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1.
Sci Total Environ ; 921: 171098, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38387572

RESUMO

Understanding the acclimation capacity of reef corals across generations to thermal stress and its underlying molecular underpinnings could provide insights into their resilience and adaptive responses to future climate change. Here, we acclimated adult brooding coral Pocillopora damicornis to high temperature (32 °C vs. 29 °C) for three weeks and analyzed the changes in phenotypes, transcriptomes and DNA methylomes of adult corals and their brooded larvae. Results showed that although adult corals did not show noticeable bleaching after thermal exposure, they released fewer but larger larvae. Interestingly, larval cohorts from two consecutive lunar days exhibited contrasting physiological resistance to thermal stress, as evidenced by the divergent responses of area-normalized symbiont densities and photochemical efficiency to thermal stress. RNA-seq and whole-genome bisulfite sequencing revealed that adult and larval corals mounted distinct transcriptional and DNA methylation changes in response to thermal stress. Remarkably, larval transcriptomes and DNA methylomes also varied greatly among lunar days and thermal treatments, aligning well with their physiological metrics. Overall, our study shows that changes in transcriptomes and DNA methylomes in response to thermal acclimation can be highly life stage-specific. More importantly, thermally-acclimated adult corals could produce larval offspring with temporally contrasting photochemical performance and thermal resilience, and such variations in larval phenotypes are associated with differential transcriptomes and DNA methylomes, and are likely to increase the likelihood of reproductive success and plasticity of larval propagules under thermal stress.


Assuntos
Antozoários , Animais , Antozoários/genética , Transcriptoma , Epigenoma , Aclimatação/fisiologia , Mudança Climática , Larva , Recifes de Corais
2.
Mar Environ Res ; 193: 106218, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38039737

RESUMO

The co-occurrence of elevated seawater temperature and local stressors (heavy metal contamination) affects the ecophysiology of phototrophic species, and represents a risk to the environmental quality of coral reefs. Therefore, we investigated the effects of both Cu alone and Cu in combination with elevated temperature (ET) on the physiology of the coral Galaxea fascicularis, and measured the parameters related to the photo-physiology and oxidative state. G.fascicularis is one of the dominant coral species in the South China Sea which exhibits strong adaptability to environmental stress. We exposed the common coral species G.fascicularis to a series of environmentally relevant concentrations of Cu at 29 °C (normal temperature, NT) and 32 °C (elevated temperature, ET) for 96 h. Single polyps were used in the experiments, which reduced individual variability when compared to the coral colonies. The results suggested that: i) Cu or ET had significant negative effects on the actual operating ability of photosystem Ⅱ (PSII), but not on the maximal chlorophyll fluorescence in darkness (Fv/Fm). ii) Symbiodiniaceae density was significantly reduced by high Cu concentrations, for Cu-NT and Cu-ET, a high concentration of Cu (40 µg/L) significantly impacted Symbiodiniaceae density, causing a 75.4% and 81.0% decrease, respectively. iii) the content of malondialdehyde (MDA) in coral tissues increased significantly under Cu-ET. iv) a certain range of copper concentration (25-30 µg/L) increased the pigment content of the Symbiodiniacea. Our results indicated that the combined stressors of Cu and ET made the coral tissue sloughed, caused the coral tissue damaged by lipid oxidation, reduced the photosynthetic capacity of the Symbiodiniacea, and led to the excretion of Symbiodiniacea.


Assuntos
Antozoários , Animais , Antozoários/fisiologia , Cobre/toxicidade , Temperatura , Recifes de Corais
3.
Molecules ; 28(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36838786

RESUMO

The naringin extraction process was optimised using response surface methodology (RSM). A central component design was adopted, which included four parameters: extraction temperature (X1), material-liquid ratio (X2), extraction time (X3), and ultrasonic frequency (X4) of 74.79 °C, 1.58 h, 1:56.51 g/mL, and 28.05 KHz, respectively. Based on these optimal extraction conditions, naringin was tested to verify the model's accuracy. Naringin yield was 36.2502 mg/g, which was equivalent to the predicted yield of 36.0124 mg/g. DM101 macroporous adsorption resin was used to purify naringin. The effects of loading concentration, loading flow rate, and sample pH on the adsorption rate of naringin and the effect of ethanol concentration on the desorption rate of naringin were investigated. The optimum conditions for naringin purification using macroporous resins were determined. The optimal loading concentration, sample solution pH, and loading flow rate were 0.075 mg/mL, 3.5, and 1.5 mL/min, respectively. Three parallel tests were conducted under these conditions, and the average naringin yield was 77.5643%. Naringin's structure was identified using infrared spectroscopy and nuclear magnetic resonance. In vitro determination of the lipid-lowering activity of naringin was also conducted. These results showed that naringin has potential applications as a functional food for lowering blood lipid levels.


Assuntos
Flavanonas , Ultrassom , Extratos Vegetais/química , Temperatura
4.
Mol Ecol ; 32(5): 1098-1116, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36528869

RESUMO

Thermal priming of reef corals can enhance their heat tolerance; however, the legacy effects of heat stress during parental brooding on larval resilience remain understudied. This study investigated whether preconditioning adult coral Pocillopora damicornis to high temperatures (29°C and 32°C) could better prepare their larvae for heat stress. Results showed that heat-acclimated adults brooded larvae with reduced symbiont density and shifted thermal performance curves. Reciprocal transplant experiments demonstrated higher bleaching resistance and better photosynthetic and autotrophic performance in heat-exposed larvae from acclimated adults compared to unacclimated adults. RNA-seq revealed strong cellular stress responses in larvae from heat-acclimated adults that could have been effective in rescuing host cells from stress, as evidenced by the widespread upregulation of genes involved in cell cycle and mitosis. For symbionts, a molecular coordination between light harvesting, photoprotection and carbon fixation was detected in larvae from heat-acclimated adults, which may help optimize photosynthetic activity and yield under high temperature. Furthermore, heat acclimation led to opposing regulations of symbiont catabolic and anabolic pathways and favoured nutrient translocation to the host and thus a functional symbiosis. Notwithstanding, the improved heat tolerance was paralleled by reduced light-enhanced dark respiration, indicating metabolic depression for energy saving. Our findings suggest that adult heat acclimation can rapidly shift thermal tolerance of brooded coral larvae and provide integrated physiological and molecular evidence for this adaptive plasticity, which could increase climate resilience. However, the metabolic depression may be maladaptive for long-term organismal performance, highlighting the importance of curbing carbon emissions to better protect corals.


Assuntos
Antozoários , Termotolerância , Animais , Antozoários/genética , Recifes de Corais , Larva , Termotolerância/genética , Aclimatação , Simbiose
5.
Sci Total Environ ; 842: 156851, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35750167

RESUMO

The successful dispersal of coral larvae is vital to the population replenishment and reef recovery and resilience. Despite that this critical early stage is susceptible to ocean warming and acidification, little is known about the responses of coral larvae to warming and acidification across different biological scales. This study explored the influences of elevated temperature (29 °C versus 33 °C) and pCO2 (500 µatm versus 1000 µatm) on brooded larvae of Pocillopora damicornis at the organismal, cellular and gene expression levels. Heat stress caused bleaching, depressed light-enhanced dark respiration, photosynthesis and autotrophy, whereas high pCO2 stimulated photosynthesis. Although survival was unaffected, larvae at 33 °C were ten-times more likely to settle than those at 29 °C, suggesting reduced capacity to disperse and differentiate suitable substrate. Remarkably, heat stress induced greater symbiont loss at ambient pCO2 than at high pCO2, while cell-specific pigment concentrations of symbionts at 33 °C increased twofold under ambient pCO2 relative to high pCO2, suggesting pCO2-dependent bleaching patterns. Considerable increases in activities of host antioxidants superoxide dismutase (SOD) and catalase (CAT) at 33 °C indicated oxidative stress, whereas lipid peroxidation and caspase activities were contained, thereby restraining larval mortality at 33 °C. Furthermore, the coral host mounted stronger transcriptional responses than symbionts. High pCO2 stimulated host metabolic pathways, possibly because of the boosted algal productivity. In contrast, host metabolic processes and symbiont photosystem genes were downregulated at 33 °C. Interestingly, the upregulation of extracellular matrix genes and glycosaminoglycan degradation pathway at 33 °C was more evident under ambient pCO2 than high pCO2, suggesting compromised host tissue integrity that could have facilitated symbiont expulsion and bleaching. Our results provide insights into how coral larvae respond to warming and acidification at different levels of biological organization, and demonstrate that ocean acidification can mediate thermal bleaching and gene expression in coral larvae under heat stress.


Assuntos
Antozoários , Animais , Antozoários/fisiologia , Recifes de Corais , Expressão Gênica , Resposta ao Choque Térmico , Concentração de Íons de Hidrogênio , Larva , Oceanos e Mares , Água do Mar
6.
Mol Biol Rep ; 49(4): 3055-3064, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35032258

RESUMO

BACKGROUND: Although osteosarcoma (OS) is the most common malignant bone tumor, the biological mechanism underlying its incidence and improvement remains unclear. This study investigated early diagnosis and treatment objectives using bioinformatics strategies and performed experimental verification. METHODS AND RESULTS: The top 10 OS hub genes-CCNA2, CCNB1, AURKA, TRIP13, RFC4, DLGAP5, NDC80, CDC20, CDK1, and KIF20A-were screened using bioinformatics methods. TRIP13 was chosen for validation after reviewing literature. TRIP13 was shown to be substantially expressed in OS tissues and cells, according to Western blotting (WB) and quantitative real-time polymerase chain reaction data. Subsequently, TRIP13 knockdown enhanced apoptosis and decreased proliferation, migration, and invasion in U2OS cells, as validated by the cell counting kit-8 test, Hoechst 33,258 staining, wound healing assay, and WB. In addition, the levels of p-PI3K/PI3K and p-AKT/AKT in U2OS cells markedly decreased after TRIP13 knockdown. Culturing U2OS cells, in which TRIP13 expression was downregulated, in a medium supplemented with a PI3K/AKT inhibitor further reduced their proliferation, migration, and invasion and increased their apoptosis. CONCLUSIONS: TRIP13 knockdown reduced U2OS cell proliferation, migration, and invasion via a possible mechanism involving the PI3K/AKT signaling pathway.


Assuntos
Neoplasias Ósseas , Proteínas de Ciclo Celular , Osteossarcoma , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Apoptose/genética , Neoplasias Ósseas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Humanos , Osteossarcoma/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genética
7.
Ecol Evol ; 12(12): e9677, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36619709

RESUMO

Allopolyploids are believed to inherit the genetic characteristics of its progenitors and exhibit stronger adaptability and vigor. The allotetraploid Isoetes sinensis was formed by the natural hybridization and polyploidization of two diploid progenitors, Isoetes taiwanensis and Isoetes yunguiensis, and was believed to have the potential to adapt to plateau environments. To explore the expression pattern of homoeologous genes and their contributions to altitude adaptation, we transplanted natural allotetraploid I. sinensis (TnTnYnYn) along the altitude gradient for a long-term, and harvested them in summer and winter, respectively. One year after transplanting, it still lived well, even in the extreme environment of the Qinghai-Tibet Plateau. Then, we performed high-throughput RNA sequencing to measure their gene expression level. A total of 7801 homoeologous genes were expressed, among which 5786 were identified as shared expression in different altitudes and seasons. We further found that altitude variations could change the subgenome bias trend of I. sinensis, but season could not. Moreover, the functions of uniquely expressed genes indicated that temperature might be an important restrictive factor during the adaptation process. Through the analysis of DEGs and uniquely expressed genes, we found that Y subgenome provided more contributions to high altitude adaptation than T subgenome. These adaptive traits to high altitude may be inherited from its plateau progenitor I. yunguiensis. Through weighted gene co-expression network analysis, pentatricopeptide repeats gene family and glycerophospholipid metabolism pathway were considered to play important roles in high-altitude adaptation. Totally, this study will enrich our understanding of allopolyploid in environmental adaptation.

8.
Sci Rep ; 11(1): 11165, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045512

RESUMO

The spindle and kinetochore-associated protein complex (Ska) is an essential component in chromosome segregation. It comprises three proteins (Ska1, Ska2, and Ska3) with theorized roles in chromosomal instability and tumor development, and its overexpression has been widely reported in a variety of tumors. However, the prognostic significance and immune infiltration of Ska proteins in hepatocellular carcinoma (HCC) are not completely understood. The bioinformatics tools Oncomine, UALCAN, gene expression profiling interactive analysis 2 (GEPIA2), cBioPortal, GeneMANIA, Metascape, and TIMER were used to analyze differential expression, prognostic value, genetic alteration, and immune cell infiltration of the Ska protein complex in HCC patients. We found that the mRNA expression of the Ska complex was markedly upregulated in HCC. High expression of the Ska complex is closely correlated with tumor stage, patient race, tumor grade, and TP53 mutation status. In addition, high expression of the Ska complex was significantly correlated with poor disease-free survival, while the high expression levels of Ska1 and Ska3 were associated with shorter overall survival. The biological functions of the Ska complex in HCC primarily involve the amplification of signals from kinetochores, the mitotic spindle, and (via a MAD2 invasive signal) unattached kinetochores. Furthermore, the expression of the complex was positively correlated with tumor-infiltrating cells. These results may provide new insights into the development of immunotherapeutic targets and prognostic biomarkers for HCC.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Proteínas de Ciclo Celular/genética , Proteínas Cromossômicas não Histona/genética , Cinetocoros/metabolismo , Neoplasias Hepáticas/genética , Proteínas Associadas aos Microtúbulos/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Proteínas de Ciclo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Proteínas Associadas aos Microtúbulos/metabolismo , Prognóstico , Fuso Acromático , Taxa de Sobrevida
9.
Acupunct Med ; 37(4): 252-258, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31342771

RESUMO

BACKGROUND: Acupuncture stimulation at GV26 during the acute phase of cerebral ischaemia can effectively reduce brain damage induced by ischaemic injury. However, the time course of the effects of acupuncture stimulation has not yet been thoroughly studied. OBJECTIVE: To investigate the effects of manual acupuncture (MA) on glutamic acid (Glu) and γ-aminobutyric acid (GABA) expression in the cerebrospinal fluid of rats with middle cerebral artery occlusion (MCAO) and determine whether there is a temporal effect of acupuncture on the treatment of cerebral ischaemia. METHODS: We performed thread occlusion of the right middle cerebral artery in rats to establish an animal model of MCAO. Simultaneously, during acupuncture treatment, microdialysis was used to continuously and dynamically observe immediate alterations in amino acid metabolism with acupuncture stimulation after cerebral ischaemia in vivo in this rat model of MCAO. RESULTS: We found that, in comparison with an untreated MCAO group, Glu content was significantly decreased during the first acupuncture stimulation and during the course of the acupuncture treatment in the MCAO+MA group (MCAO vs MCAO+MA: day 1, P=0.032; day 2, P=0.021; day 3, P=0.017). These findings were also seen after the end of treatment when acupuncture was no longer applied (MCAO vs MCAO+MA: day 7, P=0.009). Measurements of GABA content following cerebral ischaemic injury showed that GABA peaks 24 hours after damage, falls thereafter and decreases to baseline levels on day 7. In the MCAO+MA group, GABA content on days 1 to day 2 was lower than in the MCAO group (MCAO+MA vs MCAO: day 1, P=0.003; day 2, P=0.001), although it was higher than in the control group (MCAO+MA vs control: day 1, P=0.024; day 2, P=0.009). GABA content on day 3 and day 7 was higher in the MCAO+MA group than in the MCAO group and the control group (MCAO+MA vs MCAO: day 3, P=0.008; day 7, P=0.013; MCAO+MA vs control: day 3, P=0.002; day 7, P=0.009). CONCLUSION: Acupuncture stimulation at GV26 can effectively decrease excessive release of Glu induced by ischaemia and maintain the endogenous inhibitory activity of GABA. This phenomenon was seen during the entire course of acupuncture treatment and continued for some time after the end of acupuncture treatment.


Assuntos
Terapia por Acupuntura , Isquemia Encefálica/terapia , Ácido Glutâmico/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Isquemia Encefálica/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Humanos , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/terapia , Masculino , Neurotransmissores/metabolismo , Ratos , Ratos Sprague-Dawley
10.
Anal Chem ; 86(23): 11649-56, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25381866

RESUMO

Axons are very sensitive to molecular gradients and can discriminate extremely small differences in gradient steepness. Microfluidic devices capable of generating chemical gradients and adjusting their steepness could be used to quantify the sensitivity of axonal response. Here, we present a versatile and robust microfluidic device that can generate substrate-bound molecular gradients with evenly varying steepness on a single chip to precisely quantify axonal response. In this device, two solutions are perfused into a central channel via two inlets while partially flowing into two peripheral channels through interconnecting grooves, which gradually decrease the fluid velocity along the central channel. Molecular gradients with evenly and gradually decreased steepness can therefore be generated with a high resolution that is less than 0.05%/mm. In addition, the overall distribution range and resolution of the gradient steepness can be highly and flexibly controlled by adjusting various parameters of the device. Using this device, we quantified the hippocampal axonal response to substrate-bound laminin and ephrin-A5 gradients with varying steepnesses. Our results provided more detailed information on how and to what extent different steepnesses guide hippocampal neuron development during the initial outgrowth. Furthermore, our results show that axons can sensitively respond to very shallow laminin and ephrin-A5 gradients, which could effectively initiate biased differentiation of hippocampal neurons in the steepness range investigated in this study.


Assuntos
Axônios/efeitos dos fármacos , Axônios/fisiologia , Efrina-A5/farmacologia , Laminina/farmacologia , Técnicas Analíticas Microfluídicas , Diferenciação Celular/efeitos dos fármacos , Hipocampo/citologia , Humanos
11.
Electrophoresis ; 32(23): 3371-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22058049

RESUMO

We present a feasible dielectrophoresis (DEP) approach for rapid patterning of microparticles on a reusable double-layer electrode substrate in microfluidics. Simulation analysis demonstrated that the DEP force was dramatically enhanced by the induced electric field on top interdigitated electrodes. By adjusting electric field intensity through the bottom electrodes on thin glass substrate (100 µm), polystyrene particles (10 µm) were effectively patterned by top electrodes within several seconds (<5 s). The particle average velocity can reach a maximum value of about 20.0±3.0 µm/s at 1 MHz with the strongest DEP force of 1.68 pN. This approach implements integration of functional electrodes into one substrate and avoids direct electrical connection to biological objects, providing a potential lab-on-chip system for biological applications.


Assuntos
Eletroforese/métodos , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Microesferas , Eletrodos , Eletroforese/instrumentação , Desenho de Equipamento , Vidro , Células HeLa , Humanos , Tamanho da Partícula , Poliestirenos/química , Análise Serial de Tecidos/instrumentação
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(3): 770-3, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20496706

RESUMO

An innovative technology of spectral navigation is presented in the present paper. This new method adopts reflectance spectra of fruits, leaves and branches as one of the key navigation parameters and positions the fruits of fruit trees relying on the diversity of spectral characteristics. The research results show that the distinct smoothness as effect is available in the spectrum of leaves of fruit trees. On the other hand, gradual increasing as the trend is an important feature in the spectrum of branches of fruit trees while the spectrum of fruit fluctuates. In addition, the peak diversity of reflectance rate between fruits and leaves of fruit trees is reached at 850 nm of wavelength. So the limit value can be designed at this wavelength in order to distinguish fruits and leaves. The method introduced here can not only quickly distinguish fruits, leaves and branches, but also avoid the effects of surroundings. Compared with the traditional navigation systems based on machine vision, there are still some special and unique features in the field of positioning the fruits of fruit trees using spectral navigation technology.


Assuntos
Frutas , Árvores , Folhas de Planta , Análise Espacial , Análise Espectral
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(12): 2056-60, 2005 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-16544505

RESUMO

The analysis technique of fluorescence is adopted to study the intensity of excitation fluorescence of blood in the present paper. The theoretical analysis and differences of normal and abnormal blood (hyperglycemia, hyperlipemia) are presented. The theoretical analysis was proved by experiment results. It was discovered that blood sugar consistency has an effect on blood fluorescence. In other words, with the same excitation wavelength and with blood sugar consistency increasing, the fluorescence intensity increases gradually. It is obvious that blood sugar is also a kind of fluorescein, and its consistency has an effect on fluorescence intensity, which is identical with the theoretical analysis, indicating that the experiment is successful, and it is possible to distinguish blood sugar consistency by comparing the fluorescence intensity in blood. It was also discovered that the higher the cholesterin content, the more intense the fluorescence. When excitation wavelength is especially 435 nm, the phenomenon is very obvious. The study paves a new way for the blood quick check and diagnosis of diseases.


Assuntos
Análise Química do Sangue/métodos , Glicemia/análise , Espectrometria de Fluorescência/métodos , Humanos
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