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1.
Plant Cell ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630900

RESUMO

Cucumber (Cucumis sativus, Cs) tendrils are slender vegetative organs that typically require manual removal to ensure orderly growth during greenhouse cultivation. Here, we identified cucumber tendril-less (tl), a Tnt1 retrotransposon-induced insertion mutant lacking tendrils. Map-based cloning identified the mutated gene, CsaV3_3G003590, which we designated as CsTL, which is homologous to Arabidopsis thaliana LATERAL SUPPRESSOR (AtLAS). Knocking out CsTL repressed tendril formation but did not affect branch initiation, whereas overexpression of CsTL resulted in the formation of two or more tendrils in one leaf axil. Although expression of two cucumber genes regulating tendril formation, Tendril (CsTEN) and Unusual Floral Organs (CsUFO), was significantly decreased in CsTL knockout lines, these two genes were not direct downstream targets of CsTL. Instead, CsTL physically interacted with CsTEN, an interaction that further enhanced CsTEN-mediated expression of CsUFO. In Arabidopsis, the CsTL homolog AtLAS acts upstream of REVOLUTA (REV) to regulate branch initiation. Knocking out cucumber CsREV inhibited branch formation without affecting tendril initiation. Furthermore, genomic regions containing CsTL and AtLAS were not syntenic between the cucumber and Arabidopsis genomes, whereas REV orthologs were found on a shared syntenic block. Our results revealed not only that cucumber CsTL possesses a divergent function in promoting tendril formation but also that CsREV retains its conserved function in shoot branching.

2.
BMC Plant Biol ; 24(1): 677, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39014327

RESUMO

Climate change is predicted to increase the occurrence of extreme weather events such as heatwaves, which may thereby impact the outcome of plant-herbivore interactions. While elevated temperature is known to directly affect herbivore growth, it remains largely unclear if it indirectly influences herbivore performance by affecting the host plant they feed on. In this study, we investigated how transient exposure to high temperature influences plant herbivory-induced defenses at the transcript and metabolic level. To this end, we studied the interaction between potato (Solanum tuberosum) plants and the larvae of the potato tuber moth (Phthorimaea operculella) under different temperature regimes. We found that P. operculella larvae grew heavier on leaves co-stressed by high temperature and insect herbivory than on leaves pre-stressed by herbivory alone. We also observed that high temperature treatments altered phylotranscriptomic patterns upon herbivory, which changed from an evolutionary hourglass pattern, in which transcriptomic responses at early and late time points after elicitation are more variable than the ones in the middle, to a vase pattern. Specifically, transcripts of many herbivory-induced genes in the early and late defense stage were suppressed by HT treatment, whereas those in the intermediate stage peaked earlier. Additionally, we observed that high temperature impaired the induction of jasmonates and defense compounds upon herbivory. Moreover, using jasmonate-reduced (JA-reduced, irAOC) and -elevated (JA-Ile-elevated, irCYP94B3s) potato plants, we showed that high temperature suppresses JA signaling mediated plant-induced defense to herbivore attack. Thus, our study provides evidences on how temperature reprograms plant-induced defense to herbivores.


Assuntos
Resposta ao Choque Térmico , Herbivoria , Larva , Mariposas , Solanum tuberosum , Solanum tuberosum/fisiologia , Solanum tuberosum/parasitologia , Solanum tuberosum/genética , Solanum tuberosum/imunologia , Animais , Mariposas/fisiologia , Larva/fisiologia , Regulação da Expressão Gênica de Plantas , Folhas de Planta/fisiologia , Folhas de Planta/parasitologia , Temperatura Alta , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Defesa das Plantas contra Herbivoria , Transcriptoma , Mudança Climática
3.
Plant Physiol ; 193(4): 2592-2604, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37584314

RESUMO

The lateral organs of watermelon (Citrullus lanatus), including lobed leaves, branches, flowers, and tendrils, together determine plant architecture and yield. However, the genetic controls underlying lateral organ initiation and morphogenesis remain unclear. Here, we found that knocking out the homologous gene of shoot branching regulator LATERAL SUPPRESSOR in watermelon (ClLs) repressed the initiation of branches, flowers, and tendrils and led to developing round leaves, indicating that ClLs undergoes functional expansion compared with its homologs in Arabidopsis (Arabidopsis thaliana), rice (Oryza sativa), and tomato (Solanum lycopersicum). Using ClLs as the bait to screen against the cDNA library of watermelon, we identified several ClLs-interacting candidate proteins, including TENDRIL (ClTEN), PINOID (ClPID), and APETALA1 (ClAP1). Protein-protein interaction assays further demonstrated that ClLs could directly interact with ClTEN, ClPID, and ClAP1. The mRNA in situ hybridization assay revealed that the transcriptional patterns of ClLs overlapped with those of ClTEN, ClPID, and ClAP1 in the axillary meristems and leaf primordia. Mutants of ClTEN, ClPID, and ClAP1 generated by the CRISPR/Cas9 gene editing system lacked tendrils, developed round leaves, and displayed floral diapause, respectively, and all these phenotypes could be observed in ClLs knockout lines. Our findings indicate that ClLs acts as lateral organ identity protein by forming complexes with ClTEN, ClPID, and ClAP1, providing several gene targets for transforming the architecture of watermelon.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Citrullus , Citrullus/genética , Arabidopsis/genética , Meristema/genética , Proteínas de Arabidopsis/metabolismo , Morfogênese , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
J Exp Bot ; 75(1): 483-499, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37781866

RESUMO

DNA demethylase (DML) is involved in plant development and responses to biotic and abiotic stresses; however, its role in plant-herbivore interaction remains elusive. Here, we found that herbivory by the potato tuber moth, Phthorimaea operculella, rapidly induced the genome-wide DNA methylation and accumulation of DML gene transcripts in potato plants. Herbivory induction of DML transcripts was suppressed in jasmonate-deficient plants, whereas exogenous application of methyl jasmonate (MeJA) improved DML transcripts, indicating that the induction of DML transcripts by herbivory is associated with jasmonate signaling. Moreover, P. operculella larvae grew heavier on DML gene (StDML2) knockdown plants than on wild-type plants, and the decreased biosynthesis of jasmonates in the former may be responsible for this difference, since the larvae feeding on these two genotypes supplemented with MeJA showed similar growth. In addition, P. operculella adult moths preferred to oviposit on StDML2 knockdown plants than on wild-type plants, which was associated with the reduced emission of ß-caryophyllene in the former. In addition, supplementing ß-caryophyllene to these two genotypes further disrupted moths' oviposit choice preference for them. Interestingly, in StDML2 knockdown plants, hypermethylation was found at the promoter regions for the key genes StAOS and StAOC in the jasmonate biosynthetic pathway, as well as for the key gene StTPS12 in ß-caryophyllene production. Our findings suggest that knocking down StDML2 can affect herbivore defense via jasmonate signaling and defense compound production in potato plants.


Assuntos
Mariposas , Solanum tuberosum , Animais , Herbivoria , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Insetos , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Mariposas/genética , Mariposas/metabolismo , Larva , DNA
5.
Chemistry ; 30(17): e202400084, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38228507

RESUMO

Secondary metabolites that have the same biological origin must share some relationship in their biosynthesis. Exploring this relationship has always been a significant task for synthetic biologists. However, from the perspective of synthetic chemists, it is equally important to propose, prove, or refute potential biosynthetic pathways in order to elucidate and understand the biosynthesis of homologous secondary metabolites. In this study, driven by the high structural similarity between the homologous Ganoderma meroterpenoids cochlearol B and ganocin B, two chemically synthetic strategies were designed and investigated sequentially for the synthesis of cochlearol B from ganocin B. These strategies include intramolecular metal-catalyzed hydrogen atom transfer (MHAT) and intramolecular photochemical [2+2] cycloaddition. The aim was to reveal their potential biosynthetic conversion relationship using chemical synthesis methods. As a result, a highly efficient total synthesis of cochlearol B, cochlearol T, cochlearol F, as well as the formal total synthesis of ganocins A-B, and ganocochlearins C-D, has been achieved. Additionally, a novel synthetic approach for the synthesis of 6,6-disubstituted 6H-dibenzo[b,d]pyran and its analogues has been developed through palladium(II)-catalyzed Wacker-type/cross-coupling cascade reactions.


Assuntos
Ganoderma , Ganoderma/química , Terpenos/química , Metais , Hidrogênio
6.
Appl Opt ; 63(1): 10-16, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175000

RESUMO

The intragenerational mutation of the genetic algorithm (IMGA) is proposed to actively broaden the searching space during the optimization process. The searching space is aggressively increased by expanding the variation of mutation rates of all individuals within each generation, leading to the reduction of the required number of iterations, improving the convergence speed and the enhancement factor.

7.
BMC Med Imaging ; 24(1): 19, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238662

RESUMO

BACKGROUND: Human vision has inspired significant advancements in computer vision, yet the human eye is prone to various silent eye diseases. With the advent of deep learning, computer vision for detecting human eye diseases has gained prominence, but most studies have focused only on a limited number of eye diseases. RESULTS: Our model demonstrated a reduction in inherent bias and enhanced robustness. The fused network achieved an Accuracy of 0.9237, Kappa of 0.878, F1 Score of 0.914 (95% CI [0.875-0.954]), Precision of 0.945 (95% CI [0.928-0.963]), Recall of 0.89 (95% CI [0.821-0.958]), and an AUC value of ROC at 0.987. These metrics are notably higher than those of comparable studies. CONCLUSIONS: Our deep neural network-based model exhibited improvements in eye disease recognition metrics over models from peer research, highlighting its potential application in this field. METHODS: In deep learning-based eye recognition, to improve the learning efficiency of the model, we train and fine-tune the network by transfer learning. In order to eliminate the decision bias of the models and improve the credibility of the decisions, we propose a model decision fusion method based on the D-S theory. However, D-S theory is an incomplete and conflicting theory, we improve and eliminate the existed paradoxes, propose the improved D-S evidence theory(ID-SET), and apply it to the decision fusion of eye disease recognition models.


Assuntos
Aprendizado Profundo , Oftalmopatias , Humanos , Redes Neurais de Computação
8.
Horm Metab Res ; 55(2): 124-135, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36216243

RESUMO

As a major cause of mortality, cardiovascular disease is associated with obesity and diabetes. However, the molecular mechanism by which diabetes-obesity causes cardiovascular complications is largely unknown. In this study, the crosstalk mediated by 3T3-L1 preadipocytes and mouse retina microvascular endothelial cells (mRMECs) was determined after co-culturing performed with a Transwell system or measuring exosome uptake by mRMECs. CCK-8 assays, EdU incorporation assays, TUNEL staining, and ELISAs were used to evaluate the functions of mRMECs. Related protein markers were analyzed by western blotting. Our results showed that LINC00968 levels were significantly elevated in the exosomes derived from H-Glu-induced 3T3-L1 preadipocytes. Both H-Glu treatment and co-culture with 3T3-L1 cells damaged mRMECs, as indicated by lower rates of proliferation and higher rates of apoptosis and cell adhesion molecule expression, as well as by induced inflammation and oxidative stress, which were enhanced by combined H-Glu and co-culture treatment. Furthermore, H-Glu and co-culture treatment increased LINC00968 expression in mRMECs, and the exosomes collected from 3T3-L1 cells had a similar effect. Functionally, LINC00968 inhibition protected mRMECs against the effects of H-Glu and co-culture treatment, while LINC00968 played the opposite role. LINC00968 was found to target miR-361-5p, and TRAF3 was identified as a target gene of miR-361-5p. Finally, miR-361-5p overexpression alleviated the effects of LINC00968 on H-Glu-induced mRMEC dysfunction in vitro. In conclusion, our results indicated that in an H-glu environment, adipocyte exosomes damage microvascular endothelial cells via a LINC00968/miR-361-5p/TRAF3 signaling pathway, which could possibly serve as a target for treating diabetes-obesity-triggered microvascular complications.


Assuntos
MicroRNAs , Camundongos , Animais , MicroRNAs/metabolismo , Fator 3 Associado a Receptor de TNF/metabolismo , Células Endoteliais/metabolismo , Adipócitos/metabolismo , Glucose/farmacologia , Glucose/metabolismo , Retina/metabolismo
9.
J Surg Res ; 282: 101-108, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36265429

RESUMO

INTRODUCTION: Most microsurgical procedures require the surgeon to use tools to grasp and hold fragile objects in the surgical site. Prior research on grasping in surgery has mostly either been in other surgical techniques or used grasping as an auxiliary metric. We focus on microsurgery and investigate what grasping can tell about microsurgical skill and suturing performance. This study lays groundwork for using automatic detection of grasps to evaluate surgical skill. METHODS: Five expert surgeons and six novices completed sutures on a microsurgical training board. Video recordings of the performance were annotated for the number of grasps, while an eye tracker recorded the participants' pupil dilations for cognitive workload assessment. Performance was measured with suturing duration and the University of Western Ontario Microsurgical Skills Assessment instrument (UWOMSA). Differences in skill, suturing performance and cognitive workload were compared with grasping behavior. RESULTS: Novices needed significantly more grasps to complete sutures and failed to grasp more often than the experts. The number of grasps affected the suturing duration more in novices. Decreasing suturing efficiency as measured by UWOMSA instrument was associated with increase in grasps, even when we controlled for overall skill differences. Novices displayed larger pupil dilations when averaged over a sufficiently large sample, and the difference increased after the grasp. CONCLUSIONS: Grasping action during microsurgical procedures can be used as a conceptually simple yet objective proxy in microsurgical performance assessment. If the grasps could be detected automatically, they could be used to aid in computational evaluation of surgical trainees' performance.


Assuntos
Competência Clínica , Cirurgiões , Humanos , Suturas , Microcirurgia , Força da Mão
10.
Surg Endosc ; 37(11): 8601-8610, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37491659

RESUMO

BACKGROUND: Obesity is a chronic and progressive disease associated with significant morbidity, mortality, and health-care costs. Bariatric surgery is the most effective intervention for sustainable weight loss and resolution of obesity-related comorbidities. Studies examining comorbidity resolution largely rely on individual self-reported outcomes and electronic record reviews. We present a population-based study looking at prescription medication utilization before and after bariatric surgery as a measure of comorbidity resolution. METHODS: All patients enrolled in the Center for Metabolic and Bariatric Surgery who underwent either gastric bypass or sleeve gastrectomy between 2013 and 2019 in Manitoba were included. Demographic information, follow up, and outpatient prescription dispensation data were obtained from the Manitoba Population Research Data Repository housed at the Manitoba Centre for Health Policy for 5 years pre- and post-surgery. RESULTS: A total of 1184 patients were included. Antidepressants and selective serotonin reuptake inhibitors were the most commonly prescribed classes, and along with thyroid medication, utilization remained stable after bariatric surgery. Proton pump inhibitors and opioid class drugs increased at 1 year after surgery then returned to baseline. Glucose and lipid-lowering medications, including statins, biguanides, sulfonylureas, and insulin, were decreased. Antihypertensives, including ACE inhibitors, calcium channel blockers, angiotensin receptors blockers, thiazides, and beta blockers, similarly decreased. CONCLUSION: This is the first Canadian study employing a provincial-wide prescription database to measure long-term comorbidity resolution after bariatric surgery. The use of administrative data eliminates potential biases and inaccuracies in follow up and self-reported outcomes. Consistent with the literature, prescriptions for the treatment of metabolic syndrome all decreased and were sustained at long-term follow up. Further studies are needed to delineate the effects of altered pharmaceutical utilization on patient quality of life and health-care expenditures.


Assuntos
Cirurgia Bariátrica , Derivação Gástrica , Obesidade Mórbida , Medicamentos sob Prescrição , Humanos , Obesidade Mórbida/cirurgia , Qualidade de Vida , Estudos de Coortes , Canadá , Obesidade/complicações , Obesidade/cirurgia , Obesidade/epidemiologia , Comorbidade , Prescrições , Gastrectomia , Resultado do Tratamento , Estudos Retrospectivos
11.
Biochem Genet ; 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38095736

RESUMO

Colorectal cancer (CRC) is one of the most prevalent and life-threatening cancers. Rapid cell proliferation is the leading cause of cancer-related death in CRC. MicroRNAs (miRNAs) have been identified to play essential roles in the proliferation of CRC. Differential expression of let-7c-5p in CRC was assessed using a GEO dataset, and confirmed through RT-qPCR using CRC subject tissues. Let-7c-5p-overexpressing HCT8 cell line was constructed by transfecting let-7c-5p. Bioinformatics analysis identified that DUSP7 is the target gene of let-7c-5p. Further experimental assays, including Cell Counting Kit-8 (CCK8), EdU staining, cell colony, and Western Blot assays, confirmed the target genes and pathway of let-7c-5p. Receiver operator characteristic curve (ROC) analysis was performed to evaluate the diagnostic value of let-7c-5p for CRC. Finally, survival analysis was performed to determine the effect of DUSP7 and let-7c-5p on the prognosis of CRC patients. RT-qPCR analysis showed that the expression level of let-7c-5p was significantly increased in CRC subject tissues compared to the adjacent tissue. Overexpression of let-7c-5p promoted cell proliferation in HCT8 cell line. Furthermore, the MAPK-ERK pathway's protein expression of p-ERK1/2 was downregulated, while the ratio of Bcl-2/Bax was increased by let-7c-5p transfection in HCT 8. ROC analysis demonstrated that the expressive level of let-7c-5p had higher diagnostic value for CRC. Survival curve analysis indicated that high expression of DUSP7 and low expression of let-7c-5p were associated with poor prognosis in CRC patients. The findings suggest that let-7c-5p exerts an antitumor function by inhibiting the DUSP7-mediated MAPK-ERK pathway. Both DUSP7 and let-7c-5p have the potential to serve as prognostic biomarkers in CRC patients.

12.
Int Ophthalmol ; 43(7): 2203-2214, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36595127

RESUMO

PURPOSE: Fungal keratitis is a common cause of blindness worldwide. Timely identification of the causative fungal genera is essential for clinical management. In vivo confocal microscopy (IVCM) provides useful information on pathogenic genera. This study attempted to apply deep learning (DL) to establish an automated method to identify pathogenic fungal genera using IVCM images. METHODS: Deep learning networks were trained, validated, and tested using a data set of 3364 IVCM images that collected from 100 eyes of 100 patients with culture-proven filamentous fungal keratitis. Two transfer learning approaches were investigated: one was a combined framework that extracted features by a DL network and adopted decision tree (DT) as a classifier; another was a complete supervised DL model which used DL-based fully connected layers to implement the classification. RESULTS: The DL classifier model revealed better performance compared with the DT classifier model in an independent testing set. The DL classifier model showed an area under the receiver operating characteristic curves (AUC) of 0.887 with an accuracy of 0.817, sensitivity of 0.791, specificity of 0.831, G-mean of 0.811, and F1 score of 0.749 in identifying Fusarium, and achieved an AUC of 0.827 with an accuracy of 0.757, sensitivity of 0.756, specificity of 0.759, G-mean of 0.757, and F1 score of 0.716 in identifying Aspergillus. CONCLUSION: The DL model can classify Fusarium and Aspergillus by learning effective features in IVCM images automatically. The automated IVCM image analysis suggests a noninvasive identification of Fusarium and Aspergillus with clear potential application in early diagnosis and management of fungal keratitis.


Assuntos
Úlcera da Córnea , Infecções Oculares Fúngicas , Ceratite , Humanos , Inteligência Artificial , Úlcera da Córnea/diagnóstico , Ceratite/diagnóstico , Ceratite/microbiologia , Fungos , Infecções Oculares Fúngicas/diagnóstico , Infecções Oculares Fúngicas/microbiologia , Microscopia Confocal/métodos
13.
Inflamm Res ; 71(4): 397-407, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35275225

RESUMO

PURPOSE: Our study aimed to investigate the function of Cavin-1 and SOCS3 in macrophages/microglia M2 polarization and further explored the relevant mechanism. METHODS: Expression levels of Cavin-1 and SOCS3 in macrophages/microglia were measured by western blotting and RT-PCR, respectively. Then, Cavin-1 or SOCS3 was gene silenced by a siRNA approach, and gene silencing efficiency was determined by western blotting. Next, co-immunoprecipitation (Co-IP) was employed to further analyze the interaction between Cavin-1 and SOCS3. Finally, the activation of STAT6/PPAR-γ signaling was evaluated using western blotting, and the M2 macrophages/microglia polarization was validated by measuring the mRNA expression of M2 markers by RT-PCR. RESULTS: In the polarization process of macrophages/microglia to M2 phenotype, both Cavin-1 and SOCS3 increased synchronously at protein and mRNA level, reached the peak at the 6 h, and then decreased. After Cavin-1 or SOCS3 silencing, the expression of Cavin-1 and SOCS3 declined. These results suggested that Cavin-1 and SOCS3 were positively correlated in macrophages/microglia, and this conjecture was verified by Co-IP. Besides, Cavin-1 silencing not only suppressed the activation of STAT6/PPAR-γ pathway, but also suppressed the release of anti-inflammatory factors. Finally, we found that SOCS3 overexpression reversed the inhibitory effect of Cavin-1 silencing on the release of anti-inflammatory factors in M2 macrophages/microglia. CONCLUSIONS: Cavin-1 and SOCS3 are actively involved in the process of M2 macrophages/microglia polarization. As a SOCS3 interacting protein, Cavin-1 can promote M2 macrophages/microglia polarization via SOCS3.


Assuntos
Microglia , Receptores Ativados por Proliferador de Peroxissomo , Anti-Inflamatórios/farmacologia , Macrófagos , Microglia/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , RNA Mensageiro/metabolismo
14.
Int J Food Sci Nutr ; 73(6): 786-799, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35603582

RESUMO

The effect of tea polyphenols (TPs) on noodles quality was investigated, and the interaction mechanism between catechins and gliadins was explored. With TPs addition, noodles showed the significant changes in physicochemical and sensory properties. The water absorption, tensile strength and elasticity increased by 1.35%, 4.98%, 28.51% with 0.5% of TPs, and then decreased with the increasing of TPs. According to the determinations of surface hydrophobicity, spatial structure, thermal properties, amidogen and sulfhydryl content, the structure and properties of gliadin were affected by catechins. Esterified catechins tended to disrupt gliadin structures and non-esterified catechins polymerised gliadin molecules. Furthermore, molecular docking results indicated that catechins interacted with gliadin mainly by hydrogen bonds and hydrophobic action. The reactivity of catechins with gliadin was in the sequence as: epigallocatechin gallate > epicatechin gallate > epigallocatechin > epicatechin, which was based on the account of gallate and B-ring hydroxyl number discrepancy. All results suggested that catechins affected greatly on gliadin, and TPs were potentially used to improve the quality of flour products.


Assuntos
Catequina , Polifenóis , Catequina/química , Gliadina , Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Polifenóis/farmacologia , Chá/química
15.
Angew Chem Int Ed Engl ; 61(9): e202112439, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-34981638

RESUMO

Absolute control over polymer stereo- and sequence structure is highly challenging in polymer chemistry. Here, an acid-orthogonal deprotection strategy is proposed for the iterative synthesis of a family of unimolecular polymers starting with enantiopure serines, featuring precise sequence, stereoconfiguration and side-chain functionalities that cannot be achieved using traditional polymerization techniques. Acid-orthogonal deprotections proceed independently of one another by the selection of protecting groups that feature the respective acid-lability. Under p-toluenesulfonic acid, acidolysis of tert-butyloxycarbonyl can proceed exclusively, while low-dosage trifluoroacetic acid and low temperature only trigger the selective and quantitative cleavage of trityl. The pioneering use of this acid-orthogonal deprotection chemistry increases the compatibility with otherwise sensitive groups and opens up pathways to facilely introduce structural and functional diversity into stereo- and sequence-defined polymers, thus imparting their unique properties beyond natural biopolymers.

16.
Phys Rev Lett ; 126(14): 146802, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33891442

RESUMO

Recently, a new family of symmetry-protected higher-order topological insulators has been proposed and was shown to host lower-dimensional boundary states. However, with the existence of the strong disorder in the bulk, the crystal symmetry is broken, and the associated corner states are disappeared. It is well known that the emergence of robust edge states and quantized transport can be induced by adding sufficient disorders into a topologically trivial insulator, that is the so-called topological Anderson insulator. The question is whether disorders can also cause the higher-order topological phase. This is not known so far, because interactions between disorders and the higher-order topological phases are completely different from those with the first-order topological system. Here, we demonstrate theoretically that the disorder-induced higher-order topological corner state and quantized fraction corner charge can appear in a modified Haldane model. In experiments, we construct the classical analog of such higher-order topological Anderson insulators using electric circuits and observe the disorder-induced corner state through the voltage measurement. Our work defies the conventional view that the disorder is detrimental to the higher-order topological phase, and offers a feasible platform to investigate the interaction between disorders and higher-order topological phases.

17.
Sensors (Basel) ; 21(9)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922575

RESUMO

Hyperspectral LiDAR (HSL) is a new remote sensing detection method with high spatial and spectral information detection ability. In the process of laser scanning, the laser echo intensity is affected by many factors. Therefore, it is necessary to calibrate the backscatter intensity data of HSL. Laser incidence angle is one of the important factors that affect the backscatter intensity of the target. This paper studied the radiometric calibration method of incidence angle effect for HSL. The reflectance of natural surfaces can be simulated as a combination of specular reflection and diffuse reflection. The linear combination of the Lambertian model and Beckmann model provides a comprehensive theory that can be applied to various surface conditions, from glossy to rough surfaces. Therefore, an adaptive threshold radiometric calibration method (Lambertian-Beckmann model) is proposed to solve the problem caused by the incident angle effect. The relationship between backscatter intensity and incident angle of HSL is studied by combining theory with experiments, and the model successfully quantifies the difference between diffuse and specular reflectance coefficients. Compared with the Lambertian model, the proposed model has higher calibration accuracy, and the average improvement rate to the samples in this study was 22.67%. Compared with the results before calibration with the incidence angle of less than 70°, the average improvement rate of the Lambertian-Beckmann model was 62.26%. Moreover, we also found that the green leaves have an obvious specular reflection effect near 650-720 nm, which might be related to the inner microstructure of chlorophyll. The Lambertian-Beckmann model was more helpful to the calibration of leaves in the visible wavelength range. This is a meaningful and a breakthrough exploration for HSL.

18.
J Viral Hepat ; 27(11): 1096-1107, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32510704

RESUMO

Chronic hepatitis B virus (CHBV) infection is a major cause of liver diseases. Mucosal-associated invariant T (MAIT) cells are important for antiviral immunity in the liver, but the distinction between intrasinusoidal and peripheral MAIT cells in patients with CHBV infections remains unclear. PBMCs were obtained from patients with CHBV infections (n = 29) and age-matched controls (n = 46). Liver-associated mononuclear cells (LMCs) were collected from healthy donors (n = 29) and explanted livers (n = 19) from patients and used for phenotypic, functional and TCR diversity analyses. The percentages of both peripheral and intrasinusoidal MAIT cells were significantly reduced in the CHBV infection group compared to the control group. Peripheral MAIT cells from CHBV-infected patients expressed higher levels of HLA-DR, CD69, CD38 and PD-1 than those of controls. We also confirmed that peripheral MAIT cells in HBV patients had elevated expression T-cell exhaustion genes. Except for a difference in the level of PD-1, no differences were observed between the liver MAIT cells of the two groups. The production of IFN-α in peripheral MAIT cells of CHBV infection patients was lower than in control patients, but no such difference was observed in liver MAIT cells. Additionally, a distinct TCR signature was found in CHBV patients. Hence, we found distinct activities and functions in liver and peripheral MAIT cells of patients with CHBV infections.


Assuntos
Hepatite B Crônica , Células T Invariantes Associadas à Mucosa , Antivirais/uso terapêutico , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Humanos
19.
BMC Pregnancy Childbirth ; 20(1): 715, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33228631

RESUMO

BACKGROUND: Few studies have focused on cesarean delivery (CD) trends among primipara under the one-child and the two-child policies. This study aimed to explore the trends in CD rates among primipara during 1995-2019 and the associated factors with CD risk. METHODS: This study obtained clinical data on primiparous mothers and newborns from 1995 to 2019 at a large tertiary hospital in Wuhan, China. Trends in CD rates were calculated using the joinpoint regression analysis. The Chi-square tests and log-binomial regression analyses were used to evaluate the associations between primary variables and CD risk. RESULTS: CD rates showed a significant upward trend with an average annual percentage change (APC) of 2.2% (95% CI: 0.6, 3.8%) during the study period. In 1995-2006, the CD rates continued to increase with an APC of 7.8% (95% CI: 4.8, 10.9%). After 2006, the CD rates started to decline by an APC of - 4.1% (95% CI: - 5.5, - 2.6%). The CD rates non-significantly increased from 36.2% in 2016 to 43.2% in 2019. Moreover, the highest CD rate during 2015-2019 was observed on August 30 (59.2%) and the lowest on September 1 (29.7%). Primipara of older age and those with >3pregnancies had higher risks of CD. Furthermore, primipara who gave birth to newborns with low birth weight and macrosomia had higher risks of CD. CONCLUSIONS: Maternal and fetal as well as social and cultural factors may contribute to the rising trend of CD rates. Effective measures should be taken to control CD under the two-child policy, especially for primipara.


Assuntos
Cesárea/tendências , Peso Fetal , Idade Materna , Paridade , Adulto , Distribuição de Qui-Quadrado , China/epidemiologia , Política de Planejamento Familiar , Feminino , Macrossomia Fetal/epidemiologia , Humanos , Recém-Nascido , Masculino , Gravidez , Análise de Regressão , Fatores de Risco , Centros de Atenção Terciária , Adulto Jovem
20.
Sensors (Basel) ; 20(8)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316484

RESUMO

Estimating directions of arrival (DOA) without knowledge of the source number is regarded as a challenging task, particularly when coherence among sources exists. Researchers have trained deep learning (DL)-based models to attack the problem of DOA estimation. However, existing DL-based methods for coherent sources do not adapt to variable source numbers or require signal independence. Herein, we put forward a new framework combining parallel DOA estimators with Toeplitz matrix reconstruction to address the problem. Each estimator is constructed by connecting a multi-label classifier to a spatial filter, which is based on convolutional-recurrent neural networks. Spatial filters divide the angle domain into several sectors, so that the following classifiers can extract the arrival directions. Assisted with Toeplitz-based method for source-number determination, pseudo or missed angles classified by the estimators will be reduced. Then, the spatial spectrum can be more accurately recovered. In addition, the proposed method is data-driven, so it is naturally immune to signal coherence. Simulation results demonstrate the predominance of the proposed method and show that the trained model is robust to imperfect circumstances such as limited snapshots, colored Gaussian noise, and array imperfections.

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