Circulating Cell-Free DNA

Circulating cell-free DNA (cfDNA) refers to extracellular DNA present in body fluid that may be derived from both normal and diseased cells. The concentration, integrity, genetic, and epigenetic alternations in the cfDNA may suggest pathological conditions of the body, such as inflammation, autoimmune diseases, stress, or even malignancies. cfDNA from patients with malignancies contains variants as those in the tumor tissue cells, thus allowing noninvasive assessment of tumor in real time. The clinical detection of cfDNA is one major application of liquid biopsy and has great application value in the early diagnosis of clinical tumors, real-time progression monitoring, curative effect observation and evaluation, prognosis assessment, and metastasis risk analysis. This chapter summarizes the origin of cell-free DNA and its important clinical applications as a noninvasive biomarker

Toward a density Corr\'{a}di--Hajnal theorem for degenerate hypergraphs

Given an $r$-graph $F$ with $r \ge 2$, let $\mathrm{ex}(n, (t+1) F)$ denote the maximum number of edges in an $n$-vertex $r$-graph with at most $t$ pairwise vertex-disjoint copies of $F$. Extending several old results and complementing prior work [J. Hou, H. Li, X. Liu, L.-T. Yuan, and Y. Zhang. A step towards a general density Corr\'{a}di--Hajnal theorem. arXiv:2302.09849, 2023.] on nondegenerate hypergraphs, we initiate a systematic study on $\mathrm{ex}(n, (t+1) F)$ for degenerate hypergraphs $F$. For a broad class of degenerate hypergraphs $F$, we present near-optimal upper bounds for $\mathrm{ex}(n, (t+1) F)$ when $n$ is sufficiently large and $t$ lies in intervals $\left[0, \frac{\varepsilon \cdot \mathrm{ex}(n,F)}{n^{r-1}}\right]$, $\left[\frac{\mathrm{ex}(n,F)}{\varepsilon n^{r-1}}, \varepsilon n \right]$, and $\left[ (1-\varepsilon)\frac{n}{v(F)}, \frac{n}{v(F)} \right]$, where $\varepsilon > 0$ is a constant depending only on $F$. Our results reveal very different structures for extremal constructions across the three intervals, and we provide characterizations of extremal constructions within the first interval. Additionally, for graphs, we offer a characterization of extremal constructions within the second interval. Our proof for the first interval also applies to a special class of nondegenerate hypergraphs, including those with undetermined Tur\'{a}n densities, partially improving a result in [J. Hou, H. Li, X. Liu, L.-T. Yuan, and Y. Zhang. A step towards a general density Corr\'{a}di--Hajnal theorem. arXiv:2302.09849, 2023.]Comment: 37 pages, 4 figures, comments are welcom

Electrodeposition of pyrrole and 3-(4-tert-butylphenyl)thiophene copolymer for supercapacitor applications

The electropolymerization of pyrrole (Py), 3-(4-tert-butylphenyl)thiophene (TPT) monomer or the mixed Py and TPT monomers on stainless steel mesh substrate were performed in 1 M LiClO4/acetonitrile solution. A much lower potential of 0.75 V was required for the co-electropolymerization of Py and TPT, in sharp contrast to that of 1.20 V for poly(3-(4-tert-butylphenyl)thiophene) (PTPT) formation. The resultant homopolymers and copolymer were characterized with FESEM and FTIR, and assembled into supercapacitors to investigate their electrochemical performances. The copolymer electrode delivered the highest specific capacitance of 291 F g−1 at a scan rate of 5 mV s−1, in comparison with that of 216 and 26 F g−1 for PPy and PTPT, respectively. This copolymer also exhibited a greatly improved cycling stability – only 9% of capacitance decrease was observed after 1000 charging–discharging cycles at a current density of 5 A g−1, while the capacitance losses for PPy and PTPT were 16% and 60%, respectively

Early-onset pancreatic neuroendocrine neoplasms: A distinct disease with improved survival compared with old individuals

BackgroundThe incidence, clinicopathologic characteristics, treatment patterns, and survival of early-onset pancreatic neuroendocrine neoplasms (EOPanNENs) have not been well explored.MethodsPatients diagnosed with PanNENs were identified from the SEER database between 2000 and 2018. EOPanNENs were defined as diagnosis in patients aged less than 50 years, while the remaining were defined as later-onset pancreatic neuroendocrine neoplasms (LOPanNENs). Incidence, clinical features, management, and prognosis were analyzed in our study. Multivariable analyses were performed to identify factors associated with overall survival (OS) in EOPanNENs and LOPanNENs, respectively.ResultsA total of 5172 patients with PanNENs were included: 1267 (24.5%) in the EOPanNENs cohort and 3905 (75.5%) in the LOPanNENs cohort. The age-adjusted incidence rate significantly increased among later-onset cases, while it remained relatively stable in early-onset cases. EOPanNENs were more frequently to be female, unmarried, and with better tumor differentiation compared with LOPanNENs. Of note, early-onset patients presented with a higher rate of lymph node involvement, and they were more likely to receive surgical treatment. For local-regional disease at presentation, surgery alone was the most frequently used regimen over the last two decades. With regard to distant stage, a combination of surgery and chemotherapy was more often utilized. Risk factors for PanNENs survival were more correlated with LOPanNENs compared with EOPanNENs. The OS and cancer-specific survival (CSS) were significantly better in the EOPanNENs group. Further analyses showed that EOPanNENs ≤ 2cm were associated with more favorable survival outcomes than EOPanNENs>2cm.ConclusionEOPanNENs are a clinically rare and distinct entity from LOPanNENs. The advantages in survival for the EOPanNENs cohort over time were largely driven by the indolent clinical courses including better tumor differentiation and intensified surgical treatment. Further investigations are warranted to better understand the characteristics of this disease subgroup

Characterisation of Thinopyrum bessarabicum chromosomes through genome-wide introgressions into wheat

Thinopyrum bessarabicum (2n = 2x = 14, JJ) is an important source for new genetic variation for wheat improvement due to its salinity tolerance and disease resistance. Its practical utilisation in wheat improvement can be facilitated through development of genome-wide introgressions leading to a variety of different wheat–Th. bessarabicum translocation lines. In this study, we report the generation of 12 such wheat–Th. bessarabicum recombinant lines, through two different crossing strategies, which were characterized using sequential chromosome single colour and multi-colour genomic in situ hybridization (sc-GISH and mc-GISH), multi-colour fluorescent in situ hybridization (mc-FISH) and single nucleotide polymorphic (SNP) DNA markers. We also detected 13 lines containing different Th. bessarabicum chromosome aberrations through sc-GISH. Through a combination of molecular and cytological analysis of all the 25 lines containing Th. bessarabicum recombinants and chromosome aberrations we were able to physically map 1150 SNP markers onto seven Th. bessarabicum J chromosomes which were divided into 36 segmental blocks. Comparative analysis of the physical map of Th. bessarabicum and the wheat genome showed that synteny between the two species is highly conserved at the macro-level and confirmed that Th. bessarabicum contains the 4/5 translocation also present in the A genome of wheat. These wheat–Th. bessarabicum recombinant lines and SNP markers provide a useful genetic resource for wheat improvement with the latter having a wider impact as a tool for detection of introgressions from other Thinopyrum species containing the J or a closely-related genome such as Thinopyrum intermedium (JrJrJvsJvsStSt) and Thinopyrum elongatum (EeEe), respectively

Mycoplasma hyorhinis infection in gastric carcinoma and its effects on the malignant phenotypes of gastric cancer cells

<p>Abstract</p> <p>Background</p> <p><it>Mycoplasma hyorhinis </it>infection has been postulated to play a role in the development of several types of cancer, but the direct evidence and mechanism remained to be determined.</p> <p>Methods</p> <p>Immunohistochemistry assay and nested polymerase-chain reaction (PCR) were performed to examine the <it>mycoplasma hyorhinis </it>infection in gastric cancer tissues. Statistical analysis was used to check the association between mycoplasma infection and clinicopathologic parameters. Transwell chamber assay and metastasis assay were used to evaluate <it>mycoplasma hyorhinis</it>' effects on metastasis in vitro and in vivo. <it>Mycoplasma hyorhinis</it>-induced extracellular signal-regulated kinase (ERK) and epidermal growth factor receptor (EGFR) activation were investigated by Western blot.</p> <p>Results</p> <p>My<it>coplasma hyorhinis </it>infection in gastric cancer tissues was revealed and statistical analysis indicated a significant association between mycoplasma infections and lymph node metastasis, Lauren's Classification, TNM stage, and age of the patients. <it>Mycoplasma hyorhinis </it>promoted tumor cell migration, invasion and metastasis <it>in vitro </it>and <it>in vivo</it>, which was possibly associated with the enhanced phosphorylation of EGFR and ERK1/2. The antibody against p37 protein of <it>Mycoplasma hyorhinis </it>could inhibit the migration of the infected cells.</p> <p>Conclusions</p> <p>The infection of <it>m</it>y<it>coplasma hyorhinis </it>may contribute to the development of gastric cancer and <it>Mycoplasma hyorhinis</it>-induced malignant phenotypes were possibly mediated by p37.</p

DESIGN AND EXPERIMENT OF A COMBINED TYPE SPATIALLY LAYERED PROPORTIONAL FERTILIZATION DEVICE

ABSTRACT To solve the problems of low efficiency, poor fertilizer application, and low fertilizer utilization rate of existing wheat layered fertilization devices (LFD). This paper proposed a layered fertilization mode combining shallow fertilizer application based on rotary tillage and middle/deep fertilizer application of layered fertilizer shovel (LFS), and designed a combined spatial layered fertilization device with a fixed proportion. A discrete element simulation model consisting of soil, LFS and fertilizer was established. Taking the variation coefficients of fertilization amount as the evaluation indicator and changing the sidewall deflection angle, rear inclination angle, upper channel length of LFS, a three-factor three-level quadratic rotational orthogonal experiment was carried out. The optimal parameter combination was obtained: the deflection angle was 9.5°, the inclination angle was 57°, and the channel length was 280 mm. The corresponding variation coefficients of fertilizer application depth were 4.55%, 8.44%, and 6.93% while working stably under the optimal combination, which is consistent with the simulation results. The results showed that LFD can apply fertilizer underground in three layers: 0~10, 15, and 20 cm, with the proportion of shallow, middle, and deep fertilizers being 30%, 35%, and 35%, which can meet the agronomic requirements for winter wheat growth

Transcription factor MYB26 is key to spatial specificity in anther secondary thickening formation

Successful fertilization relies on the production and effective release of viable pollen. Failure of anther opening (dehiscence), results in male sterility, although the pollen may be fully functional. MYB26 regulates the formation of secondary thickening in the anther endothecium, which is critical for anther dehiscence and fertility. Here, we show that although the MYB26 transcript shows expression in multiple floral organs, the MYB26 protein is localized specifically to the anther endothecium nuclei and that it directly regulates two NAC domain genes, NST1 and NST2, which are critical for the induction of secondary thickening biosynthesis genes. However, there is a complex relationship of regulation between these genes and MYB26. Using DEX-inducible MYB26 lines and overexpression in the various mutant backgrounds, we have shown that MYB26 up-regulates both NST1 and NST2 expression. Surprisingly normal thickening and fertility rescue does not occur in the absence of MYB26, even with constitutively induced NST1 and NST2, suggesting an additional essential role for MYB26 in this regulation. Combined overexpression of NST1 and NST2 in myb26 facilitates limited ectopic thickening in the anther epidermis, but not in the endothecium, and thus fails to rescue dehiscence. Therefore, by a series of regulatory controls through MYB26, NST1, NST2, secondary thickening is formed specifically within the endothecium; this specificity is essential for anther opening

Accelerating Magnetic Resonance Parametric Mapping Using Simultaneously Spatial Patch-based and Parametric Group-based Low-rank Tensors (SMART)

Quantitative magnetic resonance (MR) parametric mapping is a promising approach for characterizing intrinsic tissue-dependent information. However, long scan time significantly hinders its widespread applications. Recently, low-rank tensor has been employed and demonstrated good performance in accelerating MR parametricmapping. In this study, we propose a novel method that uses spatial patch-based and parametric group-based low rank tensors simultaneously (SMART) to reconstruct images from highly undersampled k-space data. The spatial patch-based low-rank tensor exploits the high local and nonlocal redundancies and similarities between the contrast images in parametric mapping. The parametric group based low-rank tensor, which integrates similar exponential behavior of the image signals, is jointly used to enforce the multidimensional low-rankness in the reconstruction process. In vivo brain datasets were used to demonstrate the validity of the proposed method. Experimental results have demonstrated that the proposed method achieves 11.7-fold and 13.21-fold accelerations in two-dimensional and three-dimensional acquisitions, respectively, with more accurate reconstructed images and maps than several state-of-the-art methods. Prospective reconstruction results further demonstrate the capability of the SMART method in accelerating MR quantitative imaging.Comment: 15 pages, 12 figure