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1.
Genes Brain Behav ; 20(8): e12772, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34672079

RESUMO

Male sexual behavior in Drosophila melanogaster, largely controlled by the fruitless (fru) gene encoding the male specific FruM protein, is among the best studied animal behaviors. Although substantial studies suggest that FruM specifies a neuronal circuitry governing all aspects of male sexual behaviors, recent findings show that FruM is not absolutely necessary for such behaviors. We propose that another regulatory gene doublesex encoding the male-specific DsxM protein builds a core neuronal circuitry that possesses the potential for courtship, which could be either induced through adult social experience or innately manifested during development by FruM expression in a broader neuronal circuitry. FruM expression levels and patterns determine the modes of courtship behavior from innate heterosexual, homosexual, bisexual, to learned courtship. We discuss how FruM expression is regulated by hormones and social experiences and tunes functional flexibility of the sex circuitry. We propose that regulatory genes hierarchically build the potential for innate and learned aspects of courtship behaviors, and expression changes of these regulatory genes among different individuals and species with different social experiences ultimately lead to behavioral diversification.

3.
Neural Plast ; 2021: 1198072, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567107

RESUMO

Recent clinical practice has found that the spike-wave discharge (SWD) scopes of absence seizures change from small cortical region to large thalamocortical networks, which has also been proved by theoretical simulation. The best biophysics explanation is that there are interactions between coupled cortico-thalamic and thalamocortical circuits. To agree with experiment results and describe the phenomena better, we constructed a coupled thalamocortical model with bidirectional channel (CTMBC) to account for the causes of absence seizures which are connected by the principle of two-way communication of neural pathways. By adjusting the coupling strength of bidirectional pathways, the spike-wave discharges are reproduced. Regulatory mechanism for absence seizures is further applied to CTMBC via four different targeted therapy schemes, such as deep brain stimulation (DBS), charge-balanced biphasic pulse (CBBP), coordinated reset stimulation (CRS) 1 : 0, and (CRS) 3 : 2. The new CTMBC model shows that neurodiversity in bidirectional interactive channel could supply theory reference for the bidirectional communication mode of thalamocortical networks and the hypothesis validation of pathogenesis.

4.
PLoS Genet ; 17(8): e1009724, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34398892

RESUMO

Feeding is essential for animal survival and reproduction and is regulated by both internal states and external stimuli. However, little is known about how internal states influence the perception of external sensory cues that regulate feeding behavior. Here, we investigated the neuronal and molecular mechanisms behind nutritional state-mediated regulation of gustatory perception in control of feeding behavior in the brown planthopper and Drosophila. We found that feeding increases the expression of the cholecystokinin-like peptide, sulfakinin (SK), and the activity of a set of SK-expressing neurons. Starvation elevates the transcription of the sugar receptor Gr64f and SK negatively regulates the expression of Gr64f in both insects. Interestingly, we found that one of the two known SK receptors, CCKLR-17D3, is expressed by some of Gr64f-expressing neurons in the proboscis and proleg tarsi. Thus, we have identified SK as a neuropeptide signal in a neuronal circuitry that responds to food intake, and regulates feeding behavior by diminishing gustatory receptor gene expression and activity of sweet sensing GRNs. Our findings demonstrate one nutritional state-dependent pathway that modulates sweet perception and thereby feeding behavior, but our experiments cannot exclude further parallel pathways. Importantly, we show that the underlying mechanisms are conserved in the two distantly related insect species.

5.
ASN Neuro ; 13: 17590914211015033, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33951964

RESUMO

Antioxidants and related compounds are anti-inflammatory and exhibit great potential in promoting human health. They are also often considered to be important elements in the process of neurodegeneration. Here we describe a antioxidant blend of Curcumin and Broccoli Seed Extract (BSE). Flies treated with the blend exhibit extended lifespan. RNA-seq analysis of samples from adult fly brains reveals a wide array of new genes with differential expression upon treatment with the blend. Interestingly, abolishing expression of some of the identified genes in dopaminergic (DA) neurons does not affect DA neuron number. Taken together, our findings reveal an antioxidant blend that promotes fly longevity and exhibits protective effect over neurodegeneration, demonstrating the importance of antioxidants in health and pathology.


Assuntos
Antioxidantes/administração & dosagem , Brassica , Curcumina/administração & dosagem , Longevidade/efeitos dos fármacos , Degeneração Neural/prevenção & controle , Fármacos Neuroprotetores/administração & dosagem , Animais , Antioxidantes/isolamento & purificação , Curcumina/isolamento & purificação , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Relação Dose-Resposta a Droga , Drosophila melanogaster , Feminino , Longevidade/fisiologia , Masculino , Degeneração Neural/genética , Degeneração Neural/patologia , Fármacos Neuroprotetores/isolamento & purificação , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Sementes
6.
Nat Commun ; 12(1): 2698, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976215

RESUMO

Gut microbiome profoundly affects many aspects of host physiology and behaviors. Here we report that gut microbiome modulates aggressive behaviors in Drosophila. We found that germ-free males showed substantial decrease in inter-male aggression, which could be rescued by microbial re-colonization. These germ-free males are not as competitive as wild-type males for mating with females, although they displayed regular levels of locomotor and courtship behaviors. We further found that Drosophila microbiome interacted with diet during a critical developmental period for the proper expression of octopamine and manifestation of aggression in adult males. These findings provide insights into how gut microbiome modulates specific host behaviors through interaction with diet during development.


Assuntos
Agressão/fisiologia , Drosophila melanogaster/fisiologia , Microbioma Gastrointestinal/fisiologia , Octopamina/metabolismo , Comportamento Sexual Animal/fisiologia , Animais , Bactérias/classificação , Bactérias/genética , Encéfalo/citologia , Encéfalo/metabolismo , Encéfalo/fisiologia , Drosophila melanogaster/metabolismo , Drosophila melanogaster/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Masculino , Atividade Motora/fisiologia , Neurônios/metabolismo , Neurônios/fisiologia , RNA Ribossômico 16S/genética , Transdução de Sinais/fisiologia , Organismos Livres de Patógenos Específicos
7.
Surg Endosc ; 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33770278

RESUMO

OBJECTIVE: This study evaluated the application of the bipolar electrocoagulation catheter via a peripheral-to-central (3 + 1) technique, relative to directly pressing only at the center of the bleeding site (direct-stroke), to effect endoscopic hemostasis of acute non-varicose gastrointestinal bleeding (ANVUGIB). METHODS: Patients (n = 148) with endoscopically diagnosed ANVUGIB were randomly apportioned to receive treatment by 3 + 1 (n = 78) or direct-stroke (n = 70) application of the bipolar electrocoagulation catheter. The 3 + 1 strategy required pressing at3 narrowly restricted sites equidistant peripheral and center to the site of bleeding. The rates of initial success, hemostasis time, and number of compressions were compared according to intention-to-treat (ITT) or per protocol (PP). RESULTS: The ITT (PP) rate of initial hemostatic success in patients receiving the 3 + 1 catheter was 91.02% (95.9%); and for the direct-stroke group was 71.42% (76.9%). For Forrest IIa lesions specifically, these rates were respectively 91.70% (97.1%) and 63.9% (67.6%). The ITT (PP) hemostasis times of the 3 + 1 and direct-stroke groups were 10.96 ± 3.28 (10.65 ± 2.90) and 14.27 ± 6.58 (14.12 ± 6.67) min; and the number of compressions numbered 5.73 ± 1.98 (5.42 ± 1.46) and 6.47 ± 2.82 (6.16 ± 2.47). CONCLUSION: During thermocoagulation treatment of ANVUGIB via bipolar electrocoagulation catheter, the 3 + 1 strategy showed a significantly higher rate of successful initial hemostasis relative to the direct-stroke technique, and shorter hemostasis time, with no increase in total procedural steps.

8.
Elife ; 102021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33463521

RESUMO

Drosophila male courtship is controlled by the male-specific products of the fruitless (fruM) gene and its expressing neuronal circuitry. fruM is considered a master gene that controls all aspects of male courtship. By temporally and spatially manipulating fruM expression, we found that fruM is required during a critical developmental period for innate courtship toward females, while its function during adulthood is involved in inhibiting male-male courtship. By altering or eliminating fruM expression, we generated males that are innately heterosexual, homosexual, bisexual, or without innate courtship but could acquire such behavior in an experience-dependent manner. These findings show that fruM is not absolutely necessary for courtship but is critical during development to build a sex circuitry with reduced flexibility and enhanced efficiency, and provide a new view about how fruM tunes functional flexibility of a sex circuitry instead of switching on its function as conventionally viewed.

9.
Mol Psychiatry ; 26(7): 2964-2976, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33051604

RESUMO

Numerous studies have used human pluripotent stem cell-derived cerebral organoids to elucidate the mystery of human brain development and model neurological diseases in vitro, but the potential for grafted organoid-based therapy in vivo remains unknown. Here, we optimized a culturing protocol capable of efficiently generating small human cerebral organoids. After transplantation into the mouse medial prefrontal cortex, the grafted human cerebral organoids survived and extended projections over 4.5 mm in length to basal brain regions within 1 month. The transplanted cerebral organoids generated human glutamatergic neurons that acquired electrophysiological maturity in the mouse brain. Importantly, the grafted human cerebral organoids functionally integrated into pre-existing neural circuits by forming bidirectional synaptic connections with the mouse host neurons. Furthermore, compared to control mice, the mice transplanted with cerebral organoids showed an increase in freezing time in response to auditory conditioned stimuli, suggesting the potentiation of the startle fear response. Our study showed that subcortical projections can be established by microtransplantation and may provide crucial insights into the therapeutic potential of human cerebral organoids for neurological diseases.

10.
J Mater Chem B ; 9(2): 404-409, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33283827

RESUMO

Montmorillonite (MMT), as a naturally sourced and FDA-approved biomaterial, has attracted considerable attention due to its extensive application in biomedical areas, such as intestinal ailments, drug delivery, and additive manufacturing. In this work, two-dimensional montmorillonite (2D-MMT) ultrathin nanosheets were successfully prepared from sodium montmorillonite (Na-MMT) by utilizing a freeze-drying assisted method. Possessing a large specific surface area and increased number of exposed hydroxyl groups, 2D-MMT nanosheets exhibited better antibacterial ability than the original Na-MMT. More strikingly, we found that both 2D-MMT nanosheets and Na-MMT could generate reactive oxygen species (ROS) upon visible light illumination, which could promote their antibacterial efficiency. As a result, 2D-MMT nanosheets showed efficient antibacterial performance in the presence of light towards Escherichia coli with a simultaneous enhancement of surface adsorption and photodynamic ablation. What's more, a possible mechanism for ROS generation by MMT upon light illumination was first proposed in this work. The combination of the increased physical adsorption capacity and ROS generation ability of 2D-MMT nanosheets would help inspire the development of MMT as a promising antimicrobial candidate in the future.


Assuntos
Antibacterianos/metabolismo , Bentonita/química , Nanotecnologia/métodos , Fotoquimioterapia/métodos , Humanos , Espécies Reativas de Oxigênio
11.
Neurosci Bull ; 36(12): 1429-1440, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33174166

RESUMO

Some semelparous organisms in nature mate as many times as they can in a single reproductive episode before death, while most iteroparous species including humans avoid such suicidal reproductive behavior. Animals naturally pursue more sex and the possible fatal consequence of excessive sex must be orchestrated by negative feedback signals in iteroparous species, yet very little is known about the regulatory mechanisms. Here we used Drosophila male sexual behavior as a model system to study how excessive sex may kill males and how the nervous system reacts to prevent death by sex. We found that continuous sexual activity by activating the fruitless-expressing neurons induced a fixed multi-step behavioral pattern ending with male death. We further found negative feedback in the fly brain to prevent suicidal sexual behavior by expression changes of the neurotransmitters acetylcholine and gamma-aminobutyric acid, and neuropeptide F. These findings are crucial to understand the molecular underpinnings of how different organisms choose reproductive strategies and balance reproduction and survival.


Assuntos
Encéfalo/fisiologia , Drosophila/fisiologia , Retroalimentação Fisiológica , Neurônios/fisiologia , Comportamento Sexual Animal , Animais , Masculino , Reprodução
12.
Molecules ; 25(5)2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32155966

RESUMO

A nitrogen dioxide (NO2) photoacoustic sensor for environmental monitoring was developed using a low-cost high-power laser diode emitting at 450 nm. A compact low-noise photoacoustic detection module was designed to reduce the sensor size and to suppress noise. A LabVIEW-based control system was employed for the sensor. The parameters of the sensor were studied in detail in terms of laser power and operating pressure. The linearity of the sensor response with laser power and NO2 concentration confirms that saturation does not occur. At atmospheric pressure, a 3σ detection limit of 250 ppt (part per trillion by volume) was achieved with a 1-s averaging time, which corresponds to the specific detectivity of 3.173 × 10-9 W cm-1 Hz-1/2. A 72 h outdoor continuous on-line monitoring of environmental NO2 was implemented to demonstrate the reliability and validity of the developed NO2 sensor.


Assuntos
Monitoramento Ambiental/instrumentação , Dióxido de Nitrogênio/análise , Técnicas Fotoacústicas/instrumentação , Técnicas Fotoacústicas/métodos , Monitoramento Ambiental/métodos , Desenho de Equipamento , Lasers , Limite de Detecção , Pressão , Razão Sinal-Ruído , Vapor
14.
Nat Commun ; 10(1): 4770, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628317

RESUMO

Animals perform or terminate particular behaviors by integrating external cues and internal states through neural circuits. Identifying neural substrates and their molecular modulators promoting or inhibiting animal behaviors are key steps to understand how neural circuits control behaviors. Here, we identify the Cholecystokinin-like peptide Drosulfakinin (DSK) that functions at single-neuron resolution to suppress male sexual behavior in Drosophila. We found that Dsk neurons physiologically interact with male-specific P1 neurons, part of a command center for male sexual behaviors, and function oppositely to regulate multiple arousal-related behaviors including sex, sleep and spontaneous walking. We further found that the DSK-2 peptide functions through its receptor CCKLR-17D3 to suppress sexual behaviors in flies. Such a neuropeptide circuit largely overlaps with the fruitless-expressing neural circuit that governs most aspects of male sexual behaviors. Thus DSK/CCKLR signaling in the sex circuitry functions antagonistically with P1 neurons to balance arousal levels and modulate sexual behaviors.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Oligopeptídeos/metabolismo , Fatores de Transcrição/metabolismo , Animais , Animais Geneticamente Modificados , Nível de Alerta/fisiologia , Comunicação Celular/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Feminino , Locomoção/fisiologia , Masculino , Proteínas do Tecido Nervoso/genética , Neurônios/citologia , Neuropeptídeos/genética , Oligopeptídeos/genética , Comportamento Sexual Animal/fisiologia , Transdução de Sinais/genética , Sono/fisiologia , Fatores de Transcrição/genética
15.
Neurosci Bull ; 35(6): 1138, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31175640

RESUMO

In the original publication the fifth line starting with "… with circa 1000, 1000 neurons?" in section Concluding Remarks and Perspectives is incorrectly published. The correct text should read "… with circa 100, 000 neurons?"

16.
Neurosci Bull ; 35(6): 1058-1072, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31119647

RESUMO

Nervous systems endow animals with cognition and behavior. To understand how nervous systems control behavior, neural circuits mediating distinct functions need to be identified and characterized. With superior genetic manipulability, Drosophila is a model organism at the leading edge of neural circuit analysis. We briefly introduce the state-of-the-art genetic tools that permit precise labeling of neurons and their interconnectivity and investigating what is happening in the brain of a behaving animal and manipulating neurons to determine how behaviors are affected. Brain-wide wiring diagrams, created by light and electron microscopy, bring neural circuit analysis to a new level and scale. Studies enabled by these tools advances our understanding of the nervous system in relation to cognition and behavior.


Assuntos
Drosophila/fisiologia , Fenômenos Fisiológicos do Sistema Nervoso/genética , Animais , Comportamento Animal/fisiologia , Encéfalo/metabolismo , Técnicas Genéticas , Modelos Animais , Rede Nervosa , Sistema Nervoso , Neurônios , Neurociências/métodos
17.
R Soc Open Sci ; 6(1): 181090, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30800362

RESUMO

A new red fluorescent probe 1 based on BODIPY skeleton has been successfully synthesized through introduction of 2-(thiophen-2-yl) quinoline moiety at meso- and 3-position, which exhibits excellent optical performance, including high fluorescence quantum yield, large pseudo Stokes' shift as well as high selectivity and sensitivity towards iridium (III) ion in aqueous solution and in living cells.

18.
Surg Endosc ; 33(12): 4122-4127, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30805784

RESUMO

AIM: To investigate the effectiveness of over-the-scope-clip (OTSC)-based endoscopic closure in patients with perforated peptic ulcer (PPU). METHODS: One hundred six patients diagnosed with PPU were treated with either OTSC (n = 26) or conservative treatments (n = 80), respectively. The outcome assessments included technical success rate, clinical success rate, post-treatment complications after 1 month, mortality rate, time to resume oral feeding, length of hospital stay, and the administration of antibiotics. RESULTS: In the OTSC group, technical and clinical success was achieved in 100% of patients without any complications, including death, incomplete closure, duodenal obstruction, and gastrointestinal bleeding, with a median operation time of 10 min. All patients in the OTSC group were discharged, while the mortality rate in the control group was 13.8%. Subsequent surgeries were required in 30% of patients in the control group. The median times to resume oral feeding were 3.5 (interquartile range [IQR] 2.0-5.25) days in the OTSC group and 7.0 (IQR 5.0-9.0) days in the control group (p < 0.001). One month post-procedure, 30% (24/80) of patients in the control group and 0 (0/26) in the OTSC group required additional operations (p < 0.001). No significant difference was found in the length of the hospital stay and the administration of antibiotics between the two groups (p > 0.05). CONCLUSIONS: OTSC-based endoscopic technique, with a high clinical success rate and a shorter time to resume oral feeding, was effective in achieving closure of PPU with a diameter < 15 mm.


Assuntos
Úlcera Péptica Perfurada/cirurgia , Instrumentos Cirúrgicos , Adulto , Feminino , Hemostase Endoscópica/instrumentação , Hemostase Endoscópica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Cirurgia Endoscópica por Orifício Natural/instrumentação , Cirurgia Endoscópica por Orifício Natural/métodos , Úlcera Péptica Perfurada/etiologia , Estudos Retrospectivos , Resultado do Tratamento
19.
Pest Manag Sci ; 75(6): 1606-1620, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30515974

RESUMO

BACKGROUND: The white-backed planthopper (WBPH) Sogatella furcifera, the brown planthopper (BPH) Nilaparvata lugens, and the small brown planthopper (SBPH) Laodelphax striatellus are three notorious rice pests that cause annual losses in rice yield through sap-sucking and virus transmission. Odorant-binding proteins (OBPs) are crucial olfactory genes involved in host-seeking behavior. RESULTS: We discovered the presence of 12, 12, and 16 OBPs in WBPH, BPH, and SBPH, respectively, including two novel OBPs in BPH and seven novel OBPs in SBPH. Phylogenetic analysis indicated that most of these OBPs have homologous genes, and one group (SfurOBP11, NlugOBP8, and LstrOBP2) show a slower evolution rate and are more conserved. Further, in vitro binding studies demonstrated that the three OBPs have similar binding affinities for some rice plant volatiles. Finally, RNA interference (RNAi) successfully inhibited the mRNA expression of the three OBPs, and in vivo behavioral tests showed that the OBP-deficient rice planthoppers were partly anosmic and lost some of their ability to locate rice plants. CONCLUSION: These results demonstrate the crucial role of the rice planthopper OBP genes in seeking rice plants. This information complements the current genetic resources for the development of RNAi-based transgenic rice and other pest management technologies. © 2018 Society of Chemical Industry.


Assuntos
Evolução Molecular , Hemípteros , Proteínas de Insetos/metabolismo , Receptores Odorantes/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Insetos/química , Proteínas de Insetos/genética , Modelos Moleculares , Filogenia , Conformação Proteica , Receptores Odorantes/química , Receptores Odorantes/genética , Especificidade da Espécie
20.
Pestic Biochem Physiol ; 152: 1-7, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30497699

RESUMO

The white-backed planthopper (WBPH) Sogatella furcifera is a notorious rice pest in Asia. Olfaction is crucial for the WBPH to seek and locate rice plants. However, its mechanism is still not fully understood. Chemosensory proteins (CSPs) are some of the important olfactory-related proteins. In this study, we first used a bacterial system to successfully express the recombinant, antennae-enriched protein SfurCSP5. Further, competitive fluorescence binding assays with 86 candidate ligands, including some known rice plant volatiles, showed that SfurCSP5 has high affinities for 2-tridecanone, 2-pentadecanone, and ß-ionone, which are known to be present in volatile mixtures that can attract rice planthoppers, and produced Ki values of 4.89, 4.09, and 1.39 µmol/L, respectively. Additionally, homology modeling of the protein structure of SfurCSP5 showed that it possesses five α-helixes (α-1, α-2, α-3, α-4, and α-5), which is a non-typical feature of the insect CSPs. Finally, ligand docking results revealed that Leu-44, Ile-64, Phe-90, Trp-98, and Phe-101 are five hydrophobic residues that interact with all of the ligands, indicating their key involvement in the binding of SfurCSP5. Our study lays the foundation for an understanding of the olfaction mechanism of rice planthoppers.


Assuntos
Hemípteros/fisiologia , Proteínas de Insetos/fisiologia , Compostos Fitoquímicos/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Animais , Antenas de Artrópodes/fisiologia , Proteínas de Insetos/química , Ligantes , Modelos Moleculares , Percepção Olfatória , Oryza/metabolismo , Ligação Proteica , Conformação Proteica
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