scholarly journals Visual-olfactory integration in the human disease vector mosquito, Aedes aegypti

2019 ◽  
Author(s):  
Clément Vinauger ◽  
Floris Van Breugel ◽  
Lauren T. Locke ◽  
Kennedy K.S. Tobin ◽  
Michael H. Dickinson ◽  
...  

SummaryMosquitoes rely on the integration of multiple sensory cues, including olfactory, visual, and thermal stimuli, to detect, identify and locate their hosts [1–4]. Although we increasingly know more about the role of chemosensory behaviours in mediating mosquito-host interactions [1], the role of visual cues remains comparatively less studied [3], and how the combination of olfactory and visual information is integrated in the mosquito brain remains unknown. In the present study, we used a tethered-flight LED arena, which allowed for quantitative control over the stimuli, to show that CO2 exposure affects target-tracking responses, but not responses to large-field visual stimuli. In addition, we show that CO2 modulates behavioural responses to visual objects in a time-dependent manner. To gain insight into the neural basis of this olfactory and visual coupling, we conducted two-photon microscopy experiments in a new GCaMP6s-expressing mosquito line. Imaging revealed that the majority of ROIs in the lobula region of the optic lobe exhibited strong responses to small-field stimuli, but showed little response to a large-field stimulus. Approximately 20% of the neurons we imaged were modulated when an attractive odour preceded the visual stimulus; these same neurons also elicited a small response when the odour was presented alone. By contrast, imaging in the antennal lobe revealed no modulation when visual stimuli were presented before or after the olfactory stimulus. Together, our results are the first to reveal the dynamics of olfactory modulation in visually evoked behaviours of mosquitoes, and suggest that coupling between these sensory systems is asymmetrical and time-dependent.


2021 ◽  
pp. 1-23
Author(s):  
Hye-Jung CHO ◽  
Jieun KIAER ◽  
Naya CHOI ◽  
Jieun SONG

Abstract In Korean language, questions containing ambiguous wh-words may be interpreted as either wh-questions or yes-no questions. This study investigated 43 Korean three-year-olds’ ability to disambiguate eight indeterminate questions using prosodic and visual cues. The intonation of each question provided a cue as to whether it should be interpreted as a wh-question or a yes-no question. The questions were presented alongside picture stimuli, which acted as either a matched (presentation of corresponding auditory-visual stimuli) or a mismatched contextual cue (presentation conflicting auditory-visual stimuli). Like adults, the children preferred to comprehend questions involving ambiguous wh-words as wh-questions, rather than yes-no questions. In addition, children were as effective as adults in disambiguating indeterminate questions using prosodic cues regardless of the visual cue. However, when confronted with conflicting auditory-visual stimuli (mismatched), the quality of children's responses was less accurate than adults’ responses.



2017 ◽  
Vol 313 (5) ◽  
pp. L899-L915 ◽  
Author(s):  
Fumiaki Kato ◽  
Seiichiro Sakao ◽  
Takao Takeuchi ◽  
Toshio Suzuki ◽  
Rintaro Nishimura ◽  
...  

Pulmonary arterial hypertension (PAH) is characterized by progressive obstructive remodeling of pulmonary arteries. However, no reports have described the causative role of the autophagic pathway in pulmonary vascular endothelial cell (EC) alterations associated with PAH. This study investigated the time-dependent role of the autophagic pathway in pulmonary vascular ECs and pulmonary vascular EC kinesis in a severe PAH rat model (Sugen/hypoxia rat) and evaluated whether timely induction of the autophagic pathway by rapamycin improves PAH. Hemodynamic and histological examinations as well as flow cytometry of pulmonary vascular EC-related autophagic pathways and pulmonary vascular EC kinetics in lung cell suspensions were performed. The time-dependent and therapeutic effects of rapamycin on the autophagic pathway were also assessed. Sugen/hypoxia rats treated with the vascular endothelial growth factor receptor blocker SU5416 showed increased right ventricular systolic pressure (RVSP) and numbers of obstructive vessels due to increased pulmonary vascular remodeling. The expression of the autophagic marker LC3 in ECs also changed in a time-dependent manner, in parallel with proliferation and apoptotic markers as assessed by flow cytometry. These results suggest the presence of cross talk between pulmonary vascular remodeling and the autophagic pathway, especially in small vascular lesions. Moreover, treatment of Sugen/hypoxia rats with rapamycin after SU5416 injection activated the autophagic pathway and improved the balance between cell proliferation and apoptosis in pulmonary vascular ECs to reduce RVSP and pulmonary vascular remodeling. These results suggested that the autophagic pathway can suppress PAH progression and that rapamycin-dependent activation of the autophagic pathway could ameliorate PAH.



2018 ◽  
Vol 40 (1) ◽  
pp. 93-109
Author(s):  
YI ZHENG ◽  
ARTHUR G. SAMUEL

AbstractIt has been documented that lipreading facilitates the understanding of difficult speech, such as noisy speech and time-compressed speech. However, relatively little work has addressed the role of visual information in perceiving accented speech, another type of difficult speech. In this study, we specifically focus on accented word recognition. One hundred forty-two native English speakers made lexical decision judgments on English words or nonwords produced by speakers with Mandarin Chinese accents. The stimuli were presented as either as videos that were of a relatively far speaker or as videos in which we zoomed in on the speaker’s head. Consistent with studies of degraded speech, listeners were more accurate at recognizing accented words when they saw lip movements from the closer apparent distance. The effect of apparent distance tended to be larger under nonoptimal conditions: when stimuli were nonwords than words, and when stimuli were produced by a speaker who had a relatively strong accent. However, we did not find any influence of listeners’ prior experience with Chinese accented speech, suggesting that cross-talker generalization is limited. The current study provides practical suggestions for effective communication between native and nonnative speakers: visual information is useful, and it is more useful in some circumstances than others.



Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1734-1734
Author(s):  
Orit Uziel ◽  
Zinab Sarsur- Amer ◽  
Einat Beery ◽  
Pia Raanani ◽  
Uri Rozovski

Studies from recent years unraveled the role of monocytes and T-cells in the pathogenesis of chronic lymphocytic leukemia (CLL). The role of other immune cells in the pathobiology of CLL is less known. Specifically, whether B-cells, the normal counterpart of CLL cells play a role in CLL is unknown. Nevertheless, since both CLL cells and wild type B-cells reside in lymphatic organs and travel in blood, they either share or compete over common environmental resources. According to the cell competition theory, a sensing mechanism measures the relative fitness of a cell and ensures the elimination of cells deemed to be less fit then their neighbors. Since constitutive activation of intracellular pathways protect CLL cells from apoptosis, the cell competition theory predicts that compared with normal B-cells these cells are sensed as "super fit" and B-cells, the less fit counterparts, are eliminated. Yet, what delivers this massage across a population of cells is unknown. Exosomes are nanosized particles that are secreted by various types of cells. Exosomes carry a cargo of proteins and different types of RNA. They travel in body fluids and are taken up by cells in their vicinity. Since cancer cells including CLL cells secrete exosomes, we have formulated our hypothesis, namely, that exosomes derived from CLL cells are the vehicles that carry a death massage to wild type B-cells. To test this hypothesis, we isolated CLL cells from 3 previously untreated patients with CLL. We then grew these cells in exosome free media for 72 hours and harvested the exosomes by ultracentrifugation. We used NanoSight tracking analysis, Western immunoblotting for CD63, a common exosomal marker, and electron microscopy imaging studies to ensure that our pellet include the typical 100nm exosomal particles. Subsequently, we subjected normal B-cells derived from healthy volunteers to CLL derived exosomes stained by FM-143 dye. Using flow cytometry we found that exosomes are taken up by normal B-cells in a dose- and time- dependent manner. Double staining of the recipient B-cells to Annexin/PI revealed that exosomes induce apoptosis of these cells in a dose- and time- dependent manner. We then used RNA-seq to trace the changes in the molecular makeup of B-cells after exosomal uptake?? they took up exosomes. We found 24 transcripts that were differentially expressed (11 that were upregulated and 13 that were downregulated). We then verified the array results by quantitative real-time PCR for four of these genes. Among the top transcripts that were upregulated in exosome-positive B-cells is SMAD6. Because the upregulation of the SMAD family members including SMAD6 is associated with the induction of apoptosis in various malignant and non-malignant cells we wondered whether the upregulation of SMAD6 also induces apoptosis in normal B-cells. To test this, we transfected normal B-cells with SMAD6 containing vector and verified by RT-PCR that level of SMAD6 transcript were upregulated and by Western immunoblotting that levels of SMAD6 protein are upregulated as well. As expected, the rate of apoptosis was higher, and the rates of viable cells and proliferating cells were significantly lower in SMAD6-transfected B-cells. Taken together, we show here that CLL cells secrete exosomes that function as "Trojan horses". Once they are taken up by normal B-cells they induce SMAD6-dependent apoptosis. In this way the neoplastic cells may actively eliminate their competitors and take over the common environmental resources. Disclosures No relevant conflicts of interest to declare.



Neurology ◽  
2018 ◽  
Vol 90 (11) ◽  
pp. e977-e984 ◽  
Author(s):  
Motoyasu Honma ◽  
Yuri Masaoka ◽  
Takeshi Kuroda ◽  
Akinori Futamura ◽  
Azusa Shiromaru ◽  
...  

ObjectiveTo determine whether Parkinson disease (PD) affects cross-modal function of vision and olfaction because it is known that PD impairs various cognitive functions, including olfaction.MethodsWe conducted behavioral experiments to identify the influence of PD on cross-modal function by contrasting patient performance with age-matched normal controls (NCs). We showed visual effects on the strength and preference of odor by manipulating semantic connections between picture/odorant pairs. In addition, we used brain imaging to identify the role of striatal presynaptic dopamine transporter (DaT) deficits.ResultsWe found that odor evaluation in participants with PD was unaffected by visual information, while NCs overestimated smell when sniffing odorless liquid while viewing pleasant/unpleasant visual cues. Furthermore, DaT deficit in striatum, for the posterior putamen in particular, correlated to few visual effects in participants with PD.ConclusionsThese findings suggest that PD impairs cross-modal function of vision/olfaction as a result of posterior putamen deficit. This cross-modal dysfunction may serve as the basis of a novel precursor assessment of PD.



Cancers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 345
Author(s):  
Xi-Feng Jin ◽  
Gerald Spöttl ◽  
Julian Maurer ◽  
Svenja Nölting ◽  
Christoph Josef Auernhammer

Background and aims: Inhibition of Wnt/β-catenin signaling by specific inhibitors is currently being investigated as an antitumoral strategy for various cancers. The role of Wnt/β-catenin signaling in neuroendocrine tumors still needs to be further investigated. Methods: This study investigated the antitumor activity of the porcupine (PORCN) inhibitor WNT974 and the β-catenin inhibitor PRI-724 in human neuroendocrine tumor (NET) cell lines BON1, QGP-1, and NCI-H727 in vitro. NET cells were treated with WNT974, PRI-724, or small interfering ribonucleic acids against β-catenin, and subsequent analyses included cell viability assays, flow cytometric cell cycle analysis, caspase3/7 assays and Western blot analysis. Results: Treatment of NET cells with WNT974 significantly reduced NET cell viability in a dose- and time-dependent manner by inducing NET cell cycle arrest at the G1 and G2/M phases without inducing apoptosis. WNT974 primarily blocked Wnt/β-catenin signaling by the dose- and time-dependent downregulation of low-density lipoprotein receptor-related protein 6 (LRP6) phosphorylation and non-phosphorylated β-catenin and total β-catenin, as well as the genes targeting the latter (c-Myc and cyclinD1). Furthermore, the WNT974-induced reduction of NET cell viability occurred through the inhibition of GSK-3-dependent or independent signaling (including pAKT/mTOR, pEGFR and pIGFR signaling). Similarly, treatment of NET cells with the β-catenin inhibitor PRI-724 caused significant growth inhibition, while the knockdown of β-catenin expression by siRNA reduced NET tumor cell viability of BON1 cells but not of NCI-H727 cells. Conclusions: The PORCN inhibitor WNT974 possesses antitumor properties in NET cell lines by inhibiting Wnt and related signaling. In addition, the β-catenin inhibitor PRI-724 possesses antitumor properties in NET cell lines. Future studies are needed to determine the role of Wnt/β-catenin signaling in NET as a potential therapeutic target.



2017 ◽  
Vol 30 (7-8) ◽  
pp. 653-679 ◽  
Author(s):  
Nida Latif ◽  
Agnès Alsius ◽  
K. G. Munhall

During conversations, we engage in turn-taking behaviour that proceeds back and forth effortlessly as we communicate. In any given day, we participate in numerous face-to-face interactions that contain social cues from our partner and we interpret these cues to rapidly identify whether it is appropriate to speak. Although the benefit provided by visual cues has been well established in several areas of communication, the use of visual information to make turn-taking decisions during conversation is unclear. Here we conducted two experiments to investigate the role of visual information in identifying conversational turn exchanges. We presented clips containing single utterances spoken by single individuals engaged in a natural conversation with another. These utterances were from either right before a turn exchange (i.e., when the current talker would finish and the other would begin) or were utterances where the same talker would continue speaking. In Experiment 1, participants were presented audiovisual, auditory-only and visual-only versions of our stimuli and identified whether a turn exchange would occur or not. We demonstrated that although participants could identify turn exchanges with unimodal information alone, they performed best in the audiovisual modality. In Experiment 2, we presented participants audiovisual turn exchanges where the talker, the listener or both were visible. We showed that participants suffered a cost at identifying turns exchanges when visual cues from the listener were not available. Overall, we demonstrate that although auditory information is sufficient for successful conversation, visual information plays an important role in the overall efficiency of communication.



2022 ◽  
Author(s):  
Nicole E Wynne ◽  
Karthikeyan Chandrasegaran ◽  
Lauren Fryzlewicz ◽  
Clément Vinauger

The diurnal mosquitoes Aedes aegypti are vectors of several arboviruses, including dengue, yellow fever, and Zika viruses. To find a host to feed on, they rely on the sophisticated integration of olfactory, visual, thermal, and gustatory cues reluctantly emitted by the hosts. If detected by their target, this latter may display defensive behaviors that mosquitoes need to be able to detect and escape. In humans, a typical response is a swat of the hand, which generates both mechanical and visual perturbations aimed at a mosquito. While the neuro-sensory mechanisms underlying the approach to the host have been the focus of numerous studies, the cues used by mosquitoes to detect and identify a potential threat remain largely understudied. In particular, the role of vision in mediating mosquitoes' ability to escape defensive hosts has yet to be analyzed. Here, we used programmable visual displays to generate expanding objects sharing characteristics with the visual component of an approaching hand and quantified the behavioral response of female mosquitoes. Results show that Ae. aegypti is capable of using visual information to decide whether to feed on an artificial host mimic. Stimulations delivered in a LED flight arena further reveal that landed females Ae. aegypti display a stereotypical escape strategy by taking off at an angle that is a function of the distance and direction of stimulus introduction. Altogether, this study demonstrates mosquitoes can use isolated visual cues to detect and avoid a potential threat.



2019 ◽  
Author(s):  
Meike Scheller ◽  
Francine Matorres ◽  
Lucy Tompkins ◽  
Anthony C. Little ◽  
Alexandra A. de Sousa

Cross-cultural research has repeatedly demonstrated sex differences in the importance of different partner characteristics when choosing a mate. Men typically report higher preferences for younger, more physically attractive women, while women prefer men that are wealthier and of higher status. As the assessment of such partner characteristics often relies on visual cues, this raises the question whether visual experience is necessary for sex-specific mate preferences to develop. To shed more light onto the emergence of sex differences in mate choice, the current study assessed how preferences for attractiveness, resources, and personality factors differ between sighted and blind individuals using an online questionnaire. We further investigate the role of social factors and sensory cue selection in these sex differences. Our sample consisted of 94 sighted and blind participants with different ages of blindness-onset, 19 blind/28 sighted males, and 19 blind/28 sighted females. Results replicated well-documented findings in the sighted, with men placing more importance on physical attractiveness and women placing more importance on status and resources. However, while physical attractiveness was less important to blind men, blind women considered physical attractiveness as important as sighted women. The importance of a high status and likeable personality was not influenced by sightedness. Blind individuals considered auditory cues more important than visual cues, while sighted males showed the opposite pattern. Further, relationship status and indirect, social influences were related to preferences. Overall, our findings shed light on the availability of visual information for the emergence of sex differences in mate preference.



Perception ◽  
10.1068/p7153 ◽  
2012 ◽  
Vol 41 (2) ◽  
pp. 175-192 ◽  
Author(s):  
Esteban R Calcagno ◽  
Ezequiel L Abregú ◽  
Manuel C Eguía ◽  
Ramiro Vergara

In humans, multisensory interaction is an important strategy for improving the detection of stimuli of different nature and reducing the variability of response. It is known that the presence of visual information affects the auditory perception in the horizontal plane (azimuth), but there are few researches that study the influence of vision in the auditory distance perception. In general, the data obtained from these studies are contradictory and do not completely define the way in which visual cues affect the apparent distance of a sound source. Here psychophysical experiments on auditory distance perception in humans are performed, including and excluding visual cues. The results show that the apparent distance from the source is affected by the presence of visual information and that subjects can store in their memory a representation of the environment that later improves the perception of distance.



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