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1.
Hum Reprod ; 39(2): 364-373, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37995380

RESUMEN

STUDY QUESTION: What was the performance of different pretreatment prediction models for IVF, which were developed based on UK/US population (McLernon 2016 model, Luke model, Dhillon model, and McLernon 2022 model), in wider populations? SUMMARY ANSWER: For a patient in China, the published pretreatment prediction models based on the UK/US population provide similar discriminatory power with reasonable AUCs and underestimated predictions. WHAT IS KNOWN ALREADY: Several pretreatment prediction models for IVF allow patients and clinicians to estimate the cumulative probability of live birth in a cycle before the treatment, but they are mostly based on the population of Europe or the USA, and their performance and applicability in the countries and regions beyond these regions are largely unknown. STUDY DESIGN, SIZE, DURATION: A total of 26 382 Chinese patients underwent oocyte pick-up cycles between January 2013 and December 2020. PARTICIPANTS/MATERIALS, SETTING, METHODS: UK/US model performance was externally validated according to the coefficients and intercepts they provided. Centre-specific models were established with XGboost, Lasso, and generalized linear model algorithms. Discriminatory power and calibration of the models were compared as the forms of the AUC of the Receiver Operator Characteristic and calibration curves. MAIN RESULTS AND THE ROLE OF CHANCE: The AUCs for McLernon 2016 model, Luke model, Dhillon model, and McLernon 2022 model were 0.69 (95% CI 0.68-0.69), 0.67 (95% CI 0.67-0.68), 0.69 (95% CI 0.68-0.69), and 0.67 (95% CI 0.67-0.68), respectively. The centre-specific yielded an AUC of 0.71 (95% CI 0.71-0.72) with key predictors including age, duration of infertility, and endocrine parameters. All external models suggested underestimation. Among the external models, the rescaled McLernon 2022 model demonstrated the best calibration (Slope 1.12, intercept 0.06). LIMITATIONS, REASONS FOR CAUTION: The study is limited by its single-centre design and may not be representative elsewhere. Only per-complete cycle validation was carried out to provide a similar framework to compare different models in the sample population. Newer predictors, such as AMH, were not used. WIDER IMPLICATIONS OF THE FINDINGS: Existing pretreatment prediction models for IVF may be used to provide useful discriminatory power in populations different from those on which they were developed. However, models based on newer more relevant datasets may provide better calibrations. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Natural Science Foundation of China [grant number 22176159], the Xiamen Medical Advantage Subspecialty Construction Project [grant number 2018296], and the Special Fund for Clinical and Scientific Research of Chinese Medical Association [grant number 18010360765]. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Fertilización In Vitro , Infertilidad , Embarazo , Femenino , Humanos , Fertilización In Vitro/métodos , Infertilidad/terapia , Nacimiento Vivo , Modelos Lineales , Europa (Continente) , Tasa de Natalidad , Estudios Retrospectivos
2.
Chemistry ; 30(17): e202304165, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38246871

RESUMEN

A series of functional glycopolymer nanoparticles with 1,8-naphthalimide motif was designed, synthesized and applied for tumor cell imaging. With the pH-sensitive and aggregation-induced emission (AIE) effect of the 1,8-naphthalimide fluorescent probe, the presence of glucose-based glycopolymers enhanced its water-solubility and biocompatibility. Owing to the dual tumor-targeting effects of the dense glucose part and the boronic ester modification, the obtained glycopolymers showed high affinity to tumor cells, with a much faster staining rate than normal cells, indicating a great potential for diagnosis and treatments of cancers.


Asunto(s)
Colorantes Fluorescentes , Nanopartículas , Naftalimidas , Diagnóstico por Imagen , Glucosa
3.
Chemistry ; 30(9): e202303568, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38061996

RESUMEN

Selected gold complexes have been regarded as promising anti-cancer agents because they can bind with protein targets containing thiol or selenol moieties, but their clinical applications were hindered by the unbiased binding towards off-target thiol-proteins. Recently, a novel gold(III)-hydride complex (abbreviated as 1) with visible light-induced thiol reactivity has been reported as potent photo-activated anticancer agents (Angew. Chem. Int. Ed., 2020, 132, 11139). To explore new strategies to stimuli this potential antitumor drug, the effect of oriented external electric fields (OEEFs) on its geometric structure, electronic properties, and chemical reactivity was systematically investigated. Results reveal that imposing external electric fields along the Au-H bond of 1 can effectively activate this bond, which is conducive to its dissociation and the binding of Au site to potential targets. Hence, this study provides a new OEEF-strategy to activate this reported gold(III)-hydride, revealing its potential application in electrochemical therapy. We anticipate this work could promote the development of more electric field-activated anticancer agents. However, further experimental research should be conducted to verify the conclusions obtained in this work.


Asunto(s)
Antineoplásicos , Oro , Oro/química , Antineoplásicos/química , Electricidad , Compuestos de Sulfhidrilo
4.
Mol Biol Rep ; 51(1): 86, 2024 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-38183539

RESUMEN

BACKGROUND: PD-1 blockade has shown impressive clinical outcomes in colorectal cancers patients with high microsatellite instability (MSI-H). However, the majority of patients with colorectal cancer who present low microsatellite instability (MSI-L) or stable microsatellites (MSS) show little response to PD-1 blockade therapy. Here, we have demonstrated that Shikonin (SK) could induce cell death of CT26 cells via classically programmed and immunogenic pathways. METHODS AND RESULTS: SK promoted the membrane exposure of calreticulin and upregulated the expression of heat shock protein 70 (Hsp70). The upregulation of Hsp70 was dependent on ROS induced by SK and silencing of PKM2 in CT26 cells reverts ROS upregulation. Besides, SK synergizes with PD-1 blockade in CT26 tumor mice model, with the increase of intramural DC cells and CD8+ T cells. The expression of Hsp70 in tumor tissue was also increased in combinational SK plus αPD-1 therapy group. CONCLUSIONS: Our study elucidated the potential role of 'Shikonin-PKM2-ROS-Hsp70' axis in the promotion of efficacy of PD-1 blockade in CRC treatments, providing a potential strategy and targets for improving the efficacy of PD-1 blockade in colorectal cancer.


Asunto(s)
Neoplasias Colorrectales , Inestabilidad de Microsatélites , Humanos , Animales , Ratones , Receptor de Muerte Celular Programada 1 , Especies Reactivas de Oxígeno , Regulación hacia Arriba , Proteínas HSP70 de Choque Térmico/genética , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética
5.
Ophthalmic Res ; 67(1): 348-357, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38718781

RESUMEN

INTRODUCTION: Retinitis pigmentosa (RP) is a chronic progressive disease causing loss of visual acuity and ultimately blindness. This visual impairment can contribute to psychiatric comorbidity and worse overall quality of life (QOL). Our goal was to assess the relationship between the severity of disease for people with RP and QOL as it pertains to mental health, social support, disability resources, and financial factors. METHODS: This was a survey study conducted from June 2021 to February 2022 including 38 people with RP. QOL was assessed through a survey questionnaire focusing specifically on demographics, visual function, family, employment, social support, and mental health/well-being. Statistical analysis was conducted using a χ2 test for significance. RESULTS: A best corrected visual acuity (BCVA) of less than 20/200 (p = 0.0285) and living alone (p = 0.0358) were both statistically significant independent risk factors for experiencing depressive symptoms. Highest education level attained and unemployment rate were not found to be related to the development of depressive symptoms. Subjects had a higher unemployment rate (64% vs. US rate of 3.6%) and a high likelihood of reporting depressive symptoms (47.4%). CONCLUSION: People with RP are more likely to be unemployed and to develop depressive symptoms when compared to the general population. Similar to previous studies' findings, those with a BCVA of less than 20/200 were statistically more likely to experience depressive symptoms; living alone is a novel risk factor that is also associated with the presence of depressive symptoms. Contrary to prior findings, highest education level and unemployment status were found not to be related to the development of depressive symptoms. These patients may benefit from regular depression screenings and optional establishment of care with a psychiatrist or psychologist if they live alone or their BCVA is 20/200 or worse.


Asunto(s)
Calidad de Vida , Retinitis Pigmentosa , Agudeza Visual , Humanos , Retinitis Pigmentosa/psicología , Retinitis Pigmentosa/epidemiología , Retinitis Pigmentosa/complicaciones , Masculino , Femenino , Persona de Mediana Edad , Adulto , Encuestas y Cuestionarios , Anciano
6.
J Assist Reprod Genet ; 41(2): 347-358, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38040894

RESUMEN

PURPOSE: To evaluate the contribution of the cleavage stage morphological parameters to the prediction of blastocyst transfer outcomes. METHODS: A retrospective study was conducted on 8383 single-blastocyst transfer cycles including 2246 fresh and 6137 vitrified-warmed cycles. XGboost, LASSO, and GLM algorithms were employed to establish models for assessing the predictive value of the cleavage stage morphological parameters in transfer outcomes. Four models were developed using each algorithm: all-in model with or without day 3 morphology and embryo quality-only model with or without day 3 morphology. RESULTS: The live birth rate was 48.04% in the overall cohort. The AUCs of the models with the algorithm of XGboost were 0.83, 0.82, 0.63, and 0.60; with LASSO were 0.66, 0.66, 0.61, and 0.60; and with GLM were 0.66, 0.66, 0.61, and 0.60 respectively. In models 1 and 2, female age, basal FSH, peak E2, endometrial thickness, and female BMI were the top five critical features for predicting live birth; In models 3 and 4, the most crucial factor was blastocyst formation on D5 rather than D6. In model 3, incorporating cleavage stage morphology, including early cleavage, D3 cell number, and fragmentation, was significantly associated with successful live birth. Additionally, the live birth rates for blastocysts derived from on-time, slow, and fast D3 embryos were 49.7%, 39.5%, and 52%, respectively. CONCLUSIONS: The value of cleavage stage morphological parameters in predicting the live birth outcome of single blastocyst transfer is limited.


Asunto(s)
Transferencia de Embrión , Nacimiento Vivo , Embarazo , Femenino , Humanos , Estudios Retrospectivos , Desarrollo Embrionario , Tasa de Natalidad , Blastocisto , Índice de Embarazo
7.
Angew Chem Int Ed Engl ; : e202410514, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38966937

RESUMEN

Organic scintillators are praised for their abundant element reserves, facile preparation procedures, and rich structures. Herein, a new family of highly efficient organic phosphonium halide salts with thermally activated delayed fluorescence (TADF) are designed by innovatively adopting quaternary phosphonium as the electron acceptor, while dimethylamine group and halide anions (I-) serve as the electron donor. The prepared butyl(2-[2-(dimethylamino)phenyl]phenyl)diphenylphosphonium iodide (C4-I) exhibits bright blue emission and an ultra-high photoluminescence quantum yield (PLQY) of 100%. Efficient charge transfer is realized through the unique n-π and anion-π stacking in solid-state C4-I. Photophysical studies of C4-I suggest that the incorporation of I accounts for high intersystem crossing rate (kISC) and reverse intersystem crossing rate (kRISC), suppressing the intrinsic prompt fluorescence and enabling near-pure TADF emission at room temperature. Benefitting from the large Stokes shift, high PLQY, efficient exciton utilization, and remarkable X-ray attenuation ability endowed by I, C4-I delivers an outstanding light yield of 80721 photons/MeV and a low limit of detection (LoD) of 22.79 nGy·s-1. This work would provide a rational design concept and open up an appealing road for developing efficient organic scintillators with tunable emission, strong X-ray attenuation ability, and excellent scintillator performance.

8.
Anal Chem ; 95(42): 15595-15605, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37820038

RESUMEN

Electrochemical DNA (E-DNA) biosensors based on interface-mediated hybridization reactions are promising for point-of-care testing (POCT). However, the low efficiency of target recycle amplification and the steric hindrance at the electrode interface limit their sensing performance. Herein, we propose a base-stacking-driven catalytic hairpin assembly (BDCHA), a nucleic acid amplification reaction strategy, for POCT. The introduction of the base-stacking effect in this strategy increases the thermodynamic stability of the product, thereby effectively improving the recycling efficiency. Also, it enables the interface-mediated hybridization to maintain stability with even fewer bases in the reaction-binding domain, hence minimizing DNA secondary structure formation or intertwining at the electrode surface and ameliorating the steric hindrance limitation. The introduced base-stacking effect makes the electrode serve as a "booster" by integrating the advantages of homogeneous and heterogeneous reactions, giving BDCHA an increased reaction rate of about 20-fold, compared to the conventional catalytic hairpin assembly. As a proof of concept, our BDCHA was applied in constructing a portable E-DNA biosensor for the detection of a SARS-CoV-2 N gene sequence fragment. A simple 30 min one-pot incubation is required, and the results can be readily read on a smartphone, making it portable and user-friendly for POCT.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , ADN/química , Hibridación de Ácido Nucleico/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas Biosensibles/métodos , Electrodos , Pruebas en el Punto de Atención , Técnicas Electroquímicas/métodos , Límite de Detección
9.
Small ; 19(50): e2303403, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37649230

RESUMEN

Metal-organic frameworks (MOFs) have emerged as promising novel therapeutics for treating malignancies due to their tunable porosity, biocompatibility, and modularity to functionalize with various chemotherapeutics drugs. However, the design and synthesis of dual-stimuli responsive MOFs for controlled drug release in tumor microenvironments are vitally essential but still challenging. Meanwhile, the catalytic effect of metal ions selection and ratio optimization in MOFs for enhanced chemodynamic therapy (CDT) is relatively unexplored. Herein, a series of MnFe-based MOFs with pH/glutathione (GSH)-sensitivity are synthesized and then combined with gold nanoparticles (Au NPs) and cisplatin prodrugs (DSCP) as a cascade nanoreactor (SMnFeCGH) for chemo-chemodynamic-starvation synergistic therapy. H+ and GSH can specifically activate the optimal SMnFeCGH nanoparticles in cancer cells to release Mn2+/4+ /Fe2+/3+ , Au NPs, and DSCP rapidly. The optimal ratio of Mn/Fe shows excellent H2 O2 decomposition efficiency for accelerating CDT. Au NPs can cut off the energy supply to cancer cells for starvation therapy and strengthen CDT by providing large amounts of H2 O2 . Then H2 O2 is catalyzed by Mn2+ /Fe2+ to generate highly toxic •OH with the depletion of GSH. Meanwhile, the reduced DSCP accelerates cancer cell regression for chemotherapy. The ultrasensitivity cascade nanoreactor can enhance the anticancer therapeutic effect by combining chemotherapy, CDT, and starvation therapy.


Asunto(s)
Nanopartículas del Metal , Estructuras Metalorgánicas , Nanopartículas , Neoplasias , Humanos , Oro , Glutatión , Microambiente Tumoral , Nanotecnología , Concentración de Iones de Hidrógeno , Neoplasias/tratamiento farmacológico , Línea Celular Tumoral , Peróxido de Hidrógeno
10.
Biomacromolecules ; 24(1): 109-117, 2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36461924

RESUMEN

Three-dimensional (3D) printable hydrogels with a shape memory effect have emerged as a new class of 4D printing materials recently and found wide applications in various fields. However, synergistically endowing such materials with good mechanical strength and biocompatibility for biomedical uses remains challenging. In this study, a series of multiresponsive hydrogels have been prepared through a dynamic covalent imine/Diels-Alder network from biocompatible starting materials of modified gelatin and poly(ethylene glycol)-based polymers. By further secondary crosslinking with a hyperbranched triethoxysilane reagent (HPASi) that contains multiple supramolecular hydrogen bonding, the hydrogels presented a strengthened self-healing and temperature-responsive shape memory effect. With the additional features of superior stretchability (elongation at break up to 523%), good cytocompatibility, and 3D printable properties, these multifunctional hydrogels showed great potential for broad biomedical applications.


Asunto(s)
Gelatina , Hidrogeles , Materiales Biocompatibles/farmacología , Hidrogeles/farmacología , Polímeros , Impresión
11.
Biomacromolecules ; 24(12): 5898-5904, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-37957110

RESUMEN

CpG ODNs demonstrate a significant promise for immunotherapy. However, their application is limited owing to quick DNase digestion and inadequate cellular internalization. Transportation of CpG ODNs into immune cells is crucial. Although viral vectors exhibit high transfection efficiency, safety risks, high cost, and low carrying capacity remain big obstacles. Herein, a novel CpG ODNs vector was fabricated by using starch. Starch was ultrasonicated and simply aminated (NH2-St) through grafting with diethylenetriamine, which was spherical with a diameter of 50 nm. NH2-St possessed good biocompatibility. Cationic NH2-St encapsulated CpG ODNs well and possessed a high loading capacity of 317 µg/mg. NH2-St protected CpG ODNs from nuclease digestion and significantly enhanced their cellular uptake. NH2-St/CpG induced the potent secretion of antitumor cytokines from macrophages and effectively suppressed the growth of tumor cells. This work highlights the promise of starch for CpG ODNs delivery, which brings new hope for cancer immunotherapy.


Asunto(s)
Adyuvantes Inmunológicos , Nanopartículas , Adyuvantes Inmunológicos/farmacología , Citocinas , Macrófagos , Oligodesoxirribonucleótidos/farmacología
12.
Biomarkers ; 28(5): 427-436, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37036017

RESUMEN

Background: Circulating tumour DNA (ctDNA) has demonstrated robust diagnostic accuracy in several digestive cancers. However, the prognostic role of ctCDNA in gastric cancer (GC) is still controversial. This systematic review and meta-analysis aimed to evaluate the prognostic value of ctDNA in GC.Methods: PubMed, Web of Science and Cochrane databases were searched to identify studies reporting the use of ctDNA to predict GC outcome and all relevant studies published until November 2022 were enrolled for our analysis. Data were extracted by two authors independently and statistic analysis was conducted by R program with 'meta' and 'metafor' packages.Results: A total of 34 qualified articles with 5091 subjects were incorporated into our meta-analysis. The corresponding Hazard ratio (HR) of overall survival (OS), disease-free survival (DFS) and progression-free survival (PFS) were 2.74 (95% CI:2.24-3.35), 3.13 (95% CI:2.08-4.72) and 3.04 (95% CI:2.46-3.76), respectively, in GC patients.Conclusion: Blood-based ctDNA assay would be a potential novel biomarker for GC evaluation and prediction.Simple Summary: This is the integrated meta-analysis on the association of circulating tumour DNA (ctDNA) and prognosis of gastric cancer (GC) with an increasing number of studies exploring the prognostic value of GC in the last few years, which depicted that the detection of ctDNA could be a promising predictor in GC patients.


Asunto(s)
ADN Tumoral Circulante , Neoplasias Gástricas , Humanos , Pronóstico , ADN Tumoral Circulante/genética , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/análisis , Supervivencia sin Enfermedad
13.
Mol Biol Rep ; 50(4): 3167-3177, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36696022

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is one of the cancers with high morbidity and mortality worldwide. Chemotherapy is commonly used for metastatic or more advanced CRC. The mechanism of CRC chemoresistance is still under active investigation. Therefore, we identify and validate differentially expressed genes (DEGs) between oxaliplatin/5-FU resistant and sensitive CRC cells. METHODS AND RESULTS: Three datasets of colorectal cancer patients (GSE28691, GSE81006, and GSE77932) from the Gene Expression Omnibus (GEO) database were analyzed and volcano plots for DEGs were generated using the GEO2R tool. The intersection of three GEO datasets showed that GABRP was significantly upregulated in chemo-resistant CRC cells or patients with an adjusted p-value less than 0.01. The potential protein-protein interaction (PPI) network with GABRP was analyzed by the Search Tool for the Retrieval of Interaction Gene/Proteins (STRING) website. The PPI network predicted ANKRD66, CLINT1, HAP1, PLCL1, GABARPAP, GABARAPL1, NSF, GABARAPL2, TRAK2, and CLIC3 had a high likelihood to interact with GABRP. Especially, GABARAP, GABARAPL1, ANKRD66, CLINT1, and CLIC3 were enriched as the most possibly associated proteins with GABRP among the networks. GABRP was significantly more expressed in both oxaliplatin/5-FU resistant CRC cells than in those counterpart sensitive CRC cells using quantitative PCR (qPCR) analysis. Consistently, TCGA, Oncomine, and Human Protein Atlas (HPA) databases confirmed that higher expression of GABRP was robustly found in CRC patients than those in other various cancer types or normal colon tissues. CONCLUSION: We identify GABRP as a promising drug target to mediate oxaliplatin or 5-FU resistance in CRC. It provided the theoretical basis and potential clinical value for CRC patients.


Asunto(s)
Neoplasias Colorrectales , Resistencia a Antineoplásicos , Humanos , Oxaliplatino/farmacología , Resistencia a Antineoplásicos/genética , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Proteínas/genética , Fluorouracilo/farmacología , Fluorouracilo/uso terapéutico , Regulación Neoplásica de la Expresión Génica
14.
Anal Bioanal Chem ; 415(29-30): 7139-7150, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37803135

RESUMEN

In this work, an upconversion luminescence (UCL) nanosensor for fast detection of ferric ion (Fe3+) and phosphate ion (Pi) is developed based on the inner-filter effect (IFE) between NaYF4:Yb/Er upconversion nanoparticles (UCNPs) and Fe3+-hypocrellin B (HB) complex. Fe3+-HB complex has strong absorption band (450-650 nm), which overlaps with the green emission peak of UCNPs at 545 nm. By adding Fe3+ and Pi, the UCNPs-HB system produces the red-shift change of absorption spectrum, which leads to the "on-off-on" process of IFE. So, with the specific recognition ability of HB for Fe3+ and the competitive complexation of Pi for Fe3+, the proposed nanosensor utilizes the UCL change to achieve the detection of the targets. For the detections of Fe3+, the linear range is 10-600 µM with a limit of detection (LOD) of 2.62 µM, and for Pi, the linear range is 5-100 µM with a LOD of 1.25 µM. The results for selectivity, precision, and recovery test are also satisfactory. Furthermore, the real sample detection shows that the proposed nanaosensor has a great potential in environmental and biological systems. An upconversion luminescence (UCL) nanosensor based on the inner-filter effect (IFE) between upconversion nanoparticles (UCNPs) and Fe3+-hypocrellin B (HB) complex for the detection of Fe3+ and phosphate ion has been proposed, which is promising to be a convenient and sensitive assay for monitoring Fe3+ and phosphate ion in different environments and biological systems.

15.
Phys Chem Chem Phys ; 25(47): 32525-32533, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37997746

RESUMEN

Catalytic conversion of N2O and CO into nonharmful gases is of great significance to reduce their adverse impact on the environment. The potential of the WSi12 superatom to serve as a new cluster catalyst for CO oxidation by N2O is examined for the first time. It is found that WSi12 prefers to adsorb the N2O molecule rather than the CO molecule, and the charge transfer from WSi12 to N2O results in the full activation of N2O into a physically absorbed N2 molecule and an activated oxygen atom that is attached to an edge of the hexagonal prism structure of WSi12. After the release of N2, the remaining oxygen atom can oxidize one CO molecule via overcoming a rate-limiting barrier of 28.19 kcal mol-1. By replacing the central W atom with Cr and Mo, the resulting MSi12 (M = Cr and Mo) superatoms exhibit catalytic performance for CO oxidation comparable to the parent WSi12. In particular, the catalytic ability of WSi12 for CO oxidation is well maintained when it is extended into tube-like WnSi6(n+1) (n = 2, 4, and 6) clusters with energy barriers of 25.63-29.50 kcal mol-1. Moreover, all these studied MSi12 (M = Cr, Mo, and W) and WnSi6(n+1) (n = 2, 4, and 6) species have high structural stability and can absorb sunlight to drive the catalytic process. This study not only opens a new door for the atomically precise design of new silicon-based nanoscale catalysts for various chemical reactions but also provides useful atomic-scale insights into the size effect of such catalysts in heterogeneous catalysis.

16.
Nature ; 543(7643): 131-135, 2017 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-28219079

RESUMEN

Photosystem II (PSII) is a huge membrane-protein complex consisting of 20 different subunits with a total molecular mass of 350 kDa for a monomer. It catalyses light-driven water oxidation at its catalytic centre, the oxygen-evolving complex (OEC). The structure of PSII has been analysed at 1.9 Å resolution by synchrotron radiation X-rays, which revealed that the OEC is a Mn4CaO5 cluster organized in an asymmetric, 'distorted-chair' form. This structure was further analysed with femtosecond X-ray free electron lasers (XFEL), providing the 'radiation damage-free' structure. The mechanism of O=O bond formation, however, remains obscure owing to the lack of intermediate-state structures. Here we describe the structural changes in PSII induced by two-flash illumination at room temperature at a resolution of 2.35 Å using time-resolved serial femtosecond crystallography with an XFEL provided by the SPring-8 ångström compact free-electron laser. An isomorphous difference Fourier map between the two-flash and dark-adapted states revealed two areas of apparent changes: around the QB/non-haem iron and the Mn4CaO5 cluster. The changes around the QB/non-haem iron region reflected the electron and proton transfers induced by the two-flash illumination. In the region around the OEC, a water molecule located 3.5 Å from the Mn4CaO5 cluster disappeared from the map upon two-flash illumination. This reduced the distance between another water molecule and the oxygen atom O4, suggesting that proton transfer also occurred. Importantly, the two-flash-minus-dark isomorphous difference Fourier map showed an apparent positive peak around O5, a unique µ4-oxo-bridge located in the quasi-centre of Mn1 and Mn4 (refs 4,5). This suggests the insertion of a new oxygen atom (O6) close to O5, providing an O=O distance of 1.5 Å between these two oxygen atoms. This provides a mechanism for the O=O bond formation consistent with that proposed previously.


Asunto(s)
Cristalografía/métodos , Electrones , Rayos Láser , Luz , Oxígeno/química , Oxígeno/efectos de la radiación , Complejo de Proteína del Fotosistema II/química , Complejo de Proteína del Fotosistema II/efectos de la radiación , Biocatálisis/efectos de la radiación , Cianobacterias/química , Transporte de Electrón/efectos de la radiación , Análisis de Fourier , Manganeso/química , Manganeso/metabolismo , Modelos Moleculares , Proteínas de Hierro no Heme/química , Proteínas de Hierro no Heme/metabolismo , Proteínas de Hierro no Heme/efectos de la radiación , Oxígeno/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Protones , Temperatura , Factores de Tiempo , Agua/química , Agua/metabolismo
17.
BMC Surg ; 23(1): 131, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37194000

RESUMEN

BACKGROUND: To explore the clinical prognostic utility of the preoperative cholesterol-to-lymphocyte ratio (CLR) in outcomes for colorectal cancer liver metastasis (CRLM) patients receiving simultaneous resection of the primary lesion and liver metastases. METHODS: A total of 444 CRLM patients receiving simultaneous resections were enrolled. The optimal cut-off value for CLR was determined using the highest Youden's index. Patients were divided into the CLR < 3.06 group and the CLR≥3.06 group. Propensity score matching analysis (PSM) and the inverse probability of treatment weighting (IPTW) method were conducted to eliminate bias between the two groups. The outcomes included short-term outcomes and long-term outcomes. Kaplan-Meier curves and log-rank tests were used to analyse progression-free survival (PFS) and overall survival (OS). RESULTS: In the short-term outcome analysis, after 1:1 PSM, 137 patients were distributed to the CLR < 3.06 group and CLR≥3.06 group. No significant difference was noted between the two groups (P > 0.1). Compared with patients with CLR < 3.06, patients with CLR≥3.06 had comparable operation times (320.0 [272.5-421.0] vs. 360.0 [292.5-434.5], P = 0.088), blood loss (200.0 [100.0-400.0] vs. 200.0 [150.0-450.0], P = 0.831), postoperative complication rates (50.4% vs. 46.7%, P = 0.546) and postoperative ICU rates (5.8% vs. 11.7%, P = 0.087). In the long-term outcome analysis, Kaplan-Meier analysis showed that compared with patients with CLR < 3.06, patients with CLR≥3.06 had worse PFS (P = 0.005, median: 10.2 months vs. 13.0 months) and OS (P = 0.002, median: 41.0 months vs. 70.9 months). IPTW-adjusted Kaplan-Meier analysis showed that the CLR≥3.06 group had worse PFS (P = 0.027) and OS (P = 0.010) than the CLR < 3.06 group. In the IPTW-adjusted Cox proportional hazards regression analysis, CLR≥3.06 was an independent factor for PFS (HR = 1.376, 95% CI 1.097-1.726, P = 0.006) and OS (HR = 1.723, 95% CI 1.218-2.439, P = 0.002). IPTW-adjusted Cox proportional hazards regression analysis including postoperative complications, operation time, intraoperative blood loss, intraoperative blood transfusion and postoperative chemotherapy revealed that CLR≥3.06 was an independent factor for PFS (HR = 1.617, 95% CI 1.252-2.090, P < 0.001) and OS (HR = 1.823, 95% CI 1.258-2.643, P = 0.002). CONCLUSIONS: The preoperative CLR level predicts unfavourable outcomes in CRLM patients receiving simultaneous resection of the primary lesion and liver metastases and should be taken into consideration when developing treatment and monitoring strategies.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , Humanos , Estudios Retrospectivos , Neoplasias Colorrectales/patología , Hepatectomía/métodos , Pronóstico , Linfocitos/patología , Complicaciones Posoperatorias/etiología , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/secundario
18.
Mikrochim Acta ; 191(1): 15, 2023 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-38087000

RESUMEN

Based on upconversion nanoparticles (UCNPs) as energy donor and herring sperm DNA (hsDNA) as molecular recognition element, an unlabelled upconversion luminescence (UCL) affinity biosensor was constructed for the detection of anthraquinone (AQ) anticancer drugs in biological fluids. AQ anticancer drugs can insert into the double helix structure of hsDNA on the surface of UCNPs, thereby shortening the distance from UCNPs. Therefore, the luminescence resonance energy transfer (LRET) phenomenon is effectively triggered between UCNPs and AQ anticancer drugs. Hence, AQ anticancer drugs can be quantitatively detected according to the UCL quenching rate. The biosensor showed good sensitivity and stability for the detection of daunorubicin (DNR) and doxorubicin (ADM). For the detection of DNR, the linear range is 1-100 µg·mL-1 with a limit of detection (LOD) of 0.60 µg·mL-1, and for ADM, the linear range is 0.5-100 µg·mL-1 with a LOD of 0.38 µg·mL-1. The proposed biosensor provides a convenient method for monitoring AQ anticancer drugs in clinical biological fluids in the future.


Asunto(s)
Antineoplásicos , Técnicas Biosensibles , Masculino , Humanos , Semen , ADN , Técnicas Biosensibles/métodos , Antraquinonas
19.
J Integr Plant Biol ; 65(1): 223-234, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36125941

RESUMEN

The photosynthetic reaction center complex (RCC) of green sulfur bacteria (GSB) consists of the membrane-imbedded RC core and the peripheric energy transmitting proteins called Fenna-Matthews-Olson (FMO). Functionally, FMO transfers the absorbed energy from a huge peripheral light-harvesting antenna named chlorosome to the RC core where charge separation occurs. In vivo, one RC was found to bind two FMOs, however, the intact structure of RCC as well as the energy transfer mechanism within RCC remain to be clarified. Here we report a structure of intact RCC which contains a RC core and two FMO trimers from a thermophilic green sulfur bacterium Chlorobaculum tepidum at 2.9 Å resolution by cryo-electron microscopy. The second FMO trimer is attached at the cytoplasmic side asymmetrically relative to the first FMO trimer reported previously. We also observed two new subunits (PscE and PscF) and the N-terminal transmembrane domain of a cytochrome-containing subunit (PscC) in the structure. These two novel subunits possibly function to facilitate the binding of FMOs to RC core and to stabilize the whole complex. A new bacteriochlorophyll (numbered as 816) was identified at the interspace between PscF and PscA-1, causing an asymmetrical energy transfer from the two FMO trimers to RC core. Based on the structure, we propose an energy transfer network within this photosynthetic apparatus.


Asunto(s)
Carcinoma de Células Renales , Chlorobi , Neoplasias Renales , Proteínas del Complejo del Centro de Reacción Fotosintética , Proteínas del Complejo del Centro de Reacción Fotosintética/química , Proteínas del Complejo del Centro de Reacción Fotosintética/metabolismo , Chlorobi/química , Chlorobi/metabolismo , Microscopía por Crioelectrón , Proteínas Bacterianas/metabolismo
20.
J Pak Med Assoc ; 73(2): 249-252, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36800704

RESUMEN

OBJECTIVE: To investigate the distribution of helicobacter pylori-related genotypes of oipA, babA2, and babB in patients with gastrointestinal diseases. Methods: The retrospective study was conducted at the Jiamusi College, Heilongjiang University of Traditional Chinese Medicine, Harbin, China, and comprised data from February 2017 to May 2020 of patients of either gender 20-80 years who underwent gastroscopy. An instrument based on polymerase chain reaction was used to amplify oipA, babA2 and babB genes, and their distribution in terms of gender, age and pathological types was analysed. RESULTS: Among the 116 patients, 52(44.8%) had oipA genotype, 48(41.2%) babA2, and 72 (62.1%) babB, respectively, and the size of amplified products of 486bp, 219bp and 362bp, respectively. The infection rate of oipA and babB genotypes was highest [26(50.0%) and 31(43.1%)]in those aged 61-80 years, and lowest [9(17.3%) and 15(20.8%)]in those aged 20-40 years. The infection rate of babA2 genotype was highest [23(47.9%)] in those aged 41-60 years, and lowest [12(25.0%)] in those aged 61-80 years. Male patients were under a higher [28(53.9%) and 26(54.2%)] rate of infection with oipA and babA2, and female patients has a higher [40(55.6%)] rate of infection with babB. Among Hp-infected patients with digestive diseases, babB genotype was mainly found in patients with chronic superficial gastritis[17(58.6%)], duodenal ulcer[17(85.0%)], chronic atrophic gastritis[19(59.4%)] and gastric ulcer[16(72.7%)], while oipA genotype was mainly found in patients with gastric cancer[8(61.5%)]. CONCLUSIONS: Chronic superficial gastritis, duodenal ulcer, chronic atrophic gastritis, and gastric ulcer may have a close bearing on babB genotype infection, while oipA genotype infection may be associated with gastric cancer.


Asunto(s)
Úlcera Duodenal , Gastritis Atrófica , Helicobacter pylori , Enfermedades Musculoesqueléticas , Neoplasias Gástricas , Úlcera Gástrica , Humanos , Femenino , Masculino , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/genética , Helicobacter pylori/genética , Estudios Retrospectivos , Genotipo
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