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1.
Pest Manag Sci ; 80(2): 744-755, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37779104

RESUMEN

BACKGROUND: Mythimna loreyi is an important agricultural pest with a sensitive sex pheromone communication system. To clarify the pheromone binding proteins (PBPs) and pheromone receptors (PRs) involved in sex pheromone perception is important for both understanding the molecular olfactory mechanism and developing a new pest control strategy in M. loreyi. RESULTS: First, the electroantennogram (EAG) assay showed that male M. loreyi displayed the highest response to the major sex pheromone component Z9-14:Ac, and higher responses to two minor components, Z7-12:Ac and Z11-16:Ac. Second, the fluorescence competition binding assay showed that PBP1 bound all three pheromones and other tested compounds with high or moderate affinity, while PBP2 and PBP3 each bound only one pheromone component and few other compounds. Third, functional study using the Xenopus oocyte system demonstrated that, of the six candidate PRs, PR2 was weakly sensitive to the major pheromone Z9-14:Ac, but was strongly sensitive to pheromone analog Z9-14:OH; PR3 was strongly and specifically sensitive to a minor component Z7-12:Ac; PR4 and OR33 were both weakly sensitive to another minor component, Z11-16:Ac. Finally, phylogenetic relationship and ligand profiles of PRs were compared among six species from two closely related genera Mythimna and Spodoptera, suggesting functional shifts of M. loreyi PRs toward Spodoptera PRs. CONCLUSION: Functional differentiations were revealed among three PBPs and six PRs in sex pheromone perception, laying an important basis for understanding the molecular mechanism of sex pheromone perception and for developing new control strategies in M. loreyi. © 2023 Society of Chemical Industry.


Asunto(s)
Mariposas Nocturnas , Atractivos Sexuales , Animales , Masculino , Atractivos Sexuales/farmacología , Atractivos Sexuales/metabolismo , Filogenia , Mariposas Nocturnas/metabolismo , Feromonas/metabolismo , Percepción
2.
J Agric Food Chem ; 71(51): 20602-20612, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38088835

RESUMEN

Ionotropic receptors (IRs) play an important role in olfaction, but little is known in nondrosophila insects. Here, we report in vitro and in vivo functional characterization of IR75q.2 in the invasive moth pest Spodoptera frugiperda. First, 13 IRs (including four coreceptor IRs) were found specifically or highly expressed in adult antennae. Second, these IRs were tested for responding profiles to 59 odorants using the Xenopus oocyte expression system, showing that only SfruIR75q.2 responded to 8-10C fatty acids and their corresponding aldehydes, with SfruIR8a as the only coreceptor. Third, the three acids (especially nonanoic acid) showed repellent effects on moth's behavior and oviposition, but the repellence significantly reduced to the insects with IR75q.2 knockout by CRISPR/Cas9. Taken together, our study reveals the function of SfruIR75q.2 in perception of acid and aldehyde odorants and provides the first in vivo evidence for olfactory function of an odor-specific IR in Lepidoptera.


Asunto(s)
Mariposas Nocturnas , Animales , Femenino , Spodoptera/fisiología , Mariposas Nocturnas/genética , Insectos , Ácidos Grasos/metabolismo , Larva
3.
Pestic Biochem Physiol ; 196: 105619, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37945255

RESUMEN

The insect olfaction plays crucial roles in many important behaviors, in which ORs are key determinants for signal transduction and the olfactory specificity. Spodoptera litura is a typical polyphagous pest, possessing a large repertoire of ORs tuning to broad range of plant odorants. However, the specific functions of those ORs remain mostly unknown. In this study, we functionally characterized one S. litura OR (OR51) that was highly expressed in the adult antennae. First, by using Xenopus oocyte expression and two-electrode voltage clamp recording system (XOE-TEVC), OR51 was found to be strongly and specifically responsive to vanillin (a volatile of S. litura host plants) among 77 tested odorants. Second, electroantennogram (EAG) and Y-tube behavioral experiment showed that vanillin elicited significant EAG response and attraction behavior especially of female adults. This female attraction was further confirmed by the oviposition experiment, in which the soybean plants treated with vanillin were significantly preferred by females for egg-laying. Third, 3D structural modelling and molecular docking were conducted to explore the interaction between OR51 and vanillin, which showed a high affinity (-4.46 kcal/mol) and three residues (Gln163, Phe164 and Ala305) forming hydrogen bonds with vanillin, supporting the specific binding of OR51 to vanillin. In addition, OR51 and its homologs from other seven noctuid species shared high amino acid identities (78-97%) and the same three hydrogen bond forming residues, suggesting a conserved function of the OR in these insects. Taken together, our study provides some new insights into the olfactory mechanisms of host plant finding and suggests potential applications of vanillin in S. litura control.


Asunto(s)
Receptores Odorantes , Animales , Femenino , Spodoptera/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Simulación del Acoplamiento Molecular , Plantas/química , Proteínas de Insectos/metabolismo
4.
J Agric Food Chem ; 71(37): 13795-13804, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37694971

RESUMEN

Moths rely on plant volatiles to locate appropriate plants for feeding and laying eggs. While extensive research has been conducted on the global agricultural pests, Spodoptera frugiperda and Spodoptera litura, their molecular mechanisms for detecting plant volatiles remain mostly unknown. Here, we have demonstrated that nonanal, a common plant volatile, is attractive for both virgin and gravid females of the two species. Second, we have identified a conserved odorant receptor clade (SfruOR47 clade) that is primarily tuned to nonanal. Finally, by three-dimensional (3D) structure prediction, molecular docking, and site-directed mutagenesis, we have revealed that the His57 and Glu61 residues, also shared by other six orthologous ORs, are essential for nonanal binding in SfruOR47 and SlituOR9, indicating the conserved structure and function of ORs in the SfruOR47 clade. These findings offer novel insights into the molecular mechanisms and evolutionary aspects of moth behavior in response to plant volatiles.


Asunto(s)
Receptores Odorantes , Femenino , Animales , Spodoptera/genética , Receptores Odorantes/genética , Simulación del Acoplamiento Molecular , Aldehídos
5.
Front Oncol ; 13: 1200203, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37207157

RESUMEN

Background: Endothelial cells (ECs) play a vital role in promoting the progression of malignant cells, and they exhibit heterogeneity in their phenotypic characteristics. We aimed to explore the initiating cells of ECs in osteosarcoma (OS) and investigate their potential interaction with malignant cells. Method: We obtained scRNA-seq data from 6 OS patients, and datasets were batch-corrected to minimize variations among samples. Pseudotime analysis was performed to investigate the origin of differentiation of ECs. CellChat was employed to examine the potential communication between endothelial cells and malignant cells, and gene regulatory network analysis was performed to identify transcription factor activity changes during the conversion process. Importantly, we generated TYROBP-positive ECs in vitro and investigated its role in OS cell lines. Finally, we explored the prognosis of specific ECs cluster and their impact on the tumor microenvironment (TME) at the bulk transcriptome level. Results: The results showed that TYROBP-positive ECs may play a crucial role in initiating the differentiation of ECs. TYROBOP-positive endothelial cells (ECs) exhibited the strongest crosstalk with malignant cells, likely mediated by TWEAK, a multifunctional cytokine. TYROBP-positive ECs exhibited significant expression of TME-related genes, unique metabolic and immunological profiles. Importantly, OS patients with low enrichment of TYROBP-positive ECs had better prognoses and a lower risk of metastasis. Finally, vitro assays confirmed that TWEAK was significantly increased in ECs-conditioned medium (ECs-CM) when TYROBP was over-expressed in EC cells, and could promote the proliferation and migration of OS cells. Conclusion: We concluded that TYROBP-positive ECs may be the initiating cells and play a crucial role in the promotion of malignant cell progression. TYROBP-positive ECs have a unique metabolic and immunological profile and may interact with malignant cells through the secretion of TWEAK.

6.
Insects ; 14(3)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36975901

RESUMEN

The olfactory system in insects are crucial for recognition of host plants and oviposition sites. General odorant binding proteins (GOBPs) are thought to be involved in detecting odorants released by host plants. Orthaga achatina (Lepidoptera: Pyralidae) is one of the most serious pests of camphor trees, Cinnamomum camphora (L.) Presl, an important urban tree species in southern China. In this study, we study the GOBPs of O. achatina. Firstly, two full-length GOBP genes (OachGOBP1 and OachGOBP2) were successfully cloned according to transcriptome sequencing results, and real-time quantitative PCR measurements showed that both GOBP genes were specifically expressed in the antennae of both sexes, proposing their important roles in olfaction. Then, both GOBP genes were heterologous expressed in Escherichia coli and fluorescence competitive binding assays were conducted. The results showed that OachGOBP1 could bind Farnesol (Ki = 9.49 µM) and Z11-16: OH (Ki = 1.57 µM). OachGOBP2 has a high binding affinity with two camphor plant volatiles (Farnesol, Ki = 7.33 µM; α-Phellandrene, Ki = 8.71 µM) and two sex pheromone components (Z11-16: OAc, Ki = 2.84 µM; Z11-16: OH, Ki = 3.30 µM). These results indicate that OachGOBP1 and OachGOBP2 differ in terms of odorants and other ligands. Furthermore, key amino acid residues that bind to plant volatiles were identified in GOBPs using 3-D structure modeling and ligand molecular docking, predicting the interactions between the GOBPs and the host plant volatiles.

7.
Pestic Biochem Physiol ; 184: 105097, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35715036

RESUMEN

Pheromone-binding proteins (PBPs) play important roles in perception of insect sex pheromones, functioning to recognize and transport pheromone components onto the olfactory receptors of the odorant sensing neurons. Orthaga achatina, a serious pest of camphor trees, uses a mixture of three Type I (Z11-16:OAc, Z11-16:OH and Z11-16:Ald) and one Type II (Z3,Z6,Z9,Z12,Z15-23:H) sex pheromone components in its sex communication, in which Z11-16:OAc is the major component and others are minor components. In this study, we for the first time demonstrated that the three PBPs differentiated in recognition among pheromone components in a moth using mixed-type sex pheromones. First, tissue expression study showed that all three PBPs of O. achatina were expressed only in antennae and highly male-biased, suggesting their involvement in perception of the sex pheromones. Second, the three PBPs were expressed in Escherichia coli and the binding affinities of PBPs to four sex pheromone components and some pheromone analogs were determined by the fluorescence competition binding assays. The results showed that OachPBP1 bound all four sex pheromone components with high binding affinity, while OachPBP2 had high or moderate binding affinity only to three Type I components, and OachPBP3 had high binding affinity only to three minor pheromone components. Furthermore, key amino acid residues that bind to sex pheromone components were identified in three PBPs by 3-D structure modeling and ligand molecular docking, predicting the interactions between PBPs and pheromone components. Our study provides a fundamental insight into the olfactory mechanism in moths that use mixed-type sex pheromones.


Asunto(s)
Mariposas Nocturnas , Atractivos Sexuales , Animales , Proteínas Portadoras , Proteínas de Insectos/metabolismo , Simulación del Acoplamiento Molecular , Mariposas Nocturnas/metabolismo , Feromonas/metabolismo , Atractivos Sexuales/metabolismo
8.
Ann Ital Chir ; 92: 102-107, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35342099

RESUMEN

BACKGROUND: The injury mechanism of a pelvic fracture is primarily high-energy injury, and it is easily combined with injuries to other tissues and organs. This study aimed to investigate the clinical effectiveness of early diagnosis and treatment of pelvic fractures and associated injuries in children. METHODS: The diagnosis and treatment of 60 children with pelvic fractures and associated injuries who were admitted to our hospital from January 2005 to December 2016 were retrospectively analyzed. Among these patients, 36 were male, and 24 were female. The patients' ages ranged within 2-15 years, with an average of 7.6 years old. The pelvic fractures were classified based on the Torode and Zieg classification; among the patients, 12 had type I, 16 had type II, 20 had type III, and 12 had type IV. All patients received early diagnosis, immediate anti-shock measures, aggressive treatment of associated injuries, and early reduction and fixation of the pelvic fractures after admission. RESULTS: Of the 60 patients, 28 had injuries caused by traffic accidents, 26 had injuries caused by falling from high places, and 16 had injuries caused by compressing or crushing. Eight patients had unilateral pubic bone fracture or pubic symphysis separation that involved posterior pelvic fracture or sacroiliac joint separation, and two had fractures that affected the anterior ring or acetabulum. Moreover, 26 patients had hemorrhagic shock, 18 had traumatic brain injury, 14 had fractures at other sites, 8 had pelvic large vessel injuries, 8 had ipsilateral femoral and proximal femoral fractures, 8 had retroperitoneal hematoma, 8 had urinary system injury, 6 had perineal laceration and vaginal trauma, 6 had spinal cord injury, 4 had intestinal injuries, 4 had soft tissue contusions, and 4 had sacral nerve injury. During the follow-up (average: 48 months), six children died. The evaluation results of the curative effect were excellent in 32 children, good in 18, and poor in 4; the 'excellent' and 'good' rate was 92.5% (50/54). CONCLUSION: Early diagnosis, reduction, and fixation and timely treatment of associated injuries might achieve better clinical efficacy and are worthy of clinical promotion. KEY WORDS: Associated Injuries, Childhood, Diagnosis, Fracture, Pelvic, Treatment.


Asunto(s)
Fracturas Óseas , Huesos Pélvicos , Fracturas de la Columna Vertebral , Accidentes de Tránsito , Adolescente , Niño , Preescolar , Femenino , Fracturas Óseas/diagnóstico , Fracturas Óseas/etiología , Fracturas Óseas/terapia , Humanos , Masculino , Huesos Pélvicos/lesiones , Huesos Pélvicos/cirugía , Estudios Retrospectivos
9.
Insect Biochem Mol Biol ; 141: 103719, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34999200

RESUMEN

General odorant-binding proteins (GOBPs) are long considered responsible for the perception of plant odorants. In this study with the important noctuid pest Spodoptera litura, we functionally characterized that GOBP2 is also involved in the perception of sex pheromone components using in vivo CRISPR/Cas9 technique. First, the GOBP2 sgRNA and Cas9 protein were injected into the newly laid insect eggs, resulting in a 35.6% target mutagenesis in G0 moths. Then, the homozygous GOBP2 knockout strain (GOBP2-/-) was obtained after the screening of three generations. The knockout male and female moths displayed a significant reduction in EAG responses to the sex pheromone components, and the knockout females also displayed a significant reduction to plant odorants. In the behavioral assay of food choice, GOBP2-/- larvae lost the preference to artificial diet added with the major sex pheromone component Z9, E11-tetradecadienyl acetate (Z9, E11-14:Ac), whereas the WT larvae highly preferred the pheromone diet. Y-tube olfactometer assay and direct pheromone stimulation assay showed that GOBP2-/- male adults reduced significantly than WT males in percentages of choice, hair pencil displaying and mating attempt to Z9, E11-14:Ac. In the oviposition test, GOBP2-/- females showed significantly reduced preference for the soybean plants compared to the WT females. Our study demonstrated that GOBP2 plays an important role in perceiving sex pheromones in adult and larval stages, providing new insight into sex pheromone perception and a potential target for sex pheromone-based behavioral regulation in the pest.


Asunto(s)
Proteínas de Insectos/genética , Mariposas Nocturnas/genética , Receptores Odorantes/genética , Atractivos Sexuales/metabolismo , Animales , Sistemas CRISPR-Cas , Proteínas de Insectos/metabolismo , Larva/genética , Larva/crecimiento & desarrollo , Larva/metabolismo , Mariposas Nocturnas/crecimiento & desarrollo , Mariposas Nocturnas/metabolismo , Receptores Odorantes/metabolismo
10.
Insects ; 11(3)2020 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-32197457

RESUMEN

Pheromone receptors (PRs) found in the antennae of male moths play a vital role in the recognition of sex pheromones released by females. The fall armyworm (FAW), Spodoptera frugiperda, is a notorious invasive pest, but its PRs have not been reported. In this report, six candidate PRs (SfruOR6, 11, 13, 16, 56 and 62) suggested by phylogenetic analysis were cloned, and their tissue-sex expression profiles were determined by quantitative real-time PCR (qPCR). All six genes except for SfruOR6 were highly and specifically expressed in the antennae, with SfruOR6, 13 and 62 being male-specific, while the other three (SfruOR11, 16 and 56) were male biased, suggesting their roles in sex pheromone perception. A functional analysis by the Xenopus oocyte system further demonstrated that SfruOR13 was highly sensitive to the major sex pheromone component Z9-14:OAc and the pheromone analog Z9,E12-14:OAc, but less sensitive to the minor pheromone component Z9-12:OAc; SfruOR16 responded weakly to pheromone component Z9-14:OAc, but strongly to pheromone analog Z9-14:OH; the other four candidate PRs did not respond to any of the four pheromone components and four pheromone analogs. This study contributes to clarifying the pheromone perception in the FAW, and provides potential gene targets for developing OR-based pest control techniques.

11.
World J Gastroenterol ; 23(34): 6252-6260, 2017 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-28974891

RESUMEN

AIM: To investigate the potential effect of curcumin on hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) and the underlying mechanism. METHODS: A HepG2.2.15 cell line stably transfected with HBV was treated with curcumin, and HBV surface antigen (HBsAg) and e antigen (HBeAg) expression levels were assessed by ELISA. Intracellular HBV DNA replication intermediates and cccDNA were detected by Southern blot and real-time PCR, respectively. The acetylation levels of histones H3 and H4 were measured by Western blot. H3/H4-bound cccDNA was detected by chromatin immunoprecipitation (ChIP) assays. The deacetylase inhibitors trichostatin A and sodium butyrate were used to study the mechanism of action for curcumin. Additionally, short interfering RNAs (siRNAs) targeting HBV were tested along with curcumin. RESULTS: Curcumin treatment led to time- and dose-dependent reductions in HBsAg and HBeAg expression and significant reductions in intracellular HBV DNA replication intermediates and HBV cccDNA. After treatment with 20 µmol/L curcumin for 2 d, HBsAg and cccDNA levels in HepG2.2.15 cells were reduced by up to 57.7% (P < 0.01) and 75.5% (P < 0.01), respectively, compared with levels in non-treated cells. Meanwhile, time- and dose-dependent reductions in the histone H3 acetylation levels were also detected upon treatment with curcumin, accompanied by reductions in H3- and H4-bound cccDNA. Furthermore, the deacetylase inhibitors trichostatin A and sodium butyrate could block the effects of curcumin. Additionally, transfection of siRNAs targeting HBV enhanced the inhibitory effects of curcumin. CONCLUSION: Curcumin inhibits HBV gene replication via down-regulation of cccDNA-bound histone acetylation and has the potential to be developed as a cccDNA-targeting antiviral agent for hepatitis B.


Asunto(s)
Antivirales/farmacología , Curcumina/farmacología , ADN Circular/metabolismo , ADN Viral/metabolismo , Antígenos de Superficie de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/efectos de los fármacos , Histonas/metabolismo , Acetilación/efectos de los fármacos , Ácido Butírico/farmacología , Inmunoprecipitación de Cromatina , Replicación del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Sinergismo Farmacológico , Proteína p300 Asociada a E1A/antagonistas & inhibidores , Células Hep G2 , Antígenos e de la Hepatitis B/metabolismo , Virus de la Hepatitis B/genética , Inhibidores de Histona Desacetilasas/farmacología , Humanos , Ácidos Hidroxámicos/farmacología , Interferencia de ARN , ARN Interferente Pequeño/farmacología , Reacción en Cadena en Tiempo Real de la Polimerasa
12.
Oncotarget ; 7(12): 14188-98, 2016 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-26893358

RESUMEN

As a naturally occurring inhibitor of mTOR, accumulated evidence has suggested that DEPTOR plays a pivotal role in suppressing the progression of human malignances. However, the function of DEPTOR in the development of esophageal squamous cell carcinoma (ESCC) is still unclear. Here we report that the expression of DEPTOR is significantly reduced in tumor tissues derived from human patients with ESCC, and the downregulation of DEPTOR predicts a poor prognosis of ESCC patients. In addition, we found that the expression of DEPTOR negatively regulates the tumorigenic activities of ESCC cell lines (KYSE150, KYSE510 and KYSE190). Furthermore, ectopic DEPTOR expression caused a significant suppression of the cellular proliferation, migration and invasion of KYSE150 cells, which has the lowest expression level of DEPTOR in the three cell lines. Meanwhile, CRISPR/Cas9 mediated knockout of DEPTOR in KYSE-510 cells significantly promoted cellular proliferation, migration and invasion. In addition, in vivo assays further revealed that tumor growth was significantly inhibited in xenografts with ectopic DEPTOR expression as compared to untreated KYSE150 cells, and was markedly enhanced in DEPTOR knockout KYSE-510 cells. Biochemical studies revealed that overexpression of DEPTOR led to the suppression of AKT/mTOR pathway as evidenced by reduced phosphorylation of AKT, mTOR and downstream SGK1, indicating DEPTOR might control the progression of ESCC through AKT/mTOR signaling pathway. Thus, these findings, for the first time, demonstrated that DEPTOR inhibits the tumorigenesis of ESCC cells and might serve as a potential therapeutic target or prognostic marker for human patients with ESCC.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/secundario , Neoplasias Esofágicas/patología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Animales , Apoptosis , Carcinoma de Células Escamosas/metabolismo , Movimiento Celular , Proliferación Celular , Progresión de la Enfermedad , Neoplasias Esofágicas/metabolismo , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Humanos , Metástasis Linfática , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Invasividad Neoplásica , Fosforilación , Pronóstico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Tasa de Supervivencia , Serina-Treonina Quinasas TOR/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Huan Jing Ke Xue ; 37(12): 4524-4530, 2016 Dec 08.
Artículo en Chino | MEDLINE | ID: mdl-29965290

RESUMEN

During takeoff, high engine thrust and large fuel consumption are required to produce enough power for aircraft lift-off which has more impacts on human health and environment than the other activities. Boeing 737-800 was selected as a typical type in the study. Based on simulation of aircraft performance, air pollution emissions were accurately calculated for different takeoff processes. According to the results, NOx was the most abundant emission during takeoff. Emissions of NOx, CO, HC, and SO2 during takeoff with normal method were 4.849, 0.062, 0.031, 0.229 kg respectively. The assumed temperature method could be used to reduce thrust by setting an assumed temperature which was greater than actual temperature. This method resulted in decreased NOx emission and increased CO emission. And emissions of HC and SO2 had no significant changes. Compared with these results, the emissions calculated by ICAO emission model led to relatively large errors. And the emission level of normal takeoff method was approximately equal to the emission level of small cars traveling 9508 km. The modified model provides the basis for the accurate estimation of the air pollution emission inventory of airport.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(8): 2035-8, 2013 Aug.
Artículo en Chino | MEDLINE | ID: mdl-24159840

RESUMEN

Diluted magnetic semiconductors Zn(1-x) Fe(x)O nanoparticles with different content (x = 0, 0.01, 0.05, 0.10 and 0.20) were successfully synthesized via hydrothermal method. The X-ray diffraction (XRD) shows that the samples are wurtzite structure and metallic Fe or other secondary phases were not found in the samples. The transmission electron microscopy (TEM) shows that the morphology is nanoparticles with good dispersion, and the lattice is clearly visible. Raman scattering spectrum (Raman spectra) shows that E2 (High) mode broadened, shifted towards the high-frequencies side and decreased the peak intensity. Photoluminescence spectra (PL) shows that the peaks moved to lower energy and the photoluminescence intensity was quenched with increasing Fe doping concentration. The ultraviolet-visible spectrophotometry (UV-Vis) indicates that the optical band gap decreased and red shift occured. All the results indicate that Fe3+ ions successfully substituted for Zn2+ and were incorporated into the crystal lattice of ZnO.

15.
Mar Biotechnol (NY) ; 15(5): 526-39, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23535913

RESUMEN

In zebrafish and other vertebrates, primordial germ cells (PGCs) are a population of embryonic cells that give rise to sperm and eggs in adults. Any type of genetically manipulated lines have to be originated from the germ cells of the manipulated founders, thus it is of great importance to establish an effective technology for highly specific PGC-targeted gene manipulation in vertebrates. In the present study, we used the Cre/loxP recombinase system and Gal4/UAS transcription system for induction and regulation of mRFP (monomer red fluorescent protein) gene expression to achieve highly efficient PGC-targeted gene expression in zebrafish. First, we established two transgenic activator lines, Tg(kop:cre) and Tg(kop:KalTA4), to express the Cre recombinases and the Gal4 activator proteins in PGCs. Second, we generated two transgenic effector lines, Tg(kop:loxP-SV40-loxP-mRFP) and Tg(UAS:mRFP), which intrinsically showed transcriptional silence of mRFP. When Tg(kop:cre) females were crossed with Tg(kop:loxP-SV40-loxP-mRFP) males, the loxP flanked SV40 transcriptional stop sequence was 100 % removed from the germ cells of the transgenic hybrids. This led to massive production of PGC-specific mRFP transgenic line, Tg(kop:loxP-mRFP), from an mRFP silent transgenic line, Tg(kop:loxP-SV40-loxP-mRFP). When Tg(kop:KalTA4) females were crossed with Tg(UAS:mRFP) males, the hybrid embryos showed PGC specifically expressed mRFP from shield stage till 25 days post-fertilization (pf), indicating the high sensitivity, high efficiency, and long-lasting effect of the Gal4/UAS system. Real-time PCR analysis showed that the transcriptional amplification efficiency of the Gal4/UAS system in PGCs can be about 300 times higher than in 1-day-pf embryos. More importantly, when the UAS:mRFP-nos1 construct was directly injected into the Tg(kop:KalTA4) embryos, it was possible to specifically label the PGCs with high sensitivity, efficiency, and persistence. Therefore, we have established two targeted gene expression platforms in zebrafish PGCs, which allows us to further manipulate the PGCs of zebrafish at different levels.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Expresión Génica , Marcación de Gen/métodos , Ingeniería Genética/métodos , Células Germinativas/metabolismo , Integrasas/metabolismo , Factores de Transcripción/metabolismo , Proteínas de Pez Cebra/metabolismo , Pez Cebra/metabolismo , Animales , Cruzamientos Genéticos , Femenino , Proteínas Luminiscentes , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa , Coloración y Etiquetado , Pez Cebra/genética , Proteína Fluorescente Roja
16.
J Mol Model ; 19(4): 1553-63, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23271308

RESUMEN

The computations of the geometries, electronic structures, dipole moments and polarizabilities for indoline and triphenylamine (TPA) based dye sensitizers, including D102, D131, D149, D205, TPAR1, TPAR2, TPAR4, and TPAR5, were performed using density functional theory, and the electronic absorption properties were investigated via time-dependent density functional theory with polarizable continuum model for solvent effects. The population analysis indicates that the donating electron capability of TPA is better than that of indoline group. The reduction driving forces for the oxidized D131 and TPAR1 are slightly larger than that of other dyes because of their lower highest occupied molecular orbital level. The absorption properties and molecular orbital analysis suggest that the TPA and 4-(2,2diphenylethenyl)phenyl substituent indoline groups are effective chromophores in intramolecular charge transfer (IMCT), and they play an important role in sensitization of dye-sensitized solar cells (DSCs). The better performance of D205 in DSCs results from more IMCT excited states with larger oscillator strength and higher light harvesting efficiency. While for TPA dyes, the longer conjugate bridges generate the larger oscillator strength and light harvesting efficiency, and the TPAR1 and TPAR4 have larger free energy change for electron injection and dye regeneration.

17.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 3): m374, 2011 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-21522296

RESUMEN

In the title complex, [Mg(C(2)H(3)O(3))(H(2)O)(4)]NO(3), the Mg(II) cation is hexa-coordinated by four O atoms from water mol-ecules and two O atoms from a 2-hy-droxy-acetate ligand in a distorted octa-hedral coordination geometry. The structure exhibits a three-dimensional supra-molecular network, which is stabilized by nine different O-H⋯O hydrogen bonds.

18.
Environ Monit Assess ; 176(1-4): 157-67, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20568008

RESUMEN

A total of 11 sediment samples were collected from the sites along Haihe River-Bohai Bay, with site 1 at the beginning of Haihe River and site 11 in Bohai Bay, about 150 km away from site 1. Quinone profiles were used for the analysis of microbial community as influenced by pollutants in water and sediments, such as heavy metals, and other environmental factors. Nineteen species of quinones were found at site 1 while only six species at sites 10 and 11. Both the diversity of quinone species (DQ) and the number of quinones were higher in the sediments from Haihe River and the near-sea area of Bohai Bay than in those from the deep-sea area. The ß diversity values were significantly higher, while Jaccard indexes of similarity were much lower among non-contiguous pairs of sites as compared with the contiguous ones. Cluster analysis indicated that quinone profiles may be grouped into two main clusters (sites 1-7 and sites 8-11), and there were higher similarities within the groups than between groups. Quinone species composition varied at different sites. Ubiquinones such as UQ-8, UQ-9, and UQ-10 and menaquinones such as MK-6, MK-7, MK-8 were isolated from all the sites and accounted for the largest proportions. Pearson correlation analysis revealed that both the number of quinone species and DQ correlated positively with total organic carbon contents in water and sediments, but negatively correlated with salinity and electroconductivity and did not correlate significantly with heavy metal contents in water.


Asunto(s)
Sedimentos Geológicos/análisis , Sedimentos Geológicos/microbiología , Metales Pesados/análisis , Quinonas/análisis , Microbiología del Agua , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Ríos
19.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 6): m606, 2010 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-21579268

RESUMEN

In the title centrosymmetric dinuclear Eu(III) complex, [Eu(2)(CH(3)COO)(6)(C(12)H(8)N(2))(2)], each Eu(III) cation is coordinated by seven O atoms from five acetate anions and two N atoms from one phenanthroline ligand in a distorted tricapped trigonal-prismatic geometry. Four acetate anions bridge two Eu(III) cations to form the dinuclear complex, with an Eu⋯Eu distance of 3.9409 (8) Å. Weak inter-molecular C-H⋯O hydrogen bonding is present in the crystal structure.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(3): 716-21, 2009 Mar.
Artículo en Chino | MEDLINE | ID: mdl-19455807

RESUMEN

Random sample approaches were employed for the sampling scenario with 41 spots sampled in topsoil (0-20 cm) in Red Soil ecology experimental station, Poyang Lake ecology experimental station, and Qianyanzhou ecology experimental station in Jiangxi Province by global position system (GPS). The hyperspectral reflectance spectra of soil samples were measured in ultraviolet, visible, and near infrared region from 225 to 2 500 nm with an interval of 1nm. The change characteristics of soil hyperspectral reflectance curves were studied. The objective of the present paper was to develop a methodology to estimate soil attributes using spectral reflectance. The multiple linear stepwise regression analysis method was used to build hyperspectral models for the prediction of soil attributes, with 22 bands and 13 "reflectance inflexion differences" as independent variables and the soil attributes as dependent variables respectively. Root mean squared error (RMSE) was introduced to test the predictability and precision of the models, and the correlation coefficient was used to evaluate the stability of the models. Some attributes, such pH, SOC, TN, TP, CEC and available N, had the correlation coefficients higher than 0.80, while the value of TK, available P and available K was about 0.68. The results show that the method is feasible to predict the concentration of some soil attributes, while further study should be done for others attributes.

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