Thoracic endovascular aortic repair under venoarterial extracorporeal membrane oxygenation for acute aortic dissection patients: a case report.

Background: Open repair and replacement of the diseased aorta is still the standard treatment for type A aortic dissection (TAAD) in most patients. In endovascular treatment alone, ensuring adequate blood supply to the brain while covering the dissection with a stent is difficult. Case presentation: This study includes a 71-year-old male patient with type A aortic dissection presented at a recent follow-up examination after having undergone thoracic endovascular aortic repair (TEVAR) plus left subclavian artery chimney stent reconstruction for descending aortic dissection 5 years ago. Preoperative computed tomographic angiography, computed tomographic perfusion, and transcranial Doppler showed an intact cerebral arterial ring and good collateral circulation. We successfully performed an endovascular repair of the thoracic aorta with venoarterial extracorporeal membrane oxygenation (V-A ECMO) to protect the craniocerebral blood supply, greatly increase the safety of the operation, and ensure a good prognosis. Conclusion: TEVAR under V-A ECMO protection is beneficial for patients with TAAD because of its minimal trauma, rapid recovery, few complications, and low mortality.

Inhibition of the MLCK/MLC2 pathway protects against intestinal heat stroke-induced injury in rats.

Intestinal barrier dysfunction often exists in the heat stroke (HS) pathological process, which increases intestinal permeability and induces endotoxemia. The upregulation of MLCK is a crucial player affecting intestinal permeability. This study aimed to explore whether inhibiting myosin light chain kinase (MLCK) can improve HS-induced intestinal injury in rats. Twelve-week-old Wistar male rats were divided into three groups: the control group, the HS model group, and the treatment group [HS model + ML-7 (MLCK inhibitor)]. HS impaired the tight junctions in the rat gut and increased permeability. Additionally, increased inflammatory factors in serum, activation of apoptosis, and downregulation of tight junction proteins were observed in intestinal cells. ML-7 significantly inhibited the MLCK/p-MLC2 signaling pathway, increased the expression of tight junction proteins, reduced intestinal permeability, reduced apoptosis and alleviated the intestinal damage caused by HS. ML-7 inhibited HS-induced apoptosis of intestinal epithelial cells by regulating the ERK/p38/HSP70 axis. Furthermore, inhibition of MLCK upregulated HSP70 expression through activation of the ERK pathway and inhibited cell apoptosis by abolishing the p38 MAPK pathway. In conclusion, inhibiting the MLCK/p-MLC2 signaling pathway reduces HS-induced intestinal permeability and protects the intestinal mucosal barrier.

Early versus Delayed Minimally Invasive Intervention for Acute Necrotizing Pancreatitis: An Updated Systematic Review and Meta-Analysis.

BACKGROUND: Nowadays, minimally invasive intervention (MII) has largely replaced delayed open surgery in acute necrotizing pancreatitis (ANP). However, the timing of MII remains unclear. The present study investigated the effect of early versus delayed MII on complications in ANP. METHODS: Studies evaluating the impact of the timing of MII on complications in ANP patients were thoroughly searched on PubMed, Embase, Cochrane Library, and Web of Science from inception to June 2022. The primary outcome of interest was mortality. Secondary outcomes were the incidence of complications. RESULTS: Nine studies reporting 870 patients undergoing MII for ANP were included. No significant difference was found in mortality between the early and delayed intervention groups. In addition, the timing of MII was not associated with the incidence of new-onset respiratory failure, new-onset cardiovascular failure, new-onset renal failure, new-onset multiple organ failure, gastrointestinal fistula or perforation, pancreatic fistula, stent migration, bleeding, venous thrombosis, and new-onset pancreatic endocrine insufficiency. Notably, in the subgroup analysis of biliary and Asian ANP patients, early intervention was associated with a significantly higher risk of new-onset renal failure than delayed intervention. CONCLUSIONS: Early intervention is safe and recommended only for patients with indications for intervention, such as infection.

Label-free detection of histone based on cationic conjugated polymer-mediated fluorescence resonance energy transfer.

A simple and homogeneous histone assay is developed based on histone-induced DNA compressing coupled with cationic conjugated polymer (CCP)-mediated fluorescence resonance energy transfer (FRET). In this strategy, the CCP serves as the FRET donor and SYBR Green I (SG), which can strongly fluoresce not at its free state but after intercalated into the double stranded calf thymus DNA (dsDNA), serves as the acceptor of FRET. In the absence of histone, the dsDNA-SG and CCP combine with each other through electrostatic interaction and the strong FRET from CCP to SG occurs due to the overlapping between the fluorescent emitting spectrum of the CCP and the absorption spectrum of SG. Upon the introduction of histone, the formed compact complex of histone/dsDNA will lead to the compression of dsDNA structure and prevent SG binding to dsDNA and fluorescing, which gives rise to a significant decrease of FRET efficiency between CCP and SG. Thus, the quantitative analysis of histone is realized by monitoring the change of FRET ratio, namely, the intensity ratio of the two emission bands of CCP and SG. Due to the light harvesting and fluorescence amplification properties of CCP, high sensitivity is achieved with a low detection limit of 0.74ng/mL histone. This strategy provides a simple, homogeneous and sensitive strategy for histone analysis in the study of histone-related biological processes.

Similarity of plant functional traits and aggregation pattern in a subtropical forest.

The distribution of species and communities in relation to environmental heterogeneity is a central focus in ecology. Co-occurrence of species with similar functional traits is an indication that communities are determined in part by environmental filters. However, few studies have been designed to test how functional traits are selectively filtered by environmental conditions at local scales. Exploring the relationship between soil characteristics and plant traits is a step toward understanding the filtering hypothesis in determining plant distribution at local scale. Toward this end, we mapped all individual trees (diameter >1 cm) in a one-ha subtropical forest of China in 2007 and 2015. We measured topographic and detailed soil properties within the field site, as well as plant leaf functional traits and demographic rates of the seven most common tree species. A second one-ha study plot was established in 2015, to test and validate the general patterns that were drawn from first plot. We found that variation in species distribution at local scale can be explained by soil heterogeneity and plant functional traits. (From first plot). (1) Species dominant in habitats with high soil ammonium nitrogen and total phosphorus tended to have high specific leaf area (SLA) and relative growth rate (RGR). (2) Species dominant in low-fertility habitats tended to have high leaf dry matter content (LDMC), ratio of chlorophyll a and b (ratioab), and leaf thickness (LT). The hypothesis that functional traits are selected in part by environmental filters and determine plant distribution at local scale was confirmed by the data of the first plot and a second regional site showed similar species distribution patterns.

Copper ion-induced fluorescence band shift of CdTe quantum dots: a highly specific strategy for visual detection of Cu(2+) with a portable UV lamp.

We have developed a new colorimetric strategy that allows visual detection of Cu(2+) under the irradiation of a UV lamp with high specificity based on the phenomenon that copper ions may lead to a fluorescence band shift of CdTe quantum dots (QDs) while other concomitant ions will not.

Stability analysis of ultrasound thick-shell contrast agents.

The stability of thick shell encapsulated bubbles is studied analytically. 3-D small perturbations are introduced to the spherical oscillations of a contrast agent bubble in response to a sinusoidal acoustic field with different amplitudes of excitation. The equations of the perturbation amplitudes are derived using asymptotic expansions and linear stability analysis is then applied to the resulting differential equations. The stability of the encapsulated microbubbles to nonspherical small perturbations is examined by solving an eigenvalue problem. The approach then identifies the fastest growing perturbations which could lead to the breakup of the encapsulated microbubble or contrast agent.

Three-dimensional modeling of the dynamics of therapeutic ultrasound contrast agents.

A 3-D thick-shell contrast agent dynamics model was developed by coupling a finite volume Navier-Stokes solver and a potential boundary element method flow solver to simulate the dynamics of thick-shelled contrast agents subjected to pressure waves. The 3-D model was validated using a spherical thick-shell model validated by experimental observations. We then used this model to study shell break-up during nonspherical deformations resulting from multiple contrast agent interaction or the presence of a nearby solid wall. Our simulations indicate that the thick viscous shell resists the contrast agent from forming a re-entrant jet, as normally observed for an air bubble oscillating near a solid wall. Instead, the shell thickness varies significantly from location to location during the dynamics, and this could lead to shell break-up caused by local shell thinning and stretching.

[Simulation research on the movement and deposition of inhalational particles in the human respiratory tract].

An entire 3-dimensional geometry model from mouth, pharynx, larynx, trachea to triple bifurcation and the mathematics models for the calculation of the fluid flow and inhalational particle movement in the respiratory tract were proposed in this paper. The deposition fraction of inhalational particles in the respiratory tract obtained from the numerical simulation was coincident with the experimental data basically. Particles were traced in the Lagrangian frame, and at the same time, particle deposition fraction and position were recorded based on the models. The movement and deposition of the inhalational particles in the upper respiratory tract were analyzed. The results show that the deposition of inhalational particles in different positions have important correlation with the breathing intensity, particle density and particle diameter; deposition fraction of the inhalational particles in the trachea will increase at high breathing intensity and decrease with particle diameter increased; the deposition fraction of the inhalational particles in the larynx is maximal and can attain 35%, but the influence of the breathing intensity and particle diameter on the deposition fraction is smaller relatively; the deposition fraction of the inhalational particles in the triple bifurcation will decrease observably with particle diameter increased; the deposition fraction of the inhalational particles in the triple bifurcation is higher obviously at medium and small breathing intensity compared with that of high breathing intensity. The simulation results of this paper can provide a foundation for the research of the effect of inhalational particles on the human health and the research of the inhaling remedy in medicine.

A field experimental study of lignin sand stabilizing material (LSSM) extracted from spent-liquor of straw pulping paper mills.

A new technique was introduced for sand stabilization and re-vegetation by use of lignin sand stabilizing material (LSSM). LSSM is a reconstructed organic compound with lignin as the most dominant component from the extracts of black-liquor issued by straw pulp paper mills. Unlike the polyvinyl acetate or foamed asphalt commonly used for dune stabilization, the new material is plant-friendly and can be used with virescence actions simultaneously. The field experimental study was conducted since 2001 in China's Northwest Ningxia Hui Autonomous Region and has been proved that LSSM is effective in stabilizing the fugitive dunes, making the arenaceous plants survive and the bare dune vegetative. The advisable solution concentration is 2% and the optimal field spraying quantity is 2.5 L/m2. The soil nutrients of the stabilized and greened dune, such as organic matter, available phosphorous and total nitrogen are all increased compared with the control treatment, which is certainly helpful to the growth of arenaceous plants. The technique is worthwhile to be popularized because it is provided not only a new method for desertification control but also an outlet for cleaning contaminants issued from the straw paper mills.

Harmonic enhancement of single-bubble sonoluminescence.

It is known from experiment that the light emission from a sonoluminescing bubble can be increased by using more than one driving frequency. In this paper, a systematic method to determine the optimal conditions of pressure amplitude and relative phase for this effect is described. As a specific application, a two-frequency system--26.5 kHz and 53 kHz--is considered. It is found that the maximum temperatures achievable can be appreciably increased with respect to single-frequency drive, still maintaining spherical stability, provided the dissolved inert gas concentration is kept extremely low in order to maintain diffusive stability.