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1.
Nat Commun ; 15(1): 6102, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39030211

RESUMEN

Visible-light photocatalysis has evolved as a powerful technique to enable controllable radical reactions. Exploring unique photocatalytic mode for obtaining new chemoselectivity and product diversity is of great significance. Herein, we present a photo-induced chemoselective 1,2-diheteroarylation of unactivated alkenes utilizing halopyridines and quinolines. The ring-fused azaarenes serve as not only substrate, but also potential precursors for halogen-atom abstraction for pyridyl radical generation in this photocatalysis. As a complement to metal catalysis, this photo-induced radical process with mild and redox neutral conditions assembles two different heteroaryl groups into alkenes regioselectively and contribute to broad substrates scope. The obtained products containing aza-arene units permit various further diversifications, demonstrating the synthetic utility of this protocol. We anticipate that this protocol will trigger the further advancement of photo-induced alkyl/aryl halides activation.

2.
Prog Neurobiol ; 240: 102656, 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39009108

RESUMEN

The orientation map is one of the most well-studied functional maps of the visual cortex. However, results from the literature are of different qualities. Clear boundaries among different orientation domains and blurred uncertain distinctions were shown in different studies. These unclear imaging results will lead to an inaccuracy in depicting cortical structures, and the lack of consideration in experimental design will also lead to biased depictions of the cortical features. How we accurately define orientation domains will impact the entire field of research. In this study, we test how spatial frequency (SF), stimulus size, location, chromatic, and data processing methods affect the orientation functional maps (including a large area of dorsal V4, and parts of dorsal V1) acquired by intrinsic signal optical imaging. Our results indicate that, for large imaging fields, large grating stimuli with mixed SF components should be considered to acquire the orientation map. A diffusion model image enhancement based on the difference map could further improve the map quality. In addition, the similar outcomes of achromatic and chromatic gratings indicate two alternative types of afferents from LGN, pooling in V1 to generate cue-invariant orientation selectivity.

3.
Pest Manag Sci ; 80(8): 3808-3814, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38507262

RESUMEN

BACKGROUND: Insects mainly rely on innate immunity against pathogen infection. Plagiodera versicolora (Coleoptera: Chrysomelidae), is a worldwide leaf-eating forest pest in salicaceous trees. However, the mechanisms behind the immunodeficiency pathway (IMD) remain poorly understood. RESULTS: In this study, we obtained a Relish gene from transcriptome analysis. Tissue and instar expression profiles were subsequently obtained using quantitative real-time polymerase chain reaction analysis. The results showed that Relish has high expression levels in eggs, larvae and adults, and especially in fat bodies. Transcripts of the tested antimicrobial peptides (AMPs), defensin1, defensin2 and attacin2 were downregulated by dsRelish. Knockdown of Relish led to greater mortality in larvae after Staphylococcus aureus infection. In addition, we performed bacterial 16S ribosomal RNA-based high-throughput sequencing. The results showed that the relative abundance of some gut bacteria was significantly altered after dsRelish ingestion. CONCLUSION: This study provides a greater understanding of the IMD signaling pathway, facilitating functional studies of Relish in P. versicolora. Moreover, a genetic pest management technique might be developed using Relish as a lethal gene to control the pest P. versicolora. © 2024 Society of Chemical Industry.


Asunto(s)
Escarabajos , Proteínas de Insectos , Larva , Animales , Escarabajos/inmunología , Escarabajos/microbiología , Escarabajos/fisiología , Larva/crecimiento & desarrollo , Larva/inmunología , Larva/microbiología , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Inmunidad Innata
4.
Ying Yong Sheng Tai Xue Bao ; 33(10): 2670-2678, 2022 Oct.
Artículo en Chino | MEDLINE | ID: mdl-36384601

RESUMEN

In order to understand the interspecific and ecological relationships of Michelia odora (extremely small population) community and strengthen the protection of wild M. odora resources in Junzifeng Nature Reserve, we studied the niche characteristics and interspecific associations of dominant tree species. The results showed that M. odora, Machilus chekiangensis, Schima superba, and Alniphyllum fortunei had obvious niche breadth advantages, which were the constructive species of the community. Among the 190 groups of species pairs among the 20 dominant tree species, 50.5% of species pairs had niche overlap value greater than 0.5. The degree of ecological niche differentiation among species was general. M. odora had large niche overlap with other 19 species, indicating a competitive risk when resources were insufficient. The overall associations of dominant tree species were significantly positive, indicating the community was at the late stage of relatively stable succession. The results ofχ2 test, asso-ciation coefficient, and Pearson correlation coefficient showed that all the significance ratios of interspecific association were lower, and that the independence among species was relatively strong. There was a positive correlation between interspecific association and niche overlap. The M. odora community was relatively mature, with full utilization of resources and stable interspecific relationship. To promote the rejuvenation and create a good habitat of M. odora population, the population size with large overlap with M. odora niche and significant negative association could be appropriately limited, while that with positive interaction could be increased.


Asunto(s)
Magnoliaceae , Theaceae , Árboles , Ecosistema , Densidad de Población
5.
J Bone Miner Metab ; 39(6): 1058-1065, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34392464

RESUMEN

INTRODUCTION: Neutrophil gelatinase-associated lipocalin (NGAL) is not only a biomarker of kidney injury but also a bone-derived factor involved in metabolism. We aimed to explore relationships between plasma NGAL and chronic kidney disease-mineral bone disorder (CKD-MBD) parameters in maintenance hemodialysis (MHD) patients. MATERIALS AND METHODS: First, a cross sectional observational study, including 105 MHD patients, was conducted to explore relationships between plasma NGAL levels and CKD-MBD parameters. Second, impact of parathyroidectomy and auto-transplantation (PTX + AT) on plasma NGAL was investigated in 12 MHD patients with severe secondary hyperparathyroidism (SHPT). RESULTS: According to Spearman correlation analysis, plasma NGAL levels were positively correlated with female (r = 0.243, P = 0.012), vintage (r = 0.290, P = 0.003), Klotho (r = 0.234, P = 0.016), calcium(Ca) (r = 0.332, P = 0.001), alkaline phosphatase (ALP) (r = 0.401, P < 0.001) and intact parathyroid hormone (iPTH) (r = 0.256, P = 0.008); while inversely correlated with albumin(Alb) (r = - 0.201, P = 0.039). After adjusting for age, sex, vintage, Alb and all parameters of CKD-MBD(Ca, P, lg(ALP), lg(iPTH), Klotho and fibroblast growth factor 23(FGF23)), lg(NGAL) were positively correlated with Ca (r = 0.481, P < 0.001), P (r = 0.336, P = 0.037), lg(ALP) (r = 0.646, P < 0.001) in Partial correlation analysis; further multiple linear regression analysis showed same positive associations between lg(NGAL) and Ca (ß = 0.330, P = 0.002), P (ß = 0.218, P = 0.037), lg(ALP) (ß = 0.671, P < 0.001). During the 4-7 days after PTX + AT, plasma NGAL decreased from 715.84 (578.73, 988.14) to 688.42 (660.00, 760.26) ng/mL (P = 0.071), Klotho increased from 496.45 (341.73, 848.30) to 1138.25 (593.87, 2009.27) pg/mL (P = 0.099). CONCLUSION: Plasma NGAL levels were positively associated with ALP in MHD patients; and downtrends were shown after PTX + AT in patients with severe SHPT. These findings suggest that NGAL is a participant in CKD-MBD under MHD condition.


Asunto(s)
Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica , Lipocalina 2/sangre , Insuficiencia Renal Crónica , Biomarcadores , Estudios Transversales , Femenino , Factor-23 de Crecimiento de Fibroblastos , Humanos , Diálisis Renal , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/terapia
6.
World J Clin Cases ; 8(24): 6252-6263, 2020 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-33392306

RESUMEN

BACKGROUND: Understanding a virus shedding patterns in body fluids/secretions is important to determine the samples to be used for diagnosis and to formulate infection control measures. AIM: To investigate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) shedding patterns and its risk factors. METHODS: All laboratory-confirmed coronavirus disease 2019 patients with complete medical records admitted to the Shenzhen Third People's Hospital from January 28, 2020 to March 8, 2020 were included. Among 145 patients (54.5% males; median age, 46.1 years), three (2.1%) died. The bronco-alveolar lavage fluid (BALF) had the highest virus load compared with the other samples. The viral load peaked at admission (3.3 × 108 copies) and sharply decreased 10 d after admission. RESULTS: The viral load was associated with prolonged intensive care unit (ICU) duration. Patients in the ICU had significantly longer shedding time compared to those in the wards (P < 0.0001). Age > 60 years [hazard ratio (HR) = 0.6; 95% confidence interval (CI): 0.4-0.9] was an independent risk factor for SARS-CoV-2 shedding, while chloroquine (HR = 22.8; 95%CI: 2.3-224.6) was a protective factor. CONCLUSION: BALF had the highest SARS-CoV-2 load. Elderly patients had higher virus loads, which was associated with a prolonged ICU stay. Chloroquine was associated with shorter shedding duration and increased the chance of viral negativity.

7.
Artif Intell Med ; 99: 101694, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31606108

RESUMEN

Diabetic retinopathy (DR) is the most common cause of blindness in middle-age subjects and low DR screening rates demonstrates the need for an automated image assessment system, which can benefit from the development of deep learning techniques. Therefore, the effective classification performance is significant in favor of the referable DR identification task. In this paper, we propose a new strategy, which applies multiple weighted paths into convolutional neural network, called the WP-CNN, motivated by the ensemble learning. In WP-CNN, multiple path weight coefficients are optimized by back propagation, and the output features are averaged for redundancy reduction and fast convergence. The experiment results show that with the efficient training convergence rate WP-CNN achieves an accuracy of 94.23% with sensitivity of 90.94%, specificity of 95.74%, an area under the receiver operating curve of 0.9823 and F1-score of 0.9087. By taking full advantage of the multipath mechanism, the proposed WP-CNN is shown to be accurate and effective for referable DR identification compared to the state-of-art algorithms.


Asunto(s)
Retinopatía Diabética/diagnóstico , Retinopatía Diabética/patología , Diagnóstico por Computador/métodos , Redes Neurales de la Computación , Aprendizaje Profundo , Retinopatía Diabética/diagnóstico por imagen , Fondo de Ojo , Humanos , Curva ROC , Sensibilidad y Especificidad
8.
Environ Monit Assess ; 165(1-4): 295-305, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19440848

RESUMEN

A field campaign was conducted to measure and analyze 13 polycyclic aromatic hydrocarbons (PAHs) in six major zones in the city of Shanghai, P.R. China from August 2006 to April 2007. Ambient air samples were collected seasonally using passive air samplers, and gas chromatography-mass spectroscopy was used in this field campaign. The results showed that there was a sequence of 13 PAHs at Phen > FA > Pyr > Chr > Fl > An > BaA > BbFA > BghiP > IcdP > BkFA > BaP > DahA and the sum of these PAHs is 36.01 +/- 10.85 ng/m(3) in gas phase. FL, Phen, FA, Pyr, and Chr were the dominant PAHs in gas phase in the city. They contributed 90% of total PAHs in the gas phase. Proportion of measured PAHs with three, four, five, and six rings to total PAHs was 53%, 42%, 3%, and 2%, respectively. The highest concentration of SigmaPAHs (the sum of 13 PAHs) occurred in the wintertime and the lowest was in the summer. This investigation suggested that traffic, wood combustion, and metal scrap burn emissions were dominant sources of the concentrations of PAHs in six city zones compared with coal burning and industry emissions. Further, the traffic emission sources of PAHs in the city were attributed mostly to gasoline-powered vehicles compared with diesel-powered vehicles. It was revealed that the seasonal changes in PAHs in the city depended on different source types. Metal scrap burn was found to be the major source of PAHs during the autumn, while the PAH levels in the atmosphere for winter and spring seasons were mainly influenced by wood and biomass combustion. Comparisons of PAHs among different city zones and with several other cities worldwide were also made and discussed.


Asunto(s)
Contaminantes Atmosféricos/análisis , Exposición a Riesgos Ambientales/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Población Urbana , China , Monitoreo del Ambiente/métodos
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