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1.
Immunity ; 47(1): 159-170.e10, 2017 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-28723548

RESUMO

Clearance of pathogens or tumor cells by antibodies traditionally requires both Fab and Fc domains of IgG. Here, we show the Fc domain of IgG alone mediates recognition and clearance of herpes simplex virus (HSV1)-infected cells. The human natural killer (NK) cell surface is naturally coated with IgG bound by its Fc domain to the Fcγ receptor CD16a. NK cells utilize the Fc domain of bound IgG to recognize gE, an HSV1-encoded glycoprotein that also binds the Fc domain of IgG but at a site distinct from CD16a. The bridge formed by the Fc domain between the HSV1-infected cell and the NK cell results in NK cell activation and lysis of the HSV1-infected cell in the absence of HSV1-specific antibody in vitro and prevents fatal HSV1 infection in vivo. This mechanism also explains how bacterial IgG-binding proteins regulate NK cell function and may be broadly applicable to Fcγ-receptor-bearing cells.


Assuntos
Anticorpos Antivirais/metabolismo , Herpes Simples/imunologia , Fragmentos Fc das Imunoglobulinas/metabolismo , Imunoglobulina G/metabolismo , Células Matadoras Naturais/imunologia , Simplexvirus/imunologia , Animais , Anticorpos Antivirais/imunologia , Células Cultivadas , Citotoxicidade Imunológica , Feminino , Humanos , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ligação Proteica , Agregação de Receptores , Receptores de IgG/metabolismo , Transdução de Sinais , Proteínas Virais/imunologia
2.
Plant J ; 118(1): 24-41, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38102874

RESUMO

Abscisic acid (ABA) is involved in salt and drought stress responses, but the underlying molecular mechanism remains unclear. Here, we demonstrated that the overexpression of MdMYB44-like, an R2R3-MYB transcription factor, significantly increases the salt and drought tolerance of transgenic apples and Arabidopsis. MdMYB44-like inhibits the transcription of MdPP2CA, which encodes a type 2C protein phosphatase that acts as a negative regulator in the ABA response, thereby enhancing ABA signaling-mediated salt and drought tolerance. Furthermore, we found that MdMYB44-like and MdPYL8, an ABA receptor, form a protein complex that further enhances the transcriptional inhibition of the MdPP2CA promoter by MdMYB44-like. Significantly, we discovered that MdPP2CA can interfere with the physical association between MdMYB44-like and MdPYL8 in the presence of ABA, partially blocking the inhibitory effect of the MdMYB44-like-MdPYL8 complex on the MdPP2CA promoter. Thus, MdMYB44-like, MdPYL8, and MdPP2CA form a regulatory loop that tightly modulates ABA signaling homeostasis under salt and drought stress. Our data reveal that MdMYB44-like precisely modulates ABA-mediated salt and drought tolerance in apples through the MdPYL8-MdPP2CA module.


Assuntos
Arabidopsis , Malus , Malus/genética , Malus/metabolismo , Resistência à Seca , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Cloreto de Sódio/farmacologia , Arabidopsis/metabolismo , Ácido Abscísico/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico
3.
Nucleic Acids Res ; 51(17): 8909-8924, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37604686

RESUMO

Archaeal ribosomes have many domain-specific features; however, our understanding of these structures is limited. We present 10 cryo-electron microscopy (cryo-EM) structures of the archaeal ribosome from crenarchaeota Sulfolobus acidocaldarius (Sac) at 2.7-5.7 Å resolution. We observed unstable conformations of H68 and h44 of ribosomal RNA (rRNA) in the subunit structures, which may interfere with subunit association. These subunit structures provided models for 12 rRNA expansion segments and 3 novel r-proteins. Furthermore, the 50S-aRF1 complex structure showed the unique domain orientation of aRF1, possibly explaining P-site transfer RNA (tRNA) release after translation termination. Sac 70S complexes were captured in seven distinct steps of the tRNA translocation reaction, confirming conserved structural features during archaeal ribosome translocation. In aEF2-engaged 70S ribosome complexes, 3D classification of cryo-EM data based on 30S head domain identified two new translocation intermediates with 30S head domain tilted 5-6° enabling its disengagement from the translocated tRNA and its release post-translocation. Additionally, we observed conformational changes to aEF2 during ribosome binding and switching from three different states. Our structural and biochemical data provide new insights into archaeal translation and ribosome translocation.


Archaeal ribosomes display variations in their ribosomal proteins and ribosomal RNA (rRNA) expansion segments (ESs). Protein translation in archaea combines features in both bacterial and eukaryotic translation. In this study, we present 10 cryo-electron microscopy structures of the archaeal ribosome from crenarchaeota Sulfolobus acidocaldarius (Sac). The 50S and 30S subunit structures present 3 novel ribosomal proteins and 12 rRNA ESs. The 70S Sac ribosome structures were captured in seven distinct functional states, including pre-, intermediate- and post-translocation states. Specifically, we identified two novel translocation intermediates, in which the 30S subunit head domain tilts outward to release the translocated P-site transfer RNA. The structures of archaeal ribosomes provide insights into the archaeal translation and ribosome translocation.


Assuntos
Ribossomos , Sulfolobus acidocaldarius , Microscopia Crioeletrônica , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , RNA Ribossômico/metabolismo , RNA de Transferência/metabolismo , Sulfolobus acidocaldarius/citologia , Sulfolobus acidocaldarius/metabolismo
4.
Langmuir ; 40(18): 9543-9555, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38651309

RESUMO

Corrosion protection of metal has become an important and urgent topic, which requires the development of an inexpensive, environmentally friendly, and highly efficient corrosion inhibitor. Herein, a sweet potato leaf extract (SPL) was obtained by a simple water-based extraction method and then as a green corrosion inhibitor for 6N01 Al alloy in the seawater was well investigated by the weight loss method and various electrochemical tests. Fourier transform infrared (FT-IR) and ultraviolet-visible (UV-vis) spectroscopies were carried out to investigate the compositions of SPL. The findings from the potentiodynamic polarization (PDP) curves suggest that SPL functions as a typical mixed-type corrosion inhibitor. Notably, the maximum corrosion inhibition efficiency reaches 94.6% following a 36 h immersion period at 25 °C. The adsorption behavior of SPL on the Al alloy surface belongs to the Langmuir adsorption isotherm. The Gibbs free energy value illustrates that the adsorption of SPL contains both physisorption and chemisorption. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) indicate that SPL is firmly attached to the Al alloy surface by making a protective layer, which can effectively inhibit the corrosion of the Al alloy in the seawater. Furthermore, quantum chemical calculations were applied to validate the chemical adsorption and elucidate the relationship between the electronic structure of the active components in SPL and their effectiveness in corrosion inhibition.

5.
J Org Chem ; 89(5): 3605-3611, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38364322

RESUMO

D-A type axially chiral biphenyl luminescent molecules are directly constructed through ingenious functionalization of the octahydro-binaphthol skeleton without optical resolution. The circularly polarized organic light-emitting diodes based on them display remarkable circularly polarized electroluminescence emission, a high luminance of >10 000 cd m-2, a maximum external quantum efficiency of 6.6%, and an extremely low-efficiency roll-off. This work provides a universal strategy for developing efficient and diverse axially chiral biphenyl emitters.

6.
Inorg Chem ; 63(16): 7113-7117, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38578870

RESUMO

The strategy of flow channel with wrinkles and calcium sites for single-step C2H4 purification from C2 gases and methanol-to-olefins (MTO) products separation was realized in FJI-Y9. The adsorption amounts showed a total reversal order of C3H6 > C2H6 > C2H2 > C2H4 at 298 K. Modeling indicated that the wrinkles and Ca2+ facilitated the full contact of C3H6 and C2H6. Breakthrough experiments illustrated that FJI-Y9 could yield pure C2H4 in a single step with a productivity of 0.78 mmol g-1. In a lone adsorption/desorption cycle for MTO product separation, the productivities of C3H6 and C2H4 were 1.96 and 1.29 mol g-1, standing as the highest recorded values.

7.
J Med Internet Res ; 26: e48443, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38271060

RESUMO

BACKGROUND: The widespread use of electronic health records in the clinical and biomedical fields makes the removal of protected health information (PHI) essential to maintain privacy. However, a significant portion of information is recorded in unstructured textual forms, posing a challenge for deidentification. In multilingual countries, medical records could be written in a mixture of more than one language, referred to as code mixing. Most current clinical natural language processing techniques are designed for monolingual text, and there is a need to address the deidentification of code-mixed text. OBJECTIVE: The aim of this study was to investigate the effectiveness and underlying mechanism of fine-tuned pretrained language models (PLMs) in identifying PHI in the code-mixed context. Additionally, we aimed to evaluate the potential of prompting large language models (LLMs) for recognizing PHI in a zero-shot manner. METHODS: We compiled the first clinical code-mixed deidentification data set consisting of text written in Chinese and English. We explored the effectiveness of fine-tuned PLMs for recognizing PHI in code-mixed content, with a focus on whether PLMs exploit naming regularity and mention coverage to achieve superior performance, by probing the developed models' outputs to examine their decision-making process. Furthermore, we investigated the potential of prompt-based in-context learning of LLMs for recognizing PHI in code-mixed text. RESULTS: The developed methods were evaluated on a code-mixed deidentification corpus of 1700 discharge summaries. We observed that different PHI types had preferences in their occurrences within the different types of language-mixed sentences, and PLMs could effectively recognize PHI by exploiting the learned name regularity. However, the models may exhibit suboptimal results when regularity is weak or mentions contain unknown words that the representations cannot generate well. We also found that the availability of code-mixed training instances is essential for the model's performance. Furthermore, the LLM-based deidentification method was a feasible and appealing approach that can be controlled and enhanced through natural language prompts. CONCLUSIONS: The study contributes to understanding the underlying mechanism of PLMs in addressing the deidentification process in the code-mixed context and highlights the significance of incorporating code-mixed training instances into the model training phase. To support the advancement of research, we created a manipulated subset of the resynthesized data set available for research purposes. Based on the compiled data set, we found that the LLM-based deidentification method is a feasible approach, but carefully crafted prompts are essential to avoid unwanted output. However, the use of such methods in the hospital setting requires careful consideration of data security and privacy concerns. Further research could explore the augmentation of PLMs and LLMs with external knowledge to improve their strength in recognizing rare PHI.


Assuntos
Inteligência Artificial , Registros Eletrônicos de Saúde , Humanos , Processamento de Linguagem Natural , Privacidade , China
8.
Molecules ; 29(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38930832

RESUMO

In this research, with an aim to develop novel pyrazole oxime ether derivatives possessing potential biological activity, thirty-two pyrazole oxime ethers, including a substituted pyridine ring, have been synthesized and structurally identified through 1H NMR, 13C NMR, and HRMS. Bioassay data indicated that most of these compounds owned strong insecticidal properties against Mythimna separata, Tetranychus cinnabarinus, Plutella xylostella, and Aphis medicaginis at a dosage of 500 µg/mL, and some title compounds were active towards Nilaparvata lugens at 500 µg/mL. Furthermore, some of the designed compounds had potent insecticidal effects against M. separata, T. cinnabarinus, or A. medicaginis at 100 µg/mL, with the mortalities of compounds 8a, 8c, 8d, 8e, 8f, 8g, 8o, 8s, 8v, 8x, and 8z against A. medicaginis, in particular, all reaching 100%. Even when the dosage was lowered to 20 µg/mL, compound 8s also expressed 50% insecticidal activity against M. separata, and compounds 8a, 8e, 8f, 8o, 8v, and 8x displayed more than 60% inhibition rates against A. medicaginis. The current results provided a significant basis for the rational design of biologically active pyrazole oxime ethers in future.


Assuntos
Desenho de Fármacos , Inseticidas , Oximas , Pirazóis , Pirazóis/química , Pirazóis/farmacologia , Pirazóis/síntese química , Oximas/química , Oximas/farmacologia , Oximas/síntese química , Inseticidas/química , Inseticidas/síntese química , Inseticidas/farmacologia , Animais , Relação Estrutura-Atividade , Éteres/química , Estrutura Molecular , Piridinas/química , Piridinas/farmacologia , Piridinas/síntese química , Mariposas/efeitos dos fármacos
9.
Anal Chem ; 95(26): 9967-9974, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37341470

RESUMO

A stable and reusable electrochemiluminescent (ECL) signal amplification strategy was proposed through a pyrene-based conjugated polymer (Py-CP) triggered self-circulating enhancement system. Specifically, the delocalized conjugated π-electrons of Py-CPs made it an excellent coreactant to arouse the initial ECL signal improvement of Ru(phen)32+, but the subsequent signal reduction was attributed to the consumption of Py-CPs, in which this stage was called the signal sensitization evoking phase (SSEP). Then, the maximum use of ECL luminescence of Ru(phen)32+ produced in the SSEP was made to irradiate the photosensitizer Py-CPs for in situ producing numerous ·OH, and a stronger and more stable ECL response stage defined as the signal sensitization stabilize phase was reached. Encouragingly, the incorporation of Nb2C MXene quantum dots with an exceptional physicochemical property not only foreshortens the SSEP for quickly acquiring a stable ECL signal but also introduces the photoacoustic (PA) transduce mechanism for achieving dual-signal outputting. Ultimately, the portable and miniaturized ECL-PA synergetic sensing platform based on the closed-bipolar electrode realized sensitive let-7a detection in a wide linear range from 10-9 to 10-2 nM with a low detection limit of 3.3 × 10-10 nM and also demonstrated good selectivity, excellent stability, and high reliability. The successful application of an innovative signal transduction mechanism and dexterous coupling modality will provide new insights for advancing the development of flexible analytical devices.


Assuntos
Técnicas Biossensoriais , Neoplasias Pulmonares , Humanos , Polímeros/química , Reprodutibilidade dos Testes , Medições Luminescentes , Técnicas Eletroquímicas , Pirenos , Neoplasias Pulmonares/diagnóstico
10.
Anal Chem ; 95(36): 13629-13637, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37624588

RESUMO

Given that exosomes released from cancer cells carry various tumor-specific proteins on their surface, they have emerged as a source of biomarkers for cancer diagnosis. However, developing accurate and reliable assays to detect exosomes in the early stages of disease with low abundance and complex systems remains challenging. Here, the prepared PDIG film has the ability to sense multiple signals from a single stimulus, in which the presence of cobalt(II) chloride and deep eutectic solvents (DES) endows PDIG with thermochromic and thermosensitive properties. Concretely, the PDIG served as the recognition interface in series with a bipolar electrode (BPE) that exhibits a highly sensitive color and conductivity response to temperature stimuli triggered by the light-harvesting probe TiO2@CNOs introduced via proximity hybridization assay triggering a rolling circle amplification strategy, resulting in the output of colorimetric, photoacoustic, and electrochemiluminescent signals for the detection of colorectal cancer exosomes. This work is expected to provide a new direction for exploring the multisignal amplification strategy of BPE, broaden the application of BPE in biological analysis, and provide new insights for developing highly information-sensing elements to ensure the multimodal coupling for cancer-specific exosome detection.


Assuntos
Exossomos , Bioensaio , Cloretos , Cobalto , Colorimetria , Proteínas de Neoplasias
11.
Cancer Immunol Immunother ; 72(8): 2769-2782, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37166484

RESUMO

Anti-PD-1 monotherapy had limited clinical efficacy in relapsed/refractory (r/r) AML patients with higher PD-1 and PD-L1 expression. Hence, we investigated the efficacy and safety of PD-1 inhibitor with DNA hypomethylating agent (HMA) + CAG regimen in patients who had failed prior AML therapy. In this phase 2, single-arm study, r/r AML patients received azacitidine or decitabine plus CAG regimen with tislelizumab. Primary endpoints were efficacy (objective response rate [ORR]) and safety. Secondary endpoints included overall survival (OS), event-free survival (EFS) and duration of response (DOR). Statistical analyses were performed using Stata 14.0 and SPSS 20.0 software where P < 0.05 denoted significance. Twenty-seven patients were enrolled patients and completed 1 cycle, and 14 (51.9%) and 4 (14.8%) patients completed 2 and 3 cycles, respectively. ORR was 63% (14: complete remission [CR]/CR with incomplete hematologic recovery [CRi], 3: partial remission (PR), 10: no response [NR]). Median OS (mOS) and EFS were 9.7 and 9.2 months, respectively. With a median follow-up of 8.2 months (1.1-26.9), the mOS was not reached in responders (CR/CRi/PR) while it was 2.4 months (0.0-5.4) in nonresponders (P = 0.002). Grade 2-3 immune-related adverse events (irAEs) were observed in 4 (14.8%) patients and 3 nonresponders died of lung infection after treatment. Tislelizumab + HMA + CAG regimen showed improved outcomes in r/r AML patients with lower pretherapy leukemia burden. irAEs were mild and low-grade and higher pretherapy bone marrow CD4+ CD127+ PD-1+ T cells might serve as a predictor of treatment response.ClinicalTrials.gov identifier NCT04541277.


Assuntos
Inibidores de Checkpoint Imunológico , Leucemia Mieloide Aguda , Humanos , Decitabina , Inibidores de Checkpoint Imunológico/uso terapêutico , Citarabina/uso terapêutico , Resultado do Tratamento , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico
12.
Nat Immunol ; 12(6): 568-75, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21516111

RESUMO

Interleukin 17 (IL-17)-producing helper T cells (T(H)17 cells) require exposure to IL-23 to become encephalitogenic, but the mechanism by which IL-23 promotes their pathogenicity is not known. Here we found that IL-23 induced production of the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) in T(H)17 cells and that GM-CSF had an essential role in their encephalitogenicity. Our findings identify a chief mechanism that underlies the important role of IL-23 in autoimmune diseases. IL-23 induced a positive feedback loop whereby GM-CSF secreted by T(H)17 cells stimulated the production of IL-23 by antigen-presenting cells. Such cross-regulation of IL-23 and GM-CSF explains the similar pattern of resistance to autoimmunity when either of the two cytokines is absent and identifies T(H)17 cells as a crucial source of GM-CSF in autoimmune inflammation.


Assuntos
Encefalomielite Autoimune Experimental/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interleucina-1/farmacologia , Interleucina-23/farmacologia , Células Th17/efeitos dos fármacos , Animais , Anticorpos/imunologia , Anticorpos/farmacologia , Antígeno CD11c/imunologia , Antígeno CD11c/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Técnicas de Cocultura , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/imunologia , Feminino , Citometria de Fluxo , Glicoproteínas , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Interleucina-1beta/farmacologia , Interleucina-23/imunologia , Interleucina-23/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Glicoproteína Mielina-Oligodendrócito , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fragmentos de Peptídeos , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Fator de Crescimento Transformador beta/farmacologia
13.
BMC Cancer ; 23(1): 646, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37434111

RESUMO

BACKGROUND: The low level of circulating tumor DNA (ctDNA) in the blood is a well-known challenge for the application of liquid biopsies in early-stage non-small cell lung cancer (NSCLC) management. Studies of metastatic NSCLC indicate that ctDNA levels are associated with tumor metabolic activity as measured by 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET/CT). This study investigated this association in NSCLC patients considered for potentially curative treatment and explored whether the two methods provide independent prognostic information. METHOD: Patients with stage I-III NSCLC who had routinely undergone an 18F-FDG PET/CT scan and exploratory ctDNA analyses were included. Tumor glucose uptake was measured by maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) from the 18F-FDG PET/CT scans. ctDNA detectability and quantity, using variant allele frequency, were estimated by tumor-informed ctDNA analyses. RESULTS: In total, 63 patients (median age 70 years, 60% women, and 90% adenocarcinoma) were included. The tumor glucose uptake (SUVmax, MTV, and TLG) was significantly higher in patients with detectable ctDNA (n = 19, p < 0.001). The ctDNA quantity correlated with MTV (Spearman's ρ = 0.53, p = 0.021) and TLG (Spearman's ρ = 0.56, p = 0.013) but not with SUVmax (Spearman's ρ = 0.034, p = 0.15). ctDNA detection was associated with shorter OS independent of MTV (HR: 2.70, 95% CI: 1.07-6.82, p = 0.035) and TLG (HR: 2.63, 95% CI: 1.06-6.51, p = 0.036). Patients with high tumor glucose uptake and detectable ctDNA had shorter overall survival and progression-free survival than those without detectable ctDNA, though these associations were not statistically significant (p > 0.05). CONCLUSION: There was a positive correlation between plasma ctDNA quantity and MTV and TLG in early-stage NSCLC patients. Despite the correlation, the results indicated that ctDNA detection was a negative prognostic factor independent of MTV and TLG.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , DNA Tumoral Circulante , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Feminino , Idoso , Masculino , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/genética , DNA Tumoral Circulante/genética , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/genética , Tomografia por Emissão de Pósitrons , Glucose
14.
J Plant Res ; 136(1): 33-45, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36471197

RESUMO

Floral organ movements that ensure autonomous selfing are likely to occur in species that grow in habitats with pollinator scarcity and/or an unpredictable environment. Stamen curvature and temporal flower closure are two important floral behaviors that can influence plant pollination mode and reproductive success. However, both behaviors are rarely reported within a species, and little is known about how these two movements of floral organs ensure reproductive success in an unpredictable early spring environment with few pollinators. The aim of this study was to assess whether stamen curvature and temporal flower closure ensure successful reproduction of Leontice incerta in its cold desert habitat. Flowering phenology, floral traits, stamen curvature patterns and flower visitors were surveyed. The breeding system, capacity and timing for autonomous selfing were estimated by pollination manipulations. The timing of floral opening and closure, and benefits of temporal flower closure were determined. We found that flowering of L. incerta began in late March to early April in two populations in two years, and the yellow flowers had neither nectar nor scent. Floral visitation occurred very rarely, but bees (Colletes sp.) were potential pollinators. Fruit and seed set of open and bagged flowers did not differ significantly from that of self-pollinated or cross-pollinated flowers. However, removal of stamens significantly decreased seed set. Self-pollination occurs when the stamens curve and anthers touch the stigma autonomously, suggesting autonomous selfing assurance of seed production in this self-compatible species. Both fruit and seed set of flowers that were prevented from closing were significantly lower than those of control flowers and closed flowers treated with simulated rain treatment. Therefore, stamen curvature and temporal floral closure can ensure successful sexual reproduction of L. incerta in early spring in the cold desert, where lack of pollinators otherwise may lead to pollination failure.


Assuntos
Polinização , Reprodução , Animais , Abelhas , Flores , Néctar de Plantas , Ásia
15.
Acta Radiol ; 64(1): 228-236, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34964365

RESUMO

BACKGROUND: Measurement of bone mineral density (BMD) is the most important method to diagnose osteoporosis. However, current BMD measurement is always performed after a fracture has occurred. PURPOSE: To explore whether a radiomic model based on abdominal computed tomography (CT) can predict the BMD of lumbar vertebrae. MATERIAL AND METHODS: A total of 245 patients who underwent both dual-energy X-ray absorptiometry (DXA) and abdominal CT examination (training cohort, n = 196; validation cohort, n = 49) were included in our retrospective study. In total, 1218 image features were extracted from abdominal CT images for each patient. Combined with clinical information, three steps including least absolute shrinkage and selection operator (LASSO) regression were used to select key features. A two-tier stacking regression model with multi-algorithm fusion was used for BMD prediction, which can integrate the advantages of linear model and non-linear model. The prediction results of this model were compared with those using a single regressor. The degree-of-freedom adjusted coefficient of determination (Adjusted-R2), root mean square error (RMSE), and mean absolute error (MAE) were used to evaluate the regression performance. RESULTS: Compared with other regression methods, the two-tier stacking regression model has a higher regression performance, with Adjusted-R2, RMSE, and MAE of 0.830, 0.077, and 0.06, respectively. Pearson correlation analysis and Bland-Altman analysis showed that the BMD predicted by the model had a high correlation with the DXA results (r = 0.932, difference = -0.01 ± 0.1412 mg/cm2). CONCLUSION: Using radiomics, the BMD of lumbar vertebrae could be predicted from abdominal CT images.


Assuntos
Densidade Óssea , Osteoporose , Humanos , Estudos Retrospectivos , Osteoporose/diagnóstico por imagem , Absorciometria de Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Vértebras Lombares/diagnóstico por imagem
16.
J Med Internet Res ; 25: e48145, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38055317

RESUMO

BACKGROUND: Electronic health records (EHRs) in unstructured formats are valuable sources of information for research in both the clinical and biomedical domains. However, before such records can be used for research purposes, sensitive health information (SHI) must be removed in several cases to protect patient privacy. Rule-based and machine learning-based methods have been shown to be effective in deidentification. However, very few studies investigated the combination of transformer-based language models and rules. OBJECTIVE: The objective of this study is to develop a hybrid deidentification pipeline for Australian EHR text notes using rules and transformers. The study also aims to investigate the impact of pretrained word embedding and transformer-based language models. METHODS: In this study, we present a hybrid deidentification pipeline called OpenDeID, which is developed using an Australian multicenter EHR-based corpus called OpenDeID Corpus. The OpenDeID corpus consists of 2100 pathology reports with 38,414 SHI entities from 1833 patients. The OpenDeID pipeline incorporates a hybrid approach of associative rules, supervised deep learning, and pretrained language models. RESULTS: The OpenDeID achieved a best F1-score of 0.9659 by fine-tuning the Discharge Summary BioBERT model and incorporating various preprocessing and postprocessing rules. The OpenDeID pipeline has been deployed at a large tertiary teaching hospital and has processed over 8000 unstructured EHR text notes in real time. CONCLUSIONS: The OpenDeID pipeline is a hybrid deidentification pipeline to deidentify SHI entities in unstructured EHR text notes. The pipeline has been evaluated on a large multicenter corpus. External validation will be undertaken as part of our future work to evaluate the effectiveness of the OpenDeID pipeline.


Assuntos
Anonimização de Dados , Registros Eletrônicos de Saúde , Humanos , Austrália , Algoritmos , Hospitais de Ensino
17.
Mikrochim Acta ; 190(3): 108, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36867247

RESUMO

A fluorescence quenching enhanced immunoassay has been developed to achieve ultrasensitive recognition of human epididymal 4 (HE4) modifying the fluorescence quencher. The carboxymethyl cellulose sodium-functionalized Nb2C MXene nanocomposite (CMC@MXene) was firstly introduced to quench the fluorescence signal of the luminophore Tb-Norfloxacin coordination polymer nanoparticles (Tb-NFX CPNPs). The Nb2C MXene nanocomposite as fluorescent nanoquencher inhibits the electron transfer between Tb and NFX to quench the fluorescent signal by coordinating the strongly electronegative carboxyl group on CMC with Tb (III) of Tb-NFX complex. Simultaneously, due to the superior photothermal conversion capability of CMC@MXene, the fluorescence signal has been further weakened by the photothermal effect driven non-radiative decay of the excited state under near-infrared laser irradiation. The constructed fluorescent biosensor based on CMC@MXene probe finally realized the enhanced fluorescence quenching effect, and achieved ultra-high sensitivity and selective detection of HE4, exhibiting a wide linear relationship with HE4 concentration on the logarithmic axis in the range of 10-5 to 10 ng/mL and a low detection limit of 3.3 fg/mL (S/N = 3). This work not only provides an enhanced fluorescent signal quenching method for the detection of HE4, but also provides novel insights for the design of fluorescent sensor toward different biomolecules.


Assuntos
Carboximetilcelulose Sódica , Norfloxacino , Humanos , Fluorescência , Corantes , Raios Infravermelhos
18.
Mikrochim Acta ; 190(9): 372, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37648806

RESUMO

Based on the highly specific interaction between concanavalin A (Con A) and glucose (Glu), a competitive electrochemiluminescence (ECL) biosensor was constructed for ultrasensitive detection of Con A. Nanocomposites with excellent electrocatalytic and photothermal properties were obtained by covalently bonding zinc oxide quantum dots (ZnO QDs) to vanadium carbide MXene (V2C MXene) surfaces. The modification of ZnO QDs hinders the aggregation of V2C MXene and increases the catalytic activity of oxygen reduction reaction, thus amplifying the luminol cathodic emission. In addition, the excellent photothermal performance of the V2C MXene-ZnO QDs can convert light energy into heat energy under the irradiation of 808 nm near infrared laser, thus increasing the temperature of the reaction system and accelerating the electron transfer process to realize the synergistic amplified homogeneous ECL system. This innovative work not only enriches the fundamental research on multifunctional MXene nanomaterials for biosensing, but also provides an effective strategy for ECL signal amplification.


Assuntos
Técnicas Biossensoriais , Concanavalina A , Eletroquímica , Eletroquímica/métodos , Transdução de Sinais , Concanavalina A/análise , Nitritos/química , Elementos de Transição/química , Pontos Quânticos , Óxido de Zinco/química , Humanos , Soro/química
19.
Molecules ; 28(7)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37049903

RESUMO

To develop novel 2-cyanoacrylate derivatives with potential bioactivity, a number of 2-cyanoacrylate compounds, including substituted pyrazole or 1,2,3-triazole ring, were designed, prepared, and structurally detected by 1H NMR, 13C NMR, and elemental analysis. The biological assessment displayed that some designed compounds had significant herbicidal activities against Brassica juncea, Chenopodium serotinum, Rumex acetosa, Alopecurus aequalis, Polypogon fugax, and Poa annua at a dosage of 1500 g/ha. Furthermore, some derivatives still expressed satisfactory herbicidal activities against Brassica juncea, Chenopodium serotinum, and Rumex acetosa when the dosage was lowered to 150 g/ha, especially the inhibitory effects of compounds 9a, 9d, 9f, 9i, 10a, 10b, 10e, and 10n against Brassica juncea were all over 80%, compounds 9d, 9f, 9g, 9h, 9i, 10h, 10i, 10m, 10n, and 10o possessed more than 70% inhibition rates against Chenopodium serotinum, and compound 9d indicated 70% herbicidal activity against Rumex acetosa. These results provided an important basis for further design and discovery of biologically active 2-cyanoacrylate compounds.


Assuntos
Cianoacrilatos , Herbicidas , Herbicidas/química , Espectroscopia de Ressonância Magnética , Poaceae , Triazóis/química , Relação Estrutura-Atividade
20.
Chin Med Sci J ; 38(2): 77-93, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37263796

RESUMO

Background In mainland China, patients with neovascular age-related macular degeneration (nAMD) have approximately an 40% prevalence of polypoidal choroidal vasculopathy (PCV). This disease leads to recurrent retinal pigment epithelium detachment (PED), extensive subretinal or vitreous hemorrhages, and severe vision loss. China has introduced various treatment modalities in the past years and gained comprehensive experience in treating PCV.Methods A total of 14 retinal specialists nationwide with expertise in PCV were empaneled to prioritize six questions and address their corresponding outcomes, regarding opinions on inactive PCV, choices of anti-vascular endothelial growth factor (anti-VEGF) monotherapy, photodynamic therapy (PDT) monotherapy or combined therapy, patients with persistent subretinal fluid (SRF) or intraretinal fluid (IRF) after loading dose anti-VEGF, and patients with massive subretinal hemorrhage. An evidence synthesis team conducted systematic reviews, which informed the recommendations that address these questions. This guideline used the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach to assess the certainty of evidence and grade the strengths of recommendations. Results The panel proposed the following six conditional recommendations regarding treatment choices. (1) For patients with inactive PCV, we suggest observation over treatment. (2) For treatment-na?ve PCV patients, we suggest either anti-VEGF monotherapy or combined anti-VEGF and PDT rather than PDT monotherapy. (3) For patients with PCV who plan to initiate combined anti-VEGF and PDT treatment, we suggest later/rescue PDT over initiate PDT. (4) For PCV patients who plan to initiate anti-VEGF monotherapy, we suggest the treat and extend (T&E) regimen rather than the pro re nata (PRN) regimen following three monthly loading doses. (5) For patients with persistent SRF or IRF on optical coherence tomography (OCT) after three monthly anti-VEGF treatments, we suggest proceeding with anti-VEGF treatment rather than observation. (6) For PCV patients with massive subretinal hemorrhage (equal to or more than four optic disc areas) involving the central macula, we suggest surgery (vitrectomy in combination with tissue-plasminogen activator (tPA) intraocular injection and gas tamponade) rather than anti-VEGF monotherapy. Conclusions Six evidence-based recommendations support optimal care for PCV patients' management.


Assuntos
Inibidores da Angiogênese , Vasculopatia Polipoidal da Coroide , Humanos , Inibidores da Angiogênese/uso terapêutico , Terapia Combinada , Fator A de Crescimento do Endotélio Vascular , Hemorragia Retiniana/tratamento farmacológico , Tomografia de Coerência Óptica/métodos , Angiofluoresceinografia/métodos , Estudos Retrospectivos
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