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This paper considers a class of Caputo fractional-order genetic regulatory networks with time-varying lags in biomedicine and life sciences. Applying some features of Mittag-Leffler function and contraction mapping principle, the sufficient conditions are gained to ensure the existence and uniqueness of S-asymptotically co-periodic solution of the model. Based on comparison principle and stability theorem of linear delayed Caputo fractional-order differential equations, global asymptotical stability of the model is also investigated. The work of this article can improve and expand some existing results. [ABSTRACT FROM AUTHOR]

Limitation of excessive inflammation due to selective degradation of pro-inflammatory proteins is one of the cytoprotective functions attributed to autophagy. In the current study, we highlight that selective autophagy also plays a vital role in promoting the establishment of a robust inflammatory response. Under inflammatory conditions, here TLR3-activation by poly(I:C) treatment, the inflammation repressor TNIP1 (TNFAIP3 interacting protein 1) is phosphorylated by Tank-binding kinase 1 (TBK1) activating an LIR motif that leads to the selective autophagy-dependent degradation of TNIP1, supporting the expression of pro-inflammatory genes and proteins. This selective autophagy efficiently reduces TNIP1 protein levels early (0-4 h) upon poly(I:C) treatment to allow efficient initiation of the inflammatory response. At 6 h, TNIP1 levels are restored due to increased transcription avoiding sustained inflammation. Thus, similarly as in cancer, autophagy may play a dual role in controlling inflammation depending on the exact state and timing of the inflammatory response. [ABSTRACT FROM AUTHOR]

Using time-scale calculus and construction of a suitable Lyapunov functional, the permanence and uniform asymptotical stability of a ratio-dependent Leslie model with feedback control on time scales are studied. The results of this paper extend some recent research results. An illustrative example with numerical simulations is employed to visually manifest the theoretical findings. [ABSTRACT FROM AUTHOR]

Mitophagy is an important quality-control mechanism in eukaryotic cells, and defects in mitophagy correlate with aging phenomena and neurodegenerative disorders. It is known that different mitochondrial matrix proteins undergo mitophagy with very different rates but, to date, the mechanism underlying this selectivity at the individual protein level has remained obscure. We now present evidence indicating that protein phosphorylation within the mitochondrial matrix plays a mechanistic role in regulating selective mitophagic degradation in yeast via involvement of the Aup1 mitochondrial protein phosphatase, as well as 2 known matrix-localized protein kinases, Pkp1 and Pkp2. By focusing on a specific matrix phosphoprotein reporter, we also demonstrate that phospho-mimetic and nonphosphorylatable point mutations at known phosphosites in the reporter increased or decreased its tendency to undergo mitophagy. Finally, we show that phosphorylation of the reporter protein is dynamically regulated during mitophagy in an Aup1-dependent manner. Our results indicate that structural determinants on a mitochondrial matrix protein can govern its mitophagic fate, and that protein phosphorylation regulates these determinants. [ABSTRACT FROM AUTHOR]

In this article concerns the semiclassical Choquard equation -ε² ∆u+ V (x)u = ε² ( 1 |·| ∗ u 2) u for x ∈ R³ and small ε. We establish the existence of a sequence of localized nodal solutions concentrating near a given local minimum point of the potential function V, by means of the perturbation method and the method of invariant sets of descending flow. [ABSTRACT FROM AUTHOR]

In this paper, we present a new approach via variational methods and critical point theory to obtain the existence and multiplicity of solutions to a class of damped vibration problems with impulsive effects on time scales. By establishing a proper variational set, two existence results and two multiplicity results are obtained. Finally, one example is presented to illustrate the feasibility and effectiveness of our results. [ABSTRACT FROM AUTHOR]

Background Wheat (Triticum aestivum L.) is an economically important grain crop. Two-dimensional gelbased approaches are limited by the low identification rate of proteins and lack of accurate protein quantitation. The recently developed isobaric tag for relative and absolute quantitation (iTRAQ) method allows sensitive and accurate protein quantification. Here, we performed the first iTRAQ-based quantitative proteome and phosphorylated proteins analyses during wheat grain development. Results The proteome profiles and phosphoprotein characterization of the metabolic proteins during grain development of the elite Chinese bread wheat cultivar Yanyou 361 were studied using the iTRAQ-based quantitative proteome approach, TiO2 microcolumns, and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Among 1,146 non-redundant proteins identified, 421 showed at least 2-fold differences in abundance, and they were identified as differentially expressed proteins (DEPs), including 256 upregulated and 165 downregulated proteins. Of the 421 DEPs, six protein expression patterns were identified, most of which were up, down, and up-down expression patterns. The 421 DEPs were classified into nine functional categories mainly involved in different metabolic processes and located in the membrane and cytoplasm. Hierarchical clustering analysis indicated that the DEPs involved in starch biosynthesis, storage proteins, and defense/stress-related proteins significantly accumulated at the late grain development stages, while those related to protein synthesis/assembly/degradation and photosynthesis showed an opposite expression model during grain development. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis of 12 representative genes encoding different metabolic proteins showed certain transcriptional and translational expression differences during grain development. Phosphorylated proteins analyses demonstrated that 23 DEPs such as AGPase, sucrose synthase, Hsp90, and serpins were phosphorylated in the developing grains and were mainly involved in starch biosynthesis and stress/defense. Conclusions Our results revealed a complex quantitative proteome and phosphorylation profile during wheat grain development. Numerous DEPs are involved in grain starch and protein syntheses as well as adverse defense, which set an important basis for wheat yield and quality. Particularly, some key DEPs involved in starch biosynthesis and stress/defense were phosphorylated, suggesting their roles in wheat grain development. [ABSTRACT FROM AUTHOR]

In this article concerns the semiclassical Choquard equation −ε²∆u+ V (x)u = ε−2 ( 1/|·| ∗ u²)u for x ∈ R³ and small ε. We establish the existence of a sequence of localized nodal solutions concentrating near a given local minimum point of the potential function V, by means of the perturbation method and the method of invariant sets of descending flow. [ABSTRACT FROM AUTHOR]

This article concerns the coupled Schrödinger system in whole space RN { -ε²Δu + V(x)u = P (x)|u|p-2u + Q(x)|u|p/2-2u|v|p/2, -ε²Δu + V(x)u = Q(x)|u|p/2|v| + P(x)|v|p-2v, where ε > 0 is a small parameter. Under some suitable conditions, we obtain the existence of ground state for ε > 0 via the Nehari manifold and concentration-compactness principles. Furthermore, we prove these ground state solutions concentrate at some set related to V, P and Q. [ABSTRACT FROM AUTHOR]

Esophageal cancer is one of the most common type of malignancies. Telomerase activity, which is absent or weakly detected in the majority of human somatic cells, is elevated in esophageal cancer. Although azidothymidine (AZT), a reverse transcriptase inhibitor, has been utilized as a treatment for tumors, its role in treating esophageal cancer has not been confirmed. The aim of the present study was to determine the effect of AZT on telomerase activity and the proliferation of the human esophageal cancer cell line TE‑11. A telomeric repeat amplification assay was utilized to detect telomerase activity following treatment of TE‑11 cells with AZT. The effect of AZT on TE‑11 cell cycle distribution was determined by flow cytometry. Cellular DNA damage was evaluated by a comet assay and an MTT assay demonstrated that AZT significantly inhibited the viability of TE‑11 cells, in a time‑and dose‑dependent manner. In addition, TE‑11 cells treated with various concentrations of AZT exhibited a significant reduction in telomerase activity and percentage of cells in the G1/G0 phase, and an increase in the percentage of cells in the S phase. High doses of AZT caused DNA damage, and enhanced the expression levels of γ‑H2A histone family member X and phosphorylated checkpoint kinase 2 in TE‑11 cells. These results demonstrated that AZT effectively inhibits proliferation of the TE‑11 human esophageal cancer cell line in vitro. The growth inhibitory effects were associated with a reduction in telomerase activity, S and G2/M phase cell cycle arrest, and enhanced DNA damage, suggesting that AZT may be utilized in the clinic for the treatment of esophageal cancer. [ABSTRACT FROM AUTHOR]

Background Thorough understanding of seed starch biosynthesis and accumulation mechanisms is of great importance for agriculture and crop improvement strategies. We conducted the first comprehensive study of the dynamic development of starch granules and the regulation of starch biosynthesis in Brachypodium distachyon and compared the findings with those reported for common wheat (Chinese Spring, CS) and Aegilops peregrina. Results Only B-granules were identified in Brachypodium Bd21, and the shape variation and development of starch granules were similar in the B-granules of CS and Bd21. Phylogenetic analysis showed that most of the Bd21 starch synthesis-related genes were more similar to those in wheat than in rice. Early expression of key genes in Bd21 starch biosynthesis mediate starch synthesis in the pericarp; intermediate-stage expression increases the number and size of starch granules. In contrast, these enzymes in CS and Ae. peregrina were mostly expressed at intermediate stages, driving production of new B-granules and increasing the granule size, respectively. Immunogold labeling showed that granule-bound starch synthase (GBSSI; related to amylose synthesis) was mainly present in starch granules: at lower levels in the B-granules of Bd21 than in CS. Furthermore, GBSSI was phosphorylated at threonine 183 and tyrosine 185 in the starch synthase catalytic domain in CS and Ae. peregrina, but neither site was phosphorylated in Bd21, suggesting GBSSI phosphorylation could improve amylose biosynthesis. Conclusions Bd21 contains only B-granules, and the expression of key genes in the three studied genera is consistent with the dynamic development of starch granules. GBSSI is present in greater amounts in the B-granules of CS than in Bd21; two phosphorylation sites (Thr183 and Tyr185) were found in Triticum and Aegilops; these sites were not phosphorylated in Bd21. GBSSI phosphorylation may reflect its importance in amylose synthesis. [ABSTRACT FROM AUTHOR]

Let T be a periodic time scale. We use Krasnoselskii's fixed point theorem to show that the neutral functional differential equation with impulses x (t) = -A(t)xσ(t) + gΔ(t, x(t - h(t))) + f(t, x(t), x(t - h(t))), t ≠ tj, t ∈ T, x(tj+) = x(tj-) + Ij(x(tj)), j ∈ Z+ has a periodic solution. Under a slightly more stringent conditions we show that the periodic solution is unique using the contraction mapping principle. [ABSTRACT FROM AUTHOR]

Musk deer (Moschidae), whose secretion is an expensive and irreplaceable component of traditional medicine, have become endangered in the wild due to habitat fragmentation and over-exploitation. In recent years, China has had success in the artificial breeding of forest musk deer, thus relieving the pressure on wild populations. However, many farmed populations are experiencing degradation, and little genetic information is available for conservation management. In this study, we selected 274 individuals from three typical captive populations (originated from the Ta-pa Mountains (Tp), the midrange of the Qinling Mountains (Ql) and the Western Sichuan Plateau (WS), respectively) to evaluate the genetic variations. A total of more than 3.15 billion high-quality clean reads and 4.37 million high-quality SNPs were generated by RAD sequencing. Based on the analysis, we found that captive forest musk deer populations exhibit a relatively low level of genetic diversity. Ql displayed a higher level of genetic diversity than the Tp and WS populations. Tp and WS had experienced population bottlenecks in the past as inferred from the values of Tajima’s D. There were high levels of heterozygote deficiency caused by inbreeding within the three populations. Population structure analysis suggested that the three populations have evolved independently, and a moderate amount of genetic differentiation has developed, although there was a low level of gene flow between the Ql and Tp populations. Furthermore, the average quantities of musk secreted by musk deer in the Tp and WS populations were significantly higher than that in the Ql population. The present genetic information should be considered in management plans for the conservation and utilization of musk deer from captive breeding. [ABSTRACT FROM AUTHOR]