The interaction between the Wnt/β-catenin signaling cascade and PKG activation in cancer

The activation of the Wnt/β-catenin signaling cascade has been well studied and documented in colorectal cancer（CRC）.The long-term use of non-steroidal anti-inflammatory drugs（NSAIDs） has been shown to reduce the incidence and risk of death from CRC in numerous epidemiological studies.The NSA1 D sulindac has also been reported to cause regression of precancerous adenomas in individuals with familial adenomatous polyposis who are at high risk of developing CRC.The mechanism responsible for cancer chemopreventive activity of NSAIDs is not well understood but may be unrelated to their cyclooxygenase inhibitory activity.Emerging evidence suggests that sulindac inhibits the growth of colon tumor cells by suppressing the activity of certain phosphodiesterase isozymes to activate cGMβ-dependent protein kinase,PKG,through the elevation of the second messenger cyclic guanosine monophosphote,cGMP.PKG activation has been shown to inhibit the nuclear translocation of β-catenin,reduce β-catenin mRNA and protein levels,and suppress the transcriptional activity of β-catenin.This review describes the relationship between the Wnt/β-catenin signaling cascade and the activation of PKG through PDE inhibition and elevation of intracellular cGMP levels.

Inhibition of cerebral ischemia/reperfusion injuryinduced apoptosis:nicotiflorin and JAK2/STAT3 pathway

Nicotiflorin is a flavonoid extracted from Carthamus tinctorius.Previous studies have shown its cerebral protective effect,but the mechanism is undefined.In this study,we aimed to determine whether nicotiflorin protects against cerebral ischemia/reperfusion injury-induced apoptosis through the JAK2/STAT3 pathway.The cerebral ischemia/reperfusion injury model was established by middle cerebral artery occlusion/reperfusion.Nicotiflorin（10 mg/kg） was administered by tail vein injection.Cell apoptosis in the ischemic cerebral cortex was examined by hematoxylin-eosin staining and terminal deoxynucleotidyl transferase d UTP nick end labeling assay.Bcl-2 and Bax expression levels in ischemic cerebral cortex were examined by immunohistochemial staining.Additionally,p-JAK2,p-STAT3,Bcl-2,Bax,and caspase-3 levels in ischemic cerebral cortex were examined by western blot assay.Nicotiflorin altered the shape and structure of injured neurons,decreased the number of apoptotic cells,down-regulates expression of p-JAK2,p-STAT3,caspase-3,and Bax,decreased Bax immunoredactivity,and increased Bcl-2 protein expression and immunoreactivity.These results suggest that nicotiflorin protects against cerebral ischemia/reperfusion injury-induced apoptosis via the JAK2/STAT3 pathway.

Sulindac sulfide selectively increases sensitivity of ABCC1 expressing tumor cells to doxorubicin and glutathione depletion

ATP-binding cassette（ABC） transporters ABCC1（MRP1）,ABCB1（P-gp）,and ABCG2（BCRP） contribute to chemotherapy failure.The primary goals of this study were to characterize the efficacy and mechanism of the nonsteroidal anti-inflammatory drug（NSAID）,sulindac sulfide,to reverse ABCC1 mediated resistance to chemotherapeutic drugs and to determine if sulindac sulfide can influence sensitivity to chemotherapeutic drugs independently of drug efflux.Cytotoxicity assays were performed to measure resistance of ABC-expressing cell lines to doxorubicin and other chemotherapeutic drugs.NSAIDs were tested for the ability to restore sensitivity to resistance selected tumor cell lines,as well as a large panel of standard tumor cell lines.Other experiments characterized the mechanism by which sulindac sulfide inhibits ABCC1 substrate and co-substrate（GSH） transport in isolated membrane vesicles and intact cells.Selective reversal of multi-drug resistance（MDR）,decreased efflux of doxorubicin,and fluorescent substrates were demonstrated by sulindac sulfide and a related NSAID,indomethacin,in resistance selected and engineered cell lines expressing ABCC 1,but not ABCB 1 or ABCG2.Sulindac sulfide also inhibited transport of leukotriene C_4 into membrane vesicles.Sulindac sulfide enhanced the sensitivity to doxorubicin in 24 of 47 tumor cell lines,including all melanoma lines tested（7-7）.Sulindac sulfide also decreased intracellular GSH in ABCC1 expressing cells,while the glutathione synthesis inhibitor,BSO,selectively increased sensitivity to sulindac sulfide induced cytotoxicity.Sulindac sulfide potently and selectively reverses ABCC1-mediated MDR at clinically achievable concentrations.ABCC1 expressing tumors may be highly sensitive to the direct cytotoxicity of sulindac sulfide,and in combination with chemotherapeutic drugs that induce oxidative stress.

RNA Extraction from Herba Violae Roots with Low-temperature Sectioning Method

[ Objective ] This study aimed to investigate the optimal method for extracting RNA from roots of medicinal plant herba violae by comparing the effects of liquid nitrogen grinding method and low-temperature sectioning method on RNA extraction. [ Method] Roots of herba violae were respectively crushed by using liquid nitrogen grinding method and low-temperature sectioning method to extract RNA. The extraction effects of these two methods were compared based on detec- tion of RNA concentration, purity and integrity and amplification of GAPDH gene by RT-PCR. [Result] The concentration of RNA extracted by liquid nitrogen grinding method and low-temperature sectioning method was 1.21 and 3.57 p^g/~, respectively. Both RNA extracted by these two methods showed two distinct bands after agarose gel electrophoresis. The ratio of brightness of the 28S rRNA to the 18S rRNA bands was greater than 1. PCR amplification showed that the length of GAPDH gene was about 230 bp, which was consistent with the expected result. [ Conclusion ] The experimental results indicated that using low-tempera ture sectioning method to crush the roots of herba violae can meet the needs of most molecular biological experiments including gene cloning and expression analysis, which is an effective and simple method for extracting RNA from plant roots.

Identification and functional analysis of miRNAs in developing kernels of a viviparous mutant in maize

Given the important roles of miRNAs in post-transcriptional gene regulation, identification of differentially expressed miRNAs will facilitate the elucidation of molecular mechanisms underlying kernel development. In this study, we constructed a small RNA library to comprehensively represent the full complement of individual small RNAs and to characterize miRNA expression profiles in pooled ears of maize(Zea mays L.) at 10, 15,20, 22, 25 and 30 days after pollination(DAP). At least 21 miRNAs were differentially expressed. The differential expression of three of these miRNAs, i.e., miR528a, miR167a and miR160b, at each stage was verified by qRT-PCR. The results indicated that these miRNAs might be involved in kernel development. In addition, the predicted functions of target genes indicated that most of the target genes are involved in signal transduction and cell communication pathways, particularly the auxin signaling pathway. The expression of candidate germination-associated miRNAs was analyzed by hybridization to a maize genome microarray, and revealed differential expression of genes involved in plant hormone signaling pathways. This finding suggests that phytohormones play a critical role in the development of maize kernels. We found that in combination with other miRNAs, miR528a regulated a putative laccase, a Ring-H2 zinc finger protein and a MADS box-like protein, whereas miR167a and miR160b regulated multiple target genes,including ARF(auxin response factor), a member of the B3 transcription factor family. All three miRNAs are important for ear germination, development and physiology. The small RNA transcriptomes and mRNA obtained in this study will help us gain a betterunderstanding of the expression and function of small RNAs in the development of maize kernel.

Targeting plasminogen activator inhibitor-1 to prevent vascular disease

Plasminogen activator inhibitor-1(PAI-1)is the primary inhibitor of urinary-type and tissue-type plasmino-gen activators and a key regulator of fibrinolysis.PAI-1 also regulates the function of vascular cells,includingvascular smooth muscle cells(VSMCs).

Role of PAI-1 in adipose tissue senescence and inflammation in obesity

Plasminogen activator inhibitor-1(PAI-1)is a member of the evolutionarily conserved serine pro⁃tease inhibitor family.The increased expression of PAI-1 leads to pathological diseases such as vascular diseases,obesity,and metabolic syndrome.Senescence-associated secretory phenotype(SASP)mediates tissue damage and plays a role in adipose tissue dysfunction.Chronic inflammation in adipose tissue is associated with the development of metabolic diseases,including obesity,insulin resistance,and type 2 diabetes.PAI-1 plays a vital role in adipose tissue physiology,glucose metabolism,insulin secretion and sensitivity,inflammation,and macrophage chemotaxis.This article reviews the possible role of PAI-1,as one of the SASP markers,and speculates the potential role of PAI-1 in adipose tissue senescence and inflammatory macrophage infiltration in obesity.

Transferable,highly crystalline covellite membrane for multifunctional thermoelectric systems

Emerging freestanding membrane technologies,especially using inorganic thermoelectric materials,demonstrate the potential for advanced thermoelectric platforms.However,using rare and toxic elements during material processing must be circumvented.Herein,we present a scalable method for synthesizing highly crystalline CuS membranes for thermoelectric applications.By sulfurizing crystalline Cu,we produce a highly percolated and easily transferable network of submicron CuS rods.The CuS membrane effectively separates thermal and electrical properties to achieve a power factor of 0.50 mW m^(-1) K^(-2) and thermal conductivity of 0.37 W m^(-1) K^(-1) at 650 K(estimated value).This yields a record-high dimensionless figure-of-merit of 0.91 at 650 K(estimated value)for covellite.Moreover,integrating 12 CuS devices into a module resulted in a power generation of4μW atΔT of 40 K despite using a straightforward configuration with only p-type CuS.Furthermore,based on the temperature-dependent electrical characteristics of CuS,we develop a wearable temperature sensor with antibacterial properties.

Gut microbiome colonization and development in neonatal ruminants: Strategies, prospects, and opportunities

Colonization and development of the gut microbiome is a crucial consideration for optimizing the health and performance of livestock animals. This is mainly attributed to the fact that dietary and management practices greatly influence the gut microbiota, subsequently leading to changes in nutrient utilization and immune response. A favorable microbiome can be implanted through dietary or management in-terventions of livestock animals, especially during early life. In this review, we explore all the possible factors (for example gestation, colostrum, and milk feeding, drinking water, starter feed, inoculation from healthy animals, prebiotics/probiotics, weaning time, essential oil and transgenesis), which can influence rumen microbiome colonization and development. We discuss the advantages and disadvantages of potential strategies used to manipulate gut development and microbial colonization to improve the production and health of newborn calves at an early age when they are most susceptible to enteric disease. Moreover, we provide insights into possible interventions and their potential effects on rumen development and microbiota establishment. Prospects of latest techniques like transgenesis and host genetics have also been discussed regarding their potential role in modulation of rumen microbiome and subsequent effects on gut development and performance in neonatal ruminants.

A secreted phospholipase A_(2) (BmsPLA_(2)) regulates melanization of immunity through BmDDC in the silkworm Bombyx mori

Insect immune-associated phospholipase A_(2) (PLA_(2)) is an important target of pathogen invasion. Melanization, an effective defense response, has significant correlations with other immune responses to coordinate immune attack against invaders. However, the effect of PLA_(2) on melanization has not yet been reported in insects or other arthropods. In this work, we cloned a PLA_(2) gene (BmsPLA_(2)), and its protein had characteristic features of secreted PLA_(2) (sPLA_(2)). After injection of bacteria, BmsPLA_(2) expression and sPLA_(2) activity in hemolymph significantly increased. BmsPLA_(2) fluorescence was transferred from the cytoplasm to the cell membranes of circulating hemocytes. These results indicated that BmsPLA_(2) was related to hemolymph immunity in silkworms. Interestingly, reducing BmsPLA_(2) by RNA interference decreased melanosis (melanistic hemocytes) levels in vivo and in vitro, while BmsPLA_(2) overexpression had the opposite effect. The larval survival and melanization rate in the hemocoel both slowed depending on the PLA_(2) inhibitor dosage. These results demonstrated that BmsPLA_(2) plays a role in melanization during the immune process of silkworms. Surprisingly, the level of BmDDC matched the degree of melanization in various observations. BmDDC expression showed a significant increase, with the peak occurring later than that of BmsPLA_(2) after injection of bacteria, implying that BmsPLA_(2) was activated prior to BmDDC. Moreover, the alteration of BmsPLA_(2) by RNA interference or overexpression led to altered BmDDC levels. These results suggested that BmsPLA_(2) regulates the melanization response in silkworms through BmDDC. Our study proposes a new regulatory mechanism of the melanization response and new directions for understanding the complex immune networks of insects.

Facet-dependent antibacterial activity of Au nanocrystals

Engineered nanomaterials have attracted significantly attention as one of the most promising antimicrobial agents for against multidrug resistant infections.The toxicological responses of nano mate rials are closely related to their physicochemical properties,and establishment of a structure-activity relationship for nanomaterials at the nano-bio interface is of great significance for deep understanding antibacterial toxicity mechanisms of nanomaterials and designing safer antibacterial nanomaterials.In this study,the antibacterial behaviors of well-defined crystallographic facets of a series of Au nanocrystals,including{100}-facet cubes,{110}-facet rhombic dodecahedra,{111}-facet octahedra,{221}-facet trisoctahedra and{720}-facet concave cubes,was investigated,using the model bacteria Staphylococcus aureus.We find that Au nanocrystals display substantial facet-dependent antibacterial activities.The low-index facets of cubes,octahedra,and rhombic dodecahedra show considerable antibacterial activity,whereas the high-index facets of trisoctahedra and concave cubes remained inert under biological conditions.This result is in stark contrast to the previous paradigm that the high-index facets were considered to have higher bioactivity as compared with low-index facets.The antibacterial mechanism studies have shown that the facet-dependent antibacterial behaviors of Au nanocrystals are mainly caused by differential bacterial membrane damage as well as inhibition of cellular enzymatic activity and energy metabolism.The faceted Au nanocrystals are unique in that they do not induce generation of reactive oxygen species,as validated for most antibiotics and antimicrobial nanostructures.Our findings may provide a deeper understanding of facet-dependent toxicological responses and suggest the complexities of the na no material-cell interactions,shedding some light on the development of high performance Au nanomaterials-based antibacterial therapeutics.