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1.
Sensors (Basel) ; 24(14)2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-39065844

RESUMEN

The bird's-eye view (BEV) method, which is a vision-centric representation-based perception task, is essential and promising for future Autonomous Vehicle perception. It has advantages of fusion-friendly, intuitive, end-to-end optimization and is cheaper than LiDAR. The performance of existing BEV methods, however, would be deteriorated under the situation of a tire blow-out. This is because they quite rely on accurate camera calibration which may be disabled by noisy camera parameters during blow-out. Therefore, it is extremely unsafe to use existing BEV methods in the tire blow-out situation. In this paper, we propose a geometry-guided auto-resizable kernel transformer (GARKT) method, which is designed especially for vehicles with tire blow-out. Specifically, we establish a camera deviation model for vehicles with tire blow-out. Then we use the geometric priors to attain the prior position in perspective view with auto-resizable kernels. The resizable perception areas are encoded and flattened to generate BEV representation. GARKT predicts the nuScenes detection score (NDS) with a value of 0.439 on a newly created blow-out dataset based on nuScenes. NDS can still obtain 0.431 when the tire is completely flat, which is much more robust compared to other transformer-based BEV methods. Moreover, the GARKT method has almost real-time computing speed, with about 20.5 fps on one GPU.

2.
Opt Express ; 31(11): 18346-18355, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37381547

RESUMEN

We report a photonic approach to generate background-free multi-format dual-band microwave signals based on a single modulator, which is suitable for high-precision and fast detection of radars in complex electromagnetic environments. By applying different radio-frequency signals and electrical coding signals to the polarization-division multiplexing Mach-Zehnder modulator (PDM-MZM), the generation of dual-band dual-chirp signals or dual-band phase-coded pulse signals centered at 10 and 15.5 GHz is experimentally demonstrated. Furthermore, by choosing an appropriate fiber length, we verified that the generated dual-band dual-chirp signals are not affected by chromatic-dispersion induced-power fading (CDIP); meanwhile, by autocorrelation calculations, we got high pulse compression ratios (PCRs) of 13 of the generated dual-band phase-encoded signals, showing that the generated phase-encoded signals can be emitted directly without extra pulse truncation operation. The proposed system features a compact structure, reconfigurability and polarization independence, which is promising for multi-functional dual-band radar systems.

3.
Opt Express ; 30(17): 30149-30163, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36242124

RESUMEN

A photonic-assisted frequency downconverter with self-interference cancellation and fiber dispersion elimination is proposed for in-band full-duplex (IBFD) radio-over-fiber (ROF) systems based on stimulated Brillouin scattering. In this work, a dual-polarization Mach-Zehnder modulator (DPol-MZM) is employed to cancel the self-interference signal in the optical domain, thus the proposed system has a large operation bandwidth without the limitation of the electrical bottleneck. Meanwhile, a widely tunable microwave photonic filter (MPF) based on stimulated Brillouin scattering (SBS) is constructed to perform carrier-suppressed single-sideband modulation of LO. Therefore, the proposed photonic frequency downconverter is naturally free from fiber dispersion. Furthermore, thanks to the characteristics of the SBS-based MPF, such as large out-of-band rejection ratio, high resolution and wideband tunability, the proposed system has a high flexibility and downconversion efficiency, which is of great significance for IBFD ROF systems.

4.
Neuroendocrinology ; 112(5): 510-522, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34348341

RESUMEN

INTRODUCTION: Recent studies have suggested that alternative lengthening of telomeres (ALT) is associated with metastasis and poor survival in pancreatic neuroendocrine tumors (PanNETs). This study evaluated whether this association is applicable to Chinese patients as well as the potential somatic mutations associated with ALT. METHODS: We assessed the prevalence of ALT by performing telomere-specific fluorescence in situ hybridization and analyzed DAXX/ATRX expression using immunohistochemistry in 112 Chinese patients with PanNETs to evaluate the association between ALT and clinical outcomes. A subset of the noninsulinoma samples (28/60) was subjected to Sanger sequencing and targeted sequencing. RESULTS: The ALT-positive phenotype was identified in 23.2% (26/112) of the samples. The clinicopathologic factors significantly associated with progression in the noninsulinoma (n = 60) cohort were the female sex (p = 0.006), Ki-67 index (p < 0.001), World Health Organization grade (p = 0.031), and ALT positivity (p = 0.013). Patients with ALT-positive PanNETs had significantly shorter progression-free survival than those with ALT-negative PanNETs in the entire cohort (p < 0.001), noninsulinoma subgroup (p = 0.01), and G2 subgroup (p = 0.001). ALT-positive samples frequently harbored somatic mutations in DAXX, ATRX, MEN1, SETBP1, PRKDC, and GNAS. CONCLUSIONS: We confirmed that ALT positivity is an effective risk predictor, especially in the noninsulinoma and G2 subgroups. ALT is also related to somatic mutations in MEN1, SETBP1, PRKDC, and GNAS, in addition to DAXX and ATRX.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias Pancreáticas , Proteínas Adaptadoras Transductoras de Señales/metabolismo , China , Proteínas Co-Represoras/genética , Proteínas Co-Represoras/metabolismo , Femenino , Humanos , Hibridación Fluorescente in Situ , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Tumores Neuroendocrinos/patología , Neoplasias Pancreáticas/patología , Fenotipo , Telómero/genética , Telómero/metabolismo , Telómero/patología , Homeostasis del Telómero/genética , Proteína Nuclear Ligada al Cromosoma X/genética , Proteína Nuclear Ligada al Cromosoma X/metabolismo
5.
Org Biomol Chem ; 20(18): 3712-3716, 2022 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-35441647

RESUMEN

Cephaloliverols A (1) and B (2), two meroterpenoids based on a sterol and an abietane diterpene possessing a dioxane ring, were isolated from the twigs and leaves of Cephalotaxus oliveri. Their structures were established by spectroscopic analysis and quantum chemical calculation. 1 and 2 represent the first sterol-hybrid meroditerpenoids. The two compounds and their precursors decreased NO production in a dose-dependent manner in LPS-stimulated RAW 264.7 macrophages.


Asunto(s)
Cephalotaxus , Abietanos , Cephalotaxus/química , Estructura Molecular , Hojas de la Planta/química , Esteroles/farmacología
6.
Genet Mol Biol ; 45(2): e20210237, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35275159

RESUMEN

Transfection efficiency was estimated to optimize the conditions for RNA interference (RNAi), including transfection time, validity, and nucleic acid concentration and type, using the EZ Trans Cell Reagent, a cationic polymer. An shRNA against GFP was designed and transfected into cells using the EZ transfection reagent. The shRNA significantly decreased the expression of GFP. In addition, pre-diluted transfection reagent at room temperature and small nucleic acids increased the transfection efficiency, which peaked at 24 h. Compared with circular nucleic acids, linear nucleic acids showed higher transfection efficiency and a higher genome integration rate. We optimized cationic polymer-mediated RNAi conditions, and our data will be useful for future RNAi studies.

7.
Opt Lett ; 46(4): 868-871, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33577534

RESUMEN

A photonic method to generate and transmit quadruple bandwidth dual-band dual-chirp microwave waveforms with immunity to fiber chromatic dispersion induced power fading is proposed and experimentally demonstrated, which is suitable for Doppler blind-speed elimination, small target detection, and multiband detection in multiband radar systems. A dual-polarization dual-parallel Mach-Zehnder modulator is utilized to realize carrier-suppressed harmonic single-sideband modulation of a radio frequency carrier and carrier-suppressed DSB modulation of a baseband single-chirped waveform at two orthogonal polarization states. After photoelectronic conversion, dual-band bandwidth-quadrupling dual-chirp waveforms are generated. Moreover, different from traditional DSB-based dual-chirp signal generation, the generated dual-chirp microwave waveforms can be transmitted over fiber without power fading, which is significant in dual-band radars for one to multiple base station transmissions.

8.
Appl Opt ; 60(16): 4827-4834, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34143036

RESUMEN

Owing to their mighty fitting ability, the supervised learning-based deep-learning (DL) models have been widely used in the area of optical performance monitoring (OPM) to improve the optical monitors' performance. However, the supervised learning-based DL models used in OPM are based on two important premises. The first premise is enough training data with labels; the second premise is the same distribution of the training and test data. Nevertheless, it is hard to meet the two premises in the real-world environment where the optical performance monitors are deployed, since the data are unlabeled and the optical network environment is dynamic (such as component aging caused by slow parameter variation), causing the degradation of the monitoring performance. This is because the supervised learning-based DL models lack the adaptability of the dynamic environment. For the purpose of improving the optical performance monitors' adaptability, we propose a transfer-learning-based convolutional neural network model to maintain the monitoring performance in the dynamic optical network environment. The transfer-learning method can transfer the learned knowledge from the labeled data under an invariant optical network environment to the unlabeled data under a dynamic optical network environment. During the training phase, the maximum mean discrepancy (MMD) is applied to match the features extracted from the source and the target domains. When the trained model is deployed in the OPM monitor, the robustness of the system to the dynamic environment would be enhanced. Four signals (60/100 Gbps 16/64 QAM) under different working environments are used to verify the adaptability of the method. The influence of the MMD's weight rates, batch size, and weight parameters confirmed the effectiveness of our method.

9.
Opt Lett ; 45(5): 1285-1288, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32108827

RESUMEN

We present a photonic approach to generate and transmit a dual-chirp microwave waveform with antidispersion performance. Traditionally, the microwave signal generated based on double-sideband (DSB) modulation suffers from power fading significantly. We propose a DSB-based dual-chirp microwave waveform transmitter that can eliminate the chromatic dispersion-induced power fading (CDIP) over fiber transmission. The CDIP elimination, rather than compensation, ensures that the working bandwidth of the dual-chirp waveform is not limited by the periodical power fading. The proposed signal modulation scheme makes the signal transmitter free from the direct current bias drifting of the modulator. Moreover, thanks to the phase modulation, the generated waveform is background-free. The proposed dual-chirp waveform transmitter features a compact structure, polarization independence, and CDIP elimination, which has great potential in radars for one-to-multibase station fiber transmission.

10.
Opt Lett ; 45(18): 5000-5003, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32932437

RESUMEN

We present a photonic approach to realize radio frequency (RF) down-conversion and intermediate frequency (IF) channel switching for satellite communication. Conventionally, photonic RF mixers always suffer from limitations of one operational state and one IF channel. We proposed a photonic repeater that can realize multiple frequency down-conversion states and different IF channel switching. Two separated RF ports and two independent local oscillator ports ensure the repeater can down-convert RF signals in different bands simultaneously. Based on the characteristic that orthogonally polarized optical signals cannot beat with each other, the crosstalk between different channels is alleviated. Since no optical filters are involved, the repeater can process broadband RF signals down-conversion and broadband IF signals channel switching. The proposed photonic repeater features compact structure, broad and different bands of operation, and no physical optical splitting, which is promising for a satellite payload.

11.
Opt Lett ; 44(14): 3530-3533, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31305565

RESUMEN

We report a photonic scheme to generate a millimeter-wave ultra-wideband (MMW-UWB) pulse based on optoelectronic oscillation (OEO). Normally, a millimeter-wave signal source is essential for the generation of a MMW-UWB pulse. The key novelty of our work is that no millimeter-wave signal source is required. The MMW-UWB pulses are directly generated by truncating an OEO signal into pulses. The principle behind the proposed scheme is analyzed in detail. A proof-of-concept experiment shows that the generated MMW-UWB pulses fit the Federal Communications Commission (FCC) spectral mask very well.

12.
Gynecol Endocrinol ; 33(6): 480-484, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28277121

RESUMEN

OBJECTIVE: The aim of our study is to investigate the expression pattern and prognostic significance of melanoma-associated antigens-A (MAGE-A) family in primary epithelial ovarian cancer (EOC) patients. STUDY DESIGN: The expression of MAGE-A family members, including MAGE-A1, -A2, -A3, -A4, -A6, -A10 and -A12 was immunohistochemically detected in 82 cases of primary EOC and 10 cases of pericarcinoma ovarian tissues. The association between MAGE-A family expression and the clinicopathological parameters as well as the prognosis of primary EOC patients was analyzed. RESULTS: MAGE-A family expressed in 48.8% of primary EOC tissues, but not expressed in pericarcinoma ovarian tissues. MAGE-A expression was associated with the pathological types, FIGO stage, and pre-operative serum CA125 level. Overall survival of EOC patients with positive MAGE-A family expression was significantly shorter than those patients with negative MAGE-A expression. Multivariate analysis showed that although MAGE-A family expression can affect the overall survival, it was not an independent prognostic marker for EOC patients. CONCLUSIONS: Molecular assessment of MAGE-A family members could be helpful to improve the prognostic evaluation and to provide a new potential therapeutic target for primary EOC patients.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias Glandulares y Epiteliales/metabolismo , Neoplasias Ováricas/metabolismo , Carcinoma Epitelial de Ovario , Femenino , Humanos , Masculino , Neoplasias Glandulares y Epiteliales/diagnóstico , Neoplasias Ováricas/diagnóstico , Pronóstico , Estudios Retrospectivos , Testículo/metabolismo
13.
Biomarkers ; 21(1): 80-90, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26631178

RESUMEN

It has been reported that the trimethylation of histone 3 on lysine 27 (H3K27me3) is required for enhancer of zeste homology 2 (EZH2)-mediated repression of various genes essential for tumorigenesis and tumor development. Here, we reported the expression of EZH2 and H3K27me3 in esophageal squamous cell carcinoma (ESCC) specimens was higher than the pericarcinoma esophageal specimens. Their expression was positively associated with the poor prognosis of ESCC patients. EZH2 expression, histological grade and distant lymph node metastasis were all independent factors for poor prognosis of ESCC. In addition, enforced expression of EZH2 in esophageal cancer-derived cells could increase the overall H3K27me3 level. Our results suggested the expression of EZH2 and H3K27me3 could serve as biomarkers in the prediction of ESCC patients' survival and ESCC metastasis.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/genética , Neoplasias Esofágicas/metabolismo , Histonas/metabolismo , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/secundario , Línea Celular Tumoral , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Femenino , Expresión Génica , Humanos , Estimación de Kaplan-Meier , Masculino , Metilación , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Procesamiento Proteico-Postraduccional
14.
Biomarkers ; 19(1): 34-42, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24320162

RESUMEN

Ovarian cancer is a leading cause of death among gynecologic malignancies. In this study, we reported the expression of melanoma-associated antigens A (MAGE-A) genes in peripheral blood from 80 patients with ovarian cancer and 30 healthy donors. MAGE-As expression was associated with the factors indicating poor prognosis. The expressions of MAGE-As and each individual MAGE-A genes were also associated with low overall survival of patients with ovarian cancer. Our results suggested MAGE-A genes may have the potential to be surveillance markers for the detection of circulating tumor cells and represent a poor prognosis for patients with ovarian cancer.


Asunto(s)
Antígeno Ca-125/sangre , Antígenos Específicos del Melanoma/sangre , Neoplasias Quísticas, Mucinosas y Serosas/sangre , Células Neoplásicas Circulantes/metabolismo , Neoplasias Ováricas/sangre , Estudios de Casos y Controles , Femenino , Humanos , Estimación de Kaplan-Meier , Antígenos Específicos del Melanoma/genética , Análisis Multivariante , Neoplasias Quísticas, Mucinosas y Serosas/mortalidad , Neoplasias Quísticas, Mucinosas y Serosas/secundario , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología
15.
Phytochemistry ; 224: 114166, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38810815

RESUMEN

Plants of the Garcinia genus were rich in structurally diverse and naturally bioactive components, while limited studies have been reported for Garcinia pedunculata Roxb. and G. nujiangensis C. Y. Wu & Y. H. Li. Four previously undescribed compounds including three chromones, garpedunchromones A-C (1-3), and one biflavonoid, nujiangbiflavone A (14), along with fifteen known analogs (4-13, 15-19) were isolated from G. pedunculata and G. nujiangensis. The structures of the isolated compounds were determined based on their HRESIMS data, extensive NMR spectroscopic analyses, and ECD calculations. The chromone derivatives were isolated from Garcinia for the first time. Compound 14 was a rare biflavonoid with C-3─C-6″ linkage. The biological evaluation of these isolates against NO production was conducted in the LPS-induced RAW 264.7 cells, resulting in the identification of a series of potent NO inhibitors, of which garpedunchromone B (2) was the most active with an IC50 value of 18.11 ± 0.96 µM. In the network pharmacology studies, the potential targets of compounds and inflammation were obtained from PharmMapper and GeneCards database. GO and KEGG enrichment analysis revealed that the overlapped targets were closely related to the major pathogenic processes linked to inflammation. Garpedunchromone B and proteins binding sites were being predicted.


Asunto(s)
Antiinflamatorios , Biflavonoides , Cromonas , Garcinia , Garcinia/química , Biflavonoides/química , Biflavonoides/farmacología , Biflavonoides/aislamiento & purificación , Cromonas/química , Cromonas/farmacología , Cromonas/aislamiento & purificación , Ratones , Animales , Células RAW 264.7 , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Relación Estructura-Actividad , Estructura Molecular , Lipopolisacáridos/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Relación Dosis-Respuesta a Droga
16.
Diagn Pathol ; 19(1): 113, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39175074

RESUMEN

BACKGROUND: CLDN is a core component of tight junctions (TJs). Abnormal expressions of CLDNs are commonly detected in various types of tumors. CLDNs are of interest as a potential therapeutic target. CLDNs are closely associated with most cancers of epithelial origin, especially when CLDN7 promotes cancer cell metastasis, such as in gastric, cervical, and ovarian cancers.Its expression and prognosis in breast cancer (BC) remain unknown.The purpose of this study was to investigate the expression pattern of CLDN7 and related immune factors in BC and shed light on a better therapeutic avenue for BC patients. METHOD: The cBioPortal, GEPIA, and TCGA databases were used to comprehensively assess the expression of CLDN7 in BC. The Kaplan-Meier Plotter (KMP) database was applied to examine the relationship among the CLDN7 overexpression (OE), prognosis, and overall survival (OS) of BC patients. Immunohistochemical staining was performed on 92 BC tissue samples and 20 benign breast tumors to verify the expression level of CLDN-7 protein and its correlation with clinicopathological features and prognosis. TIMER2.0 was used to analyze the correlation between the CLDN7 OE and immune gene activation using BC-related transcriptomic data. Enrichment analyses of CLDN7-related immune pathways were conducted using online databases. The risk of expression of CLDN7-related immune genes was assessed and differentially expressed (DE) genes were included in the construction of the risk prognosis nomogram. RESULTS: Both database analysis and clinical sample validation results showed that CLDN7 was significantly overexpressed (OE) in BC, and the OE was correlated with poor DFS in BC patients (p < 0.05). TIMER2.0 analysis indicated that CLDN7 OE was negatively associated with the activation of B-cells, CD4+ T-cells, and CD8+ T-cells but positively with the M0 macrophages. Pathway enrichment analysis suggested that CLDN7-related immune factors were mostly involved in the NF-κB and T-cell receptor (TCR) signaling pathways. Univariate Cox regression was used to analyze the correlation between 52 CLDN7 related genes and OS, and 22 genes that are related to prognosis were identified. Prognostic genes were included in the prognostic nomogram of BC with a C-index of 0.76 to predict the 3-year and 5-year OS probabilities of BC individuals. CONCLUSIONS: These findings provide evidence for the role of CLDN7-linked tumor immunity, suggesting that CLDN7 might be a potential immunotherapeutic target for BC, and its association with immune markers could shed light on the better prognosis of BC.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama , Claudinas , Adulto , Femenino , Humanos , Persona de Mediana Edad , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/mortalidad , Claudinas/análisis , Claudinas/genética , Claudinas/metabolismo , Relevancia Clínica , Regulación Neoplásica de la Expresión Génica , Pronóstico , Microambiente Tumoral/inmunología
17.
Plants (Basel) ; 12(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36616321

RESUMEN

Phytochemical investigations of leaves and twigs from Garcinia oligantha Merr. resulted in the isolation of five undescribed triterpene derivatives (1-5) and six known analogs (6-11). Their structures were determined based on extensive spectroscopic data and high-resolution mass spectra analyses. Compounds 1-11 were tested for their in vitro cytotoxicity against three human cancer cell lines (HeLa, HepG-2, and MCF-7). Compounds 1, 2, 8, and 11 exhibited broad and significant cytotoxicity against the tested cell lines with IC50 values ranging from 5.04 to 21.55 µM. Compounds 5 and 9 showed cytotoxicity against HeLa and MCF-7 with IC50 values ranging from 13.22 to 19.62 µM. The preliminary structure-activity relationship for the 11 isolated compounds is also discussed.

18.
Sci Total Environ ; 872: 162298, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-36801328

RESUMEN

After migration in 95 % ethanol (food simulant) at 70 °C for 2 h (accelerated conditions), the cytotoxicity and endocrine-disruption activity of 42 food contact silicone products (FCSPs) obtained from the Chinese market were studied. Of 31 kitchenwares, 96 % showed mild or above cytotoxicity (relative growth rate < 80 %) using the HeLa neutral red uptake test; and 84 % showed estrogenic (64 %), anti-estrogenic (19 %), androgenic (42 %), and anti-androgenic (39 %) activities by the Dual-luciferase reporter gene assay. The mold sample induced late phase HeLa apoptosis as detected by Annexin V-FITC/PI double staining flow cytometry, in addition, the migration of mold sample has a higher risk of endocrine disruption at high temperature usage. Encouragingly, 11 bottle nipples had neither cytotoxic nor hormonal activity. Utilizing multiple mass spectrometry techniques, non-intentionally added substances (NIASs) in 31 kitchenwares were analyzed, and the migration levels of 26 organic compounds and 21 metals were quantified, furthermore, the safe risk of single migrant was evaluated through their special migration limit (SML) or threshold of toxicological concern (TTC). Using "nchoosek" statement and Spearman's correlation analysis in MATLAB, the migration of 38 compounds or combinations including metals, plasticizers, methylsiloxanes, and lubricants, had strong correlation with cytotoxicity or hormonal activity. The coexistence of various chemical substances in migrants leads to complex biological toxicity of FCSPs, so it is very important to detect the toxicity of the final products. The combination of bioassays and chemical analyses are valuable tools to facilitate the identification and analyses of FCSPs and migrants that have potential safety risks.


Asunto(s)
Sistema Endocrino , Elastómeros de Silicona , Cromatografía de Gases y Espectrometría de Masas/métodos , Plastificantes/análisis , Contaminación de Alimentos/análisis
19.
Sci Total Environ ; 829: 154449, 2022 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-35276138

RESUMEN

The analysis, migration, and childhood exposure of methylsiloxanes (MSs) in 32 silicone infant bottle nipples marketed in China were studied. Thirty types of MSs in two families, which included 11 linear MSs (LMSs, L4-L14) and 19 cyclic MSs (CMSs, D4-D22), were identified using gas chromatography-mass spectrometry (GC-MS) associated with standards, retention index, and carbon number rule. In 32 nipples, MSs with molecular weight < 1000 Da and CMSs were predominant. Considering the actual daily use of bottle nipples, the migration tests of MSs from nipples to artificial saliva and reconstituted powdered formula were performed. In particular, the orthogonal test design-QuEChERS-GC/MS was employed to detect MSs in formula. The median migration level of ΣMSs (MW < 1000 Da) in formula was 950.9 ng/mL, which was much higher than that in artificial saliva (98.1 ng/mL). If formula is fed to children aged 3-36 months using bottle nipples according to product instructions, the daily oral exposure to ΣMSs (MW < 1000) for children ranged from 52 to 146 µg/kg bw-day, which were two to five orders of magnitude higher than those of other exposure pathways. In sum, oral intake (especially through formula) may be the predominant pathway of exposure of MSs in children. This research enhances our understanding of the oral exposure risks of MSs and provides useful information that could aid the development of risk management strategies.


Asunto(s)
Pezones , Siliconas , Alimentación con Biberón , Niño , Cromatografía de Gases y Espectrometría de Masas , Humanos , Lactante , Saliva Artificial
20.
Contrast Media Mol Imaging ; 2021: 5294379, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34354553

RESUMEN

This paper aimed to explore the adoption of deep learning algorithms in lung cancer spinal bone metastasis diagnosis. Comprehensive analysis was carried out with the aid of AdaBoost algorithm and Chan-Vese (CV) algorithm. 87 patients with lung cancer spinal bone metastasis were taken as research subjects, and comprehensive evaluation was made in terms of preliminary classification of images, segmentation results, Dice index, and Jaccard coefficient. After the case of misjudgment on whether there was hot spot was excluded, the initial classification accuracy of the AdaBoost algorithm can reach 96.55%. True positive rate (TPR) was 2.3%, and false negative rate (FNR) was 1.15%. 45 MRI images with hot spots were utilized as test set to detect the segmentation accuracy of CV, maximum between-cluster variance method (OTSU), and region growing algorithm. The results showed that the Dice index and Jaccard coefficient of the CV algorithm were 0.8591 and 0.8002, respectively, which were considerably superior to OTSU (0.6125 and 0.5541) and region growing algorithm (0.7293 and 0.6598). In summary, the AdaBoost algorithm was adopted for image preliminary classification, and CV algorithm for image segmentation was ideal for the diagnosis of lung cancer spinal bone metastasis and it was worthy of clinical promotion.


Asunto(s)
Algoritmos , Neoplasias Óseas/secundario , Aprendizaje Profundo , Procesamiento de Imagen Asistido por Computador/métodos , Neoplasias Pulmonares/patología , Imagen por Resonancia Magnética/métodos , Neoplasias de la Columna Vertebral/secundario , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
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