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  1 / 13998 MEDLINE  
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[PMID]:29190282
[Au] Autor:Ruiz F; Castelletto ML; Gang SS; Hallem EA
[Ad] Endereço:Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, California, United States of America.
[Ti] Título:Experience-dependent olfactory behaviors of the parasitic nematode Heligmosomoides polygyrus.
[So] Source:PLoS Pathog;13(11):e1006709, 2017 Nov.
[Is] ISSN:1553-7374
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Parasitic nematodes of humans and livestock cause extensive disease and economic loss worldwide. Many parasitic nematodes infect hosts as third-stage larvae, called iL3s. iL3s vary in their infection route: some infect by skin penetration, others by passive ingestion. Skin-penetrating iL3s actively search for hosts using host-emitted olfactory cues, but the extent to which passively ingested iL3s respond to olfactory cues was largely unknown. Here, we examined the olfactory behaviors of the passively ingested murine gastrointestinal parasite Heligmosomoides polygyrus. H. polygyrus iL3s were thought to reside primarily on mouse feces, and infect when mice consume feces containing iL3s. However, iL3s can also adhere to mouse fur and infect orally during grooming. Here, we show that H. polygyrus iL3s are highly active and show robust attraction to host feces. Despite their attraction to feces, many iL3s migrate off feces to engage in environmental navigation. In addition, H. polygyrus iL3s are attracted to mammalian skin odorants, suggesting that they migrate toward hosts. The olfactory preferences of H. polygyrus are flexible: some odorants are repulsive for iL3s maintained on feces but attractive for iL3s maintained off feces. Experience-dependent modulation of olfactory behavior occurs over the course of days and is mediated by environmental carbon dioxide (CO2) levels. Similar experience-dependent olfactory plasticity occurs in the passively ingested ruminant-parasitic nematode Haemonchus contortus, a major veterinary parasite. Our results suggest that passively ingested iL3s migrate off their original fecal source and actively navigate toward hosts or new host fecal sources using olfactory cues. Olfactory plasticity may be a mechanism that enables iL3s to switch from dispersal behavior to host-seeking behavior. Together, our results demonstrate that passively ingested nematodes do not remain inactive waiting to be swallowed, but rather display complex sensory-driven behaviors to position themselves for host ingestion. Disrupting these behaviors may be a new avenue for preventing infections.
[Mh] Termos MeSH primário: Haemonchus
Interações Hospedeiro-Parasita/imunologia
Enteropatias Parasitárias/parasitologia
Nematospiroides dubius
[Mh] Termos MeSH secundário: Animais
Quimiotaxia/imunologia
Interações Hospedeiro-Parasita/fisiologia
Larva/imunologia
Odorantes
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1712
[Cu] Atualização por classe:180302
[Lr] Data última revisão:
180302
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171201
[St] Status:MEDLINE
[do] DOI:10.1371/journal.ppat.1006709


  2 / 13998 MEDLINE  
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[PMID]:29351336
[Au] Autor:Pankratova EV; Kalyakulina AI; Krivonosov MI; Denisov SV; Taute KM; Zaburdaev VY
[Ad] Endereço:Institute of Information Technologies, Mathematics and Mechanics, Lobachevsky State University, Nizhniy Novgorod, Russia.
[Ti] Título:Chemotactic drift speed for bacterial motility pattern with two alternating turning events.
[So] Source:PLoS One;13(1):e0190434, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacterial chemotaxis is one of the most extensively studied adaptive responses in cells. Many bacteria are able to bias their apparently random motion to produce a drift in the direction of the increasing chemoattractant concentration. It has been recognized that the particular motility pattern employed by moving bacteria has a direct impact on the efficiency of chemotaxis. The linear theory of chemotaxis pioneered by de Gennes allows for calculation of the drift velocity in small gradients for bacteria with basic motility patterns. However, recent experimental data on several bacterial species highlighted the motility pattern where the almost straight runs of cells are interspersed with turning events leading to the reorientation of the cell swimming directions with two distinct angles following in strictly alternating order. In this manuscript we generalize the linear theory of chemotaxis to calculate the chemotactic drift speed for the motility pattern of bacteria with two turning angles. By using the experimental data on motility parameters of V. alginolyticus bacteria we can use our theory to relate the efficiency of chemotaxis and the size of bacterial cell body. The results of this work can have a straightforward extension to address most general motility patterns with alternating angles, speeds and durations of runs.
[Mh] Termos MeSH primário: Quimiotaxia/fisiologia
Modelos Biológicos
Vibrio alginolyticus/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180215
[Lr] Data última revisão:
180215
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180120
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0190434


  3 / 13998 MEDLINE  
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[PMID]:29258824
[Au] Autor:Bai W; Zhou J; Zhou N; Liu Q; Cui J; Zou W; Zhang W
[Ad] Endereço:Department of Respiratory Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, China.
[Ti] Título:Hypoxia-increased RAGE expression regulates chemotaxis and pro-inflammatory cytokines release through nuclear translocation of NF-κ B and HIF1α in THP-1 cells.
[So] Source:Biochem Biophys Res Commun;495(3):2282-2288, 2018 01 15.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The potential role of hypoxia in mediating the receptor for advanced glycation end products (RAGE) expression deserves to be confirmed. And the role of RAGE in hypoxia-induced chemotaxis and inflammation is still unclear. In present study, THP-1 cells were pretreated with siRNA to block HIF1α, NF-κ B, or RAGE, followed by exposed to hypoxia (combined with H O or SNP), and then RAGE expression, nuclear translocation of HIF1α and NF-κ B, release of TNF-α and IL-1ß, as well as expression of MCP-1 and CCR2 were measured. The results revealed that RAGE mRNA and protein in THP-1 cells were significantly increased after exposed into hypoxia atmosphere, especially into the solution containing SNP or H O . Moreover, SNP or H O exposure could further amplify hypoxia-induced nuclear translocation of HIF-1α and NF-κ B. Knockdown HIF-1α or NF-κ B by siRNAs could reduce hypoxia- and oxidative stress-induced RAGE hyper-expression. And pretreatment THP-1 cells with RAGE siRNA or NF-κ B siRNA could reduce hypoxia- and oxidative stress-induced expression of MCP-1 and CCR2, and release of TNF-α and IL-1ß. Thus, hypoxia not only increases RAGE expression in THP-1 cells by promoting nuclear translocation of NF-κ B and HIF1α, but also regulates chemotaxis and pro-inflammatory cytokines release, which may be partially mediated through upregulation of RAGE expression.
[Mh] Termos MeSH primário: Antígenos de Neoplasias/imunologia
Hipóxia Celular/imunologia
Núcleo Celular/imunologia
Quimiotaxia/imunologia
Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia
Mediadores da Inflamação/imunologia
Proteínas Quinases Ativadas por Mitógeno/imunologia
NF-kappa B/imunologia
[Mh] Termos MeSH secundário: Transporte Ativo do Núcleo Celular/imunologia
Seres Humanos
Células THP-1
Regulação para Cima/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Antigens, Neoplasm); 0 (HIF1A protein, human); 0 (Hypoxia-Inducible Factor 1, alpha Subunit); 0 (Inflammation Mediators); 0 (NF-kappa B); EC 2.7.11.22 (MOK protein, human); EC 2.7.11.24 (Mitogen-Activated Protein Kinases)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180214
[Lr] Data última revisão:
180214
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171221
[St] Status:MEDLINE


  4 / 13998 MEDLINE  
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[PMID]:28458362
[Au] Autor:Tanaka K; Yoshitomi T; Hirahara K
[Ad] Endereço:Biologics & Immuno-Oncology Laboratories, Daiichi Sankyo Co., Ltd.
[Ti] Título:Elucidation of Distinct Roles of Guinea Pig CXCR1 and CXCR2 in Neutrophil Migration toward IL-8 and GROα by Specific Antibodies.
[So] Source:Biol Pharm Bull;40(5):729-732, 2017.
[Is] ISSN:1347-5215
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Chemokine receptors CXCR1 and CXCR2 are conserved between guinea pigs and humans, but the distinct role of each receptor in chemotactic responses of neutrophils against chemokine ligands has not been elucidated due in part to the lack of specific inhibitors against these receptors in guinea pigs. In this study, we investigated the roles of guinea pig CXCR1 and CXCR2 on neutrophils in chemotactic responses to guinea pig interleukin (IL)-8 and growth-regulated oncogene (GRO)α by using specific inhibitory antibodies against these receptors. Neutrophil migration induced by IL-8 was partially inhibited by either anti-CXCR1 antibody or anti-CXCR2 antibody. In addition, the migration was inhibited completely when both anti-CXCR1 and anti-CXCR2 antibodies were combined. On the other hand, neutrophil migration induced by GROα was not inhibited by anti-CXCR1 antibody while inhibited profoundly by anti-CXCR2 antibody. These results indicated that CXCR1 and CXCR2 mediated migration induced by the IL-8 synergistically and only CXCR2 mediated migration induced by GROα in guinea pig neutrophils. Our findings on ligand selectivity of CXCR1 and CXCR2 in guinea pigs are consistent with those in humans.
[Mh] Termos MeSH primário: Quimiocina CXCL1/farmacologia
Interleucina-8/farmacologia
Neutrófilos/fisiologia
Receptores de Interleucina-8A/fisiologia
Receptores de Interleucina-8B/fisiologia
[Mh] Termos MeSH secundário: Animais
Anticorpos Bloqueadores/farmacologia
Movimento Celular/efeitos dos fármacos
Quimiocina CXCL1/antagonistas & inibidores
Quimiotaxia/efeitos dos fármacos
Feminino
Cobaias
Doenças do Sistema Imune
Interleucina-8/antagonistas & inibidores
Transtornos Leucocíticos
Neutrófilos/imunologia
Receptores de Interleucina-8A/imunologia
Receptores de Interleucina-8B/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Blocking); 0 (Chemokine CXCL1); 0 (Interleukin-8); 0 (Receptors, Interleukin-8A); 0 (Receptors, Interleukin-8B)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE
[do] DOI:10.1248/bpb.b16-00918


  5 / 13998 MEDLINE  
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[PMID]:29243668
[Au] Autor:Jin C; Hokmabad BV; Baldwin KA; Maass CC
[Ad] Endereço:Max Planck Institute for Dynamics and Self-Organization, Am Fassberg 17, 37077 Göttingen, Germany.
[Ti] Título:Chemotactic droplet swimmers in complex geometries.
[So] Source:J Phys Condens Matter;30(5):054003, 2018 Feb 07.
[Is] ISSN:1361-648X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Chemotaxis and auto-chemotaxis are key mechanisms in the dynamics of micro-organisms, e.g. in the acquisition of nutrients and in the communication between individuals, influencing the collective behaviour. However, chemical signalling and the natural environment of biological swimmers are generally complex, making them hard to access analytically. We present a well-controlled, tunable artificial model to study chemotaxis and autochemotaxis in complex geometries, using microfluidic assays of self-propelling oil droplets in an aqueous surfactant solution (Herminghaus et al 2014 Soft Matter 10 7008-22; Krüger et al 2016 Phys. Rev. Lett. 117). Droplets propel via interfacial Marangoni stresses powered by micellar solubilisation. Moreover, filled micelles act as a chemical repellent by diffusive phoretic gradient forces. We have studied these chemotactic effects in a series of microfluidic geometries, as published in Jin et al (2017 Proc. Natl Acad. Sci. 114 5089-94): first, droplets are guided along the shortest path through a maze by surfactant diffusing into the maze from the exit. Second, we let auto-chemotactic droplet swimmers pass through bifurcating microfluidic channels and record anticorrelations between the branch choices of consecutive droplets. We present an analytical Langevin model matching the experimental data. In a previously unpublished experiment, pillar arrays of variable sizes and shapes provide a convex wall interacting with the swimmer and, in the case of attachment, bending its trajectory and forcing it to revert to its own trail. We observe different behaviours based on the interplay of wall curvature and negative autochemotaxis, i.e. no attachment for highly curved interfaces, stable trapping at large pillars, and a narrow transition region where negative autochemotaxis makes the swimmers detach after a single orbit.
[Mh] Termos MeSH primário: Quimiotaxia
Tensoativos/química
[Mh] Termos MeSH secundário: Bactérias
Difusão
Microfluídica
Água/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Surface-Active Agents); 059QF0KO0R (Water)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180208
[Lr] Data última revisão:
180208
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171216
[St] Status:MEDLINE
[do] DOI:10.1088/1361-648X/aaa208


  6 / 13998 MEDLINE  
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[PMID]:29219578
[Au] Autor:Varennes J; Fancher S; Han B; Mugler A
[Ad] Endereço:Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA.
[Ti] Título:Emergent versus Individual-Based Multicellular Chemotaxis.
[So] Source:Phys Rev Lett;119(18):188101, 2017 Nov 03.
[Is] ISSN:1079-7114
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Multicellular chemotaxis can occur via individually chemotaxing cells that are mechanically coupled. Alternatively, it can emerge collectively, from cells chemotaxing differently in a group than they would individually. Here we consider collective movement that emerges from cells on the exterior of the collective responding to chemotactic signals, whereas bulk cells remain uninvolved in sensing and directing the collective. We find that the precision of this type of emergent chemotaxis is higher than that of individual-based chemotaxis for one-dimensional cell chains and two-dimensional cell sheets, but not three-dimensional cell clusters. We describe the physical origins of these results, discuss their biological implications, and show how they can be tested using common experimental measures such as the chemotactic index.
[Mh] Termos MeSH primário: Movimento Celular
Quimiotaxia
Modelos Biológicos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180207
[Lr] Data última revisão:
180207
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171209
[St] Status:MEDLINE
[do] DOI:10.1103/PhysRevLett.119.188101


  7 / 13998 MEDLINE  
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[PMID]:29194752
[Au] Autor:Engen SA; Schreurs O; Petersen F; Blix IJS; Baekkevold ES; Schenck K
[Ad] Endereço:Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.
[Ti] Título:The Regulatory Role of the Oral Commensal Streptococcus mitis on Human Monocytes.
[So] Source:Scand J Immunol;87(2):80-87, 2018 Feb.
[Is] ISSN:1365-3083
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Streptococcus mitis colonizes all niches of the human oral cavity from early infancy and throughout life. Monocytes patrol blood vessels, lymphoid and non-lymphoid tissues and migrate into infected tissue where they participate in the inflammatory cascade and immune regulation. Here, we studied the effect of S. mitis on monocytes. Transcriptome analysis of monocytes exposed to S. mitis (SmMo) revealed increased transcription of chemotactic factors (CCL2, CCL3, CCL20, CXCL1, CXCL2) and cytokines (IL1A, IL1B, IL6, IL23, IL36G, TNF), indicating that S. mitis may trigger recruitment of leucocytes and initiate inflammation. Increased transcription in SmMo of IL1B, IL6 and IL23 indicated that S. mitis may participate in the induction of Th17 responses and agreed with our earlier findings of S. mitis-mediated memory Th17 reactivity. Furthermore, S. mitis inhibited tetanus toxoid-specific CD4 T cell proliferation. This can be due to the increased secretion of IL-10 and expression of PD-L1 that was observed in SmMo. PGE2 can modulate IL-10 and PD-L1 expression, concomitant with that of CCR7, IL-12 and IL-23 that also were changed. This, along with increased SmMo transcription of PTGS2 (COX2) and PTGER4 (EP4), pointed to a role of PGE2. Measurement of PGE2 secretion by SmMo showed indeed a marked increase, and chemical inhibition of PGE2 production lowered the PD-L1 expression on SmMo. In conclusion, our findings show that S. mitis may trigger immune modulation by recruiting immune cells to the site of infection, while at the same time dampening the severity of the response through expression of IL-10, PGE2 and PD-L1.
[Mh] Termos MeSH primário: Monócitos/imunologia
Boca/microbiologia
Infecções Estreptocócicas/imunologia
Streptococcus mitis/imunologia
[Mh] Termos MeSH secundário: Antígeno B7-H1/metabolismo
Células Cultivadas
Quimiotaxia
Ciclo-Oxigenase 2/genética
Ciclo-Oxigenase 2/metabolismo
Citocinas/genética
Citocinas/metabolismo
Dinoprostona/metabolismo
Perfilação da Expressão Gênica
Regulação da Expressão Gênica
Seres Humanos
Imunomodulação
Mediadores da Inflamação/metabolismo
Monócitos/microbiologia
Receptores de Prostaglandina E Subtipo EP4/genética
Receptores de Prostaglandina E Subtipo EP4/metabolismo
Simbiose
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (B7-H1 Antigen); 0 (Cytokines); 0 (Inflammation Mediators); 0 (PTGER4 protein, human); 0 (Receptors, Prostaglandin E, EP4 Subtype); EC 1.14.99.1 (Cyclooxygenase 2); EC 1.14.99.1 (PTGS2 protein, human); K7Q1JQR04M (Dinoprostone)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180206
[Lr] Data última revisão:
180206
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171202
[St] Status:MEDLINE
[do] DOI:10.1111/sji.12636


  8 / 13998 MEDLINE  
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[PMID]:28465358
[Au] Autor:Amankulor NM; Kim Y; Arora S; Kargl J; Szulzewsky F; Hanke M; Margineantu DH; Rao A; Bolouri H; Delrow J; Hockenbery D; Houghton AM; Holland EC
[Ad] Endereço:Department of Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA.
[Ti] Título:Mutant IDH1 regulates the tumor-associated immune system in gliomas.
[So] Source:Genes Dev;31(8):774-786, 2017 04 15.
[Is] ISSN:1549-5477
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Gliomas harboring mutations in isocitrate dehydrogenase 1/2 (IDH1/2) have the CpG island methylator phenotype (CIMP) and significantly longer patient survival time than wild-type IDH1/2 (wtIDH1/2) tumors. Although there are many factors underlying the differences in survival between these two tumor types, immune-related differences in cell content are potentially important contributors. In order to investigate the role of IDH mutations in immune response, we created a syngeneic pair mouse model for mutant IDH1 (muIDH1) and wtIDH1 gliomas and demonstrated that muIDH1 mice showed many molecular and clinical similarities to muIDH1 human gliomas, including a 100-fold higher concentration of 2-hydroxygluratate (2-HG), longer survival time, and higher CpG methylation compared with wtIDH1. Also, we showed that IDH1 mutations caused down-regulation of leukocyte chemotaxis, resulting in repression of the tumor-associated immune system. Given that significant infiltration of immune cells such as macrophages, microglia, monocytes, and neutrophils is linked to poor prognosis in many cancer types, these reduced immune infiltrates in muIDH1 glioma tumors may contribute in part to the differences in aggressiveness of the two glioma types.
[Mh] Termos MeSH primário: Neoplasias Encefálicas/genética
Neoplasias Encefálicas/imunologia
Glioma/genética
Glioma/imunologia
Sistema Imunitário/fisiopatologia
Isocitrato Desidrogenase/genética
Isocitrato Desidrogenase/metabolismo
[Mh] Termos MeSH secundário: Animais
Neoplasias Encefálicas/enzimologia
Quimiotaxia/genética
Metilação de DNA
Modelos Animais de Doenças
Glioma/enzimologia
Seres Humanos
Antígenos Comuns de Leucócito/metabolismo
Leucócitos/patologia
Camundongos
Mutação
Infiltração de Neutrófilos/genética
Neutrófilos/patologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
EC 1.1.1.41 (Isocitrate Dehydrogenase); EC 3.1.3.48 (Leukocyte Common Antigens)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:180130
[Lr] Data última revisão:
180130
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1101/gad.294991.116


  9 / 13998 MEDLINE  
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[PMID]:28745641
[Au] Autor:Chai CM; Cronin CJ; Sternberg PW
[Ad] Endereço:Division of Biology and Bioengineering, California Institute of Technology; Howard Hughes Medical Institute, California Institute of Technology; cchai@caltech.edu.
[Ti] Título:Automated Analysis of a Nematode Population-based Chemosensory Preference Assay.
[So] Source:J Vis Exp;(125), 2017 Jul 13.
[Is] ISSN:1940-087X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The nematode, Caenorhabditis elegans' compact nervous system of only 302 neurons underlies a diverse repertoire of behaviors. To facilitate the dissection of the neural circuits underlying these behaviors, the development of robust and reproducible behavioral assays is necessary. Previous C. elegans behavioral studies have used variations of a "drop test", a "chemotaxis assay", and a "retention assay" to investigate the response of C. elegans to soluble compounds. The method described in this article seeks to combine the complementary strengths of the three aforementioned assays. Briefly, a small circle in the middle of each assay plate is divided into four quadrants with the control and experimental solutions alternately placed. After the addition of the worms, the assay plates are loaded into a behavior chamber where microscope cameras record the worms' encounters with the treated regions. Automated video analysis is then performed and a preference index (PI) value for each video is generated. The video acquisition and automated analysis features of this method minimizes the experimenter's involvement and any associated errors. Furthermore, minute amounts of the experimental compound are used per assay and the behavior chamber's multi-camera setup increases experimental throughput. This method is particularly useful for conducting behavioral screens of genetic mutants and novel chemical compounds. However, this method is not appropriate for studying stimulus gradient navigation due to the close proximity of the control and experimental solution regions. It should also not be used when only a small population of worms is available. While suitable for assaying responses only to soluble compounds in its current form, this method can be easily modified to accommodate multimodal sensory interaction and optogenetic studies. This method can also be adapted to assay the chemosensory responses of other nematode species.
[Mh] Termos MeSH primário: Bioensaio
Caenorhabditis elegans/fisiologia
[Mh] Termos MeSH secundário: Animais
Automação
Comportamento Animal/efeitos dos fármacos
Caenorhabditis elegans/efeitos dos fármacos
Quimiotaxia/efeitos dos fármacos
Cobre/farmacologia
Microscopia
Soluções/química
Gravação em Vídeo
[Pt] Tipo de publicação:JOURNAL ARTICLE; VIDEO-AUDIO MEDIA
[Nm] Nome de substância:
0 (Solutions); 789U1901C5 (Copper); S2QG84156O (cupric chloride)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180126
[Lr] Data última revisão:
180126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.3791/55963


  10 / 13998 MEDLINE  
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[PMID]:29286727
[Au] Autor:Segota I; Franck C
[Ad] Endereço:Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca 14853, USA.
[Ti] Título:Extracellular Processing of Molecular Gradients by Eukaryotic Cells Can Improve Gradient Detection Accuracy.
[So] Source:Phys Rev Lett;119(24):248101, 2017 Dec 15.
[Is] ISSN:1079-7114
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Eukaryotic cells sense molecular gradients by measuring spatial concentration variation through the difference in the number of occupied receptors to which molecules can bind. They also secrete enzymes that degrade these molecules, and it is presently not well understood how this affects the local gradient perceived by cells. Numerical and analytical results show that these enzymes can substantially increase the signal-to-noise ratio of the receptor difference and allow cells to respond to a much broader range of molecular concentrations and gradients than they would without these enzymes.
[Mh] Termos MeSH primário: AMP Cíclico/metabolismo
Células Eucarióticas/metabolismo
Modelos Biológicos
Diester Fosfórico Hidrolases/metabolismo
[Mh] Termos MeSH secundário: Ácido Aspártico Endopeptidases/metabolismo
Quimiotaxia
Dictyostelium/enzimologia
Dictyostelium/metabolismo
Difusão
Células Eucarióticas/citologia
Células Eucarióticas/enzimologia
Saccharomyces cerevisiae/enzimologia
Saccharomyces cerevisiae/metabolismo
Proteínas de Saccharomyces cerevisiae/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Saccharomyces cerevisiae Proteins); E0399OZS9N (Cyclic AMP); EC 3.1.4.- (Phosphoric Diester Hydrolases); EC 3.4.23.- (Aspartic Acid Endopeptidases); EC 3.4.23.- (BAR1 protein, S cerevisiae)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180109
[Lr] Data última revisão:
180109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171230
[St] Status:MEDLINE
[do] DOI:10.1103/PhysRevLett.119.248101



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