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1.
Appl Opt ; 63(3): 721-729, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38294385

RESUMO

The infrared radiation properties of a satellite provide essential information for space target recognition. In this study, a 3D model of a satellite is obtained using a 3D reconstruction algorithm based on deep learning. The transient temperature field distribution on the target surface is simulated using the ANSYS finite element analysis method by integrating the solar zenith angle, the position of the satellite orbit, and the dynamic angle of the detector. The infrared radiation model is used to analyze the influence of target surface temperature, orbit position, and rotation angle on infrared radiation. The calculated results show that, under the set parameters, the temperature range of all targets is 280-380 K, and the temperature distribution determines the variation trend of radiation intensity. The variation trends of radiation intensity presented by different motion postures of satellites differ considerably. The radiation intensity variation of the triaxial stabilized attitude is relatively stable, whereas the radiation intensity of the spin-stabilized attitude exhibits remarkable periodic fluctuations. The periodic motion of satellite orbit leads to periodic fluctuations in infrared radiation. The obtained infrared radiation data provide support for target detection, tracking, recognition, and infrared detector parameter design.

2.
J Pineal Res ; 74(2): e12846, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36428267

RESUMO

With the rapid change of people's lifestyle, more childbearing couples live with irregular schedules (i.e., staying up late) and suffer from decreased fertility and abortion, which can be caused by luteal phase defect (LPD). We used continuous light-exposed mice as a model to observe whether continuous light exposure may affect luteinization and luteal function. We showed that the level of progesterone in serum reduced (p < .001), the number of corpus luteum (CL) decreased (p < .01), and the expressions of luteinization-related genes (Lhcgr, Star, Ptgfr, and Runx2), clock genes (Clock and Per1), and Mt1 were downregulated (p < .05) in the ovaries of mice exposed to continuous light, suggesting that continuous light exposure induces defects in luteinization and luteal functions. Strikingly, injection of melatonin (3 mg/kg) could improve luteal functions in continuous light-exposed mice. Moreover, we found that, after 2 h of hCG injection, the level of pERK1/2 in the ovary decreased in the continuous light group, but increased in the melatonin administration group, suggesting that melatonin can improve LPD caused by continuous light exposure through activating the ERK1/2 pathway. In summary, our data demonstrate that continuous light exposure affects ovary luteinization and luteal function, which can be rescued by melatonin.


Assuntos
Melatonina , Ovário , Feminino , Gravidez , Camundongos , Animais , Ovário/metabolismo , Camundongos Endogâmicos ICR , Melatonina/farmacologia , Melatonina/metabolismo , Corpo Lúteo/metabolismo , Progesterona/metabolismo , Luteinização
3.
Microvasc Res ; 139: 104260, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624308

RESUMO

OBJECTIVES: To explore whether minimally modified low-density lipoprotein (mmLDL) upregulates mesenteric arterial 5-hydroxytryptamine 1B (5-HT1B) receptor expression by activating the JAK2/STAT3 signaling pathway. METHODS: Mice were randomly divided into the following groups: the normal saline (NS), LDL, mmLDL, mmLDL+galiellactone (GL, a JAK2/STAT3 pathway inhibitor), and mmLDL+DMSO groups. The dose-response curve of mesenteric arterial ring constriction after administration of 5-carboxamidotryptamine (5-CT), an agonist of 5-HT1B, was recorded with a microvascular tensiometer. JAK2, p-JAK2, STAT3, p-STAT3, and 5-HT1B receptor protein expression levels were determined by Western blotting. 5-HT1B receptor mRNA levels were measured by RT-PCR. 5-HT1B receptor protein expression was determined by immunofluorescence. RESULTS: Injection of mmLDL into the tail vein significantly increased the contractile dose-response curve after 5-CT stimulation, as the Emax was 82.15 ±â€¯6.15% in the NS group and 171.88 ±â€¯5.78% in the mmLDL group (P < 0.01); significantly elevated 5-HT1B receptor mRNA and protein expression levels; and significantly increased p-JAK2 and p-STAT3 protein expression levels. After intraperitoneal injection of GL, the vasoconstrictive response was significantly reduced compared with that in the mmLDL group, as the Emax was decreased to 97.14 ±â€¯1.20% (P < 0.01); 5-HT1B receptor mRNA and protein expression levels were significantly reduced; STAT3 phosphorylation and p-JAK2 and p-STAT3 protein expression were not significantly changed; and 5-HT1B receptor expression was altered via inhibition of p-STAT3 binding to DNA, which suppressed transcription. CONCLUSIONS: mmLDL can upregulate 5-HT1B receptor expression in mouse mesenteric arteries by activating the JAK2/STAT3 signaling pathway.


Assuntos
Janus Quinase 2/metabolismo , Lipoproteínas LDL/farmacologia , Artérias Mesentéricas/efeitos dos fármacos , Receptor 5-HT1B de Serotonina/metabolismo , Fator de Transcrição STAT3/metabolismo , Vasoconstrição/efeitos dos fármacos , Animais , Ativação Enzimática , Feminino , Masculino , Artérias Mesentéricas/enzimologia , Camundongos , Fosforilação , Receptor 5-HT1B de Serotonina/genética , Transdução de Sinais , Regulação para Cima
4.
Hum Mol Genet ; 28(20): 3422-3430, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31384951

RESUMO

Germ cell-derived genomic structure variants not only drive the evolution of species but also induce developmental defects in offspring. The genomic structure variants have different types, but most of them are originated from DNA double-strand breaks (DSBs). It is still not well known whether DNA DSBs exist in adult mammalian oocytes and how the growing and fully grown oocytes repair their DNA DSBs induced by endogenous or exogenous factors. In this study, we detected the endogenous DNA DSBs in the growing and fully grown mouse oocytes and found that the DNA DSBs mainly localized at the centromere-adjacent regions, which are also copy number variation hotspots. When the exogenous DNA DSBs were introduced by Etoposide, we found that Rad51-mediated homologous recombination (HR) was used to repair the broken DNA. However, the HR repair caused the chromatin intertwined and impaired the homologous chromosome segregation in oocytes. Although we had not detected the indication about HR repair of endogenous centromere-adjacent DNA DSBs, we found that Rad52 and RNA:DNA hybrids colocalized with these DNA DSBs, indicating that a Rad52-dependent DNA repair might exist in oocytes. In summary, our results not only demonstrated an association between endogenous DNA DSBs with genomic structure variants but also revealed one specific DNA DSB repair manner in oocytes.


Assuntos
Segregação de Cromossomos/fisiologia , Quebras de DNA de Cadeia Dupla , Reparo do DNA/fisiologia , Meiose/fisiologia , Oócitos/metabolismo , Animais , Segregação de Cromossomos/genética , Reparo do DNA/genética , Feminino , Infertilidade Feminina/genética , Masculino , Meiose/genética , Camundongos
5.
Biol Reprod ; 105(5): 1234-1245, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34467391

RESUMO

Within the development of ovarian follicle, in addition to cell proliferation and differentiation, sophisticated cell-cell cross talks are established among follicular somatic cells such as granulosa cells (GCs) and theca cells. To systematically reveal the cell differentiation and signal transductions in follicular somatic cells, we collected the mouse follicular somatic cells from secondary to ovulatory stage, and analyzed the single cell transcriptomes. Having data filtered and screened, we found 6883 high variable genes in 4888 single cells. Then follicular somatic cells were clustered into 26 cell clusters, including 18 GC clusters, 4 theca endocrine cell (TEC) clusters, and 4 other somatic cell clusters, which include immune cells and Acta2 positive theca externa cells. From our data, we found there was metabolic reprogramming happened during GC differentiation. We also found both Cyp19a1 and Cyp11a1 could be expressed in TECs. We analyzed the expression patterns of genes associated with cell-cell interactions such as steroid hormone receptor genes, insulin signaling genes, and cytokine/transformation growth factor beta associated genes in all cell clusters. Lastly, we clustered the highly variable genes into 300 gene clusters, which could be used to search new genes involved in follicle development. These transcriptomes of follicular somatic cells provide us potential clues to reveal how mammals regulating follicle development and could help us find targets to improve oocyte quality for women with low fertility.


Assuntos
Comunicação Celular/genética , Expressão Gênica/fisiologia , Folículo Ovariano/metabolismo , Transdução de Sinais , Transcriptoma , Animais , Feminino , Camundongos , Análise de Sequência de RNA , Análise de Célula Única
6.
Appl Opt ; 59(10): 2992-3001, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400576

RESUMO

The Visible Infrared Imaging Radiometer Suite (VIIRS) aboard the NOAA-20 satellite regularly performs on-orbit radiometric calibration of its reflective solar bands (RSBs) through observations of an onboard sunlit solar diffuser (SD). The incident sunlight passes through an attenuation screen (the SD screen) and then scatters off the SD to provide a radiance source for the calibration. The on-orbit change of the SD's bidirectional reflectance distribution function (BRDF), referred to as the H-factor, is determined by an onboard solar diffuser stability monitor (SDSM) whose eight detectors alternately observe the Sun through another attenuation screen (the SDSM screen) and the sunlit SD. The products of the SD screen transmittance and the BRDF at the mission start for both the SDSM and RSBs and the SDSM screen effective transmittance were measured prelaunch. Large unrealistic undulations in the retrieved H-factor were seen when using the prelaunch screen functions. To improve the accuracy of the retrieved H-factor, shortly after the satellite launch, 15 yaw maneuvers were performed to further characterize the screens. Although significantly improved, the H-factor derived using the screen functions determined from the yaw maneuver data still has large unrealistic undulations, revealing that the solar azimuth angular step size of the yaw maneuvers is too large. In this paper, we add high-quality regular on-orbit SD calibration data to the yaw maneuver data to further improve the relative product of the SD screen effective transmittance and the BRDF at the mission start for the SDSM and the SDSM screen relative effective transmittance. The H-factor time series derived from the newly determined screen transmittance functions is much smoother than that derived from using only the yaw maneuver data and thus considerably improves the radiometric calibration accuracy.

7.
Immunopharmacol Immunotoxicol ; 41(2): 258-266, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31062632

RESUMO

Background and aim: Alpha-momorcharin (α-MMC) is a type I ribosome-inactivating protein (RIP) that is purified from Momordica charantia. Despite its strong antitumor activities, α-MMC exerts the undesirable immunotoxicity effects of hypersensitivity or immunosuppression. Since α-MMC is a plant protein, its application in vivo can easily induce hypersensitivity, but its immunosuppressive mechanism is still unclear. Materials and methods: The toxicity of α-MMC to peripheral blood cells and the cytokine expression in peripheral blood mononuclear cells (PBMCs) and spleen immune cells were measured in rats. For further confirmation, experiments were performed in vitro with the mononuclear cell line THP-1, B lymphocyte cell line WIL2-S and T lymphocyte cell line Jurkat. Results: High doses of α-MMC (3.0 mg/kg) resulted in weight loss in rats, a decreased percentage of monocytes, and increased percentages of eosinophils and basophils. Both high-dose and low-dose (1.0 mg/kg) α-MMC inhibited cytokine expression in PBMCs and increased cytokine expression in spleen T cells. In in vitro, α-MMC mainly acted on THP-1 cells, with effects including high dose-induced apoptosis and low dose-induced regulation of inhibitory cytokine expression. Conclusions: The action of α-MMC on immune cells mainly affects monocytes, thereby eliciting its immunosuppressive effect. Its mode of action is to guide functional immunosuppressive regulation at low doses and induce apoptosis at high doses. As the monocytes would be recruited into tumor tissues and are polarized into tumor-associated macrophages, the selective cytotoxicity and cytokine release regulation of α-MMC in monocytes may be an important mechanism of its antitumor effects.


Assuntos
Apoptose/efeitos dos fármacos , Citocinas/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Monócitos/imunologia , Proteínas Inativadoras de Ribossomos/farmacologia , Animais , Apoptose/imunologia , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Células Jurkat , Monócitos/patologia , Ratos , Ratos Sprague-Dawley , Células THP-1
8.
Anal Chem ; 90(19): 11495-11502, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30188118

RESUMO

By virtue of its self-illuminating mechanism, the bioluminescence resonance energy transfer (BRET) technique has recently emerged as a promising platform for point-of-care (POC) diagnostics. However, due to the difficulty of incorporating generic affinity elements, such as aptamers and antibodies, current BRET-based methods are still not applicable to most clinically important biomarkers. Furthermore, the inability of these methods to amplify BRET signals leads to limited sensitivity in some applications. Here, we present a modular strategy for amplified BRET detection of protein biomarkers in human peripheral blood samples. In this strategy, a DNA-templated bioluminescent module was constructed by simultaneously binding luciferase and green fluorescent protein to one DNA template in a site-specific manner. The proposed modules showed high energy transfer efficiency and could be assembled into long self-illuminating polymers. Owing to this modular design, aptamers and antibodies were rationally incorporated, enabling specific assembly of multiple bioluminescent modules on one target. This strategy realized amplified BRET assays for human α-thrombin and prostate specific antigen (PSA) with the detection limit in the picomolar range using either a spectrophotometer or a smartphone. The modularity of our strategy allowed detection of different biomarkers by simple exchange of affinity elements. Furthermore, the self-illumination and isothermal amplification performance of this strategy make it an attractive tool for POC diagnostics.


Assuntos
Técnicas de Transferência de Energia por Ressonância de Bioluminescência/métodos , Biomarcadores/análise , DNA/química , Humanos , Imunoensaio , Limite de Detecção , Sistemas Automatizados de Assistência Junto ao Leito , Antígeno Prostático Específico/análise , Smartphone , Trombina/análise
9.
Reprod Fertil Dev ; 29(2): 223-233, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26193799

RESUMO

Mitogen-activated protein kinase (MAPK)-activated protein kinase 2 (MK2), a direct substrate of p38 MAPK, plays key roles in multiple cellular processes. In the present study, we showed that MK2 affected not only cumulus expansion, but also the oocyte meiotic cell cycle in porcine oocytes. Inhibition of MK2 arrested oocytes at the germinal vesicle (GV) stage or the prometaphase I/metaphase I stage. Unlike in mouse oocytes, where phosphorylated (p-) MK2 was localised at the minus end of spindle microtubules and close to the spindle poles, in porcine oocytes p-MK2 was concentrated at the spindle equator and localised at the plus end of spindle microtubules. Knockdown or inhibition of MK2 resulted in spindle defects: spindles were surrounded by irregular chromosome non-disjunction or by chromosomes detached from the spindles. MK2 regulated spindle organisation and chromosome alignment by connecting microtubules with kinetochores. In addition, unlike in mitotic cells and meiotic mouse oocytes, the MK2-p38 MAPK pathway may not play an important role during meiotic cell cycle in porcine oocytes. In conclusion, MK2 is an important regulator of porcine oocyte meiotic maturation.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Meiose/fisiologia , Oócitos/metabolismo , Oogênese/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Fuso Acromático/metabolismo , Animais , Células do Cúmulo/metabolismo , Feminino , Fosforilação , Suínos
10.
Appl Opt ; 56(31): 8676-8686, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29091685

RESUMO

The visible infrared imaging radiometer suite on the Suomi National Polar-orbiting Partnership satellite calibrates its reflective solar bands through observations of a sunlit solar diffuser (SD) panel. Sunlight passes through a perforated plate, referred to as the SD screen, before reaching the SD. It is critical to know whether the SD screen transmittance measured prelaunch is accurate. Several factors such as misalignments of the SD panel and the measurement apparatus could lead to errors in the measured transmittance and thus adversely impact on-orbit calibration quality through the SD. We develop a mathematical model to describe the transmittance as a function of the angles that incident light makes with the SD screen, and apply the model to fit the prelaunch measured transmittance. The results reveal that the model does not reproduce the measured transmittance unless the size of the apertures in the SD screen is quite different from the design value. We attribute the difference to the orientation alignment errors for the SD panel and the measurement apparatus. We model the alignment errors and apply our transmittance model to fit the prelaunch transmittance to retrieve the "true" transmittance. To use this model correctly, we also examine the finite source size effect on the transmittance. Furthermore, we compare the product of the retrieved "true" transmittance and the prelaunch SD bidirectional reflectance distribution function (BRDF) value to the value derived from on-orbit data to determine whether the prelaunch SD BRDF value is relatively accurate. The model is significant in that it can evaluate whether the SD screen transmittance measured prelaunch is accurate and help retrieve the true transmittance from the transmittance with measurement errors, consequently resulting in a more accurate sensor data product by the same amount.

11.
Zygote ; 25(2): 160-167, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28137332

RESUMO

This study attempted to investigate and validate whether epididymis cold storage could be a suitable alternative for short-term preservation of spermatozoa. Mouse cauda epididymides and spermatozoa were preserved at 4-8°C from 1 day to 6 weeks. From days 1 to 10, motility and fertility were daily examined when motility loss occurred. From week 1, spermatozoa were used for intracytoplasmic sperm injection (ICSI) at weekly intervals to test their fertility, and spermatozoa DNA integrity was determined by comet assay. We found that motility and progressive motility scores gradually decreased with storage time. In nearly all spermatozoa, DNA integrity was maintained from days 1 to 10, but the percentage of spermatozoa with damaged DNA significantly increased from week 2 to week 6. Spermatozoa retained fertility until day 6, although fertility gradually decreased after day 3. From week 1 to week 5, fertilization rates by ICSI were more than 82.69% but decreased gradually after week 3. We found that spermatozoa preserved in the epididymis at 4-8°C had progressively lower motility, fertility and proportion of undamaged DNA, but could still fertilize oocytes. However, all the parameters of cold-preserved spermatozoa were completely inferior to that from cold-preserved cauda epididymides. The results imply that cold storage of cauda epididymides could be conducive to short-term preservation of spermatozoa, and the cold-stored spermatozoa can resist DNA denaturation, which is necessary for maintaining reproductive ability.


Assuntos
Criopreservação/métodos , DNA/química , Epididimo/fisiologia , Fertilização in vitro/veterinária , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Animais , Células Cultivadas , DNA/genética , Epididimo/citologia , Feminino , Masculino , Camundongos , Oócitos/citologia , Interações Espermatozoide-Óvulo , Espermatozoides/citologia
12.
Molecules ; 22(8)2017 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-28825643

RESUMO

Sixteen compounds were isolated from the leaves and stems of Murrayatetramera Huang. Based on the NMR and MS spectral results, the structures were determined. It was confirmed that the isolated compounds included three new compounds (9, 10 and 13) and one new natural product (8), which were identified asmurratetra A (9), murratetra B (10), murratetra C (13) and [2-(7-methoxy-2-oxochromen-8-yl)-3-methylbut-2-enyl]3-methylbut-2-enoate (8), respectively. Meanwhile, the repellent activity against Tribolium castaneum was investigated for 13 of these isolated compounds. The results showed that the tested compounds had various levels of repellent activity against T. castaneum. Among them, compounds 1 (4(15)-eudesmene-1ß,6α-diol), 11 (isoferulic acid) and 16 (2,3-dihydroxypropyl hexadecanoate) showed fair repellent activity against T. castaneum. They might be considered as potential leading compounds for the development of natural repellents.


Assuntos
Repelentes de Insetos/química , Repelentes de Insetos/farmacologia , Murraya/química , Extratos Vegetais/química , Tribolium/efeitos dos fármacos , Animais , Espectroscopia de Ressonância Magnética , Estrutura Molecular
13.
Ann Bot ; 115(1): 127-36, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25429006

RESUMO

BACKGROUND AND AIMS: Enhanced availability of photosynthates increases nitrogen (N) mineralization and nitrification in the rhizosphere via rhizodeposition from plant roots. Under heterogeneous light conditions, photosynthates supplied by exposed ramets may promote N assimilation in the rhizosphere of shaded, connected ramets. This study was conducted to test this hypothesis. METHODS: Clonal fragments of the stoloniferous herb Glechoma longituba with two successive ramets were selected. Mother ramets were subjected to full sunlight and offspring ramets were subjected to 80 % shading, and the stolon between the two successive ramets was either severed or left intact. Measurements were taken of photosynthetic and growth parameters. The turnover of available soil N was determined together with the compostion of the rhizosphere microbial community. KEY RESULTS: The microbial community composition in the rhizosphere of shaded offspring ramets was significantly altered by clonal integration. Positive effects of clonal integration were observed on NAGase activity, net soil N mineralization rate and net soil N nitrification rate. Increased leaf N and chlorophyll content as well as leaf N allocation to the photosynthetic machinery improved the photosynthetic capability of shaded offspring ramets when the stolon was left intact. Clonal integration improved the growth performance of shaded, connected offspring ramets and whole clonal fragments without any cost to the exposed mother ramets. CONCLUSIONS: Considerable differences in microbial community composition caused by clonal integration may facilitate N assimilation in the rhizosphere of shaded offspring ramets. Increased N content in the photosynthetic machinery may allow pre-acclimation to high light conditions for shaded offspring ramets, thus promoting opportunistic light capture. In accordance with the theory of the division of labour, it is suggested that clonal integration may ameliorate the carbon assimilation capacity of clonal plants, thus improving their fitness in temporally and spatially heterogeneous habitats.


Assuntos
Carbono/metabolismo , Lamiaceae/metabolismo , Nitrogênio/metabolismo , Fotossíntese , Microbiologia do Solo , Clorofila/metabolismo , Lamiaceae/genética , Luz , Nitrificação , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Rizosfera
14.
Chem Biodivers ; 12(4): 593-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25879503

RESUMO

During a screening program for new agrochemicals from Chinese medicinal herbs and local wild plants, the petroleum ether (PE) extract of Atractylodes lancea (Thunb.) rhizomes was found to possess repellent and contact activities against Tribolium castaneum adults. Bioactivity-directed chromatographic separation of PE extract on repeated silica-gel columns led to the isolation of two polyacetylenes, atractylodin and atractylodinol (1 and 2, resp.), and two lactones, atractylenolides II and III (3 and 4, resp.). The structures of the compounds were elucidated based on NMR spectra. The four isolated compounds were evaluated for their insecticidal and repellent activities against T. castaneum. Atractylodin exhibited strong contact activity against T. castaneum adults with a LD50 value of 1.83 µg/adult. Atractylodin and atractylenolide II also possessed strong repellenct activities against T. castaneum adults. After 4-h exposure, >90% repellency was achieved with atractylodin at a low concentration of 0.63 µg/cm(2) . The results indicated that atractylodin (1) and atractylenolide II (3) have a good potential as a source for natural repellents, and 1 has the potential to be developed as natural insecticide.


Assuntos
Atractylodes/química , Repelentes de Insetos/farmacologia , Inseticidas/farmacologia , Poli-Inos/química , Poli-Inos/farmacologia , Animais , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Furanos/farmacologia , Repelentes de Insetos/química , Inseticidas/química , Lactonas/farmacologia , Espectroscopia de Ressonância Magnética , Rizoma/química , Sesquiterpenos/farmacologia , Relação Estrutura-Atividade , Tribolium/efeitos dos fármacos
15.
J Insect Sci ; 152015.
Artigo em Inglês | MEDLINE | ID: mdl-26136499

RESUMO

The essential oil of Clausena anisum-olens (Blanco) Merr. showed strong contact toxicity and repellency against Lasioderma serricorne and Liposcelis bostrychophila adults. The components of the essential oil obtained by hydrodistillation were determined by gas chromatography-mass spectrometry. It was found that the main components were myristicin (36.87%), terpinolene (13.26%), p-cymene-8-ol (12.38%), and 3-carene (3.88%). Myristicin and p-cymene-8-ol were separated by silica gel column chromatography, and their molecular structures were confirmed by means of physicochemical and spectrometric analysis. Myristicin and p-cymene-8-ol showed strong contact toxicity against L. serricorne (LD50 = 18.96 and 39.68 µg per adult) and Li. bostrychophila (LD50 = 20.41 and 35.66 µg per adult). The essential oil acting against the two grain storage insects showed LD50 values of 12.44 and 74.46 µg per adult, respectively. Myristicin and p-cymene-8-ol have strong repellent toxicity to Li. bostrychophila.


Assuntos
Clausena/química , Repelentes de Insetos , Insetos , Inseticidas , Óleos Voláteis , Animais , Besouros
16.
Molecules ; 20(9): 15735-47, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26343627

RESUMO

The chemical composition of the essential oil of Etlingera yunnanensis rhizomes and its contact and repellent activities against Tribolium castaneum (Herbst) and Liposcelis bostrychophila (Badonnel) were investigated. The essential oil obtained from E. yunnanensis rhizomes with hydrodistillation was performed by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. The main components of the essential oil were identified to be estragole (65.2%), ß-caryophyllene (6.4%), 1,8-cineole (6.4%), limonene (5.2%), and α-pinene (2.4%). It was found that the essential oil of E. yunnanensis rhizomes possessed contact toxicity against T. castaneum and L. bostrychophila (LD50 = 23.33 µg/adult and LD50 = 47.38 µg/cm², respectively). Estragole, 1,8-cineole, and limonene exhibited stronger contact toxicity (LD50 values of 20.41, 18.86, and 13.40 µg/adult, respectively) than ß-caryophyllene (LD50 = 41.72 µg/adult) against T. castaneum adults. Estragole possessed stronger contact toxicity (LD50 = 30.22 µg/cm²) than ß-caryophyllene, 1,8-cineole, and limonene (LD50 values of 74.11, 321.20, and 239.62 µg/adult, respectively) against L. bostrychophila adults. Repellency of the crude oil was also evaluated. The essential oil and constituents possessed strong repellent activity against T. castaneum adults. The four individual constituents showed weaker repellent activity than the essential oil against L. bostrychophila adults. The results indicated that the essential oil of E. yunnanensis rhizomes and the individual constituents had the potential to be developed as a natural insecticide and repellent for the control of T. castaneum and L. bostrychophila.


Assuntos
Insetos/efeitos dos fármacos , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Zingiberaceae/química , Animais , Repelentes de Insetos/química , Repelentes de Insetos/farmacologia , Inseticidas/química , Inseticidas/farmacologia , Rizoma/química
17.
PLoS One ; 19(3): e0298258, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38446823

RESUMO

Clonal integration of defense or stress signal induced systemic resistance in leaf of interconnected ramets. However, similar effects of stress signal in root are poorly understood within clonal network. Clonal fragments of Centella asiaticas with first-young, second-mature, third-old and fourth-oldest ramets were used to investigate transportation or sharing of stress signal among interconnected ramets suffering from low water availability. Compared with control, oxidative stress in root of the first-young, second-mature and third-old ramets was significantly alleviated by exogenous ABA application to the fourth-oldest ramets as well as enhancement of antioxidant enzyme (SOD, POD, CAT and APX) activities and osmoregulation ability. Surface area and volume in root of the first-young ramets were significantly increased and total length in root of the third-old ramets was significantly decreased. POD activity in root of the fourth-oldest and third-old ramets was significantly enhanced by exogenous ABA application to the first-young ramets. Meanwhile, total length and surface area in root of the fourth-oldest and third-old ramets were significantly decreased. Ratio of belowground to aboveground biomass in the whole clonal fragments was significantly increased by exogenous ABA application to the fourth-oldest or first-young ramets. It is suggested that transportation or sharing of stress signal may induce systemic resistance in root of interconnected ramets. Specially, transportation or sharing of stress signal against phloem flow was observed in the experiment. Possible explanation is that rapid recovery of foliar photosynthesis in first-young ramets subjected to exogenous ABA application can partially reverse phloem flow within clonal network. Thus, our experiment provides insight into ecological implication on clonal integration of stress signal.


Assuntos
Antioxidantes , Centella , Ansiedade , Biomassa , Osmorregulação
18.
Cell Rep ; 43(2): 113694, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38265937

RESUMO

N-methyl-D-aspartate (NMDA)-type ionotropic glutamate receptors have essential roles in neurotransmission and synaptic plasticity. Previously, we identified an evolutionarily conserved protein, NRAP-1, that is required for NMDA receptor (NMDAR) function in C. elegans. Here, we demonstrate that NRAP-1 was sufficient to gate NMDARs and greatly enhanced glutamate-mediated NMDAR gating, thus conferring coincident activation properties to the NMDAR. Intriguingly, vertebrate NMDARs-and chimeric NMDARs where the amino-terminal domain (ATD) of C. elegans NMDARs was replaced by the ATD from vertebrate receptors-were spontaneously active when ectopically expressed in C. elegans neurons. Thus, the ATD is a primary determinant of NRAP-1- and glutamate-mediated gating of NMDARs. We determined the crystal structure of NRAP-1 at 1.9-Å resolution, which revealed two distinct domains positioned around a central low-density lipoprotein receptor class A domain. The NRAP-1 structure, combined with chimeric and mutational analyses, suggests a model where the three NRAP-1 domains work cooperatively to modify the gating of NMDARs.


Assuntos
Caenorhabditis elegans , Receptores de N-Metil-D-Aspartato , Animais , Receptores de N-Metil-D-Aspartato/metabolismo , Caenorhabditis elegans/metabolismo , N-Metilaspartato , Transmissão Sináptica , Ácido Glutâmico
19.
Biol Reprod ; 88(2): 51, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23255335

RESUMO

DMRT1 is an evolutionarily conserved transcriptional factor expressed only in the postnatal testis, where it is produced in Sertoli cells and germ cells. While deletion of Dmrt1 in mice demonstrated it is required for postnatal testis development and fertility, much is still unknown about its temporal- and cell-specific functions. This study characterized a novel mouse model of DMRT1-deficient germ cells that was generated by breeding Dmrt1-null (Dmrt1(-/-)) mice with Wt1-Dmrt1 transgenic (Dmrt1(+/-;tg)) mice, which express a rat Dmrt1 cDNA in gonadal supporting cells by directing it from the Wilms tumor 1 locus in a yeast artificial chromosome transgene. Like Dmrt1(-/-) mice, male Dmrt1(-/-) transgenic mice (Dmrt1(-/-;tg)) were infertile, while female mice were fertile. Immunohistochemistry and Western blot analysis showed transgenic DMRT1 expressed in supporting cells of the newborn gonads of both sex and in Sertoli cells of the testis afterbirth. Sertoli cells were evaluated by electron microscopy, revealing that maturation of Dmrt1(-/-;tg) Sertoli cells was incomplete. Morphological analysis of testes from 42-day-old mice showed that, compared to Dmrt1(-/-) mice, Dmrt1(-/-;tg) mice have improved seminiferous tubule structure, with lumens present in many. Immunohistochemistry of the polarity markers ESPIN and NECTIN-2 showed that DMRT1 in Sertoli cells is required for NECTIN-2 expression and influences organization of ectoplasmic specializations. Further functional analyses of the transgene on a Dmrt1(-/-) background showed that it did not rescue the decrease in Dmrt1(-/-) testis size, but when expressed on a wild-type background, exogenous DMRT1 prevented the normal age-related decline in testis size and enhanced sperm progressive motility. The studies suggest that DMRT1 in Sertoli cells regulates tubule morphology, spermatogenesis, and sperm function via its effects on Sertoli cell maturation and polarity. Furthermore, expression and function of transgenic DMRT1 in Sertoli cells establishes a novel mouse model of DMRT1-deficient germ cells generated by breeding Dmrt1-null mice with Wt1-Dmrt1 transgenic mice (rescue; Dmrt1(-/-;tg)).


Assuntos
Modelos Animais , Células de Sertoli/metabolismo , Testículo/metabolismo , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Transgenes/genética , Animais , Moléculas de Adesão Celular/metabolismo , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Proteínas dos Microfilamentos/metabolismo , Microscopia Eletrônica de Transmissão , Nectinas , Células de Sertoli/patologia , Células de Sertoli/ultraestrutura , Motilidade dos Espermatozoides/fisiologia , Testículo/patologia , Testículo/ultraestrutura , Fatores de Transcrição/metabolismo
20.
Toxicol In Vitro ; 91: 105613, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37182589

RESUMO

4-Vinylcyclohexene diepoxide (VCD) is a hazardous industrial material which is widely used in the production of fragrances, rubber tires, antioxidants, pesticides, flame retardants and plasticizers. Previous studies have shown that exposure to VCD damages the female reproductive system, but the effects and mechanisms of VCD exposure on human granulosa cells are not reported. In this study, we used a human granulosa cell line (SVOG) to explore the effects of VCD exposure and found that VCD exposure had toxic effects on SVOG cells in vitro. VCD exposure led to excessive accumulation of intracellular ROS, caused DNA damage in cells, altered the expression of some key genes related with apoptosis and oxidative stress, and ultimately inhibited the proliferative capacity of granulosa cells, resulting in increased apoptosis. Overall, our findings provide solid evidence showing that VCD exposure produces severe damage to human granulosa cells, which is helpful for understanding the reproductive toxicity of VCD and etiology of infertility.


Assuntos
Cicloexenos , Células da Granulosa , Humanos , Feminino , Espécies Reativas de Oxigênio , Cicloexenos/toxicidade , Compostos de Vinila/toxicidade , Apoptose , Dano ao DNA
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