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Classical and quantum space-to-ground communications necessitate highly sensitive receivers capable of extracting information from modulated photons to extend the communication distance from near-earth orbits to deep space explorations. To achieve gigabit data rates while mitigating strong background noise photons and beam drift in a highly attenuated free-space channel, a comprehensive design of a multi-functional detector is indispensable. In this study, we present an innovative compact multi-pixel superconducting nanowire single-photon detector array that integrates near-unity detection efficiency (91.6%), high photon counting rate (1.61 Gcps), large dynamic range for resolving different photon numbers (1-24), and four-quadrant position sensing function all within one device. Furthermore, we have constructed a communication testbed to validate the advantages offered by such an architecture. Through 8-PPM (pulse position modulation) format communication experiments, we have achieved an impressive maximum data rate of 1.5 Gbps, demonstrating sensitivities surpassing previous benchmarks at respective speeds. By incorporating photon number information into error correction codes, the receiver can tolerate maximum background noise levels equivalent to 0.8 photons/slot at a data rate of 120 Mbps-showcasing a great potential for daylight operation scenarios. Additionally, preliminary beam tracking tests were conducted through open-loop scanning techniques, which revealed clear quantitative dependence indicating sensitivity variations based on beam location. Based on the device characterizations and communication results, we anticipate that this device architecture, along with its corresponding signal processing and coding techniques, will be applicable in future space-to-ground communication tasks.
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We propose a simulation method for a multireflector terahertz imaging system. The description and verification of the method are based on an existing active bifocal terahertz imaging system at 0.22 THz. Using the phase conversion factor and angular spectrum propagation, the computation of the incident and received fields requires only a simple matrix operation. The phase angle is used to calculate the ray tracking direction, and the total optical path is used to calculate the scattering field of defective foams. Compared with the measurements and simulations of aluminum disks and defective foams, the validity of the simulation method is confirmed in the field of view of 50â cm × 90â cm at 8 m. This work aims to develop better imaging systems by predicting their imaging behavior for different targets before manufacturing.
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N6-methyladenosine (m6A) plays a key role in many biological processes. However, the function and evolutionary relationship of m6A-related genes in insects remain largely unknown. Here we analysed the phylogeny of m6A-related genes among 207 insect species and found that m6A-related genes are evolutionarily conserved in insects. Subcellular localization experiments of m6A-related proteins in BmN cells confirmed that BmYTHDF3 was localized in the cytoplasm, BmMETTL3, BmMETTL14, and BmYTHDC were localized in the nucleus, and FL2D was localized to both the nucleus and cytoplasm. We examined the expression patterns of m6A-related genes during the embryonic development of Bombyx mori. To elucidate the function of BmMETTL3 during the embryonic stage, RNA sequencing was performed to measure changes in gene expression in silkworm eggs after BmMETTL3 knockdown, as well as in BmN cells overexpressing BmMETTL3. The global transcriptional pattern showed that knockdown of BmMETTL3 affected multiple cellular processes, including oxidoreductase activity, transcription regulator activity, and the cation binding. In addition, transcriptomic data revealed that many observed DEGs were associated with fundamental metabolic processes, including carbon metabolism, purine metabolism, amino acid biosynthesis, and the citrate cycle. Interestingly, we found that knockdown of BmMETTL3 significantly affected Wnt and Toll/Imd pathways in embryos. Taken together, these results suggest that BmMETTL3 plays an essential role in the embryonic development of B. mori, and deepen our understanding of the function of m6A-related genes in insects.
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Bombyx , Animais , Bombyx/genética , Bombyx/metabolismo , Metiltransferases/genética , Regulação da Expressão Gênica , Perfilação da Expressão Gênica , Transcriptoma , Desenvolvimento Embrionário/genéticaRESUMO
The imaginal disc growth factor (IDGF), belonging to the glycoside hydrolase 18 family, plays an important role in various physiological processes in insects. However, the detail physiological function of IDGF is still unclear. In this study, transcriptome analysis was performed on the fatbody isolated from staged control and BmIDGF mutant silkworm larvae. Transcriptional profiling revealed that the absence of BmIDGF significantly affected differentially expressed genes involved in tyrosine and purine metabolism, as well as multiple energy metabolism pathways, including glycolysis, galactose, starch, and sucrose metabolism. The interruption of BmIDGF caused similar and specific gene expression changes to male and female fatbody. Furthermore, a genome-scale metabolic network integrating metabolomic and transcriptomic datasets revealed 11 pathways significantly altered at the transcriptional and metabolic levels, including amino acid, carbohydrate, uric acid metabolism pathways, insect hormone biosynthesis, and ABC transporters. In conclusion, this multiomics analysis suggests that IDGF is involved in gene-metabolism interactions, revealing its unique role in melanin synthesis and energy metabolism. This study provides new insights into the physiological function of IDGF in insects.
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Bombyx , Masculino , Animais , Feminino , Bombyx/metabolismo , Melaninas/metabolismo , Discos Imaginais/metabolismo , Perfilação da Expressão Gênica , Metabolismo Energético , Peptídeos e Proteínas de Sinalização Intercelular/metabolismoRESUMO
Lipocalins exhibit functional diversity, including roles in retinol transport, invertebrate cryptic coloration, and stress response. However, genome-wide identification and characterization of lipocalin in the insect lineage have not been thoroughly explored. Here, we found that a lineage-specific expansion of the lipocalin genes in Lepidoptera occurred in large part due to tandem duplication events and several lipocalin genes involving insect coloration were expanded more via tandem duplication in butterflies. A comparative analysis of conserved motifs showed both conservation and divergence of lepidopteran lipocalin family protein structures during evolution. We observe dynamic changes in tissue expression preference of paralogs in Bombyx mori, suggesting differential contribution of paralogs to specific organ functions during evolution. Subcellular localization experiments revealed that lipocalins localize to the cytoplasm, nuclear membrane, or nucleus in BmN cells. Moreover, several lipocalin genes exhibited divergent responses to abiotic and biotic stresses, and 1 lipocalin gene was upregulated by 300 fold in B. mori. These results suggest that lipocalins act as signaling components in defense responses by mediating crosstalk between abiotic and biotic stress responses. This study deepens our understanding of the comprehensive characteristics of lipocalins in insects.
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Bombyx , Borboletas , Lepidópteros , Animais , Lepidópteros/genética , Bombyx/genética , Borboletas/genética , Lipocalinas/genética , Genoma de Inseto , Família Multigênica , FilogeniaRESUMO
The complex stripes and patterns of insects play key roles in behavior and ecology. However, the fine-scale regulation mechanisms underlying pigment formation and morphological divergence remain largely unelucidated. Here we demonstrated that imaginal disc growth factor (IDGF) maintains cuticle structure and controls melanization in spot pattern formation of Bombyx mori. Moreover, our knockout experiments showed that IDGF is suggested to impact the expression levels of the ecdysone inducible transcription factor E75A and pleiotropic factors apt-like and Toll8/spz3, to further control the melanin metabolism. Furthermore, the untargeted metabolomics analyses revealed that BmIDGF significantly affected critical metabolites involved in phenylalanine, beta-alanine, purine, and tyrosine metabolism pathways. Our findings highlighted not only the universal function of IDGF to the maintenance of normal cuticle structure but also an underexplored space in the gene function affecting melanin formation. Therefore, this study furthers our understanding of insect pigment metabolism and melanin pattern polymorphisms.
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Bombyx/fisiologia , Proteínas de Insetos/metabolismo , Melaninas/metabolismo , Pigmentação/fisiologia , Animais , Bombyx/anatomia & histologia , Sistemas CRISPR-Cas , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Proteínas de Insetos/genética , Larva/genética , Larva/fisiologia , Melaninas/biossíntese , Melaninas/genética , Metabolômica/métodos , Mutação , Filogenia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
In this study, we aimed to identify the tumor suppressive roles of zinc finger of the cerebellum 1 (ZIC1) in patients with malignant breast neoplasms and to examine the association between ZIC1 and survivin expression. For this purpose, 140 invasive breast cancer specimens, 1,075 RNA breast cancer samples from The Cancer Genome Atlas (TCGA), 6 human breast cancer cell lines and MCF-10A normal breast epithelial cells were selected in order to compare the expression level of ZIC1 with that of survivin via immunohistochemistry and western blot analysis. Subsequently, the MDA-MB-231 and SK-BR3 cells with a lower ZIC1 expression were transfected with rLV-Zic1-PGK-Puro lentivirus or rLV-ZsGreen-PGKPuro lentivirus in order to observe any alterations in cell proliferation and apoptosis through MTT assay, colony formation assay, mitochondrial membrane potential assay and flow cytometric analysis, and to analyze the modulation of molecular mechanisms by western blot analysis. In addition, xenograft mouse models were constructed to explore the role of ZIC1 in the growth of implanted tumors. The results revealed that ZIC1 negatively correlated with survivin in tumors and cells, and a higher ZIC1 RNA expression indicated a better overall survival in the 1,075 TCGA RNA breast cancer samples. In vitro, the overexpression of ZIC1 inhibited cell proliferation, reduced mitochondrial membrane potential and promoted the apoptosis of the MDA-MB-231 and SK-BR3 breast cancer cells by inactivating the Akt/mTOR/P70S6K pathway, suppressing survivin expression, modulating the cell cycle, releasing cytochrome c (Cyto-c) into the cytosol and activating caspase proteins. In vivo, an elevated ZIC1 expression suppressed the growth of implanted tumors and downregulated survivin expression in tumors. On the whole, the findings of this study demonstrate that ZIC1 plays a tumor suppressive role in breast cancer, by targeting surviving, significantly downregulating its expression.
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Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Inibidoras de Apoptose/genética , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adulto , Animais , Apoptose/genética , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo , Feminino , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Mastectomia , Potencial da Membrana Mitocondrial/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Transdução de Sinais/genética , Survivina , Proteínas Supressoras de Tumor/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
In Zhangbei County, Hebei Province, poplar-dominated shelterbelts are degraded to different extents. Water availability is the main limiting factor for plant survival in arid areas. The purpose of this study was to reveal the relationship between water availability and poplar degradation. Based on the hydrogen and oxygen stable isotope techniques, we explored the water sources of Populus simonii under different degradation degrees by comparing the isotopic values of P. simonii xylem water with that in potential water source, and calculated the utilization ratio of each water source. The results showed that the water sources of poplar trees varied with degradation degree. The water sources of P. simonii gradually transferred from the deep layer to the surface layer with the increases of degradation. P. simonii with no degradation mainly absorbed soil water in the range of 320-400 cm, with the utilization rate being 25.1%. P. simonii with slight degradation mainly used soil water at depth of 120-180, 180-240 and 240-320 cm. The total utilization rate of three layers was close to 50.0%, with less utilization of water from other layers. The moderately degraded P. simonii mainly used soil water at depth of 20-40, 40-60 and 60-80 cm. The utilization rate of each layer was 17.5%-20.9%, and the contribution rate of soil water under 120 cm was less than 10.0%. The severely degraded P. simonii mainly used water from surface soil layer (0-20 cm), with the utilization rate being 30.4%, which was significantly higher than that of other water sources. The water sources of poplar shelter forests were gradually shallower during the process of degradation. However, the low soil water content in the shallow layer could not meet the normal water demand of poplar, which would accelerate the degradation and even decline of poplar.
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Populus , Água , China , Florestas , Solo/químicaRESUMO
PURPOSE: Five members of the zinc finger of the cerebellum (ZIC) family-ZIC1, ZIC2, ZIC3, ZIC4, and ZIC5-have been shown to be involved in various carcinomas. Here, we aimed to explore the clinicopathologic and prognostic roles of ZIC family members in invasive breast cancer patients using immunohistochemical analysis, western blotting analysis, and real-time quantitative polymerase chain reaction (RT-qPCR). METHODS: A total of 241 female invasive breast cancer patients who underwent radical mastectomy between 2009 and 2011 were enrolled. ZIC proteins in 241 pairs of breast tumors and corresponding normal tissues were investigated using immunohistochemistry and the clinicopathologic roles of proteins were analyzed using Pearson's chi-square test. Kaplan-Meier curves and Cox regression analysis were also used to analyze the prognostic value of the ZIC proteins. In addition, 12 pairs of fresh-frozen breast tumors and matched normal tissues were used in the western blotting analysis and RT-qPCR. RESULTS: Only ZIC1 expression in normal tissues was obviously higher than that in tumors (p<0.001). On multivariate analysis, ZIC1 expression (in overall survival analysis: hazard ratio [HR], 0.405, 95% confidence interval [CI], 0.233-0.702, p=0.001; in disease-free survival analysis: HR, 0.395, 95% CI, 0.234-0.669, p=0.001) was identified as a prognostic indicator of invasive breast cancer. CONCLUSION: ZIC1, but not the other proteins, was obviously decreased in breast tumors and associated with clinicopathologic factors. Thus, ZIC1 might be a novel indicator to predict the overall and disease-free survival of invasive breast cancer patients.
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Nematic order often breaks the tetragonal symmetry of iron-based superconductors. It arises from regular structural transition or electronic instability in the normal phase. Here, we report the observation of a nematic superconducting state, by measuring the angular dependence of the in-plane and out-of-plane magnetoresistivity of Ba0.5K0.5Fe2As2 single crystals. We find large twofold oscillations in the vicinity of the superconducting transition, when the direction of applied magnetic field is rotated within the basal plane. To avoid the influences from sample geometry or current flow direction, the sample was designed as Corbino-shape for in-plane and mesa-shape for out-of-plane measurements. Theoretical analysis shows that the nematic superconductivity arises from the weak mixture of the quasi-degenerate s-wave and d-wave components of the superconducting condensate, most probably induced by a weak anisotropy of stresses inherent to single crystals.
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OBJECTIVE: There is a heated debate on whether the prognostic value of NME1 is favorable or unfavorable. Thus, we carried out a meta-analysis to evaluate the relationship between NME1 expression and the prognosis of patients with digestive system neoplasms. METHODS: We searched PubMed, EMBASE and Web of Science for relevant articles. The pooled odd ratios (ORs) and corresponding 95%CI were calculated to evaluate the prognostic value of NME1 expression in patients with digestive system neoplasms, and the association between NME1 expression and clinicopathological factors. We also performed subgroup analyses to find out the source of heterogeneity. RESULTS: 2904 patients were pooled from 28 available studies in total. Neither the incorporative OR combined by 17 studies with overall survival (OR = 0.65, 95%CI:0.41-1.03, P = 0.07) nor the pooled OR with disease-free survival (OR = 0.75, 95%CI:0.17-3.36, P = 0.71) in statistics showed any significance. Although we couldn't find any significance in TNM stage (OR = 0.78, 95%CI:0.44-1.36, P = 0.38), elevated NME1 expression was related to well tumor differentiation (OR = 0.59, 95%CI:0.47-0.73, P<0.00001), negative N status (OR = 0.54, 95%CI:0.36-0.82, P = 0.003) and Dukes' stage (OR = 0.43, 95%CI:0.24-0.77, P = 0.004). And in the subgroup analyses, we only find the "years" which might be the source of heterogeneity of overall survival in gastric cancer. CONCLUSIONS: The results showed that statistically significant association was found between NME1 expression and the tumor differentiation, N status and Dukes' stage of patients with digestive system cancers, while no significance was found in overall survival, disease-free survival and TNM stage. More and further researches should be conducted to reveal the prognostic value of NME1.
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Biomarcadores Tumorais/metabolismo , Neoplasias do Sistema Digestório/patologia , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Biomarcadores Tumorais/genética , Neoplasias do Sistema Digestório/genética , Neoplasias do Sistema Digestório/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , PrognósticoRESUMO
OBJECTIVE: There is a heated debate on whether the prognostic value of SPARC is favorable or unfavorable. Thus, we carried out a meta-analysis evaluating the relationship between SPARC expression and the prognosis of patients with pancreatic cancer. METHODS: We searched PubMed, EMBASE and Web of Science for relevant articles. The pooled hazard ratios (HRs) and corresponding 95%CI of overall survival (OS) were calculated to evaluate the prognostic value of SPARC expression in patients with pancreatic cancer. We also performed subgroup analyses. RESULTS: With 1623 patients pooled from 10 available studies, the incorporative HR showed an unfavorable prognosis of patients with pancreatic cancer in the multivariate analysis (HR = 1.55, 95%CI: 1.11-2.17, P = 0.01), but not in univariate analysis (HR = 1.41, 95%CI: 0.47-4.21, P = 0.54) and estimate (HR = 1.24, 95%CI: 0.72-2.13, P = 0.44). And this adverse impact could also be found in the subgroup analyses in multivariate analysis, especially in the stroma (HR = 1.53, 95%CI: 1.05-2.24, P = 0.03). However, the combined HR had the highly significant heterogeneity. No obvious publication bias was found. CONCLUSIONS: SPARC might be an unfavorable indicator in patients with pancreatic cancer, especially in the stroma. More and further researches should be conducted to reveal the prognostic value of SPARC.
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Osteonectina/análise , Pâncreas/patologia , Neoplasias Pancreáticas/diagnóstico , Biomarcadores Tumorais/análise , Humanos , Neoplasias Pancreáticas/patologia , Prognóstico , Modelos de Riscos Proporcionais , Análise de SobrevidaRESUMO
Developmental switching from growth to metamorphosis in imaginal primordia is an essential process of adult body planning in holometabolous insects. Although it is disciplined by a sequential action of the ecdysteroid, molecular mechanisms linking to cell proliferation are poorly understood. In the present study, we investigated the expression control of cell cycle-related genes by the ecdysteroid using the wing disc of the final-instar larvae of the silkworm, Bombyx mori. We found that the expression level of c-myc was remarkably elevated in the post-feeding cell proliferation phase, which coincided with a small increase in ecdysteroid titer. An in vitro wing disc culture showed that supplementation of the moderate level of the ecdysteroid upregulated c-myc expression within an hour and subsequently increased the expression of cell cycle core regulators, including A-, B-, D-, and E-type cyclin genes, Cdc25 and E2F1. We demonstrated that c-myc upregulation by the ecdysteroid was not inhibited in the presence of a protein synthesis inhibitor, suggesting a possibility that the ecdysteroid directly stimulates c-myc expression. Finally, results from the administration of a c-Myc inhibitor demonstrated that c-Myc plays an essential role in 20E-inducible cell proliferation. These findings suggested a novel pathway for ecdysteroid-inducible cell proliferation in insects, and it is likely to be conserved between insects and mammals in terms of steroid hormone regulation.
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Bombyx/crescimento & desenvolvimento , Ciclo Celular/fisiologia , Ecdisteroides/fisiologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Asas de Animais/crescimento & desenvolvimento , Animais , Proteínas de Ciclo Celular/genética , Proliferação de Células , Regulação da Expressão Gênica no Desenvolvimento , Larva/crescimento & desenvolvimentoRESUMO
The determination of the pairing symmetry is one of the most crucial issues for the iron-based superconductors, for which various scenarios are discussed controversially. Non-magnetic impurity substitution is one of the most promising approaches to address the issue, because the pair-breaking mechanism from the non-magnetic impurities should be different for various models. Previous substitution experiments demonstrated that the non-magnetic zinc can suppress the superconductivity of various iron-based superconductors. Here we demonstrate the local destruction of superconductivity by non-magnetic zinc impurities in Ba0.5K0.5Fe2As2 by exploring phase-slip phenomena in a mesoscopic structure with 119 × 102 nm(2) cross-section. The impurities suppress superconductivity in a three-dimensional 'Swiss cheese'-like pattern with in-plane and out-of-plane characteristic lengths slightly below â¼1.34 nm. This causes the superconducting order parameter to vary along abundant narrow channels with effective cross-section of a few square nanometres. The local destruction of superconductivity can be related to Cooper pair breaking by non-magnetic impurities.
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To understand the transcriptional regulation of E74B by low concentrations of ecdysone, the promoter activity of Bombyx mori E74B was assessed in the B. mori wing disc using a transient reporter assay. We identified the transcription start sites of BmE74B and found that the core promoter region consists of initiator (Inr) and downstream promoter elements (DPE). The 3.6-kb upstream promoter region of BmE74B was responsive to 20-hydroxyecdysone (20E) in a dose-dependent manner, and the highest luciferase activity was observed in the presence of 0.2 µg/ml 20E. Moreover, the upstream BmE74B promoter activity was induced by 20E in a stage-specific and time-dependent manner, and the 3.6-kb promoter contained essential elements for the temporal regulation of BmE74B. Furthermore, we found a set of putative ecdysone response elements (EcREs). Five of these elements are highly conserved, capable of binding to the ecdysone receptor. Mutation of more than three putative EcREs, followed by introduction into the wing discs, abolished the activation of the BmE74B promoter by a low concentration of ecdysone. The results confirmed the role of ecdysone response elements in the transcription regulation of BmE74B and demonstrated that multiple putative EcREs were involved in the maximum response of BmE74B to low concentrations of ecdysone.
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Ecdisona/metabolismo , Proteínas de Insetos/genética , Regiões Promotoras Genéticas , Asas de Animais/fisiologia , Animais , Bombyx/genética , Relação Dose-Resposta a Droga , Ecdisona/farmacologia , Ecdisterona/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Proteínas de Insetos/metabolismo , Dados de Sequência Molecular , Mutação , Receptores de Esteroides/metabolismo , Elementos de Resposta/efeitos dos fármacos , Sítio de Iniciação de Transcrição , Asas de Animais/efeitos dos fármacosRESUMO
OBJECTIVE: To establish the experimental autoimmune Lewis rat model of myasthenia gravis (EAMG) specific for muscle-specific kinase (MuSK). METHODS: Lewis rats were immunized subcutaneously with a single injection of 200 µl of MuSK (50/100 µg) emulsified in complete Freund's adjuvant (CFA). And MuSK was expressed according to the murine gene of MuSK (AY360453). Control rats were immunized with CFA alone. All rats were observed every other day in a blinded fashion for fatigue characteristics. The clinical symptoms were graded between 0 and 3. And the clinical scores were recorded. The serum levels of anti-MuSK IgG at Days 7 and 57 were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: The clinical symptoms of myasthenia gravis (MG) appeared at Day 16 and peaked at Days 18-22. The serum levels of anti-MuSK IgG were markedly elevated in the experimental groups compared with the control group. CONCLUSION: EAMG induced by MuSK is successfully established in rats. And this animal model may help us elucidate the pathogenesis of anti-MuSK myasthenia (AMM) and discover new drug therapy in the future.
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Autoanticorpos/imunologia , Modelos Animais de Doenças , Miastenia Gravis Autoimune Experimental , Receptores Proteína Tirosina Quinases/imunologia , Receptores Colinérgicos/imunologia , Animais , Feminino , Ratos , Ratos Endogâmicos LewRESUMO
Through BLAST search of the genomic database of Bombyx mori, we found a clone, BmorCPG11, which has only putative BR-C binding sites in the 2 kb upstream region. Both BmorCPG11 and BR-Z2 were expressed in the cephalic region of the epidermis, differently from BR-Z1 and BR-Z4. BR-Z2 transcripts increased by the addition of 20-hydroxyl-ecdysone (20E), which was slightly inhibited by cycloheximide. BmorCPG11 expression was also induced by the addition of 20E, which was inhibited by cycloheximide. Both BmorCPG11 and BR-Z2 were induced by the 20E pulse treatment, but they were inhibited by the addition of cycloheximide. Both genes showed similar expression pattern in wing discs during the developmental stage and in vitro ecdysone responsiveness, and both showed relatedness. The result of a reporter assay demonstrated the strong relatedness of BmorCPG11 and BR-Z2. The expression profiles of BmorCPG11 and BR-Z2 are different from those of BMWCP5 and ßFTZ-F1. The present findings showed different regulation of cuticular protein genes by ecdysone-responsive transcription factors at the pre-pupal stage of wing discs of B. mori.
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Bombyx/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Insetos/genética , Animais , Sítios de Ligação , Bombyx/genética , Proteínas de Insetos/metabolismo , Pupa/crescimento & desenvolvimento , Pupa/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Asas de Animais/crescimento & desenvolvimento , Asas de Animais/fisiologiaRESUMO
Single-crystal Ca(10)(Pt(4)As(8))(Fe(1.8)Pt(0.2)As(2))(5) superconducting (SC) nanowhiskers with widths down to hundreds of nanometers were successfully grown in a Ta capsule in an evacuated quartz tube by a flux method. Magnetic and electrical properties measurements demonstrate that the whiskers have excellent crystallinity with critical temperature of up to 33 K, upper critical field of 52.8 T, and critical current density of J(c) of 6.0 × 10(5) A/cm(2) (at 26 K). Since cuprate high-T(c) SC whiskers are fragile ceramics, the present intermetallic SC whiskers with high T(c) have better opportunities for device applications. Moreover, although the growth mechanism is not understood well, the technique can be potentially useful for growth of other whiskers containing toxic elements.
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The trimolter mutants of Bombyx mori have four instead of five larval instars of normal tetramolters. Here, we show that the tetramolter was induced in the recessive trimolter European No.7 mutant (rt-E7) by application of either the juvenile hormone analog (JHA) or 20-hydroxyecdysone (20E). However, treatments with JHA or 20E did not change the number of larval instars of the dominant trimolter Si Chuan mutant (DT-SC). Krüppel-homolog 1 (Kr-h1) is an early JH-response gene that mediates the anti-metamorphic action of JH. In the wing disc of tetramolter B. mori, Kr-h1 RNAs decreased shortly after ecdysis to the fifth instar, while pupal specifier gene, Broad Complex Z1 (BR-Z1) RNAs slightly increased and coincided with the onset of metamorphic competence of wing discs. Analysis of the developmental profile of Kr-h1 in the wing disc of rt-E7 showed that its transcript slightly increased from 12 to 24 h and gradually decreased between 24 and 72 h in the fourth (last) larval instar, while Kr-h1 mRNA decreased rapidly between 12 and 72 h in DT-SC. In addition, the expression of BR-Z1 in DT-SC during the early fourth (last) larval instar is relatively higher than that in rt-E7. These results indicated that the occurrence of pupal commitment of the wing disc in DT-SC was much earlier than that in rt-E7. In the early fourth larval instar of rt-E7, feeding on 20E or treatments with exogenous JHA caused up-regulation of Kr-h1, suppressed premature induction of BR-Z1, and then induced an additional larval instar. By contrast, in DT-SC mutant, since pupal commitment immediately occurred after third ecdysis, precocious metamorphosis was not successfully rescued. The results suggest that Kr-h1 and BR-Z1 involved in the prevention of precocious metamorphosis in recessive trimolter mutants by application of 20E and JHA. The result indicated that Kr-h1 and BR-Z1 expression reflected larval-pupal transition of the recessive trimolter of B. mori.
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Bombyx/fisiologia , Discos Imaginais/metabolismo , Proteínas de Insetos/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Metamorfose Biológica , Animais , Ecdisterona , MetopreneRESUMO
Aquaporin 4(AQP4) is a water channel protein strongly expressed in the central nervous system in perimicrovessel astrocyte foot processes, the glia limitans, and ependyma. Expression of AQP4 is highest at the blood-brain barrier and blood-spinal cord barrier, supporting its critical function in material transport across these structures. Recently, presence of the anti-aquaporin-4 antibody in sera has been used as an important diagnostic tool for neuromyelitis optica, suggesting a potential role in central nervous system inflammation. The aim of the present study was to examine AQP4 protein expression in the cerebellum and spinal cord from rats with experimental autoimmune encephalomyelitis. By western blot analysis, AQP4 expression increased during experimental autoimmune encephalomyelitis development, and peaked at onset (lumbar enlargement) or climax (cerebellum) of neurological signs of experimental autoimmune encephalomyelitis. There was also a faster and more pronounced increase in permeability in the cerebellar blood-brain barrier and the lumbar enlargement blood-spinal cord barrier consistent with AQP4 expression, which was manifested by increased Evans Blue leakage and reduced tight junction protein expression. In conclusion, aquaporin upregulation may be involved in the development of inflammation in the acute phase of experimental autoimmune encephalomyelitis, and may correlate with damage to central nervous system barrier function.