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Data rate and security are essential performance metrics for passive optical networks (PON). However, existing optical access networks lack standardized metrics to evaluate rate and security performance uniformly. This paper introduces a high-speed and security joint optimization scheme for optical access networks using convex optimization. Evaluation metrics for data rate and security performance in PON are established. According to the evaluation metrics, the security optimization objective function Us, high-speed optimization objective function GMI, and high-speed security joint-optimization objective function Hs are established. An optimization problem is formulated to maximize weighted rate and security indicators, factoring in constraints such as maximum power, probability, amplifier capacity, normalized mutual information, and key and frame lengths. An alternating optimization method is applied to iteratively address sub-problems by exploiting successive convex approximations and differences of convex functions. This transforms non-convex sub-problems into convex optimizations. Experimental results highlight notable improvements in objective function values, confirming the effectiveness of the proposed high-speed security optimization algorithm for optical access networks.
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The AlGaN-based deep ultraviolet light-emitting diode (DUV LED) has advantages of environmentally friendly materials, tunable emission wavelength, and easy miniaturization. However, an increase in Al composition leads to a decline in the lattice quality, thereby reducing the internal quantum efficiency (IQE). In addition, the light extraction efficiency (LEE) is limited due to the strong transverse magnetization polarization emission from the multiple quantum wells. Here, we designed the topological corner structure in AlGaN-MQWs, and the high electric field intensity in a tiny space at the corner results in an extremely high local density of optical states (LDOS), which could shorten the luminescence decay time of the emitter and increase the radiative rate by 26 times. Meanwhile, because the excited topological corner state resonance mode is a transverse-electric mode, enhancing only the transverse-electric luminescence without any gain for transverse-magnetic luminescence, thereby significantly improving the light extraction efficiency. Finally, according to theoretical calculations, the IQE could reach 68.75% at room temperature.
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Nitrite ion is one of the materials widely used in human life, and the accurate, sensitive and stable detection of nitrite ions is of great significance to people's healthy life. In this study, nitrogen-doped fluorescent carbon dots (N-CDs) for detecting nitrite salt solutions were prepared using citric acid monohydrate and Chrysoidin as precursors through a one-pot hydrothermal method. Under the condition of pH = 3, a noticeable quenching phenomenon occurred in the carbon dot solution with the increase in nitrite ion concentration. This quenching effect might be attributed to the diazonium effect. N-CDs have been successfully used as fluorescence probes for NO2- detection. NO2- can effectively quench the fluorescence intensity of N-CDs, providing a linear response to fluorescence quenching efficiency with respect to NO2- concentration within the range of 0-10µM and 10-30µM, and a detection limit of 52nM, showing high sensitivity. In addition, the probe was applied to the determination of NO2- in ham sausage samples with a detection limit of 0.67µM and recoveries in the range of 99.5-102.3%, the fluorescent probe showed satisfactory reliability.
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With the expansion of human activities, the consequent influx of mercury (Hg) into the food chain and the environment is seriously threatening human life. Herein, nitrogen and sulfur co-doped fluorescent carbon quantum dots (yCQDs) were prepared via a hydrothermal method using o-phenylenediamine (OPD) and taurine as precursors. The morphological characteristics as well as spectral features of yCQDs indicated that the photoluminescence mechanism should be the molecular state fluorophores of 2, 3-diaminophenothiazine (oxOPD), which is the oxide of OPD. The as-synthesized yCQDs exhibited sensitive recognition of Hg2+. According to the investigation in combination of UV-Vis absorption spectra, time-resolved fluorescence spectra and quantum chemical calculations, the abundant functional groups on the surface of yCQDs allowed Hg2+ to bind with yCQDs through various interactions, and the formed complexes significantly inhibited the absorption of excitation light, resulting in the static fluorescence quenching of yCQDs. The proposed yCQDs was utilized for Hg2+ sensing with the limit of detection calculated to be 4.50 × 10- 8 M. Furthermore, the recognition ability of yCQDs for Hg2+ was estimated in tap water, lake water and bottled water, and the results indicated that yCQDs have potential applications in monitoring Hg2+.
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Herein, a fluorescent "on-off-on" nanosensor based on N,S-CDs was developed for highly precise and sensitive recognition of Hg2+ and ampicillin (AMP). Nitrogen and sulfur co-doped carbon dots with blue fluorescence were synthesized by one-pot hydrothermal method using ammonium citrate and DL-methionine as precursors. N,S-CDs exhibited a surface abundant in -OH, -COOH, and -NH2 groups, aiding in creating non-fluorescent ground state complexes when combined with Hg2+, leading to the suppression of N,S-CDs' fluorescence. Subsequent to additional AMP application, the mixed system's fluorescence was restored. Based on this N,S-CDs sensing system, the thresholds for detection for AMP and Hg2+ were discovered to be 0.121 µM and 0.493 µM, respectively. Furthermore, this methodology proved effective in identifying AMP in real samples of tap and lake water, yielding satisfactory results. Consequently, in the area of bioanalysis in intricate environmental sample work, the sensing system showed tremendous promise.
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In this paper, we obtained nitrogen and phosphorus co-doped carbon dots through a hydrothermal method using o-phenylenediamine and citric acid in a 40% phosphoric acid environment. The carbon dots emitted fluorescence at 476 nm under excitation at 408 nm and exhibited good selectivity and high sensitivity towards mercury ions. These carbon dots showed excellent dispersibility in water and maintained stable fluorescence even in high concentration salt environments. The interaction between mercury ions and functional groups on the carbon dots surface through electrostatic interaction resulted in static quenching. Simultaneously, by detecting the lifetime and transient absorption spectra of the carbon dots, we observed that the coordination of mercury ions with the carbon dots broadened the band structure of the carbon dots, and the existing photoinduced electron transfer process increased the non-radiative transition channel. The combined effect of dynamic quenching and static quenching significantly reduced the fluorescence intensity of the carbon dots at 476 nm. The carbon dots exhibited linear detection of mercury ions in the range of 0.01-1 µM, with a detection limit as low as 0.0245 µM. In terms of practical water environmental detection applications, these carbon dots were able to effectively detect mercury ions in tap water and lake water, demonstrating their broad application prospects in the field of environmental metal analysis.
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Herein, we developed a sophisticated dual-mode sensor that utilized 3-aminophenylboric acid functionalized carbon dots (APBA-CDs) to accurately detect uric acid (UA). Our innovative process involved synthesizing APBA-CDs that emitted at 369 nm using a one-step hydrothermal method with 3-aminophenylboric acid and L-glutamine as precursors, ethanol and deionized water as solvents. Once UA was introduced to the APBA-CDs, the fluorescence of the system became visibly quenched. The results of Zeta potential, Fourier transformed infrared (FTIR) spectra, fluorescence lifetime, and other characteristics were analyzed to determine that the reaction mechanism was static quenching. This meant that after UA was mixed with APBA-CDs, it combined with the boric acid function on the surface to form complexes, resulting in a decrease in fluorescence intensity and a blue shift in the absorption peak at about 295 nm in the Ultraviolet-visible (UV-vis) absorption spectra. We were pleased to report that we have successfully used the dual-reading platform to accurately detect UA in serum and human urine. It provided a superior quantitative and visual analysis of UA without the involvement of enzymes. We firmly believe that our innovative dual-mode sensor has immense potential in the fields of biosensing and health monitoring.
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Nitrogen, boron co-doped carbon quantum dots (gCQDs), and a coloration probe (PPD-NPs) with response to cobalt ions (Co2+) were prepared by using 4-hydroxyphenylboric acid as the common precursor, with ethylenediamine and p-phenylenediamine (PPD) adopted as nitrogen-doped reagents, respectively. A noticeable brown-to-purple color change can be observed with the addition of Co2+, and a broad absorption band emerges at 535 nm. At the same time, gCQDs, which is introduced as the fluorescence signal source, will be significantly quenched due to the enhanced inner filtration effect, induced by the overlap between the emission spectrum of gCQDs and the emerging absorption band. Therefore, a colorimetric/fluorescent dual-mode sensing probe for Co2+ is constructed by combining the recognition unit PPD-NPs and the fluorescent gCQDs into PPD-NP/gCQD. Under the optimized experimental conditions, the calculated limits of detection are 1.51 × 10-7 M and 3.75 × 10-7 M for the colorimetric mode and the fluorescence mode, respectively, well qualified for the determination of Co2+ maximum permitted level in drinking water. The feasibility of the proposed method has been verified in tap water, lake water, and black tea samples.
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A ratiometric fluorescence probe based on carbon quantum dots with 420 nm emission (bCQDs) and a p-phenylenediamine-derived fluorescence probe with 550 nm emission (yprobe) is constructed for the detection of Mn2+. The presence of Mn2+ results in the enhanced absorption band at 400 nm of yprobe, and the fluorescence of yprobe is significantly enhanced based on the chelation-enhanced fluorescence mechanism. The fluorescence of bCQDs is then quenched based on the inner filtration effect. The ratio (I550/I420) linearly increases with the increase of Mn2+ concentration within 2.00 × 10-7-1.50 × 10-6 M, and the limit of detection is 1.76 × 10-9 M. Given the fluorescence color changing from blue to yellow, the visual sensing of Mn2+ is feasible based on bCQDs/yprobe coupled with RGB value analysis. The practicability of the proposed method has been verified in tap water, lake water, and sparkling water beverage, indicating that bCQDs/yprobe has promising application in Mn2+ monitoring.
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The wide dynamic range of serum proteome restrained discovery of clinically interested proteins in large cohort studies. Herein, we presented a high-sensitivity, high-throughput, and precise pan-targeted serum proteomic strategy for highly efficient cancer serum proteomic research and biomarker discovery. We constructed a resource of over 2000 cancer-secreted proteins, and the standard MS assays and spectra of at least one synthetic unique peptide per protein were acquired and documented (Cancer Serum Atlas, www.cancerserumatlas.com). Then, the standard peptide-anchored parallel reaction monitoring (SPA-PRM) method was developed with support of the Cancer Serum Atlas, achieving precise quantification of cancer-secreted proteins with high throughput and sensitivity. We directly quantified 325 cancer-related serum proteins in 288 serums of four cancer types (liver, stomach, lung, breast) and controls with the pan-targeted strategy and discovered considerable potential biomarker benefits for early detection of cancer. Finally, a proteomic-based multicancer detection model was built, demonstrating high sensitivity (87.2%) and specificity (100%), with 73.8% localization accuracy for an independent test set. In conclusion, the Cancer Serum Atlas provides a wide range of potential biomarkers that serve as targets and standard assays for systematic and highly efficient serological studies of cancer. The Cancer Serum Atlas-supported pan-targeted proteomic strategy enables highly efficient biomarker discovery and multicancer detection and thus can be a powerful tool for liquid biopsy.
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Neoplasias , Proteômica , Humanos , Proteômica/métodos , Biomarcadores/metabolismo , Neoplasias/diagnóstico , Proteínas Sanguíneas , Peptídeos , ProteomaRESUMO
BACKGROUND: Genitourinary small cell carcinoma is rare, and has a poor prognosis. However, effective treatment options for this disease are limited. We present a study to assess the efficacy of chemotherapy alone or combined with immunotherapy for locally advanced or metastatic genitourinary small cell carcinoma (GSCC). METHODS: We performed a retrospective analysis of patients with locally advanced or metastatic GSCC from Jan 2013 to September 2022 at Sun Yat-sen University Cancer Center. The survival and safety profiles were analyzed. RESULTS: Forty-two GSCC patients were enrolled, which included 20 with chemotherapy plus immunotherapy and 22 with chemotherapy alone. The median follow-up time was 15.13 months (95% CI, 8.84-21.42). The addition of immunotherapy to chemotherapy demonstrated no significant difference in median progression-free survival (p = 0.37). However, the median overall survival (OS) was 22.97 and 14.03 months with immunotherapy plus chemotherapy and chemotherapy alone, respectively (HR = 0.69, 95%CI 0.08-0.55, p = 0.017). Two patients with immunotherapy plus chemotherapy achieved clinical complete remission. The overall response rate for patients receiving chemotherapy combined with immunotherapy was 65%, which was higher in comparison to those treated with chemotherapy alone (50%). Univariate and multivariate analyses demonstrated that chemotherapy combined with immunotherapy independently achieved favorable OS. Four patients experienced immunotherapy-related adverse events, with one developing grade 3 hypothyroidism. CONCLUSIONS: Among patients with locally advanced or metastatic GSCC, immunotherapy combined with chemotherapy might be thought of as a potentially effective treatment option for patients with GSCC.
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Carcinoma de Células Pequenas , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Imunoterapia/efeitos adversosRESUMO
Studies of non-linguistic statistical learning (SL) have often linked performance in SL tasks with differences in language outcomes. Most of these studies have focused on Western and high-income educational contexts, but children worldwide learn in radically different educational systems and communities, and often in a second language. In the west African nation of Côte d'Ivoire, children enter fifth grade (CM-1) with widely varying ages and literacy skills. Across three iteratively-developed experiments, 157 children, age 8-15 years, in rural communities in the greater-Adzópe region of Côte d'Ivoire watched sequences of cartoon images with embedded triplet patterns on touchscreen tablets, while performing a target-detection task. We assessed these tablet-based adaptations of non-linguistic visual SL and asked whether the children's individual differences in performance on the SL tasks were related to their first and second language and literacy skills. We found group-level evidence that children used the statistical regularities in the image sequence to gradually decrease their response times, but their responses on post-test discrimination did not reflect this learning. When evaluating the correlation between SL and language skills, individual differences related to other task demands predicted oral language skills shared by first and second languages, while SL better predicted second language print skills. These findings suggest that non-linguistic SL paradigms can measure similar skills in Ivorian children as previous samples, but they also echo recent calls for further cross-cultural validation, greater internal reliability, and tests for confounding variables (such as processing speed) in studies of individual differences in statistical learning. RESEARCH HIGHLIGHTS: We iteratively adapted three visual statistical learning studies for children in rural Côte d'Ivoire. Group-level analyses indicates that the children learn the underlying statistical regularities. Individual-differences analyses reveal some evidence that the statistical learning measure is also correlated with task demands that may be driven by cross-cultural differences. Like previous research, statistical learning is correlated with second language literacy, but we did not find a relationship between SL and oral language skills in first and second languages.
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The present study proposes a new approach for detecting trace amounts of creatinine (Cre) through the utilization of a fluorescence sensor system consisting of nitrogen doped carbon dots (NCDs) and gold ions (Au3+). Yellow fluorescent carbon dots were prepared using a one-step hydrothermal method with o-phenylenediamine and isopropanol as raw materials. First, gold ions are reduced to gold nanoparticles (Au NPs), which bind to NCDs, resulting in electron transfer and fluorescence quenching of NCDs. After adding creatinine, Cre and Au NPs were preferentially combined to form non-fluorescent complexes, and the NCDs fluorescence was restored. The study achieved a detection limit of 1.06 × 10-7 M for Au3+ and 9.29 × 10-9 M for creatinine, indicating a high level of sensitivity. The sensing system has also been successfully utilized for detecting Au3+ in lake water and Cre in human urine, indicating its promising potential and practical applications in the areas of environmental monitoring and biosensing.
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In this paper, we proposed an efficient method for mercury(II) and glutathione detection using a fluorescent nanoprobe as a sensor. Carbon dots were synthesized from polyethyleneimine and ammonium citrate via a one-step hydrothermal method. The fluorescence of carbon dots was quenched since electron transfer occurred due to the interaction between mercury(II) and functional groups on the surface of carbon dots. Adding glutathione to the carbon dots-mercury(II) system, the fluorescence was recovered due to the stronger binding ability of glutathione to mercury(II). Based on the above-mentioned principle, this "off-on" fluorescent sensor can easily achieve the detection of mercury(II) and glutathione, which provided limits of detection of 22.45 nM and 61.89 nM, respectively. In this paper, the proposed method has been applied to detect mercury(II) and glutathione in real lake water and serum, respectively, and a logic gate for sensing glutathione was presented. The developed "off-on" fluorescent sensor with high sensitivity and selectivity has shown great potential for mercury(II) and glutathione detection in environmental and biosensing fields.
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Following an in-depth analysis of one-dimensional chaos, a randomized selective autoencoder neural network (AENN), and coupled chaotic mapping are proposed to address the short period and low complexity of one-dimensional chaos. An improved method is proposed for synchronizing keys during the transmission of one-time pad encryption, which can greatly reduce the usage of channel resources. Then, a joint encryption model based on randomized AENN and a new chaotic coupling mapping is proposed. The performance analysis concludes that the encryption model possesses a huge key space and high sensitivity, and achieves the effect of one-time pad encryption. Experimental results show that this model is a high-security joint encryption model that saves secure channel resources and has the ability to resist common attacks, such as exhaustive attacks, selective plaintext attacks, and statistical attacks.
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A neuropathologic hallmark of Alzheimer's disease (AD) is the presence of senile plaques that contain neurotoxic amyloid-ß protein (Aß) species, which are generated by the cleavage of amyloid ß-protein precursor by secretases such as the γ-secretase complex, preferentially located in detergent-resistant membrane (DRM) regions and comprising endoproteolysed amino- and carboxy-terminal fragments of presenilin, nicastrin, anterior pharynx defective 1 and presenilin enhancer 2. Whereas some of familial AD patients harbor causative PSEN mutations that lead to more generation of neurotoxic Aß42, the contribution of Aß generation to sporadic/late-onset AD remains unclear. We found that the carboxy-terminal fragment of presenilin 1 was redistributed from DRM regions to detergent-soluble membrane (non-DRM) regions in brain tissue samples from individuals with sporadic AD. DRM fractions from AD brain sample had the ability to generate significantly more Aß and had a lower cholesterol content than DRM fractions from non-demented control subjects. We further demonstrated that lowering the cholesterol content of DRM regions from cultured cells contributed to the redistribution of γ-secretase components and Aß production. Taken together, the present analyses suggest that the lowered cholesterol content in DRM regions may be a cause of sporadic/late-onset AD by enhancing overall Aß generation.
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Doença de Alzheimer/patologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Colesterol/metabolismo , Microdomínios da Membrana/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Microdomínios da Membrana/metabolismo , Mutação , Presenilina-1/genética , Presenilina-2/genéticaRESUMO
BACKGROUND: The role of first-line of immunotherapy in metastatic urothelial carcinoma (mUC) remains unclear. This meta-analysis aimed to explore an optimal first-line treatment strategy for mUC patients. METHODS: We carried out a meta-analysis between chemo-immunotherapy, immunotherapy, and chemotherapy in mUC based on randomized trials. The outcomes included overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events (AEs). A fixed-effect or random-effects model was adopted depending on between-study heterogeneity. RESULTS: Three trials involving 3238 patients were included. PD-1/PD-L1 inhibitor plus platinum-based chemotherapy was associated with the improvements of OS (HR, 0.85; 95% CI 0.75-0.99), PFS (HR, 0.80; 95% CI 0.71-0.90) and ORR (OR, 1.32; 95% CI 1.07-1.63) when compared with platinum-based chemotherapy, but not with better DCR (OR, 1.07; 95% CI 0.78-1.46). PD-1/PD-L1 inhibitor alone was associated with worse ORR (OR, 0.38; 95% CI 0.17-0.87) and DCR (OR, 0.20; 95% CI 0.16-0.25) when compared with platinum-based chemotherapy while it did not statistically reduce the risk of mortality (HR 0.97 for entire cohort; 0.90 for PD-L1 high cohort). In safety analyses, the incidence of adverse events (AEs) between regimens showed no difference, but the frequency of AEs of grade 3 or severity was higher in chemo-immunotherapy compared to chemotherapy. CONCLUSIONS: Compared with platinum-based chemotherapy, chemo-immunotherapy is associated with significantly improved PFS, OS, and ORR in the first-line therapy for mUC at the expanse of increased toxicity.
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Carcinoma de Células de Transição , Neoplasias Pulmonares , Neoplasias da Bexiga Urinária , Carcinoma de Células de Transição/tratamento farmacológico , Feminino , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia , Neoplasias Pulmonares/patologia , Masculino , Platina/uso terapêutico , Receptor de Morte Celular Programada 1 , Neoplasias da Bexiga Urinária/tratamento farmacológicoRESUMO
Highly sensitive ultraviolet (UV) photodetectors are highly desired for industrial and scientific applications. However, the responsivity of silicon photodiodes in the UV wavelength band is relatively low due to high-density Si/SiO2 interface states. In this paper, a coplanar avalanche photodiode (APD) was developed with a virtual guard ring design. When working in Geiger mode, it exhibited a strong UV response. The responsivity of 4 × 103 A/W (corresponding to a gain of 8 × 106) at 261 nm is measured under the incident power of 0.6 µW with an excess bias of 1.5 V. To the best of our knowledge, the maximum 3-dB bandwidth of 1.4 GHz is the first report ever for a Si APD when working in the Geiger mode in spite of the absence of an integrated CMOS read-out circuit.
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BACKGROUNDS: Triple negative breast cancer (TNBC) is a heterogeneous disease with more aggressive clinical courses than other subtypes of breast cancer. In this study, we performed high-resolution mass spectrometry-based quantitative proteomics with TNBC clinical tissue specimens to explore the early and sensitive diagnostic signatures and potential therapeutic targets for TNBC patients. METHODS: We performed an iTRAQ labeling coupled LC-MS/MS approach to explore the global proteome in tumor tissues and corresponding para-tumor tissues from 24 patients with grade I-II and grade III primary TNBC. Relative peptide quantification and protein identification were performed by Proteome Discoverer™ software with Mascot search engine. Differentially expressed proteins were analyzed by bioinformatic analyses, including GO function classification annotation and KEGG enrichment analysis. Pathway analyses for protein-protein interactions and upstream regulations of differentially expressed candidates were performed by Ingenuity Pathway Analysis (IPA) software. RESULTS: Totally, 5401 unique proteins were identified and quantified in different stage of TNBCs. 845 proteins were changed in patients with grade I or II TNBC, among which 304 were up-regulated and 541 were down-regulated. Meanwhile, for patients with grade III TNBC, 358 proteins were increased and 651 proteins were decreased. Comparing to para-cancerous tissues, various signaling pathways and metabolic processes, including PPAR pathways, PI3K-Akt pathway, one-carbon metabolism, amino acid synthesis, and lipid metabolism were activated in TNBC cancer tissues. Death receptor signaling was significantly activated in grade I-II TNBCs, however, remarkably inhibited in grade III TNBCs. Western blot experiments were conducted to validate expression levels of CYCS, HMGA1 and XIAP with samples from individual patients. CONCLUSIONS: Overall, our proteomic data presented precise quantification of potential signatures, signaling pathways, regulatory networks, and characteristic differences in each clinicopathological subgroup. The proteome provides complementary information for TNBC accurate subtype classification and therapeutic targets research.
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Neoplasias de Mama Triplo Negativas , Cromatografia Líquida , Humanos , Fosfatidilinositol 3-Quinases , Proteômica , Espectrometria de Massas em Tandem , Neoplasias de Mama Triplo Negativas/genéticaRESUMO
Serum/plasma holds promise as an important source of disease-related proteins and even biomarkers in clinical practice. However, the discovery of biomarker candidates in serum/plasma remains challenging. In this study, we constructed an MS strategy that enables the fast and precise quantification of serum biomarkers through coupling a high-throughput scheduled MRM strategy with a stable isotope-labelled (SIL) peptide panel from more than 500 plasma proteins as internal standards. With this strategy, we discovered relevant serum proteins of atherosclerosis (AS), lung cancer (LC) and breast cancer (BC), which can simultaneously recognize these diseases. The results indicate that the powerful strategy we constructed has the potential for serum biomarker screening and disease detection.