microRNAs (miRNAs) are increasingly recognized as important regulators of many biological processes in mosquitoes, vectors of numerous devastating infectious diseases. Identification of bona fide ...targets remains the bottleneck for functional studies of miRNAs. In this study, we used CLEAR-CLIP assays to systematically analyze miRNA-mRNA interactions in adult female Anopheles gambiae mosquitoes. Thousands of miRNA-target pairs were captured after direct ligation of the miRNA and its cognate target transcript in endogenous Argonaute-miRNA-mRNA complexes. Using two interactions detected in this manner, miR-309-SIX4 and let-7-kr-h1, we demonstrated the reliability of this experimental approach in identifying in vivo gene regulation by miRNAs. The miRNA-mRNA interaction dataset provided an invaluable opportunity to decipher targeting rules of mosquito miRNAs. Enriched motifs in the diverse targets of each miRNA indicated that the majority of mosquito miRNAs rely on seed-based canonical target recognition, while noncanonical miRNA binding sites are widespread and often contain motifs complementary to the central or 3' ends of miRNAs. The time-lapse study of miRNA-target interactomes in adult female mosquitoes revealed dynamic miRNA regulation of gene expression in response to varying nutritional sources and physiological demands. Interestingly, some miRNAs exhibited flexibility to use distinct sequences at different stages for target recognition. Furthermore, many miRNA-mRNA interactions displayed stage-specific patterns, especially for those genes involved in metabolism, suggesting that miRNAs play critical roles in precise control of gene expression to cope with enormous physiological demands associated with egg production. The global mapping of miRNA-target interactions contributes to our understanding of miRNA targeting specificity in non-model organisms. It also provides a roadmap for additional studies focused on regulatory functions of miRNAs in Anopheles gambiae.
Ag/ZnO nanoparticles photocatalysts with various Ag concentrations were synthesized through the hydrothermal treatment. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning ...electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS), photoluminescence spectrometry (PL), electron paramagnetic resonance (EPR), and photoelectrochemical experiments. The photocatalytic performance of all samples was examined with the photodegradation experiment for methylene blue (MB) aqueous solution under simulated daylight. Photocatalytic experiment results showed 93.6%, 97.2%, 98.8%, and 99.8% photodegradation of MB, corresponding to the ZnO and the Ag/ZnO photocatalysts with various Ag concentrations. The results indicated that the photodegradation rates of all Ag/ZnO samples were better than that of ZnO. Besides, it was studied on the effects of photocatalyst dosage, pollutant concentration, and the radical oxidative species (ROS) on photocatalytic performance. Furthermore, a reasonable mechanism was proposed for the enhanced photocatalytic performance of the Ag/ZnO samples in photodegradation MB reactions.
Drastic changes in gene expression occur after adult female mosquitoes take a blood meal and use the nutrients for egg maturation. A growing body of evidence indicates that microRNAs (miRNAs) ...contribute to this tightly controlled tissue- and stage-specific gene expression. To investigate the role of miRNAs, we monitored miRNA expression in the mosquito Anopheles gambiae during the 72-h period immediately after blood feeding. We also measured the association of miRNAs with Argonaute 1 (Ago1) and Argonaute 2 (Ago2) to assess the functional status of individual miRNA species. Overall, 173 mature miRNAs were precipitated with Ago1 and Ago2, including 12 new miRNAs, the orthologs of which are found thus far only in other Anopheles species. Ago1 is the predominant carrier of miRNAs in Anopheles gambiae. The abundance and Ago loading of most of the mature miRNAs were relatively stable after blood ingestion. However, miRNAs of the miR-309/286/2944 cluster were considerably upregulated after blood feeding. Injection of the specific antagomir for miR-309 resulted in smaller developing oocytes and ultimately fewer eggs. In addition, the Ago association of some miRNAs was not proportional to their cellular abundance, suggesting that integration of miRNAs into the Ago complexes is regulated by additional mechanisms.
Malaria, caused by the protozoan parasite Plasmodium and transmitted by Anopheles mosquitoes, represents a major threat to human health. Plasmodium's infection cycle in the Anopheles vector is ...critical for transmission of the parasite between humans. The midgut-stage bottleneck of infection is largely imposed by the mosquito's innate immune system. microRNAs (miRNAs, small noncoding RNAs that bind to target RNAs to regulate gene expression) are also involved in regulating immunity and the anti-Plasmodium defense in mosquitoes. Here, we characterized the mosquito's miRNA responses to Plasmodium infection using an improved crosslinking and immunoprecipitation (CLIP) method, termed covalent ligation of endogenous Argonaute-bound RNAs (CLEAR)-CLIP. Three candidate miRNAs' influence on P. falciparum infection and midgut microbiota was studied through transgenically expressed miRNA sponges (miR-SPs) in midgut and fat body tissues. MiR-SPs mediated conditional depletion of aga-miR-14 or aga-miR-305, but not aga-miR-8, increased mosquito resistance to both P. falciparum and P. berghei infection, and enhanced the mosquitoes' antibacterial defenses. Transcriptome analysis revealed that depletion of aga-miR-14 or aga-miR-305 resulted in an increased expression of multiple immunity-related and anti-Plasmodium genes in mosquito midguts. The overall fitness cost of conditionally expressed miR-SPs was low, with only one of eight fitness parameters being adversely affected. Taken together, our results demonstrate that targeting mosquito miRNA by conditional expression of miR-SPs may have potential for the development of malaria control through genetically engineered mosquitoes.
The electrochemical activity and stability of the PBCO electrode are investigated under the annealing processes in an atmosphere containing CO2/H2O for solid oxide fuel cells (SOFCs). The ...electrochemical impedance spectrum results unequivocally confirm the significant deterioration in PBCO cathode performance upon annealing under ambient air conditions, particularly when exposed to CO2/H2O atmospheres. Microstructure and surface chemical state analyses reveal the segregation of BaO on the PBCO surface, and the formation of insulating BaCO3 degraded the electrochemical performance. CO2 and H2O exhibit a significant induced effect on the segregation of Ba in PBCO to the surfaces, thereby causing a rapid decline in electrode performance. Additionally, the analysis of volume relaxation reveals that the presence of oxygen in the electrode environment can also influence the deposition process occurring on the surface of the electrode. However, this phenomenon is not observed in N2. This study emphasizes the impact of various gases present in the working atmosphere on surface-separated BaO, which consequently plays a pivotal role in the activity and long-term stability of PBCO electrodes.
Eur J Clin Invest 2011; 41 (11): 1245–1253
Background Recent studies have shown that microRNAs (miRNA) could play a potential role as diagnostic and prognostic biomarkers of cancers. The aim of this ...meta‐analysis is to summarize the global predicting role of miR‐21 for survival in patients with a variety of carcinomas.
Design Eligible studies were identified and assessed for quality through multiple search strategies. Data were collected from studies comparing overall, relapse‐free or cancer‐specific survival (CSS) in patients with cancer having higher miR‐21 expression with those having lower levels. Pooled hazard ratios (HRs) of miR‐21 for survival were calculated.
Results A total of 17 studies dealing with various carcinomas were included for this global meta‐analysis. For overall survival (OS), the pooled hazard ratio (HR) of higher miR‐21 expression in cancerous tissue was 1·69 (95% CI: 1·33–2·16, P < 0·001), which could significantly predict poorer survival in general carcinomas. For relapse‐free or CSS, elevated miR‐21 was also a significant predictor, with a pooled HR of 1·48 (95% CI: 1·03–2·11, P = 0·033). Importantly, subgroup analysis suggested that higher expression of miR‐21 correlated with worse OS in head and neck squamous cell carcinoma (HNSCC) (HR 1·46, 95% CI: 1·13–1·87, P = 0·004) and carcinomas in digestion system (HR 1·56, 95% CI: 1·08–2·26, P = 0·018).
Conclusions Our findings suggest that miR‐21 detection has a prognostic value in patients with cancer, especially in HNSCC and digestion system cancers.
Alzheimer’s disease (AD) is characterized by the accumulation of β-amyloid (Aβ) plaques and tau neurofibrillary tangles in the brain. Although the exact details of the neuronal protective effect of ...high-intensity interval training (HIIT) on AD remain unclear, the preclinical phase of AD appears to be the important time point for such intervention. The described experiment investigates the neuroprotective effect of HIIT on AD in APP/PS1 mice. In total, 14 C57BL6 healthy control (C) mice and 14 APP/PS1 AD mice were each randomly assigned into two groups, one that did not participate in HIIT (C and AD groups, respectively) and the other subject to HIIT intervention (control HIIT (CE) and AD HIIT (ADE) groups, respectively). Visualization of hippocampal neuronal cells via HE and Congo red staining showed significant improvement in cell status and a significant reduction in amyloidosis in ADE compared with AD. The results of behavioral analysis show that the HIIT intervention significantly improved cognitive decline and reduced spatial exploration in both the C and AD groups. Immunofluorescence showed that the overall brain and the hippocampus of aged rats in the C and AD groups had different degrees of neuroglial responses and astrocyte GFAP proliferation and hypertrophy, with obvious improvement in the CE and ADE groups after 10 weeks of HIIT intervention. These results show that HIIT significantly improves the status of mitochondrial kinetic proteins and related proteins, with the mechanism differing between the normal aging C and the AD groups. 10 weeks of HIIT improved the imbalance in mitochondrial dynamics present in normal control mice and in AD mice. We conclude that preclinical training intervention has a significant positive effect on the exploratory behavior and cognitive functioning of mice.
By using the first-principles calculations based on density functional theory combined with quasi-harmonic approximation, we have studied the geometric structural, thermal properties, and the ...negative thermal expansion (NTE) properties of tetrahedral NbPO5. The variations of cell parameter and cell volume of tetrahedral NbPO5 with temperature show that it displays NTE behavior in the range of 473-800 K along a-axis and the corresponding average coefficient of thermal expansion (CTE) is approximately -0.766 ×10−6 K−1, while the c cell parameter and the cell volume display positive thermal expansion behaviors. These results are in consistent well with the experiment observations. Further vibrational modes analysis, together with Grüneisen parameters calculations, revealed that the transverse vibration of O corner atoms accompanying the rocking motions of corner-shared NbO6 octahedron and PO4 tetrahedron dominate the negative thermal properties of tetrahedral NbPO5. Our findings will provide an understanding for the underlying mechanisms of the NTE in oxides materials.
Recent studies have shown that C-reactive protein (CRP) may be associated with breast cancer. The purpose of this study is to summarize the predictive role of CRP for survival in breast cancer as ...shown in all available studies worldwide.
Related studies were identified and evaluated for quality through multiple search strategies. Data were collected from studies comparing overall, cancer-specific, and disease-free survival (OS, CSS, and DFS) in patients with elevated CRP levels and those having lower levels. Studies were pooled, and combined hazard ratios (HRs) of CRP for survival were calculated.
A total of 10 studies (n=4,502) were included for this meta-analysis (9 for OS, 3 for CSS, and 3 for DFS). For overall and disease-free survival, the pooled HRs of CRP were significant at 1.62 (95% confidence interval 95% CI, 1.20-2.18) and 1.81 (95% CI, 1.44-2.26), respectively. For cancer-specific survival, the pooled HR in higher CRP expression in breast cancer was 2.08 (95% CI, 1.48-2.94), which could strongly predict poorer survival in breast cancer.
CRP has a critical prognostic value in patients with breast cancer as an inflammation biomarker.
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