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1.
Mol Phylogenet Evol ; 189: 107924, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37699449

RESUMO

Psyllids (class Insecta: order Hemiptera: superfamily Psylloidea) are a taxonomically and phylogenetically challenging clade. Recent studies have largely advanced the phylogeny of this group, yet the family-level relationships among Aphalaridae, Carsidaridae, and others remain unresolved. Genome-scale phylogenetic analysis is known to provide a finer resolution for problems like that. However, such phylogenomics also introduces new problems: incorrect trees with high confidence yielded due to systematic error (bias). Here we addressed these issues using hundreds of single-copy orthologous (SCO) genes in psyllid transcriptomes and genomes. Our analyses revealed conflicts between the nucleotide-based and amino-acid-based phylogenetic trees. While the nucleotide-based phylogeny strongly supported the (Aphalaridae + Carsidaridae) + Others relationship, the amino-acid-based one recovered Aphalaridae + (Carsidaridae + Others) with 100% support. Further inspection revealed significant compositional heterogeneity in nucleotide sequences for 67% of SCO genes, but not in the corresponding translated amino acid sequences. We then used different strategies to combat this compositional bias, and found that using the RY-coding strategy (coding the standard nucleotides as purines and pyrimidines) the nucleotide-based phylogeny became consistent with the amino-acid-based one. We further applied RY-coding to a published concatenated nucleotide dataset and recovered the Aphalaridae monophyly (which is refuted by the original literature on non-recoded sequences) at the base of psyllid tree. Moreover, it was found that variations in evolutionary rate could lead to errors in nucleotide-based phylogeny. The fast-evolving Heteropsylla cubana (Psyllidae: Ciriacreminae) was incorrectly placed within the subfamily Psyllinae. This bias can be avoided by using data removal or RY-coding strategies. Together, our results strongly support the family relationship of Aphalaridae + (Carsidaridae + Others), and show that the amino-acid-based concatenation analysis is more robust than nucleotide-based one. Future phylogenomic analysis of psyllid nucleotide sequences should take into account methods such as the RY-coding scheme to address potential systematic biases arising from composition and rate heterogeneities.


Assuntos
Hemípteros , Animais , Filogenia , Hemípteros/genética , Evolução Biológica , Nucleotídeos , Aminoácidos/genética , Viés
2.
BMC Cancer ; 23(1): 331, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041472

RESUMO

BACKGROUND: As a potential target receptor tyrosine kinase, mesenchymal-epithelial transition factor (MET) exhibits high aberrant expression across various tumors. This study aimed to evaluated the safety, tolerability, efficacy and pharmacokinetics (PK) of BPI-9016M, a novel tyrosine kinase inhibitor (TKI) targeting c-MET, in c-MET overexpression or MET exon 14 skipping mutation patients with locally advanced or metastatic non-small-cell lung cancer (NSCLC). METHODS/DESIGN: In this two-part multicenter phase Ib study, eligible patients with locally advanced or metastatic NSCLC harboring c-MET overexpression or MET exon 14 skipping mutation were enrolled into Part A (tested positive for c-MET overexpression [immunohistochemical staining score ≥ 2+]; 300 mg quaque die [QD], 450 mg QD and 600 mg QD cohorts) or Part B (tested positive for MET exon 14 skipping mutation; 400 mg bis in die [BID] cohort), respectively. The primary endpoints were safety, objective response rate (ORR) and disease control rate (DCR), the second endpoints were PK parameters, progression-free survival (PFS) and overall survival (OS). RESULTS: Between March 15, 2017 and September 18, 2021, 38 patients were enrolled (Part A, n = 34; Part B, n = 4). Of 38 patients, 32 (84.2%) patients completed the treatment protocol. As of the data cut-off date on January 27, 2022, all patients reported at least one treatment-emergent adverse event (TEAE). Ninety-two point one percent (35/38) of patients experienced treatment-related adverse events (TRAEs), and grade ≥ 3 TRAEs were observed in 11 (28.9%) patients. The most common TRAEs were elevated alanine aminotransferase (ALT, 14/38, 36.8%) and elevated aspartate aminotransferase (AST, 11/38, 28.9%). Only one (2.6%) patient had treatment-related serious adverse event (SAE) in 600 mg QD cohort due to thrombocytopenia. PK analysis showed BPI-9016M and its main metabolites (M1 and M2-2) reached steady state after seven days of continuous administration. At the dose of 300 mg QD and 450 mg QD, the exposure of BPI-9016M increased with increasing dose. Exposure of BPI-9016M was similar at 450 mg QD and 600 mg QD, which may exhibit a saturation trend. In all patients, ORR and DCR were 2.6% (1/38, 95% confidence interval [CI] 0.1-13.8%) and 42.1% (16/38, 95% CI 26.3-59.2%), respectively. Only one partial response (PR) patient was observed at a dose of 600 mg QD in Part A. In Part B, DCR was 75.0% (3/4, 95% CI 19.4-99.4%). The median PFS and OS in all 38 patients were 1.9 months (95% CI 1.9-3.7) and 10.3 months (95% CI 7.3-not evaluable [NE]), respectively. CONCLUSION: BPI-9016M showed manageable safety profile in c-MET overexpression or MET exon 14 skipping mutation patients with locally advanced or metastatic NSCLC, but showed limited efficacy. TRIAL REGISTRATION: Clinicaltrials.gov NCT02929290 (11/10/2016).


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Proteínas Proto-Oncogênicas c-met/genética , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Éxons
3.
Molecules ; 24(2)2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30669328

RESUMO

A lack of specificity is restricting the further application of conotoxin from Conus bullatus (BuIA). In this study, an analogue library of BuIA was established and virtual screening was used, which identified high α7 nicotinic acetylcholine receptor (nAChR)-selectivity analogues. The analogues were synthesized and tested for their affinity to functional human α7 nAChR and for the regulation of intracellular calcium ion capacity in neurons. Immunofluorescence, flow cytometry, and patch clamp results showed that the analogues maintained their capacity for calcium regulation. The results of the hot-plate model and paclitaxel-induced peripheral neuropathy model indicated that, when compared with natural BuIA, the analgesia activities of the analogues in different models were maintained. To analyze the adverse effects and toxicity of BuIA and its analogues, the tail suspension test, forced swimming test, and open field test were used. The results showed that the safety and toxicity of the analogues were significantly better than BuIA. The analogues of BuIA with an appropriate and rational mutation showed high selectivity and maintained the regulation of Ca2+ capacity in neurons and activities of analgesia, whereas the analogues demonstrated that the adverse effects of natural α-conotoxins could be reduced.


Assuntos
Analgésicos/química , Analgésicos/farmacologia , Conotoxinas/química , Conotoxinas/farmacologia , Desenho de Fármacos , Analgésicos/efeitos adversos , Cromatografia Líquida de Alta Pressão , Conotoxinas/efeitos adversos , Relação Dose-Resposta a Droga , Modelos Moleculares , Relação Estrutura-Atividade , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
4.
Chem Biodivers ; 14(6)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28281314

RESUMO

A new isoquinoline, 1,5-dihydroxy-4-methoxyisoquinoline (1), was obtained from Scolopendra subspinipes mutilans. Compound 1 showed moderate cytotoxicity on tumour cells with IC50 values ranging from 13 to 26 µm against five esophageal squamous cancer cells whereas low cytotoxicity against normal human esophageal epithelial cells. Isoquinoline ring oxidized at C(1), C(4), and C(5) can enhance its cytotoxicity. In addition, compound 1 showed potent inhibitory effect (inhibition rate > 50% at 13 µm) on cell migration in human umbilical vein endothelial cells. This article mainly studies the structure and activity of 1, and more modification of 1 as a potential anticancer agent.


Assuntos
Antineoplásicos/isolamento & purificação , Artrópodes/química , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Esofágicas/tratamento farmacológico , Isoquinolinas/farmacologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Carcinoma de Células Escamosas do Esôfago , Humanos , Concentração Inibidora 50 , Isoquinolinas/isolamento & purificação , Relação Estrutura-Atividade
5.
BMJ Open ; 14(6): e077108, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851227

RESUMO

OBJECTIVE: The aim of this study was to assess the clinical benefit value of approved antibody drug conjugates (ADCs) for solid tumours using the European Society for Medical Oncology Magnitude of Clinical Benefit Scale (ESMO-MCBS) V.1.1. DESIGN: Systematic descriptive analysis. DATA SOURCES: PubMed was searched for publications from 1 January 2000 to 18 October 2023. ELIGIBILITY CRITERIA: We included the phase III randomised controlled trials or phase II pivotal trials leading to approval of ADCs in solid tumours. DATA EXTRACTION AND SYNTHESIS: Two independent reviewers extracted data and discrepancies were resolved by consensus in the presence of a third investigator. RESULTS: ESMO-MCBS Scores were calculated for 16 positive clinical trials of eight ADCs, which were first approved by the US Food and Drug Administration (FDA), the European Medicines Agency (EMA), the China National Medical Products Administration and the Japanese Pharmaceuticals and Medical Devices Agency for solid cancers. Among 16 trials, 4 (25%) met the ESMO-MCBS benefit threshold grade, while 12 (75%) of the regimens did not meet the ESMO-MCBS benefit threshold grade. 5 (31%) of the 16 trials had no published scorecard on the ESMO website due to the approval by other jurisdictions but not by the FDA or EMA. Discrepancies between our results and the ESMO scorecard were observed in 4 (36%) of 11 trials, mostly owing to integration of more recent data. CONCLUSIONS: ESMO-MCBS is an important tool for assessing the clinical benefit of cancer drugs, but not all drugs met the meaningful benefit threshold.


Assuntos
Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Imunoconjugados , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Imunoconjugados/uso terapêutico , Antineoplásicos/uso terapêutico , Estados Unidos , Aprovação de Drogas
6.
Artigo em Inglês | MEDLINE | ID: mdl-38898784

RESUMO

AIM: To report the efficacy and safety of ensartinib, an anaplastic lymphoma kinase (ALK) inhibitor, in treating patients with ALK-positive advanced lung squamous cell carcinoma (LUSC) or lung adenosquamous carcinoma (LASC) in China. METHODS: This retrospective study analyzed data for 36 advanced-stage patients with ALK-positive LUSC (cohort A) and 13 patients with ALK-positive LASC (cohort B) between December 16, 2020 and December 16, 2021. All patients received once-daily ensartinib 225 mg. Outcome analysis included the demographic characteristics, tumor response, progression-free survival (PFS), and treatment-related adverse events (TRAE). RESULTS: Among the 49 patients, the majority were under 65 years old (73.5%), non-smokers (85.7%), had an Eastern Cooperative Oncology Group Performance Status of 0-1 (77.6%), and were at stage IV (71.4%). All patients were included in the efficacy and safety analysis. Seven PFS events were reported in cohort A while no patients experienced PFS events in cohort B. The median PFS was not estimable for both cohorts. In cohort A, the objective response rate (ORR) was 63.9%, and the disease control rate (DCR) was 83.3%. In the cohort B, the ORR was 76.9% and the DCR was 100.0%. Rash was the only TRAE reported in the cohort A (8.3%) and cohort B (23.1%). No patients had grade 3 or higher TRAE. CONCLUSION: Ensartinib has been tentatively proven favorable efficacy and tolerability in the treatment of patients with ALK-positive advanced LUSC or LASC in the real-world. However, confirmatory studies are still needed in larger sample sizes.

7.
Insects ; 14(11)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37999052

RESUMO

The aphid, Aphis gossypii Glover, is identified as a significant pest that causes severe damage to goji berries in China. To analyze the ladybird consumption of aphids, the functional responses of three ladybird species, Harmonia axyridis, Coccinella septempunctata, and Hippodamia variegata, and intraspecific competition among ladybird individuals were evaluated under laboratory conditions. Moreover, the practical impact of ladybirds on aphid population reduction was investigated in semi-field conditions. We found that all adult ladybirds of the three species exhibited a type II functional response toward aphids. According to Holling's disc equation, H. axyridis exhibited the highest searching efficiency (a = 0.79), while C. septempunctata had the shortest handling time (Th = 5.07 min) among the three ladybird species studied. Additionally, intraspecific competition had a greater impact on H. variegata (m = 0.41) compared to the other two ladybird species. The semi-field study demonstrated that H. axyridis (83.9% reduction) and C. septempunctata (78.7% reduction) exhibited higher efficacy in reducing aphid populations compared to H. variegata (27.3% reduction). This study suggests that H. axyridis and C. septempunctata exhibit potential as effective biological control agents against aphids on goji berry plants and highlights the importance of considering intraspecific competition. However, the results obtained from laboratory and semi-field studies cannot be directly extrapolated to field conditions due to the simplification of these experimental systems. Future field studies are crucial in ensuring the effective implementation of a biological control program.

8.
Insects ; 15(1)2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38249025

RESUMO

The psyllid Bactericera gobica is a serious pest in goji berry orchards. The current primary psyllid control methods involve chemical pesticides, which pose potential risks to human health and the environment. The implementation and promotion of biological control agents should receive increased attention as an alternative approach to safeguarding goji berry orchards. To compare the predatory performance of three potential biocontrol agents of psyllids, including Harmonia axyridis, Coccinella septempunctata and Hippodamia variegata, the functional response and intraspecific interactions of adult ladybirds were studied under laboratory conditions. We observed a significantly higher searching efficiency (0.84 ± 0.09) in H. axyridis when preying on psyllids compared to H. variegata (0.55 ± 0.05), whereas the handling time for psyllids was considerably longer in H. axyridis (7.33 ± 0.83 min) than in H. variegata (5.67 ± 0.97 min). The impact of intraspecific interactions on H. variegata (0.44 ± 0.04) was significantly greater than that on C. septempunctata (0.29 ± 0.03), whereas the maximum consumption by C. septempunctata (223.35 ± 41.3) significantly exceeded that of H. variegata (133.4 ± 26.9). Our study suggests that each of these three ladybird species possesses distinct advantages as a potential predator of psyllids. However, further field studies are required to determine the most promising ladybird species for rapid impact through inundative biological control, taking into consideration the specific environmental adaptability of each ladybird species. The present study is expected to provide evidence that supports the potential of incorporating promising ladybird species as an effective biological control agent in goji berry orchard management programs.

9.
Lung Cancer Manag ; 12(4): LMT61, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38239813

RESUMO

Aim: This retrospective study aimed to assess the efficacy and safety of ensartinib in Chinese patients with ALK-positive advanced NSCLC in real-world clinical practice. Methods: Clinical data from ALK-positive NSCLC patients treated with ensartinib in China were collected and analyzed. Efficacy end points included objective response rate and progression-free survival. Safety profiles were also evaluated. Results: A total of 682 patients were included in this study. The study demonstrated promising efficacy with an objective response rate of 54.0%, and the median progression-free survival was not estimable. Ensartinib exhibited a manageable safety profile with treatment-related adverse events (TRAEs) consistent with prior clinical trials. The most common TRAE was rash (21.1%) and no TRAE led to death. Conclusion: Ensartinib is active and well tolerated for ALK-positive NSCLC patients in real-world clinical settings.


Targeted therapies have significantly improved outcomes for patients with ALK-positive NSCLC. Ensartinib, a drug which blocks an enzyme in the body called ALK tyrosine kinase, has shown to be efficient and well tolerated in clinical trials. However, real-world evidence is crucial to confirm its effectiveness and safety in diverse patient populations. We analyzed the real-world outcomes of ensartinib treatment in 682 ALK-positive NSCLC patients in China, by looking at past records. The results showed that ensartinib demonstrated positive effects in most patients, meaning it helped in controlling their cancer progression. Side effects affected approximately one quarter of patients and most reported side effects were mild. Rash was the most reported side effect, accounting for about 21%. This study provides valuable insights into the real-world clinical performance of ensartinib, confirming its effectiveness and safety as a treatment option for ALK-positive NSCLC patients.

10.
Lancet Respir Med ; 11(10): 905-915, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37244266

RESUMO

BACKGROUND: Befotertinib (D-0316) is a novel, selective oral third-generation epidermal growth factor receptor (EGFR) tyrosine-kinase inhibitor. This phase 3 trial compared the efficacy and safety of befotertinib with icotinib as a first-line treatment for patients with EGFR mutation-positive locally advanced or metastatic non-small-cell lung cancer (NSCLC). METHODS: This study was a multicentre, open-label, randomised, controlled phase 3 study at 39 hospitals in China. Eligible patients were 18 years of age or older, had histologically confirmed locally advanced or metastatic stage IIIB, IIIC, or IV unresectable NSCLC, and had confirmed exon 19 deletions or exon 21 Leu858Arg mutation. Patients were randomly assigned (1:1) via an interactive web response system to receive either oral befotertinib (75-100 mg once daily) or oral icotinib (125 mg three times per day) in 21-day cycles until disease progression or withdrawal criteria were met. Randomisation was stratified by type of EGFR mutation, CNS metastasis status, and gender, and participants, investigators, and data analysts were not masked to treatment allocation. The primary endpoint was independent review committee (IRC)-assessed progression-free survival in the full analysis set, which comprised all randomly assigned patients. All patients who received at least one dose of the study drug were included in safety analyses. This study was registered with ClinicalTrials.gov, NCT04206072, and the overall survival follow-up is still in progress. FINDINGS: Between Dec 24, 2019, and Dec 18, 2020, 568 patients were screened, of whom 362 were randomly assigned to the befotertinib (n=182) or icotinib (n=180) group; all 362 patients were included in the full analysis set. Median follow-up was 20·7 months (IQR 10·2-23·5) in the befotertinib group and 19·4 months (10·3-23·5) in the icotinib group. Median IRC-assessed progression-free survival was 22·1 months (95% CI 17·9-not estimable) in the befotertinib group and 13·8 months (12·4-15·2) in the icotinib group (hazard ratio 0·49 [95% CI 0·36-0·68], p<0·0001). Grade 3 or higher treatment-related adverse events occurred in 55 (30%) of 182 patients in the befotertinib group and in 14 (8%) of 180 patients in the icotinib group. Treatment-related serious adverse events were reported in 37 (20%) patients in the befotertinib group and in five (3%) patients in the icotinib group. Two (1%) patients in the befotertinib group and one (1%) patient in the icotinib group died due to treatment-related adverse events. INTERPRETATION: Befotertinib demonstrated superior efficacy compared with icotinib in first-line treatment for patients with EGFR mutation-positive NSCLC. Although serious adverse events were more common in the befotertinib than the icotinib arm, the safety profile of befotertinib was manageable overall. FUNDING: Betta Pharmaceuticals (China). TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adolescente , Adulto , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Inibidores de Proteínas Quinases
11.
Pest Manag Sci ; 78(6): 2398-2404, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35277917

RESUMO

BACKGROUND: Insects living in unfavorably high or low temperatures are predicted to display a fast or slow life-history strategy. Here, we examined life histories of fall armyworm (FAW), a globally important invasive species with a broad ecological niche, at five constant temperatures of 13, 19, 25, 31 and 37°C, to study life-history responses to different temperatures. RESULTS: In our experiment, FAW had lower lifetime fecundity at unfavorable temperatures, a finding that is consistent with the idea that FAW can shift resources from reproduction to other functions under stressful conditions-such as heat or cold tolerance. Given the adverse effects of stressful temperatures, life-history strategies arise from individuals having limited remaining resources to allocate towards vital functions like survival or reproduction. Here we show plasticity in life-history strategies adopted at different temperatures. Rather than simply varying along a fast-slow continuum, FAW at unfavorably high temperatures exhibited lower daily fecundity and longer reproductive lifespans, and at unfavorably low temperatures showed a shorter peak in reproduction later in life, compared with FAW at 25°C. Such patterns, if adaptive, could suggest a strategy mitigating reproductive and mortality risk in unfavorable environments, however, this remains to be tested. CONCLUSION: Our analysis suggests that the high invasion success of FAW may result from their ability to adjust life-history strategies, across a range of stressful temperatures, in a way that reduces not only mortality, but also fecundity loss. The adoption of such strategies may be instrumental for the global invasion success of FAW. © 2022 Society of Chemical Industry.


Assuntos
Espécies Introduzidas , Características de História de Vida , Animais , Humanos , Spodoptera , Temperatura
12.
Insects ; 13(7)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35886753

RESUMO

The gall mite Aceria pallida and the psyllid Bactericera gobica are serious Goji berry pests. The mite can be phoretic on the psyllid to overwinter, but it is unclear whether the vector can obtain benefits from the phoront during the growing season. After detachment, the mite shares the same habitat with its vector, so there are very likely to be interspecific interactions. To better understand whether the interactions are positive or negative, information on relationships between abundances of A. pallida and B. gobica on leaves is needed. Here, B. gobica abundance was represented by the egg abundance because the inactive nymphs develop on the same sites after hatching. (1) We found a positive linear relationship between the gall diameter and the mite abundance in the gall (one more millimeter on gall diameter for every 30 mites increase), which provided a way to rapidly estimate mite abundances in the field by measuring gall diameters. (2) There was a positive relationship between the abundance of mites and psyllid eggs on leaves. (3) Both species had positive effects on each other's habitat selections. More importantly, the interactions of the two species prevented leaf abscission induced by B. gobica (leaf lifespan increased by 62.9%), increasing the continuation of the psyllid population. Our study suggests positive interactions between two pests during the growing season. The positive relationship between A. pallida and B. gobica egg abundances highlights the increasing need for novel methods for Goji berry pest management. In practice, A. pallida control can be efficient by eliminating its vector B. gobica. Both pests can be controlled together, which reduces chemical usage.

13.
Med Image Anal ; 68: 101901, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33285480

RESUMO

Temporal correlation in dynamic magnetic resonance imaging (MRI), such as cardiac MRI, is informative and important to understand motion mechanisms of body regions. Modeling such information into the MRI reconstruction process produces temporally coherent image sequence and reduces imaging artifacts and blurring. However, existing deep learning based approaches neglect motion information during the reconstruction procedure, while traditional motion-guided methods are hindered by heuristic parameter tuning and long inference time. We propose a novel dynamic MRI reconstruction approach called MODRN and an end-to-end improved version called MODRN(e2e), both of which enhance the reconstruction quality by infusing motion information into the modeling process with deep neural networks. The central idea is to decompose the motion-guided optimization problem of dynamic MRI reconstruction into three components: Dynamic Reconstruction Network, Motion Estimation and Motion Compensation. Extensive experiments have demonstrated the effectiveness of our proposed approach compared to other state-of-the-art approaches.


Assuntos
Imageamento por Ressonância Magnética , Redes Neurais de Computação , Algoritmos , Artefatos , Coração , Humanos , Processamento de Imagem Assistida por Computador , Movimento (Física)
14.
IEEE Trans Med Imaging ; 40(9): 2403-2414, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33945472

RESUMO

Instance segmentation is of great importance for many biological applications, such as study of neural cell interactions, plant phenotyping, and quantitatively measuring how cells react to drug treatment. In this paper, we propose a novel box-based instance segmentation method. Box-based instance segmentation methods capture objects via bounding boxes and then perform individual segmentation within each bounding box region. However, existing methods can hardly differentiate the target from its neighboring objects within the same bounding box region due to their similar textures and low-contrast boundaries. To deal with this problem, in this paper, we propose an object-guided instance segmentation method. Our method first detects the center points of the objects, from which the bounding box parameters are then predicted. To perform segmentation, an object-guided coarse-to-fine segmentation branch is built along with the detection branch. The segmentation branch reuses the object features as guidance to separate target object from the neighboring ones within the same bounding box region. To further improve the segmentation quality, we design an auxiliary feature refinement module that densely samples and refines point-wise features in the boundary regions. Experimental results on three biological image datasets demonstrate the advantages of our method. The code will be available at https://github.com/yijingru/ObjGuided-Instance-Segmentation.


Assuntos
Interpretação de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Redes Neurais de Computação
15.
Insects ; 11(11)2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182338

RESUMO

Tonic immobility (TI) is a well-known anti-predator strategy adopted by diverse preys. Numerous studies on the cost-benefit involve in TI have been reported. Although, some studies have reported the effect of mating behavior on TI, few studies highlight the phases of mate search. In the present study, we investigated the relationship between mate search and TI behavior in the sweetpotato weevil (SPW), Cylas formicarius (Coleoptera: Brentidae). First, we found the most active mate search period of male SPW within 24 h. Then, we measured whether the duration of TI of virgin male and female were affected during the mate search. In the end, the Y-tube olfactometer was used to compare the duration of mate search and the proportion of orientation towards the females in two artificial selection groups of the male SPW with longer and shorter duration of TI. Our study confirmed that male mate searching increase after 3 h at night, and up to 73% at midnight, TI was affected by mate search in male, because the duration of TI of the male during mate search (Mean ± SE = 214.53 ± 22.74 s) was significantly shorter duration than the control (679.64 ± 69.77 s). However, mate search did not affect the strength of TI in the females tested. This study determined that mate search was affected by TI due to males from the group with shorter duration of TI who had 28% higher proportion of orientation towards the females than the males with longer duration of TI. Investment trade-off between TI and mate search was confirmed in the males of the SPW.

16.
Insects ; 11(11)2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33207808

RESUMO

Functional responses of the fall armyworm (FAW) larvae at each stage, and their intraspecific competition associated with cannibalism, provide insights into developing pest management strategies for the FAW. To help use insecticides more sparingly, the functional response and intraspecific competition of the FAW larvae were evaluated under the laboratory conditions. The results showed that all stages of the FAW larvae displayed a type II functional response to diet. Based on Holling's disc equation, the search rate (a) and handling time (Th) of sixth instar larvae (a = 0.493; Th = 0.37 min) were the highest, and the shortest of all larval stages, respectively. Intraspecific competition curves fitted the data for fourth to sixth larval stages of the FAW, and the coefficient of intraspecific competition (m) assessed by the intraspecific competition equation were highest for fifth instar larvae (m = 0.48). The present study indicates that 5th and 6th instar larvae can cause the most plant damage (accounted for 88.9% of larval consumption), and these stages should be the focus of any pest management strategy. Intraspecific competition, especially cannibalism, impacts the feeding patterns of the FAW larvae and needs close attention. Understanding the functional response and intraspecific competition of the FAW larvae contributes greatly to practical applications of insecticides, increasing the effectiveness of chemical sprays and decreasing ecological damage.

17.
Insects ; 11(6)2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32575878

RESUMO

The fall armyworm, Spodoptera frugiperda (J.E. Smith) is a serious agricultural pest. The species originates from the tropical and subtropical regions of the Americas and has now become established in many countries. Its strong migratory ability is the key factor in the rapidly expanding range of S. frugiperda in Africa, where food security faces unprecedented challenges. Exploring potential distributions and niche differentiation of S. frugiperda could provide new insights into the nature of climate niche shifts and our ability to anticipate further invasions. In this study, the occurrence population records (native, source, global, and African) and environmental variables of S. frugiperda were selected to fit ecological niche models (ENMs), with an evaluation of niche conservatism during its invasion of Africa. The results showed that the potential distributions of S. frugiperda are mainly in tropical and subtropical areas in Africa. The climate spaces occupied by its native population and introduced African population broadly overlap. Although, climate niches were conserved during invasion of Africa, many climate spaces were unoccupied, suggesting a high remaining invasion potential in Africa. The selection of the biogeographic realm is an important factor in model construction, and has a great influence on the transferability of the models. Indeed, the global model produced the best performance, following the source and native models.

18.
Insect Sci ; 27(4): 815-825, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31250982

RESUMO

As solitary nymphal parasitoids of Paratrioza sinica, the ectoparasitoid Tamarixia lyciumi and the endoparasitoid Psyllaephagus arenarius act as effective biocontrol agents. Thus, it is necessary to facilitate mass productions of both species. Despite showing an excellent parasitic ability, Ps. arenarius is often trapped fatally inside 5th-instar nymphs of Pa. sinica due to strong host immunity. To improve the emergence rate of Ps. arenarius, we evaluated whether Ps. arenarius could utilize T. lyciumi venom via multiparasitism, so the parasitism characteristics of both species were examined between separate-existence (monoparasitism only) and co-existence (mono- and multiparasitism) systems. Further, the parasitism characteristics of Ps. arenarius on venom-injected hosts with/without T. lyciumi eggs were tested to further identify the facilitator. The results showed the parasitism rate of T. lyciumi was increased while that of Ps. arenarius did not change from separate-existence to co-existence systems. The intrinsic performances of two species in monoparasitism did not differ between separate- and co-existence systems. From monoparasitism (separate-existence) to multiparasitism (co-existence), no differences were detected in the intrinsic performances of T. lyciumi, but those of Ps. arenarius were greatly improved. After T. lyciumi venom injection, the parasitism characteristics of Ps. arenarius did not differ between venom-injected hosts with T. lyciumi eggs and those without, further indicating Ps. arenarius benefited from the venom of T. lyciumi females rather than T. lyciumi egg/larval secretions. Instead of negative effects, multiparasitism with ectoparasitoids improves endoparasitoids due to ectoparasitic venom. The study increases host resource utilization and provides creative ways for mass production of endoparasitoids.


Assuntos
Hemípteros/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Venenos de Vespas/metabolismo , Vespas/fisiologia , Animais , Feminino , Hemípteros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Ninfa/crescimento & desenvolvimento , Ninfa/parasitologia , Vespas/crescimento & desenvolvimento
19.
IEEE Trans Med Imaging ; 39(11): 3655-3666, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32746112

RESUMO

Nuclei segmentation is a fundamental task in histopathology image analysis. Typically, such segmentation tasks require significant effort to manually generate accurate pixel-wise annotations for fully supervised training. To alleviate such tedious and manual effort, in this paper we propose a novel weakly supervised segmentation framework based on partial points annotation, i.e., only a small portion of nuclei locations in each image are labeled. The framework consists of two learning stages. In the first stage, we design a semi-supervised strategy to learn a detection model from partially labeled nuclei locations. Specifically, an extended Gaussian mask is designed to train an initial model with partially labeled data. Then, self-training with background propagation is proposed to make use of the unlabeled regions to boost nuclei detection and suppress false positives. In the second stage, a segmentation model is trained from the detected nuclei locations in a weakly-supervised fashion. Two types of coarse labels with complementary information are derived from the detected points and are then utilized to train a deep neural network. The fully-connected conditional random field loss is utilized in training to further refine the model without introducing extra computational complexity during inference. The proposed method is extensively evaluated on two nuclei segmentation datasets. The experimental results demonstrate that our method can achieve competitive performance compared to the fully supervised counterpart and the state-of-the-art methods while requiring significantly less annotation effort.


Assuntos
Processamento de Imagem Assistida por Computador , Aprendizado de Máquina Supervisionado , Redes Neurais de Computação
20.
Pest Manag Sci ; 75(2): 484-491, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30022594

RESUMO

BACKGROUND: Since larval cannibalism is frequently observed in intensive rearing systems, the regeneration of lost legs is common for the beneficial species Coccinella septempunctata (Coccinella: Coccinellidae) to adapt to the competitive environment, but whether functional recovery occurs in the leg-regenerated coccinellids remains unknown. To evaluate the functional recovery of regenerated right foreleg after being damaged, the behaviors of leg-regenerated ladybugs containing predation, attachment, intraspecific competition, prey preference and fecundity were studied in the laboratory. RESULTS: The prey consumption and searching rate of leg-regenerated ladybugs decreased, and their handling time extended. A significantly reduced attachment coefficient was detected in leg-regenerated coccinellids. Because of the competitive inferiority, leg-regenerated ladybugs were greatly hampered in competition with normal opponents, and this inferiority led to a switch of prey preference from big-sized adults to small-sized first-second instar nymphs of Paratrioza sinica. However, although reduced functional abilities were examined, the leg-regenerated paternity had a higher reproductive output compared to the normal paternity. CONCLUSION: Leg-regenerated ladybugs caused by cannibalism may make an investment tradeoff between egg fecundity and functional recovery. Thus, larval cannibalism potentially improves the offspring production of the biological control agent in complex environments. © 2018 Society of Chemical Industry.


Assuntos
Besouros/fisiologia , Fertilidade , Comportamento Predatório , Animais , Canibalismo , Besouros/crescimento & desenvolvimento , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino
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