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1.
Langmuir ; 40(24): 12689-12696, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38842226

RESUMO

Maleic anhydride (MAH)-modified polymers are used as tie layers for binding dissimilar polymers in multilayer polymer films. The MAH chemistry which promotes adhesion is well characterized in the bulk; however, only recently has the interfacial chemistry been studied. Sum frequency generation vibrational spectroscopy (SFG) is an interfacial spectroscopy technique which provides detailed information on interfacial chemical reactions, species, and molecular orientations and has been essential for characterizing the MAH chemistry in both nylon and ethyl vinyl alcohol copolymer (EVOH) model systems and coextruded multilayer films. Here, we further characterize the interfacial chemistry between MAH-modified polyethylene tie layers and both EVOH and nylon by investigating the model systems over a range of MAH concentrations. We can detect the interfacial chemical reaction products between MAH and the barrier layer at MAH concentrations of ≥0.022 wt % for nylon and ≥0.077 wt % for EVOH. Additionally, from the concentration-dependent reaction reactant/product SFG peak positions and the product imide or ester/acid C═O group tilt angles extracted from the polarization-dependent SFG spectra, we quantitatively observe concentration-dependent changes to both the interfacial chemistry and interfacial structure. The interfacial chemistry and molecular orientation as a function of MAH concentration are well correlated with the adhesion strength, providing important quantitative information for the future design of MAH-modified tie layers for a variety of important applications.

2.
Bioresour Technol ; 406: 130937, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38852892

RESUMO

Thermal hydrolyzed sludge (THS) exhibits considerable promise in generating medium-chain fatty acids (MCFAs) through chain elongation (CE) technology. This study developed a novel continuous CE process using THS as the substrate, achieving an optimal ethanol loading rate (5.8 g COD/L/d) and stable MCFA production at 10.9 g COD/L, with a rate of 3.6 g COD/L/d. The MCFAs primarily comprised n-caproate and n-caprylate, representing 41.5 % and 54.3 % of the total MCFAs, respectively. Utilization efficiencies for ethanol and acetate were nearly complete at 100 % and 92.8 %, respectively. Key microbial taxa identified under these optimal conditions included Alcaligenes, SRB2, Sporanaerobacter, and Kurthia, which were instrumental in critical pathways such as the generation of acetyl-CoA, the initial carboxylation of acetyl-CoA, the fatty acid biosynthesis cycle, and energy metabolism. This research provides a theoretical and technical blueprint for converting waste sludge into valuable MCFAs, promoting sustainable waste-to-resource strategies.

3.
Proc Natl Acad Sci U S A ; 121(25): e2406788121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38865267

RESUMO

Heritable symbionts are common among animals in nature, but the molecular mechanisms underpinning symbiont invasions of host populations have been elusive. In this study, we demonstrate the spread of Rickettsia in an invasive agricultural pest, the whitefly Bemisia tabaci Mediterranean (MED), across northeastern China from 2018 to 2023. Here, we show that the beneficial symbiont Rickettsia spreads by manipulating host hormone signals. Our analyses suggest that Rickettsia have been horizontally acquired by B. tabaci MED from another invasive whitefly B. tabaci Middle East-Asia Minor 1 during periods of coexistence. Rickettsia is transmitted maternally and horizontally from female B. tabaci MED individuals. Rickettsia infection enhances fecundity and results in female bias among whiteflies. Our findings reveal that Rickettsia infection stimulates juvenile hormone (JH) synthesis, in turn enhancing fecundity, copulation events, and the female ratio of the offspring. Consequently, Rickettsia infection results in increased whitefly fecundity and female bias by modulating the JH pathway. More female progeny facilitates the transmission of Rickettsia. This study illustrates that the spread of Rickettsia among invasive whiteflies in northeastern China is propelled by host hormone regulation. Such symbiont invasions lead to rapid physiological and molecular evolution in the host, influencing the biology and ecology of an invasive species.


Assuntos
Fertilidade , Hemípteros , Rickettsia , Razão de Masculinidade , Simbiose , Animais , Rickettsia/fisiologia , Hemípteros/microbiologia , Hemípteros/fisiologia , Feminino , Masculino , Hormônios Juvenis/metabolismo , China
4.
Soft Matter ; 20(24): 4765-4775, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38841820

RESUMO

Silicones have excellent material properties and are used extensively in many applications, ranging from adhesives and lubricants to electrical insulation. To ensure strong adhesion of silicone adhesives to a wide variety of substrates, silane-based adhesion promotors are typically blended into the silicone adhesive formulation. However, little is known at the molecular level about the true silane adhesion promotion mechanism, which limits the ability to develop even more effective adhesion promoters. To understand the adhesion promotion mechanism of silane molecules at the molecular level, this study has used sum frequency generation vibrational spectroscopy (SFG) to determine the behavior of (3-glycidoxypropyl)trimethoxy silane (γ-GPS) at the buried interface between poly(ethylene terephthalate) (PET) and a bulk silicone adhesive. To complement and extend the SFG results, atomistic molecular dynamics (MD) simulations were applied to investigate molecular behavior and interfacial interaction of γ-GPS at the silicone/PET interface. Free energy computations were used to study the γ-GPS interaction in the sample system and determine the γ-GPS interfacial segregation mechanism. Both experiments and simulations consistently show that γ-GPS molecules prefer to segregate at the interface between PET and PDMS. The methoxy groups on γ-GPS molecules orient toward the PDMS polymer phase. The consistent picture of interfacial structure emerging from both simulation and experiment provides enhanced insight on how γ-GPS behaves in the silicone - PET system and illustrates why γ-GPS could improve the adhesion of silicone adhesive, leading to further understanding of silicone adhesion mechanisms useful in the design of silicone adhesives with improved performance.

5.
Huan Jing Ke Xue ; 45(6): 3205-3213, 2024 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-38897744

RESUMO

To improve the accuracy and stability of water quality prediction in the Pearl River Estuary, a water quality prediction model was proposed based on BiLSTM improved with an attention mechanism. The feature attention mechanism was introduced to enhance the ability of the model to capture important features, and the temporal attention mechanism was added to improve the mining ability of time series correlation information and water quality fluctuation details. The new model was applied to the water quality prediction of eight estuaries of the Pearl River, and the prediction performance test, generalization ability test, and characteristic parameter expansion test were carried out. The results showed that:① The new model achieved high prediction accuracy in the water quality prediction of the Zhuhaidaqiao section. The root-mean-square error (RMSE) between the predicted value and the measured value was 0.004 1 mg·L-1, and the coefficient of determination (R2) was 98.3 %. Compared with that of Multi-BiLSTM, Multi-LSTM, BiLSTM, and LSTM, the results showed that the new model had the highest prediction accuracy, which verified the accuracy of the model. ② Both the number of training samples and the number of forecasting steps affected the prediction accuracy of the model, and the prediction accuracy of the model increased with the increase of the training samples. When predicting the total phosphorus of the Zhuhaidaqiao section, more than 240 training samples could obtain higher prediction accuracy. Increasing the number of prediction steps caused the prediction accuracy of the model to decline rapidly, and the reliability of the model prediction could not be guaranteed when the number of prediction steps was greater than 5. ③ When the new model was applied to the prediction of different water quality indexes in eight estuaries of the Pearl River, the prediction results had high precision and the model had strong generalization ability. The input data of upstream water quality, rainfall, and other characteristic parameters associated with the section prediction index of the object could improve the prediction accuracy of the model. Through many tests, the results showed that the new model could meet the requirements of precision, applicability, and expansibility of water quality prediction in the Pearl River Estuary and thus is a new exploration method for high-precision prediction of water quality in complex hydrodynamic environments.

7.
World J Gastrointest Surg ; 16(4): 1078-1086, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38690039

RESUMO

BACKGROUND: Benign gallbladder diseases have become a high-prevalence condition not only in China but also worldwide. The main types of benign gallbladder diseases include gallbladder polyps, acute and chronic cholecystitis, and gallstones, with gallstones being the most common, accounting for over 70% of cases. Although the mortality rate of benign gallbladder diseases is low, they carry obvious potential risks. Studies have shown that an increased incidence of benign gallbladder diseases can increase the risk of cardiovascular diseases and gallbladder cancer, resulting in a substantial disease burden on patients and their families. AIM: To assess the medical utility of the Configuration-Procedure-Consequence (CPC) three-dimensional quality evaluation model in modulating the prognosis of laparoscopic cholecystectomy patients. METHODS: A total of 98 patients who underwent laparoscopic cholecystectomy in our hospital from February 2020 to January 2022 were selected as the subjects. According to the random number table method, they were divided into a study group and a control group, with 49 patients in each group. The control group received routine perioperative care, while the study group had the addition of the CPC three-dimensional quality evaluation. The postoperative recovery-related indicators (time to first flatus, time to oral intake, time to ambulation, hospital stay), stress indicators (cortisol and adrenaline levels), distinctions in anxiety and depression status, and the incidence of perioperative complications were compared. RESULTS: The time to first flatus, time to oral intake, time to ambulation, and hospital stay of the study group patients were obviously lower than those of the control group patients, with statistical significance (P < 0.05). On the 1st day after admission, there were no obvious distinctions in cortisol and adrenaline levels in blood samples, as well as in the Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS) scores between the study group and the control group (P > 0.05). However, on the 3rd day after surgery, the cortisol and adrenaline levels, as well as SAS and SDS scores of the study group patients, were obviously lower than those of the control group patients (P < 0.05). The study group had 2 cases of incisional infection and 1 case of pulmonary infection, with a total incidence of complications of 6.12% (3/49), which was obviously lower than the 20.41% (10/49) in the control group (P < 0.05). CONCLUSION: Implementing the CPC three-dimensional quality evaluation model for patients undergoing laparoscopic cholecystectomy can help accelerate their perioperative recovery process, alleviate perioperative stress symptoms, mitigate anxiety, depression, and other adverse emotions, and to some extent, reduce the incidence of perioperative complications.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38702168

RESUMO

Objective: Type 2 diabetes mellitus (T2DM) is strongly associated with obesity, a significant risk factor for the occurrence and progression of chronic kidney disease. In recent years, weight loss surgery has become an important treatment option for diabetes. This study examined whether Roux-en-Y gastric bypass surgery, a new metabolic bariatric surgery approach, can effectively reduce the risk of long-term renal impairment in individuals with type 2 diabetes. Methods: In a cohort study, 60 individuals suffering from both obesity and type 2 diabetes were stratified and randomly divided into 2 groups based on gender and weight. The control group (30 cases) received internal medicine treatment; the observation group (30 cases) received Roux-en-Y gastric bypass surgery. The study compared the changes in glycated hemoglobin, fasting blood glucose, fasting insulin, fasting C-peptide, postprandial 2-hour blood glucose, postprandial 2-hour insulin, postprandial 2-hour C-peptide, weight, waist circumference, and BMI before and at 6, 12, and 18 months after treatment. Kidney function-related indicators such as urinary protein excretion, microalbuminuria, and creatinine clearance were also compared. Results: There were no significant differences in the above indicators between the 2 groups before treatment (P > .05). After 6, 12, and 18 months of treatment, the levels of glycated hemoglobin, fasting blood glucose, fasting insulin, fasting C-peptide, postprandial 2-hour blood glucose, postprandial 2-hour insulin, postprandial 2-hour C-peptide, weight, waist circumference, and BMI were significantly decreased compared to before treatment (P < .05). Urinary protein excretion and microalbuminuria decreased, while creatinine clearance increased after 6, 12, and 18 months of surgery (P < .05). The differences in indicators between the 2 groups at each point after surgery were statistically significant (P < .05). Conclusion: Roux-en-Y gastric bypass surgery was more effective than medical treatment in treating type 2 diabetes and mitigating long-term kidney function damage. These findings confirm the clinical utility of Roux-en-Y gastric bypass surgery in these conditions, indicating its potential for generalization and reference.

9.
Curr Biol ; 34(11): 2359-2372.e9, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38692276

RESUMO

Host reproduction can be manipulated by bacterial symbionts in various ways. Parthenogenesis induction is the most effective type of reproduction manipulation by symbionts for their transmission. Insect sex is determined by regulation of doublesex (dsx) splicing through transformer2 (tra2) and transformer (tra) interaction. Although parthenogenesis induction by symbionts has been studied since the 1970s, its underlying molecular mechanism is unknown. Here we identify a Wolbachia parthenogenesis-induction feminization factor gene (piff) that targets sex-determining genes and causes female-producing parthenogenesis in the haplodiploid parasitoid Encarsia formosa. We found that Wolbachia elimination repressed expression of female-specific dsx and enhanced expression of male-specific dsx, which led to the production of wasp haploid male offspring. Furthermore, we found that E. formosa tra is truncated and non-functional, and Wolbachia has a functional tra homolog, termed piff, with an insect origin. Wolbachia PIFF can colocalize and interact with wasp TRA2. Moreover, Wolbachia piff has coordinated expression with tra2 and dsx of E. formosa. Our results demonstrate the bacterial symbiont Wolbachia has acquired an insect gene to manipulate the host sex determination cascade and induce parthenogenesis in wasps. This study reveals insect-to-bacteria horizontal gene transfer drives the evolution of animal sex determination systems, elucidating a striking mechanism of insect-microbe symbiosis.


Assuntos
Transferência Genética Horizontal , Simbiose , Vespas , Wolbachia , Animais , Wolbachia/fisiologia , Wolbachia/genética , Vespas/fisiologia , Vespas/microbiologia , Vespas/genética , Simbiose/genética , Feminino , Masculino , Partenogênese/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Processos de Determinação Sexual/genética
10.
J Am Chem Soc ; 146(19): 13000-13009, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38710503

RESUMO

Amphiphilic bottlebrush block copolymers (BBCPs), having a hydrophilic bottlebrush polymer (BP) linked covalently to a hydrophobic BP, were found to segregate to liquid-liquid interfaces to minimize the free energy of the system. The key parameter influencing the outcome of the experiments is the ratio between the degree of polymerization of the backbone (NBB) and that of the side-chain brushes (NSC). Specifically, a spherical, star-like configuration results when NBB < NSC, while a cylindrical, bottlebrush-like shape is preferred when NBB > NSC. Dynamic interfacial tension (γ) and fluorescence recovery after photobleaching (FRAP) measurements show that the BBCP configuration influences the areal density and in-plane diffusion at the fluid interface. The characteristic relaxation times associated with BBCP adsorption (τA) and reorganization (τR) were determined by fitting time-dependent interfacial tension measurements to a sum of two exponential relaxation functions. Both τA and τR initially increased with NBB up to 92 repeat units, due to the larger hydrodynamic radius in solution and slower in-plane diffusivity, attributed to a shorter cross-sectional diameter of the side-chains near the block junction. This trend reversed at NBB = 190, with shorter τA and τR attributed to increased segregation strength and exposure of the bare water/toluene interface due to tilting and/or wiggling of the backbone chains, respectively. The adsorption energy barrier decreased with higher NBB, due to a reduced BBCP packing density at the fluid interface. This study provides fundamental insights into macromolecular assembly at fluid interfaces, as it pertains to unique bottlebrush block architectures.

11.
Clin Transl Oncol ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777950

RESUMO

PURPOSE: The advent of circulating tumor DNA (ctDNA) technology has provided a convenient and noninvasive means to continuously monitor cancer genomic data, facilitating personalized cancer treatment. This study aimed to evaluate the supplementary benefits of plasma ctDNA alongside traditional tissue-based next-generation sequencing (NGS) in identifying targetable mutations and tumor mutational burden (TMB) in colorectal cancers (CRC). METHODS: Our study involved 76 CRC patients, collecting both tissue and plasma samples for NGS. We assessed the concordance of gene mutational status between ctDNA and tissue, focusing on actionable genes such as KRAS, NRAS, PIK3CA, BRAF, and ERBB2. Logistic regression analysis was used to explore variables associated with discordance and positive mutation rates. RESULTS: In total, 26 cancer-related genes were identified. The most common variants in tumor tissues and plasma samples were in APC (57.9% vs 19.7%), TP53 (55.3% vs 22.4%) and KRAS (47.4% vs 43.4%). Tissue and ctDNA showed an overall concordance of 73.53% in detecting actionable gene mutations. Notably, plasma ctDNA improved detection for certain genes and gene pools. Variables significantly associated with discordance included gender and peritoneal metastases. TMB analysis revealed a higher detection rate in tissues compared to plasma, but combining both increased detection. CONCLUSIONS: Our study highlights the importance of analyzing both tissue and plasma for detecting actionable mutations in CRC, with plasma ctDNA offering added value. Discordance is associated with gender and peritoneal metastases, and TMB analysis can benefit from a combination of tissue and plasma data. This approach provides valuable insights for personalized CRC treatment.

12.
Environ Sci Technol ; 58(14): 6296-6304, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38556999

RESUMO

Anaerobic digestion (AD) is an important biological resource recovery process, where microorganisms play key roles for material transformation. There has been some knowledge about the prokaryotic community and antibiotic resistance genes (ARGs) in AD, but there has been very limited knowledge of phages. In this study, samples from a full-scale AD plant were collected over 13 months, sequenced, and analyzed for viral and prokaryotic metagenomes. Totally, 3015 viral operational taxonomic units (vOTUs) were detected, mostly assigned to Caudoviricetes. The phage community had faster temporal variation than the prokaryotic community. Warm seasons harbored a higher abundance of both temperate phages and broad host-range phages. Seven ARGs of 6 subtypes were carried by 20 vOTUs, a representative ermT gene was synthesized and expressed, and the resistance activity in the host was examined, confirming the real activity of virus-carried ARGs in the AD process. Some of the ARGs were horizontally transferred between the phage and prokaryotic genomes. However, phage infection was not found to contribute to ARG transfer. This study provided an insight into the ecological patterns of the phage community, confirmed the antibiotic resistance activity of virus-carried ARGs, evaluated the contribution of phages on the ARG prevalence, and laid the foundation for the control strategies of the community and antibiotic resistance in the AD process.


Assuntos
Bacteriófagos , Esgotos , Bacteriófagos/genética , Antibacterianos/farmacologia , Anaerobiose , Prevalência , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos
13.
Small ; : e2401731, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38682736

RESUMO

Natural polyphenolic compounds play a vital role in nature and are widely utilized as building blocks in the fabrication of emerging functional nanomaterials. Although diverse fabrication methodologies are developed in recent years, the challenges of purification, uncontrollable reaction processes and additional additives persist. Herein, a modular and facile methodology is reported toward the fabrication of natural polyphenolic nanoparticles. By utilizing low frequency ultrasound (40 kHz), the assembly of various natural polyphenolic building blocks is successfully induced, allowing for precise control over the particle formation process. The resulting natural polyphenolic nanoparticles possessed excellent in vitro antioxidative abilities and in vivo therapeutic effects in typical oxidative stress models including wound healing and acute kidney injury. This study opens new avenues for the fabrication of functional materials from naturally occurring building blocks, offering promising prospects for future advancements in this field.

14.
J Phys Chem B ; 128(17): 4220-4230, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38648367

RESUMO

Star block copolymers (s-BCPs) have potential applications as novel surfactants or amphiphiles for emulsification, compatibilization, chemical transformations, and separations. s-BCPs have chain architectures where three or more linear diblock copolymer arms comprised of two chemically distinct linear polymers, e.g., solvophobic and solvophilic chains, are covalently joined at one point. The chemical composition of each of the subunit polymer chains comprising the arms, their molecular weights, and the number of arms can be varied to tailor the surface and interfacial activity of these architecturally unique molecules. This makes identification of the optimal s-BCP design nontrivial as the total number of plausible s-BCP architectures is experimentally or computationally intractable. In this work, we use molecular dynamics (MD) simulations coupled with a reinforcement learning-based Monte Carlo tree search (MCTS) to identify s-BCP designs that minimize the interfacial tension between polar and nonpolar solvents. We first validate the MCTS approach for the design of small- and medium-sized s-BCPs and then use it to efficiently identify sequences of copolymer blocks for large-sized s-BCPs. The structural origins of interfacial tension in these systems are also identified by using the configurations obtained from MD simulations. Chemical insights into the arrangement of copolymer blocks that promote lower interfacial tension were mined using machine learning (ML) techniques. Overall, this work provides an efficient approach to solve design problems via fusion of simulations and ML and provides important groundwork for future experimental investigation of s-BCPs for various applications.

15.
Langmuir ; 40(18): 9345-9361, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38669686

RESUMO

Poly(dimethylsiloxane) (PDMS) has numerous excellent properties and is extensively used as the main component of many silicone products in a variety of research fields and practical applications such as biomedical materials, aviation, construction, electronic devices, and automobiles. Interfacial structures of PDMS and other components in silicone systems are important for such research and applications. It is difficult to probe interfacial molecular structures of buried solid-liquid and solid-solid interfaces of silicone materials due to the lack of appropriate analytical tools. In this feature article, we presented our research on elucidating the molecular structures of PDMS as well as other additives in silicone samples at buried interfaces in situ at the molecular level using a nonlinear optical spectroscopic technique, sum frequency generation (SFG) vibrational spectroscopy. SFG was applied to study various PDMS surfaces in liquid environments to understand their fouling-release and antifouling activities. SFG has also been used to study buried solid-solid interfaces between silicone adhesives and polymers, elucidating the molecular adhesion mechanisms. Our SFG studies provide important knowledge on interfacial structure-function relationships of silicone materials, helping the design and development of silicone materials with improved properties through optimization of silicone interfacial structures.

16.
Sensors (Basel) ; 24(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38676031

RESUMO

The various applications of bearing-only sensor networks for detection and localization are becoming increasingly widespread and important. The array layout of the bearing-only sensor network seriously impacts the detection performance. This paper proposes a multi-strategy fusion improved adaptive mayfly algorithm (MIAMA) in a bearing-only sensor network to perform layout planning on the geometric configuration of the optimal detection. Firstly, the system model of a bearing-only sensor network was constructed, and the observability of the system was analyzed based on the Cramer-Rao Lower Bound and Fisher Information Matrix. Then, in view of the limitations of the traditional mayfly algorithm, which has a single initial population and no adaptability and poor global search capabilities, multi-strategy fusion improvements were carried out by introducing Tent chaos mapping, the adaptive inertia weight factor, and Random Opposition-based Learning. Finally, three simulation experiments were conducted. Through comparison with the Particle Swarm Optimization (PSO) algorithm, Mayfly Algorithm (MA), and Genetic Algorithm (GA), the effectiveness and superiority of the proposed MIAMA were validated.

17.
EMBO J ; 43(8): 1519-1544, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38528180

RESUMO

Pericytes and endothelial cells (ECs) constitute the fundamental components of blood vessels. While the role of ECs in tumor angiogenesis and the tumor microenvironment is well appreciated, pericyte function in tumors remains underexplored. In this study, we used pericyte-specific deletion of the nitric oxide (NO) receptor, soluble guanylate cyclase (sGC), to investigate via single-cell RNA sequencing how pericytes influence the vascular niche and the tumor microenvironment. Our findings demonstrate that pericyte sGC deletion disrupts EC-pericyte interactions, impairing Notch-mediated intercellular communication and triggering extensive transcriptomic reprogramming in both pericytes and ECs. These changes further extended their influence to neighboring cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs) through paracrine signaling, collectively suppressing tumor growth. Inhibition of pericyte sGC has minimal impact on quiescent vessels but significantly increases the vulnerability of angiogenic tumor vessels to conventional anti-angiogenic therapy. In conclusion, our findings elucidate the role of pericytes in shaping the tumor vascular niche and tumor microenvironment and support pericyte sGC targeting as a promising strategy for improving anti-angiogenic therapy for cancer treatment.


Assuntos
Neoplasias , Pericitos , Humanos , Pericitos/patologia , Pericitos/fisiologia , Guanilil Ciclase Solúvel , Células Endoteliais/fisiologia , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neoplasias/genética , Neoplasias/patologia , Guanilato Ciclase , Microambiente Tumoral
18.
Adv Sci (Weinh) ; 11(19): e2306850, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38477543

RESUMO

Micro-Doppler effect is a vital feature of a target that reflects its oscillatory motions apart from bulk motion and provides an important evidence for target recognition with radars. However, establishing the micro-Doppler database poses a great challenge, since plenty of experiments are required to get the micro-Doppler signatures of different targets for the purpose of analyses and interpretations with radars, which are dramatically limited by high cost and time-consuming. Aiming to overcome these limits, a low-cost and powerful simulation platform of the micro-Doppler effects is proposed based on time-domain digital coding metasurface (TDCM). Owing to the outstanding capabilities of TDCM in generating and manipulating nonlinear harmonics during wave-matter interactions, it enables to supply rich and high-precision electromagnetic signals with multiple micro-Doppler frequencies to describe the micro-motions of different objects, which are especially favored for the training of artificial intelligence algorithms in automatic target recognition and benefit a host of applications like imaging and biosensing.

19.
Discov Med ; 36(182): 527-537, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38531793

RESUMO

BACKGROUND: The clinical outcomes of chemotherapy (CT) for the treatment of metastatic triple-negative (TN) and hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (mBC) have proven to be disappointing. The phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway, a tumor-promoting signaling cascade frequently mutated in breast cancer (BC), has been implicated in chemoresistance. In this study, our objective is to investigate the efficacy and safety of combining everolimus with chemotherapy in mBC patients exhibiting mutations in the PI3K/AKT/mTOR pathway. METHODS: We conducted a retrospective analysis to characterize the efficacy, safety, and their association with clinical and molecular characteristics of metastatic lesions in 14 patients with HER2- mBC. These patients harbored at least one altered member of the PI3K/AKT/mTOR signaling pathway and were treated with a combination of a chemotherapy agent and the mTOR inhibitor everolimus (CT+EVE). RESULTS: The majority of patients belonged to the triple-negative (TN) subtype (9/14, 64.3%), having already undergone 2 lines of chemotherapy (CT) in the metastatic setting (11, 78.6%). These patients carried altered phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) and were administered a vinorelbine-containing regimen (10, 71.4%). The objective response rate (ORR) was 42.9%, with a disease control rate of 92.9%. The median progression-free survival (PFS) and overall survival (OS) were 5.9 (95% confidence interval (CI): 4.9-13.6) months and 14.3 (95% CI: 8.5-not reached (NR)) months, respectively. Patients with fewer prior treatment lines tended to exhibit longer PFS. OS, PFS, and ORR were comparable between hormone receptor-positive (HR+) and triple-negative breast cancer (TNBC) patients, but numerical improvements were noted in patients with a single PI3K pathway alteration compared to those with more than one alteration. Genomic alterations that surfaced upon progression on CT+EVE included cyclin dependent kinase 4 (CDK4) and epidermal growth factor receptor (EGFR) amplification, as well as neurofibromin 1 (NF1) mutation, suggesting potential mechanisms of acquired resistance. An analysis of adverse events indicated manageable toxicities. CONCLUSIONS: The findings of this study suggest both activity and safety for the combination of chemotherapy and the mTOR inhibitor everolimus (CT+EVE) in patients with HER2- mBC who have alterations in the PI3K pathway, particularly those who have received fewer prior chemotherapy. However, it is crucial to note that large-scale, randomized control studies are warranted to more comprehensively characterize the efficacy and safety of this combination therapy.


Assuntos
Neoplasias da Mama , Everolimo , Humanos , Feminino , Everolimo/uso terapêutico , Neoplasias da Mama/patologia , Proteínas Proto-Oncogênicas c-akt/uso terapêutico , Fosfatidilinositol 3-Quinases , Estudos Retrospectivos , Receptor ErbB-2/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Serina-Treonina Quinases TOR
20.
Entropy (Basel) ; 26(3)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38539748

RESUMO

The problem of state estimation based on bearing-only sensors is increasingly important while existing research on distributed filtering solutions is rather limited. Therefore, this paper proposed the novel distributed cubature information filtering (DCIF) method for addressing the state estimation challenge in bearing-only sensor networks. Firstly, the system model of the bearing-only sensor network was constructed, and the observability of the system was analyzed. The sensor nodes are paired to measure relative angle information. Subsequently, the coordinated consistency theory is employed to achieve a unified state estimation of the maneuvering target. The DCIF method enhances the observability of the system, addressing the issues of large accuracy errors and divergence in traditional nonlinear filtering algorithms. Building upon the theoretical proof of consistency convergence in DCIF, four simulation experiments were conducted for comparison. These experiments validate the effectiveness and superiority of the DCIF method in bearing-only sensor networks.

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