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1.
Br J Cancer ; 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38643337

RESUMEN

The World Health Organisation recognised human papillomavirus (HPV) as the cause of multiple cancers, including head and neck cancers. HPV is a double-stranded DNA virus, and its viral gene expression can be controlled after infection by cellular and viral promoters. In cancer cells, the HPV genome is detected as either integrated into the host genome, episomal (extrachromosomal), or a mixture of integrated and episomal. Viral integration requires the breakage of both viral and host DNA, and the integration rate correlates with the level of DNA damage. Interestingly, patients with HPV-positive head and neck cancers generally have a good prognosis except for a group of patients with fully integrated HPV who show worst clinical outcomes. Those patients present with lowered expression of viral genes and limited infiltration of cytotoxic T cells. An impediment to effective therapy applications in the clinic is the sole testing for HPV positivity without considering the HPV integration status. This review will discuss HPV integration as a potential determinant of response to therapies in head and neck cancers and highlight to the field a novel therapeutic avenue that would reduce the cancer burden and improve patient survival.

2.
BMC Cancer ; 24(1): 313, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448829

RESUMEN

BACKGROUND: Transversal approach for robotic-assisted radical prostatectomy via a bladder neck and prostate combined longitudinal incision (L-RALP) is a novel surgical method for patients with respectable prostate cancer. METHODS: There were 669 patients with prostate cancer underwent L-RALP or S-RALP which identified from April 2016 to April 2020. The perioperative outcomes, Expanded Prostate Cancer Index Composite for Clinical Practice (EPIC-CP) scores, sexual function and urinary control ability were included and compared between two groups. RESULTS: In the 669 patients, 277 of them were included into the final analysis. 151 patients received S-RALP and 126 received L-RALP. Baseline features were balanced. Patients in the S-RALP group had significantly shorter average surgical time (135.93 vs 150.04 min; p < 0.001) than those in L-RALP group. Intraoperative bleeding volume, early postoperative complications rates, postoperative catheter removal time and hospital stays were comparable between two groups. There was no difference in biochemical recurrence at 3, 6, 12 and 18 months of follow-up. Of note, the urinary control function recovers of patients in the L-RALP group was significantly better than those in the S-RALP group. Moreover, patients in the L-RALP group had much better results of EPIC-CP (including urinary control and total score) than those in the S-RALP group at 6 week and 3, 6, 12 and 18 months. CONCLUSIONS: Both S-RALP and L-RALP were safe and effective with similar long-term clinical outcomes in patients with respectable prostate cancer. Patients received L-RALP had significantly better postoperative outcomes including urinary control, and recovery period.


Asunto(s)
Neoplasias de la Próstata , Procedimientos Quirúrgicos Robotizados , Herida Quirúrgica , Masculino , Humanos , Próstata , Vejiga Urinaria/cirugía , Procedimientos Quirúrgicos Robotizados/efectos adversos , Estudios Retrospectivos , Neoplasias de la Próstata/cirugía , Prostatectomía
3.
Anal Chem ; 95(39): 14665-14674, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37679861

RESUMEN

A sandwich immunoassay theoretically exhibits higher sensitivity and specificity compared to a competitive counterpart; however, it is extremely difficult to obtain a pair of antibodies that can bind to a small molecule simultaneously, which is always thought to be a single epitope. In the present study, abamectin (ABM) was selected to prove the effect of hapten design and antibody recognition properties on the development of a sandwich immunoassay for small molecules. First, the epitopes of ABM were roughly located, and epitope distances were determined. Then, two haptens were designed by introducing spacer arms at the C4″-OH and C5-OH of ABM, respectively, aiming to provide the longest epitope distances. A total of seven rabbit polyclonal antibodies (pAbs) and 21 mouse monoclonal antibodies (mAbs) with various recognition properties were obtained. Extensive combinatorial associations of antibody pairs for simultaneously binding to ABM were performed, and only two mAb-mAb pairs were observed to achieve a sandwich immunoassay for ABM with a total success rate of 0.27%. The best mAb pair for sandwich immunoassay was confirmed by surface plasmon resonance, used to develop a sandwich immunoassay, and then evaluated by cross-reactivities and molecular docking with structurally similar analogues and abamectin. Altogether, the study provided a theoretical foundation as well as practical experience and demonstrated the importance of careful hapten design and extensive antibody screening to successfully establish the sandwich immunoassay for small molecules.


Asunto(s)
Anticuerpos Monoclonales , Haptenos , Animales , Ratones , Conejos , Simulación del Acoplamiento Molecular , Anticuerpos Monoclonales/química , Inmunoensayo , Epítopos , Ensayo de Inmunoadsorción Enzimática
4.
Anal Chem ; 95(12): 5223-5231, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36920169

RESUMEN

Aggregation-induced emission luminogens (AIEgens) are promising candidates for bacterial imaging and detection because they can "Light-Up" pathogenic bacteria without complicated labeling or washing steps. However, there have been few in-depth analyses of the intrinsic mechanism underlying their utility as fluorescence probes for targeting bacteria. Therefore, using large-scale molecular dynamics simulations, we investigated the mechanism of their bacterial "Light-Up" behavior with N,N-diphenyl-4-(7-(pyridin-4-yl)benzo[c][1,2,5]thiadiazol-4-yl) aniline functionalized with 1-bromoethane (TBP-1). We propose that the triphenylamine motif of TBP-1, rather than the positively charged pyridine group, first contacts the cell membrane. After TBP-1 completely inserts into the cell membrane, the hydrophobic triphenylamine motif localizes in the hydrophobic core of the cell membrane, restricting the molecular variation of TBP-1, which induces the fluorescent "turn-on" and bacterial "Light-Up." On this basis, we established a heterogeneous lateral flow immunoassay (LFIA) for the detection of foodborne pathogens. The LFIA system showed improved sensitivity with a limit of detection as low as 103 CFU mL-1 and strong specificity. Our protocol opened an effective shortcut to the design of more efficient AIEgens and novel AIEgens-based immunoassays.


Asunto(s)
Técnicas Biosensibles , Colorantes Fluorescentes/química , Inmunoensayo , Diagnóstico por Imagen , Bacterias
5.
Molecules ; 28(12)2023 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-37375244

RESUMEN

Pretreatment of sugarcane bagasse (SCB) by aqueous acetic acid (AA), with the addition of sulfuric acid (SA) as a catalyst under mild condition (<110 °C), was investigated. A response surface methodology (central composite design) was employed to study the effects of temperature, AA concentration, time, and SA concentration, as well as their interactive effects, on several response variables. Kinetic modeling was further investigated for AA pretreatment using both Saeman's model and the Potential Degree of Reaction (PDR) model. It was found that Saeman's model showed a great deviation from the experimental results, while the PDR model fitted the experimental data very well, with determination coefficients of 0.95-0.99. However, poor enzymatic digestibility of the AA-pretreated substrates was observed, mainly due to the relatively low degree of delignification and acetylation of cellulose. Post-treatment of the pretreated cellulosic solid well improved the cellulose digestibly by further selectively removing 50-60% of the residual linin and acetyl group. The enzymatic polysaccharide conversion increased from <30% for AA-pretreatment to about 70% for PAA post-treatment.


Asunto(s)
Celulosa , Saccharum , Ácido Peracético/farmacología , Ácido Acético , Hidrólisis , Lignina
6.
Molecules ; 28(17)2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37687222

RESUMEN

With population and economic development increasing worldwide, the public is increasingly concerned with the health benefits and nutritional properties of vegetable oils (VOs). In this review, the chemical composition and health-promoting benefits of 39 kinds of VOs were selected and summarized using Web of Science TM as the main bibliographic databases. The characteristic chemical compositions were analyzed from fatty acid composition, tocols, phytosterols, squalene, carotenoids, phenolics, and phospholipids. Health benefits including antioxidant activity, prevention of cardiovascular disease (CVD), anti-inflammatory, anti-obesity, anti-cancer, diabetes treatment, and kidney and liver protection were examined according to the key components in representative VOs. Every type of vegetable oil has shown its own unique chemical composition with significant variation in each key component and thereby illustrated their own specific advantages and health effects. Therefore, different types of VOs can be selected to meet individual needs accordingly. For example, to prevent CVD, more unsaturated fatty acids and phytosterols should be supplied by consuming pomegranate seed oil, flaxseed oil, or rice bran oil, while coconut oil or perilla seed oil have higher contents of total phenolics and might be better choices for diabetics. Several oils such as olive oil, corn oil, cress oil, and rice bran oil were recommended for their abundant nutritional ingredients, but the intake of only one type of vegetable oil might have drawbacks. This review increases the comprehensive understanding of the correlation between health effects and the characteristic composition of VOs, and provides future trends towards their utilization for the general public's nutrition, balanced diet, and as a reference for disease prevention. Nevertheless, some VOs are in the early stages of research and lack enough reliable data and long-term or large consumption information of the effect on the human body, therefore further investigations will be needed for their health benefits.


Asunto(s)
Enfermedades Cardiovasculares , Aceites de Plantas , Humanos , Aceite de Salvado de Arroz , Aceite de Maíz , Aceite de Coco , Enfermedades Cardiovasculares/prevención & control
7.
Anal Chem ; 94(51): 17843-17852, 2022 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-36519948

RESUMEN

The pursuit of the limit between dimensionalities is a scientific goal with high applicability. Sandwich immunoassay, usually based on two antibodies binding two epitopes, is one of the most popular mainstay tools in both academic and industrial fields. Herein, we determined and evaluated the minimum distance of two epitopes in sandwich immunoassays for small molecules. Briefly, nine model analytes comprising two hapten epitopes, that is, melamine (MEL) and p-nitroaniline (NIA), were designed by increasing the linear chain linkers brick by brick. Two groups of monoclonal antibodies (mAbs) were produced with different recognition properties toward MEL and NIA using 12 new haptens with different spacer arms. The results indicated that two epitopes of the analyte with a distance of only 2.4 Å could be simultaneously bound by two mAbs, which is the known limit of epitope distance in sandwich immunoassays thus far. We further found that an epitope distance of below 8.8 Å for the analyte generally induces noticeable steric hindrance of antibodies, preventing a sandwich immunoassay with high probability. These observations were investigated and evaluated by molecular docking, molecular dynamics, and surface plasmon resonance and using model and real analytes. Altogether, we determined the minimum distance of two epitopes and explored the molecular mechanism of the antibody-analyte-antibody ternary complex in sandwich immunoassays, providing a theoretical basis for hapten design, antibody discovery and development, and sandwich immunoassay establishment for small molecules.


Asunto(s)
Anticuerpos Monoclonales , Haptenos , Epítopos , Simulación del Acoplamiento Molecular , Inmunoensayo/métodos , Anticuerpos Monoclonales/química
8.
Mol Ther ; 29(8): 2571-2582, 2021 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-33775911

RESUMEN

Current therapies for treating heterogeneous cancers such as head and neck squamous cell carcinoma (HNSCC) are non-selective and are administered independent of response biomarkers. Therapy resistance subsequently emerges, resulting in increased cellular proliferation that is associated with loss of differentiation. Whether a cancer cell differentiation potential can dictate therapy responsiveness is still currently unknown. A multi-omic approach integrating whole-genome and whole-transcriptome sequencing with drug sensitivity was employed in a HNSCC mouse model, primary patients' data, and human cell lines to assess the potential of functional differentiation in predicting therapy response. Interestingly, a subset of HNSCC with effective GRHL3-dependent differentiation was the most sensitive to inhibitors of PI3K/mTOR, c-Myc, and STAT3 signaling. Furthermore, we identified the GRHL3-differentiation target gene Filaggrin (FLG) as a response biomarker and more importantly, stratified HNSCC subsets as treatment resistant based on their FLG mutational profile. The loss of FLG in sensitive HNSCC resulted in a dramatic resistance to targeted therapies while the GRHL3-FLG signature predicted a favorable patient prognosis. This study provides evidence for a functional GRHL3-FLG tumor-specific differentiation axis that regulates targeted therapy response in HNSCC and establishes a rationale for clinical investigation of differentiation-paired targeted therapy in heterogeneous cancers.


Asunto(s)
Biomarcadores de Tumor/genética , Proteínas de Unión al ADN/genética , Proteínas Filagrina/genética , Neoplasias de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Factores de Transcripción/genética , Animales , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Trasplante de Neoplasias , Pronóstico , Transducción de Señal , Secuenciación del Exoma , Secuenciación Completa del Genoma
9.
BMC Cancer ; 21(1): 814, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-34266404

RESUMEN

BACKGROUND: The molecular prognostic biomarkers of clear cell renal cell carcinoma (ccRCC) are still unknown. We aimed at researching the candidate biomarkers and potential therapeutic targets of ccRCC. METHODS: Three ccRCC expression microarray datasets (include GSE14762, GSE66270 and GSE53757) were downloaded from the gene expression omnibus (GEO) database. The differentially expressed genes (DEGs) between ccRCC and normal tissues were explored. The potential functions of identified DEGs were analyzed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). And then the protein - protein interaction network (PPI) was established to screen the hub genes. After that, the expressions of hub genes were identified by the oncomine database. The hub genes' prognostic values of patients with ccRCC were analyzed by GEPIA database. RESULTS: A total of 137 DEGs were identified by utilizing the limma package and RRA method, including 63 upregulated genes and 74 downregulated genes. It is found that 137 DEGs were mainly enriched in 82 functional terms and 24 pathways in accordance with the research results. Thirteen highest-scoring genes were screened as hub genes (include 10 upregulated genes and 3 downregulated candidate genes) by utilizing the PPI network and module analysis. Through integrating the oncoming database and GEPIA database, the author found that C3 and CXCR4 are not only overexpressed in ccRCC, but also associated with the prognosis of ccRCC. Further results could reveal that patients with high C3 expression had a poor overall survival (OS), while patients with high CTSS and TLR3 expressions had a good OS; patients with high C3 and CXCR4 expressions had a poor disease-free survival (DFS), while ccRCC patients with high TLR3 expression had a good DFS. CONCLUSION: These findings suggested that C3 and CXCR4 were the candidate biomarkers and potential therapeutic targets of ccRCC patients.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Renales/genética , Complemento C3/metabolismo , Biología Computacional/métodos , Neoplasias Renales/genética , Receptores CXCR4/metabolismo , Carcinoma de Células Renales/patología , Humanos , Neoplasias Renales/patología , Pronóstico
10.
Anal Bioanal Chem ; 413(20): 4979-4987, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34240228

RESUMEN

Phallotoxins, toxic cyclopeptides found in wild poisonous mushrooms, are predominant causes of fatal food poisoning. For the early and rapid diagnosis mushroom toxin poisoning, a highly sensitive and robust monoclonal antibody (mAb) against phallotoxins was produced for the first time. The half-maximum inhibition concentration (IC50) values of the mAb-based indirect competitive ELISAs for phallacidin (PCD) and phalloidin (PHD) detection were 0.31 ng mL-1 and 0.35 ng mL-1, respectively. In response to the demand for rapid screening of the type of poisoning and accurate determination of the severity of poisoning, colloidal gold nanoparticle (GNP) and time-resolved fluorescent nanosphere (TRFN) based lateral flow assays (LFA) were developed. The GNP-LFA has a visual cut-off value of 3.0 ng mL-1 for phallotoxins in human urine sample. The TRFN-LFA provides a quantitative readout signal with detection limit of 0.1 ng mL-1 in human urine sample. In this study, urine samples without pretreatment were used directly for the LFA strip tests, and both two LFAs were able to accomplish analysis within 10 min. The results demonstrated that LFAs based on the newly produced, highly sensitive, and robust mAb were able to be used for both rapid qualitative screening of the type of poisoning and accurate quantitative determination of the severity of poisoning after accidental ingestion by patients of toxic mushrooms.


Asunto(s)
Amanitinas/química , Amanitinas/orina , Anticuerpos Monoclonales/química , Tiras Reactivas , Animales , Oro/química , Humanos , Límite de Detección , Nanopartículas del Metal/química , Ratones , Estructura Molecular , Intoxicación por Setas/diagnóstico , Intoxicación por Setas/orina , Sensibilidad y Especificidad
11.
BMC Surg ; 21(1): 388, 2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34727908

RESUMEN

BACKGROUND: With the development of minimally invasive surgery technology, patients with bladder cancer are increasingly receiving laparoscopic radical cystectomy (LRC) or robotic-assisted radical cystectomy (RARC) treatment. The main purpose of this study was to compare the long-term outcomes of bladder cancer patients treated with LRC versus RARC. METHODS: A retrospective study to identify patients with clinical stage Ta/T1/Tis to T3 bladder cancer who underwent RARC or LRC has been performed. The perioperative outcome, recurrence, and overall survival (OS) of the two surgical methods were compared. RESULTS: 218 patients were identified from March 2010 to December 2019 in our department, which including 82 (38%) patients who received LRC and 136 (62%) patients who received RARC. There was no significant difference between the two groups in terms of lymph node collection, lymph node positive rate, resection margin positive rate, and postoperative pathological staging. Compared with the LRC group, patients in the RARC group had a median estimated blood loss (180 vs. 250 ml; P = 0.02) and reduced complications at 90 days postoperatively (30.8% vs. 46.3%; P = 0.01). Recurrence, all-cause death, and cancer-specific death occurred in 77 (35%), 55 (25%), and 39 (18%) patients, respectively. The 5-year OS rate was 54.63% and 54.65% in the RARC and LRC group (P > 0.05). The 5-year cancer-specific survival (CSS) rate was 73.32% and 61.55% in RARC and LRC group (P > 0.05). There was no significant difference in OS [hazard ratio (HR) 1.083, 95% confidence interval (CI) 0.626-1.874; P = 0.78], and CSS (HR 0.789, 95%CI 0.411-1.515; P = 0.61) between two groups. CONCLUSIONS: Both RARC and LRC were safe and effective with a similar long-term clinical outcomes. Moreover, RARC had significantly lower median estimated blood loss and reduced postoperative complications.


Asunto(s)
Laparoscopía , Procedimientos Quirúrgicos Robotizados , Robótica , Neoplasias de la Vejiga Urinaria , Cistectomía , Humanos , Recurrencia Local de Neoplasia/epidemiología , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/cirugía
12.
Molecules ; 26(18)2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34577037

RESUMEN

Theoretically, sandwich immunoassay is more sensitive and has a wider working range than that of competitive format. However, it has been thought that small molecules cannot be detected by the sandwich format due to their limited size. In the present study, we proposed a novel strategy for achieving sandwich immunoassay of ß-lactams with low molecular weights. Firstly, five ß-lactam antibiotics were selected to bind with penicillin binding protein (PBP)2x* to form complexes. Then, monoclonal and polyclonal antibodies against PBP2x*-ß-lactams complexes were produced by animal immunization. Subsequently, the optimal pairing antibodies were utilized to establish sandwich immunoassay for detection of 18 PBP2x*-ß-lactam complexes. Among them, ceftriaxone could be detected at as low as 1.65 ng/mL with working range of 1-1000 ng/mL in milk. To reveal the detection mechanism, computational chemistry and molecular recognition study were carried out. The results showed that ß-lactams with a large size and complex structures maybe conducive to induce conformational changes of PBP2x*, and then exhibit greater possibility of being detected by sandwich immunoassay after combination with PBP2x*. This study provides insights for subsequent investigations of anti-metatype antibody screening and sandwich immunoassay establishment for small-molecule detection.


Asunto(s)
Proteínas de Unión a las Penicilinas , Streptococcus pneumoniae , beta-Lactamas , Antibacterianos , Pruebas de Sensibilidad Microbiana
13.
J Neuroinflammation ; 15(1): 153, 2018 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-29788964

RESUMEN

BACKGROUND: Microglia play key roles in neuron-glia interaction, neuroinflammation, neural repair, and neurotoxicity. Currently, various microglial in vitro models including primary microglia derived from distinct isolation methods and immortalized microglial cell lines are extensively used. However, the diversity of these existing models raises difficulty in parallel comparison across studies since microglia are sensitive to environmental changes, and thus, different models are likely to show widely varied responses to the same stimuli. To better understand the involvement of microglia in pathophysiological situations, it is critical to establish a reliable microglial model system. METHODS: With postnatal mouse brains, we isolated microglia using three general methods including shaking, mild trypsinization, and CD11b magnetic-associated cell sorting (MACS) and applied RNA sequencing to compare transcriptomes of the isolated cells. Additionally, we generated a genome-wide dataset by RNA sequencing of immortalized BV2 microglial cell line to compare with primary microglia. Furthermore, based on the outcomes of transcriptional analysis, we compared cellular functions between primary microglia and BV2 cells including immune responses to LPS by quantitative RT-PCR and Luminex Multiplex Assay, TGFß signaling probed by Western blot, and direct migration by chemotaxis assay. RESULTS: We found that although the yield and purity of microglia were comparable among the three isolation methods, mild trypsinization drove microglia in a relatively active state, evidenced by high amount of amoeboid microglia, enhanced expression of microglial activation genes, and suppression of microglial quiescent genes. In contrast, CD11b MACS was the most reliable and consistent method, and microglia isolated by this method maintained a relatively resting state. Transcriptional and functional analyses revealed that as compared to primary microglia, BV2 cells remain most of the immune functions such as responses to LPS but showed limited TGFß signaling and chemotaxis upon chemoattractant C5a. CONCLUSIONS: Collectively, we determined the optimal isolation methods for quiescent microglia and characterized the limitations of BV2 cells as an alternative of primary microglia. Considering transcriptional and functional differences, caution should be taken when extrapolating data from various microglial models. In addition, our RNA sequencing database serves as a valuable resource to provide novel insights for appropriate application of microglia as in vitro models.


Asunto(s)
Antígeno CD11b/metabolismo , Microglía/metabolismo , Análisis de Secuencia de ARN/métodos , Animales , Animales Recién Nacidos , Encéfalo/citología , Antígeno CD11b/genética , Ciclo Celular/efectos de los fármacos , Separación Celular/instrumentación , Células Cultivadas , Quimiotaxis , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Expresión Génica , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Lipopolisacáridos/farmacología , Ratones , Ratones Endogámicos C57BL , Microglía/efectos de los fármacos , Receptores de GABA/genética , Receptores de GABA/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Transcriptoma/fisiología , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Tripsina/farmacología
14.
Materials (Basel) ; 17(9)2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38730943

RESUMEN

In this study, the CALPHAD approach was employed to model the thermodynamics of the Au-Ge-X (X = In, Sb, Si, Zn) ternary systems, leveraging experimental phase equilibria data and previous assessments of related binary subsystems. The solution phases were modeled as substitutional solutions, and their excess Gibbs energies were expressed using the Redlich-Kister polynomial. Owing to the unavailability of experimental data, the solubility of the third elements in the Au-In, Au-Sb, and Au-Zn binary intermetallic compounds was excluded from consideration. Additionally, stable ternary intermetallic compounds were not reported in the literature and, thus, were not taken into account in the present thermodynamic calculations. Calculations of liquidus projections, isothermal sections, and vertical sections for these ternary systems have been performed, aligning with existing experimental findings. These thermodynamic parameters form a vital basis for creating a comprehensive thermodynamic database for Au-Ge-based alloys, which is essential for the design and development of new high-temperature Pb-free solders.

15.
Nat Commun ; 15(1): 666, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38253587

RESUMEN

Keen desires for artificial mimicry of biological polymers and property improvement of synthesized ones have triggered intensive explorations for sequence-controlled copolymerization. However, conventional synthesis faces great challenges to achieve this goal due to the strict requirements on reaction kinetics of comonomer pairs and tedious synthetic processes. Here, sequence-controlled alternating copolymerization with molecular precision is realized on surface. The stoichiometric control serves as a thermodynamic strategy to steer the polymerization selectivity, which enables the selective alternating organometallic copolymerization via intermolecular metalation of 4,4"-dibromo-p-terphenyl (P-Br) and 2,5-diethynyl-1,4-bis(phenylethynyl)benzene (A-H) with Ag adatoms on Ag(111) at P-Br: A-H = 2, as verified by scanning tunneling microscopy and density functional theory studies. In contrast, homopolymerization yield increases as the stoichiometric ratio deviates from 2. The microscopic characterizations rationalize the mechanism, providing a delicate explanation of the stoichiometry-dependent polymerization. These findings pave a way to actualizing an efficient sequence control of copolymerization by surface chemistry.

16.
J Agric Food Chem ; 72(6): 3160-3170, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38197248

RESUMEN

Flunixin (FLU) is a nonsteroidal drug that is widely used in animals, causing severe drug residues in animal-derived foods and environment. The development of antibody-based rapid immunoassay methods is of great significance for the monitoring of FLU and its metabolite 5-hydroxyflunixin (5-FLU). We prepared monoclonal antibodies (mAbs) with different recognition spectra through FLU-keyhole limpet hemocyanin conjugates as immunogen coupled with antibody screening strategies. mAb5E6 and mAb6D7 recognized FLU with high affinity, and mAb2H5 and mAb4A4 recognized FLU and 5-FLU with broad specificity. Through evaluating the recognition of these mAbs against more than 11 structural analogues and employing computational chemistry, molecular docking, and molecular dynamics methodologies, we preliminarily determined the recognition epitope and recognition mechanism of these mAbs. Finally, an indirect competitive enzyme-linked immunosorbent assay for FLU based on mAb6D7 was developed, which exhibited limits of detection as low as 0.016-0.042 µg kg -1 (L-1) in milk and muscle samples.


Asunto(s)
Anticuerpos Monoclonales , Formación de Anticuerpos , Clonixina/análogos & derivados , Animales , Simulación del Acoplamiento Molecular , Inmunoensayo , Ensayo de Inmunoadsorción Enzimática/métodos , Especificidad de Anticuerpos
17.
Aging (Albany NY) ; 16(2): 1696-1711, 2024 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-38261736

RESUMEN

OBJECTIVE: This study aims to establish an effective predictive model for predicting Xp11.2 translocation/TFE3 gene fusion renal cell carcinoma (TFE3-RCC) and develop optimal therapeutic strategies. METHODS: Data from 4961 patients diagnosed with renal cell carcinoma at two medical centers in China were retrospectively analyzed. A cohort of 1571 patients from Zhejiang Provincial People's Hospital (Ra cohort) was selected to construct the model. Another cohort of 1124 patients from the Second Affiliated Hospital of Zhejiang Chinese Medical University was used for external validation (the Ha cohort). All patients with TFE3-RCC in both cohorts were included in the Ta cohort for the prognostic analysis. Univariate and multivariate binary logistic regression analyses were performed to identify independent predictors of the predictive nomogram. The apparent performance of the model was validated. Decision curve analysis was also performed to assess the clinical utility of the developed model. Factors associated with progression and prognosis in the Ta cohort were analyzed using the log-rank method, and Cox regression analysis and Kaplan-Meier survival curves were used to describe the effects of factors on prognosis and progression. RESULTS: Univariate and multivariate logistic regression analyses demonstrated that age, sex, BMI, smoking, eosinophils, and LDL were independent predictors of TFE3-RCC. Therefore, a predictive nomogram for TFE3-RCC, which had good discriminatory power (AUC = 0.796), was constructed. External validation (AUC = 0.806) also revealed good predictive ability. The calibration curves displayed good consistency between the predicted and observed incidences of TFE3-RCC. Invasion of regional lymph nodes, tyrosine kinase inhibitors, and surgical methods were independent factors associated with progression. Tyrosine kinase inhibitors are independent prognostic factors. CONCLUSION: This study not only proposed a high-precision clinical prediction model composed of various variables for the early diagnosis of Xp11.2 translocation/TFE3 gene fusion renal cell carcinoma but also optimized therapeutic strategies through prognostic analysis.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/patología , Neoplasias Renales/genética , Neoplasias Renales/patología , Estudios Retrospectivos , Modelos Estadísticos , Translocación Genética , Pronóstico , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Cromosomas Humanos X/genética , Fusión Génica
18.
Nat Genet ; 33(2): 187-91, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12539046

RESUMEN

The female gamete (the oocyte) serves the distinct purpose of transmitting the maternal genome and other maternal factors that are critical for post-ovulation events. Through the identification and characterization of oocyte-specific factors, we are beginning to appreciate the diverse functions of oocytes in ovarian folliculogenesis, fertilization and embryogenesis. To understand these processes further, we identified genes called zygote arrest 1 (Zar1 and ZAR1 in mouse and human, respectively) as novel oocyte-specific genes. These encode proteins of 361 amino acids and 424 amino acids, respectively, which share 59% amino-acid identity and an atypical plant homeo-domain (PHD) motif. Although Zar1-null (Zar1(-/-)) mice are viable and grossly normal, Zar1(-/-) females are infertile. Ovarian development and oogenesis through the early stages of fertilization are evidently unimpaired, but most embryos from Zar1(-/-) females arrest at the one-cell stage. Distinct pronuclei form and DNA replication initiates, but the maternal and paternal genomes remain separate in arrested zygotes. Fewer than 20% of the embryos derived from Zar1(-/-) females progress to the two-cell stage and show marked reduction in the synthesis of the transcription-requiring complex, and no embryos develop to the four-cell stage. Thus, Zar1 is the first identified oocyte-specific maternal-effect gene that functions at the oocyte-to-embryo transition and, as such, offers new insights into the initiation of embryonic development and fertility control in mammals.


Asunto(s)
Proteínas del Huevo/fisiología , Embrión de Mamíferos/fisiología , Ratones/embriología , Oocitos/fisiología , Espermátides/fisiología , Cigoto/metabolismo , Secuencia de Aminoácidos , Animales , Northern Blotting , Southern Blotting , Western Blotting , Clonación Molecular , Replicación del ADN , Femenino , Fertilidad/fisiología , Fertilización In Vitro , Regulación de la Expresión Génica , Biblioteca de Genes , Cabras , Técnicas In Vitro , Masculino , Meiosis , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Embarazo , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido , Células Madre/fisiología
19.
ChemSusChem ; 16(12): e202300208, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37040093

RESUMEN

Novel antioxidants are synthesized by CuSO4 -catalyzed oxidative depolymerization of lignin to form aromatic aldehydes followed by aldol condensation with methyl ethyl ketone (MEK). Aldol condensation greatly improves the antioxidation ability of lignin depolymerized products. Three lignin monomeric aromatic aldehydes, - p-hydroxybenzaldehyde, vanillin, and syringaldehyde - are further employed for aldol condensation with MEK, resulting in successful synthesis of new antioxidants 1-(4-hydroxyphenyl)pent-1-en-3-one (HPPEO), 1-(4-hydroxy-3-methoxyphenyl)pent-1-en-3-one (HMPPEO), and 1-(4-hydroxy-3,5-dimethoxyphenyl)pent-1-en-3-one (HDMPPEO), respectively. Kinetic modeling illustrates that p-hydroxybenzaldehyde has the highest rate of reaction with MEK, followed by vanillin and then syringaldehyde, which is probably affected by the presence of methoxy groups. The syringaldehyde-derived product (HDMPPEO) displays the best antioxidation ability. As revealed by density functional theory calculations, electron-donating groups, such as methoxy, and conjugated side chains effectively improve the antioxidation ability. A hydrogen atom transfer (HAT) mechanism tends to occur in nonpolar solvents, whereas a sequential proton-loss electron transfer (SPLET) mechanism is favored in polar solvents. This work thus can inspire new pathways for valorization of lignin to produce high value-added products.


Asunto(s)
Antioxidantes , Lignina , Antioxidantes/química , Antioxidantes/metabolismo , Lignina/química , Aldehídos , Solventes/química , Estrés Oxidativo , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo
20.
Materials (Basel) ; 16(13)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37445011

RESUMEN

In this work, the solidification microstructure and phase transitions of Dy-Tb-Fe alloy samples were studied by using scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD) and differential thermal analysis (DTA). No stable ternary compound was detected in the present experiments. The phase transformation temperatures of eight Dy-Tb-Fe alloy samples were measured. Based on the experimental results determined in this work and reported in the literature, the phase equilibria of the Dy-Tb-Fe system was calculated using the CALPHAD method. The calculated vertical sections are consistent with the experimental results determined in this work and reported in the literature. Furthermore, in combination with the experimental solidification microstructure, the solidification behavior of Dy-Tb-Fe alloy samples was analyzed through the thermodynamic calculation with the Gulliver-Scheil non-equilibrium model. The simulated results agree well with the experimental results. This indicates that the reasonable thermodynamic parameters of the Dy-Tb-Fe system were finally obtained.

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