Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
bioRxiv ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38106147

RESUMO

Courtship interactions are remarkably diverse in form and complexity among species. How neural circuits evolve to encode new behaviors that are functionally integrated into these dynamic social interactions is unknown. Here we report a recently originated female sexual behavior in the island endemic Drosophila species D. santomea, where females signal receptivity to male courtship songs by spreading their wings, which in turn promotes prolonged songs in courting males. Copulation success depends on this female signal and correlates with males' ability to adjust his singing in such a social feedback loop. Functional comparison of sexual circuitry across species suggests that a pair of descending neurons, which integrates male song stimuli and female internal state to control a conserved female abdominal behavior, drives wing spreading in D. santomea. This co-option occurred through the refinement of a pre-existing, plastic circuit that can be optogenetically activated in an outgroup species. Combined, our results show that the ancestral potential of a socially-tuned key circuit node to engage the wing motor program facilitates the expression of a new female behavior in appropriate sensory and motivational contexts. More broadly, our work provides insights into the evolution of social behaviors, particularly female behaviors, and the underlying neural mechanisms.

2.
Adv Sci (Weinh) ; 10(17): e2300845, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37132589

RESUMO

Plumbene, with a structure similar to graphene, is expected to possess a strong spin-orbit coupling and thus enhances its superconducting critical temperature (Tc ). In this work, a buckled plumbene-Au Kagome superstructure grown by depositing Au on Pb(111) is investigated. The superconducting gap monitored by temperature-dependent scanning tunneling microscopy/spectroscopy shows that the buckled plumbene-Au Kagome superstructure not only has an enhanced Tc with respect to that of a monolayer Pb but also possesses a higher value than what owned by a bulk Pb substrate. By combining angle-resolved photoemission spectroscopy with density functional theory, the monolayer Au-intercalated low-buckled plumbene sandwiched between the top Au Kagome layer and the bottom Pb(111) substrate is confirmed and the electron-phonon coupling-enhanced superconductivity is revealed. This work demonstrates that a buckled plumbene-Au Kagome superstructure can enhance superconducting Tc and Rashba effect, effectively triggering the novel properties of a plumbene.

3.
ACS Nano ; 16(9): 14918-14924, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36036754

RESUMO

Monolayer transition metal dichalcogenides offer an appropriate platform for developing advanced electronics beyond graphene. Similar to two-dimensional molecular frameworks, the electronic properties of such monolayers can be sensitive to perturbations from the surroundings; the implied tunability of electronic structure is of great interest. Using scanning tunneling microscopy/spectroscopy, we demonstrated a bandgap engineering technique in two monolayer materials, MoS2 and PtTe2, with the tunneling current as a control parameter. The bandgap of monolayer MoS2 decreases logarithmically by the increasing tunneling current, indicating an electric-field-induced gap renormalization effect. Monolayer PtTe2, by contrast, exhibits a much stronger gap reduction, and a reversible semiconductor-to-metal transition occurs at a moderate tunneling current. This unusual switching behavior of monolayer PtTe2, not seen in bulk semimetallic PtTe2, can be attributed to its surface electronic structure that can readily couple to the tunneling tip, as demonstrated by theoretical calculations.

4.
ACS Nano ; 14(4): 4963-4972, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32233458

RESUMO

Palladium diselenide (PdSe2), a peculiar noble metal dichalcogenide, has emerged as a new two-dimensional material with high predicted carrier mobility and a widely tunable band gap for device applications. The inherent in-plane anisotropy endowed by the pentagonal structure further renders PdSe2 promising for novel electronic, photonic, and thermoelectric applications. However, the direct synthesis of few-layer PdSe2 is still challenging and rarely reported. Here, we demonstrate that few-layer, single-crystal PdSe2 flakes can be synthesized at a relatively low growth temperature (300 °C) on sapphire substrates using low-pressure chemical vapor deposition (CVD). The well-defined rectangular domain shape and precisely determined layer number of the CVD-grown PdSe2 enable us to investigate their layer-dependent and in-plane anisotropic properties. The experimentally determined layer-dependent band gap shrinkage combined with first-principle calculations suggest that the interlayer interaction is weaker in few-layer PdSe2 in comparison with that in bulk crystals. Field-effect transistors based on the CVD-grown PdSe2 also show performances comparable to those based on exfoliated samples. The low-temperature synthesis method reported here provides a feasible approach to fabricate high-quality few-layer PdSe2 for device applications.

5.
PLoS One ; 10(4): e0122087, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25830357

RESUMO

Cognitive impairments severely affect the quality of life of patients who undergo brain irradiation, and there are no effective preventive strategies. In this study, we examined the therapeutic potential of electroacupuncture (EA) administered immediately after brain irradiation in rats. We detected changes in cognitive function, neurogenesis, and synaptic density at different time points after irradiation, but found that EA could protect the blood-brain barrier (BBB), inhibit neuroinflammatory cytokine expression, upregulate angiogenic cytokine expression, and modulate the levels of neurotransmitter receptors and neuropeptides in the early phase. Moreover, EA protected spatial memory and recognition in the delayed phase. At the cellular/molecular level, the preventative effect of EA on cognitive dysfunction was not dependent on hippocampal neurogenesis; rather, it was related to synaptophysin expression. Our results suggest that EA applied immediately after brain irradiation can prevent cognitive impairments by protecting against the early changes induced by irradiation and may be a novel approach for preventing or ameliorating cognitive impairments in patients with brain tumors who require radiotherapy.


Assuntos
Transtornos Cognitivos/prevenção & controle , Eletroacupuntura , Lesões Experimentais por Radiação/prevenção & controle , Animais , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos da radiação , Cognição/efeitos da radiação , Citocinas/genética , Citocinas/metabolismo , Giro Denteado/patologia , Giro Denteado/efeitos da radiação , Masculino , Aprendizagem em Labirinto , Ratos Sprague-Dawley , Memória Espacial/efeitos da radiação , Sinaptofisina/metabolismo
6.
Radiother Oncol ; 109(1): 71-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24060171

RESUMO

PURPOSE: Efficient tumor volume delineation by the combined use of PET/CT scanning is necessary for the proper treatment of non-small cell lung cancer (NSCLC). To understand the effect of variation in background intensity on PET-based gross tumor volume (GTV) delineation, we determined the background standard uptake values (SUVs) in normal lung, aorta (blood pool), and liver tissues and determined GTVs using different methods. METHODS: Thirty-seven previously untreated patients with pathologically confirmed NSCLC underwent PET/CT scanning with (18)F-fluorodeoxyglucose ((18)F-FDG). To obtain (18)F-FDG uptake values in normal tissues, regions of interest in the lung lobes (left upper, left lower, right upper, right middle, and right lower), aorta, and liver zones (left, intermediate, and right) were measured. The coefficient of variation (CV) of the SUV was measured for each normal structure. The CT-based GTV (GTV(CT)) was considered as the standard to which all PET-based GTVs were compared, and the correlation coefficient was analyzed to compare GTV obtained by the various delineation methods. Linear and logarithmic regression analyses were used to determine the relationship between GTV(CT) and GTV(PET). RESULTS: Normal lung tissue showed a significantly lower SUV and less stability than tissue of the aorta or liver. For the lung, aorta, and liver, the maximum SUV (SUV(max)) was 0.82 ± 0.32, 2.35 ± 0.37, and 3.24 ± 0.50 (CV: 38.79%, 15.82%, and 15.30%) and average SUV (SUV(ave)) was 0.49 ± 0.18, 1.68 ± 0.32, and 2.34 ± 0.36 (CV: 36.38%, 18.92%, and 15.44%), respectively. The SUVs of the lung varied from lobe to lobe. The GTV delineation method using the SUV(ave) of the lung lobe in which the tumor was found as background in the source-to-background ratio (SBR) method showed the best correlation with the volume of CT-based GTV (r=0.81). CONCLUSIONS: Our results show vast variation in the SUV among normal tissues, as well as in the different lung lobes. The tumor volume delineated using the SBR method correlated well with the CT-based tumor volume. We conclude that it is reasonable and precise to contour GTV in patients with NSCLC after taking into account the background intensity of the lung lobe in which the tumor is found.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Tomografia por Emissão de Pósitrons/métodos , Carga Tumoral , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Feminino , Fluordesoxiglucose F18 , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
7.
Zhonghua Nan Ke Xue ; 17(9): 794-8, 2011 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-21961239

RESUMO

OBJECTIVE: To observe the therapeutic effect of local antibiotic injection into the female prostate on female urethral syndrome (FUS), and search for an effective treatment for this disease. METHODS: This study included 163 FUS patients treated in the out-patient department between July 2009 and December 2010. According to the visiting order, the patients were randomly assigned to Groups A (n = 58), B (n = 55) and C (n = 50). All underwent routine treatment. Inaddition Group A received local injection of 2 ml of 80 000 U gentamycin + 2 ml of lidocaine, and Group B 2 ml of normal saline + 2 ml of lidocaine, both injected into the distal segment of the urethral back wall where the female prostate is located, twice a week for 3 weeks. The therapeutic effects were evaluated according to the changes of the patients' independent symptom scores at 2 and 4 weeks after the treatment. Disappearance of the symptoms was considered as "curative" , > 1/2 reduction in the symptom score as "obviously effective", 1/2 - > 1/4 reduction in the symptom score as "effective", and < 1/4 reduction or increase in the symptom score as "ineffective". RESULTS: At 2 weeks after the treatment, the total effectiveness rate was significantly higher in Group A (77.5%) than in B (67.3%) and C (68.0%) (P < 0.05), but with no statistically significant difference between B and C (P > 0.05). At 4 weeks, the total effectiveness rate of Group A was slightly decreased, but still remarkably higher than that of group B or C (P < 0.05). CONCLUSION: Local injection of gentamycin into the female prostate is effective for the treatment of female urethral syndrome.


Assuntos
Gentamicinas/uso terapêutico , Doenças Uretrais/tratamento farmacológico , Administração Tópica , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Gentamicinas/administração & dosagem , Humanos , Injeções , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
8.
Artigo em Chinês | MEDLINE | ID: mdl-19351467

RESUMO

OBJECTIVE: To investigate the relationship between gene polymorphism of CYP2E1, CYP1A1, IL-4 and susceptibility of medicamentosa-like dermatitis induced by trichloroethylene (TCE). METHODS: 35 patients with medicamentosa-like dermatitis induced by TCE were chosen as the patient group, and 35 healthy workers as control group. The real-time quantitative polymerase chain reaction (PCR) with TaqMan minor groove binding (MGB) probes was used to test single nucleotide polymorphisms (SNP) of CYP2E1, CYP1A1 and IL-4 in the patients with medicamentosa-like dermatitis as well as in the control. The genotypes and the frequency of genotype or allele were compared between the patients and control with statistical analysis. RESULTS: The frequency of allele G within CYP1A1 gene (rs1048943) was significantly higher in TCE patients (37.1%) than that in control (P<0.05); the frequency of allele T within CYP2E1-1053 C/T was significantly higher in TCE patients (41.4%) than that in control (P<0.01); the frequency of T/T within IL-4-588 C/T (rs2243250) was significantly higher in TCE patients (75.0%) than that in control (P<0.01), and the frequency of allele T within IL-4-588 C/T (rs2243250) was also significantly higher in TCE patients (87.5%) than that in control (P<0.01). CONCLUSION: The gene polymorphism of CYP2E1, CYP1A1, IL-4 is probably associated with hypersensitivity for the TCE patients with medicamentosa-like dermatitis, and could be one of the genetic factors related to the individual susceptibility to TCE exposure.


Assuntos
Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP2E1/genética , Dermatite Ocupacional/genética , Interleucina-4/genética , Tricloroetileno/efeitos adversos , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...