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71.
Background: Clinical studies and genetic analyses have revealed that juvenile myelomonocytic leukemia (JMML) is caused by somatic and/or germline mutations of genes involved in the RAS/MAPK signalling pathway. Given the vastly different clinical prognosis among individual patients that have had this disease, mutations in genes of other pathways may be involved. Methods: In this study, we conducted whole-exome and cancer-panel sequencing analyses on a bone marrow sample from a 2-year old juvenile myelomonocytic leukemia patient. We also measured the microRNA profile of the same patient’s bone marrow sample and the results were compared with the normal mature monocytic cells from the pooled peripheral blood. Results: We identified additional novel mutations in the PI3K/AKT pathway and verified with a cancer panel targeted sequencing. We have confirmed the previously tested PTPN11 gene mutation (exon 3 181G>T) in the same sample and identified new nonsynonymous mutations in NTRK1, HMGA2, MLH3, MYH9 and AKT1 genes. Many of the microRNAs found to be differentially expressed are known to act as oncogenic MicroRNAs (onco-MicroRNAs or oncomiRs), whose target genes are enriched in the PI3K/AKT signalling pathway. Conclusions: Our study suggests an alternative mechanism for JMML pathogenesis in addition to RAS/MAPK pathway. This discovery may provide new genetic markers for diagnosis and new therapeutic targets for JMML patients in the future.  相似文献   
72.
We assessed the indigenous arbuscular mycorrhizal fungi (AMF) community structure from the roots and associated soil of Plantago major (plantain) plants growing on sites polluted with trace metals (TM) and on unpolluted sites. Uncontaminated and TM-contaminated sites containing As, Cd, Cu, Pb, Sn and Zn were selected based on a survey of the TM concentration in soils of community gardens in the City of Montréal. Total genomic DNA was extracted directly from these samples. PCR followed by denaturing gradient gel electrophoresis (PCR-DGGE), augmented by cloning and sequencing, as well as direct sequencing techniques, was all used to investigate AMF community structure. We found a decreased diversity of native AMF (assessed by the number of AMF ribotypes) in soils and plant roots harvested from TM-polluted soils compared with unpolluted soils. We also found that community structure was modified by TM contamination. Various species of Glomus, Scutellospora aurigloba and S. calospora were the most abundant ribotypes detected in unpolluted soil; ribotypes of G. etunicatum, G. irregulare/G. intraradices and G. viscosum were found in both polluted and unpolluted soils, while ribotypes of G. mosseae and Glomus spp. (B9 and B13) were dominant in TM-polluted soils. The predominance of G. mosseae in metal-polluted sites suggests the tolerance of this species to TM stress, as well as its potential use for phytoremediation. These data are relevant for our understanding of how AMF microbial communities respond to natural environments that contain a broad variety of toxic inorganic compounds and will substantially expand our knowledge of AMF ecology and biodiversity.  相似文献   
73.
Summary The antibacterial effect of negapillin in combination with other antibiotics and sulfa drugs was studied using Gram+ve and Gram-ve bacteria as test organisms. Subsequently, various proportions of negapillin in combination with the antibiotics and the sulfa drugs were examined to determine the optimum proportions which exert maximum inhibitory effects on the bacterial growth. Mixtures of these antibiotics with negapillin were found more superior not only as antimicrobial agents but also for having comparatively low toxicity.  相似文献   
74.
75.
Annual variations in plasma testosterone and cortisol levels were determined in male wild rabbits caught monthly in their natural biotope (Zembra island). For comparison, a group of warrens was hold in semi-captivity close to Tunis. In both conditions plasma testosterone concentrations were low from January to September and peak values were observed in October. Captive warrens exhibited a clear cut annual rhythm in plasma cortisol levels also and ether stress resulted in a very large increase of cortisolemia. In rabbits caught in ther habitat however, cortisol concentrations were always extremely high throughout the year, probably due to stressing conditions. Interestingly, wild rabbits of Zembra island appear to subsist from a very remote past without any contact with other strains. As to Zembra, it is a hardly get-at-able, uninhabited island which is a part of a strictly protected natural reserve and constitutes a fairly useful and valuable ecosystem.  相似文献   
76.
Differences in the composition and amount of proteins synthesized in the cell culture and leaves of field plants Serratula coronata have been shown. They proceed from differences in intensity of synthesis of secondary metabolites, ecdysteroids, whose content in the cell culture is considerably lower.  相似文献   
77.
Ecological restoration is considered to play an important role in mitigating climate change, protecting biodiversity, and preventing environmental degradation. Yet, there are often multiple perspectives on what outcomes restoration should be aiming to achieve, and how we should get to that point. In this study we interview a range of policymakers, academics, and non‐governmental organization (NGO) representatives to explore the range of perspectives on the restoration of Indonesia's tropical peatlands—key global ecosystems that have undergone large‐scale degradation. Thematic analysis suggests that participants agreed about the importance of restoration, but had differing opinions on how effective restoration activities to date have been and what a restored peatland landscape should look like. These results exemplify how ecological restoration can mean different things to different people, but also highlight important areas of consensus for moving forward with peatland restoration strategies.  相似文献   
78.
International Journal of Peptide Research and Therapeutics - The original version of the article unfortunately contained a typo in co-author name.  相似文献   
79.

Objectives

Gold nanoparticles (AuNPs) of 21 nm have been previously well characterized in vitro for their capacity to target macrophages via active uptake. However, the short-term impact of such AuNPs on physiological systems, in particular resident macrophages located in fat tissue in vivo, is largely unknown. This project investigated the distribution, organ toxicity and changes in inflammatory cytokines within the adipose tissue after mice were exposed to AuNPs.

Methods

Male C57BL/6 mice were injected intraperitoneally (IP) with a single dose of AuNPs (7.85 μg AuNPs/g). Body weight and energy intake were recorded daily. Tissues were collected at 1 h, 24 h and 72 h post-injection to test for organ toxicity. AuNP distribution was examined using electron microscopy. Proinflammatory cytokine expression and macrophage number within the abdominal fat pad were determined using real-time PCR.

Results

At 72 hours post AuNP injection, daily energy intake and body weight were found to be similar between Control and AuNP treated mice. However, fat mass was significantly smaller in AuNP-treated mice. Following IP injection, AuNPs rapidly accumulated within the abdominal fat tissue and some were seen in the liver. A reduction in TNFα and IL-6 mRNA levels in the fat were observed from 1 h to 72 h post AuNP injection, with no observable changes in macrophage number. There was no detectable toxicity to vital organs (liver and kidney).

Conclusion

Our 21 nm spherical AuNPs caused no measurable organ or cell toxicity in mice, but were correlated with significant fat loss and inhibition of inflammatory effects. With the growing incidence of obesity and obesity-related diseases, our findings offer a new avenue for the potential development of gold nanoparticles as a therapeutic agent in the treatment of such disorders.  相似文献   
80.
The initial microorganism adhesion on substrate is an important step for the biofilm formation. The surface properties of the stainless steel and B. cereus were characterized by the sessile drop technique. Moreover, the physicochemical properties of surface adhesion and the impact of bio adhesion to the stainless steel were determined at different time of contact (2, 4, 7, 9 and 24 h). The results showed that the strain was hydrophilic (Giwi = 3.37 mJ/m2), whereas the substratum has hydrophobic character (Giwi = ?57.6 mJ/m2). Stainless steel surface presents a weak electron-donor character (γ? = 4.1 mJ/m2) conversely to B. cereus that presents an important parameter (γ? = 31.6 mJ/m2). The bio adhesion was investigated at different time of contact. The data analysis after 2 h, confirmed the adhesion of B. cereus with an amount of 10 cfu/cm2 which increased to 1.2104 cfu/cm2 after 24 h. Interestingly, despite the difference of hydropohbicity, the interaction between B. cereus and substratum was favored by the thermodynamic aspect of adhesion (ΔGadhesion < 0). Interestingly, the study of the effect of B. cereus adhesion on the stainless steel has revealed that, the substratum becomes hydrophilic (θ° = 41.3, ΔGiwi = 39.6 mJ/m2) and highly electron donor (Γ? = 52.9 mJ/m2) after 2 h of bio adhesion.  相似文献   
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