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关键词： CD4(+)Foxp3(+) regulatory T cells   psoriasis   TNF   TNFR1   TNFR2  

摘要： Tumor necrosis factor alpha (TNF) has been implicated in the pathogenesis of psoriasis and anti-TNF therapeutics are used in the treatment of psoriasis in the clinic. However, considerable proportion of patients fail to respond to anti-TNF treatment. Furthermore, anti-TNF therapy induces de novo development of psoriasis in some patients with other type of autoimmune disorders. Therefore, further understanding of the role of TNF-TNFR signaling in pathogenesis of psoriasis remains a critical to devise safer and more effective treatment. In this study, it is shown that in imiquimod-induced mouse psoriasis model, TNF receptor type 1 (TNFR1) deficiency inhibited the development of skin diseases. In sharp contrast, TNF receptor type 2 (TNFR2) deficiency led to more severe psoriasis that was associated with increased Th1 and Th17 responses and reduced number of CD4(+)Foxp3(+) regulatory T cells (Tregs). Importantly, adoptive transfer of WT Tregs was able to attenuate inflammatory responses in imiquimod-treated TNFR2(-/-) mice, suggestive of a role of malfunctioned Tregs in mice deficient in TNFR2. RNA sequencing data revealed that Tregs deficient in TNFR2 exhibited down-regulation of different biological processes linked to proliferative expansion. Taken together, our study clearly indicated that TNFR1 was pathogenic in mouse psoriasis. In contrast, through boosting the proliferative expansion of Tregs, TNFR2 was protective in this model. The data thus suggest that TNFR1-specific antagonist or TNFR2-specific agonist may be useful in the treatment of patients with psoriasis.

关键词： Neurological impaired patients   Preoperative stomach position   Scoliosis   Laparoscopic fundoplication   Delayed gastric emptying   Enteral nutrition  

摘要： Purpose We sometimes experienced prolonged delayed gastric emptying (DGE) in neurologically impaired patients undergoing laparoscopic fundoplication and gastrostomy. We explored the difference in the DGE rate according to the preoperative stomach position. Methods Thirty-two neurological impaired patients who underwent laparoscopic fundoplication and gastrostomy between 2015 and 2019 were classified into two groups based on stomach position: non-elevated stomach position (NESP) and elevated stomach position (ESP). Patients' characteristics, operative result and postoperative gastric emptying were reviewed. Results The 11 ESP patients were significantly older than the 21 NESP patients (p < 0.05). The ESP patients had a significantly heavier body weight (BW) than the NESP patients (p < 0.05). The time taken (days) to reduce gastric drainage (days, below BW x 10 ml) in the NESP (4.3 +/- 3.6) was significantly longer than that of ESP (1.3 +/- 1.6) (p < 0.05). The time taken (days) to achieve full enteral nutrition in the NESP (14.1 +/- 8.9) was significantly longer than that of the ESP patients (8.8 +/- 3.1) (p < 0.05). Conclusion Elevated stomach position (ESP) patients archived full enteral nutrition earlier than NESP patients after laparoscopic fundoplication and gastrostomy. Stomach position correction might, therefore, be involved in the incidence of DGE.

关键词： Mathematical and Computational Engineering  

摘要： This review/research paper deals with the reduction of nonlinear partial differential equations governing the dynamic behavior of structural mechanical members with emphasis put on theoretical aspects of the applied methods and signal processing. Owing to the rapid development of technology, materials science and in particular micro/nano mechanical systems, there is a need not only to revise approaches to mathematical modeling of structural nonlinear vibrations, but also to choose/propose novel (extended) theoretically based methods and hence, motivating development of numerical algorithms, to get the authentic, reliable, validated and accurate solutions to complex mathematical models derived (nonlinear PDEs). The review introduces the reader to traditional approaches with a broad spectrum of the Fourier-type methods, Galerkin-type methods, Kantorovich-Vlasov methods, variational methods, variational iteration methods, as well as the methods of Vaindiner and Agranovskii-Baglai-Smirnov. While some of them are well known and applied by computational and engineering-oriented community, attention is paid to important (from our point of view) but not widely known and used classical approaches. In addition, the considerations are supported by the most popular and frequently employed algorithms and direct numerical schemes based on the finite element method (FEM) and finite difference method (FDM) to validate results obtained. In spite of a general aspect of the review paper, the traditional theoretical methods mentioned so far are quantified and compared with respect to applications to the novel branch of mechanics, i.e. vibrational behavior of nanostructures, which includes results of our own research presented throughout the paper. Namely, considerable effort has been devoted to investigate dynamic features of the Germain-Lagrange nanoplate (including physical nonlinearity and inhomogeneity of materials). Modified Germain-Lagrange equations are obtained using Kirchhoff'

关键词： Differential algebra   Expectation maximization   Halo orbits   Nonlinear filtering   Orbit determination  

摘要： The nonlinear filtering problem plays a fundamental role in multiple space-related applications. This paper offers a new filtering technique that combines Monte Carlo time propagation with a Gaussian mixture model measurement update. Differential algebra (DA) techniques are used as a tool to reduce the computational effort required by particle filters. Moreover, the use of expectation maximization (EM) optimization algorithm leads to a good approximation of the probability density functions. The performance of the new method is assessed in the nonlinear orbit determination problem, for the challenging case of low observations frequency, and in the restricted three-body dynamics.

关键词： congenital LUTO   fetal cystoscopy   fetal megacystis   fetal therapy   lower urinary tract obstruction   posterior urethral valves   urethral atresia   vesicoamniotic shunt  

摘要： Objective To construct reference values for fetal urinary bladder distension in pregnancy and use Z-scores as a diagnostic tool to differentiate posterior urethral valves (PUV) from urethral atresia (UA). Methods This was a prospective cross-sectional study in healthy singleton pregnancies aimed at constructing nomograms of fetal urinary bladder diameter and volume between 15 and 35 weeks' gestation. Z-scores of longitudinal bladder diameter (LBD) were calculated and validated in a cohort of fetuses with megacystis with ascertained postnatal or postmortem diagnosis, collected from a retrospective, multicenter study. Correlations between anatomopathological findings, based on medical examination of the infant or postmortem examination, and fetal megacystis were established. The accuracy of the Z-scores was evaluated by receiver-operating-characteristics (ROC)-curve analysis. Results Nomograms of fetal urinary bladder diameter and volume were produced from three-dimensional ultrasound volumes in 225 pregnant women between 15 and 35 weeks of gestation. A total of 1238 urinary bladder measurements were obtained. Z-scores, derived from the fetal nomograms, were calculated in 106 cases with suspected lower urinary tract obstruction (LUTO), including 76 (72%) cases with PUV, 22 (21%) cases with UA, four (4%) cases with urethral stenosis and four (4%) cases with megacystis-microcolon-intestinal hypoperistalsis syndrome. Fetuses with PUV showed a significantly lower LBD Z-score compared to those with UA (3.95 vs 8.83, P < 0.01). On ROC-curve analysis, we identified 5.2 as the optimal Z-score cut-off to differentiate fetuses with PUV from the rest of the study population (area under the curve, 0.84 (95% CI, 0.748-0.936);P < 0.01;sensitivity, 74%;specificity, 86%). Conclusions Z-scores of LBD can distinguish reliably fetuses with LUTO caused by PUV from those with other subtypes of LUTO, with an optimal cut-off of 5.2. This information should be useful for prenatal counseling

关键词： Permittivity   Torso   Liver   Scattering parameters   Electromagnetics   Permittivity measurement   Antenna measurements   Electromagnetic (EM) imaging   hepatic steatosis   permittivity estimation   scattering parameters  

摘要： Hepatic steatosis is a disorder with high prevalence among obese people. Traditional imaging modalities are more common in hepatic steatosis diagnosis, but they are not suitable for monitoring or treatment evaluation. This study aims at developing a new technique suitable for electromagnetic (EM) tool in the microwave band to differentiate steatotic from nonsteatotic liver. A differential permittivity estimation method for hepatic steatosis detection is proposed. First, the effective permittivity of the right side of the torso is estimated based on the phase difference of EM waves traveling along symmetric paths within the torso. Then, permittivity modeling and statistical frequency selection are performed to model the estimated values and to extract reliable frequency samples. Finally, the percentage of the difference between the permittivity of the left and right sides of the torso is calculated over the selected samples. The effectiveness of the proposed method is validated using simulated signals and phantom measurements. The analyzed results reveal higher contrast between the average permittivity of the left and right sides of the torso for cases with hepatic steatosis (average contrast of 29.2%) compared to those with healthy liver (average contrast of 7.9%). The proposed method can differentiate between steatotic and nonsteatotic liver. It is suitable for clinical applications due to its robustness to unwanted noise and interferences, as well as errors in placement of sensors. The results verify the potential of EM devices, which could overcome shortcomings of traditional imaging techniques by being safe, cost-effective, and portable.

关键词： altered precipitation   arid and humid areas   global climate change   meta-analysis   soil carbon cycles   systematic review  

摘要： Changes in precipitation regimes have significant effects on soil carbon (C) cycles;however, these effects may vary in arid versus humid areas. Additionally, the corresponding details of soil C cycles in response to altered precipitation regimes have not been well documented. Here, a meta-analysis was performed using 845 pairwise observations (control vs. increased or decreased precipitation) from 214 published articles to quantify the responses of the input process of exogenous C, the contents of various forms of C in soil, and the soil-atmosphere C fluxes relative to increased or decreased precipitation. The results showed that the effects of altered precipitation regimes did not differ between rainfall and snowfall. Increased precipitation significantly enhanced the soil C inputs, pools and outputs by 18.17%, 18.50%, and 21.04%, respectively, while decreased precipitation led to a significant decline in these soil C parameters by 10.18%, 9.96%, and 17.98%, respectively. The effects of increased precipitation on soil C cycles were more significant in arid areas (where mean annual precipitation, MAP <500 mm), but the effects of decreased precipitation were more significant in humid areas (where MAP >= 500 mm), indicating that the original MAP partially determined the responses of the soil C cycles to altered precipitation regimes. This study implies that for the same of precipitation variation, soil C cycles respond at different magnitudes: not only should the direction (decrease vs. increase) be counted but also the region (arid vs. humid) should be considered. These results deepened our understanding on regional differentiation in soil C cycles under climate change scenarios.

关键词： Mixed delays   Exponential ultimate boundedness   Neutral stochastic differential systems  

摘要： This article aims to investigate the boundedness of neutral stochastic differential systems with mixed delays. By virtue of Ito formula and some important inequali-ties, several pth moment exponential ultimate boundedness conditions are obtained for the considered systems. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Uncertainty theory   Fractional differential equation   Extreme value   Time integral   Option pricing  

摘要： Uncertain fractional differential equations have been playing an important role in modelling complex dynamic systems. Early researchers have presented the extreme value theorems and time integral theorem on uncertain fractional differential equation. As applications of these theorems, this paper investigates the pricing problems of American option and Asian option under uncertain financial markets based on uncertain fractional differential equations. Then the analytical solutions and numerical solutions of these option prices are derived, respectively. Finally, some numerical experiments are performed to verify the effectiveness of our results.

关键词： Intestinal transplant   Intestinal allograft dysfunction   Acute cellular rejection (ACR)   Infectious enteritis   Surveillance endoscopy   Macrophage derived chemokine (MDC)   Immune monitoring  

摘要： Background/objectives: Rejection and infectious enteritis in intestinal transplant (ITx) patients present with virtually identical symptoms. Currently, the gold standard for differentiating between these two conditions is endoscopy, which is invasive and costly. Our primary aim was to identify differences in peripheral blood cytokines during episodes of acute cellular rejection (ACR) and infectious enteritis in patients with intestinal transplants. Methods: This was a prospective, cross-sectional study involving ITx patients transplanted between 2000 and 2016. We studied 63 blood samples collected from 29 ITx patients during periods of normal (n = 24) and abnormal (n = 17) allograft function. PBMCs from whole blood samples were cultured under unstimulated or stimulated conditions with phytohemagglutinin (PHA). The supernatant from these cultures were collected to measure cytokine and chemokine levels using a 38-plex luminex panel. Results: Our study found that cytokines and chemokines are differentially expressed in normal, ACR, and infectious enteritis samples under unstimulated conditions based on heatmap analysis. Although each cohort displayed distinctive signatures, only MDC (p = 0.037) was found to be significantly different between ACR and infectious enteritis. Upon stimulation of PBMCs, patients with ACR demonstrated increased immune reactivity compared to infectious enteritis;though this did not reach statistical significance. Conclusions: To our knowledge, this is the first comprehensive study comparing cytokine expression during acute rejection and infectious enteritis in intestinal transplant recipients. Our results suggest that cytokines have the potential to be used as clinical markers for risk stratification and/or diagnosis of ACR and infectious enteritis.