226 research outputs found
Genetic Variations in Plasma Circulating DNA of HBV-Related Hepatocellular Carcinoma Patients Predict Recurrence after Liver Transplantation
BACKGROUND: Recurrence prediction of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients undergoing liver transplantation (LT) present a great challenge because of a lack of biomarkers. Genetic variations play an important role in tumor development and metastasis. METHODS: Oligonucleotide microarrays were used to evaluate the genetic characteristics of tumor DNA in 30 HBV-related HCC patients who were underwent LT. Recurrence-related single-nucleotide polymorphism were selected, and their prognostic value was assessed and validated in two independent cohorts of HCC patients (N = 102 and N = 77), using pretransplant plasma circulating DNA. Prognostic significance was assessed by Kaplan-Meier survival estimates and log-rank tests. Multivariate analyses were performed to evaluate prognosis-related factors. RESULTS: rs894151 and rs12438080 were significantly associated with recurrence (P = .003 and P = .004, respectively). Multivariate analyses demonstrated that the co-index of the 2 SNPs was an independent prognostic factor for recurrence (P = .040). Similar results were obtained in the third cohort (N = 77). Furthermore, for HCC patients (all the 3 cohorts) exceeding Milan criteria, the co-index was a prognostic factor for recurrence and survival (P<.001 and P = .002, respectively). CONCLUSIONS: Our study demonstrated first that genetic variations of rs894151 and rs12438080 in pretransplant plasma circulating DNA are promising prognostic markers for tumor recurrence in HCC patients undergoing LT and identify a subgroup of patients who, despite having HCC exceeding Milan criteria, have a low risk of post-transplant recurrence
Recommended from our members
A regulatory mutant on TRIM26 conferring the risk of nasopharyngeal carcinoma by inducing low immune response.
The major histocompatibility complex (MHC) is most closely associated with nasopharyngeal carcinoma (NPC), but the complexity of its genome structure has proven challenging for the discovery of causal MHC loci or genes. We conducted a targeted MHC sequencing in 40 Cantonese NPC patients followed by a two-stage replication in 1065 NPC cases and 2137 controls of Southern Chinese descendent. Quantitative RT-PCR analysis (qRT-PCR) was used to detect gene expression status in 108 NPC and 43 noncancerous nasopharyngeal (NP) samples. Luciferase reporter assay and chromatin immunoprecipitation (ChIP) were used to assess the transcription factor binding site. We discovered that a novel SNP rs117565607_A at TRIM26 displayed the strongest association (OR = 1.909, Pcombined = 2.750 × 10-19 ). We also observed that TRIM26 was significantly downregulated in NPC tissue samples with genotype AA/AT than TT. Immunohistochemistry (IHC) test also found the TRIM26 protein expression in NPC tissue samples with the genotype AA/AT was lower than TT. According to computational prediction, rs117565607 locus was a binding site for the transcription factor Yin Yang 1 (YY1). We observed that the luciferase activity of YY1 which is binding to the A allele of rs117565607 was suppressed. ChIP data showed that YY1 was binding with T not A allele. Significance analysis of microarray suggested that TRIM26 downregulation was related to low immune response in NPC. We have identified a novel gene TRIM26 and a novel SNP rs117565607_A associated with NPC risk by regulating transcriptional process and established a new functional link between TRIM26 downregulation and low immune response in NPC
Systematic biases in determining dust attenuation curves through galaxy SED fitting
While the slope of the dust attenuation curve () is found to
correlate with effective dust attenuation () as obtained through spectral
energy distribution (SED) fitting, it remains unknown how the fitting
degeneracies shape this relation. We examine the degeneracy effects by fitting
SEDs of a sample of local star-forming galaxies (SFGs) selected from the Galaxy
And Mass Assembly survey, in conjunction with mock galaxy SEDs of known
attenuation parameters. A well-designed declining starburst star formation
history is adopted to generate model SED templates with intrinsic UV slope
() spanning over a reasonably wide range. The best-fitting
for our sample SFGs shows a wide coverage, dramatically differing from the
limited range of for a starburst of constant star formation. Our
results show that strong degeneracies between , , and in
the SED fitting induce systematic biases leading to a false --
correlation. Our simulation tests reveal that this relationship can be well
reproduced even when a flat -- relation is taken to build the
input model galaxy SEDs. The variations in best-fitting are dominated
by the fitting errors. We show that assuming a starburst with constant star
formation in SED fitting will result in a steeper attenuation curve, smaller
degeneracy errors, and a stronger -- relation. Our findings
confirm that the -- relation obtained through SED fitting is
likely driven by the systematic biases induced by the fitting degeneracies
between , , and .Comment: 21 pages, 13 figures, accepted for publication in the MNRAS, Comments
welcome
Relationship between bedtime, nighttime sleep duration, and anxiety symptoms in preschoolers in China
BackgroundSleep problems in preschoolers are becoming increasingly prominent, and the association between sleep status and anxiety symptoms has attracted growing attention. However, studies investigating the relationship between bedtime and nighttime sleep duration in preschoolers and their anxiety symptoms remain scant. We used the large sample data from the Longhua Cohort Study of Children in Shenzhen, China (LCCS) to analyze the association between bedtime and sleep in preschoolers and their anxiety symptoms.MethodsA cross-sectional study of 69,138 preschoolers in Longhua District, Shenzhen, China was conducted in 2022. Data on sociodemographic characteristics of families, bedtime, nighttime sleep duration of preschoolers, and their anxiety symptoms (measured by the Spence Preschool Children Anxiety Scale) were collected through a structured questionnaire completed by the parents. Using binary logistic regression models, the relationship between bedtime, nighttime sleep duration, and childhood anxiety symptoms was examined.ResultsThe bedtimes of preschoolers were concentrated between 21:01–22:00 (52.41%). Among the preschoolers, 38.70% had bedtimes later than 22:00, and 75.49% had insufficient nighttime sleep duration. The positive screening rate for anxiety symptoms among preschoolers was 3.50%. After adjusting for confounding factors using binary logistic regression models, compared with preschoolers with bedtime ≤21:00, The OR (95%CI) values of anxiety in preschoolers with bedtime ≥23:01, 22:01–23:00 and 21:01–22:00 were 2.86 (2.21–3.69), 1.51 (1.27–1.79) and 1.48 (1.26–1.76), respectively. Compared with those with sufficient nighttime sleep duration, the OR (95%CI) of children with nighttime sleep duration less than 9 h was 1.36 (1.23–1.51).ConclusionAn association exists between bedtime and nighttime sleep duration in preschoolers and their anxiety symptoms. Preschoolers with 21:00 for bedtime and a nighttime sleep duration of 10 h may have lower anxiety symptoms. These findings support the importance of adequate sleep for preventing anxiety symptoms in children
Search for Quasi-Periodical Oscillations in Precursors of Short and Long Gamma Ray Bursts
The precursors of short and long Gamma Ray Bursts (SGRBs and LGRBs) can serve
as probes of their progenitors, as well as shedding light on the physical
processes of mergers or core-collapse supernovae. Some models predict the
possible existence of Quasi-Periodically Oscillations (QPO) in the precursors
of SGRBs. Although many previous studies have performed QPO search in the main
emission of SGRBs and LGRBs, so far there was no systematic QPO search in their
precursors. In this work, we perform a detailed QPO search in the precursors of
SGRBs and LGRBs detected by Fermi/GBM from 2008 to 2019 using the power density
spectrum (PDS) in frequency domain and Gaussian processes (GP) in time domain.
We do not find any convinced QPO signal with significance above 3 ,
possibly due to the low fluxes of precursors. Finally, the PDS continuum
properties of both the precursors and main emissions are also studied for the
first time, and no significant difference is found in the distributions of the
PDS slope for precursors and main emissions in both SGRBs and LGRBs.Comment: submitte
The Minimum Variation Timescales of X-ray bursts from SGR J1935+2154
The minimum variation timescale (MVT) of soft gamma-ray repeaters can be an
important probe to estimate the emission region in pulsar-like models, as well
as the Lorentz factor and radius of the possible relativistic jet in gamma-ray
burst (GRB)-like models, thus revealing their progenitors and physical
mechanisms. In this work, we systematically study the MVTs of hundreds of X-ray
bursts (XRBs) from SGR J1935+2154 observed by {\it Insight}-HXMT, GECAM and
Fermi/GBM from July 2014 to Jan 2022 through the Bayesian Block algorithm. We
find that the MVTs peak at 2 ms, corresponding to a light travel time
size of about 600 km, which supports the magnetospheric origin in pulsar-like
models. The shock radius and the Lorentz factor of the jet are also constrained
in GRB-like models. Interestingly, the MVT of the XRB associated with FRB
200428 is 70 ms, which is longer than that of most bursts and implies
its special radiation mechanism. Besides, the median of MVTs is 7 ms, shorter
than the median MVTs of 40 ms and 480 ms for short GRBs or long GRBs,
respectively. However, the MVT is independent of duration, similar to GRBs.
Finally, we investigate the energy dependence of MVT and suggest that there is
a marginal evidence for a power-law relationship like GRBs but the rate of
variation is at least about an order of magnitude smaller. These features may
provide an approach to identify bursts with a magnetar origin.Comment: accepted for publication in ApJ
Hypoxia-inducible factor-1 alpha, in association with inflammation, angiogenesis and MYC, is a critical prognostic factor in patients with HCC after surgery
<p>Abstract</p> <p>Background</p> <p>Despite well-studied tumor hypoxia in laboratory, little is known about the association with other pathophysiological events in the clinical view. We investigated the prognostic value of hypoxia-inducible factor-1 alpha (HIF-1alpha) in hepatocellular carcinoma (HCC), and its correlations with inflammation, angiogenesis and MYC oncogene.</p> <p>Methods</p> <p>In a random series of 110 HCC patients, the mRNA of HIF-1alpha, inflammation related factors (COX-2, MMP7 and MMP9), angiogenesis related factors (VEGF and PDGFRA) and MYC in tumor tissue were detected by real-time RT-PCR and HIF-1alpha protein was assessed by immunohistochemistry. The correlations between HIF-1alpha mRNA and the factors mentioned previously, the relationship between HIF-1alpha and clinicopathologic features, and the prognostic value were analyzed.</p> <p>Results</p> <p>The expression of both HIF-1alpha mRNA and protein in HCC were independent prognostic factors for overall survival (OS) (<it>P </it>= 0.012 and <it>P </it>= 0.021, respectively) and disease-free survival (DFS) (<it>P </it>= 0.004 and <it>P </it>= 0.007, respectively) as well. Besides, the high expression of HIF-1alpha mRNA and protein proposed an advanced BCLC stage and more incidence of vascular invasion. The mRNA of HIF-1alpha had significantly positive correlations to that of COX-2, PDGFRA, MMP7, MMP9, MYC, except VEGF. In addition to HIF-1alpha, COX-2 and PDGFRA were also independent prognosticators for OS (<it>P </it>= 0.004 and <it>P </it>= 0.010, respectively) and DFS (<it>P </it>= 0.010 and <it>P </it>= 0.038, respectively).</p> <p>Conclusion</p> <p>HIF-1alpha in HCC plays an important role in predicting patient outcome. It may influence HCC biological behaviors and affect the tumor inflammation, angiogenesis and act in concert with the oncogene MYC. Attaching importance to HIF-1alpha in HCC may improve the prognostic and therapeutic technique.</p
Residual hepatocellular carcinoma after oxaliplatin treatment has increased metastatic potential in a nude mouse model and is attenuated by Songyou Yin
<p>Abstract</p> <p>Background</p> <p>The opposite effects of chemotherapy, which enhance the malignancy of treated cancers such as hepatocellular carcinoma (HCC), are not well understood. We investigated this phenomenon and corresponding mechanisms to develop a novel approach for improving chemotherapy efficacy in HCC.</p> <p>Methods</p> <p>Human hepatocellular carcinoma cell lines HepG2 (with low metastatic potential) and MHCC97L (with moderate metastatic potential) were used for the in vitro study. An orthotopic nude mouse model of human HCC was developed using MHCC97L cells. We then assessed the metastatic potential of surviving tumor cells after in vitro and in vivo oxaliplatin treatment. The molecular changes in surviving tumor cells were evaluated by western blot, immunofluorescence, and immunohistochemistry. The Chinese herbal extract Songyou Yin (composed of five herbs) was investigated in vivo to explore its effect on the metastatic potential of oxaliplatin-treated cancer cells.</p> <p>Results</p> <p>MHCC97L and HepG2 cells surviving oxaliplatin treatment showed enhanced migration and invasion in vitro. Residual HCC after in vivo oxaliplatin treatment demonstrated significantly increased metastasis to the lung (10/12 vs. 3/12) when re-inoculated into the livers of new recipient nude mice. Molecular changes consistent with epithelial-mesenchymal transition (EMT) were observed in oxaliplatin-treated tumor tissues and verified by in vitro experiments. The Chinese herbal extract Songyou Yin (4.2 and 8.4 g/kg) attenuated EMT and inhibited the enhanced metastatic potential of residual HCC in nude mice (6/15 vs. 13/15 and 3/15 vs. 13/15, respectively).</p> <p>Conclusions</p> <p>The surviving HCC after oxaliplatin treatment underwent EMT and demonstrated increased metastatic potential. Attenuation of EMT by Songyou Yin may improve the efficacy of chemotherapy in HCC.</p
Mudskipper genomes provide insights into the terrestrial adaptation of amphibious fishes
Mudskippers are amphibious fishes that have developed morphological and physiological adaptations to match their unique lifestyles. Here we perform whole-genome sequencing of four representative mudskippers to elucidate the molecular mechanisms underlying these adaptations. We discover an expansion of innate immune system genes in the mudskippers that may provide defence against terrestrial pathogens. Several genes of the ammonia excretion pathway in the gills have experienced positive selection, suggesting their important roles in mudskippers’ tolerance to environmental ammonia. Some vision-related genes are differentially lost or mutated, illustrating genomic changes associated with aerial vision. Transcriptomic analyses of mudskippers exposed to air highlight regulatory pathways that are up- or down-regulated in response to hypoxia. The present study provides a valuable resource for understanding the molecular mechanisms underlying water-to-land transition of vertebrates
- …