The steady-state fully resonant wave system, consisting of two progressive primary waves in finite water depth and all components due to nonlinear interaction, is investigated in detail by means of ...analytically solving the fully nonlinear wave equations as a nonlinear boundary-value problem. It is found that multiple steady-state fully resonant waves exist in some cases which have no exchange of wave energy at all, so that the energy spectrum is time-independent. Further, the steady-state resonant wave component may contain only a small proportion of the wave energy. However, even in these cases, there usually exist time-dependent periodic exchanges of wave energy around the time-independent energy spectrum corresponding to such a steady-state fully resonant wave, since it is hard to be exactly in such a balanced state in practice. This view serves to deepen and enrich our understanding of the resonance of gravity waves.
Abrupt depth transitions (ADTs) have recently been identified as potential causes of ‘rogue’ ocean waves. When stationary and (close-to-) normally distributed waves travel into shallower water over ...an ADT, distinct spatially localized peaks in the probability of extreme waves occur. These peaks have been predicted numerically, observed experimentally, but not explained theoretically. Providing this theoretical explanation using a leading-order-physics-based statistical model, we show, by comparing to new experiments and numerical simulations, that the peaks arise from the interaction between linear free and second-order bound waves, also present in the absence of the ADT, and new second-order free waves generated due to the ADT.
Ginsenoside Rb1 (GRb1), one of the principle active components of Panax ginseng, has been reported to reduce inflammation in various diseases. In the present study, we investigated whether GRb1 has ...an anti-inflammatory effect on postoperative ileus (POI) and further contributes to the recovery of gastrointestinal motility. POI was induced in rats by intestinal manipulation. The POI rats received 5, 10 and 20 mg/kg GRb1 orally via gavage four times before and after surgery. Gastrointestinal motility was assessed by charcoal transport. Systemic inflammation was assessed by serum tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and IL-10 concentrations, whereas intestinal inflammation was assessed by the activity of myeloperoxidase, and concentrations and gene expression of TNF-α, IL-1β, IL-6 and IL-10 in the ileum tissue. The results revealed that GRb1 increased rat gastrointestinal transit with POI. The increased levels of systemic and intestinal inflammatory parameters in POI rats were also reduced by GRb1. In addition, GRb1 reduced systemic and intestinal inflammation and increased the gastrointestinal transit of POI rats in a dose-dependent manner, and with significance at doses of 10 and 20 mg/kg. These results suggest that GRb1 has a potent anti-inflammatory effect on POI and further contributes to the recovery of gastrointestinal motility. GRb1 may be a promising treatment for POI prophylaxis.
Berberine, an isoquinoline alkaloid derived from many medicinal plants, has been extensively used to treat various gastrointestinal diseases. In the present study, we investigated whether berberine ...could ameliorate intestinal mucosal barrier damage induced by peritoneal air exposure for 3 h. Peritoneal air-exposure rats received 100, 150, and 200 mg/kg berberine orally via gavage four times before and after surgery. Blood and terminal ileum samples were collected 24 h after surgery. The serum D-lactate levels were determined using an enzyme-linked immunosorbent assay (ELISA) kit. Intestinal permeability was determined by measuring the intestinal clearance of fluorescein isothiocyanate (FITC)–dextran (FD4). Intestinal inflammation was assessed by measuring myeloperoxidase activity. Intestinal histopathology was also assessed. The results revealed that berberine decreased the serum D-lactate level, intestinal FD4 clearance, and myeloperoxidase activity. Edema and inflammation were reduced by berberine in the intestinal mucosa and submucosa, and the Chiu’s scores, indices of intestinal mucosal injury, also decreased in the berberine-treated group. In addition, berberine exerted these protective effects in a dose-dependent manner, with a significant difference from the control group at doses of 150 and 200 mg/kg. The results suggest that berberine could ameliorate intestinal mucosal barrier damage induced by peritoneal air exposure, which is linked to its anti-inflammatory activity. Berberine may be a promising treatment for intestinal mucosal barrier damage in open abdominal surgery.
Otubain 2 (OTUB2), a deubiquitinating enzyme, overexpression is considered to predict poor outcome in various cancers. However, the function and potential regulatory mechanisms of OTUB2 in gastric ...cancer (GC) progression remains unclear. To determine how OTUB2 participate in GC progression, the gain and loss of-function experiments were conducted in vivo and in vitro . We found that OTUB2 was upregulated in GC samples (n=140) and cells. Moreover, the overall, first progression and post progression survival rates of GC patients with high OTUB2 expression showed a poorer prognosis than that in those patients with low OTUB2 expression. Down-regulation of OTUB2 suppressed sphere formation and reduced expression of stem cell markers in GC cells. Furthermore, OTUB2-silenced GC cells also showed a decreased proliferation, invasion, migration, and in vivo tumorigenic ability. However, OTUB2 overexpression showed the opposite effects. Notably, we demonstrated that OTUB2 increased lysine-specific histone demethylase 1A (KDM1A) expression through deubiquitination. KDM1A, a demethylase known to promote demethylation of downstream genes, was identified to promote the maintenance of cancer stem cell characteristics. Moreover, the alterations caused by OTUB2 overexpression were partly inversed by KDM1A knockdown and in turn KDM1A overexpression reversed the changes induced by OTUB2 shRNA. Taken together, we demonstrate that OTUB2 may serve as a vital driver in GC tumorigenesis by enhancing KDM1A-mediated stem cell-like properties.
Antibiotic-associated diarrhea (AAD) refers to symptoms of diarrhea that cannot be explained by other causes after the use of antibiotics. AAD is thought to be caused by a disruption of intestinal ...ecology due to antibiotics. Fecal Microbiota Transplantation (FMT) is a treatment method that involves transferring microbial communities from the feces of healthy individuals into the patient's gut.
We selected 23 AAD patients who received FMT treatment in our department. Before FMT, we documented patients' bowel movement frequency, abdominal symptoms, routine blood tests, and inflammatory markers, and collected fecal samples for 16S rRNA sequencing to observe changes in the intestinal microbiota. Patients' treatment outcomes were followed up 1 month and 3 months after FMT.
Out of the 23 AAD patients, 19 showed a clinical response to FMT with alleviation of abdominal symptoms. Among them, 82.61% (19/23) experienced relief from diarrhea, 65% (13/20) from abdominal pain, 77.78% (14/18) from abdominal distension, and 57.14% (4/7) from bloody stools within 1 month after FMT. Inflammatory markers IL-8 and CRP significantly decreased after FMT, but there were no noticeable changes in WBC, IL-6, and TNF-α before and after transplantation. After FMT, the abundance of Bacteroides and Faecalibacterium increased in patients' fecal samples, while the abundance of Escherichia-Shigella and Veillonella decreased.
FMT has a certain therapeutic effect on AAD, and can alleviate abdominal symptoms and change the intestinal microbiota of patients.
This study aimed to at explore exploring the biological functions of dysregulated circRNA in Crohn's disease (CD) pathogenesis, with the overarching goal of and providing potential novel therapeutic ...targets. CircRNA microarray and quantitative real time-polymerase chain reaction (qRT-PCR) analyses were performed to investigate and verify the candidate dysregulated circRNA. The Next, clinical, in vivo, and in vitro studies were performed to investigate explore the biological function and mechanisms of the candidate circRNA in CD. The therapeutic effect of poly (lactic-co-glycolic acid)-microspheres (PLGA MSs)-carried oe-circGMCL1 in experimental colitis models of IL-10 knock-out mice was assessed. CircGMCL1 was identified as the candidate circRNA by microarray and qRT-PCR analyses. Results showed that circGMCL1 expression was negatively correlated with CD-associated inflammatory indices, suggesting that it is a CD-associated circRNA. Microarray and bioinformatics analyses identified miR-124-3p and Annexin 7 (ANXA7) as its downstream mechanisms. The in vitro studies revealed that circGMCL1 mediates its effects on autophagy and NLRP3 inflammasome-mediated pyroptosis in epithelial cells through the ceRNA network. Moreover, the in vivo studies identified the therapeutic effect of PLGA MSs-carried oe-circGMCL1 in experimental colitis models. This study suggests that circGMCL1 protects intestinal barrier function against Crohn's colitis through alleviating NLRP3 inflammasome-mediated epithelial pyroptosis by promoting autophagy through regulating ANXA7 via sponging miR-124-3p. Therefore, circGMCL1 can serve as a potential biological therapeutic target for Crohn's colitis.
Many
plants growing in mining areas exhibit high levels of cadmium (Cd) tolerance and accumulation, and thus are ideal organisms for comparative studies on molecular mechanisms of Cd ...hyperaccumulation. However, transcriptomic studies of hyperaccumulative plants in Violaceae are rare.
is an amazing Cd hyperaccumulator in metalliferous areas of China, whereas its relative
is a non-tolerant accumulator that resides at non-metalliferous sites. Here, comparative studies by transcriptome sequencing were performed to investigate the key pathways that are potentially responsible for the differential levels of Cd tolerance between these two
species. A cascade of genes involved in the ubiquitin proteosome system (UPS) pathway were observed to have constitutively higher transcription levels and more activation in response to Cd exposure in
, implying that the enhanced degradation of misfolded proteins may lead to high resistance against Cd in this hyperaccumulator. Many genes related to sucrose metabolism, especially those involved in callose and trehalose biosynthesis, are among the most differentially expressed genes between the two
species, suggesting a crucial role of sucrose metabolism not only in cell wall modification through carbon supply but also in the antioxidant system as signaling molecules or antioxidants. A comparison among transcriptional patterns of some known transporters revealed that several tonoplast transporters are up-regulated in
under Cd stress, suggesting more efficient compartmentalization of Cd in the vacuoles. Taken together, our findings provide valuable insight into Cd hypertolerance in
, and the corresponding molecular mechanisms will be useful for future genetic engineering in phytoremediation.
On the origin of intrinsic randomness of Rayleigh-Benard turbulence Lin, ZhiLiang; Wang, LiPo; Liao, ShiJun
Science China. Physics, Mechanics & Astronomy/Science China. Physics, mechanics & astronomy,
2017, 1-2017, 2017-1-00, 20170101, Letnik:
60, Številka:
1
Journal Article
Recenzirano
Odprti dostop
It is of broad interest to understand how the evolution of non-equilibrium systems can be triggered and the role played by external perturbations. A famous example is the origin of randomness in the ...laminar-turbulence transition, which is raised in the pipe flow experiment by Reynolds as a century old unresolved problem. Although there exist different hypotheses, it is widely believed that the randomness is ＂intrinsic＂, which, however, remains as an open question to be verified. Simulating the modeled Rayleigh- Benard convection system by means of the so-called clean numerical simulation （CNS） with negligible numerical noises that are smaller even than thermal fluctuation, we verify that turbulence can be self-excited from the inherent thermal fluctuation without any external disturbances, i.e. out of nothing. This reveals a relationship between microscopic physical uncertainty and macroscopic randomness, It is found that in physics the system nonlinearity functions as a channel for randomness information, and energy as well, to transport microscopic uncertainty toward large scales. Such scenario can generally be helpful to understand the various relevant phenomena. In methodology, compared with direct numerical simulation （DNS）, CNS opens a new direction to investigate turbulent flows with largely improved accuracy and reliability.
PDF
