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1.
Artículo en Inglés | MEDLINE | ID: mdl-38857454

RESUMEN

OBJECTIVES: Precise literature recommendation and summarization are crucial for biomedical professionals. While the latest iteration of generative pretrained transformer (GPT) incorporates 2 distinct modes-real-time search and pretrained model utilization-it encounters challenges in dealing with these tasks. Specifically, the real-time search can pinpoint some relevant articles but occasionally provides fabricated papers, whereas the pretrained model excels in generating well-structured summaries but struggles to cite specific sources. In response, this study introduces RefAI, an innovative retrieval-augmented generative tool designed to synergize the strengths of large language models (LLMs) while overcoming their limitations. MATERIALS AND METHODS: RefAI utilized PubMed for systematic literature retrieval, employed a novel multivariable algorithm for article recommendation, and leveraged GPT-4 turbo for summarization. Ten queries under 2 prevalent topics ("cancer immunotherapy and target therapy" and "LLMs in medicine") were chosen as use cases and 3 established counterparts (ChatGPT-4, ScholarAI, and Gemini) as our baselines. The evaluation was conducted by 10 domain experts through standard statistical analyses for performance comparison. RESULTS: The overall performance of RefAI surpassed that of the baselines across 5 evaluated dimensions-relevance and quality for literature recommendation, accuracy, comprehensiveness, and reference integration for summarization, with the majority exhibiting statistically significant improvements (P-values <.05). DISCUSSION: RefAI demonstrated substantial improvements in literature recommendation and summarization over existing tools, addressing issues like fabricated papers, metadata inaccuracies, restricted recommendations, and poor reference integration. CONCLUSION: By augmenting LLM with external resources and a novel ranking algorithm, RefAI is uniquely capable of recommending high-quality literature and generating well-structured summaries, holding the potential to meet the critical needs of biomedical professionals in navigating and synthesizing vast amounts of scientific literature.

2.
Gastroenterology ; 167(2): 298-314, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38467382

RESUMEN

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) has a desmoplastic tumor stroma and immunosuppressive microenvironment. Galectin-3 (GAL3) is enriched in PDAC, highly expressed by cancer cells and myeloid cells. However, the functional roles of GAL3 in the PDAC microenvironment remain elusive. METHODS: We generated a novel transgenic mouse model (LSL-KrasG12D/+;Trp53loxP/loxP;Pdx1-Cre;Lgals3-/- [KPPC;Lgals3-/-]) that allows the genetic depletion of GAL3 from both cancer cells and myeloid cells in spontaneous PDAC formation. Single-cell RNA-sequencing analysis was used to identify the alterations in the tumor microenvironment upon GAL3 depletion. We investigated both the cancer cell-intrinsic function and immunosuppressive function of GAL3. We also evaluated the therapeutic efficacy of GAL3 inhibition in combination with immunotherapy. RESULTS: Genetic deletion of GAL3 significantly inhibited the spontaneous pancreatic tumor progression and prolonged the survival of KPPC;Lgals3-/- mice. Single-cell analysis revealed that genetic deletion of GAL3 altered the phenotypes of immune cells, cancer cells, and other cell populations. GAL3 deletion significantly enriched the antitumor myeloid cell subpopulation with high major histocompatibility complex class II expression. We also identified that GAL3 depletion resulted in CXCL12 upregulation, which could act as a potential compensating mechanism on GAL3 deficiency. Combined inhibition of the CXCL12-CXCR4 axis and GAL3 enhanced the efficacy of anti-PD-1 immunotherapy, leading to significantly inhibited PDAC progression. In addition, deletion of GAL3 also inhibited the basal/mesenchymal-like phenotype of pancreatic cancer cells. CONCLUSIONS: GAL3 promotes PDAC progression and immunosuppression via both cancer cell-intrinsic and immune-related mechanisms. Combined treatment targeting GAL3, CXCL12-CXCR4 axis, and PD-1 represents a novel therapeutic strategy for PDAC.


Asunto(s)
Carcinoma Ductal Pancreático , Progresión de la Enfermedad , Galectina 3 , Neoplasias Pancreáticas , Microambiente Tumoral , Animales , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/terapia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/inmunología , Carcinoma Ductal Pancreático/terapia , Galectina 3/genética , Galectina 3/metabolismo , Galectina 3/antagonistas & inhibidores , Microambiente Tumoral/inmunología , Ratones , Humanos , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Modelos Animales de Enfermedad , Línea Celular Tumoral , Eliminación de Gen , Ratones Transgénicos , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/metabolismo , Receptor de Muerte Celular Programada 1/genética , Ratones Noqueados , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunoterapia/métodos , Transducción de Señal , Galectinas/genética , Galectinas/metabolismo
3.
J Mol Med (Berl) ; 102(2): 213-229, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38047923

RESUMEN

Cancer is a life-threatening disease worldwide. Nanomedicine and nanodelivery systems are recently developed scientific field that employs specific materials in the nanoscale range to deliver drugs. Lipid-based nanoparticles are an ideal delivery system since they exhibit many advantages, including high bioavailability, self-assembly, formulation simplicity, and the ability to exhibit a plethora of physicochemical properties. Herein, we report that phenobarbital sodium can kill cancer cells by using the DSPE-PEG2000-methotrexate nanoparticle delivery system, which can target folate receptors that are usually overexpressed on a variety of cancer cells. The released phenobarbital then executes cancer cells by inducing pyroptosis. Results from our animal model further indicate that the nanomedicine of nanoparticle-encapsulated phenobarbital sodium is a promising anticancer therapy.


Asunto(s)
Nanopartículas , Neoplasias , Fosfatidiletanolaminas , Polietilenglicoles , Animales , Metotrexato/farmacología , Sistemas de Liberación de Medicamentos/métodos , Piroptosis , Nanopartículas/química
4.
Cells ; 12(22)2023 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-37998349

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is a devastating malignant disease with a dismal prognosis. In the past decades, a plethora of genetically engineered mouse models (GEMMs) with autochthonous pancreatic tumor development have greatly facilitated studies of pancreatic cancer. Commonly used GEMMs of PDAC often harbor the oncogenic KRAS driver mutation (KrasG12D), in combination with either p53 mutation by knock-in strategy (Trp53R172H) or p53 loss by conditional knockout (Trp53cKO) strategy, in pancreatic cell lineages. However, the systematic comparison of the tumor microenvironment between KrasG12D; Trp53R172H (KPmut) mouse models and KrasG12D; Trp53cKO (KPloss) mouse models is still lacking. In this study, we conducted cross-dataset single-cell RNA-sequencing (scRNA-seq) analyses to compare the pancreatic tumor microenvironment from KPmut mouse models and KPloss mouse models, especially focusing on the cell compositions and transcriptomic phenotypes of major cell types including cancer cells, B cells, T cells, granulocytes, myeloid cells, cancer-associated fibroblasts, and endothelial cells. We identified the similarities and differences between KPmut and KPloss mouse models, revealing the effects of p53 mutation and p53 loss on oncogenic KRAS-driven pancreatic tumor progression.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animales , Ratones , Carcinoma Ductal Pancreático/metabolismo , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Mutación/genética , Neoplasias Pancreáticas/patología , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Análisis de la Célula Individual , Microambiente Tumoral , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
5.
Cancers (Basel) ; 15(8)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37190324

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) has a unique tumor microenvironment composed of various cell populations such as cancer cells, cancer-associated fibroblasts (CAFs), immune cells, and endothelial cells. Recently, single-cell RNA-sequencing analysis (scRNA-seq) has systemically revealed the genomic profiles of these cell populations in PDAC. However, the direct comparison of cell population composition and genomic profile between primary tumors (at both early- and late-stage) and metastatic tumors of PDAC is still lacking. In this study, we combined and analyzed recent scRNA-seq datasets of transgenic KPC mouse models with autochthonous PDAC and matched liver metastasis, revealing the unique tumor ecosystem and cell composition of liver metastasis in contrast to primary PDAC. Metastatic PDAC tumors harbor distinct cancer cell subpopulations from primary tumors. Several unique markers, including HMGA1, were identified for metastasis-enriched cancer cell subpopulations. Furthermore, metastatic tumors reveal significantly enriched granulocytic myeloid-derived suppressor cells (G-MDSCs), mature neutrophils, and granulocyte-myeloid progenitors (GMPs). A common GMP population across primary tumors, liver metastases, and healthy bone marrow was identified as the putative cell origin of tumor-associated neutrophils/granulocytes.

6.
Curr Issues Mol Biol ; 44(3): 1115-1126, 2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35723296

RESUMEN

Preclinical studies of COVID-19 mRNA vaccine BNT162b2, developed by Pfizer and BioNTech, showed reversible hepatic effects in animals that received the BNT162b2 injection. Furthermore, a recent study showed that SARS-CoV-2 RNA can be reverse-transcribed and integrated into the genome of human cells. In this study, we investigated the effect of BNT162b2 on the human liver cell line Huh7 in vitro. Huh7 cells were exposed to BNT162b2, and quantitative PCR was performed on RNA extracted from the cells. We detected high levels of BNT162b2 in Huh7 cells and changes in gene expression of long interspersed nuclear element-1 (LINE-1), which is an endogenous reverse transcriptase. Immunohistochemistry using antibody binding to LINE-1 open reading frame-1 RNA-binding protein (ORFp1) on Huh7 cells treated with BNT162b2 indicated increased nucleus distribution of LINE-1. PCR on genomic DNA of Huh7 cells exposed to BNT162b2 amplified the DNA sequence unique to BNT162b2. Our results indicate a fast up-take of BNT162b2 into human liver cell line Huh7, leading to changes in LINE-1 expression and distribution. We also show that BNT162b2 mRNA is reverse transcribed intracellularly into DNA in as fast as 6 h upon BNT162b2 exposure.

7.
Pest Manag Sci ; 78(6): 2523-2533, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35318801

RESUMEN

BACKGROUND: The European tarnished plant bug Lygus rugulipennis Poppius (Hemiptera: Miridae) can cause several types of damage to crops grown in greenhouses and fields, including flower abortion in eggplant, stem and fruit damage in cucumbers, and splits in chrysanthemums. Studies suggest that both male and female L. rugulipennis may be more attracted to traps based on visual attraction than pheromone-based trap. Therefore, the aim of this study was to evaluate the effectiveness of a water trap with LED lights and semiochemicals in trapping L. rugulipennis in the laboratory and greenhouse. RESULTS: The results showed that water traps equipped with white LED light caught 20 - 30 times more bugs than did the sex pheromone-based traps in greenhouse experiment. During the week of peak flight, the LED water trap caught a total of 29 males and females, whereas the sex pheromone caught only one male. Among the semiochemicals tested in a Y-tube, both males and females were attracted to ß-caryophyllene, but not in the presence of the sex pheromone, whereas both males and females were attracted to pentyl butyrate in the presence of the sex pheromone. The pheromone plus bean plant odor was attractive to the insects, suggesting an interaction between plant odor and pheromone. CONCLUSION: Overall, the findings of the study showed that the water trap with LED light could be an effective method for trapping L. rugulipennis in greenhouses. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Chrysanthemum , Hemípteros , Heterópteros , Atractivos Sexuales , Animales , Femenino , Masculino , Feromonas/farmacología , Atractivos Sexuales/farmacología , Agua/farmacología
8.
Cell Death Discov ; 8(1): 72, 2022 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-35184141

RESUMEN

Systemic inflammatory response syndrome (SIRS) is a sepsis-associated inflammatory state and a self-defense mechanism against specific and nonspecific stimuli. Ketamine influences many key processes that are altered during sepsis. However, the underlying mechanisms remain incompletely understood. In this study, TNF-α-treated mice, as well as HT-29 and L929 cell models, were applied to characterize TNF-α-induced systemic and local cecal tissue inflammatory responses. Behavioral, biochemical, histological, and molecular biological approaches were applied to illustrate the related processes. Mice with TNF-α-induced SIRS showed systemic and local cecal tissue inflammatory responses, as indicated by increased levels of high mobility group box 1 protein (HMGB1), chemokines (C-X-C motif) ligand 10 (CXCL10), interleukin-6 (IL-6), and IL-10, as well as high mortality. Ketamine pretreatment alleviated death rates, symptoms, and the production of inflammatory cytokines induced by TNF-α in mice. Moreover, ketamine also protected the mice from TNF-α-induced cecal damage by suppressing the phosphorylation of receptor-interacting serine/threonine-protein kinase 3 (RIP3) and mixed lineage kinase domain-like protein (MLKL). In addition, our results showed that ketamine efficiently inhibited TNF-α-induced necroptosis in HT-29 and L929 cells. Furthermore, we explored the mechanism using different L929 cell lines. The results displayed that ketamine inhibited TNF-α-induced necroptosis by enhancing RIP1 ubiquitination and reducing the RIP1-RIP3 and RIP3-MLKL interactions, as well as the formation of necrosomes. Thus, our study may provide a new theoretical and experimental basis for treating diseases characterized by SIRS-associated inflammatory factor storms. Moreover, our exploration may provide potential molecular mechanisms and targets for therapeutic intervention and clinical application of ketamine.

9.
J Cell Mol Med ; 26(2): 563-569, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34910369

RESUMEN

Aresenic trioxide (ATO) is proven to be active against leukaemia cells by inducing apoptosis and differentiation. Even though ATO could effectively induce remissions of leukaemia cells, the drug resistance was observed occasionally. To further dissect the mechanism of ATO resistance, we selected the ATO-resistant SH-SY5Y cells and found that Bcl-2 controlled the sensitivity of ATO in SH-SY5Y cells. We report that necroptosis, autophagy, NF-ƘB and MAPK signalling pathway are not involved in ATO-induced apoptosis. Moreover, the ATO-resistant cells showed distinct mitochondrial morphology compared with that of ATO-sensitive cells. Intriguingly, nude mice-bearing ATO-sensitive cells derived xenograft tumours are more sensitive to ATO treatment compared with that of ATO-resistant cells. These data demonstrate that cancer cells can acquire the ATO-resistance ability by increasing the Bcl-2 expression.


Asunto(s)
Antineoplásicos , Arsenicales , Animales , Antineoplásicos/farmacología , Apoptosis , Trióxido de Arsénico/farmacología , Arsenicales/farmacología , Línea Celular Tumoral , Humanos , Ratones , Ratones Desnudos , Óxidos/farmacología
10.
AME Case Rep ; 4: 25, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33178997

RESUMEN

Over the several years, only few cases of consciousness was diagnosed as pulmonary embolism in the world. The obstruction of the pulmonary arterial tree is viewed as the source of pulmonary embolism, and eventually trigger the severe cardiopulmonary failure. Diagnosis of pulmonary embolism is dependent on the imaging data, such as the computed tomographic detection. Above 50% of patients with pulmonary embolism are normotensive and they have neither echocardiographic nor laboratory signs of right heart dysfunction. Therefore, the precise prognosis of acute pulmonary embolism presented with rare characteristic is important to improve risk management. In some circumstance, the diagnosis of pulmonary embolism remains a challenge with atypical characterization presented in this case. A case report of this is given to accumulate the diagnostic experience for further analysis. Herein, we report a case of a severe pulmonary embolism that revealed by consciousness disorders. This report highlights the extracorporeal membrane oxygenation (ECMO) could be the only life-sustaining and the possibility of the solution treatment of acute pulmonary embolism.

11.
Int Immunopharmacol ; 85: 106664, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32521490

RESUMEN

Bacillus anthracis is a lethal agent of anthrax disease and the toxins are required in anthrax pathogenesis. The anthrax lethal toxin can trigger NLRP1b inflammasome activation and pyroptosis. Although the underlying mechanism is well understood, the medications targeting the NLRP1b inflammasome are not available in the clinic. Herein, we describe that BPTES, a known Glutaminase (GLS) inhibitor, is an effective NLRP1b inflammasome inhibitor. BPTES could effectively and specifically suppress NLRP1b inflammasome activation in macrophages but have no effects on NLRP3, NLRC4 and AIM2 inflammasome activation. Mechanistically, BPTES alleviated the UBR2 mediated proteasomal degradation pathway of the NLRP1b N terminus, thus blocking the release of the CARD domain for subsequent caspase-1 processing. Furthermore, BPTES could prevent disease progression in mice challenged with the anthrax lethal toxin. Taken together, our studies indicate that BPTES can be a promising pharmacological inhibitor to treat anthrax lethal toxin-related inflammatory diseases.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/antagonistas & inhibidores , Antiinflamatorios/uso terapéutico , Antígenos Bacterianos/toxicidad , Proteínas Reguladoras de la Apoptosis/antagonistas & inhibidores , Toxinas Bacterianas/toxicidad , Inflamasomas/antagonistas & inhibidores , Sulfuros/uso terapéutico , Tiadiazoles/uso terapéutico , Animales , Antiinflamatorios/farmacología , Línea Celular , Femenino , Humanos , Ratones Endogámicos BALB C , Sulfuros/farmacología , Tiadiazoles/farmacología
12.
Transl Cancer Res ; 9(3): 1926-1930, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35117539

RESUMEN

BACKGROUND: Arsenic trioxide (ATO) has been proved useful for the treatment of acute promyelocytic leukemia (APL). Apoptosis is the result of the cytotoxic effect of ATO, apoptotic mediated cell death confirmed by DNA fragmentation and Annexin V staining. Although signaling associated with ATO-induced apoptosis has been well defined, it is still unknown whether other forms of cell death are involved in ATO-induced cell death. METHODS: Western blotting, cytotoxicity assay, transmission electron microscopy were used to evaluate other forms of cell death in U251 cells. RESULTS: We found that pyroptotic mediated cell death was observed in U251 cells after ATO treatment, which was confirmed by observing the increased gasdermin E (GSDME) cleavage, lactate dehydrogenase (LDH) release and transmission electron microscopy imaging. Consistent with previous results, caspase-3 was activated by ATO, which was also important for GSDME cleavage and subsequent pyroptosis. CONCLUSIONS: We reported that GSDME mediated pyroptosis involved in ATO induced cell death in astroglioma cells.

13.
Cell Mol Immunol ; 17(4): 356-368, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31076724

RESUMEN

Interferons (IFNs) play an important role in immunomodulatory and antiviral functions. IFN-induced necroptosis has been reported in cells deficient in receptor-interacting protein kinase 1 (RIPK1), Fas-associated protein with death domain (FADD), or caspase-8, but the mechanism is largely unknown. Here, we report that the DNA-dependent activator of IFN regulatory factors (ZBP1, also known as DAI) is required for both type I (ß) and type II (γ) IFN-induced necroptosis. We show that L929 fibroblast cells became susceptible to IFN-induced necroptosis when RIPK1, FADD, or Caspase-8 was genetically deleted, confirming the antinecroptotic role of these proteins in IFN signaling. We found that the pronecroptotic signal from IFN stimulation depends on new protein synthesis and identified ZBP1, an IFN-stimulated gene (ISG) product, as the de novo synthesized protein that triggers necroptosis in IFN-stimulated cells. The N-terminal domain (ND) of ZBP1 is important for ZBP1-ZBP1 homointeraction, and its RHIM domain in the C-terminal region interacts with RIPK3 to initiate RIPK3-dependent necroptosis. The antinecroptotic function of RIPK1, FADD, and caspase-8 in IFN-treated cells is most likely executed by caspase-8-mediated cleavage of RIPK3, since the inhibitory effect on necroptosis was eliminated when the caspase-8 cleavage site in RIPK3 was mutated. ZBP1-mediated necroptosis in IFN-treated cells is likely physiologically relevant, as ZBP1 KO mice were significantly protected against acute systemic inflammatory response syndrome (SIRS) induced by TNF + IFN-γ.


Asunto(s)
Interferones/farmacología , Necroptosis , Proteínas de Unión al ARN/metabolismo , Animales , Caspasa 8/metabolismo , Línea Celular , Proteína de Dominio de Muerte Asociada a Fas/metabolismo , Humanos , Janus Quinasa 1/metabolismo , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Mutantes/metabolismo , Necroptosis/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Biosíntesis de Proteínas/efectos de los fármacos , Dominios Proteicos , Proteínas de Unión al ARN/química , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Factor de Transcripción STAT1/metabolismo , Transducción de Señal/efectos de los fármacos , Síndrome de Respuesta Inflamatoria Sistémica/metabolismo , Síndrome de Respuesta Inflamatoria Sistémica/patología , Factor de Necrosis Tumoral alfa
14.
Mol Cell Proteomics ; 18(6): 1054-1069, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30850422

RESUMEN

Lipopolysaccharide (LPS)-induced macrophage activation is a prototype of innate immune response. Although key effector proteins in LPS signaling pathway have been revealed, the map of dynamic protein interactions and phosphorylation as well as the stoichiometry of protein complexes are lacking. Here we present a dynamic map of protein interactions and phosphorylation in MyD88, TRAF6 and NEMO complexes obtained by SWATH-MS. The comprehensive MS measurement leads to quantification of up to about 3,000 proteins across about 21-40 IP samples. We detected and quantified almost all known interactors of MyD88, TRAF6 and NEMO. By analyzing these quantitative data, we uncovered differential recruitment of IRAK family proteins to LPS-induced signaling complexes and determined the stoichiometry of the Myddosome complex. In addition, quantitative phosphoproteomics analysis identified a number of unreported high-confidence phosphosites on the key proteins in LPS signaling pathway. Collectively, data of dynamic protein interactions and phosphorylation presented by this study could be a resource for further study of the LPS signaling pathway.


Asunto(s)
Lipopolisacáridos/metabolismo , Espectrometría de Masas/métodos , Transducción de Señal , Animales , Bases de Datos de Proteínas , Células HEK293 , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ratones , Factor 88 de Diferenciación Mieloide/metabolismo , Fosforilación , Unión Proteica , Células RAW 264.7 , Factor 6 Asociado a Receptor de TNF , Receptor Toll-Like 4/metabolismo
15.
Ecology ; 97(6): 1388-99, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27459770

RESUMEN

Interactions between predator and prey, or parasitoid and host, are shaped by trait- and density-mediated processes involving other community members. Parasitoids that lay their eggs in herbivorous insects locate their hosts through infochemicals such as herbivore-induced plant volatiles (HIPVs) and host-produced kairomones. Hosts are frequently accompanied by non-host herbivores that are unsuitable for the parasitoid. These non-hosts may interfere with host location primarily through trait-mediated processes, by their own infochemicals, and their induction of the emission of plant volatiles. Although it is known that single non-hosts can interfere with parasitoid host location, it is still unknown whether the observed effects are due to species specific characteristics or to the feeding habits of the non-host herbivores. Here we addressed whether the feeding guild of non-host herbivores differentially affects foraging of the parasitoid Cotesia glomerata for its common host, caterpillars of Pieris brassicae feeding on Brassica oleracea plants. We used different phloem-feeding and leaf-chewing non-hosts to study their effects on host location by the parasitoid when searching for host-infested plants based on HIPVs and when searching for hosts on the plant using infochemicals. To evaluate the ultimate effect of these two phases in host location, we studied parasitism efficiency of parasitoids in small plant communities under field-tent conditions. We show that leaf-chewing non-hosts primarily affected host location through trait-mediated effects via plant volatiles, whereas phloem-feeding non-hosts exerted trait-mediated effects by affecting foraging efficiency of the parasitoid on the plant. These trait-mediated effects resulted in associational susceptibility of hosts in environments with phloem feeders and associational resistance in environments with non-host leaf chewers.


Asunto(s)
Mariposas Nocturnas/parasitología , Avispas/fisiología , Animales , Conducta Animal , Interacciones Huésped-Parásitos , Larva/parasitología
16.
Proteomics ; 14(6): 713-24, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24453211

RESUMEN

Tumor necrosis factor (TNF) induced cell death in murine fibrosarcoma L929 cells is a model system in studying programed necrosis (also known as necroptosis). Receptor interacting protein 3 (RIP3), a serine-threonine kinase, is known to play an essential role in TNF-induced necroptosis; however, the phosphorylation events initiated by RIP3 activation in necroptotic process is still largely unknown. Here, we performed a quantitative MS based analysis to compare TNF-induced changes in the global phosphoproteome of wild-type (RIP3(+/+) ) and RIP3-knockdown L929 cells at different time points after TNF treatment. A total of 8058 phosphopeptides spanning 6892 phosphorylation sites in 2762 proteins were identified in the three experiments, in which cells were treated with TNF for 0.5, 2, and 4 h. By comparing the phosphorylation sites in wild-type and RIP3-knockdown L929 cells, 174, 167, and 177 distinct phosphorylation sites were revealed to be dependent on RIP3 at the 0.5, 2, and 4 h time points after TNF treatment, respectively. Notably, most of them were not detected in a previous phosphoproteomic analysis of RIP3-dependent phosphorylation in lipopolysaccharide-stimulated peritoneal macrophages and TNF-treated murine embryonic fibroblasts (MEFs), suggesting that the data presented in this report are highly relevant to the study of TNF-induced necroptosis of L929 cells.


Asunto(s)
Necrosis , Fosfopéptidos/análisis , Fosfoproteínas/análisis , Proteoma/análisis , Proteína Serina-Treonina Quinasas de Interacción con Receptores/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Secuencia de Aminoácidos , Animales , Línea Celular Tumoral , Técnicas de Silenciamiento del Gen , Lipopolisacáridos/inmunología , Macrófagos/citología , Macrófagos/inmunología , Espectrometría de Masas , Ratones , Fosfopéptidos/inmunología , Fosfoproteínas/inmunología , Fosforilación , Proteoma/inmunología , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética
17.
Zhonghua Liu Xing Bing Xue Za Zhi ; 33(1): 62-6, 2012 Jan.
Artículo en Chino | MEDLINE | ID: mdl-22575113

RESUMEN

OBJECTIVE: To study the epidemiological characteristics on the clustering nature of pandemic (H1N1) 2009 in China. METHODS: Time and place distribution of pandemic (H1N1) 2009 on the nature of clustering through data from Public Health Emergency Management Information System were described. RESULTS: As of August 10, 2010, 2773 pandemic (H1N1) 2009 clusters, a total of 77 363 cases (including 20 deaths) were reported in the mainland of China. The most reported number of clusters was from schools and kindergartens with the total number of 2498 (accounted for 90.08% of the total number). Middle schools appeared the have the most clusters (1223, accounting for 48.96%). The number of clusters reported in the southern provinces (cities) accounted for 77.03% of the total, and was more than that in the northern provinces (cities). Two reported peaks in the southern provinces (cities) were in June and November, 2009, respectively. There was only one reported peak in the northern provinces in September, 2009. CONCLUSION: Time and place distribution characteristics on the clusters of pandemic (H1N1) 2009 were similar to the seasonal influenza, but the beginning of winter peak was much earlier and intensity of reporting was much higher on the clusters of pandemic (H1N1) 2009 than that of seasonal influenza.


Asunto(s)
Brotes de Enfermedades , Subtipo H1N1 del Virus de la Influenza A , Gripe Humana/epidemiología , China/epidemiología , Análisis por Conglomerados , Humanos
18.
Zhonghua Liu Xing Bing Xue Za Zhi ; 28(2): 127-30, 2007 Feb.
Artículo en Chino | MEDLINE | ID: mdl-17649680

RESUMEN

OBJECTIVE: To identify the epidemical characteristics of suicidal tendency among middle-school students in cities of China and to explore the main factors leading to suicidal tendency in adolescents. METHODS: Multi-stage cluster sampling method was used to select 9015 students in grades 1, 2, 3 and 4 respectively from 25 general middle schools in Beijing, Hangzhou, Wuhan and Urumqi of China in June 2006 and field investigation was carried out through "China Global School-based Student Health Survey (GSHS) Questionnaire". RESULTS: Among the students in the four cities, the incidence rates of suicidal ideation were from 14.4% to 20.8% with an average of 17.4%. The incidence rates of suicidal plan were from 6.8% to 9.7% with an average of 8.2% and were different among cities. 15.0% of the boys had suicidal ideation and 6.7% of them made a suicidal plan comparing to 19.7% of girls having had suicidal ideation and 9.5% of them made a suicidal plan. The two kinds of suicidal tendency in girls were all higher than those in boys. City, age, gender, grade, days and type of being bullied, depression, close friends and having received health education on coping with stresses were factors influencing suicidal tendency of students. Days of being bullied and suicidal tendency showed a dose-response relation. CONCLUSION: Suicidal tendency seemed common in middle-school students. Training on 'coping the issue' should be strengthened and harmonious environment should be improved in middle-schools.


Asunto(s)
Estudiantes/psicología , Suicidio/estadística & datos numéricos , Adolescente , China/epidemiología , Recolección de Datos , Femenino , Humanos , Incidencia , Masculino , Suicidio/psicología , Población Urbana
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