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We have developed two series of amine-functionalized zirconium (Zr) metal-organic framework-808 (MOF-808), which were produced by postsynthetic modifications to have either amino acids coordinated to Zr ions (MOF-808-AAs) or polyamines covalently bound to the chloro-functionalized structure (MOF-808-PAs). These MOF variants were comprehensively characterized by liquid-state 1H nuclear magnetic resonance (NMR) measurements and potentiometric acid-base titration to determine the amounts of amines, energy-dispersive X-ray spectroscopy to assess the extent of covalent substitution by polyamines, powder X-ray diffraction analysis to verify the maintenance of the MOF crystallinity and structure after postsynthetic modifications, nitrogen sorption isotherm measurements to confirm retention of the porosity, and water sorption isotherm measurements to find the water uptake in the pores of each member of the series. Evaluation and testing of these compounds in direct air capture (DAC) of CO2 showed improved CO2 capture performance for the functionalized forms, especially under humid conditions: In dry conditions, the l-lysine- and tris(3-aminopropyl)amine-functionalized variants, termed as MOF-808-Lys and MOF-808-TAPA, exhibited the highest CO2 uptakes at 400 ppm, measuring 0.612 and 0.498 mmol g-1, and further capacity enhancement was achieved by introducing 50% relative humidity, resulting in remarkable uptakes of 1.205 and 0.872 mmol g-1 corresponding to 97 and 75% increase compared to the dry uptakes, respectively. The mechanism underlying the enhanced uptake efficiency was revealed by 13C solid-state NMR and temperature-programmed desorption measurements, indicating the formation of bicarbonate species, and therefore a stoichiometry of 1:1 CO2 to each amine site.
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Skin, characterized by its distinctive gradient structure and interwoven fibers, possesses remarkable mechanical properties and highly sensitive attributes, enabling it to detect an extensive range of stimuli. Inspired by these inherent qualities, a pioneering approach involving the crosslinking of macromolecules through in situ electron beam irradiation (EBI) is proposed to fabricate gradient ionogels. Such a design offers remarkable mechanical properties, including excellent tensile properties (>1000%), exceptional toughness (100 MJ m-3), fatigue resistance, a broad temperature range (-65-200°C), and a distinctive gradient modulus change. Moreover, the ionogel sensor exhibits an ultra-fast response time (60 ms) comparable to skin, an incredibly low detection limit (1 kPa), and an exceptionally wide detection range (1 kPa-1 MPa). The exceptional gradient ionogel material holds tremendous promise for applications in the field of smart sensors, presenting a distinct strategy for fabricating flexible gradient materials.
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The systematic treatment of colorectal cancer (CRC) still has room for improvement. The efficacy of chemotherapy, that of anti-vascular therapy, and that of immunotherapy have been unsatisfactory. In recent years, nanomaterials have been used as carriers to improve the bioavailability of anticancer drugs. For the treatment of colorectal cancer, nanodrugs increase the possibility of more precise targeted delivery. However, the actual benefits may cover more aspects. Nanocarriers can produce synergistic effects with anticancer drugs, including the scavenging of reactive oxygen species and co-delivery of a variety of drugs. Currently, immunotherapy has very limited clinical applications in CRC. Modified nanocarriers can activate the immune microenvironment, which can be used for staging antigen recognition or the immune response. Cancer vaccines based on nanomaterials and modified immune checkpoint inhibitors have shown therapeutic potential in animal models. Considering the direct or indirect relationship between the intestinal microflora and CRC, a variety of nanodrugs that regulate microbial function have been explored as an anticancer strategy, and the special structure of microorganisms can also be used as a basis for improving the delivery of traditional nanoparticles (NPs). This review summarizes recent research performed on nanocarriers in in vivo and in vitro models and the synergistic anticancer effects of nanocarriers, focusing on the interaction between NPs and the body, resulting in enhanced efficacy and immune activation. Furthermore, this review describes the current trend of NPs used in the treatment of CRC.
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Antineoplásicos , Neoplasias Colorretais , Nanopartículas , Animais , Nanomedicina , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Imunoterapia/métodos , Nanopartículas/química , Neoplasias Colorretais/tratamento farmacológico , Microambiente TumoralRESUMO
Perovskite-based photodetectors exhibit potential applications in communication, neuromorphic chips, and biomedical imaging due to their outstanding photoelectric properties and facile manufacturability. However, few of perovskite-based photodetectors focus on ultraviolet-visible-short-wavelength infrared (UV-Vis-SWIR) broadband photodetection because of the relatively large bandgap. Moreover, such broadband photodetectors with individual nanocrystal channel featuring monolithic integration with functional electronic/optical components have hardly been explored. Herein, an individual monocrystalline MAPbBr3 nanoplate-based photodetector is demonstrated that simultaneously achieves efficient UV-Vis-SWIR detection and fast-response. Nanoplate photodetectors (NPDs) are prepared by assembling single nanoplate on adjacent gold electrodes. NPDs exhibit high external quantum efficiency (EQE) and detectivity of 1200% and 5.37 × 1012 Jones, as well as fast response with rise time of 80 µs. Notably, NPDs simultaneously achieve high EQE and fast response, exceeding most perovskite devices with multi-nanocrystal channel. Benefiting from the high specific surface area of nanoplate with surface-trap-assisted absorption, NPDs achieve high performance in the near-infrared and SWIR spectral region of 850-1450 nm. Unencapsulated devices show outstanding UV-laser-irradiation endurance and decent periodicity and repeatability after 29-day-storage in atmospheric environment. Finally, imaging applications are demonstrated. This work verifies the potential of perovskite-based broadband photodetection, and stimulates the monolithic integration of various perovskite-based devices.
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We report the dispersive wave (DW) emission from the Gaussian pulse with temporal sinusoidal phase (TSP) modulation. The TSP-induced chirp can enhance or cancel the chirp generated by self-phase modulation by properly selecting the modulation parameters of TSP, which can influence the nonlinear propagation of the TSP-modulated pulse. It is shown that the TSP can effectively control the resonant frequency and energy conversion efficiency of the DW emission. We give a modified phase-matching condition to predict the resonant frequencies, which agree with the simulation results obtained by numerically solving the nonlinear Schrödinger equation. The enhanced conversion efficiency of the DWs can be increased up to 28% with only TSP modulation. Our results can extend the application of temporal phase modulation technology for wavelength conversion, and broadband supercontinuum generation.
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We investigate the dispersive waves (DWs) emitted from shaped pulses with spectral Heaviside step phases (HSPs). The spectrally HSP-modulated pulse exhibits a unique double-peak structure, where the intensity and separation of the twin peaks are determined by the modulation depth and frequency detuning. By tailoring the parameters of the HSP suitably, we can control the DW emission with regard to resonant frequency and conversion efficiency. As the intensity ratio or relative separation of neighboring peaks is elaborately chosen, the DW emission can be effectively boosted, or a solitonic cage can be constructed for realizing temporal reflections and refractions associated with spectral broadening and multi-peak spectra of the output DWs. These findings offer a straightforward and efficient approach for controlling the DW emission, which is highly relevant to the advancement of supercontinuum generation and wavelength conversion technology.
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In recent years, biomimetic polarization navigation has become a research hotspot in navigation fields because of its autonomy and concealment. Existing point-source polarization navigation sensors mainly use a logarithmic amplifier as the arithmetic unit to obtain polarization information. However, these sensors suffer from zero drift and low detection accuracy, which limits their application range. To address the above issues, a polarization navigation sensor based on a differential amplifier is designed as the operational unit. Based on the change of the arithmetic unit of the polarization signal, the algorithm for calculating the heading angle of the sensor is improved. The results of the orientation experiments with the designed sensor in clear weather indicate that the orientation error is ±1.243∘, and the standard deviation is 0.351°. The polarization navigation sensor can extract polarized light information and calculate the heading without accumulation of errors over time accurately and achieves good real-time performance.
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The burgeoning complexity of space missions has amplified the research focus on robots that are capable of assisting astronauts in accomplishing tasks within space stations. Nevertheless, these robots grapple with substantial mobility challenges in a weightless environment. This study proposed an omnidirectional continuous movement method for a dual-arm robot, inspired by the movement patterns of astronauts within space stations. On the basis of determining the configuration of the dual-arm robot, the kinematics and dynamics model of the robot during contact and flight phases were established. Thereafter, several constraints are determined, including obstacle constraints, prohibited contact area constraints, and performance constraints. An optimization algorithm based on the artificial bee colony algorithm was proposed to optimize the trunk motion law, contact point positions between the manipulators and the inner wall, as well as the driving torques. Through the real-time control of the two manipulators, the robot is capable of achieving omnidirectional continuous movement across various inner walls with complex structures while maintaining optimal comprehensive performance. Simulation results demonstrate the correctness of this method. The method proposed in this paper provides a theoretical basis for the application of mobile robots within space stations.
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Robótica , Robótica/métodos , Movimento (Física) , Algoritmos , Simulação por Computador , Fenômenos BiomecânicosRESUMO
A polarized light sensor is applied to the front-end detection of a biomimetic polarized light navigation system, which is an important part of analyzing the atmospheric polarization mode and realizing biomimetic polarized light navigation, having received extensive attention in recent years. In this paper, biomimetic polarized light navigation in nature, the mechanism of polarized light navigation, point source sensor, imaging sensor, and a sensor based on micro nano machining technology are compared and analyzed, which provides a basis for the optimal selection of different polarized light sensors. The comparison results show that the point source sensor can be divided into basic point source sensor with simple structure and a point source sensor applied to integrated navigation. The imaging sensor can be divided into a simple time-sharing imaging sensor, a real-time amplitude splitting sensor that can detect images of multi-directional polarization angles, a real-time aperture splitting sensor that uses a light field camera, and a real-time focal plane light splitting sensor with high integration. In recent years, with the development of micro and nano machining technology, polarized light sensors are developing towards miniaturization and integration. In view of this, this paper also summarizes the latest progress of polarized light sensors based on micro and nano machining technology. Finally, this paper summarizes the possible future prospects and current challenges of polarized light sensor design, providing a reference for the feasibility selection of different polarized light sensors.
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Biomimética , Refração OcularRESUMO
Psychiatric symptoms are common risk factors of violent behaviors among psychiatric patients. This study explored the interrelationship between violence and psychiatric symptoms in male psychiatric inpatients. This is a cross-sectional survey conducted in 2019. All patients admitted to the Male Psychiatry Unit of the Second Xiangya Hospital were consecutively recruited. The presence of five violent behaviors and eleven psychiatric symptoms were collected by reviewing medical records and were included as categorical variable in the network analyses. A total of 673 participants were included. The most central symptoms were "flight of ideas", "property-oriented violence", "emotional high", "verbal violence", "physical violence attempt", and "physical violence" in the network of psychiatric symptoms and violent behaviors. The bridge symptoms connecting violence and psychiatric symptoms were "verbal violence", "property-oriented violence", "hyperbulia", and "emotional high" according to the indices of bridge expected influence. The directed acyclic graph analysis revealed that "emotional high" and "hyperbulia" were the key psychiatric symptoms triggering violence, while "verbal violence" and "property-oriented violence" were the most upstream violent behavior. Verbal and property-oriented violence should be addressed in the risk assessment among male psychiatric inpatients. In addition, emotional high and hyperbulia are the potential treatment targets for violent behaviors.
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Pacientes Internados , Transtornos Mentais , Humanos , Masculino , Pacientes Internados/psicologia , Estudos Transversais , Transtornos Mentais/psicologia , Agressão/psicologia , ViolênciaRESUMO
Research on facial micro-expression analysis has been going on for decades. Micro-expression can reflect the true emotions of individuals, and it has important application value in assisting auxiliary diagnosis and disease monitoring of mental disorders. In recent years, the development of artificial intelligence and big data technology has made the automatic recognition of micro-expressions possible, which will make micro-expression analysis more convenient and more widely used. This paper reviews the development of facial micro-expression analysis and its application in forensic psychiatry, to look into further application prospects and development direction.
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Psiquiatria Legal , Transtornos Mentais , Humanos , Inteligência Artificial , Transtornos Mentais/diagnóstico , Expressão Facial , EmoçõesRESUMO
We report the first covalent incorporation of reactive aliphatic amine species into covalent organic frameworks (COFs). This was achieved through the crystallization of an imine-linked COF, termed COF-609-Im, followed by conversion of its imine linkage to base-stable tetrahydroquinoline linkage through aza-Diels-Alder cycloaddition, and finally, the covalent incorporation of tris(3-aminopropyl)amine into the framework. The obtained COF-609 exhibits a 1360-fold increase in CO2 uptake capacity compared to the pristine framework and a further 29% enhancement in the presence of humidity. We confirmed the chemistry of framework conversion and corroborated the enhanced CO2 uptake phenomenon with and without humidity through isotope-labeled Fourier transform infrared spectroscopy and solid-state nuclear magnetic resonance spectroscopy. With this study, we established a new synthetic strategy to access a class of chemisorbents characterized by high affinity to CO2 in dilute sources, such as the air.
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Estruturas Metalorgânicas , Aminas , Dióxido de Carbono/química , Cristalização , Iminas/químicaRESUMO
OBJECTIVES: To understand the legal application and case deposition of assessment opinions of sexual self-defense capability, and to explore the necessity of legal correspondence in the sexual defense capability assessment. METHODS: According to the self-made questionnaire, the cases of sexual self-defense capability assessment completed by the Academy of Forensic Science from January 1, 2012 to December 31, 2018 were statistically analyzed through telephone interviews and referrals. RESULTS: Among the 69 cases, 3 cases (4.3%) had complete sexual self-defense capability, 30 cases (43.5%) had weakened sexual self-defense capability, 32 cases (46.2%) had no sexual self-defense capability, and 4 cases (5.8%) were not suitable for assessment. Among the 30 cases with weakened sexual self-defense ability, 15 cases were filed and investigated by public security authorities for rape and 15 cases were not. The inconsistent rate of disposition was 1â¶1. Among the 15 rape cases filed and investigated by the public security authorities, 10 cases were arrested and prosecuted by the procuratorate and sentenced to fixed-term imprisonment by the court, while the other 5 cases were not arrested and prosecuted by the procuratorate, with an inconsistent rate of disposition being 2â¶1. CONCLUSIONS: The legal application of the assessment opinion on the weakening of sexual self-defense capability is inconsistent, and the judicial disposition is confusing. It is imperative to unify and correspond the classification of sexual self-defense capability with the legal requirements.
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Estupro , Psiquiatria Legal , Medicina Legal , Ciências ForensesRESUMO
We investigate the process of dispersive waves (DWs) emitted from Gaussian pulse (GP) with an initial quadratic spectral phase (QSP). We show that the radiation of DWs is strongly affected by the QSP parameter. The conversion efficiency and resonant frequency of DWs are effectively enhanced and controlled by tuning the sign and magnitude of the initial QSP. At variance with the case of pure GP, the DWs emission is first advanced and then delayed for negatively QSP modulated GPs; while it is always delayed for positively QSP modulated GPs. We present a modified phase-matching formula that allows us to predict DWs spectral peaks. The resonant frequencies predicted by the phase-matching condition are in very good agreement with the results obtained from the numerical simulation based on the generalized nonlinear Schrödinger equation. The results presented here can be utilized as a effective tool to manipulate DWs emission for applications such as frequency conversion.
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We investigate both analytically and numerically the propagation dynamic of on-axis and off-axis cosine-Gaussian (CG) beams in a linear medium with quadratic external potential. CG beam propagation evolves periodically with a period depended on the potential depth (α) and whether the beam shape is symmetrical with respect to optical axis. In each period, the CG beam first splits into two sub-beams with different accelerated direction; they then reverse the accelerated direction owing to the quadratic external potential and finally merge again to reproduce its initial shape, and the whole process repeats periodically. The intensity oscillation period of the off-axis CG beam is double times than that of the on-axis one. At the special position, the beam (or spectral) shape is strongly related to the initial spectral (beam) shape. The corresponding scaled relationship is that the spatial intensity Ix (or spatial frequency axis k) is α times the spectral intensity Ik (or space axis x). The interaction of two spatially separated CG beams still exhibit periodic evolution with complex structure in the regime of focal point. The propagation dynamics of two-dimensional CG beams are also presented. When the propagation distance is exactly an integer multiple of half period, there are four focal points in the diagonal position.
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Developing an autonomous self-healing polyurethane (PU) elastomer with excellent mechanical properties and high ductility has attracted increasing attention. Nowadays, the synthesis of elastomers with excellent mechanical properties and rapid self-healing at room temperature faces a huge challenge. Herein, This work reports a new supramolecular PU with excellent mechanical properties and rapid self-healing at room temperature through the introduction of T-type chain extender into the supramolecular polymer chain. The introduction of T-chain extender can be used to enhance the mechanical strength of PU, and the multiple hydrogen bonds on the side-chain provide theoretical support for the rapid self-healing ability of PU. Maximum stress of the synthesized PU can reach 3.4 ± 0.15 Mpa, and maximum elongation at break can reach 3200% ± 160%. Due to flexibility and re-constructability of side-chain hydrogen bonds, PU stress repair efficiency can reach 96.7%, and can be self-healing scratches rapidly and effectively at room temperature. The mechanical properties and self-healing properties of PU can be adjusted by the content of T-type chain extender. The PU is applied to the metal surface coating, which has excellent acid-base resistance, bond strength up to 2.9 ± 0.1 Mpa, and the ability to eliminate local damage on the coating surface quickly at room temperature.
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Elastômeros , Poliuretanos , Ligação de Hidrogênio , Resistência à TraçãoRESUMO
BACKGROUND: Early childhood caries is an urgent public health concern. The aim of this study was to investigate salivary proteomic biomarkers for the surveillance of changes in the high-risk status of early childhood caries. The process involves the screening of specific salivary peptides that were differentially expressed only under dynamic changes in individual caries status. METHODS: Stimulated whole saliva samples were collected from 28 kindergarten children aged 3-4 years in Beijing at baseline and 3 months and 6 months after baseline. A total of 68 samples were collected. In terms of their caries status and progress during the observation period, participants were divided into 3 groups; 7 in the non-caries recurrence group, 6 in the caries recurrence group, and 15 in the healthy control group. Salivary peptides that exhibited no significant differences in cross-sectional comparisons between different groups of caries status but only expressed differentially along with dynamic changes of individual caries were screened using the technique of magnetic beads combined with matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). The technique of liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) was employed to identify the proteins from which these peptides were derived. RESULTS: We found two salivary peptides differentially expressed only under dynamic changes in individual caries status in the above comparisons; mass-to-charge ratio (m/z) values of the two peptides were 1045.9 and 2517.6, respectively (P < 0.05). Principal component analysis (PCA) and the decision tree model based on these two peptides showed an acceptable distinguishing ability for changes in the high-risk status of early childhood caries. The source proteins of the two peptides with m/z values of 1045.9 and 2517.6 were identified as submandibular gland androgen regulatory protein 3B (SMR-3B) and mucin-7, respectively. CONCLUSIONS: Two proteins in children's saliva, namely SMR-3B and mucin-7, have the potentiality to serve as candidate biomarkers for dynamic surveillance of changes in high-risk status of early childhood caries.
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Suscetibilidade à Cárie Dentária , Proteômica , Biomarcadores , Criança , Pré-Escolar , Estudos Transversais , Humanos , Saliva , Proteínas e Peptídeos Salivares , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em TandemRESUMO
OBJECTIVES: To understand the current status of appraisal of post-concussion syndrome disability and the reasons for the changes in re-appraisal opinions. METHODS: The cases that were judged as "post-concussion syndrome and ten-level disability" in the first appraisal and re-appraised for psychiatric impairment by the Academy of Forensic Science in 2019 were analyzed retrospectively. RESULTS: There were 75 cases, including 58 cases with pre-hospital emergency medical records, among which 39 cases were clearly recorded to be without a history of coma; 74 cases had emergency medical records, among which 44 cases were recorded of having a history of coma; 43 cases had follow-up medical records, among which 24 cases had a history of psychiatric follow-up. The most complained symptoms of the appraisee in appraisal and examination include headache, dizziness, poor sleep at night, irritability, memory loss, fatigue and inattention. The main reasons for the re-appraisal application include doubts about the history of coma, doubts about the credibility of mental symptoms, post-concussion syndrome didn't meet the disability criteria, and objections to the original appraisal procedure or the original appraisal agency. The appraisal opinions of a total of 47 cases were changed. Seven of them did not meet the disability criteria, and the main reason was that there was no clear history of coma and no head injury was admitted; the coma history of the 40 other cases had to be confirmed by the court before they can be clearly identified as disabilities. The reason was that the records about the history of coma were inconsistent or there were alterations and additional information. CONCLUSIONS: In the past, the conditions for appraisal of post-concussion syndrome disability were too lax and must be further standardized and strictly controlled.
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Concussão Encefálica , Traumatismos Craniocerebrais , Transtornos Mentais , Síndrome Pós-Concussão , Concussão Encefálica/complicações , Concussão Encefálica/diagnóstico , Cefaleia/psicologia , Humanos , Síndrome Pós-Concussão/diagnóstico , Síndrome Pós-Concussão/psicologia , Estudos RetrospectivosRESUMO
Odorant-binding proteins (OBPs) in insects are essential for mating and oviposition host selection. How these OBPs respond to different hosts at the mRNA level and their effects on behavior remain poorly characterized. The oriental fruit fly Bactrocera dorsalis is a highly invasive agricultural pest with an extremely broad host range and high fecundity. Based on our previously constructed B. dorsalis transcriptome, six OBPs that were differentially expressed during three different physiological adult stages were identified. A phylogenetic tree was constructed to illustrate the relationships of these six OBPs with OBP sequences from three other dipteran species (Drosophila melanogaster, Anopheles gambiae, and Ceratitis capitata). The spatiotemporal expression profiles of the six OBPs were analyzed using quantitative real-time PCR. Our results revealed that OBP19c, OBP44a, OBP99a, and OBP99d were abundantly expressed from the prepupa stage to the adult stage, and most of the OBPs were mainly expressed in the head, wings, and antennae. The expression levels of these OBPs were upregulated when female flies were exposed to their preferred hosts. Silencing OBP99a resulted fewer eggs being laid compared with the control group when the females were exposed to their preferred host, that is, banana, whereas more eggs were laid when a non-preferred host, that is, tomato, was used. Furthermore, silencing OBP99a led to sexually dimorphic mating behavior. dsOBP99a-injected males dramatically reduced courtship, whereas enhanced courtship was observed in the treated females. These data indicate that OBPs may participate in different biological processes of B. dorsalis. Our study will provide insight into the molecular mechanism of chemoreception and help develop ecologically friendly pest-control strategies.
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Proteínas de Insetos/metabolismo , Receptores Odorantes/metabolismo , Tephritidae/metabolismo , Animais , Corte , Feminino , Solanum lycopersicum , Masculino , Musa , Especificidade de Órgãos , Oviposição , Filogenia , Receptores Odorantes/genética , Comportamento Sexual Animal , Tephritidae/genéticaRESUMO
OBJECTIVE: To explore the correlation between the interleukin-17 (IL-17) level of peripheral blood and aggression of bipolar mania. METHODS: Thirty-six patients of bipolar mania were selected as experimental group by DSM-IV-TR and received treatment with quetiapine and lithium. Thirty-six healthy volunteers with similar age and gender were selected as control group. The level of IL-17 at baseline in each group and the level of IL-17 in the experimental group after treatment for 2, 4 and 8 weeks were detected by ELISA. RESULTS: The level of IL-17 in experimental group at baseline, after treatment for 2 and 4 weeks were all significantly higher than that in control group. After 8 weeks treatment, there was no significant difference between the two groups (P > 0.05). After 2, 4 and 8 weeks treatment, the total score and aggression score of Young Mania Rating Score (YMRS) were significantly lower than the baseline level (P < 0.05). In experimental group, the level of IL-17 was positively correlated with the two scores of YMRS at baseline (P < 0.05). CONCLUSION: Bipolar mania may be related to the up-regulation of IL-17. The level of IL-17 is related to the severity of manic symptoms at baseline, especially aggression symptom.