140 research outputs found
The Stability of Medicinal Plant microRNAs in the Herb Preparation Process
Herbal medicine is now globally accepted as a valid alternative system of
pharmaceutical therapies. Various studies around the world have been initiated
to develop scientific evidence-based herbal therapies. Recently, the
therapeutic potential of medicinal plant derived miRNAs has attracted great
attraction. MicroRNAs have been indicated as new bioactive ingredients in
medicinal plants. However, the stability of miRNAs during the herbal
preparation process and their bioavailability in humans remain unclear. Viscum
album L. (European mistletoe) has been widely used in folk medicine for the
treatment of cancer and cardiovascular diseases. Our previous study has
indicated the therapeutic potential of mistletoe miRNAs by using
bioinformatics tools. To evaluate the stability of these miRNAs, various
mistletoe extracts that mimic the clinical medicinal use as well as
traditional folk medicinal use were prepared. The mistletoe miRNAs including
miR166a-3p, miR159a, miR831-5p, val-miR218 and val-miR11 were quantified by
stem-loop qRT-PCR. As a result, miRNAs were detectable in the majority of the
extracts, indicating that consumption of medicinal plant preparations might
introduce miRNAs into mammals. The factors that might cause miRNA degradation
include ultrasonic treatment, extreme heat, especially RNase treatment, while
to be associated with plant molecules (e.g., proteins, exosomes) might be an
efficient way to protect miRNAs against degradation. Our study confirmed the
stability of plant derived miRNAs during herb preparations, suggesting the
possibility of functionally intact medicinal plant miRNAs in mammals
Identification of Viscum album L. miRNAs and prediction of their medicinal values
MicroRNAs (miRNAs) are a class of approximately 22 nucleotides single-stranded
non-coding RNA molecules that play crucial roles in gene expression. It has
been reported that the plant miRNAs might enter mammalian bloodstream and have
a functional role in human metabolism, indicating that miRNAs might be one of
the hidden bioactive ingredients in medicinal plants. Viscum album L.
(Loranthaceae, European mistletoe) has been widely used for the treatment of
cancer and cardiovascular diseases, but its functional compounds have not been
well characterized. We considered that miRNAs might be involved in the
pharmacological activities of V. album. High-throughput Illumina sequencing
was performed to identify the novel and conserved miRNAs of V. album. The
putative human targets were predicted. In total, 699 conserved miRNAs and 1373
novel miRNAs have been identified from V. album. Based on the combined use of
TargetScan, miRanda, PITA, and RNAhybrid methods, the intersection of 30697
potential human genes have been predicted as putative targets of 29 novel
miRNAs, while 14559 putative targets were highly enriched in 33 KEGG pathways.
Interestingly, these highly enriched KEGG pathways were associated with some
human diseases, especially cancer, cardiovascular diseases and neurological
disorders, which might explain the clinical use as well as folk medicine use
of mistletoe. However, further experimental validation is necessary to confirm
these human targets of mistletoe miRNAs. Additionally, target genes involved
in bioactive components synthesis in V. album were predicted as well. A total
of 68 miRNAs were predicted to be involved in terpenoid biosynthesis, while
two miRNAs including val-miR152 and miR9738 were predicted to target
viscotoxins and lectins, respectively, which increased the knowledge regarding
miRNA-based regulation of terpenoid biosynthesis, lectin and viscotoxin
expressions in V. album
Surface Roughness Gradients Reveal TopographyâSpecific Mechanosensitive Responses in Human Mesenchymal Stem Cells
The topographic features of an implant, which mechanically regulate cell behaviors and functions, are critical for the clinical success in tissue regeneration. How cells sense and respond to the topographical cues, e.g., interfacial roughness, is yet to be fully understood and even debatable. Here, the mechanotransduction and fate determination of human mesenchymal stem cells (MSCs) on surface roughness gradients are systematically studied. The broad range of topographical scales and highâthroughput imaging is achieved based on a catecholic polyglycerol coating fabricated by a oneâstepâtilted dipâcoating approach. It is revealed that the adhesion of MSCs is biphasically regulated by interfacial roughness. The cell mechanotransduction is investigated from focal adhesion to transcriptional activity, which explains that cellular response to interfacial roughness undergoes a direct forceâdependent mechanism. Moreover, the optimized roughness for promoting cell fate specification is explored
Pharmacokinetics of mequindox after intravenous and intramuscular administration to goat
Pharmacokinetics and bioavailability of mequindox were determined after single intravenous (i.v.) or intramuscular (i.m.) administrations of 7 mg/kg body weight (b.w.) to 10 healthy adult goats. Plasma mequindox concentrations were measured by high performance liquid chromatography. Pharmacokinetics were best described by a two-compartment open model and an one-compartment open model for i.v. and i.m. groups, respectively. The elimination half-life and volume of distribution after i.v. and i.m. administrations were statistically different (t1/2β, 1.8 to 1.5 h, P < 0.05 and Vd, 0.35 to 0.45 L¡kg-1, P < 0.05, respectively). Mequindox was rapidly (t1/2a, 0.28 h) and almost completely absorbed (F, 99.8%) after i.m. administration. In conclusion, 2~3 times daily i.v. and i.m. administration of mequindox (7 mg/kg b.w.) in goats may be useful in treatment of infectious diseases caused by sensitive pathogens. The plasma disposition kinetics of mequindox in goats is reported for the first time.Key words: Mequindox, pharmacokinetics, high performance liquid chromatography (HPLC), goats
A Rapid, Non-invasive Method for Anatomical Observations of Tadpole Vertebrae in Vivo
The tadpole is a critical stage in the amphibian life cycle and plays an important role during the transition from the aquatic to the terrestrial stage. However, there is a large gap in tadpole research, which represents a vital component of our understanding of the diversity and complexity of the life history traits of amphibians, especially their developmental biology. Some aspects of this gap are due to limited research approaches. To date, X-ray microcomputed tomography (micro-CT) has been widely used to conduct osteology research in adult amphibians and reptiles, but little is known about whether this tool can be applied in tadpole studies. Thus, we compared the results of two methods (the bone-cartilage double-staining technique and micro-CT) to study vertebrae in tadpole specimens. The results revealed no significant difference between the two methods in determining the number of vertebrae, and micro-CT represents a rapid, non-invasive, reliable method of studying tadpole vertebrae. When scanning tadpoles, voltage is the most critical of the scanning parameters (voltage, current and scan time), and moderate scanning parameters are recommended. In addition, micro-CT performed better using specimens stored in 70% ethanol than those preserved in 10% formalin. Finally, we suggest that micro-CT should be more widely applied in herpetological research to increase specimen utilization
Peripheral inflammation and neurocognitive impairment: correlations, underlying mechanisms, and therapeutic implications
Cognitive impairments, such as learning and memory deficits, may occur in susceptible populations including the elderly and patients who are chronically ill or have experienced stressful events, including surgery, infection, and trauma. Accumulating lines of evidence suggested that peripheral inflammation featured by the recruitment of peripheral immune cells and the release of pro-inflammatory cytokines may be activated during aging and these conditions, participating in peripheral immune system-brain communication. Lots of progress has been achieved in deciphering the core bridging mechanism connecting peripheral inflammation and cognitive impairments, which may be helpful in developing early diagnosis, prognosis evaluation, and prevention methods based on peripheral blood circulation system sampling and intervention. In this review, we summarized the evolving evidence on the prevalence of peripheral inflammation-associated neurocognitive impairments and discussed the research advances in the underlying mechanisms. We also highlighted the prevention and treatment strategies against peripheral inflammation-associated cognitive dysfunction
Incremental Model Predictive Control Exploiting Time-Delay Estimation for a Robot Manipulator
This article proposes a new incremental model predictive control (IMPC) strategy, which allows for constrained control of a robot manipulator, while the resulting incremental model is derived without a concrete mathematical system model. First, to reduce dependence on the nominal model of robot manipulators, the continuous-time nonlinear system model is approximated by an incremental system using the time-delay estimation (TDE). Then, based on the incremental system, the tracking IMPC is designed in the framework of MPC without terminal ingredients. Thus, compared with existing MPC methods, the nominal mathematical model is not required. Moreover, we investigate reachable reference trajectories and confirm the local input-to-state stability (ISS) of IMPC, considering the bounded TDE error as the disturbance of the incremental system. For reachable reference trajectories, the local ISS of IMPC is analyzed using the continuity of the value function, and the cumulative error bound is not overconservative. Finally, several real-time experiments are conducted to verify the effectiveness of IMPC. Experimental results show that the system can achieve optimal control performance while guaranteeing that input and state constraints are not violated
Integrative bioinformatics approaches to establish potential prognostic immune-related genes signature and drugs in the non-small cell lung cancer microenvironment
Introduction: Research has revealed that the tumor microenvironment (TME) is associated with the progression of malignancy. The combination of meaningful prognostic biomarkers related to the TME is expected to be a reliable direction for improving the diagnosis and treatment of non-small cell lung cancer (NSCLC).Method and Result: Therefore, to better understand the connection between the TME and survival outcomes of NSCLC, we used the âDESeq2â R package to mine the differentially expressed genes (DEGs) of two groups of NSCLC samples according to the optimal cutoff value of the immune score through the ESTIMATE algorithm. A total of 978 up-DEGs and 828 down-DEGs were eventually identified. A fifteen-gene prognostic signature was established via LASSO and Cox regression analysis and further divided the patients into two risk sets. The survival outcome of high-risk patients was significantly worse than that of low-risk patients in both the TCGA and two external validation sets (p-value < 0.05). The gene signature showed high predictive accuracy in TCGA (1-year area under the time-dependent ROC curve (AUC) = 0.722, 2-year AUC = 0.708, 3-year AUC = 0.686). The nomogram comprised of the risk score and related clinicopathological information was constructed, and calibration plots and ROC curves were applied, KEGG and GSEA analyses showed that the epithelial-mesenchymal transition (EMT) pathway, E2F target pathway and immune-associated pathway were mainly involved in the high-risk group. Further somatic mutation and immune analyses were conducted to compare the differences between the two groups. Drug sensitivity provides a potential treatment basis for clinical treatment. Finally, EREG and ADH1C were selected as the key prognostic genes of the two overlapping results from PPI and multiple Cox analyses. They were verified by comparing the mRNA expression in cell lines and protein expression in the HPA database, and clinical validation further confirmed the effectiveness of key genes.Conclusion: In conclusion, we obtained an immune-related fifteen-gene prognostic signature and potential mechanism and sensitive drugs underling the prognosis model, which may provide accurate prognosis prediction and available strategies for NSCLC
Characterization of a novel N-acetylneuraminic acid lyase favoring industrial N-acetylneuraminic acid synthesis process
N-Acetylneuraminic acid lyase (NAL, E.C. number 4.1.3.3) is a Class I aldolase that catalyzes the reversible aldol cleavage of N-acetylneuraminic acid (Neu5Ac) from pyruvate and N-acetyl-D-mannosamine (ManNAc). Due to the equilibrium favoring Neu5Ac cleavage, the enzyme catalyzes the rate-limiting step of two biocatalytic reactions producing Neu5Ac in industry. We report the biochemical characterization of a novel NAL from a âGRASâ (General recognized as safe) strain C. glutamicum ATCC 13032 (CgNal). Compared to all previously reported NALs, CgNal exhibited the lowest kcat/Km value for Neu5Ac and highest kcat/Km values for ManNAc and pyruvate, which makes CgNal favor Neu5Ac synthesis the most. The recombinant CgNal reached the highest expression level (480 mg/L culture), and the highest reported yield of Neu5Ac was achieved (194 g/L, 0.63 M). All these unique properties make CgNal a promising biocatalyst for industrial Neu5Ac biosynthesis. Additionally, although showing the best Neu5Ac synthesis activity among the NAL family, CgNal is more related to dihydrodipicolinate synthase (DHDPS) by phylogenetic analysis. The activities of CgNal towards both NAL's and DHDPS' substrates are fairly high, which indicates CgNal a bi-functional enzyme. The sequence analysis suggests that CgNal might have adopted a unique set of residues for substrates recognition
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