assistência Terminal , Feminino , Humanos , Masculino , Neoplasias/terapia , Cuidados Paliativos , Estudos RetrospectivosRESUMO
A SiO2/TiO2 bilayer thin-film-based fiber optic humidity sensor was fabricated via a modified dip coating process with enhanced sensitivity. SiO2 film was coated on the surface of the fiber core, followed by deposition of the TiO2 layer on SiO2. The relative humidity (RH) is measured by modulation in intensity of the transmitted laser at room temperature. The optical fiber humidity sensor based on SiO2/TiO2 film shows two-segmented linearity in measurement with sensitivities of 5.35 and 1.94 µW/% RH at 15%-50% RH and 50%-95% RH, respectively. The response time and recovery time are 25 s and 50 s, respectively. To our knowledge, the superior response time and recovery time of the sensor in our study were achieved over those fiber optic humidity sensors reported with modulation in intensity. Furthermore, this fiber optic humidity sensor has a good reproducibility and long-term stability. The sensing mechanism is attributed to effects of moisture on the refractive index and the light absorption coefficient of SiO2 film and modulation in the transmission characteristic of evanescent waves in the optical fiber.
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BACKGROUND AND OBJECTIVES: Laser is being widely used in clinical treatment nowadays, including 755 nm Alexandrite laser [1,2]. This study was conducted to examine the clinical outcome of long-pulse 755 nm Alexandrite laser in the treatment of venous lake of the lip. STUDY DESIGN/MATERIALS AND METHODS: Forty-one patients (2015-2019) were reviewed. The clinical outcomes were assessed 1 month after the treatment. The efficacy of the treatment was classified into four categories: basic recovery (most optimal outcome), effective, improvement, and ineffective (least favorable outcome). Adverse reactions were also recorded. RESULTS: Thirty-three (80.49%) patients achieved basic recovery and 8 (19.51%) were effective; 29 (70.73%) recovered after receiving one treatment, 3 (7.32%) recovered after receiving two treatments, and 1 (2.44%) recovered after three treatments. CONCLUSION: Long-pulse 755 nm Alexandrite laser is an effective treatment for the venous lake of the lip. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.
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Remoção de Cabelo , Lasers de Estado Sólido , Terapia com Luz de Baixa Intensidade , Humanos , Lasers de Estado Sólido/uso terapêutico , Lábio/cirurgia , Resultado do TratamentoRESUMO
OBJECTIVES: Understanding the molecular mechanisms of lipid synthesis in the mammary gland is crucial for regulating the level and composition of lipids in milk. This study aimed to investigate the functional and molecular mechanisms of miR-204-5p in mammary epithelial cells to provide a theoretical basis for milk lipid synthesis. METHODS: Real-time quantitative PCR was performed to detect the transcriptional levels of miR-204-5p and related mRNA abundance in mammary epithelial cells. Western blotting was conducted to determine protein expression. Cell proliferation was assessed by Cell Counting Kit-8. A dual-luciferase reporter assay was conducted to verify the targeting relationship between miR-204-5p and SIRT1. siRNA and overexpression plasmids were transfected into mouse HC11 mammary epithelial cells. RESULTS: The abundance of miR-204-5p was much higher in lactating mouse mammary glands than in other tissues, which indicated that miR-204-5p may be involved in regulating milk production. MiR-204-5p affected the expression of ß-casein and milk lipid synthesis in HC11 mouse mammary epithelial cells but did not influence the proliferation of HC11 cells. Overexpression of miR-204-5p signiï¬cantly increased the number of Oil Red O+ cells, triglyceride accumulation and the expression of markers associated with lipid synthesis, including FASN and PPARγ, whereas inhibition of miR-204-5p had the opposite effect. miR-204-5p promotes lipid synthesis by negatively regulating SIRT1. Overexpression of SIRT1 can repress the promotion of miR-204-5p on lipid synthesis. CONCLUSION: Our ï¬ndings showed that miR-204-5p can promote the synthesis of milk lipids in mammary epithelial cells by targeting SIRT1.
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Lipídeos/biossíntese , Glândulas Mamárias Animais/metabolismo , MicroRNAs/genética , Sirtuína 1/genética , Regiões 3' não Traduzidas , Animais , Sequência de Bases , Caseínas/biossíntese , Linhagem Celular , Células Epiteliais/metabolismo , Feminino , Expressão Gênica , Lactação/genética , Lactação/metabolismo , Glândulas Mamárias Animais/citologia , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Leite/metabolismo , Gravidez , RNA Interferente Pequeno/genética , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/metabolismo , Distribuição TecidualRESUMO
An ultra-smooth $\text{TiO}_2$TiO2 thin film based optical humidity sensor was fabricated via a modified dip coating process. The $\text{TiO}_2$TiO2 film possessed a root mean square roughness of ${2.6 \pm 0.3}\;\text{nm}$2.6±0.3nm. Measurement of relative humidity (RH) was performed by modulation in the intensity of laser transmitted at room temperature. The optical humidity sensor based on $\text{TiO}_2$TiO2 film exhibited two-segmented linearity in the whole RH range. The response time and recovery time were determined to be 27 s and 23 s, respectively. To our knowledge, the optical humidity sensor achieved the fastest recovery to date among those modulated in optical power. The fast response and recovery are attributed to the smooth surface of sensing film, which allows the rapid equilibrium between adsorption and desorption of water molecules on the film surface. In addition, this optical humidity sensor possessed an excellent reproducibility and long-term stability after aging. The sensing mechanism is based on the chemisorption of water molecules in the low RH range and formation of water droplets in the high RH range on the surface of ${\text{TiO}_2}$TiO2 film.
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A polarization-insensitive and angle-independent graphene absorber (GA) with periodically patterned grating is demonstrated. A periodic nanocavity composed of multilayer subwavelength grating and metal substrate supports a strongly localized mode inside the cavity, where the mode helps to absorb more electromagnetic waves. The proposed GA exhibits polarization-insensitive behavior and maintains the high absorption above 90% within a wide range of incident angle (more than 80°). We attribute the high absorption to the excitation of the cavity mode resonance and magnetic resonance for the transverse electric and transverse magnetic polarizations, respectively. The proposed GA has potential applications in the design of various devices, such as optical modulators or tunable absorption filters because of its remarkable angle-insensitive absorption performance.
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Correction for 'Recent advances in understanding of the mechanism and control of Li2O2 formation in aprotic Li-O2 batteries' by Zhiyang Lyu et al., Chem. Soc. Rev., 2017, DOI: 10.1039/c7cs00255f.
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Aprotic Li-O2 batteries represent promising alternative devices for electrical energy storage owing to their extremely high energy densities. Upon discharge, insulating solid Li2O2 forms on cathode surfaces, which is usually governed by two growth models, namely the solution model and the surface model. These Li2O2 growth models can largely determine the battery performances such as the discharge capacity, round-trip efficiency and cycling stability. Understanding the Li2O2 formation mechanism and controlling its growth are essential to fully realize the technological potential of Li-O2 batteries. In this review, we overview the recent advances in understanding the electrochemical and chemical processes that occur during the Li2O2 formation. In the beginning, the oxygen reduction mechanisms, the identification of O2-/LiO2 intermediates, and their influence on the Li2O2 morphology have been discussed. The effects of the discharge current density and potential on the Li2O2 growth model have been subsequently reviewed. Special focus is then given to the prominent strategies, including the electrolyte-mediated strategy and the cathode-catalyst-tailoring strategy, for controlling the Li2O2 growth pathways. Finally, we conclude by discussing the profound implications of controlling Li2O2 formation for further development in Li-O2 batteries.